Larvicidal activity of endocarp and seed crude extracts of Dracaena loureiri Gagnep against Aedes aegypti(L.) mosquito

Objective: To evaluate the larvicidal activity of the ethanolic and aqueous extracts of the endocarp and seeds of Dracaena loureiri(D. loureiri) against the dengue mosquito vector, Aedes aegypti.Methods: Bioassays were performed by exposing late third-stage to early fourth-stage larvae of Aedes aegypti to various concentrations of the extracts from D. loureiri. The larval mortality was observed after 24-and 48-h exposure.Results: The larvicidal bioassay in this study demonstrated that the ethanolic endocarp extract was the most effective with the LC50 value of 84.00 mg/L after 24 h exposure and< 50 mg/L after 48 h exposure. Extracts from the other parts of the plant were significantly less effective as a larvicide.Conclusions: The ethanolic endocarp extract of D. loureiri demonstrated effective larvicidal activity. It is an alternative source for developing a novel larvicide for controlling this mosquito species.

Chemo-type of essential oil of Ocimum basilicum L.from DR Congo and relative in vitro antioxidant potential to the polarity of crude extracts

Objective:To carry out a phyto-chemical characterization of essential oil from Ocimum basilicum L.(O.basilicum) harvested in DR Congo and to assess the antioxidant potential of crude extracts with respect to the polarity for comparison reason.Methods:The phyto-chemical characterization of essential oil produced by hydrodistillation was performed by coupled gas chromatography-mass spectrometer analysis and the antioxidant potential evaluation by in vitro 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity method.Results:A previously weighed amount of fresh leaves of O.basilicum produced 0.65%of essential oil that led to the identification of a set of 84.44%out of 99.98%as major compounds(> 1.5%).The chemo-type of this essential oil was linalool-methyl chavicol.Chemical components of oil were characterized by oxygenated aromatic hydrocarbons(46.00%) and oxygenated monoterpenes(26.75%).With respect to the amount of components,methyl chavicol also known as estragole(35.72%) constituted the very large quantity afterward linalool(21.25%) and then epi-α-cadinol(8.02%),α-bergamotene(6.56%),eugenol(4.60%),1,8-cineole(4.04%),germacrene D(2.06%),thymol(1.64%),and(E)-citral(1.55%),respectively.Essential oil exhibited antioxidant potential and IC_(50) =(1.180 ± 0.015) mg/mL.Non-polar crude extracts yields were low compared to the one of polar extracts.Only methanol and ethyl acetate had considerably manifested antioxidant potential with IC_(50) values equal to(0.025 ± 0.013) mg/mL and(0.085 ± 0.012) mg/mL,respectively.As concerns to IC50 values,essential oil was less active than methanol and ethyl acetate extracts.The methanol crude extract exhibited the highest activity.Non-polar extracts showed insignificant radical scavenging ability that did not allow assessing IC50 values.These results highlighted the occurrence of antioxidant potential compounds in polar media.Conclusions:Essential oil and crude extracts of O.basilicum growing in DR Congo can be advocated as natural sources of antioxidant potential compounds not only in food but also in pharmaceutical industries.The high antioxidant potential of polar crude extracts highlights antioxidant character of its composition particularly butyl stearate and rosmarinic acid we isolated and identified,respectively in the methanol crude extract.

Antibacterial and Antioxidant Activity of Rhodomyrtus Tomentosa and Cinnamomum Zeylanicum Crude Extracts

The aim of this study was to investigate the extraction method for R.to­mentosa and C.zeylanicum leaves and the evaluation of antibacterial and antioxidant activities of crude extracts.The results of the study showed that the active ingredients of crude extracts were clearly separated by Thin-layer chromatography and the presence of rhodomyrtone in R.tomentosa crude extract and cinnamaldehyde in C.zeylanicum crude ex­tract.R.tomentosa crude extract was antibacterial activity against Staph­ylococcus aureus with 13.1 mm of inhibition zone,but is not effective against Salmonella Typhimurium.C.zeylanicum leaf extract did not show antibacterial activity on both S.aureus and S.Typhimurium.At a dilution of 1/2 of the R.tomentosa crude extract can completely inhibit S.aureus growth.This study also indicated the presence of antioxidant compounds such as flavonoids,tannins,phenols and terpenoids in C.zeylanicum and R.tomentosa crude extracts.The results showed that R.tomentosa and C.zeylanicum crude extracts should be used as a biotherapy alternative to antibiotic therapy.However,further study would be needed to investigate the antibacterial activity of crude extracts in vivo.

