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antibacterial activity and Toxicity of the Sap and Aqueous Extract of the Leaves of Jatropha multifida Linn

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Journal of Biosciences and Medicines 2022年第7期10卷 171-182页

作者： Maximin Senou Jacques Ezéchiel Lokonon Edjégué Oloroun-Togni Ruth Abissi Félicienne Agbogba René J. Dehou Espérance Medoatinsa Pascal Tchogou Boris Fresel Cachon Alban Houngbeme Eugène Attakpa Amègnona Agbonon Lamine Baba-Moussa Laboratory of Experimental and Clinical Biology National School of Applied Biosciences and Biotechnologies National University of Sciences Technologies Engineering and Mathematics (UNSTIM) Abomey The Republic of Benin Laboratoire de Biologie Appliquée (LARBA) Ecole Polytechnique d’Abomey-Calavi (EPAC) Université d’Abomey-Calavi (UAC) Godomey The Republic of Benin Laboratoire National de Pharmacognosie/Centre Béninois de la Recherche Scientifique et Technique (CBRST) Cotonou The Republic of Benin Laboratoire de Physiopathologie Moléculaire et Toxicologie de la Faculté des Sciences et Techniques (FAST) de l’Université d’Abomey-Calavi (UAC) Godomey The Republic of Benin Laboratoire de Physiologie/Pharmacologie Faculté des Sciences Université de Lomé Lome The Republic of Togo Laboratory of Biology and Molecular Typing in Microbiology University of Abomey-Calavi Cotonou The Republic of Benin

Introduction: Jatropha multifida Lin was a plant of traditional Beninese medicine used as an antibiotic. This study aimed to evaluate the antibacterial activity and the toxicity of the sap and the aqueous extract of Jatropha multifida leaves. Methods: Phytochemical screening of Jatropha multifida leaves was carried out. The extract was obtained by maceration. The antimicrobial activity of sap and leaves was evaluated on the five strains of hospital germs. Acute oral toxicity by forced gavage in a single dose of 2000 mg/kg body weight was performed on female Wistar rats. Biochemical and hematological parameters were determined. Results: The presence of flavonoids, tannins, alkaloids, anthocyanins, mucilages, leuco-anthocyanins and saponosides was noted in the leaves of Jatropha multifida. The aqueous extracts of the leaves inhibited two strains of Staphylococcus aureus out of three, while the sap of Jatropha multifida was 100% bactericidal against the strains of Staphylococcus aureus and Streptococcus D. The sap and aqueous leaf extract were not bactericidal on strains of Escherichia coli, Klebsiella oxytoca and Pseudomonas aeruginosa. For the toxicity, there was no death of rats and the aqueous extract of the leaves did not significantly vary the weight of the rats, the creatinine, the ALAT transaminase, the hemoglobin level, the number of white blood cells and blood platelets. Conclusion: The sap of Jatropha multifida exerted a more effective antibacterial activity than the aqueous extract of its leaves. The leaves were not acutely toxic.

关键词： Jatropha multifida antibacterial activity Toxicity Benin

antibacterial activity of Exogenous Glutathione and Its Synergism on Antibiotics in Methicillin-Associated Multidrug Resistant Clinical Isolates of Staphylococcus aureus

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Advances in Microbiology 2022年第12期12卷 635-648页

作者： Cleiford Senra Minerva A. Garcia Dong H. Kwon Department of Biology Long Island University Brooklyn NY USA

