Isolation and screening of bioactive principle from Chaetomorpha antennina against certain bacterial strains

Microbial pathogens develop resistance to a particular antibiotic after repeated administration during the treatment of infectious diseases. Moreover, multiple drug resistance is a very common problem especially in hospital acquired infections. Therefore, it is necessary to find out alternative antibacterial drugs and the present trend is focused on seaweeds. This preliminary research work was carried out to find out the antibacterial activity of petroleum ether extract of Chaetomorpha antennina. The extracts were tested against Staphylococcus aureus MTCC 121, Bacillus cereus MTCC 492, Bacillus subtilis MTCC 441, Klebsiella pneumoniae MTCC 530, Escherichia coli MTCC 443 and Pseudomonas aeruginosa MTCC 779 by agar well diffusion technique. It was observed that petroleum ether extract showed prominent zone of inhibition against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus even at 50 μg/ml concentration. The maximum spectrum of activity was observed against Staphylococcus aureus ranged from 7.3 ± 0.8 to 18 ± 2.4 mm at the concentration 50 to 500 μg/ml, respectively. Hence the most susceptible bacterium was Staphylococcus aureus among the tested organisms. However, Escherichia coli and Pseudomonas aeruginosa are also susceptible. But the Bacillus cereus and Klebsiella pneumoniae are resistant against the tested extract.     

Screening of Iranian Plants for Antimicrobial Activity

The methanol extracts of 306 plants of 52 families obtained from Northeast of Iran (Khorasan Province), were tested for antimicrobial activity (in vitro) using the cylinder plate assay method. Activity against Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Pseudomonas aeruginosa, Morganella morganii (Gram negative), Bacillus subtilis and Staphylococcus aureus (Gram positive) and Candida albicans is discussed.     

Antibacterial and antioxidant activity of methanol extract of Evolvulus nummularius

Objective:

To evaluate the antibacterial and antioxidant activity of methanol extract of Evolvulus nummularius (L) L.

Materials and Methods:

Disc diffusion and broth serial dilution tests were used to determine the antibacterial activity of the methanol extract against two Gram-positive bacterial strains (Bacillus subtilus NCIM 2718, Staphylococcus aureus ATCC 25923) and three Gram-negative bacterial strains (Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 and Escherichia coli ATCC 25922). The methanol extract was subjected to preliminary phytochemical analysis. Free radical scavenging activity of the methanol extract at different concentrations was determined with 2, 2-diphenyl-1picrylhydrazyl (DPPH).

Results:

The susceptible organisms to the methanol extract were Escherichia coli (MIC=12.50 mg/ml) and Bacillus subtilus (MIC=3.125 mg/ml) and the most resistant strains were Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa. The methanol extracts exhibited radical scavenging activity with IC50 of 350 μg/ml.

Conclusion:

The results from the study show that methanol extract of E.nummularius has antibacterial activity. The antioxidant activity may be attributed to the presence of tannins, flavonoids and triterpenoids in the methanol extract. The antibacterial and antioxidant activity exhibited by the methanol extract can be corroborated to the usage of this plant in Indian folk medicine.     

Antibacterial Activity of the Iraqi Rheum ribes. Root

Abstract

The antibacterial activity of the ethanol, aqueous, and organic extracts from the root of Rheum ribes. Linn (Polygonaceae) was examined. Four anthraquinone aglycone components, chrysopahnol, physcion, aloe emodin, and emodin, were isolated from the biologically active extract and identified by spectroscopic analysis. Emodin is recorded for the first time in this species. The MIC values of the biologically active extracts, aloe emodin, and emodin, were 500, 125, 250, and 63 µg/mL against Staphylococcus aureus., respectively. The extracts and compounds did not inhibit Pseudomonas aeruginosa. and Escherichia coli. at the highest concentration tested, 4000 and 250 µg/mL, respectively.     

Antimicrobial Studies on Extracts of Four Species of Stachys

The antimicrobial activity of the methanol extracts of the dried flowering aerial parts of Stachys byzantina, S. inflata, S. lavandulifolia and S. laxa (Labiatae) were studied using the disc diffusion method and determination of minimum inhibitory concentration (MIC) values against Staphylococcus aureus, Streptococcus sanguis, Escherichia coli, Pseudomonas aeroginosa, Klebsiella pneumoniae, Aspergilus niger and Candida albicans. The extracts of plants exhibited concentration-dependent antibacterial activity against the bacteria tested. The extracts were more active against Gram-positive microorganisms. The extracts, however, did not show any antifungal activity.     

