Introduction: Resistance to antituberculosis drugs and adverse drug reactions remain the leading causes of tuberculosis therapeutic failure globally. Despite the increasing acceptance of medicinal plant use in combina...Introduction: Resistance to antituberculosis drugs and adverse drug reactions remain the leading causes of tuberculosis therapeutic failure globally. Despite the increasing acceptance of medicinal plant use in combination with conventional antituberculosis drugs in treatment of tuberculosis (TB) in Uganda, there is paucity of knowledge on their combination effect. Aim: This research aimed to determine combination activity of standard antituberculosis drugs with extracts of Zanthoxylum leprieurii Guill. & Perr. and Rubia cordifolia L., the two common antituberculosis medicinal plants in Uganda, against pansensitive (H37Rv) and multi-drug resistant (MDR) Mycobacterium tuberculosis strains. Materials and Methods: Two reference MTB strains (H37Rv and MDR strain) were inoculated on Middlebrook 7H11 medium containing a combination of standard antituberculosis drugs and methanol extracts of Z. leprieurii and R. cordifolia at varying concentrations. The number of colonies on the plates was observed and counted weekly for up to 8 weeks. In vitro combination activity was determined using proportion method. Mean percentage inhibition was calculated for the reduction of number of colonies on drug-extract combination medium in relation to drug-extract-free control medium. Results: Drug-extract combinations showed good combination activity against Mycobacterium tuberculosis strains when compared with individual standard anti-TB drugs. This was more exhibited against MDR strain. There was however a reduction in percentage inhibition when extracts were combined with ethambutol and streptomycin against H37Rv strain. Conclusions: Zanthoxylum leprieurii and Rubia cordifolia in combination with standard anti-TB drugs exhibited increased in vitro activity against Mycobacterium tuberculosis, especially MDR-TB strain. This justifies the local use of these plants in traditional treatment of tuberculosis especially in resistant cases in Uganda.展开更多
This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoli...This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and ferric thiocyanate lipid peroxidation antioxidant assays were performed. High performance liquid chromatography was used to identify phenolic acids. There was no solvent effect on TPC nor on scavenging activities, and inhibition of lipid peroxidation (p > 0.05) among solvent extracts. On the other hand, 1:1:3 water: acetone: methanol extract (10.22 mg GAE/g sample) had significantly higher reducing potential than 50% ethanol extract (EE) (9.259 mg GAE/g sample) (p < 0.05);but EE was not significantly different from 80% methanol extract (9.781 mg GAE/g sample) (p > 0.05). Phenolic fraction designated as fraction 4 had the highest antioxidant activity (p < 0.05) with 69.49% ABTS scavenging activity and FRAP reducing potential, 22.26 mg of GAE/g sample. DPPH scavenging activities of fractions 4 (55.59%) and 5 (55.64%) were significantly higher than the other fractions (p A. rigidula extracts contain gallic, caffeic, vanillic, p-coumaric, salicylic acids and vanillin.展开更多
It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of s...It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica var.gobica,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,China.We recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July 2023.Soil samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme activities.The results showed that the plant coverage and aboveground biomass of S.laricifolia community were significantly higher than those of C.tragacanthoides,S.breviflora,and S.tianschanica var.gobica communities(P<0.05).Soil enzyme activities varied among different plant communities.In the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in E.rhytidosperma and S.tianschanica var.gobica communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the subsoil.Specifically,the content of POC in the topsoil was 18.17%–42.73%higher than that in the subsoil.The structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and MAOC.The soil pH inhibited the formation of POC and promoted the formation of MAOC.Conversely,SWC stimulated POC production and hindered MAOC formation.Our study aimed to gain insight into the effects of desert plant communities on soil enzyme activities and SOC fractions,as well as the drivers of SOC fractions in the proluvial fan in the eastern foothills of the Helan Mountain and other desert ecosystems.展开更多
With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej...With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance.展开更多
Endophytes,as crucial components of plant microbial communities,significantly contribute to enhancing the absorption of nutrients such as nitrogen and phosphorus by their hosts,promote plant growth,and degrade pathoge...Endophytes,as crucial components of plant microbial communities,significantly contribute to enhancing the absorption of nutrients such as nitrogen and phosphorus by their hosts,promote plant growth,and degrade pathogenic fungal mycelia.In this study,an experiment was conducted in August 2022 to explore the growth-promoting potential of endophytic bacterial strains isolated from two medical plant species,Thymus altaicus and Salvia deserta,using a series of screening media.Plant samples of Thymus altaicus and Salvia deserta were collected from Zhaosu County and Habahe County in Xinjiang Uygur Autonomous Region,China,in July 2021.Additionally,the inhibitory effects of endophytic bacterial strains on the four pathogenic fungi(Fusarium oxysporum,Fulvia fulva,Alternaria solani,and Valsa mali)were determined through the plate confrontation method.A total of 80 endophytic bacterial strains were isolated from Thymus altaicus,while a total of 60 endophytic bacterial strains were isolated from Salvia deserta.The endophytic bacterial strains from both Thymus altaicus and Salvia deserta exhibited plant growth-promoting properties.Specifically,the strains of Bacillus sp.TR002,Bacillus sp.TR005,Microbacterium sp.TSB5,and Rhodococcus sp.TR013 demonstrated strong cellulase-producing activity,siderophore-producing activity,phosphate solubilization activity,and nitrogen-fixing activity,respectively.Out of 140 endophytic bacterial strains isolated from Thymus altaicus and Salvia deserta,104 strains displayed anti-fungal activity against Fulvia fulva,Alternaria solani,Fusarium oxysporum,and Valsa mali.Furthermore,the strains of Bacillus sp.TR005,Bacillus sp.TS003,and Bacillus sp.TSB7 exhibited robust inhibition rates against all the four pathogenic fungi.In conclusion,the endophytic bacterial strains from Thymus altaicus and Salvia deserta possess both plant growth-promoting and anti-fungal properties,making them promising candidates for future development as growth-promoting agents and biocontrol tools for plant diseases.展开更多
Tuberculosis (TB) remains a public health challenge and one of the leading causes of death worldwide. TB is preventable and curable. However, treatment of tuberculosis has continued to be difficult as a result of rapi...Tuberculosis (TB) remains a public health challenge and one of the leading causes of death worldwide. TB is preventable and curable. However, treatment of tuberculosis has continued to be difficult as a result of rapid increase of multidrug and extensively drug resistant strains of Mycobacterium tuberculosis. Medicinal plants have for centuries been traditionally used in treatment of tuberculosis and similar ailments. They possess antimicrobial properties which render them a new hope as a source of novel bioactive leads in the development of antimycobacterial agents. In this study, 2 plant species commonly used traditionally in Uganda for treatment of tuberculosis, Zanthoxylum leprieurii and Rubia cordifolia were screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis strains;pan sensitive MTB H37Rv, Rifampicin resistant TMC 331 strain and two wild strains (one rifampicin resistant and another one rifampicin susceptible). Antimycobacterial activity of aqueous, ethanolic and methanolic plant extracts was determined using Resazurin Microtiter Assay (REMA). Both plant extracts exhibited significant in vitro antimycobacterial activity against all strains of Mycobacterium tuberculosis. Minimum inhibitory concentrations (MIC) of methanolic crude extracts of both plants ranged from 23.4 μg/mL to 187.5 μg/mL. Comparatively, methanol extracts of both plants possessed superior antimycobacterial activity against all Mycobacterium tuberculosis strains. Our findings indicated that both plants exhibited activity against susceptible and resistant strains of Mycobacterium tuberculosis. While antimycobacterial activity of Z. leprieurii confirms results from previous studies, activity of the extracts of R. cordifolia is reported for the first time in East Africa. Further studies aimed at determining the effects of combination of these plant extracts and standard anti-TB drugs should be carried out.展开更多