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most problematic human pathogens. Antibiotic treatment of MRSA often associated with resistance to multiple classes of antibiotics is extremely challenging and urgently demands action to treat MRSA. Glutathione (GSH) is a biogenic thiol-compound that maintains an optimal intracellular redox-potential required for various normal cellular processes. antibacterial activity of exogenous GSH has been reported in some bacterial pathogens but is largely unknown in MRSA. Aim: This study aimed to understand antibacterial activity of GSH, its role in antibiotic susceptibility, and a potential antibacterial mechanism in clinical isolates of S. aureus. Materials and Methods: Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), checkerboard, time-killing, and bacterial killing assays were performed for 14 clinical isolates of S. aureus including 10 MRSA and two type strains (ATCC 700699 and 35556). Results: MIC and MBC levels for the clinical and type strains were 15 - 20 mM and 25 - 40 mM of GSH, respectively. Subinhibitory concentrations of GSH synergistically enhanced susceptibility of all tested-antibiotics, resulting in sensitizing all-tested S. aureus. Bacterial-killing produced by GSH-mediated acidity was significantly higher than that by hydrochloric acid-mediated acidity. Conclusion: Overall results concluded that GSH exhibited antibacterial activity on S. aureus regardless of antibiotic susceptibility and synergistically enhanced antibiotic susceptibility. Additionally, GSH-mediated acidity was one of the antibacterial mechanisms. These findings suggest that GSH may be a potential antimicrobial agent or adjuvant for the conventional anti-MRSA regimens.

关键词： Methicillin-Resistant Staphylococcus aureus (MRSA) Multidrug Resistance Glutathione antibacterial activity

antibacterial activity of Silicate Bioceramics

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Journal of Wuhan University of Technology(Materials Science) 2011年第2期26卷 227-231页

作者：扈盛常江 Department of Physical Education Huazhong Normal University Biomaterials and Tissue Engineering Research Center Shanghai Institute of Ceramics

Four kinds of pure silicate ceramic particles,CaSiO3,Ca3SiO5,bredigite and akermanite were prepared and their bactericidal effects were systematically *** phase compositions of these silicate ceramics were characterized by *** ionic concentration measurement revealed that the Calcium （Ca） ion concentration were relatively higher in Ca3SiO5 and bredigite,and much lower in CaSiO3 and ***,the pH values of the four silicate ceramics extracts showed a positive correlation with the particle ***,by decreasing the particle size,higher Ca ion concentrations can be achieved,leading to the increase of aqueous pH value as *** summary,all of the four silicate ceramics tested in our study showed antibacterial effect in a dose-dependent ***,the order of their antibacterial activity against *** from strong to weak is Ca3SiO5,bredigite,CaSiO3 and akermanite.

关键词： silicate ceramics antibacterial activity specific surface area aqueous pH ionic concentration

antibacterial activity of marine bacteria isolated from sponge Xestospongia testudinaria from Sorong,Papua

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Asian Pacific Journal of Tropical Biomedicine 2017年第5期7卷 450-454页

作者： Yatnita Parama Cita Achmad Suhermanto Ocky Karna Radjasa Pratiwi Sudharmono Department of Microbiology Faculty of Medicine Universitas IndonesiaJl.Salemba Raya no 6Jakarta10430Indonesia Maritime and Fishery Polytechnic of Sorong KKD-BP Kesehatan Ikan dan LingkunganJl.K.PattimuraTanjung KasuariP.O.Box 109Sorong98410Papua BaratIndonesia Department of Marine Science Diponegoro UniversitySemarang50275Indonesia

Objective:To explore secondary metabolite of bacteria-associated Xestospongia testudinaria from Tanjung Kasuari,Sorong,***:The antimicrobial activities of extracts against two Gram-positive bacteria(Staphylococcus aureus) and three Gram-negative bacteria(Pseudomonas aeruginosa,Eschericia coli and Salmonella typhi) were determined by disk diffusion dilution ***:The test showed that of 15 isolates of symbiont bacteria,6 isolates were successfully isolated and coded,namely,Xp 4.1,Xp 4.2,Xp 4.3,Xp 4.4,Xp 4.5 and Xp *** the six bacterial isolates,isolated Xp 4.2 was found to have more powerful antibacterial activity than any other isolates of symbiont *** activity assay for the n-hexane soluble fractions,ethyl-acetate soluble fractions,and n-buthanol soluble fractions revealed more powerful anti-bacterial activity than any other soluble *** screening showed alkaloid and steroid/triterpenoid,while identification for isolate of Xp 4.2 bacterial showed ***:Metabolites of bacterial associated with marine sponge Xestospongia testudinaria promise to be developed into antibacterial agents.

