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Asian Pacific Journal of Tropical Biomedicine 2014年第12期4卷 964-970页

作者： Mooza Al-Owaisi Nora Al-Hadiwi Shah Alam Khan Department of Pharmacy Oman Medical College

Objective:To perform phytochemical screening,estimate total phenolics,flavonoids and to evaluate antioxidant potential of Moringa peregrina(***) ***:The dried powdered leaves of ***(150 g) were extracted exhaustively by Soxhlet with ethanol and then fractionated into hexane,chloroform,ethy alacetate and *** the prepared extracts were also analyzed by gas chromatography-mass spectrometry to identify and characterize the chemical compounds present in the crude ***- Ciocalteu reagent and aluminium chloride colorimetric methods were used to estimate total phenolic and flavonoid content of *** peroxide and 1,1 diphenyl-2-picrylhydrazyl were used to determine in vitro antioxidant ***:Phytochemical analysis of ethanol extract showed presence of major classes of *** chromatography-mass spectrometry results revealed presence of 19 phytoconstituents in hexane extract,6 in ethyl acetate and 7 compounds in methanolic *** extract was found to contain the highest phenolic content and *** vitro antioxidant activities of all crude extracts were significant and comparable with the standard ascorbic ***:Results of this study show that the leaves of *** are the rich source of phenolic compounds that can play an important role in preventing the progression of many diseases.

关键词： Antioxidant activity Flavonoid content gc-ms analysis Moringa peregrina Total phenolics

CS_2 extraction and FTIR & gc/ms analysis of a Chinese brown coal

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Mining Science and Technology 2010年第4期20卷 562-565页

作者： TIAN Damin LIU Xiangyun DING Mingjie Department of Chemistry and Chemical Engineering Henan University of Urban Construction Pingdingshan 467044 China School of Chemical Engineering China University of Mining & Technology Xuzhou 221008 China

The abundance of low-rank coals in China, such as bituminous and brown coals, makes studies of their composition and structure of great significance to both coal chemistry research and for efficient utilization of the coal. We describe how a Chinese brown coal was ultrasonically extracted with carbon disulfide （CS2） and the raw and extracted coals were characterized by Fourier Transform Infrared Spectroscopy （FTIR）. The corresponding extract was analyzed with a coupled gas chromatograph mass spectrometer （gc/ms）. The FTIR analysis shows a great abundance of amidocyanogen, carbonyl, aromatic and hetero aromatic rings and single carbon-beteroatom bonds. This suggests the possible occurrence of compounds like alcohols, phenols, amines, esters, carboxylic acids, ethers, aromatics or heteroaromatics. The gc/ms analysis of the CS2 extract detected 62 compounds, among which the non-polar ones were of lower abundance while the polar ones were in higher abundance and were structurally diverse. This demonstrates the compositional and structural complexity of Shengli coal.

关键词： low-rank coal solvent extraction FTIR gc-ms analysis

Phytochemical analysis and Antimicrobial Activity of Lawsonia inermis Leaf Extracts from Burkina Faso

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American Journal of Plant Sciences 2024年第7期15卷 552-576页

作者： Ollo Youl Soumaïla Konaté Ernest N. Sombié Rainatou Boly Boukaré Kaboré Moumouni Koala Arouna Zoungrana Saybou Savadogo Christian Marc Tahita Innocent Valea Halidou Tinto Adama Hilou Maminata Traoré-Coulibaly Laboratoire de Biochimie et de Chimie Applique (LABIOCA) Universit de Ouagadougou Ouagadougou Burkina Faso Agence Nationale Pour la Scurit Sanitaire de lEnvironnement de lAlimentation du Travail et des Produits de Sant (ANSSEAT) Ouagadougou Burkina Faso Laboratoire de Recherche-Dveloppement de Phytomdicaments et Mdicaments (L-RD/PM) Institut de Recherche en Sciences de la Sant (IRSS-CNRST) Ouagadougou Burkina Faso Laboratoire de Chimie Organique et de Physique Applique (LCOPA) cole Doctorale Sciences et Technologie Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire Sciences de la Vie et de la Terre (LASVT) cole Doctorale Sciences et Technologie Universit Norbert ZONGO Koudougou Burkina Faso Unit de Recherche Clinique de Nanoro Institut de Recherche en Sciences de la Sant (IRSS-CNRST) Nanoro Burkina Faso

Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (gc-ms), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. gc-ms detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested s