To investigate the effects of different vegetable growing regions and planting modes on soil quality,soils in high,medium and low altitude areas of Guizhou were respectively sampled under different vegetable efficient...To investigate the effects of different vegetable growing regions and planting modes on soil quality,soils in high,medium and low altitude areas of Guizhou were respectively sampled under different vegetable efficient planting modes,and the variations of soil microbial flora and enzyme activities were analyzed. The soil microbial count and total bacteria of the vegetable efficient cultivation mode were significantly higher than that of the control (traditional planting mode) in each planting area,and the microbial diversity index was also improved to varying de- grees.The soil phosphatase,catalase and urease activities of the vegetable efficient planting mode were higher than that of the control.The soil catalase and urease activities were higher than that of the control by 1.37-1.44 and 1.51-2.80 times. Application of vegetable efficient planting mode in different regions will help to im- prove the soil quality in a given period.展开更多
Objective:To assess the antibacterial activity of eight Iranian plant extracts against Staphylococcus aureus(S.aureus) strains which were isolated from infected patients.Methods: The studied strains were isolated from...Objective:To assess the antibacterial activity of eight Iranian plant extracts against Staphylococcus aureus(S.aureus) strains which were isolated from infected patients.Methods: The studied strains were isolated from urine,stool,blood and wound of infected patients and identified by biochemical tests.In further,the antibacterial activity of 8 ethanolic local plant extracts including Querqus brantii(Q.brantii),Ziziphus spina-christi(Z.spina-christi),Peganum harmala(P.harmala),Oliveira decumbens(O.decumbens),Galium tricornutum(G.tricornutum), Vitex pseudo negundo(Vi.pseudo negundo),Salvia officinalis(S.officinalis),Vaccaria pyramidata (V.pyramidata) were then evaluated using agar disc diffusion method.Results:A total of 9 isolates were isolated and identified as S.aureus.Antibacterial profile of the strains showed that the strains were resistant to methicillin and cefixime.The highest antibacterial activity against the studied strains were belong to Q.brantii,P.harmala,Z.spina-christi and O.decumbens vent extracts with 11-40 mm,15-28 mm,8-26 mm and 10-20 mm of diameters,respectively. Intermediate antibacterial activity was exhibited by G.tricornutum and Vi.pseudo negundo against some of the studied strains with 7-20 mm and 7-13 mm of diameters,respectively. Noteworthy,out of 9 studied strains;6 and 2 of them were resistant to the G.tricornutum and Vi. pseudo negundo extracts,respectively.The S.officinalis and Va.pyramidata,however,showed no antibacterial activity against the studied strains.Conclusions:The Q.brantii,P.harmala,Z. spina-christi and O.decumbens extracts were shown to possess strong antibacterial activity against methicillin and cefixime resistant S.aureus strains and can be considered as the promising natural antibiotics for treating the studied strains.展开更多
Objective:To evaluate the larvicidal and repellent activities of ethyl acetate and methanol extracts of Acacia concinna(A.concinna),Cassia siamea(C.siamea).Conundrum sativum(C. sativum),Cuminum cyminum(C.cyminu...Objective:To evaluate the larvicidal and repellent activities of ethyl acetate and methanol extracts of Acacia concinna(A.concinna),Cassia siamea(C.siamea).Conundrum sativum(C. sativum),Cuminum cyminum(C.cyminum),Lantana camma(L.camara),Nelumbo nucifera (N.nucifera) Phyllanlhus amarus(P.amarus).Piper nigrum(P.nigrum) and Trachyspermum ammi(T.ammi) against Anopheles stephensi(An.stephensi) and Culex quinquefasciatus(Cx. quinquefasciatus).Methods:The larvicidal activity of medicinal plant extracts were tested against earl) fourth-instar larvae of malaria and filariasis vectors.The mortality was observed 24 h and 48 h after treatment,data were subjected to probit analysis to determine the lethal concentrations(LC<sub>50</sub> and LC<sub>90</sub>) to kill 50 and 90 per cent of the treated larvae of the tested species. The repellent efficacy was determined against two mosquito species at five concentrations(31.25. 62.50.125.00.250.00,and 500.00 ppm) under the laboratory conditions.Results:All plant extracts showed moderate effects after 24 h and 48 h of exposure;however,the highest activity was observed after 24 h in the leaf methanol extract ol N.nucifera.seed ethyl acetate and methanol extract of P.nigrum against the larvae of An.Stephensi(LC<sub>50</sub> = 34.76.24.54 and 30.20 ppm) and against Cx.quinquefasciatus(LC<sub>50</sub>= 37.49.43.94 and 57.39 ppm),respectively.The toxic effect of leaf methanol extract of C.siamea,seed methanol extract of C.cyminum,leaf ethyl acetate extract of N.nucifera.leaf ethyl acetate and methanol extract of P.amarus and seed methanol extract of T.ammi were showed 100%mortality against An.stephensi and Cx.quinquefasciatus alter 48 h exposer.The maximum repellent activity was observed at 500 ppm in methanol extracts of N. nucifera.ethyl acetate and methanol extract of P.nigrum and methanol extract of T.ammi and the mean complete protection time ranged from 30 to 150 min with the different extracts tested. Conclusions:These results suggest that the leaf and seed extracts of C.siamea.N.nucifera.P. amarus.P.nigrum and T.ammi have the potential to be used as an ideal ecofriendly approach for the control of the An.stephensi and Cx.quinquefasciatus.展开更多
The beet armyworm,Spodoptera exigua (Lepidoptera:Noctuidae),is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citru...The beet armyworm,Spodoptera exigua (Lepidoptera:Noctuidae),is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citrus crops.In this study,performance and subsequent enzyme activity of beet armyworm reared on host plants from five families were investigated.Significant differences were found in development,fecundity and enzyme activity on different host plants.Survival rate was the highest (42.8%) on asparagus lettuce (Lactuca sativar var.asparagina) and the lowest (17.0%) on sweet pepper (Capsicum annuum).Larval duration was the shortest on asparagus lettuce (12.0 d),and was 43.4% longer on sweet peppers (21.2 d).The activity of acetylcholine esterase (AChE) and carboxylesterase (CarE) in 3rd instar larvae,and soluble carbohydrate and crude protein contents in different host plants were determined.AChE activity was the highest in the larvae feeding on Chinese cabbage (Brassica rapa),but declined by nearly 60% on maize (Zea mays) seedlings.The ratio of soluble carbohydrate content to crude protein content in host plants was found to have a positive effect on oviposition and a negative correlation with larval duration and life time (from larval to adult stages) of the insect.展开更多
To improve the productivity of poplar planta- tions, a field experiment of split-plot design with four tree spacings and three poplar clones was established, and four soil enzyme activities and microbial biomass were ...To improve the productivity of poplar planta- tions, a field experiment of split-plot design with four tree spacings and three poplar clones was established, and four soil enzyme activities and microbial biomass were monitored in the trial. Soil enzyme activities, in most cases, were significantly higher in topsoil (0-10 cm) than in lower horizons (10-20 cm). Soil cellulase, catalase and protease activities during the growing season were higher than during the non-growing season, while invertase activity followed the opposite trend. Soil invertase, cellulase and catalase activities varied by poplar clone but soil protease activity did not. Cellulase and protease activities in the plantation at 5 × 5 m spacing were significantly higher than in the other spacings. The highest catalase activity was recorded at 6 × 6 m spacing. At the same planting density, invertase activity was greater in square spacings than in rectangular spacings. Soil microbial biomass was also significantly affected by seedling spacing and poplar clone. The mean soil MBC was significantly lower in topsoil than in the lower horizon, while MBN showed the opposite pattern. Significantly positive correlations were observed among soil cellulase, protease and catalase activities (p 〈0.01), whereas soil invertase activity was negatively and significantly correlated with cellulase, protease and catalase activities (p 〈 0.01). Soil microbial biomass and enzyme activities were not correlated except for a significantly negative correlation between soil MBC and catalase activities. Variations in soil enzyme activity and microbial biomass in different poplar plantations suggest that genotype and planting spacing should be considered when modeling soil nutrient dynamics and managing for long-term site productivity.展开更多