Antimicrobial Activities of Malaysian Plant Species

Antimicrobial activities against reference Gram-positive (Staphylococcus aureus, Enterococcus faecalis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria and Candida albicans were tested on 191 plant extracts obtained from more than 30 families of plants found in the state of Sabah, Malaysia. The plant extracts were tested by a disk-diffusion technique in which antimicrobial activity was evaluated based on the ability of the plant extracts to diffuse through agar to affect the target organisms. The extracts of Callicarpa erioclona Schau. (Verbenaceae), Callicarpa farinosa Roxb. (Verbenaceae), Sphonodesma friflora Wright (Verbenaceae), and Homalium panayanum F. Villar (Flacourticeae) exhibited antimicrobial properties worthy of further investigation.     

Quality control,phytochemical profile,and biological activities of Crataegus monogyna Jacq. and Crataegus laciniata Ucria fruits aqueous extracts

The current study aimed to evaluate the phytochemical composition, quality control, and antioxidant, antibacterial, antifungal, antihyperglycemic activities, and toxicity assessment of Crataegus monogyna Jacq (C. monogyna) and Crataegus laciniata Ucria (C. laciniata) fruits aqueous extracts. The quality control of the plant material revealed that it is free of heavy metals and the acidity and ash parameters comply with international standards. HPLC-DAD analysis revealed the presence of eight phenolic compounds in the C. monogyna extract and nine compounds in the C. laciniata extract, with coumaric acid present only in the C. laciniata extract. According to the findings, both extracts are high in total polyphenols, total flavonoids, and condensed tannins. The results of the antioxidant activity revealed that our extracts have significant effects against 2, 2-diphényl 1-picrylhydrazyle (DPPH), and Ferric Reducing Antioxidant Power (FRAP). The antibacterial test revealed that the two extracts tested were effective against four bacterial strains, including Staphylococcus aureus, Escherichia coli, Enterobacter cloacae, and Shigella dysenteria, but were ineffective against Salmonella typhi, and Acinetobacter baumanii. In addition, extracts from both plants showed remarkable antihyperglycemic activity with no acute toxicity. In conclusion, the extracts studied could be a good source of bioactive molecules with antioxidant, antimicrobial, and anti-diabetic activity for pharmaceutical applications.     

Antibacterial activity and interactions of plant essential oil combinations against Gram-positive and Gram-negative bacteria

The aim of this study was to compare the antibacterial effects of several essential oils (EOs) alone and in combination against different Gram-positive and Gram-negative bacteria associated with food products. Parsley, lovage, basil, and thyme EOs, as well as their mixtures (1:1, v/v), were tested against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium. The inhibitory effects ranged from strong (thyme EO against E. coli) to no inhibition (parsley EO against P. aeruginosa). Thyme EO exhibited strong (against E. coli), moderate (against S. typhimurium and B. cereus), or mild inhibitory effects (against P. aeruginosa and S. aureus), and basil EO showed mild (against E. coli and B. cereus) or no inhibitory effects (against S. typhimurium, P. aeruginosa, and S. aureus). Parsley and lovage EOs revealed no inhibitory effects against all tested strains. Combinations of lovage/thyme and basil/thyme EOs displayed antagonistic effects against all bacteria, parsley/thyme EOs against B. cereus, S. aureus, P. aeruginosa, and E. coli, and lovage/basil EOs against B. cereus and E. coli. Combinations of parsley/lovage and parsley/basil EOs exhibited indifferent effects against all bacteria. The combination of lovage/basil EO showed indifferent effect against S. aureus, P. aeruginosa, and S. typhimurium, and the combination parsley/thyme EO against S. typhimurium. Thyme EO has the highest percentage yield and antibacterial potential from all tested formulations; its combination with parsley, lovage, and basil EOs determines a reduction of its antibacterial activity. Hence, it is recommended to be used alone as the antibacterial agent.     

Quercus infectoria. Oliv.