关键词： Lawsonia inermis Phytochemical Profile HPLC gc-ms analysis Antimicrobial Activity

Zeolite-assisted etherification of glycerol with butanol for biodiesel oxygenated additives production

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Journal of Energy Chemistry 2020年第9期29卷 136-144,I0005页

作者： C.Cannilla G.Bonura S.Maisano L.Frusteri M.Migliori G.Giordano S.Todaro F.Frusteri CNR-ITAE Istituto di Tecnologie Avanzate per l'Energia“Nicola Giordano”Via S.Lucia 598126 MessinaItaly Dipartimento di Ingegneria Elettronica Chimica e Ingegneria IndustrialeUniversitàdi MessinaContrada di Dio I98166 MessinaItaly Bucci 97036 RendeItaly

This research was focused on the valorisation of glycerol,exploring the feasibility of an efficient route for oxygenated additives production based on its etherification with bio-butanol.A home-made BEA zeolite sample with a tuneable acidity has been proposed as the catalytic system,being tested in a stirred reactor under different etherification *** a reaction temperature as high as 200℃resulted to be beneficial in terms of glycerol conversion(-90%),only by operating at milder conditions the product selectivity to glycerol-ethers can be better controlled,in order to obtain a bio-fuel complying with the requirements for mixing with fossil diesel or biodiesel,without any need of purification from large amount of by-products.A comprehensive identification of all the compounds formed during the reaction was performed by a gc-ms analysis,on the basis of the complex network of consecutive and parallel reaction paths leading not only to the desired ethers,but also to many side products not detected in similar acid-catalyzed reactions in liquid phase and not available in the most used mass-spectra libraries.

关键词： Glycerol Butanol BEA gc-ms analysis Acid catalysts Biofuels Butyl glycerol ethers

Evaluation of the gastrointestinal anti-motility effect of Anacardium occidentale stem bark extract:A mechanistic study of antidiarrheal activity

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Journal of Pharmaceutical analysis 2021年第6期11卷 776-782页

作者： Blessing O.Omolaso Francis S.Oluwole Olugbenga A.Odukanmi Julius K.Adesanwo Ahmed A.Ishola Kayode E.Adewole Department of Physiology Faculty of Basic Medical SciencesUniversity of Medical SciencesOndo City340001Ondo StateNigeria Department of Physiology College of MedicineUniversity of IbadanIbadan200001Nigeria Department of Chemistry Obafemi Awolowo UniversityIle-Ife230001Osun StateNigeria Central Research Laboratories Limited University Road IlorinKwara State240001Nigeria Department of Biochemistry Faculty of Basic Medical SciencesUniversity of Medical Sciences340001Ondo StateNigeria

Diarrhea is a prevalent gastrointestinal problem associated with fatal *** is a huge public health concern that requires better alternatives to current *** study investigated the mechanisms involved in the antidiarrheal activity of Anacardium occidentale(Ao) stem bark extract,a plant commonly used in the management of diarrhea in *** stem bark extract of the plant was partitioned into three fractions:hexane fraction,ethyl acetate fraction(Ao EF) and methanol *** vitro studies on the effect of these fractions on guinea pig ileum(GPI) strips,as well as the modulatory effect of Ao EF on standard agonists-and antagonists-induced GPI contraction and relaxation,revealed Ao EF as the most active *** vivo studies to assess the effect of Ao EF on the dopaminergic,muscarinic,and serotonergic pathways were carried out using gastric emptying(GE) and gastrointestinal transit(GT) as experimental end *** EF was subjected to gc-ms analysis,while the identified compounds were docked with the muscarinic acetylcholine receptor M3(CHRM3) using Autodock *** indicated that Ao EF inhibited GE and GT via inhibition of *** addition,gc-ms analysis revealed the presence of 24 compounds in Ao EF,while docking indicated that octadecanoic acid 2-(2-hydroxylethoxy)ethyl ester exhibited the highest binding affinity to *** study indicated that the antidiarrheal activity of Ao is through its antimotility effect via the inhibition of the muscarinic *** since none of the identified compounds exhibited higher binding affinity to CHRM3 relative to loperamide,the antimotility activity of these phytoconstituents may be via synergism.