As one of the most sensitive regions to global climate change, alpine tundra in many places around the world has been undergoing dramatic changes in vegetation communities over the past few decades.Herbaceous plant sp...As one of the most sensitive regions to global climate change, alpine tundra in many places around the world has been undergoing dramatic changes in vegetation communities over the past few decades.Herbaceous plant species in the Changbai Mountains area have significantly expanded into tundra shrub communities over the past 30 yr.Soil microbial communities, enzyme activities, and soil nutrients are intertwined with this expansion process.In order to understand the responses of the soil microbial communities to such an expansion, we analyzed soil microbial community structures and enzyme activities in shrub tundra as well as areas with three different levels of herbaceous plant expansion.Our investigation was based on phospholipid fatty acid(PLFA) analysis and 96-well microtiter plates.The results showed that herbs have expanded greatly in the tundra, and they have become the dominant species in herbaceous plant expansion areas.There were differences for community composition and appearance among the shrub tundra and the mild expansion, moderate expansion, and severe expansion areas.Except for soil organic matter, soil nutrients were increased in herbaceous plant expansion areas, and the total nitrogen(TN), total phosphorus(TP), available nitrogen(AN), and available phosphorus(AP) were greatest in moderate expansion areas(MOE), while soil organic matter levels were highest in the non-expanded areas(CK).The total soil PLFAs in the three levels of herbaceous plant expansion areas were significantly higher than those in the non-expanded areas, and total soil PLFAs were highest in the moderately expanded area and lowest in the severely expanded area(SEE).Bacteria increased significantly more than fungi and actinomycetes with herbaceous plant expansion.Soil hydrolase activities(β-1,4-glucosidase(βG) activity, β-1, 4-N-acetylglucosaminidase(NAG) activity, and acid phosphatase(aP) activity) were highest in MOE and lowest in the CK treatment.Soil oxidase activities(polyphenol oxidase(PPO) activities and peroxidase(PER) activities) were also highest in MOE, but they were lowest in the SEE treatment.The variations in total soil PLFAs with herbaceous plant expansion were mostly correlated with soil organic matter and available phosphorus concentrations, while soil enzyme activities were mostly correlated with the total soil nitrogen concentration.Our results suggest that herbaceous plant expansion increase the total soil PLFAs and soil enzyme activities and improved soil nutrients.However, soil microorganisms, enzyme activity, and nutrients responded differently to levels of herbaceous plant expansion.The soil conditions in mild and moderate expansion areas are more favorable than those in severe expansion areas.展开更多
Objective:To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis,wound and gastrointestinal complications.Methods:Hydroalcoholic exctracts of medicinal pla...Objective:To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis,wound and gastrointestinal complications.Methods:Hydroalcoholic exctracts of medicinal plants namely,Achyranthes aspera(A.aspera) L.(Family Asparagaceae),Ficus caria(F.caria)(Family Moraceae).Malvi parviflora(M.parviflora)(Family Malvaceae),Vernonia species(V.species) docal name Alakit.Family Asteraceae),Solatium hastifolium(S.hastifolium)(Family Solanaceae),Calpurinia aurea(C.aurea)(Ait) Benth(Family Fabaceae),Nicotiana tabacum(N.tabacum) L.(Family Solanaceae),Ziziphus spina-christi(Z.spina-christi)(Family Rhamnaceae).Croton macroslachys(C.macrostachys)(Family Fuphorhiaceae).were screened against clinical bacterial isolates of veterinary importance from October 2007 to April2009.The antibacterial activity was tested using disc diffusion at two concentrations(200 mg/mL and 100 mg/mL) and broth dilution methods using 70%methanol macerated leal extracts.Results:With the exception ol S.hastifolium all plant extracts exhibited antibacterial activity.Among the medicinal plants tested C.aurea.C.macrostachyus,A.aspera,N.tabacum and vcrnonia species(Alakit) showed the most promising antimicrobial properties.Conclusions:It can be concluded that many of the tested plants have antibacterial activity and supports the traditional usage of the plants for mastitis,wound and gastrointestinal complications treatment.Further studies into their toxicity and phytochemistry is advocated.展开更多
More than 50% of the world population is infected with Helicobacter pylori (H. pylori). The bacterium highly links to peptic ulcer diseases and duodenal ulcer, which was classified as a group I ...More than 50% of the world population is infected with Helicobacter pylori (H. pylori). The bacterium highly links to peptic ulcer diseases and duodenal ulcer, which was classified as a group I carcinogen in 1994 by the WHO. The pathogenesis of H. pylori is contributed by its virulence factors including urease, flagella, vacuolating cytotoxin A (VacA), cytotoxin-associated gene antigen (Cag A), and others. Of those virulence factors, VacA and CagA play the key roles. Infection with H. pylori vacA-positive strains can lead to vacuolation and apoptosis, whereas infection with cagA-positive strains might result in severe gastric inflammation and gastric cancer. Numerous medicinal plants have been reported for their anti-H. pylori activity, and the relevant active compounds including polyphenols, flavonoids, quinones, coumarins, terpenoids, and alkaloids have been studied. The anti-H. pylori action mechanisms, including inhibition of enzymatic (urease, DNA gyrase, dihydrofolate reductase, N-acetyltransferase, and myeloperoxidase) and adhesive activities, high redox potential, and hydrophilic/hydrophobic natures of compounds, have also been discussed in detail. H. pylori-induced gastric inflammation may progress to superficial gastritis, atrophic gastritis, and finally gastric cancer. Many natural products have anti-H. pylori-induced inflammation activity and the relevant mechanisms include suppression of nuclear factor-κB and mitogen-activated protein kinase pathway activation and inhibition of oxidative stress. Anti-H. pylori induced gastric inflammatory effects of plant products, including quercetin, apigenin, carotenoids-rich algae, tea product, garlic extract, apple peel polyphenol, and finger-root extract, have been documented. In conclusion, many medicinal plant products possess anti-H. pylori activity as well as an anti-H. pylori-induced gastric inflammatory effect. Those plant products have showed great potential as pharmaceutical candidates for H. pylori eradication and H. pylori induced related gastric disease prevention.展开更多
Objective:To evaluate the mosquito larvicidal activity of plant extracts.Methods:The hexane,chloroform,ethyl acetate,acetone,and methanol leaf,flower and seed extracts of Abrus precatorius(A.precatorius),Croton bonp...Objective:To evaluate the mosquito larvicidal activity of plant extracts.Methods:The hexane,chloroform,ethyl acetate,acetone,and methanol leaf,flower and seed extracts of Abrus precatorius(A.precatorius),Croton bonplandianum(C.bonplandianum),Cynodon dactylon (C.dactylon),Musa paradisiaca(M.paradisiaca) and Syzygium aromaticum(S.aromaticum) were tested against fourth instar larvae of Anopheles vagus(An.vagus),Armigeres subalbatus (Ar.subalbatus) and Culex vishnui(Cx.vishnui).Results:The highest larval mortality was found in seed ethyl acetate extracts of A.precatorius and leaf extracts of C.bonplandianum, flower chloroform and methanol extracts of M.paradisiaca,and flower bud hexane extract of S. aromaticum against An.vagus with LC<sub>50</sub> values of 19.31,39.96,35.18,79.90 and 85.90μg/mL;leaf ethyl acetate and methanol extracts of C.dactylon,flower methanol extract of M.paradisiaca, flower bud methanol extract of S.aromaticum against Ar.subalbatus with LC<sub>50</sub> values of 21.67, 32.62,48.90 and 78.28μg/mL,and seed methanol of A.precatorius,flower methanol extract of M.paradisiaca,flower bud hexane extract of S.aromaticum against Cx.vishnui with LC<sub>50</sub> values of 136.84,103.36 and 149.56μg/mL,respectively.Conclusions:These results suggest that the effective plant crude extracts have the potential to be used as an ideal ecofriendly approach for the control of disease vectors.This study provides the first report on the larvicidal activity of crude solvent extracts of different mosquitoes.展开更多