关键词： antibacterial activity Marine bacteria Xestospongia testudinaria Sorong

antibacterial activity of the ethyl acetate part of Abrus cantoniensis against Staphylococcus aureus

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Journal of Bio-X Research 2021年第2期4卷 47-52页

作者： Xu Nie Huifang Liu Xinyi Xu Yonghua Zhan Hui Xie Qi Zeng Engineering Research Center of Molecular and Neuro Imaging of the Ministry of Education School of Life Science and TechnologyXidian UniversityXi’anShaanxi ProvinceChina

Objective:The aim of this work was to measure the antibacterial activity(against Escherichia coli and Staphylococcus aureus[***])of the ethyl acetate part of Abrus cantoniensis and assess their potential as ***:The experiment was divided into four groups:negative control group[with Mueller-Hinton broth(MHB)],positive control group(with 75%ethanol),blank group(with MHB)and test group(with the ethyl acetate part of Abrus cantoniensis).The antibacterial activities of the extracts were evaluated by the Oxford cup assay and minimum inhibitory concentration(MIC).Time-kill curve experiments,scanning electron microscopy,the content of DNA,RNA and protein were used to study the antibacterial mechanism of the ethyl acetate extract part on the growth and viability of *** study procedures were approved by the Animal Care and Use Committee of Xi’an Jiaotong University(approval ***2016-412)on January 22,***:The ethyl acetate part of Abrus cantoniensis extract exhibited the highest inhibitory activity against the growth of *** with an inhibition zone diameter of 16.4mm and MIC value of 0.5mg/*** general activity range of the ethyl acetate part,determined using a time-killing curve,was found to be 0.5mg/mL to 40mg/mL(MIC to 80MIC).Changes in the scanning electron microscopy images and of DNA,RNA and proteins of *** indicated possible mechanisms of the inhibitory activity of the ethyl acetate ***:The ethyl acetate part of Abrus cantoniensis damaged bacterial cell structures,which results in protoplasm leakage,and eventually bacterial cell death.

关键词： Abrus cantoniensis antibacterial activity ethyl acetate extract Staphylococcus aureus time-kill curve

antibacterial activity and Structure-activity Relationships of Schiff Bases on Staphylococcus aureus by Microcalorimetry

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Wuhan University Journal of Natural Sciences 2010年第1期15卷 71-77页

作者： HOU Hanna ZHU Juncheng QI Zude ZHOU Bo LI Meiying LIU Yi College of Chemistry and Molecular Sciences/State Key Laboratory of Virology Wuhan University Wuhan 430072 Hubei China Department of Chemistry Hubei University of Education Wmhan 430205 Hubei China

The growth of Staphylococcus aureus under the action of six kinds of Schiff bases（A,B,C,D,E,F） was studied by means of microcalorimetry. Growth constant k and inhibition ratio I were calculated. Also,the antibacterial activity,the action characteristics and the structure-activity relationships of the compounds on S. aureus were analyzed. Results indicate that B,F show good antibacterial activity（IC50：293.6 mg · L-1 and 307.8 mg · L-1） ,D,E show moderate antibacterial activity（IC50：966.3 mg · L-1 and 1 126.7 mg · L-1） ,and A,C just show weak antibacterial activity（IC50 〉1 200 mg · L-1） . The I-c curves mainly present a straight line shape for B,D,E and F,but an inverse ＂S＂ shape for A and C. Structure-activity relationships analysis suggests that the species and position of the substituents determine the antibacterial activity of these Schiff bases,and the charge density distribution is one of the most important influencing factors.