关键词： Anacardium occidentale Antidiarrheal Muscarinic receptor Gastric emptying Gut motility gc-ms analysis

Exploitation of the antibacterial,antibiofilm and antioxidant activities of Salvadora Persica(Miswak)extract

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Journal of Bioresources and Bioproducts 2023年第1期8卷 59-65页

作者： Gamal M.El-Sherbiny Ahmed Mohamed Gazelly Mohammed H.Sharaf Saad A.Moghannemm Shehata M.E Mahmoud K.A.Ismail Ahmad S.El-Hawary Botany and Microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt

The Salvadora persica(***)*** stick,usually known as miswak,is still being em-ployed as an oral hygiene agent for plaque and gingivitis *** study aims to assess the antibacterial,antibiofilm,antioxidant,and phytochemical profile of *** *** ***-sica was purchased from a local market,grinded and extracted with petroleum *** disk dif-fusion,microdilution,and micro-plate assays were performed to evaluate the antibacterial and an-tibiofilm activities of the prepared extract at different concentrations against𝛽-lactam resistance Streptococcus *** radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)and stable radical cationic chromophore,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate)(ABTS)methods were used to determine their antioxidant *** and spectrometric analyses were performed using gas chromatography-mass(gc-ms)*** minimum inhibitory concentration(MIC)of *** extract against𝛽-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/*** maximum suppression of biofilm formation by *** extract was observed at MIC with a percentage of 68.66%,against Streptococcus *** *** ex-tract exhibited antioxidant activity with IC 50 of 20μg/mL and 35μg/mL from DPPH and ABTS,*** phytochemical characterization showed the presence of 22 compounds with ma-jor compounds;benzyl isothiocyanate(36.21%)and n-hexadecanoic acid(27.62%).The *** extract exhibited antibacterial activity against𝛽-lactam resistant Streptococcus species,showing a promising natural alternative that could be a treatment option.

关键词： β-lactam resistance Streptococcus species S.persica extract Antibacterial Antibiofilm Antioxidant gc-ms analysis

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

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Asian Pacific Journal of Tropical Biomedicine 2016年第12期6卷 1022-1028页

作者： Dorothee Dinangayi Tshilanda Philippe Bila Babady Damase Nguwo Vele Onyamboko Christian Muamba Tshilolo Tshiongo Damien Sha-Tshibey Tshibangu Koto-te-Nyiwa Ngbolua Philippe Vuka Tsalu Pius Tshimankinda Mpiana Department of Chemistry Faculty of ScienceUniversity of Kinshasa Bila Nutraceuticals Company Department of Biology Faculty of ScienceUniversity of Kinshasa

Objective:To carry out a phyto-chemical characterization of essential oil from Ocimum basilicum L.(***) harvested in DR Congo and to assess the antioxidant potential of crude extracts with respect to the polarity for comparison ***: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 ***:A previously weighed amount of fresh leaves of *** 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 *** 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%),*** oil exhibited antioxidant potential and IC_(50) =(1.180 ± 0.015) mg/***-polar crude extracts yields were low compared to the one of polar *** 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,*** concerns to IC50 values,essential oil was less active than methanol and ethyl acetate *** methanol crude extract exhibited the highest ***-polar extracts showed insignificant radical scavenging ability that did not allow assessing IC50 *** results highlighted the occurrence of antioxidant potential compounds in polar ***:Essential oil and crude extracts of *** growing in DR Congo can be advocated as nat

关键词： Ocimum basilicum L. Essential oil Polar and non-polar crude extracts In vitro antioxidant potential gc-ms analysis

Chemical compositions,cytotoxicity and antioxidant activity of the endophytic fungus Fusarium napiforme isolated from Psidium guajava

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Studies in Fungi 2020年第1期5卷 332-352页

作者： Chutulo EC Chalannavar RK Pramod Kumar P Department of Studies&Research in Microbiology Mangalore UniversityJnana KaveriP.G.CentreChikka AluvaraKodagu-571232KarnatakaIndia Department of Biosciences Mangalore UniversityMangalagangotri-574199KarnatakaIndia Department of Biology Wolaita Sodo UniversityWolaita SodoEthiopia Department of Applied Botany Mangalore UniversityMangalagangotri-574199KarnatakaIndia Department of Biochemistry CSIR-Central Food Technological Research InstituteMysuru-570020KarnatakaIndia