Abstract

Bacterial resistance to antibiotics is enhanced by unrestricted use of such drugs. In addition, stimulating effects of certain antibiotics on the production of verocytotoxin by enterohemorrhagic Escherichia coli. have been reported. The aim of this communication was to report a medicinal plant species that is effective against a broad range of bacteria of clinical importance including Acinetobacter baumannii., Bacillus cereus., Enterobacter faecalis., Escherichia coli., Helicobacter pylori., Klebsiella pneumoniae., Listeria monocytogenes., Pseudomonas aeruginosa., Salmonella. spp., Shigella flexneri., Staphylococcus aureus., Streptococcus mutans., and Streptococcus pyogenes.. Ethanol extracts of Quercus infectoria. Oliv. (Fagaceae) demonstrate a broad spectrum of activity against all bacterial species tested. Detailed studies were carried out on clinical isolates of pathogens commonly presenting problems with the use of antibiotics, including enterohemorrhagic Escherichia coli. (EHEC), methicillin-resistant Staphylococcus aureus. (MRSA), multidrug-resistant Klebsiella pneumoniae., multidrug-resistant Helicobacter pylori., and Salmonella.spp. The extracts of Quercus infectoria. displayed remarkable activity against MRSA with MICs ranging from 0.02 to 0.4 mg/mL, and MBCs ranging from 0.4 to 1.6 mg/mL. More importantly, this plant species could exhibit strong antibacterial activity against all Gram-Negative organisms. Its significant activity was shown with EHEC, with MICs of 0.05 to 0.1 mg/mL and MBCs of 0.8 to 1.6 mg/mL. The results from this study indicate that Quercus infectoria. is potentially a good source of antibacterial substances with broad spectrum of activities against antibiotic-resistant bacteria.     

2018—2020年郑州市第七人民医院血流感染分离菌的分布及耐药性分析

目的 了解血流感染分离菌的分布及耐药特征,为临床防治血流感染提供指导和依据。方法 收集2018年1月—2020年12月郑州市第七人民医院血培养分离的非重复菌株,采用WHONET5.6软件统计菌株的分布及耐药特征。结果 共分离546株菌株,革兰阴性菌302株（55.31%）,革兰阳性菌220株（40.29%）,真菌24株（4.40%）。前6位分离菌依次为凝固酶阴性葡萄球菌（CNS,23.44%）、大肠埃希菌（18.68%）、肺炎克雷伯菌（14.84%）、金黄色葡萄球菌（6.04%）、鲍曼不动杆菌（4.21%）和铜绿假单胞菌（3.85%）。大肠埃希菌对碳青霉烯类最敏感,肺炎克雷菌碳对美罗培南和亚胺培南的耐药率分别为30.86%和35.80%,鲍曼不动杆菌耐药较严重,耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）和耐甲氧西林金黄色葡萄球菌（MRSA）的检出率分别为72.66%、42.42%,未发现利奈唑胺和万古霉素耐药的葡萄球菌。结论 革兰阴性菌是医院血流感染的主要致病菌,细菌耐药情况复杂,临床要根据药敏结果合理选择抗菌药物。     

2016—2021年清镇市第一人民医院神经外科患者下呼吸道标本病原菌分布特征及耐药性分析

目的 探讨清镇市第一人民医院神经外科患者下呼吸道标本病原菌构成特点及耐药情况,为临床合理使用抗菌药物治疗提供参考依据。方法 收集2016年1月—2021年12月清镇市第一人民医院神经外科患者送检的合格下呼吸道标本,采用梅里埃VITEK 2-compact分析仪进行细菌鉴定和药物敏感性试验。结果 共检出663株细菌,其中革兰阴性杆菌有556株,占比83.9%;革兰阳性球菌有107株,占比16.1%;常见病原菌为肺炎克雷伯菌（214株,32.3%）、鲍曼不动杆菌（93株,14.0%）、金黄色葡萄球菌（91株,13.7%）、铜绿假单胞菌（80株,12.1%）和大肠埃希菌（61株,9.2%）。耐药性监测结果显示,肺炎克雷伯菌和大肠埃希菌产超广谱β-内酰胺酶（ESBLs）菌株分别占33.1%、60.6%,对碳青霉烯类药物的耐药率为8.9%、1.6%;鲍曼不动杆菌对氨曲南、头孢他啶、氨苄西林/舒巴坦、环丙沙星和头孢吡肟的耐药率超过60.0%,对亚胺培南的耐药率为53.8%;铜绿假单胞菌对庆大霉素、阿米卡星和妥布霉素的耐药率低于15.0%,对亚胺培南的耐药率为45.0%。金黄色葡萄球菌中甲氧西林耐药金黄色葡萄球菌（MRSA）检出率为62.6%,MRSA的耐药率明显高于甲氧西林敏感金黄色葡萄球菌（MSSA）,未检出对替加环素、万古霉素和利奈唑胺耐药的菌株。结论 清镇市第一人民医院神经外科患者下呼吸道感染病原菌以革兰阴性杆菌为主,肺炎克雷伯菌、鲍曼不动杆菌、金黄色葡萄球菌、铜绿假单胞菌和大肠埃希菌是常见的病原菌。病原菌对临床常用抗菌药物耐药严重,多重耐药细菌检出率高,临床用药治疗前应及时采样进行细菌培养和药物敏感性试验,根据药敏试验结果制定合理的治疗方案。     

