期刊文献+
共找到34,792篇文章
< 1 2 250 >
每页显示 20 50 100
Effects of Incorporating Mango (Mangifera indica), Avocado (Persea americana) and Guava (Psidium guajava) Leaves Powder in the Ration on Growth Characteristics in Rabbits
1
作者 Emma Fortune Magloire Bend Hervé Tchoffo +2 位作者 Margaret Mary Momo Chongsi Meli Ivan Pavel Kouti Ferdinand Ngoula 《Food and Nutrition Sciences》 CAS 2024年第10期991-1003,共13页
A study conducted on burgundy rabbits evaluated the effects of rations containing mango (Mangifera indica), avocado (Persea americana) and guava (Psidium guajava) powder. For this purpose, 36 rabbits (20 males and 16 ... A study conducted on burgundy rabbits evaluated the effects of rations containing mango (Mangifera indica), avocado (Persea americana) and guava (Psidium guajava) powder. For this purpose, 36 rabbits (20 males and 16 females) aged 60 to 70 days with an average weight of 1012 ± 133 g were divided randomly into 4 equal groups (T0, T1, T2 and T3) of 9 animals each according to body weight (bw). The rabbits were divided throughout the trial, the animals were fed, those of group T0 (control) with a standard feed without any type of leaf powder, while those of groups 1, 2 and 3 received the standard feed supplemented with Mangifera indica, Persea americana and Psidium guajava leaves powder at the rate of 0.5% respectively. After two months of treatment, the animals were fasted for 12 hours (20 h - 8 h) and sacrificed to evaluate carcass and digestive organ weights. The results revealed that the values of feed intake, live weight and weight gain were non-significantly (p > 0.05) increased in all animals regardless of the ration in reference to the control. The different leaves powder induced an increase in carcass yield in rabbits but this increase was only significant (p M. indica leaf powder (51.03 ± 0.24) as compared to the control (48.63 ± 0.74). Gut length was significantly increased in animals fed rations containing Psidium guajava and Persea americana leaves powder compared to the control. A significant increase in gut weight was observed in animals fed the Persea americana leaf supplemented ration. In general, mango leaf powder performed better than other types of powders. 展开更多
关键词 AVOCADO Growth Characteristics leaves GUAVA MANGO Rabbit
下载PDF
Processing Effects on Selected Antioxidant Activities and Metabolizing Enzyme Inhibition of M. Koneigii (Curry Leaves) Extracts
2
作者 Karthik Medabalimi Rajwinder Kaur Martha Verghese 《Food and Nutrition Sciences》 CAS 2024年第6期470-483,共14页
Curry leaves, scientifically termed Murraya koenigii, are renowned in South Asian cuisine for their flavor enhancement and potential health benefits, including antioxidative, anti-inflammatory, and antidiabetic proper... Curry leaves, scientifically termed Murraya koenigii, are renowned in South Asian cuisine for their flavor enhancement and potential health benefits, including antioxidative, anti-inflammatory, and antidiabetic properties. This study aimed to evaluate the impact of thermal processing methods on curry leaves by analysing Total Phenolic Content (TPC), Total Flavonoid Content (TFC), antioxidant activity, and metabolizing enzyme inhibition. Fresh curry leaves were subjected to thermal treatments: Oven-dried at 60˚C and Air-dried at 25˚C for 2 weeks. Extracts were prepared using Ethanol and water solvents. Results indicated that Air-dried leaves exhibited significantly higher TPC (5132.65 mg GAE/100 g) and TFC (243.13 mg CE/100 g) compared to Fresh and Oven-dried leaves. Antioxidant assays show that oven-dried curry leaves at 60˚C displayed higher results in NORS, FRAP, and TEAC assays compared to Fresh and Air-dried leaves. Ethanol extracts showed better extraction of bioactive compounds than aqueous extracts. Moreover, Lipase inhibition activity was notably high, indicating potential health benefits. This study provides valuable insights into the effects of processing methods on curry leaf extracts, emphasizing the importance of solvent selection for optimal extraction of bioactive compounds. 展开更多
关键词 Murraya Koenigii Curry leaves ANTIOXIDANTS PHYTOCHEMICALS Metabolizing Enzymes
下载PDF
Effects of Carrot (Daucus carota) Leaves Powder on Reproductive and Growth Characteristics of Rabbit (Oryctolagus cuniculus) Does
3
作者 Margaret Mary Momo Chongsi Nienga Sorelle Deutcheu +6 位作者 Marie Noel Bertine Noumbissi Emma Fortune Magloire Bend Hervé Tchoffo Kelvin Nguatem Bertin Narcisse Vemo Tahir Markhous Adam Mahamat Ferdinand Ngoula 《Open Journal of Animal Sciences》 2024年第4期302-320,共19页