Insecticidal Activity of Crude Extracts of Hyptis suaveolens(Bush Mint)on Anopheles Mosquitoes Collected from Lafia,Nasarawa State,Nigeria

Anopheles gambiae is a vector that is responsible for the transmission of malaria parasites which causes high morbidity and mortality in Nigeria and the world at large.Human-vector contact can be reduced by the use of conventional repellents being sold in the market,though some of these repellent are not environmentally friendly and An.gambiae have developed resistance to some of these repellents.To this end,the phytochemical constituents and insecticidal activity of crude extracts of Hyptis suaveolens(bush mint)was determined on adult An.gambiae mosquitoes collected from Lafia,Nasarawa State,Nigeria to evaluate its effect in controlling them.Here,70%ethanolic and diethyl ether fat crude extracts were made from H.suaveolens dried leaves and used to carry out the experiment.The phytochemical screening of the ethanol extract revealed the presence of alkaloids,flavonoid,saponins,tannins,steroids and reducing sugar.Glycoside was not detected in the ethanol extract.Only steroids was detected in diethyl ether extract the rest of the phytochemical tested were absent.An.gambiae larvae were collected from the field and were raised to F1 progeny adults that were used for the study.WHO protocol for carrying out human bait repellency cage test was used.Human hand treated with the extracts was exposed to a cage containing 30 female mosquitoes for each of the extracts respectively.The ethanolic crude extract treatment proved to be more effective in repelling mosquitoes with 0%(0/30)mosquito landing than diethyl ether extract which had 40%(12/30)mosquitoes landing and the control hand(untreated left hand)had the highest landing rate 63.3%(19/30)which showed very high significant difference(χ^(2)=27.2619,df=2,P<0.00001)in relation to the treatments.After 24 hours holding period,the mortality rate of exposed mosquitoes was observed to be highest in the ethanolic treatment 73.3%(22/30).In conclusion,H.suaveolens extracts have repellency potential in controlling adult An.gambiae.

Studies on free-radical scavenging activity and identification of active ingredients of different plant crude extracts of Mentha piperita collected from Sur,Sultanate of Oman

Objective:To determine free radical scavenging activity and active chemical ingredients of different plant crude extracts of Mentha piperita(M.piperita).Methods:The dried powder leaves of M.piperita were extracted with polar organic solvent by Soxhlet extractor.The crude extract and its fractions of hexane,chloroform,ethyl acetate and butanol crude extracts were prepared.The antioxidant activity of different crude extracts from M.piperita was carried out by DPPH method with minor modification,and the active chemical ingredients of different plant crude extracts of M.piperita were analyzed by gas chromatography-mass spectrometry(GC-MS).Results:Qualitative analysis of different polarities crude extracts by GC-MS found different types of active organic compounds.The antioxidant activity of different crude extracts were found to be in the order of chloroform extract>butanol extract>ethyl acetate extract>hexane extract>methanol extract.Majority identified compounds in the plant crude extracts by GC-MS were biologically active.Conclusions:Therefore,the isolation,purification,identification and characterization of bioactive compounds from various crude extracts of M.piperita might have ecological significance.

Phytochemical studies of various polarities leave crude extracts of Omani Datura metel L.and evaluation of their antimicrobial potential

Objective:To identify the chemical constituents and evaluate antimicrobial potential of various crude extracts from leaves of Datura metel grown in Oman.Methods:The leaf samples were collected from the University of Nizwa and extracted with methanol by using Soxhlet extractor.The isolated crude extract was defatted with distilled water and extracted with solvents of different polarities including hexane,chloroform,ethyl acetate and butanol.Chemical compositions of the crude extracts were analyzed by gas chromatography-mass spectrometer and their antimicrobial potential was evaluated by agar disc diffusion method against one Gram positive bacteria Staphylococcus aureus and two Gram negative bacteria Escherichia coli and Pseudomonus aeruginosa.Results:The crude extracts were composed of different organic compounds such as alkaloids,hydrocarbons,aromatic hydrocarbons,organic acids,terpenoids,vitamin etc.The methanol and its fractionated crude extracts showed antimicrobial potential with inhibition zone in the range of 0-13 mm.Conclusions:The selective crude extract from the leaves of Datura metel could be used as natural antibiotics.

Larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri Gagnep against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles minimus mosquito vectors

Objective:To evaluate the larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri endocarp against Aedes aegypti,Aedes albopictus,Culex quinquefasciatus,and Anopheles minimus mosquitos.Methods:Larvicidal activity was tested according to World Health Organization standard protocol.The third-stage larvae of each mosquito species were exposed to various concentrations of Dracaena loureiri crude extract and six groups of Dracaena loureiri fractionated extracts(RC-DT 009-014).Larval mortality rates were observed after 24 h and48 h of exposure.Then,a computerized probit analysis of the mortality data was performed to determine lethal concentration 50(LC_(50))and lethal concentration 90 values.Results:Anopheles minimus larvae(24-h LC_(50)77.88 mg/L)had the highest susceptibility to crude extract,whereas others(Aedes aegypti,24-h LC_(50)224.73 mg/L;Aedes albopictus,24-h LC_(50)261.75 mg/L;and Culex quinquefasciatus,24-h LC_(50)282.86 mg/L)were significantly less susceptible.The most effective groups of fractionated extracts were RC-DT 012 and RC-DT 013.The mosquito species most susceptible to fractionated extracts was Culex quinquefasciatus,with 24-h LC_(50)values of 0.66 and 0.94 mg/L for RC-DT 012 and RC-DT 013,respectively.Conclusions:The larvicidal activity of fractionated extracts is more effective than that of crude extract against all tested mosquito species.For the most effective alternative larvicide,purification and a phytochemical constituent analysis must be performed.

Crude Extract of Detergent⁃Like Gleditsia sinensis lam Exhibiting Self⁃Organization for Protection of Mild Steel in Harsh Hydrochloric Acid Solution:How to Seek Crude Natural Plant Extracts as Green Corrosion Inhibitors

This study proposes a thought to employ detergent⁃like renewable low⁃cost crude extract of Gleditsia sinensis lam(GSL)as green corrosion inhibitor for mild steel in HCl solution.Crude Gleditsia sinensis lam extract(GSLE)was gained at mild conditions by simply refluxing in ethanol with a Soxhlet extractor.The target GSLE extract exhibited regular self⁃organization in mixed solvents of organic solvents/H2O such as ethanol/H2 O(v/v,50/50)at room temperature,which was evidenced by different means including scanning electron microscopy,transmission electron microscopy,and dynamic light scattering.The study demonstrates that the yielded assemblies of the crude extract of GSLE displayed chemical adsorption on the studied mild steel sample surfaces.Furthermore,the formed stable crude extract assemblies of GSL presented outstanding anti⁃corrosion capability in 1.0 mol/L HCl aqueous solution based on electrochemical measurements including polarization curves and impedance spectroscopy.It is discovered that the maximal corrosion inhibition efficiency could reach approximate 95%.The molecular modeling was performed to acquire the nature of frontier orbitals of the main representative chemical components of crude GSLE for deep understanding of chemical interactions with iron.The results presented herein would guide us to seek sustainable environmentally friendly low⁃cost detergent⁃like plant crude extracts for corrosion inhibition of various metals in aggressive acid environments.

Effect of Soy Isoflavone Crude Extract Supplementation on High Fat Diet-induced Insulin Resistance in Ovariectomized Rats

Female Wister rats aged 8 weeks were randomly divided into sham operation group, ovariectomized （OVX） control group, and 20VX groups fed with soy isoflavone crude extract supplementation. The rats had free access to high fat diet and water for 9 weeks. No significant difference was found in body weight （BW）, total abdominal fat, food intake and food utilization rate between OVX control group and 20VX groups. However, the fasting blood glucose and blood lipid levels were significantly higher in 20VX groups than in OVX control group （P〈0.05）. Intraperitoneal glucose tolerance test （IGTI＂） showed that the area under AUC was smaller in 20VX groups than in OVX control group （P〈0.05）. These findings showed that soy isoflavone crude extract supplementation can improve glucose tolerance and prevent high fat diet-induced insulin resistance in ovariectomized rats.

A Study on the Pyrolytic Characteristics of Xanthoceras Sorbifolia Husk and Its Crude Cellulose Extract

Huge amounts of Xanthoceras sorbifolia husks(XSH)are typically discarded after oil extraction.Since pyrolysis represents a promising solution to harness the bio-energy of XSH,in the present work the pyrolytic and kinetic characteristics of XSH and related crude cellulose extract(CCE)were studied considering different rates of heating(10,30 and 50℃ min^(-1)).The pyrolysis activation energy,pre-exponential factors and mechanism function were computed using different models namely Popescu,FWO(Flynn-Wall-Ozawa)and KAS(Kissinger-Akahira-Sunose).The pyrolysis process was articulated into three stages:dehydration(Stage I),primary devolatilization(Stage II),residual decomposition(Stage III).Marked variations in the average activation energy,thermal stability,final residuals and rate of reaction were noted.Stage II of XSH and CCE could be described by the Avramic-Erofeev equations.The average activation energies of XSH and CCE were found to be 269 and 296 kJ mol^(-1),respectively.