Flavonoids are natural organic compounds that are widely found in nature, their structural types are complex, and they mainly include flavonoids, flavonols, dihydroflavonols, isoflavones, dihydroisoflavones, chalcones...Flavonoids are natural organic compounds that are widely found in nature, their structural types are complex, and they mainly include flavonoids, flavonols, dihydroflavonols, isoflavones, dihydroisoflavones, chalcones, orange ketones, flavanoids, anthocyanidins, and biflavonoids. This review covers the plant distribution and pharmacological activities of flavonoids. Flavonoids are mainly distributed in angiosperms and gymnosperms, and they are abundant in plants such as Rutaceae, Labiatae, Zingiberaceae, Scrophulariaceae, and Leguminosae. Because of their wide distribution and variety, researchers have found that flavonoids have diverse biological activities, mainly focusing on anti-inflammatory, antibacterial and antitumor activities. Mechanistically, the anti-inflammatory effects are mainly related to the NF-κB and MAPK (mitogen-activated protein kinase) signaling pathway and then the inhibition of the production of inflammatory cytokines and mediators. The antibacterial activity is mainly manifested as inhibitory effects on many strains, including Escherichia coli, Cryptococcus neoformans, and Pseudomonas aeruginosa, via destroying the stability of the microbial membrane, inhibiting the invasion of virulent bacteria into host cells, promoting the apoptosis of bacteria, inhibiting bacterial fatty acid synthesis, etc. The antitumor activity of flavonoids is related to their inhibition of cell proliferation and induction of apoptosis via the mitochondria-mediated, endoplasmic reticulum-mediated, and death factor and its receptor-mediated signal transduction pathways. Understanding the plant distribution and pharmacological activity of flavonoids not only reveals the importance of identifying such valuable flavonoids in another genus or family but also provides a basis for fully exploiting the therapeutic potential of flavonoids.展开更多
Acorus tatarinowii Schott is a traditional Chinese medicine plant and has multiple bioactivities in medicine and pesticide field. In this study, the antifungal compound 1,2-dimethoxy-4(2-propenyl) benzene was isolat...Acorus tatarinowii Schott is a traditional Chinese medicine plant and has multiple bioactivities in medicine and pesticide field. In this study, the antifungal compound 1,2-dimethoxy-4(2-propenyl) benzene was isolated from A. tatarinowii Schott by activity-directed isolation method, and the inhibitory activity of the extract and 1,2-dimethoxy-4(2-propenyl) benzene against seven plant pathogenic fungi was evaluated. The results showed that the extract and 1,2-dimethoxy-4(2- propenyl) benzene had high inhibitory activity against hyphal growth of Thielaviopsis paradoxa (de Seynes) V. Hohnel, Pestalotia mangiferae P. Henn., Fusarium oxysporum f. sp. niveum (E. F. Smith) Syn. et Hans., Alternaria alternate Tanaka, Colletotrichum musae (Berk et Curt) V. Arx, Sphaceloma fawcettii Jenk., and Mycosphaerella sentina (Fr.) Schroter. The EC50 values of extract were 1.6162, 1.6811, 1.1253, 3.5771, 1.7024, 2.2284, and 2.2221 g L^-1, respectively, and the EC50 values of 1,2-dimethoxy-4(2-propenyl) benzene were 0.1021, 0.0997, 0.0805, 0.1742, 0.1503, 0.1853, and 0.1924 g L^-1, respectively. 1,2-Dimethoxy-4(2-propenyl) benzene also inhibited spores germination of T. paradoxa (de Seynes) V. Hohnel and F. oxysporum f. sp. niveum (E. F. Smith) Syn. et Hans., with the inhibitory rates of 98.81 and 100% at a concentration of 0.4 g L^-1 after 8 h, respectively. 1,2-Dimethoxy-4(2-propenyl) benzene is a potential botanical antifungal agent for controling of plant fungal diseases.展开更多
Plant material screening was performed to study anti-Helicobacter pylori activity in vitro using an agar diffusion method on Columbia blood agar. 33 substances, juices and plant extracts and 35 of their combinations w...Plant material screening was performed to study anti-Helicobacter pylori activity in vitro using an agar diffusion method on Columbia blood agar. 33 substances, juices and plant extracts and 35 of their combinations were tested. Quince (Cydonia oblonga) juice demonstrated the strongest anti-H. pylori activity followed by cranberry juice. Con-centrated apple juice, plum, red currant, black chokeberry, raspberry and bilberry juice also showed significant activity. Green tea and apple pomace extract as well as sweet flag rhizome, ginger and wild bergamot extract, cherry syrup, red beet juice and whey did not exhibit anti-Helicobacter activity. Quince juice in combination with bilberry, black chokeberry, red currant juice, green tea, sweet flag rhizome or apple pomace extract as well as cranberry juice in combination with sweet flag rhizome extract demonstrated a synergistic effect on inhibition of H. pylori. The obtained results offer new perspectives for development of functional anti-Helicobacter food product(s) for dietary management of H. pylori infection. The essential components of these products could be the most active juices and extracts like quince and cranberry juice supplemented with a corresponding synergist. Further studies are required to investigate the mechanism of antibacterial action of plant products and their efficacy in vivo.展开更多
Leishmaniasis is considered as an emerging, uncontrolled disease and is endemic in 98 countries. Annually, about 2 million cases of cutaneous and 500000 cases of visceraltype leishmaniasis are recorded and 60000 perso...Leishmaniasis is considered as an emerging, uncontrolled disease and is endemic in 98 countries. Annually, about 2 million cases of cutaneous and 500000 cases of visceraltype leishmaniasis are recorded and 60000 persons died from the disease. In Mexico,cutaneous leishmaniasis is known as chiclero's ulcer and is reported in 22 states, it is considered as a health problem. For its treatment, pentavalent antimonial drugs are administered. These drugs cause severe side effects, are costly. Drug-resistant cases have been reported and have been developing for over 70 years. One alternative to the drugs that are currently available is to find active molecules in medicinal plants. Dihydrocorynantheine, corynantheine and corynantheidine are active against Leishmania major,while harmane, pleiocarpin, buchtienin, luteolin and quercetin are active against Leishmania donovani. In Mexico, about 20 medicinal plants have been evaluated against Leishmania mexicana, among which the most active are Tridax procumbens, Lonchocarpus xuul and Pentalinon andrieuxii. From these plants, active compounds with IC_(50)≤30 mg/mL or m M have been isolated, such as 3(S)-16,17-didehydrofalcarinol or Oxylipin, cholestra-4,20,24-trien-3-one or pentalinosterol, 24-methylcholest-4-24(28)-dien-3-one, cholest-4-en-3-one, 6,7-dihydroneridie-none, neridienone, cholest-5,20,24-trien-3β-ol, and isocordoin. Today, only pentalinonsterol has been synthesized and assayed in the visceral leishmaniasis experimental model using BALB/c mice infected with Leishmania donovani. Liposome formulation of this compound administered by intravenous route at 2.5 mg/kg showed a significant reduction of parasite load in mouse liver and spleen.展开更多
Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was ...Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was the highest among the plants. Ruta chalepensis had high levels of fat and carbohydrates (4.2% and 51.7%, respectively), but had the lowest level of ash (8.7%). Mineral concentrations varied and found to have appreciable amounts of Ca, Na, K, Cu, Fe, Mg, Mn, Zn and P. Total phenolic ranged from 163.1 (Tetragonolobus palaestinus) to 1328.8 mg GAE/100g (Ruta chalepensis). Anthocyanins ranged between 18.1 (Gundelia tournefortii) and 100.1 mg/100g (Rumex acetosella). These plants differed in free radical scavenging activity. It was concluded that these plants could be considered as natural sources for antioxidants and valuable natural resources as a new addition to the diet of inhabitants.展开更多
文摘Introduction: Resistance to antituberculosis drugs and adverse drug reactions remain the leading causes of tuberculosis therapeutic failure globally. Despite the increasing acceptance of medicinal plant use in combination with conventional antituberculosis drugs in treatment of tuberculosis (TB) in Uganda, there is paucity of knowledge on their combination effect. Aim: This research aimed to determine combination activity of standard antituberculosis drugs with extracts of Zanthoxylum leprieurii Guill. & Perr. and Rubia cordifolia L., the two common antituberculosis medicinal plants in Uganda, against pansensitive (H37Rv) and multi-drug resistant (MDR) Mycobacterium tuberculosis strains. Materials and Methods: Two reference MTB strains (H37Rv and MDR strain) were inoculated on Middlebrook 7H11 medium containing a combination of standard antituberculosis drugs and methanol extracts of Z. leprieurii and R. cordifolia at varying concentrations. The number of colonies on the plates was observed and counted weekly for up to 8 weeks. In vitro combination activity was determined using proportion method. Mean percentage inhibition was calculated for the reduction of number of colonies on drug-extract combination medium in relation to drug-extract-free control medium. Results: Drug-extract combinations showed good combination activity against Mycobacterium tuberculosis strains when compared with individual standard anti-TB drugs. This was more exhibited against MDR strain. There was however a reduction in percentage inhibition when extracts were combined with ethambutol and streptomycin against H37Rv strain. Conclusions: Zanthoxylum leprieurii and Rubia cordifolia in combination with standard anti-TB drugs exhibited increased in vitro activity against Mycobacterium tuberculosis, especially MDR-TB strain. This justifies the local use of these plants in traditional treatment of tuberculosis especially in resistant cases in Uganda.