The present study was conducted to evaluate the effects of carrot leaf powder in the diet on reproductive and growth characteristics in rabbits. Thirty sexually matured rabbits does of 8 months old, 3.00 to 3.20 kg, w... The present study was conducted to evaluate the effects of carrot leaf powder in the diet on reproductive and growth characteristics in rabbits. Thirty sexually matured rabbits does of 8 months old, 3.00 to 3.20 kg, were divided into three groups of 10 rabbits each, which were comparable in terms of body weight. Throughout the experiment, the rabbits of group 1 (control group) were fed ad libitum with a feed not containing carrot leaf powder (control ration), while those of groups 2 and 3 received the control ration supplemented with carrot leaf powder in concentrations of 0.5% and 1% respectively. Data was collected on feed intake, weight gain, receptivity, fertility, gestation length of does, litter size, weight, viability and sex ratio of the young rabbits till 5 weeks post-partum. There was no significant (P > 0.05) difference in the fertility rate, gestation duration and sex ratio of the kits with reference to the control. Litter size at birth was not significantly (P > 0.05) influenced in does fed diets containing carrot leaf powder compared to the control. However, the reversed effects were observed at five weeks post-partum. The live weight of weaned kits and weight gain of rabbit does at birth were significantly (P < 0.05) increased in treated rabbits compared to the control. The supplementation of carrot leaf powder in feed can improve production performance in female rabbits, through their antioxidant activities thanks to their various components, thus fighting against oxidative stress effects to which animals are exposed both from endogenous and environmental sources. 展开更多
关键词 Antioxidant Carrot leaves Growth Rabbit Doe REPRODUCTION
下载PDF
Synthesis of reduced graphene oxide nanosheets from sugarcane dry leaves by two-stage pyrolysis for antibacterial activity
4
作者 Baskar Thangaraj Pravin Raj Solomon +4 位作者 Nutthapon Wongyao Mohamed I.Helal Ali Abdullah Sufian Abedrabbo Jamal Hassan 《Nano Materials Science》 EI CAS CSCD 2024年第5期625-634,共10页
Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is mad... Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is made on the dry leaves of sugarcane(Saccharum officinarum)as an alternative raw material so as to be economical and environmentally benign.The dry leaves are subjected to two-step pyrolysis without any catalyst or reducing agent in far divergent temperatures to produce as prepared and acid treated rGOs.They were evaluated by UV–Vis.,FTIR,XRD,Raman spectroscopy,TGA/DTG,BET,FESEM-EDS and TEM.The as prepared rGO has few layers with irregular and folded architecture whereas acid-treated rGO has thinly stacked crumpled sheets with many wrinkles on its surface.The prepared rGOs have multilayered graphitic structure due to the unique ratio between G and D bands.Acid treated rGO has poor thermal stability as compared to that of as-prepared rGO at high temperatures due to the variation in the oxygen-containing functional groups.Acid treated rGO has low antibacterial activity as compared to that of the as-prepared rGO due to the paucity of the functional groups. 展开更多
关键词 Biomass wastes Sugarcane dry leaves PYROLYSIS Reduced graphene oxide Antibacterial activity
下载PDF
Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America
5
作者 Zhihui Wang Philip A.Townsend +1 位作者 Eric L.Kruger Anna K.Schweiger 《Forest Ecosystems》 SCIE CSCD 2024年第5期728-742,共15页
Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental change.However,datasets with records of multi... Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental change.However,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade leaves.We presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 424 individuals of 110 plant species from 19 sites across eastern North America.We investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait expression.Generally,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific characteristics.Covariation between sun and shade leaf traits,and trait-environment relationships were overall consistent across species.The main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural traits.Taxonomy and canopy position collectively explained most of the foliar trait variation.This study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem functions.Our findings have implications for efficient field sampling,and trait mapping with remote sensing. 展开更多
关键词 Foliar traits Leaf trait variation Trait-environment covariation Shade leaves NEON Leaf spectroscopy
下载PDF
Influence of soaking Malus domeri(Bois)Chev.leaves on gut microbiota and metabolites of long-living elderly individuals in Hezhou city,Guangxi,China
6
作者 Hui Nie Zhongyang Gao +4 位作者 Yanghe Luo Yajuan Wang Feiyang Wu Guangqing Mu Xiaomeng Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1311-1321,共11页
