Larvicidal activities of hydro-ethanolic extracts of three Cameroonian medicinal plants against Aedes albopictus

Objective: To investigate the larvicidal activity of Syzygium guineense(Myrtaceae)(S. guineense), Monodora myristica and Zanthoxylum heitzii(Rutaceae)(Z. heitzii) extracts against Aedes albopictus(Ae. albopictus).Methods: The larvicidal activity of the hydro-ethanolic extracts from these plant species was assessed at three different concentrations(50, 100 and 200 mg/L) on first-instar of Ae. albopictus larvae in comparison with untreated controls. Mortality rate was recorded daily for a period of 12 days. The values of LC_(50) and lethal time killing 50% of the tested individuals(LT_(50)) were calculated using the log-probit analysis.Results: The root extract of S. guineense exhibited the best activity with 100% mortality after 8 days of treatment at 200 mg/L, followed by the fruit extract of Z. heitzii with83.33% mortality at the same concentration. Nonetheless, larvae were most susceptible to the fruit extract of Z. heitzii both in terms of LC_(50)(39.89 mg/L) and LT_(50)(145.68 h). A statistically significant difference between the control and the group treated at 200 mg/L was noticed in all the extracts.Conclusions: The present study shows that the hydro-ethanolic extracts of S. guineense,Monodora myristica and Z. heitzii tested have significant larvicidal activity. These preliminary results are of great interest and some of these plant species can be proposed for the formulation of new bioinsecticides to control Ae. albopictus populations.

Natural products and extracts from plants as natural UV filters for sunscreens:A review

Although solar exposure is necessary for human health,phototoxicology induced by excessive UVB and UVA radiation,which involves sunburns,skin aging and even tu-morigenesis,has been widely researched.Sunscreen is one of the most important ways to protect skin from UV phototoxic damage.As well as inorganic and organic UV filters,some natural products or plant extracts with aromatic rings in their structures,such as flavonoids or polyphenols,can absorb UV to reduce sunburn,acting as a natu-ral UV filter;they also show antioxidant or/and anti-inflammatory activity.This could explain why,although there are no officially approval natural commercial sun-filters,more and more commercial sunscreen products containing plant extracts are avail-able on the market.Here we summarize articles focusing on natural UV filters from plant published in the last 6 years,selecting the most significant data in order to better understand the photoprotective activity of natural products and extracts from plants,including their major constituents and main biological effects,methods for evaluating UV radiation resistance,anti-UV radiation experimental models and anti-UV radiation mechanisms.

Lethal and Sublethal Effects of Leaves Extracts from Native and Exotic Plants in Southern Brazil against Spodoptera frugiperda （Lepidoptera： Noctuidae） Caterpillars

The caterpillar Spodopterafrugiperda is an important pest of several crops, due to the damage it causes and the difficulty of its control. The method of controlling these pests is through chemical insecticides, which cause adverse effects to the biotic and abiotic environment. The selection of new insecticides that meet the requirements of efficacy, safety, selectivity and those are economically viable, is highlighting the study of mechanisms of plant defense. The present study aimed to verify the insecticide effect of 27 plants in three different types of plants extracts： aqueous, decoction and polypeptide on S. frugiperda. Three plants were chosen for performing sublethal effects bioassays： two plants with the highest corrected mortality （E. pulcherrima and R. simsii） and the other plant （Maytenus ilicifolia （espinheira santa）） with corrected mortality similar to control. In preliminaries bioassays, 25 plants showed corrected mortality less than 50%, according to Abbott＇s formula. R. simsii （azalea） and E. pulcherrima （billed parrot） showed 51% and 68% of corrected mortality, respectively. Only R. simsii aqueous and the three extracts of E. pulcherrima differ significantly from control （P 〈 0.05）. The aqueous extracts and decoction of R. simsii and polypeptide extract of E. pulcherrima reduced the larval period of S. frugiperda, different from control （P 〈 0.05）. The polypeptide extract of R. simsii reduced the pupal period of the target insect. The extracts obtained by decoction, aqueous and polypeptide of E. pulcherrima extracts and decoction of polypeptides and R. simsii affected the fertility and fecundity of S. frugiperda. For the other parameters, there is no significant difference when compared with the control. The results of this study suggest that the extracts obtained by decoction, aqueous and polypeptide of E. pulcherrima and R. simsii can be used to control S. frugiperda. However, the successful search, product starting from extracts of plants depends on the availability of plant and the entire assembly around the detection of bioactive products, in addition to the active ingredients of the chemical synthesis and elucidation of the target site insecticide molecule.