文摘This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and ferric thiocyanate lipid peroxidation antioxidant assays were performed. High performance liquid chromatography was used to identify phenolic acids. There was no solvent effect on TPC nor on scavenging activities, and inhibition of lipid peroxidation (p > 0.05) among solvent extracts. On the other hand, 1:1:3 water: acetone: methanol extract (10.22 mg GAE/g sample) had significantly higher reducing potential than 50% ethanol extract (EE) (9.259 mg GAE/g sample) (p < 0.05);but EE was not significantly different from 80% methanol extract (9.781 mg GAE/g sample) (p > 0.05). Phenolic fraction designated as fraction 4 had the highest antioxidant activity (p < 0.05) with 69.49% ABTS scavenging activity and FRAP reducing potential, 22.26 mg of GAE/g sample. DPPH scavenging activities of fractions 4 (55.59%) and 5 (55.64%) were significantly higher than the other fractions (p A. rigidula extracts contain gallic, caffeic, vanillic, p-coumaric, salicylic acids and vanillin.
基金the Key Project of the Natural Science Foundation of Ningxia Hui Autonomous Region,China(2022AAC02020)the Major Strategic Research Project of the Chinese Academy of Engineering and Local Cooperation(2021NXZD8)the Key Research and Development Plan Project of Ningxia Hui Autonomous Region,China(2022004129003).We are grateful to the editors and anonymous reviewers for their insightful comments and suggestions in improving this manuscript.
文摘It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica var.gobica,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,China.We recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July 2023.Soil samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme activities.The results showed that the plant coverage and aboveground biomass of S.laricifolia community were significantly higher than those of C.tragacanthoides,S.breviflora,and S.tianschanica var.gobica communities(P<0.05).Soil enzyme activities varied among different plant communities.In the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in E.rhytidosperma and S.tianschanica var.gobica communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the subsoil.Specifically,the content of POC in the topsoil was 18.17%–42.73%higher than that in the subsoil.The structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and MAOC.The soil pH inhibited the formation of POC and promoted the formation of MAOC.Conversely,SWC stimulated POC production and hindered MAOC formation.Our study aimed to gain insight into the effects of desert plant communities on soil enzyme activities and SOC fractions,as well as the drivers of SOC fractions in the proluvial fan in the eastern foothills of the Helan Mountain and other desert ecosystems.
基金the 2021 Key Project of Natural Science and Technology of Yangzhou Polytechnic Institute,Active Disturbance Rejection and Fault-Tolerant Control of Multi-Rotor Plant ProtectionUAV Based on QBall-X4(Grant Number 2021xjzk002).
文摘With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance.
基金financially supported by the Third Xinjiang Comprehensive Scientific Expedition (2022xjkk020605)the Xinjiang Uygur Autonomous Region Regional Coordinated Innovation Project (Shanghai Cooperation Organization Science and Technology Partnership Program) (2020E01047)supported by the Introduction Project of High-level Talents in Xinjiang Uygur Autonomous Region, China
文摘Endophytes,as crucial components of plant microbial communities,significantly contribute to enhancing the absorption of nutrients such as nitrogen and phosphorus by their hosts,promote plant growth,and degrade pathogenic fungal mycelia.In this study,an experiment was conducted in August 2022 to explore the growth-promoting potential of endophytic bacterial strains isolated from two medical plant species,Thymus altaicus and Salvia deserta,using a series of screening media.Plant samples of Thymus altaicus and Salvia deserta were collected from Zhaosu County and Habahe County in Xinjiang Uygur Autonomous Region,China,in July 2021.Additionally,the inhibitory effects of endophytic bacterial strains on the four pathogenic fungi(Fusarium oxysporum,Fulvia fulva,Alternaria solani,and Valsa mali)were determined through the plate confrontation method.A total of 80 endophytic bacterial strains were isolated from Thymus altaicus,while a total of 60 endophytic bacterial strains were isolated from Salvia deserta.The endophytic bacterial strains from both Thymus altaicus and Salvia deserta exhibited plant growth-promoting properties.Specifically,the strains of Bacillus sp.TR002,Bacillus sp.TR005,Microbacterium sp.TSB5,and Rhodococcus sp.TR013 demonstrated strong cellulase-producing activity,siderophore-producing activity,phosphate solubilization activity,and nitrogen-fixing activity,respectively.Out of 140 endophytic bacterial strains isolated from Thymus altaicus and Salvia deserta,104 strains displayed anti-fungal activity against Fulvia fulva,Alternaria solani,Fusarium oxysporum,and Valsa mali.Furthermore,the strains of Bacillus sp.TR005,Bacillus sp.TS003,and Bacillus sp.TSB7 exhibited robust inhibition rates against all the four pathogenic fungi.In conclusion,the endophytic bacterial strains from Thymus altaicus and Salvia deserta possess both plant growth-promoting and anti-fungal properties,making them promising candidates for future development as growth-promoting agents and biocontrol tools for plant diseases.
文摘Tuberculosis (TB) remains a public health challenge and one of the leading causes of death worldwide. TB is preventable and curable. However, treatment of tuberculosis has continued to be difficult as a result of rapid increase of multidrug and extensively drug resistant strains of Mycobacterium tuberculosis. Medicinal plants have for centuries been traditionally used in treatment of tuberculosis and similar ailments. They possess antimicrobial properties which render them a new hope as a source of novel bioactive leads in the development of antimycobacterial agents. In this study, 2 plant species commonly used traditionally in Uganda for treatment of tuberculosis, Zanthoxylum leprieurii and Rubia cordifolia were screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis strains;pan sensitive MTB H37Rv, Rifampicin resistant TMC 331 strain and two wild strains (one rifampicin resistant and another one rifampicin susceptible). Antimycobacterial activity of aqueous, ethanolic and methanolic plant extracts was determined using Resazurin Microtiter Assay (REMA). Both plant extracts exhibited significant in vitro antimycobacterial activity against all strains of Mycobacterium tuberculosis. Minimum inhibitory concentrations (MIC) of methanolic crude extracts of both plants ranged from 23.4 μg/mL to 187.5 μg/mL. Comparatively, methanol extracts of both plants possessed superior antimycobacterial activity against all Mycobacterium tuberculosis strains. Our findings indicated that both plants exhibited activity against susceptible and resistant strains of Mycobacterium tuberculosis. While antimycobacterial activity of Z. leprieurii confirms results from previous studies, activity of the extracts of R. cordifolia is reported for the first time in East Africa. Further studies aimed at determining the effects of combination of these plant extracts and standard anti-TB drugs should be carried out.
