Asian Journal of Pharmaceutical Research and Health Care

M. Srinu , M. Murali Krishna Kumar , G. Girija Sankar

Abstract

In our screening program for new bio-active metabolites from marine actinomycetes, a cyclic depsipeptide was found in the fermentation medium of marine Strepromyces (SS23/4) isolated from sediments collected from Bay off Bengal, vellampattai,Tamilnadu. It showed strong biological activity against gram-positive / gram negative bacteria by agar overlay technique. It was taxonomically characterized by the basis of morphological and phenotypic characteristics, genotypic data and phylogenetic showing Streptomyces sps. Bio active compound was obtained by solvent extraction and purification using column chromatography followed by reverse phase HPLC. The pure compound had potent activity against Mycobacterium tuberculosis and Multi Drug Resistant Mycobacterium tuberculosis strains (437RU) at a concentration of 10 μg/mL, and The minimum inhibitory concentration (MIC) against standard test organisms was found to be 1μg/mL against B.subtilis, E.coli and Methicillin resistant Staphylococcus aureus. The compound exhibited potent cytotoxic activity against breast carcinoma (MCF-7), melanoma cells (A375), prostate carcinoma (DU145) and lung carcinoma (A549) cells with IC values 20μg/ml. The symbiotic Streptomyces capillispiralis MTCC 10471 produces crude antibiotic 30mg/Lt by using nonoptimized fermentation conditions. The structure of the antibiotic was explained by 1D, 2D NMR and LC-ESI-MS/MS, MALDI-TOF/MS experiments, revealed that it belongs to cyclic ploy peptide Actinomycin D.

Keywords

Antimicrobials, Marine Sediments, Actinomycetes, Polypeptides, HPLC, UV, LC-ESI/MS, Agar Overlay, MIC, Fermentation.

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A. Lakshmana Rao , B. N. V. Ravi Kumar , G. Girija Sankar

Abstract

A simple, rapid, sensitive and precise High Performance Liquid Chromatographic (HPLC) method has been developed for the estimation of gatifloxacin in its pharmaceutical dosage forms. In this method RP - C ₁₈ column (150mmx4.6mm I.D., 5 μm particle size) with mobile phase consisting of acetonitrile and 0.05M phosphate buffer in the ratio of 25:75 v/v in isocratic mode was used. The detection wavelength is 293nm and the flow rate is 0.8ml/min. Ciprofloxacin is used as internal standard. The linearity was fo und to be in the range of 0.1 to 10 μg/ml and shows a correlation coefficient of 0.9999. The intra - and inter - day variation was found to be less than 1.2% showing high precision of the assay method. The mean percent recovery of the drug from the solution c ontaining 4 μg/ml was 100.5 ± 2.06 indicating high accuracy of the proposed method. Hence, this method is simple, fast, specific, accurate, precise and less time consuming for the estimation of gatifloxacin in pharmaceutical dosage forms.

Keywords

HPLC, Gatifloxacin, Estimation, Pharmaceutical Dosage Forms.

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