Identification of phytochemical compounds in Calophyllum inophyllum leaves

Objectives: To investigate the proximate composition, mineral content, and phytochemical compounds in Calophyllum inophyllum(C. inophyllum) leaves. Moreover,isolation and identification of pyrene were also performed.Methods: C. inophyllum leaves were extracted with methanol by percolation methods.The proximate composition of C. inophyllum leaves was analyzed by standard methods.Mineral contents in this plant were analyzed by using atomic absorption spectrophotometer. Phytochemical screening and analysis of this plant were performed by spectrophotometric method. Washing method with carbon disulfide was used for isolating dihydropyrene compound from C. inophyllum leaves extracts.Results: The result revealed that C. inophyllum leaves contained 11.24% moisture,4.75% ash, 6.43% crude protein, 23.96% crude fiber, 9.91% carbohydrate, and energy(79.17 kcal/100 g). The leaves also contained 0.007% iron, 1.240% calcium, 0.075%sodium, 0.195% magnesium, 0.100% ppm potassium, and 0.040% phosphorus. Moreover, 11.51% alkaloid, 2.48% triterpenoid, 2.37% flavonoid, 7.68% tannin, 2.16%saponin, 2.53% polyphenol, were identified in the methanolic crude extracts of C. inophyllum leaves. It was found that trans-2-[2-(trifluoromethyl)phenyl]-10 b,10 c-dimethyl-10 b,10 c-dihydropyrene was obtained at purity of 79.18%(22.17% yield)from C. inophyllum leaves.Conclusions: C. inophyllum leaves may be used as a good source of fiber. It was found that C. inophyllum leaves have the potential as herbal drugs due to their phytochemical content. The separation, isolation, and purification of bioactive compounds from this methanolic crude extract and their biological activity are under further investigation.

Screening and Characterization of Antibiotic Producing Organisms from Waste Dump Soil Sample

This study was designed to screen and characterize antibiotic producing bacteria and fungi from soil samples from a waste dump site in Enugu. The molecular characterization of the isolates was performed by using Zymo Research Quick-DNA fungi/bacteria miniprep kit. The bacteria isolates were Providencia stuartii, Providencia alcalifaciens. Bacillus sp., Streptococcus sp., Micrococcus sp., and Staphylococcus sp while Aspergillus fumigatus and Aspergillus niger were fungal isolates. The efficacy of the Crude Extract (CE) of the antibiotics produced was tested against species of Staphylococcus aureus and Escherichia coli. The CE of antibiotics when compared with a conventional antibiotic (Ciprofloxacin) showed lower antimicrobial activity. The minimum inhibitory concentration of the crude extracts ranged between 12.5% and 25% concentrations while the minimum bactericidal concentration ranged from 25% and 50% concentrations. The findings suggest that these organisms have the potential to produce antibiotics and could be harnessed by pharmaceutical industries for the production of newer antibiotics.

Anticancer Effects of Crude Extract from Melia toosendan Sieb.et Zucc on Hepatocellular Carcinoma In Vitro and In Vivo

Objective： To investigate the anti-cancer effects of crude extract from Melia toosendan Sieb. et Zucc and its possible molecular mechanisms in vitro and in vivo. Methods： Transonic alcohol-chloroform extraction method was used to extract toosendanin from the bark of Melia toosendan Sieb. et Zucc, and the content of toosendanin in the crude extract was measured by high performance liquid chromatography （HPLC）. Anti-cancer effects of crude extract from Melia toosendan Sieb. et Zucc were investigated in in vivo and in vitro studies. In the in vitro experiment, human hepatocellular carcinoma cell lines SMMC-7721 and Hep3B were co-incubated with toosendanin crude extract of different concentrations, respectively. In the in vivo experiment, BALB/c mice were subcutaneously inoculated with mouse hepatocellular carcinoma H22 cells and treated with crude extract. Results： HPLC revealed the content of toosendanin was about 15%. Crude extract from Melia toosendan Sieb. et Zucc inhibited cancer cells growth in a dose- and time-dependent manner. The 50% inhibitory concentration （IC50, 72 h） was 0.6 mg/L for SMMC-7721 cells and 0.8 mg/L for Hep3B cells. Both high-dose [0.69 mg/（kg·d）] and low-dose [0.138 mg/（kg·d）] crude extract could markedly suppress cancer growth, and the inhibition rate was greater than 50%. Hematoxylin and eosin staining showed necrotic area in cancers and transmission electron microscopy displayed necrotic and apoptotic cancer cells with apoptotic bodies. Immunohistochemistry showed that the expression of Bax and Fas increased and the expression of Bcl-2 reduced. Conclusions： Toosendanin extract has potent anti-cancer effects via suppressing proliferation and inducing apoptosis of cancer cells in vivo and in vitro. The mechanism of apoptosis involves in mitochondrial pathway and death receptor pathway.