基金Supported by Key Project from National Spark Plan,China(2012GA820001)Special Project of Guizhou Provincial Science and Technology,China[Qiankehe Special Project(2011)6001)]+1 种基金"321"Efficient Planting Technique Integration and Demonstration of Vegetable from Technology Ombudsman,China[(2013)6061-1)]Guizhou Vegetable Industry Technique System Construction Program,China(GZCYTX2011-0101)~~
文摘To investigate the effects of different vegetable growing regions and planting modes on soil quality,soils in high,medium and low altitude areas of Guizhou were respectively sampled under different vegetable efficient planting modes,and the variations of soil microbial flora and enzyme activities were analyzed. The soil microbial count and total bacteria of the vegetable efficient cultivation mode were significantly higher than that of the control (traditional planting mode) in each planting area,and the microbial diversity index was also improved to varying de- grees.The soil phosphatase,catalase and urease activities of the vegetable efficient planting mode were higher than that of the control.The soil catalase and urease activities were higher than that of the control by 1.37-1.44 and 1.51-2.80 times. Application of vegetable efficient planting mode in different regions will help to im- prove the soil quality in a given period.
文摘Objective:To assess the antibacterial activity of eight Iranian plant extracts against Staphylococcus aureus(S.aureus) strains which were isolated from infected patients.Methods: The studied strains were isolated from urine,stool,blood and wound of infected patients and identified by biochemical tests.In further,the antibacterial activity of 8 ethanolic local plant extracts including Querqus brantii(Q.brantii),Ziziphus spina-christi(Z.spina-christi),Peganum harmala(P.harmala),Oliveira decumbens(O.decumbens),Galium tricornutum(G.tricornutum), Vitex pseudo negundo(Vi.pseudo negundo),Salvia officinalis(S.officinalis),Vaccaria pyramidata (V.pyramidata) were then evaluated using agar disc diffusion method.Results:A total of 9 isolates were isolated and identified as S.aureus.Antibacterial profile of the strains showed that the strains were resistant to methicillin and cefixime.The highest antibacterial activity against the studied strains were belong to Q.brantii,P.harmala,Z.spina-christi and O.decumbens vent extracts with 11-40 mm,15-28 mm,8-26 mm and 10-20 mm of diameters,respectively. Intermediate antibacterial activity was exhibited by G.tricornutum and Vi.pseudo negundo against some of the studied strains with 7-20 mm and 7-13 mm of diameters,respectively. Noteworthy,out of 9 studied strains;6 and 2 of them were resistant to the G.tricornutum and Vi. pseudo negundo extracts,respectively.The S.officinalis and Va.pyramidata,however,showed no antibacterial activity against the studied strains.Conclusions:The Q.brantii,P.harmala,Z. spina-christi and O.decumbens extracts were shown to possess strong antibacterial activity against methicillin and cefixime resistant S.aureus strains and can be considered as the promising natural antibiotics for treating the studied strains.
文摘Objective:To evaluate the larvicidal and repellent activities of ethyl acetate and methanol extracts of Acacia concinna(A.concinna),Cassia siamea(C.siamea).Conundrum sativum(C. sativum),Cuminum cyminum(C.cyminum),Lantana camma(L.camara),Nelumbo nucifera (N.nucifera) Phyllanlhus amarus(P.amarus).Piper nigrum(P.nigrum) and Trachyspermum ammi(T.ammi) against Anopheles stephensi(An.stephensi) and Culex quinquefasciatus(Cx. quinquefasciatus).Methods:The larvicidal activity of medicinal plant extracts were tested against earl) fourth-instar larvae of malaria and filariasis vectors.The mortality was observed 24 h and 48 h after treatment,data were subjected to probit analysis to determine the lethal concentrations(LC<sub>50</sub> and LC<sub>90</sub>) to kill 50 and 90 per cent of the treated larvae of the tested species. The repellent efficacy was determined against two mosquito species at five concentrations(31.25. 62.50.125.00.250.00,and 500.00 ppm) under the laboratory conditions.Results:All plant extracts showed moderate effects after 24 h and 48 h of exposure;however,the highest activity was observed after 24 h in the leaf methanol extract ol N.nucifera.seed ethyl acetate and methanol extract of P.nigrum against the larvae of An.Stephensi(LC<sub>50</sub> = 34.76.24.54 and 30.20 ppm) and against Cx.quinquefasciatus(LC<sub>50</sub>= 37.49.43.94 and 57.39 ppm),respectively.The toxic effect of leaf methanol extract of C.siamea,seed methanol extract of C.cyminum,leaf ethyl acetate extract of N.nucifera.leaf ethyl acetate and methanol extract of P.amarus and seed methanol extract of T.ammi were showed 100%mortality against An.stephensi and Cx.quinquefasciatus alter 48 h exposer.The maximum repellent activity was observed at 500 ppm in methanol extracts of N. nucifera.ethyl acetate and methanol extract of P.nigrum and methanol extract of T.ammi and the mean complete protection time ranged from 30 to 150 min with the different extracts tested. Conclusions:These results suggest that the leaf and seed extracts of C.siamea.N.nucifera.P. amarus.P.nigrum and T.ammi have the potential to be used as an ideal ecofriendly approach for the control of the An.stephensi and Cx.quinquefasciatus.
基金supported by the Chongqing Science & Technology Commission,China (2005BA1014)the Chongqing Education Commission,China (KJ060302)
文摘The beet armyworm,Spodoptera exigua (Lepidoptera:Noctuidae),is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citrus crops.In this study,performance and subsequent enzyme activity of beet armyworm reared on host plants from five families were investigated.Significant differences were found in development,fecundity and enzyme activity on different host plants.Survival rate was the highest (42.8%) on asparagus lettuce (Lactuca sativar var.asparagina) and the lowest (17.0%) on sweet pepper (Capsicum annuum).Larval duration was the shortest on asparagus lettuce (12.0 d),and was 43.4% longer on sweet peppers (21.2 d).The activity of acetylcholine esterase (AChE) and carboxylesterase (CarE) in 3rd instar larvae,and soluble carbohydrate and crude protein contents in different host plants were determined.AChE activity was the highest in the larvae feeding on Chinese cabbage (Brassica rapa),but declined by nearly 60% on maize (Zea mays) seedlings.The ratio of soluble carbohydrate content to crude protein content in host plants was found to have a positive effect on oviposition and a negative correlation with larval duration and life time (from larval to adult stages) of the insect.