Antimicrobial susceptibility of Gram-positive non-urinary isolates to fosfomycin

We aimed to evaluate the antimicrobial activity of fosfomycin against Gram-positive non-urinary isolates collected at the microbiological laboratory of the University Hospital of Heraklion, Crete, Greece, in 2008. Susceptibility testing was performed by the disk diffusion method for a total of 1846 isolates; 1275 isolates (69.1%) were susceptible to fosfomycin. Specifically, 416/419 Staphylococcus aureus (99.3%) [including 129/130 meticillin-resistant S. aureus (MRSA) isolates] and 745/961 coagulase-negative staphylococci (77.5%) were susceptible to fosfomycin. Among 42 Streptococcus pneumoniae, 64 Streptococcus pyogenes and 93 other streptococcal isolates, 61.9%, 40.6% and 48.4%, respectively, were susceptible to fosfomycin. Fosfomycin was inactive against the 166 enterococcal isolates tested. This old antibiotic may deserve consideration for further studies and use in clinical practice, especially for S. aureus (including MRSA) infections.     

Antimicrobial screening of essential oils and extracts of someHumulus lupulus L. cultivars

The essential oils as well as solvent extracts of 11 hop cultivars, 1 hop variety and a wild type of hop were screened for their antimicrobial activities using the agar overlay technique. The oils were isolated from the cones of the various hop plants by hydrodistillation, the extracts were obtained by soaking the hop cones in chloroform. The oils and the extracts showed activity against the Gram-positive bacteria (Bacillus subtilis andStaphylococcus aureus) and the fungus (Trichophyton mentagrophytes var.interdigitale), but almost no activity against the Gram-negative bacterium (Escherichia coli) and the yeast (Candida albicans) used in the screening. The peak area percentages of the main volatile components and the contents of the bitter acids of the extracts were determined for all cultivars using chromatographic methods.     

Synthesis and characterization of biocompatibility of tenorite nanoparticles and potential property against biofilm formation

Aim is to assess the anti-biofilm property of tenorite nanoparticles and to study their suitability as a possible coating material for medical implants. Tenorite (CuO) nanoparticles were synthesized by the optimized thermal decomposition method and characterized using TEM, XRD, FTIR and UV–Vis analysis. Their influence on biofilm formation of microbes was studied by growing multi drug resistant bacterial strains in the presence or absence of these nanoparticles at various concentrations. The cytotoxicity of nanoparticles on mammalian cells was studied at the corresponding concentrations. The nanoparticles were found to be uniformly dispersed, spherical shaped and <50 nm in size. They showed various degrees of anti-biofilm property against clinically isolated, biofilm forming multi drug resistant microorganisms such as Staphylococcus aureus, Pseudomonas fluorescens, Burkholderia mallei, Klebsiella pneumoniae, and Escherichia coli. Furthermore, Hep-2 cells showed excellent viability at tenorite nanoparticles concentration toxic to microbial growth. These results indicate that tenorite nanoparticles may be ideal candidates for being utilized as coating on medical implants in general and dental implants in particular.     

Novel arylhydrazone derivatives bearing a rhodanine moiety: synthesis and evaluation of their antibacterial activities

A series of arylhydrazone derivatives bearing a rhodanine moiety have been synthesized, characterized, and evaluated as antibacterial agents. Some of these compounds showed potent antibacterial activities against several different strains of Gram-positive bacteria, including multidrug-resistant clinical isolates. Of the compounds tested, IIk and IIIk were identified as the most effective, with minimum inhibitory concentration values of 2–4 μg/mL against multidrug-resistant Gram-positive organisms, including methicillin-resistant and quinolone-resistant Staphylococcus aureus. None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 at 64 μg/mL.     