To investigate the effects of drinking the soaking of Malus domeri(Bois)Chev.leaves on gut microbiota and metabolites of long-living elderly individuals in Hezhou city,Guangxi,China.It has been reported that longevity... To investigate the effects of drinking the soaking of Malus domeri(Bois)Chev.leaves on gut microbiota and metabolites of long-living elderly individuals in Hezhou city,Guangxi,China.It has been reported that longevity is closely related to metabolism and the gut microbiota.The 16S rRNA sequencing and liquid chromatography-mass spectrometry(LC-MS)were used to analysis fecal samples and explore the factors affecting longevity in the region.Interestingly,we discovered,that elderly individuals who had been drinking the soaking of M.domeri(Bois)Chev.leaves for a long time exhibited higher diversity of the gut microbiota than without drinking the soaking,notably.The proportions of Ruminococcaceae and Prevotella were decreased in those who did not drink this soaking.In addition,a total of 106 metabolites were characterized,and the people of long-lived people(>90 years old)and elderly people(<90 years old)who drinking soaking of M.domeri(Bois)Chev.leaves significantly altered the gut microbiota and upregulated levels of haplopine,farnesol,genipic acid,momordicinin,2-hydroxyestrone,hydroxyphenyllactic acid,caffeic acid,sophoraflavanone B,and soyasaponin I.We preliminarily determined that M.domeri(Bois)Chev.leaves consumption may be an important factor affecting longevity in this area. 展开更多
关键词 LONGEVITY Malus domeri(Bois)Chev.leaves Gut microbiota Metabolomics
下载PDF
The Protective Effects of Flavonoids from Scutellaria Baicalensis Georgi Stems and Leaves on Oligodendrocyte Damage Induced by Aβ1-42
7
作者 Tangtang Song Yinhui Yao Yazhen Shang 《Pharmacology & Pharmacy》 2024年第1期1-13,共13页
Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. ... Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ<sub>1-42</sub>, an injury model was established by subjecting OLN-93 cells to Aβ<sub>1-42</sub> exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ<sub>1-42</sub>. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ<sub>1-42</sub>-induced damage of OL. 展开更多
关键词 Flavonoids form the Stem and leaves of Scutellaria baicalensis Georgi 1-42 OLIGODENDROCYTES DAMAGE
下载PDF
Effects of Different Exogenous Substances on Seed Germination of Isatis indigotica Under Drought Stress and Chemical Composition of Isatis indigotica leaves
8
作者 Wang Hao Qin Jingjing +4 位作者 Shi Zhe Song Jiayao Ma Wuqiong Wang Huimin Cao Jinjun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第2期66-75,共10页
This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogeno... This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogenous substances to efficient cultivationof Isatis indigotica. Polyethylene glycol (PEG) was used to simulate drought stress to deal with seeds of Isatis indigotica at thegermination stage (concentration: 0, 10%, 15%, and 20%). Simultaneous operation of exogenous growth regulators [microbialinoculum (MI), γ-aminobutyric acid (GABA) and salicylic acid (SA)] and PEG were implemented in seeds of Isatis indigotica.The effects of drought stress and the mitigation of exogenous substances were observed by statistics of seed germination potential,germination rate, hypocotyl length, and radicle length of each treatment. The effects of exogenous substances on the content ofalkaloids, crude protein and free amino acids in the leaves of Isatis indigotica grown in a greenhouse were determined after sprayingexogenous substances on the plants. The differences of germination potential, germination rate, hypocotyl length, and radicle lengthamong 15% PEG stress treatment, 10% PEG stress treatment and the control were significant (P<0.05). According to the predesignedgermination standard, the seeds did not germinate under 20% PEG stress treatment. When the PEG concentration was 15%, the resultsof seed germination potential and germination rate after adding MI were significantly different from those under stress alone (P<0.05).When exposed to 10% PEG stress, the supplementation of GABA led to a notable increase in radicle length of Isatis indigotica seeds,showing significant differences compared to other three treatments. The application of MI and GABA under 15% PEG stress resultedin a significant increase in the radicle and hypocotyl length of Isatis indigotica seeds compared to other two treatments. The contentof the total alkaloids in leaves of Isatis indigotica was significantly increased after spraying GABA. Meanwhile, the contents of crudeprotein and the total free amino acids were kept constant after spraying exogenous substances. Application of MI and GABA couldalleviate drought stress of Isatis indigotica. The content of the total alkaloids in leaves of Isatis indigotica could significantly increaseafter spraying GABA. 展开更多
关键词 Isatis indigotica Fort. exogenous growth regulator drought stress chemical composition leaves of Isatis indigotica
下载PDF
Physicochemical Characterisation of Flours from Local Cereals and Powder from Cassava (Manihot esculenta Crantz) Leaves Varieties Cultivated in the Northern-Cameroon in Order to Supplement Infant Flours
9
作者 Mathieu Barbi Charles Touwang +2 位作者 Emmanuel Panyoo Akdowa Augustin Goudoum Armand Abdou Bouba 《Open Journal of Applied Sciences》 2024年第8期2009-2026,共18页