基金funded by the National Key Technology R&D Program(2015BAD09B0203)the National Basic Research Program of China(973 Program,2012CB416904)by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘To improve the productivity of poplar planta- tions, a field experiment of split-plot design with four tree spacings and three poplar clones was established, and four soil enzyme activities and microbial biomass were monitored in the trial. Soil enzyme activities, in most cases, were significantly higher in topsoil (0-10 cm) than in lower horizons (10-20 cm). Soil cellulase, catalase and protease activities during the growing season were higher than during the non-growing season, while invertase activity followed the opposite trend. Soil invertase, cellulase and catalase activities varied by poplar clone but soil protease activity did not. Cellulase and protease activities in the plantation at 5 × 5 m spacing were significantly higher than in the other spacings. The highest catalase activity was recorded at 6 × 6 m spacing. At the same planting density, invertase activity was greater in square spacings than in rectangular spacings. Soil microbial biomass was also significantly affected by seedling spacing and poplar clone. The mean soil MBC was significantly lower in topsoil than in the lower horizon, while MBN showed the opposite pattern. Significantly positive correlations were observed among soil cellulase, protease and catalase activities (p 〈0.01), whereas soil invertase activity was negatively and significantly correlated with cellulase, protease and catalase activities (p 〈 0.01). Soil microbial biomass and enzyme activities were not correlated except for a significantly negative correlation between soil MBC and catalase activities. Variations in soil enzyme activity and microbial biomass in different poplar plantations suggest that genotype and planting spacing should be considered when modeling soil nutrient dynamics and managing for long-term site productivity.
基金Under the auspices of National Natural Science Foundation of China(No.41571078,41171072)Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains,Ministry of Education
文摘As one of the most sensitive regions to global climate change, alpine tundra in many places around the world has been undergoing dramatic changes in vegetation communities over the past few decades.Herbaceous plant species in the Changbai Mountains area have significantly expanded into tundra shrub communities over the past 30 yr.Soil microbial communities, enzyme activities, and soil nutrients are intertwined with this expansion process.In order to understand the responses of the soil microbial communities to such an expansion, we analyzed soil microbial community structures and enzyme activities in shrub tundra as well as areas with three different levels of herbaceous plant expansion.Our investigation was based on phospholipid fatty acid(PLFA) analysis and 96-well microtiter plates.The results showed that herbs have expanded greatly in the tundra, and they have become the dominant species in herbaceous plant expansion areas.There were differences for community composition and appearance among the shrub tundra and the mild expansion, moderate expansion, and severe expansion areas.Except for soil organic matter, soil nutrients were increased in herbaceous plant expansion areas, and the total nitrogen(TN), total phosphorus(TP), available nitrogen(AN), and available phosphorus(AP) were greatest in moderate expansion areas(MOE), while soil organic matter levels were highest in the non-expanded areas(CK).The total soil PLFAs in the three levels of herbaceous plant expansion areas were significantly higher than those in the non-expanded areas, and total soil PLFAs were highest in the moderately expanded area and lowest in the severely expanded area(SEE).Bacteria increased significantly more than fungi and actinomycetes with herbaceous plant expansion.Soil hydrolase activities(β-1,4-glucosidase(βG) activity, β-1, 4-N-acetylglucosaminidase(NAG) activity, and acid phosphatase(aP) activity) were highest in MOE and lowest in the CK treatment.Soil oxidase activities(polyphenol oxidase(PPO) activities and peroxidase(PER) activities) were also highest in MOE, but they were lowest in the SEE treatment.The variations in total soil PLFAs with herbaceous plant expansion were mostly correlated with soil organic matter and available phosphorus concentrations, while soil enzyme activities were mostly correlated with the total soil nitrogen concentration.Our results suggest that herbaceous plant expansion increase the total soil PLFAs and soil enzyme activities and improved soil nutrients.However, soil microorganisms, enzyme activity, and nutrients responded differently to levels of herbaceous plant expansion.The soil conditions in mild and moderate expansion areas are more favorable than those in severe expansion areas.
基金Ethiopian Ministry of Science and Technology research and development grant FVS/11/2008
文摘Objective:To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis,wound and gastrointestinal complications.Methods:Hydroalcoholic exctracts of medicinal plants namely,Achyranthes aspera(A.aspera) L.(Family Asparagaceae),Ficus caria(F.caria)(Family Moraceae).Malvi parviflora(M.parviflora)(Family Malvaceae),Vernonia species(V.species) docal name Alakit.Family Asteraceae),Solatium hastifolium(S.hastifolium)(Family Solanaceae),Calpurinia aurea(C.aurea)(Ait) Benth(Family Fabaceae),Nicotiana tabacum(N.tabacum) L.(Family Solanaceae),Ziziphus spina-christi(Z.spina-christi)(Family Rhamnaceae).Croton macroslachys(C.macrostachys)(Family Fuphorhiaceae).were screened against clinical bacterial isolates of veterinary importance from October 2007 to April2009.The antibacterial activity was tested using disc diffusion at two concentrations(200 mg/mL and 100 mg/mL) and broth dilution methods using 70%methanol macerated leal extracts.Results:With the exception ol S.hastifolium all plant extracts exhibited antibacterial activity.Among the medicinal plants tested C.aurea.C.macrostachyus,A.aspera,N.tabacum and vcrnonia species(Alakit) showed the most promising antimicrobial properties.Conclusions:It can be concluded that many of the tested plants have antibacterial activity and supports the traditional usage of the plants for mastitis,wound and gastrointestinal complications treatment.Further studies into their toxicity and phytochemistry is advocated.
文摘More than 50% of the world population is infected with Helicobacter pylori (H. pylori). The bacterium highly links to peptic ulcer diseases and duodenal ulcer, which was classified as a group I carcinogen in 1994 by the WHO. The pathogenesis of H. pylori is contributed by its virulence factors including urease, flagella, vacuolating cytotoxin A (VacA), cytotoxin-associated gene antigen (Cag A), and others. Of those virulence factors, VacA and CagA play the key roles. Infection with H. pylori vacA-positive strains can lead to vacuolation and apoptosis, whereas infection with cagA-positive strains might result in severe gastric inflammation and gastric cancer. Numerous medicinal plants have been reported for their anti-H. pylori activity, and the relevant active compounds including polyphenols, flavonoids, quinones, coumarins, terpenoids, and alkaloids have been studied. The anti-H. pylori action mechanisms, including inhibition of enzymatic (urease, DNA gyrase, dihydrofolate reductase, N-acetyltransferase, and myeloperoxidase) and adhesive activities, high redox potential, and hydrophilic/hydrophobic natures of compounds, have also been discussed in detail. H. pylori-induced gastric inflammation may progress to superficial gastritis, atrophic gastritis, and finally gastric cancer. Many natural products have anti-H. pylori-induced inflammation activity and the relevant mechanisms include suppression of nuclear factor-κB and mitogen-activated protein kinase pathway activation and inhibition of oxidative stress. Anti-H. pylori induced gastric inflammatory effects of plant products, including quercetin, apigenin, carotenoids-rich algae, tea product, garlic extract, apple peel polyphenol, and finger-root extract, have been documented. In conclusion, many medicinal plant products possess anti-H. pylori activity as well as an anti-H. pylori-induced gastric inflammatory effect. Those plant products have showed great potential as pharmaceutical candidates for H. pylori eradication and H. pylori induced related gastric disease prevention.
文摘Objective:To evaluate the mosquito larvicidal activity of plant extracts.Methods:The hexane,chloroform,ethyl acetate,acetone,and methanol leaf,flower and seed extracts of Abrus precatorius(A.precatorius),Croton bonplandianum(C.bonplandianum),Cynodon dactylon (C.dactylon),Musa paradisiaca(M.paradisiaca) and Syzygium aromaticum(S.aromaticum) were tested against fourth instar larvae of Anopheles vagus(An.vagus),Armigeres subalbatus (Ar.subalbatus) and Culex vishnui(Cx.vishnui).Results:The highest larval mortality was found in seed ethyl acetate extracts of A.precatorius and leaf extracts of C.bonplandianum, flower chloroform and methanol extracts of M.paradisiaca,and flower bud hexane extract of S. aromaticum against An.vagus with LC<sub>50</sub> values of 19.31,39.96,35.18,79.90 and 85.90μg/mL;leaf ethyl acetate and methanol extracts of C.dactylon,flower methanol extract of M.paradisiaca, flower bud methanol extract of S.aromaticum against Ar.subalbatus with LC<sub>50</sub> values of 21.67, 32.62,48.90 and 78.28μg/mL,and seed methanol of A.precatorius,flower methanol extract of M.paradisiaca,flower bud hexane extract of S.aromaticum against Cx.vishnui with LC<sub>50</sub> values of 136.84,103.36 and 149.56μg/mL,respectively.Conclusions:These results suggest that the effective plant crude extracts have the potential to be used as an ideal ecofriendly approach for the control of disease vectors.This study provides the first report on the larvicidal activity of crude solvent extracts of different mosquitoes.