关键词： Schiff bases Staphylococcus aureus microcalorimetry antibacterial activity structure-activity relationships

Synthesis and antibacterial activity of Novel Oxazolidinone Analogs Containing Substituted Thiazole/Fused-Bicyclic Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 459-464页

作者： ZHAI Xin ZHAO Yan-fang WANG Jia HONG Wei HUANG Liang GONG Ping School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 P. R. China

Sixteen novel oxazolidinone analogs containing substituted thiazole/fused-bicyclic（imidazo[ 1,2-b] pyridazine/ imidazo[2,1-b] thiazole） groups were designed and synthesized. A new method for the preparation of the key intermediate compound 11 was proposed. The structures of the target compounds were confirmed by ^1H NMR, IR and MS, and their in vitro antibacterial activities against staphylococcus aureus were evaluated. Among them, compound 16a displays a promising antibacterial activity comparable to that of linezolid.

关键词： Oxazolidinone analog Synthesis antibacterial activity

Structure and antibacterial activity of Ce3+ exchanged montmorillonites

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Journal of Rare Earths 2009年第5期27卷 858-863页

作者： OUYANG Yousheng XIE Yushan TAN Shaozao SHI Qingshan CHEN Yiben Guangdong Institute of Microbiology Guangzhou 510070 China Department of Chemistry Jinan University Guang1zhou 510632 China Department of Chemistry Jinan University Guang1zhou 510632 China Guangdong Institute of Microbiology Guangzhou 510070 China Guangdong Institute of Microbiology Guangzhou 510070 China

Four kinds of Ce3+ exchanged montmorillonites (Ce/MMTs) were prepared by an ion-exchange reaction, and characterized with energy dispersive X-ray analysis (EDX), X-ray difference (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The surface properties and antibacterial activity of Ce/MMTs were also investigated. The chemical compositions of Ce/MMTs were determined, and the cerium of Ce/MMTs was confirmed to be present as trivalent cerium state. The d001 basal spacings of Ce/MMTs were enlarged with the enhancement of the cerium contents, and the particles were formed with irregular shape. On increasing the Ce contents of Ce/MMTs, the special surface areas were decreased, but the total pore volumes and the average pore sizes were increased. The antibacterial activity of Ce/MMTs is increased with increasing the cerium contents, and 1.5 g/L of Ce/MMT-3 containing 11.46wt.% of curium could remove all the Staphylococcus aureus and more than 99.9% of the Escherichia coli within 24.0 h of contact. Moreover, Ce/MMTs displayed bactericidal activity.

关键词： Ce3+ exchanged montmorillonite chemical composition microstructure antibacterial activity rare earths

Influence of Doping Ions on the antibacterial activity of Biomimetic Coating on CoCrMo Alloy

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Journal of Bionic Engineering 2015年第4期12卷 583-591页

作者： Georgeta Totea Daniela Ionita Ioana Demetrescu Faculty of Applied Chemistry and Materials Science Department of General Chemistry University Politehnica of Bucharest 1-7 Polizu district 1 Bucharest Ro-O 11061 Romania

In this study biomimetic fluoridated phosphate doped hydrophilic coatings with various ions on CoCrMo alloy were pre- pared by electrodeposition. Cu and Zn ions were chosen for doping because of their well known antibacterial activity. The struc^xes of the coatings were identified using Fourier-transform Infrared （FTIR） analysis. X-ray Diffraction （XRD） analysis was performed to evaluate crystallite dimensions of the specimen surface. The contact angle was measured in order to establish the hydrophilic/hydrophobic balance and to compute surface energy. All studied samples have a hydrophilic character which is weaken after doping. The time evolution of ions releasing from the coatings was evaluated with an inductively plasma mass spectrometer after immersion in saline phosphate. The hemolytic experiments indicate that except the fluoridated coatings doped with Zn which is slightly hemolytic, all other samples are non hemolytic. The test for antibacterial activity for Staphy- lococcus aureus and Pseudomonas aeruginosa indicated that the fluoridated biomimetic coating doped with various positive ions increases bacterial growth inhibition level significantly. Fluoridated phosphate coating doped with Cu has best antibacterial activity

关键词： phosphate coating electrodeposition CoCrMo alloy doping ions antibacterial activity