Evaluation of the Safety and Efficacy of Extracts from the Leaves of Five Plants Used for the Treatment of Arterial Hypertension in Benin

Cardiovascular diseases (CVD) are nowadays real health problems in the world. High blood pressure is one of the most important risk factors for CVD and is affecting more and more people in Benin. The objective of our work is to evaluate the safety and the efficacy of the leaves of five plants used for the treatment of hypertension in Benin. Acute toxicity was evaluated on wistar rats which orally administered a single dose of 2000 mg/kg of body weight of hydro-ethanolic extract of the leaves of Phyllanthus amarus Schumach. & Thonn., Persea americana MILL., Ipomoaea fistulosa Mart. ex Choisy., Heliotropium indicum L., Schrankia leptocarpa DC., and were monitored over a period of 14 days. Subacute toxicity was evaluated on rats which received a daily dose of 200 mg/kg of body weight of the plant leaf extract over a period of 28 days. Plant efficacy was assessed by measuring potassium in plant leaves. Administration of the single dose of the extract did not cause any deaths in rats;the weight of the rats varied depending on the extracts administered. Concerning the subacute treatment, the levels of aspartate amino transaminases (AST) and Alanine amino transaminases (AST) did not vary significantly after the 28 days of treatment with the different extracts. On the other hand, a significant increase in serum creatinine was observed in rats treated with extracts of Phyllanthus amarus. The leaves of Heliotropium indicum, Ipomoaea fistulosa and Phyllanthus amarus contain the highest levels of potassium. Among the five plants studied, only the leaves of Phyllanthus amarus seem to induce renal toxicity. Extracts from the leaves of Heliotropium indicum, Ipomoaea fistulosa might be the most effective in inducing hypotensive activity and do not show toxicity.

Effects of Plant Extracts Replacing Anticoccidial Drugs on Broiler Performance and Fecal Coccidia Count

[Objective]The paper was to investigate the impact of plant extracts replacing anticoccidial drugs on growth performance and fecal coccidia count in broilers.[Method]A total of 234 one-day-old healthy yellow-feathered broilers were selected and randomly divided into 3 groups,with 6 replicates in each group and 13 broilers in each replicate.The test lasted for a total of 55 d,The control group was fed the basic diet,the anticoccidial group was fed the basic diet+500 g/t dinitolmide,and the plant extract group was fed the basic diet+500 g/t plant extract.[Result]The daily gain of the plant extract group from 1 to 21 days of age was significantly higher than that of the anticoccidial drug group(P<0.05),and the feed/gain ratio was significantly lower than that of the anticoccidial drug group(P<0.05).There was no significant difference in daily gain and feed intake between the plant extract group and the anticoccidial drug group from 1 to 55 days of age(P>0.05),and the feed/gain ratio was reduced by 6.30%and the mortality and culling rate was reduced by 10.26%.The number of fecal coccidia at 33 days of age in the plant extract group was found to be significantly lower than that observed in the anticoccidial group and the control group(P<0.05).In conclusion,the administration of plant extracts resulted in a notable enhancement in the growth performance of chicks aged 1-21 days,when compared with the use of anticoccidial drugs.No significant difference was observed in growth performance between the plant extract and the anticoccidial drugs from 1 to 55 days of age.The administration of plant extracts resulted in a notable reduction in the fecal coccidia count.[Conclusion]Plant extracts may serve as viable alternatives to anticoccidial drugs and show promise for application in animal husbandry.