The bioactive secondary metabolites from the endophytic fungus Fusarium napiforme was evaluated for the cytotoxic effect and antioxidant *** total antioxidant capacity(TAC)of the extract was determined by 2,2-diphenyl-1-picrylhydrazyl(DPPH),phosphomolybdate,and reducing power assay *** cytotoxicity of the extract was evaluated against lung adenocarcinoma(A549)cells and mouse embryo fibroblast(NIH3T3)cells by methyl thiazolyl tetrazolium(MTT)*** major composition of the crude extract was identified by the Gas Chromatography-Mass Spectrometry(gc-ms)*** of the endophyte crude extract revealed a high amount of the total flavonoid content(TFC)and total phenolic content(TPC).The extract showed high cytotoxic activity against the A549 cell line with the mean cytotoxicity of 69.74±0.49%.The extract did not show any cytotoxic effect against the NIH3T3 cell *** extract exhibited high antioxidant activity as a function of the *** a test concentration of 1 mg ml-1,the extract showed the highest inhibition against DPPH radical at 75.4607%±0.47688,ferric ion reducing power at 0.882±0.0120,and 255.434±21.404 AAE/g of the extract by phosphomolybdenum assay(PMA).There is a significant correlation between TPC and antioxidant activity at pgc-ms have shown the presence of nine major *** result strongly exhibits that the endophyte *** can be a potential source for the formulation of natural anticancer drugs and protecting the body from oxidative damages.

关键词： flavonoids gc-ms analysis lung adenocarcinoma cells mouse embryo fibroblast cells MTT assay phenolics

Experimental study of the influence of acid wash on cellulose pyrolysis

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Frontiers of Chemical Science and Engineering 2007年第1期1卷 35-39页

作者： WANG Shurong LIAO Yanfen LIU Qian LUO Zhongyang CEN Kefa State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China Electric Power College South China University of TechnologyGuangzhou 510640China

The analysis of microstructure and polymeriza-tion degree showed that acid wash altered the cellulose morphology and decreased the polymerization degree signifi-cantly.A series of experiments were done to study the effect of acid wash on cellulose rapid *** results showed that under acid pretreatment,the yield of bio-oil decreased while the production of gas and char *** an increase in acid concentration,this trend would be further *** acid limited the formation of bio-oil more effectively than hydrochloric acid and pho-sphoric *** to the gc-ms analysis of bio-oil,high-concentration acid wash restrained the formation of levoglucosan by catalyzing dehydration process and cross linking reaction.

关键词： cellulose acid wash pyrolysis bio-oil gc-ms analysis

Chemical Composition and in Vitro Antibacterial Activity of the Leaf Essential Oil of Mentha officinalis from Rwanda

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Journal of Chemistry and Chemical Engineering 2012年第5期6卷 401-409页

作者： Kabera Justin Muhayimana Protaist Nyirahashakimana Rose Ugirinshuti Vlateur Essential oils Unit Institute of Scientific and Technological Research （IRST） Butare 227 Rwanda Department of Chemistry Faculty of Sciences National University of Rwanda Butare 116 Rwanda Department of Education in Chemistry Faculty of Education National University of Rwanda Butare 116 Rwanda Biotechnology Unit Institute of Scientific and Technological Research （IRST） Butare 227 Rwanda

The search for new prototype drugs to combat infection is an absolute necessity and in this regard plant essential oils may offer great potential and hope. In this investigation, the essential oil of the leaves ofMentha officinalis grown in Rwanda was extracted by hydrodistillation method and analyzed by gas chromatography （gc） and gas chromatography coupled with mass spectrometry （gc-ms）. The disc diffusion method was used to evaluate in vitro the zone of bacterial growth inhibition at various concentrations of the oil for five bacterial strains： Escherichia coli, Bacillus aureus, Streptococcus lactis, Staphylococcus aureus and Salmonella typhimurium. The results of this study revealed many components among which the major components were menthol （80.79%）, menthone （4.906%）, isomenthone （3.5%）, piperitone （2.56%）, and methyl acetate （2.2%）. After 7 days of incubation on PCA medium, the growth of Escherichia coli, Bacillus aureus, Streptococcus lactis and Staphylococcus aureus was totally inhibited at an average diameter of 19 mm, 32 mm, 50 mm and 30 mm respectively by a medium concentration of 30 μm/disc ofM. officinalis oil. Quite the reverse, this investigation by a bioassay showed that the essential oil ofM. officinalis has no effect on Salmonella typhimurium. The obtained results in the present study indicate the possibility of exploiting the essential oil ofM. officinalis to combat so many infectious human diseases in Rwanda. However, further investigations are required to make the medical exploitation of this plant successful.

关键词： Antibacterial activity chemical composition essential oil gc-ms analysis Mentha officinalis.