Synthesis,antibacterial evaluation,and SAR study of some novel 3-aryl/heteroaryl-9-methyl-1,2,4-triazolo-[4,3-<Emphasis Type="Italic">a</Emphasis>]-quinoline derivatives

A series of new quinolin-2-yl moiety linked hydrazones of various aryl/heteroaryl aldehydes has been prepared which on treatment with iodobenzene diacetate in dichloromethane yielded novel triazolo[4,3-a]quinoline derivatives. All the synthesized compounds were characterized on the basis of their FT-IR, ¹H, ¹³C NMR, and mass spectral data. Compounds thus obtained were tested in vitro for their antibacterial activity against three Gram-positive bacterial, namely Enterococcus, Bacillus subtilis, and Staphylococcus aureus, and three Gram-negative bacterial strains, namely Psuedomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae using agar well diffusion method. The percentage similarity of all compounds was also assessed on the basis of physico-chemical and steric parameters as compared to a standard drug, Cefixime using Chem 3D software. Most of the compounds possessed good percentage similarity and exhibited admirable antibacterial activity when compared with the standard drug. Compounds (4a, 4b, 3a, 3c, and 3d) containing pyrazole moiety were found to be most effective against Gram-positive bacteria, S. aureus and B. subtilis.     

高龄妇女剖宫产术后感染病原菌及耐药性趋势分析

目的 了解高龄产妇剖宫产术后感染的病原菌种类及耐药性趋势。方法 以3年为一时间段,对2007年1月-2015年12月进行剖宫产术后继发感染的高龄产妇的切口分泌物进行细菌培养和药敏试验。结果 2007-2009年、2010-2012年和2013-2015年分别分离出菌株77株、74株和75株,病原菌以金黄色葡萄球菌、凝固酶阴性葡萄球菌、大肠埃希菌和铜绿假单胞菌较为常见。细菌分布动态提示,革兰阳性菌感染呈逐渐下降趋势,而革兰阴性菌感染逐渐增加,其中以大肠埃希菌感染比例上升最为明显。药敏结果提示,革兰阳性菌对万古霉素、利福平耐药性较低,大肠埃希菌、铜绿假单胞菌等革兰阴性菌对亚胺培南、美罗培南、哌拉西林钠他唑巴坦钠、头孢哌酮钠舒巴坦钠和阿米卡星等耐药性较低。耐药性动态提示,金黄色葡萄球菌对头孢曲松、左氧氟沙星的耐药性上升明显,大肠埃希菌对左氧氟沙星耐药性上升明显,铜绿假单胞菌对哌拉西林钠他唑巴坦钠和头孢他啶耐药性上升明显。结论 高龄产妇剖宫产术后感染以金黄色葡萄球菌、凝固酶阴性葡萄球菌、大肠埃希菌和铜绿假单胞菌为主,革兰阳性菌感染呈逐渐下降趋势,而革兰阴性菌感染逐渐增加。药敏结果显示,致病菌对常用抗菌药物的多重耐药性严重,临床应合理使用抗菌药物。     

In-silico design, synthesis and evaluation of novel DNA-gyrase B inhibitors

2-Quinolones are an important class of compounds, isomeric to 4-quinolones. They may become promising candidates for exploiting more useful therapeutically active molecules. DNA-gyrase has drawn much attention as a selected target for finding potent anti-bacterial agents against multi-drug resistant strains such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and penicillin-resistant Streptococci pneumonia. The objective of the present study was to study the molecular docking simulations on 2-quinolone analogs as probable candidates for inhibiting DNA gyrase subunit-B of S. aureus. In the present study, docking simulations were carried out on the reported inhibitors of DNA-gyrase subunit A and B using docking software. Based on it, series of 2-quinolone analogs (compound 1–8) were designed, synthesized, characterized, and evaluated for their anti-bacterial activity against S. aureus and E. coli. Out of the eight test compounds, compound-2 showed good anti-bacterial activity against S. aureus and E. coli as compared with the rest of the other compounds. The rational approach to lead discovery has prompted a better insight into developing more specific 2-quinolones as potential antibacterial agents.     