Assessing the Efficacy of Lemongrass (Cymbopogon citratus) and Sambong (Blumea balsamifera) Extracts in Combating Black Pod Disease: Sustainable Solutions for Controlling Phytophthora megakarya in Cameroon’s Cocoa Plantations

The use of plant extracts as antifungal agents is gaining increasing attention, particularly for the control of black pod disease in cocoa. Despite extensive research, current strategies haven’t been entirely effective. This study evaluated the effectiveness of Cymbopogon citratus and Blumea balsamifora leaf extracts, both individually and in combination, against Phytophthora megakarya. We assessed the efficacy of the most promising combination (75% B. balsamifera, 25% C. citratus) after storage at room temperature for up to 9 days. Agar microdilution and in vivo bioassays were conducted to determine antifungal susceptibility and effectiveness. Blumea extract exhibited the highest overall inhibitory activity, with the lowest minimum inhibitory concentration (117 µl mL−1) while C. citratus had a narrower range of MIC (146 to 233 µl mL−1). The combination of C. citratus and B. balsamifera demonstrated a synergistic effect against P. megakarya, achieving growth inhibition on V8 media (92.72 ± 4.20% to 100%) and on artificially infected detached pod cortex (92.24 ± 4.53% to 98.75 ± 1.25%), which was not significantly different from the positive control (Ridomil). Furthermore, this combination maintained its effectiveness for up to 9 days at room temperature. These findings suggest that combining plant extracts can enhance their antifungal properties.

Management of Strawberry Grey Mold Disease Using Biocontrol Agents and Plant Extracts

Strawberry (Fragaria × ananassa Duch.) is a significant global soft fruit crop, prized for its nutrient content and pleasant flavor. However, diseases, particularly grey mold caused by Botrytis cinerea Pers. Fr. poses major constraints to strawberry production and productivity. Grey mold severely impacts fruit quality and quantity, diminishing market value. This study evaluated five B. cinerea isolates from various locations in the Ri-Bhoi district of Meghalaya. All isolates were pathogenic, with isolate SGM 2 identified as highly virulent. Host range studies showed the pathogen-producing symptoms in the fava bean pods, marigold, gerbera, and chrysanthemum flowers and in the fava bean, gerbera, and lettuce leaves. In vitro tests revealed that neem extract (15% w/v) achieved the highest mycelial growth inhibition at 76.66%, while black turmeric extract (5% w/v) had the lowest inhibition at 9.62%. Dual culture methods with bio-control agents indicated that Bacillus subtilis recorded the highest mean inhibition at 77.03%, while Pseudomonas fluorescens had the lowest at 20.36% against the two virulent isolates. Pot evaluations demonstrated that B. subtilis resulted in the lowest percent disease index at 20.59%, followed by neem extract at 23.31%, with the highest disease index in the control group at 42.51%. Additionally, B. subtilis significantly improved plant growth, yielding an average of 0.32 kg compared to 0.14 kg in the control. The promising results of B. subtilis and neem leaf extract from this study suggest their potential for eco-friendly managing grey mold in strawberries under field conditions.

Antimicrobial Activities of Extracts of Macrosphyra longistyla against Gram-Positive Oral Biofilm-Formers from School Children in Southwestern Nigeria and Toxicity Studies Using Brine Shrimps