基金This study was financially supported by the Autonomous Foundation of Key Laboratory of Ethnomedicine (Minzu University of China), Ministry of Education (No. KLEM-ZZ201902)the National Natural Science Foundation of China Grants (No. 81973977)the National Training Programs of Innovation and Entrepreneurship for Undergraduates (No. GCYS2018110001).
文摘Flavonoids are natural organic compounds that are widely found in nature, their structural types are complex, and they mainly include flavonoids, flavonols, dihydroflavonols, isoflavones, dihydroisoflavones, chalcones, orange ketones, flavanoids, anthocyanidins, and biflavonoids. This review covers the plant distribution and pharmacological activities of flavonoids. Flavonoids are mainly distributed in angiosperms and gymnosperms, and they are abundant in plants such as Rutaceae, Labiatae, Zingiberaceae, Scrophulariaceae, and Leguminosae. Because of their wide distribution and variety, researchers have found that flavonoids have diverse biological activities, mainly focusing on anti-inflammatory, antibacterial and antitumor activities. Mechanistically, the anti-inflammatory effects are mainly related to the NF-κB and MAPK (mitogen-activated protein kinase) signaling pathway and then the inhibition of the production of inflammatory cytokines and mediators. The antibacterial activity is mainly manifested as inhibitory effects on many strains, including Escherichia coli, Cryptococcus neoformans, and Pseudomonas aeruginosa, via destroying the stability of the microbial membrane, inhibiting the invasion of virulent bacteria into host cells, promoting the apoptosis of bacteria, inhibiting bacterial fatty acid synthesis, etc. The antitumor activity of flavonoids is related to their inhibition of cell proliferation and induction of apoptosis via the mitochondria-mediated, endoplasmic reticulum-mediated, and death factor and its receptor-mediated signal transduction pathways. Understanding the plant distribution and pharmacological activity of flavonoids not only reveals the importance of identifying such valuable flavonoids in another genus or family but also provides a basis for fully exploiting the therapeutic potential of flavonoids.
基金supported by the Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Guangxi Normal University,China),Ministry of Education of China (07109001-11)Guangxi Natural Science Fund Project,China (0991097)
文摘Acorus tatarinowii Schott is a traditional Chinese medicine plant and has multiple bioactivities in medicine and pesticide field. In this study, the antifungal compound 1,2-dimethoxy-4(2-propenyl) benzene was isolated from A. tatarinowii Schott by activity-directed isolation method, and the inhibitory activity of the extract and 1,2-dimethoxy-4(2-propenyl) benzene against seven plant pathogenic fungi was evaluated. The results showed that the extract and 1,2-dimethoxy-4(2- propenyl) benzene had high inhibitory activity against hyphal growth of Thielaviopsis paradoxa (de Seynes) V. Hohnel, Pestalotia mangiferae P. Henn., Fusarium oxysporum f. sp. niveum (E. F. Smith) Syn. et Hans., Alternaria alternate Tanaka, Colletotrichum musae (Berk et Curt) V. Arx, Sphaceloma fawcettii Jenk., and Mycosphaerella sentina (Fr.) Schroter. The EC50 values of extract were 1.6162, 1.6811, 1.1253, 3.5771, 1.7024, 2.2284, and 2.2221 g L^-1, respectively, and the EC50 values of 1,2-dimethoxy-4(2-propenyl) benzene were 0.1021, 0.0997, 0.0805, 0.1742, 0.1503, 0.1853, and 0.1924 g L^-1, respectively. 1,2-Dimethoxy-4(2-propenyl) benzene also inhibited spores germination of T. paradoxa (de Seynes) V. Hohnel and F. oxysporum f. sp. niveum (E. F. Smith) Syn. et Hans., with the inhibitory rates of 98.81 and 100% at a concentration of 0.4 g L^-1 after 8 h, respectively. 1,2-Dimethoxy-4(2-propenyl) benzene is a potential botanical antifungal agent for controling of plant fungal diseases.
文摘Plant material screening was performed to study anti-Helicobacter pylori activity in vitro using an agar diffusion method on Columbia blood agar. 33 substances, juices and plant extracts and 35 of their combinations were tested. Quince (Cydonia oblonga) juice demonstrated the strongest anti-H. pylori activity followed by cranberry juice. Con-centrated apple juice, plum, red currant, black chokeberry, raspberry and bilberry juice also showed significant activity. Green tea and apple pomace extract as well as sweet flag rhizome, ginger and wild bergamot extract, cherry syrup, red beet juice and whey did not exhibit anti-Helicobacter activity. Quince juice in combination with bilberry, black chokeberry, red currant juice, green tea, sweet flag rhizome or apple pomace extract as well as cranberry juice in combination with sweet flag rhizome extract demonstrated a synergistic effect on inhibition of H. pylori. The obtained results offer new perspectives for development of functional anti-Helicobacter food product(s) for dietary management of H. pylori infection. The essential components of these products could be the most active juices and extracts like quince and cranberry juice supplemented with a corresponding synergist. Further studies are required to investigate the mechanism of antibacterial action of plant products and their efficacy in vivo.
文摘Leishmaniasis is considered as an emerging, uncontrolled disease and is endemic in 98 countries. Annually, about 2 million cases of cutaneous and 500000 cases of visceraltype leishmaniasis are recorded and 60000 persons died from the disease. In Mexico,cutaneous leishmaniasis is known as chiclero's ulcer and is reported in 22 states, it is considered as a health problem. For its treatment, pentavalent antimonial drugs are administered. These drugs cause severe side effects, are costly. Drug-resistant cases have been reported and have been developing for over 70 years. One alternative to the drugs that are currently available is to find active molecules in medicinal plants. Dihydrocorynantheine, corynantheine and corynantheidine are active against Leishmania major,while harmane, pleiocarpin, buchtienin, luteolin and quercetin are active against Leishmania donovani. In Mexico, about 20 medicinal plants have been evaluated against Leishmania mexicana, among which the most active are Tridax procumbens, Lonchocarpus xuul and Pentalinon andrieuxii. From these plants, active compounds with IC_(50)≤30 mg/mL or m M have been isolated, such as 3(S)-16,17-didehydrofalcarinol or Oxylipin, cholestra-4,20,24-trien-3-one or pentalinosterol, 24-methylcholest-4-24(28)-dien-3-one, cholest-4-en-3-one, 6,7-dihydroneridie-none, neridienone, cholest-5,20,24-trien-3β-ol, and isocordoin. Today, only pentalinonsterol has been synthesized and assayed in the visceral leishmaniasis experimental model using BALB/c mice infected with Leishmania donovani. Liposome formulation of this compound administered by intravenous route at 2.5 mg/kg showed a significant reduction of parasite load in mouse liver and spleen.
文摘Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was the highest among the plants. Ruta chalepensis had high levels of fat and carbohydrates (4.2% and 51.7%, respectively), but had the lowest level of ash (8.7%). Mineral concentrations varied and found to have appreciable amounts of Ca, Na, K, Cu, Fe, Mg, Mn, Zn and P. Total phenolic ranged from 163.1 (Tetragonolobus palaestinus) to 1328.8 mg GAE/100g (Ruta chalepensis). Anthocyanins ranged between 18.1 (Gundelia tournefortii) and 100.1 mg/100g (Rumex acetosella). These plants differed in free radical scavenging activity. It was concluded that these plants could be considered as natural sources for antioxidants and valuable natural resources as a new addition to the diet of inhabitants.