The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. I... The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. In this paper, a A survey to identify the cereals used in the preparation of infant porridge in the Northern Cameroon was done by using 447 mothers having children between 06 and 59 months from areas (Gbakoungue, Sassa-Mbersi, Sanguere-Ngal and Kotkong-Wouldata) with high rate on malnourished children. Flour was prepared from the most preponderant cereals and Cassava leaves powder from varieties identified by the Regional Centre of Agricultural Research (CRRA) of Wakwa and local population. Flour and powder samples obtained were subjected to chemical composition analysis. Parameters analysed were crude proteins, total carbohydrates, ash, total fats, total phenols, total tannins, total carotenoids, vitamin C or cyanide. Also Iron, calcium and zinc were determined. The results revealed that white maize (62%) was the main cereal used in the preparation of infant porridge followed respectively by red sorghum, white rice and muskwari. Ten cassava varieties were identified: three (03) by CRRA (TME, 96/1/14 and IRAD 4115) and seven (south, gambada, sweet, Benin, six months, M. glaziovii and grouna) by local population. Amongst cereals flour, those from white maize indicated high protein (10.09%), carbohydrates (84.46%) and total fat (7.46%) contents. The powder from 96/14/14 cassava variety showed high amount of iron (11.98 mg/100g), calcium (751.02 g/100g) and low cyanide content (1.21 ppm) amongst all the cassava leaves powder samples. The supplementation of white maize flour by cassava leaves powder from 96/14/14 variety could therefore be recommended for the preparation of infant flours. 展开更多
关键词 Infant Flour Cereals Flour Cassava leaves Powder Chemical Composition Northern Cameroon
下载PDF
The effect of ensiled paulownia leaves in a high-forage diet on ruminal fermentation,methane production,fatty acid composition,and milk production performance of dairy cows 被引量:1
10
作者 Haihao Huang Dorota Lechniak +7 位作者 Malgorzata Szumacher‑Strabel Amlan Kumar Patra Martyna Kozłowska Pawel Kolodziejski Min Gao Sylwester Ślusarczyk Daniel Petrič Adam Cieslak 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期339-357,共19页
Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(... Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(Exp.1;Rusitec)and in vivo(Exp.2,cannulated lactating dairy cows and Exp.3,non-cannulated lactating dairy cows).The study investigated the PLS effect on ruminal fermentation,microbial populations,methane production and concentration,dry matter intake(DMI),and fatty acid(FA)proportions in ruminal fluid and milk.Results:Several variables of the ruminal fluid were changed in response to the inclusion of PLS.In Exp.1,the p H increased linearly and quadratically,whereas ammonia and total volatile fatty acid(VFA)concentrations increased linearly and cubically.A linear,quadratic,and cubical decrease in methane concentration was observed with increasing dose of the PLS.Exp.2 revealed an increase in ruminal p H and ammonia concentrations,but no changes in total VFA concentration.Inclusion of PLS increased ruminal propionate(at 3 h and 6 h after feeding),isovalerate,and valerate concentrations.Addition of PLS also affected several populations of the analyzed microorganisms.The abundances of protozoa and bacteria were increased,whereas the abundance of archaea were decreased by PLS.Methane production decreased by 11%and 14%in PLS-fed cows compared to the control in Exp.2 and 3,respectively.Exp.3 revealed a reduction in the milk protein and lactose yield in the PLS-fed cows,but no effect on DMI and energy corrected milk yield.Also,the PLS diet affected the ruminal biohydrogenation process with an increased proportions of C18:3 cis-9 cis-12 cis-15,conjugated linoleic acid,C18:1 trans-11 FA,polyunsaturated fatty acids(PUFA),and reduced n6/n3 ratio and saturated fatty acids(SFA)proportion in milk.The relative transcript abundances of the 5 of 6 analyzed genes regulating FA metabolism increased.Conclusions:The dietary PLS replacing the alfalfa silage at 60 g/kg diet can reduce the methane emission and improve milk quality with greater proportions of PUFA,including conjugated linoleic acid,and C18:1 trans-11 along with reduction of SFA. 展开更多
关键词 Dairy cow Fatty acid composition in milk Methane emission Paulownia leaves
下载PDF
Antioxidant,antimicrobial,and α-glucosidase inhibitory activities of saponin extracts from walnut(Juglans regia L.) leaves 被引量:1
11
作者 Youssef Elouafy Adil El Yadini +9 位作者 Salma Mortada Mohamed Hnini Hicham Harhar Asaad Khalid Ashraf NAbdalla Abdelhakim Bouyahya Khang Wen Goh Long Chiau Ming My El Abbes Faouzi Mohamed Tabyaoui 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第2期60-69,共10页