The world will benefit from more effective antimicrobial agents against oral conditions arising from the actions of biofilm forming bacteria. Also, information is lacking on the oral biofilm-forming bacterial diversity in Southwestern Nigeria. In this study, we isolate and characterize oral biofilm producing bacteria in the oral cavities of schoolchildren in Southwestern Nigeria. We also investigate the antimicrobial properties of Macrosphyra longistyla extracts against the biofilm-formers and the toxicity of potent extracts. Samples were obtained from 109 schoolchildren aged 4 - 14 years from Lagos, Oyo and Osun States. Agar well diffusion technique was used in the antimicrobial susceptibility testing. Toxicity testing was done using brine shrimps (Artemia salina). Biofilm-formers in this study are Klebsiella sp., Streptococcus sp., Staphylococcus sp., and Micrococcus sp. Ethanol leaf extracts had the highest activity against all biofilm-producing bacteria. Ethanol stem bark extract, which elicited activity against Klebsiella only, was found to be less toxic than the ethanol leaf extract. Staphylococcus showed >10 mm susceptibility to the ethanol and aqueous extracts of Macrosphyra longistyla. Streptococcus and Micrococcus were susceptible to the antimicrobial actions of the ethanolic leaf extracts. Although the ethanol extracts of the leaves had lower minimum inhibitory concentrations than the ethanol extracts of the stem bark, toxicity studies showed ethanol extracts of the stem-bark to be more toxic than the ethanol extracts of the leaves. In conclusion, ethanolic extracts of Macrosphyra longistyla show potential as sources of antimicrobials against gram-positive, oral biofilm-forming bacteria.

Inhibitory Effects of Some Plant Extracts on 5 Bacterial Strains

[Objective] This study was conducted to develop potential natural plant products for controlling walnut blight pathogen and other bacteria. [Method] Inhibitory effects of extracts obtained from 15 plants with 3 solvents on bacteria were investi- gated by disk diffusion method. [Results] Except the extracts from Magnolia grandi- flora and Typha orientalis, extracts of 13 plant leaves presented inhibitory effects on 5 bacteria strains to certain degrees. Among them, the effect of water extract of Aesculu schinensis on Bacillus sp. XHE8 was the strongest, with inhibition zone di- ameter reaching （31.3＋3.9） mm and the ratio to control above 5.0. Four of the 5 tested strains were sensitive to the extracts of Sambucus chinensis, and 3 of them were inhibited by Ophiopegon japonicas extracts and Reineckia camea extracts, with ratios of treatment to control large than 1.5 in all. Leaf extract of A. chinensis had significant anti-bacteria ability, and could be used as a potential plant source for bactericide. [Conclusion] The results laid a foundation for exploring active com- pounds and elucidating the mechanism in it.

Screening of Antioxidant Potential of Selected Barks of Indian Medicinal Plants by Multiple in vitro Assays

Objective To evaluate the antioxidant potential in herbal extract barks of five therapeutically important medicinal plants native to India, i.e. Crataeva nurvala Buch.-Ham., Buchanania lanzan Spreng., Aegle marmelos Corr., Dalbergia sissoo Roxb. ex DC., and Cedrela toona Roxb. Methods Standardized aqueous alcoholic extracts from the selected barks having different target radicals, such as superoxide radical, nitric oxide, ABTS radical, and peroxidative decomposition of phospholipids, were prepared and screened by multiple in vitro assays. These extracts were also tested for total phenolic and tannin content and correlated with antioxidant capacity. Results Total phenolic and tannin contents were found to be the highest in C. nurvala （195 GAE mg/g and 218.3 mg/g CE）. SOD mimetic activity was found to be the highest in Crataeva nurvula, although all barks showed activity more than IO3 units/mg extract. Lipid peroxidation inhibitory potential was found to be the highest in Crataeva nurvala （83.4% inhibition of MDA formation/10 μg extract）, and also showed a comparatively high NO quenching capacity （45.5% per 10 μg extract）. The highest NO quenching potential was found in Aegle marmelos （47.3% per 10 μg extract）. Cedrela toona showed the lowest LPO inhibitory potential and NO quenching capacity （50.5% and 30.5%, respectively）. Buchanania lanzan, a medicinal plant extensively used for inflammatory disorders and Dalbergia sissoo also showed 72.5% and 69.1% LPO inhibitory potential/10 μg extract. Trolox equivalent antioxidant capacity ranged from 0.24 to 0.39 mmol/L TEAC/mg extract, indicating that all the barks tested had ABTS^＋ radical quenching capacity. Conclusion Bark of Crataeva nurvula has the highest antioxidant capacity and a positive correlation between antioxidant activity and their plendic content was found.