Acaricidal activities of whole cell suspension,cell-free supernatant,and crude cell extract of Xenorhabdus stokiae against mushroom mite (Luciaphorus sp.)

Xenorhabdus bacterium has been used as a biological control agent against Luciaphorus sp.,a mushroom mite endemic in Thailand.To develop an effective formulation of Xenorhabdus stokiae,treatments using different parts of X.stokiae isolate PB09 culture,including whole cell suspension,cell-free supernatant,and crude cell extract,were performed.The results show that different parts of X.stokiae isolate PB09 culture could induce variable effects on mite mortality and fecundity.Application with cell-free supernatant of X.stokiae culture resulted in both the highest mite mortality rate [(89.00±3.60)%] and the lowest mite fecundity [(41.33±23.69) eggs/gravid female].Whole cell suspen-sion of X.stokiae isolate PB09 culture was found to be slightly less effective than its cell-free supernatant,suggesting that X.stokiae was more likely to release its metabolites with acaricidal activities to the surrounding culture media.Crude cell extract of X.stokiae was not effective against mites.Cell-free supernatant of X.stokiae isolate PB09 was the most effective biological control agent and it could be conveniently used in future formulations instead of live bacteria.

Antioxidant and antitumor effects and immunomodulatory activities of crude and purified polyphenol extract from blueberries

The antioxidant and antitumor effects as well as the immunomodulatory activities of crude and purified polyphenol extract from blueberries were investigated. The antioxidant and antitumor effects of the polyphenol extract were measured both in vitro and in vivo, and their effect on the immune systems of CD-1 tumor-bearing mice were also analyzed. In vitro assays demonstrated that blueberry purified polyphenol extract （BBPP） exhibited higher antioxidant activities than blueberry crude polyphenol extract （BBCP）, but the opposite effect was observed in vivo. Both the in vitro and in vivo antitumor activity and the immunity assay showed that BBCP not only inhibited tumor growth, but also significantly improved the immunity of the mice. According to physical and histological studies, the CD-1 tumor-bearing mice treated with the polyphenol extract, especially high doses of BBCP experienced a higher quality of life than the positive control group （treated with cyclophosphamide）. These results indicate that BBCP has significant antioxidant and antitumor activities and that it can enhance the immunity of CD-1 tumor-bearing mice.

Antibacterial potential of some plants of traditional use in India against pathogenic strains of S.aureus

Objective:To evaluate antibacterial sensitivity of 43 ethnomedicinally important plants belonging to 25 different families from Western Uttar Pradesh,a northern province in India,against hospital isolated pathogenic strains of Staphylococcus aureus(S.aureus).Methods:Methanol(MeOH)and aqueous extracts of plants were subjected to sensitivity test against S.aureus ATCC 25953 and two hospital isolated virulent strains of S.aureus SA1 and SA2 following disc diffusion assay to determine sensitivity and agar dilution method to test minimum inhibition concentration using Mueller-Hinton agar.Results:Potential antibacterial activity was recorded for MeOH extracts against test pathogens,while moderate antibacterial activity was observed in case of aqueous extracts.Out of 43 plant species,39 species were found sensitive to tested strains.Minimum inhibition concentration values of MeOH extracts were demonstrated at low concentration ranging from 15.5 mg/mL up to 45.5 mg/mL compared to aqueous extracts which were observed ranging from 30.0 mg/mL up to 95.0 mg/mL.Conclusions:The present findings strongly support traditional uses of these plants in the treatment of infectious maladies and further urge of phytochemical and pharmacological research to develop safer and cheaper drugs for the benefit of ailing humanity.