Objective:To investigate the relationship between triterpenoid saponin content and antioxidant,antimicrobial,and α-glucosidase inhibitory activities of 70%ethanolic,butanolic,aqueous,supernate and precipitate extract... Objective:To investigate the relationship between triterpenoid saponin content and antioxidant,antimicrobial,and α-glucosidase inhibitory activities of 70%ethanolic,butanolic,aqueous,supernate and precipitate extracts of Juglans regia leaves.Methods:Triterpenoid saponins of different Juglans regia leaf extracts were measured by the vanillin method.Antioxidant activity was evaluated against DPPH and ABTS free radicals.We also assessed α-glucosidase inhibitory and antimicrobial activities of the leaf extracts.Pearson’s correlation coefficient was evaluated to determine the correlation between the saponin content and biological activities.Results:The butanolic extract was most effective against DPPH with an IC50of 6.63μg/mL,while the aqueous extract showed the highest scavenging activity against ABTS free radical with an IC50of 42.27μg/mL.Pearson’s correlation analysis indicated a strong negative correlation (r=-0.956) between DPPH radical scavenging activity (IC50) and the saponin content in the samples examined.In addition,the aqueous extract showed the best α-glucosidase inhibitory activity compared with other extracts.All the extracts had fair antibacterial activity against Bacillus subtilis,Escherichia coli,and Klebsiella pneumoniae except for the aqueous extract.Conclusions:Juglans regia extracts show potent antioxidant,antimicrobial,and α-glucosidase inhibitory activities.There is a correlation between saponin levels in Juglans regia leaf extracts and the studied activities.However,additional research is required to establish these relationships by identifying the specific saponin molecules responsible for these activities and elucidating their mechanisms of action. 展开更多
关键词 Juglans regia leaves Triterpenoid saponin Antioxidant activity DPPH ABTS Antidiabetic activity Α-GLUCOSIDASE Antimicrobial activity
下载PDF
Differences of Physiological and Biochemical Indexes of Upper Fresh Leaves and Post-growth Roots in Different Quality Stages 被引量:1
12
作者 谢碧君 裴晓东 +5 位作者 邓小华 蔡兴 何命军 李帆 黄松青 陈金 《Agricultural Science & Technology》 CAS 2017年第11期2033-2036,2044,共5页
In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde (MDA), superoxide dismutase (SOD) activity, chlorophyllase... In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde (MDA), superoxide dismutase (SOD) activity, chlorophyllase activity, amylase activity, medium trace element content, chemical component content, root fresh weight, dry weight and activity in the normal tobacco leaves, tobacco leaves rich in nutrients and premature grey tobacco leaves were studied. The results showed that compared with the normal tobacco leaves, the root fresh weight, dry weight and activity in the premature grey tobacco leaves decreased by 41.22%, 14.44% and 60.29% respectively, while malonaldehyde content increased by 34.82%, and chlorophyllase, α-amylase, β-amylase and SOD activity declined by 89.55%, 65.71%, 71.26% and 37.25% respectively. Chlorophyllase, co-amylase and 13-amylase activity in the tobacco leaves rich in nutrients decreased by 58.76%, 36.19% and 41.93% respectively. The content of medium trace elements in the tobacco leaves rich in nutrients and premature grey tobacco leaves was lower than that of the normal tobacco leaves. Starch, total sugar, reducing sugar and potassium content in the normal tobacco leaves were higher than that of the tobacco leaves rich in nutrients and premature grey tobacco leaves. 展开更多
关键词 Upper tobacco leaves Root activity Physiological and biochemical properties Medium trace elements Chemical components
下载PDF
Development and validation of an analytical method for detecting chlorantraniliprole residues in fresh tea leaves 被引量:5
13
作者 Tengfei Liu Minghui Dong +2 位作者 Fengjie Zhou Daifeng Yang Xueming Zhang 《Food Science and Human Wellness》 SCIE 2019年第4期362-367,共6页
An efficient method using multiwalled carbon nanotubes(MWCNTs)as dispersive solid-phase extraction sorbent was established for determining chlorantraniliprole residues in fresh tea leaves,which are known to be a troub... An efficient method using multiwalled carbon nanotubes(MWCNTs)as dispersive solid-phase extraction sorbent was established for determining chlorantraniliprole residues in fresh tea leaves,which are known to be a troublesome matrix containing abundant pigments,via gas chromatography with an electron capture detector.Acetonitrile was used as the extraction solvent,with sodium chloride enhancing the analyte partition in the organic phase.The optimal mixture of MWCNTs and primary secondary amine(PSA)was based on the distribution of the target analyte recovery and on the clean-up efficiency;while matrix-matched calibration was recommended to combat the matrix effect.Mean recoveries of 95.2%–108.8%were obtained with intraday and interday precisions of less than 7.9%and 10.3%,respectively.Good linearity was observed for concentrations of 0.02–1.0 mg/kg with a correlation coefficient of 0.9984.The limits of detection and quantification were 0.005 mg/kg and 0.02 mg/kg,respectively.The method was employed to investigate the dissipation dynamics of chlorantraniliprole in fresh tea leaves with real field samples.Consequently,the dissipation rates of chlorantraniliprole in fresh tea leaves followed pseudo-first-order kinetics with a half-life of 1.9 d,and the average chlorantraniliprole residue content was below 0.02 mg/kg with a harvest withholding period of 14 d. 展开更多