Sperm immobilization activity of Allium sativum L. and other plant extracts

<abstract>Aim: To identify possible spermicidal agents through screening a number of edible medicinal plants with antimicrobial activity. Methods: Initial screening was made on the basis of ram cauda epididymal sperm immobilization immediately after addition of extracts. The most potent extract was selected and was evaluated on both ram and human spermatozoa. To unravel its mode of action several sperm functional tests were carried out, namely viability of cells, hypo-osmotic swelling test for membrane integrity and assays of membrane-bound enzyme 5'-nucleotidase and acrosomal marker enzyme acrosin. Results: The crude aqueous extract of the bulb of Allium sativum L. showed the most promising results by instant immobilization of the ram epididymal sperm at 0.25 g/mL and human ejaculated sperm at 0.5 g/mL. Sperm immobilizing effects were irreversible and the factor of the extract responsible for immobilization was thermostable up to 90 癈. On boiling at 100 癈 for 10 minutes, this activity was markedly reduced. Moreover, this extract was able to cause aggregation of ram sperms into small clusters after 30 minutes of incubation at 37 癈. However this property was not found in human spermatozoa. More than 50 % reduction in sperm viability and hypo-osmotic swelling occurred in treated sperm as compared with the controls, indicating the possibility of plasma membrane disintegration which was further supported by the significant reduction in the activity of membrane bound 5'-nucleotidase and acrosomal acrosin. Conclusion: The crude aqueous extract of A. sativum bulb possesses spermicidal activity in vitro.

Anti-Insect Activity of the Methanol Extracts of Fern and Gymnosperm

With environmental and food safety issues becoming one of the greatest concerns of the public, active plant compounds play more and more important roles in pest controlling. Fern to their particular status in plant taxology and co-evolution are of great significance for application as new pesticides due with insects. In this study, methanol extracts were distilled from wild fern and gymnosperm of 54 species of 22 families collected from Shiwandashan Mountain in Guangxi Zhuang Autonomous Region of China. Insecticidal activities of the methanol extracts were assayed on both adult house fly （Musca domestica） and mosquito （Aedes albopictus）. Significant insecticidal activities were exhibited in the methanol extracts of five species, Cupressusfunebris （leaves and stems）, Cycas acuminatissima （roots）, Keteleeria fortunei （leaves and stems）, Onychium japonicum （whole plant）, and Pinus taiwanensis var. Darning shanensis （leaves and stems）. Applications of the extracts of these plants resulted in higher than 50% mortalities in 4th instar larvae of A. albopictus at 24 h after treatment. The methanol extracts from 13 species possessed insecticidal activities against the adult of M. domestica at 48 h after treatment with higher than 90% mortalities. The extensive screening results showed that these fern and gymnosperm were highly potential to be botanical insecticides. The findings provide a feasible and valuable basis for further investigation.

The Control Efficiency of Plant Alcohol Extracts on the Laboratory Populations of Myzus persicae(Sulzer)and Lipaphis erysimi (Kaltenbach)

The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (IIPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr. Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant pro-tectant to protect crops.

Use of Support Vector Regression Based on Mean Impact Value Model to Identify Active Compounds in a Combination of Curcuma longa L.and Glycyrrhiza extracts