Bioactive compounds and antifungal activity of three different seaweed species Ulva lactuca,Sargassum tenerrimum and Laurencia obtusa collected from Okha coast,Western India

Objective:To evaluate bioactive compounds responsible for antifungal activity from seaweeds of Okha coast,Western India.Methods:Each species were extracted with different solvents with increasing polarity:hexane,ethyl acetate,chloroform and methanol using Soxhlet apparatus.The antifungal activity was determined by agar diffusion plate method by using fluconazole,ketoconazole and amphotericin B as standards.Gas chromatography-mass spectrometer analysis was done for identification of bioactive compounds present in crude extract.Results:The gas chromatography-mass spectrometer analysis of all the extracts revealed the presence of steroids,fatty acids and esters compounds.Among the three species,the maximum crude extract yield(53.46%)and the largest inhibition zone(36 mm)were recorded in methanol extract of Ulva lactuca,whereas the minimum crude extract yield and inhibition zone were recorded in chloroform extract of the same species as 0.5%and 10 mm,respectively.Methanol and ethyl acetate extract showed the maximum antifungal activity and the major important compounds like steroids,fatty acids and esters were detected with higher amount in all the extracts.Conclusions:The present study revealed that the different seaweed extracts showed moderate to significant antifungal activity against the strains tested as compared with the standard fungicides,and polar solvents methanol and ethyl acetate were comparatively efficient for extraction of different metabolites that are responsible for antifungal activity.

An in vitro efficacy validation of mangrove associates

Objective:To investigate the in vitro antimicrobial potential of mangrove associates against a battery of human and shrimp pathogenic bacteria and to elucidate its antimicrobial principles.Methods:In the present study,12 species of mangrove associates collected from the Kollam(southwest coast of India)vicinity were extracted in different organic solvents of increasing polarity.The resultant extracts obtained from the respective species were examined for the antimicrobial activity against a panel of shrimp and human pathogens by agar diffusion assay.Results:Of the 12 species evaluated,three species of mangrove associates[Calophyllum inophyllum(C.inophyllum),Cerbera odollam and Dalbergia candenatensis]were found to be active.The broadest and highest rank of activity was observed in the crude extract of C.inophyllum.Amongst the pathogens tested,shrimp pathogenic Vibrios were the most sensitive organisms while human pathogens were found to be a bit resistant.In the present study,ethyl acetate was found to be the best solvent for extracting antimicrobial metabolites.The bioactive principles present in the crude extract of C.inophyllum were chemically elucidated by gas chromatography-mass spectrometer.The gas chromatography-mass spectrometer studies revealed the presence of two principal compounds such as 1-Dimethyl(phenyl)silyloxyhexadecane(24.73%)and β-d-Mannofuranoside,O-geranyl(50%)which might play functional role in the chemical defense against microbial invasion.Conclusions:Based on the overall findings,it could be inferred that the mangrove associate C.inophyllum is a promising candidate for the development of plant-based human and veterinary grade antibiotics in future.

Analysis of in vitro antioxidant activity of Caryota urens L.leaves:A traditional natural remedy

Objective:To estimate the antioxidant potentiality of crude ethanol extract(CEE),chloroform fraction(CLF),ethyl acetate fraction(EAF)and methanol fraction(MNF)of Caryota urens L.(C.urens)leaves.Methods:Antioxidant activity of C.urens leaves was determined by total antioxidant activity,2,2-diphenyl-2-picrylhydrazyl radical scavenging assay and hydroxyl radical scavenging assay.Total phenolic content and total flavonoid content were determined for phytochemical constituent’s characterization.Results:The CEE of the C.urens leaves showed the highest total antioxidant activity compared to CLF,EAF and MNF.In the 2,2-diphenyl-2-picrylhydrazyl scavenging assay and the hydroxyl radicalscavenging assay,CEE showed the highest scavenging activity(42.36%and 53.36%)having IC50 of 472.14 and 374.81μg/mL respectively with respect to other fractions.The ranking order of CEE,MNF,EAF and CLF for total phenolic content was 155.74>106.8>83.95>71.49 mg gallic acid equivalent/g of dried extract,respectively.Total flavonoid content was found to be the highest in the CEE(101.35 mg of quercetin equivalent/g of dried extract)rather than other fractions.Conclusions:This study recommended that CEE of C.urens leaves can be considered as a potential source of natural antioxidant and can be used against diseases linked with free radical mediated oxidative stress.