Surveillance of tigecycline activity tested against clinical isolates from a global (North America,Europe, Latin America and Asia-Pacific) collection (2016)

Tigecycline and comparators were tested by the reference broth microdilution method against 33 348 non-duplicate bacterial isolates collected prospectively in 2016 from medical centres in the Asia-Pacific (3443 isolates), Europe (13 530 isolates), Latin America (3327 isolates) and the USA (13 048 isolates). Among 7098 Staphylococcus aureus isolates tested, >99.9% were inhibited by ≤0.5?mg/L tigecycline (MIC_50/90, 0.06/0.12?mg/L), including >99.9% of methicillin-resistant S. aureus and 100.0% of methicillin-susceptible S. aureus. Tigecycline was slightly more active against Enterococcus faecium (MIC_50/90, 0.03/0.06?mg/L) compared with Enterococcus faecalis (MIC_50/90, 0.06/0.12?mg/L) and its activity was not adversely affected by vancomycin resistance when tested against these organisms. Tigecycline potency was comparable for Streptococcus pneumoniae (MIC_50/90, 0.03/0.06?mg/L), viridans group streptococci (MIC_50/90, 0.03/0.06?mg/L) and β-haemolytic streptococci (MIC_50/90, 0.06/0.06?mg/L) regardless of species and penicillin susceptibility. Tigecycline was active against Enterobacteriaceae (MIC_50/90, 0.25/1?mg/L; 97.8% inhibited at ≤2?mg/L) but was slightly less active against Enterobacteriaceae isolates expressing resistant phenotypes: carbapenem-resistant Enterobacteriaceae (MIC_50/90, 0.5/2?mg/L; 98.0% susceptible); multidrug-resistant (MIC_50/90, 0.5/2?mg/L; 93.1% susceptible); and extensively drug-resistant (MIC_50/90, 0.5/4?mg/L; 87.8% susceptible). Tigecycline inhibited 74.4% of 888 Acinetobacter baumannii isolates at ≤2?mg/L (MIC_50/90, 2/4?mg/L) and demonstrated good in vitro activity against Stenotrophomonas maltophilia (MIC_50/90, 1/2?mg/L; 90.6% inhibited at ≤2?mg/L) Tigecycline was active against Haemophilus influenzae (MIC_50/90, 0.12/0.25?mg/L) regardless of β-lactamase status. Tigecycline represents an important treatment option for resistant Gram-negative and Gram-positive bacterial infections.     

Antibacterial Activity of some Medicinal Mangroves against Antibiotic Resistant Pathogenic Bacteria

The antibacterial activity of the leaves and bark of mangrove plants, Avicennia marina, A. officinalis, Bruguiera sexangula, Exoecaria agallocha, Lumnitzera racemosa, and Rhizophora apiculata was evaluated against antibiotic resistant pathogenic bacteria, Staphylococcus aureus and Proteus sp. Soxhlet extracts of petroleum ether, ethyl acetate, ethanol and water were prepared and evaluated the antibacterial activity using agar diffusion method. Most of the plant extracts showed promising antibacterial activity against both bacterial species. However, higher antibacterial activity was observed for Staphylococcus aureus than Proteus sp. The highest antibacterial activity was shown by ethyl acetate of mature leaf extracts of E. agallocha for Staphylococcus aureus. All ethyl acetate extracts showed higher inhibition against S. aureus while some extracts of chloroform, ethyl acetate and ethanol gave inhibition against Proteus sp. None of the petroleum ether and aqueous extracts showed inhibition against Proteus sp. All fresh plant materials did also show more antibacterial activity against both bacterial strains than did dried plant extracts. Antibacterial activity of fresh and dried plant materials reduced for both bacterial strains with time after extraction. Since L. racemosa and A. marina gave the best inhibition for bacterial species, they were used for further investigations. Charcoal treated plant extracts of L. racemosa and A. marina were able to inhibit both bacterial strains more than those of untreated plant extracts. Phytochemical screening of mature leaf, bark of L. racemosa and leaf extracts of A. marina has been carried out and revealed that leaf and bark contained alkaloids, steroids, triterpenoids and flavonoids. None of the above extracts indicate the presence of saponins and cardiac glycosides. Separated bands of extracts by TLC analysis showed antibacterial activity against S. aureus.