A support vector regression based on the mean impact value (MIV) model was constructed to identify the bioactive compounds inhibiting proliferation of HeLa cells in a combination of turmeric (Curcuma longa L.) and liquorice (Glycyrrhiza) extracts. The quantitative chemical fingerprint from 50 batches of turmeric and liquorice extracts was established using high performance liquid chromatography hyphenated to an ultraviolet visible detector. Qualitative results were obtained using ultra performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry. A total of 46 peaks (peaks 1–15 from turmeric and 16–46 from liquorice) were selected as “common peaks” for analysis. The inhibitory effect of the combined extracts on HeLa cells was measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. It was found that 15 compounds (peaks: 8, 12, 30, 24, 46, 11, 14, 9, 3, 1, 44, 18, 7, 45 and 43) possessing high absolute MIV exhibited a significant correlation with the cytotoxicity against HeLa cells; most of these have already been confirmed with potential cytotoxicity in previous research. The important potential application of the present model can be extended to help discover active compounds from complex herbal medicine prior to traditional bioassay-guided separation. It is considered that this could be a useful tool for re-developing herbal medicine based on the use of these active compounds. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

Effects of extracts from Hibiscus macranthus and Basella alba mixture on testosterone production in vitro in adult rat testes slices

Aim： To find an in vitro system for the measurement of the androgenic effects of different extracts of Hibiscus macranthus （Malvaceae） and Basella alba （Basellaceae）. Methods： The production of testosterone from testes slices incubated in two media, either Krebs-Henseleit buffer containing 0.5% Bovine serum albumin （BSA） or Dubecco＇s Modified Eagle＇s medium-F12 Ham nutrient mixture （DME/Ham F12）, under a mixture of 5% CO2 in 95% air was determined either in the presence or absence of cofactors and Hibiscus macranthus plus Basella alba （HMBA） extracts. Results： The testosterone production was increased in testes slices incubated in DME/Ham F12 medium in response to the cofactors （49%） and aqueous extracts （34%-60% according to dilutions）. Under the same atmospheric conditions, there was no positive response of the testes slices to either cofactor or HMBA extract stimulation in Krebs-Henseleit buffer containing 0.5% BSA, In further investigations related to the effect of HMBA, the DME/ Ham F12 medium was used. The results obtained from the in vitro test showed that the activity was present mainly in methylene chloride and methanol, since these extracts induced an increase in testosterone production by testes slices. Conclusion： The testes slice system is suitable to be used for further in vitro investigations of the isolation of androgenic bioactive components of plants. （Asian J Androl 2006 Jan; 8： 111-114）

Dietary plant extracts modulate gene expression profiles in alveolar macrophages of pigs experimentally infected with porcine reproductive and respiratory syndrome virus

Background: Our previous study showed that 3 plant extracts enhanced the immune responses and growth efficiency of weaned pigs infected with porcine reproductive and respiratory syndrome virus(PRRSV), which is one of the most economically important disease in swine industry. However, each plant extract differently effected on growth efficiency and immune responses. Therefore, the objective of this study was conducted to characterize the effects and investigate the potential underlying mechanisms of 3 plant extracts on gene expression of alveolar macrophages in weaned pigs experimentally infected with PRRSV.Results: PRRSV infection altered(P < 0.05) the expression of 1,352 genes in pigs fed the control(CON;755 up, 597 down). Compared with the infected CON, feeding capsicum(CAP), garlic botanical(GAR), or turmeric oleoresin(TUR) altered the expression of 46 genes(24 up, 22 down), 134 genes(59 up, 75 down), or 98 genes(55 up, 43 down) in alveolar macrophages of PRRSV-infected pigs, respectively. PRRSV infection up-regulated(P < 0.05) the expression of genes related to cell apoptosis, immune system process, and response to stimulus, but downregulated(P < 0.05) the expression of genes involved in signaling transduction and innate immune response.Compared with the infected CON, feeding TUR or GAR reduced(P < 0.05) the expression of genes associated with antigen processing and presentation, feeding CAP up-regulated(P < 0.05) the expression of genes involved in antigen processing and presentation. Supplementation of CAP, GAR, or TUR also enhanced(P < 0.05) the expression of several genes related to amino acid metabolism, steroid hormone synthesis, or RNA degradation, respectively.Conclusions: The results suggest that 3 plant extracts differently regulated the expression of genes in alveolar macrophages of PRRSV-infected pigs, especially altering genes involved in immunity.

