Topic
Streptomyces violarus
About: Streptomyces violarus is a research topic. Over the lifetime, 2 publications have been published within this topic receiving 4 citations.
Papers
TL;DR: Bioactive metabolite producing actinomycetes were recovered from soil and tested against human pathogenic bacteria and fungi and found to have antibacterial and antifungal property.
Abstract: Background: Human pathogens are rapidly acquiring resistance to antibiotics leading to treatment failure. We carried out this study to isolate and screen actinomycetes strains that have potential to kill bacterial and fungal pathogens.Methods: In this descriptive study 288 soil and water samples were processed by standard microbiological techniques at Central Department of Microbiology, Tribhuvan University from 2013 to 2015. Screened actinomycetes were cultivated for bioactive metabolite production and minimum inhibitory concentration (MIC) of metabolites were determined against bacterial pathogens including multidrug resistant bacteria and fungi.Results: One hundred twenty isolates having antimicrobial property were screened. Out of them, four most potent strains, Nocardiopsis prasina, Streptomyces violarus, Streptomyces krainskii and Streptomyces tsusimaensis were identified all having both antibacterial and anti-fungal property.Highest zone of inhibition (ZOI)was given by N. prasina against Candida albicans(41.33 ±1.15mm) and among bacteria, maximum ZOI was against Acinetobacter baumannii(31.33±3.05mm). MIC value of metabolite of N.prasina was 0.125mg/ml for E.coli and C. albicans. It was 2.5 mg/ml each for methicillin resistant Staphylococcus aureus (MRSA), A. baumannii and Salmonella Typhi and 0.625 mg/ml for Bacillus Subtilis.Conclusions: Bioactive metabolite producing actinomycetes were recovered from soil and tested against human pathogenic bacteria and fungiand found to have antibacterial and antifungal property.
3 citations
TL;DR: Exploration of microbes isolated from rhizospheric soil of Crataegus oxycantha for bioactive natural products.
Abstract: Aim Exploration of microbes isolated from rhizospheric soil of Crataegus oxycantha for bioactive natural products. Methods and results A strain of Streptomyces sp. (C-7) was isolated from rhizospheric soil of C. oxycantha. The 16S rRNA gene sequence of strain C-7 displayed 99% sequence similarity with different Streptomyces species. The highest score was displayed for Streptomyces sp. strain Chy2-8 followed by Streptomyces violarus strain NBRC13104 and Streptomyces arenae strain ISP5293. The position of C-7 in the phylogenetic tree suggested uniqueness of the strain. Nalidixic acid (1), a quinolone antibiotic, was isolated from Streptomyces sp. strain (C-7) for the first time and characterized by NMR and chemically analysed. Compound 1 exhibited antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa. The production of compound 1 was also validated by repeating fermentation of strain C-7 and compound isolation in a separate natural product laboratory with no prior information. Furthermore, Compound 1 showed a cytotoxic effect against human prostate cancer cell line PC3 with an IC50 11 μg ml-1 . Conclusion To the best of our knowledge, this is the first report showing production of nalidixic acid naturally by a strain of Streptomyces sp. Significance and impact of the study In this study, we isolated a strain of Streptomyces sp. producing nalidixic acid, which was otherwise only obtained through chemical synthesis.
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2018 | 2 |