关键词 Multiwalled carbon nanotubes fresh tea leaves CHLORANTRANILIPROLE Dispersive solid-phase extraction Gas chromatography
下载PDF
Determination of 18 Kinds of Amino Acids in Fresh Tea Leaves by HPLC Coupled with Pre-column Derivatization 被引量:2
14
作者 Shangwen DONG Tengfei LIU Minghui DONG 《Asian Agricultural Research》 2018年第2期55-58,63,共5页
A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were... A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were minced and mixed,and extracted with ultra pure water at 90℃ for 20 min. The 6-aminoquinolyl N-hydroxy-succinimidyl carbamate( AQC) was used as pre-column derivatization reagent. Gradient HPLC separation was performed on a C_(18) column( Symmetry C_(18),3. 9 mm × 15 cm,4 μm). Good linearity between concentrations and peak areas was achieved in the concentration range of 5. 0-250 μmol/L for 18 kinds of amino acids. The method was validated by the analysis of five replicates. The 18 kinds of amino acid standards were spiked in fresh tea leaf samples and the average recovery rate was 86. 25%-109. 05% with relative standard deviations( n = 5) ranging from 6. 03% to 10. 56%. The limit of detection( LOD) for the analytes was0. 05-1. 27 μmol/L. The method was successfully applied to the analysis of the 18 kinds of amino acids in fresh tea leaves from east Dongting and west Dongting mountains in Suzhou. The results indicate that the method is simple,rapid,precise and reliable. 展开更多
关键词 fresh tea leaves Free amino acids Pre-column derivatization High performance liquid chromatography(HPLC)
下载PDF
Diversity, Chemical Compositions and Beneficial Effects of Some Spices and Aromatic Leaves Consumed in Benin and in the World: Critical Review
15
作者 Carole Vikou Josiane Semassa +6 位作者 Zoriţa Diaconeasa Gautier Roko Majoie Tohoyessou Durand Dah-Nouvlessounon Haziz Sina Andreea Stanilă Lamine Baba-Moussa 《American Journal of Plant Sciences》 CAS 2023年第5期569-598,共30页
Spices and aromatic plants are products of plant origin used in food. They are used for the preparation of remedies, for seasoning dishes or for preserving food. This review takes stock of the diversity of spices and ... Spices and aromatic plants are products of plant origin used in food. They are used for the preparation of remedies, for seasoning dishes or for preserving food. This review takes stock of the diversity of spices and aromatic herbs, the chemical composition, the different properties and forms of use of six spices and aromatic herbs commonly used in Benin and around the world. These are Zingiber officinalis (ginger), Curcuma longa (curcuma), Syzygium aromaticum (clove) and three aromatic herbs Petroselinum crispum (parsley), Rosmarinus officinalis (rosemary), and Laurus nobilis (laurel). The methodology used is that of documentary research oriented towards the consultation of previous scientific documents that have highlighted the different pharmacological activities of the different species of spices and aromatic plants targeted. It is important to note that more than twenty plant species are used as spices and aromatic plants in Benin and around the world. Chemically, these different spices and aromatic herbs contain certain secondary metabolites such as flavonoids, tannins, coumarins, alkaloids, steroids, terpenes, saponins, and polyphenols. This diversity of secondary metabolites alone or in a possible synergy may be responsible for many beneficial properties attributed to spices and aromatic herbs. 展开更多
关键词 SPICES Aromatic leaves Pharmacological Effects Humans
下载PDF
Tomato LysM receptor kinase 4 mediates chitin-elicited fungal resistance in both leaves and fruit
16
作者 Yingfei Ai Qinghong Li +6 位作者 Chenying Li Ran Wang Xun Sun Songyu Chen Xin-Zhong Cai Xingjiang Qi Yan Liang 《Horticulture Research》 SCIE CSCD 2023年第6期170-181,共12页
Fungal infection is a major cause of crop and fruit losses.Recognition of chitin,a component of fungal cell walls,endows plants with enhanced fungal resistance.Here,we found that mutation of tomato LysM receptor kinas... Fungal infection is a major cause of crop and fruit losses.Recognition of chitin,a component of fungal cell walls,endows plants with enhanced fungal resistance.Here,we found that mutation of tomato LysM receptor kinase 4(SlLYK4)and chitin elicitor receptor kinase 1(SlCERK1)impaired chitin-induced immune responses in tomato leaves.Compared with the wild type,sllyk4 and slcerk1 mutant leaves were more susceptible to Botrytis cinerea(gray mold).SlLYK4 extracellular domain showed strong binding affinity to chitin,and the binding of SlLYK4 induced SlLYK4-SlCERK1 association.Remarkably,qRT–PCR analysis indicated that SlLYK4 was highly expressed in tomato fruit,andβ-GLUCURONIDASE(GUS)expression driven by the SlLYK4 promoter was observed in tomato fruit.Furthermore,SlLYK4 overexpression enhanced disease resistance not only in leaves but also in fruit.Our study suggests that chitin-mediated immunity plays a role in fruit,providing a possible way to reduce fungal infection-related fruit losses by enhancing the chitin-induced immune responses. 展开更多