Background correction in near-infrared spectra of plant extracts by orthogonal signal correction

In near-infrared (NIR) analysis of plant extracts, excessive background often exists in near-infrared spectra. The detection of active constituents is difficult because of excessive background, and correction of this problem remains difficult. In this work, the orthogonal signal correction (OSC) method was used to correct excessive background. The method was also compared with several classical background correction methods, such as offset correction, multiplicative scatter correction (MSC), standard normal variate (SNV) transformation, de-trending (DT), first derivative, second derivative and wavelet methods. A simulated dataset and a real NIR spectral dataset were used to test the efficiency of different background correction methods. The results showed that OSC is the only effective method for correcting excessive background.

Bioactivity of Four Plant Extracts on Coleopterous Pests of Stored Cereals and Grain Legumes in Nigeria

The efficacy of ethanol extracts from four plants, Dennettia tripetala Baker, Eugenia aromatica Baillon, Piper guineense Thonn et Schum and Anchomanes difformis P. Beauv. as bioinsecticides for control of adult Sitophilus zeamais Motschulsky, Tribolium castaneum Herbst, Callosobruchus maculatus Fabricius, Oryzaephilus mercator Fauvel and Lasioderma serricorne Fabricius were determined at two concentrations (0.5% and 2.0%) in the laboratory. All extracts were toxic to beetles with E. aromatica being the most potent of four plant materials tested and had the least LT 50 value. This was followed by A. difformis extract. At 2.0% v/w extract concentration, percentage grain damage by insects in treated grains stored for 90 days was nil. Grains protected with A. difformis had the least percentage seedgerminationof62.50%whilethoseprotectedwithP.guineensehadthehighestpercentagegermination(74.58%)at2.0% extract concentration. The mean percentage germination in the control was 72.72%. Treatment of grains with plant extracts had no significant (P>0.05) effect on its water absorption capacity.

Anti-quorum sensing and anti-biofilm formation activities of plant extracts from South Korea

Objective: To investigate anti-quorum sensing(anti-QS) and anti-biofilm formation(antiBF) activities of the ethanol extracts of 388 plants. Methods: The anti-QS activity of the plant extracts was evaluated by disc-diffusion assays using the bio-reporter strain, Chromobacterium violaceum CV017. Pseudomonas aeruginosa PAO1, Yersinia enterocolitica ATCC 9610, and Agrobacterium tumefaciens C58, which possess QS systems, were used to evaluate the antiBF activity of the plant extracts. Results: Among 388 plant extracts, the Cornus controversa(C. controversa) and Cynanchum wilfordii extracts exhibited the strongest anti-QS activity. The C. controversa extract exhibited anti-BF activity against Pseudomonas aeruginosa, Yersinia enterocolitica and Agrobacterium tumefaciens, whereas the Cynanchum wilfordii extract exhibited no anti-BF activity against Pseudomonas aeruginosa. In addition, the C. controversa extract suppressed soft rot of cabbage. Conclusions: The C. controversa extract inhibits bacterial QS and BF, and is capable of controlling soft rot. Therefore, this extract has potential for the prevention and treatment of bacterial infections and for the development of alternatives to antibiotics.

Anti-breast Cancer Agents Derived from Plants

Upon emergence of modern anticancer therapy,medical community is divided into two opposite camps,one of them claiming absolute necessity of using isolated or synthesized chemical compounds for efficient patient treatment and another one advocating alternative cancer therapies,in particular those based on natural sources,including extracts from plants.It seems,in reality,that the two camps are reconcilable:while natural sources,plant extracts or juices play both curative and protective role,drugs represent the ultimate possibility to inhibit or reverse tumor development.In this paper we tried to analyze anti-breast cancer potencies of quite a few extracts from different plant sources and to compare their anti-proliferative efficiency of crude extracts with actions of their purified ingredients.