antimicrobial

This study was performed to evaluate the presence of Phytochemical, antimicrobial and antioxidant activity of Eria pseudoclavicaulis Blatt. (Orchidaceae) leaf extracts. Preliminary phytochemical analysis revealed that the ethyl acetate extract shown the maximum phytochemical constituents followed by ethanol and water. Different extracts of Eria pseudoclavicaulis were tested for antimicrobial activity of this, ethyl acetate extract shown the maximum antibacterial activity against five microorganisms. The water extract possess strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (IC50 318 μg/ml), This research findings suggest that Eria pseudoclavicaulis exhibits potential antimicrobial and antioxidant properties. Key words: phytochemical analysis, antimicrobial, antioxidant, Eria pseudoclavicaulis  

Mixture of three compounds lupeol acetate (1), alpha amyrin acetate(2) and beta amyrin acetate(3) were isolated from the methanolic extract of the stem bark of Artocarpus lackoocha Roxb.(Family: Moraceae).The crude methanol extract as well as its petroleum ether, carbon tetrachloride; chloroform and aqueous soluble Kupchan fractions were studied for antioxidant, antimicrobial and cytotoxic activities. Among the different fractions tested for antioxidant activity, the aqueous soluble partitionate was the most potent with IC50 value of 3.47μg/ml as compared to tertbutyl-1-hydroxytoluene (IC50=27.54μg/ml). Antimicrobial screening of the different extractives was conducted by the disc diffusion method and the crude methanol extract as well as aqueous soluble fractions exhibited moderate antimicrobial activity with zone of inhibition ranging from 7-12 mm. In brine shrimp lethality bioassay, the aqueous soluble materials demonstrated the highest toxicity with LC50 of 1.6μg/ml. β-amyrin acetate is the first report of isolation of compounds from Artocarpus lackoocha.

Dental implant is a pharmaceutical device in the form of strip with very small loading and size of 0.25 sq cm. For site-specific one-time continuous delivery of Gatifloxacin an antimicrobial compound with excellent activity against anaerobic micro-organism in the treatment of periodontal disease was prepared by solvent casting technique using ethyl cellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose K4M and Eudragit RL-100 with dibutylphthalate as plasticizer. The physicochemical parameters like thickness, weight variation, content uniformity and release characteristics were evaluated The drug release was initially high on day one to achieve immediate therapeutic level of drug in pocket, followed by marked fall in release by day two, and progressive moderate release profile to maintain therapeutic level following anomalous transport mechanism. Formulation F6 released 97.34% of drug at the end of 144 h and was considered as best formulation. In vitro antibacterial activity was carried out on Streptococcus mutans .

An antimicrobial activity of Omphalotus olivascens wild mushroom was evaluated. The mycelia culture filtrate extracts showed varying degree of inhibition on the test organisms (Bacillus cereus, Escherichia coli, Salmonella paratyphi A, Klebsiella pnemoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Candida albicans).  The antimicrobial activity of mushroom sample varied according to the solvents. The ethyl acetate extract was the most active when compared with other extracts, to inhibit the growth of Acinetobacter baumannii (32mm), Klebsiella pnuemoniae (31mm), Bacillus cereus (31mm), and E.coli (28mm), Pseudomonas aeruginosa (28mm) Salmonella paratyphi A (27mm) and Canidida albicans (24mm). The bioactive contents of the mushroom are promising natural antimicrobial agents that can be harnessed as antimicrobial toxicants.

Dental caries is the major public health problem that disturbs all countries in the world. Streptococcus mutans is considered as a chief culprit of this infectious disease and biofilm formation potential is the major virulence trait of this pathogen. In the era of antimicrobial resistance it is important to understand the virulence mechanism and antimicrobial sensitivity of S. mutans globally. The objective of the study was to investigate the biofilm formation potential and antimicrobial sensitivity of clinical isolates of S. mutans. Biofilm formation potential of 100 clinical isolates was studied by microtiter plate assay and coverslip assay and antimicrobial sensitivity was assessed by disc diffusion method. Our results showed that out of 100 clinical isolates 92 (92%) showed strong biofilm forming capability and 8 (8%) clinical isolates showed moderate biofilm formation potential. Antimicrobial sensitivity results showed that 72 (72%) isolates were resistant to amoxicillin, 65 (65%) isolates were resistant to chloramphenicol, 40 (40%) isolates were resistant to doxicycline, 46 (46%) isolates were resistant to erythromycin, 32 (32%) isolates were resistant to ofloxacin, 61 (61%) isolates were  resistant to tetracycline and only 17 (17%) isolates of S. mutans were resistant to amoxicillin/clavulanate. Our results suggest that combination therapy is more effective against cariogenic S. mutans and biofilm formation potential of this organism indicates the powerful contribution in pathogenesis. Ultimately, new combination therapies and inhibitors of biofilm formation are urgently needed. Key words: antimicrobial, biofilm, dental caries, S. mutans, therapy, virulence

  A series of thiophene and aryl substituted compounds 1a-f; 2a-b and 3a-c were synthesized by Erlenmeyer azolactone synthesis. These compounds were screened for antimicrobial activity method in vitro. Among the tested compounds 3c showed significant activity and some of the other compounds showed promising activity. The structure of new compounds synthesized during present investigation have been authentically established by their IR,1H NMR and Mass spectra and some QSAR studies. Key words: Thiophene; antimicrobial; antibacterial; antifungal.