关键词 leaves resistance FUNGAL
下载PDF
Spatiotemporal miRNA and transcriptomic network dynamically regulate the developmental and senescence processes of poplar leaves
17
作者 Kang Du Shenxiu Jiang +6 位作者 Hao Chen Yufei Xia Ruihua Guo Aoyu Ling Ting Liao Wenqi Wu Xiangyang Kang 《Horticulture Research》 SCIE CSCD 2023年第10期162-173,共12页
Poplar is an important afforestation and urban greening species.Poplar leaf development occurs in stages,from young to mature and then from mature to senescent;these are accompanied by various phenotypic and physiolog... Poplar is an important afforestation and urban greening species.Poplar leaf development occurs in stages,from young to mature and then from mature to senescent;these are accompanied by various phenotypic and physiological changes.However,the associated transcriptional regulatory network is relatively unexplored.We first used principal component analysis to classify poplar leaves at different leaf positions into two stages:developmental maturity(the stage of maximum photosynthetic capacity);and the stage when photosynthetic capacity started to decline and gradually changed to senescence.The two stages were then further subdivided into five intervals by gene expression clustering analysis:young leaves,the period of cell genesis and functional differentiation(L1);young leaves,the period of development and initial formation of photosynthetic capacity(L3-L7);the period of maximum photosynthetic capacity of functional leaves(L9-L13);the period of decreasing photosynthetic capacity of functional leaves(L15-L27);and the period of senescent leaves(L29).Using a weighted co-expression gene network analysis of regulatory genes,high-resolution spatiotemporal transcriptional regulatory networks were constructed to reveal the core regulators that regulate leaf development.Spatiotemporal transcriptome data of poplar leaves revealed dynamic changes in genes and miRNAs during leaf development and identified several core regulators of leaf development,such as GRF5 and MYB5.This in-depth analysis of transcriptional regulation during leaf development provides a theoretical basis for exploring the biological basis of the transcriptional regulation of leaf development and the molecular design of breeding for delaying leaf senescence. 展开更多
关键词 NETWORK leaves breeding
下载PDF
Stability Studies on the Aqueous Extract of the Fresh Leaves of Combretum Micranthum G. Don Used as Antibacterial Agent 被引量:1
18
作者 Uduma Eke Osonwa Chukwuebuka Emmanuel Umeyor +2 位作者 Uduak Victor Okon Emmanuel Maduabuchi Uronnachi Calistus Dozie Nwakile 《Journal of Chemistry and Chemical Engineering》 2012年第5期417-424,共8页
The fresh leaves of Combretum micranthum were harvested during the rainy season in Akwa Ibom State, washed and subjected to extraction by maceration in distilled water. Concentration was done with a rotary evaporator.... The fresh leaves of Combretum micranthum were harvested during the rainy season in Akwa Ibom State, washed and subjected to extraction by maceration in distilled water. Concentration was done with a rotary evaporator. The extracts were tested for content of the following phytochemicals using standard methods: alkaloids, saponins, tannins, anthraquinones, cardiac glycosides, flavonoids and steroids. Antibacterial sensitivity test of the extract was carried out on S. aureus, B. subtilis and E. coli using agar well diffusion method and Ampiclox as control. The effect of storage time of the extract on its antibacterial activity was determined after the extract was kept at room temperature for 1 h, 24 h, 48 h and 72 h, respectively. Preparations of 200 mg/mL of the aqueous extract were made with additives as follows: (a) no additive; (b) methyl paraben (0.3%); (c) propyl paraben (0.3%); (d) sodium metabisulfite (0.01%); (e) A combination of methyl paraben (0.3%) and propyl paraben (0.3%); (f) A combination of methyl paraben (0.3%), propyl paraben (0.3%) and sodium metabisulfite (0.01%). A visual observation of the stabilized preparations was employed on daily basis for 30 days. Phytochemical analyses on the aqueous extract of the fresh leaves showed the absence of alkaloids, anthraquinones and flavonoids. Saponins, cardiac glycosides and steroids were present in moderate amounts and there was abundance of tannins. The extract had similar effect on both S. aureus and E. coli cultures but activity was very low with B. subtilis. When S. aureus activity increased with time of storage up to 48 hours, thereafter the activity started reducing. However, the activity of E. coli continued to increase with time (within the study period). Thus, it appears reasonable to store the extract for at least 48 hours before the use for enhanced activity. 展开更多
关键词 Combretum micranthum fresh leaves aqueous extract ANTIBACTERIAL stability.
下载PDF
VG,encoding a thylakoid formation protein,regulates the formation of variegated leaves in tomato
19
作者 Jianwen Song Lijie Guo +4 位作者 Lele Shang Wenqian Wang Chuying Yu Zhibiao Ye Junhong Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第1期98-108,共11页
Leaf-color mutations have been studied extensively in plants.However,to better understand the complex mechanisms underlying the formation of leaf color,it is essential to continue discover novel genes involved in the ... Leaf-color mutations have been studied extensively in plants.However,to better understand the complex mechanisms underlying the formation of leaf color,it is essential to continue discover novel genes involved in the process of leaf color development.In this study,we identified a variegated-leaf(vg)mutant in tomato that exhibited defective phenotypes in thylakoids and photosynthesis.To clone the vg locus,an F2population was constructed from the cross between the vg mutant(Solanum lycopersicum)and the wild tomato LA1589(S.pimpinellifolium).Using the map-based cloning approach,the vg locus was mapped on chromosome 7 and narrowed down to a 128 kb region that contained 21 open reading frames(ORFs).The expression levels of ORF9,ORF10,and ORF13 were significantly lower in vg than in the wild-type plants,while the ORF11 transcript level was elevated in vg.We then mutagenized ORF9,ORF10,and ORF13 by the CRISPR/Cas9 system in the wild-type tomato background and found that only the ORF10 mutation reproduced the phenotype of variegated leaves,indicating that ORF10 represents VG and its down-regulated expression was responsible for the variegated leaf phenotype.ORF10 encodes a thylakoid formation protein and its mutant lines showed reduced levels of chlorophyll synthesis and photosynthesis.Taken together,these results suggest that VG is necessary for chloroplast development,chlorophyll synthesis,and photosynthesis in tomato. 展开更多
关键词 CHLOROPLAST Genetic mapping MUTATION TOMATO Variegated leaves
下载PDF
Phytochemical Profile, Antioxidant, and Anti-Inflammatory Activities, Safety of Use and Spasmolytic Effects of Aqueous Decoction Extract of Diospyros mespiliformis Leaves Hochst. ex A. DC. (Ebenaceae) on the Isolated Duodenum of Rat
20
作者 Mathieu Nitiéma Pegdwendé Esther Ouédraogo +12 位作者 Tata Kadiatou Traoré Oumarou Maman Noura Boukaré Kaboré Wendkouni Leila Marie Esther Bélem-Kabré Windingoudi Rimwagna Christian Ouédraogo Moumouni Koala Bruno Nébié Abdel Magid Arsène Ouoba Makumbu Joseph Makaya Sylvain Ilboudo Lazare Belemnaba Noufou Ouédraogo Sylvin Ouédraogo 《Pharmacology & Pharmacy》 2023年第12期513-529,共17页
Diospyros mespiliformis Hochst. ex A. DC. (Ebenaceae) is a multi-use plant, including for therapeutic purposes. It is used in alternative medicine in Burkina Faso to treat conjunctivitis, menorrhagia, dysentery, and d... Diospyros mespiliformis Hochst. ex A. DC. (Ebenaceae) is a multi-use plant, including for therapeutic purposes. It is used in alternative medicine in Burkina Faso to treat conjunctivitis, menorrhagia, dysentery, and diarrhea. The aim of our study was to evaluate the chemical profile, antioxidant and anti-inflammatory activities, safety of use and spasmolytic effects of the aqueous decoction of Diospyros mespiliformis leaves. Phytochemical screening by HPTLC and assay of compounds of interest were carried out. Four methods were used to assess antioxidant activity. Inhibitory activity against 15-lipoxygenase and phospholipase A2 was assessed. Acute oral toxicity of the extract was tested on female mice (NMRI). Following these tests, the extract contained bioactive compounds of interest such as flavonoids, tannins, sterols, triterpenes, and saponosides. The total phenolic and flavonoid contents of the aqueous decoctate were 70.59 ± 3.20 mg EAT/g and 31.57 ± 0.78 mg EQ/g respectively. The extract was less active than Trolox with inhibitory concentrations of 50% (IC<sub>50</sub>) for the ABTS, DPPH, FRAP, and LPO tests of 7.53 ± 0.08 μg/mL, 29.47 ± 0.06 μg/mL, 1128.83 ± 4.82 mol EAA/g, and 32.30 ± 1.60 μg/mL respectively. The extract has an anti-inflammatory effect with inhibition of phospholipase A2 compared to betamethasone. In addition, the aqueous extract produced an antispasmodic effect with Emax of 70% and 80% respectively during contractions induced by BaCl<sub>2</sub> and ACh. Finally, this study provided basic scientific data and could justify the use of D. mespiliformis leaves in the treatment of diarrhea. 展开更多
关键词 Diospyros mespiliformis PHYTOCONSTITUENTS Antioxidants Acute Oral Toxicity SPASMOLYTIC leaves
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部