Potentials of Actinomycetes from Reserved Environments as Antibacterial Agents Against Drug-Resistant Clinical Bacterial Strains (original) (raw)
Related papers
Dynamism of Antimicrobial Activity of Actinomycetes—A Case Study from Undisturbed Microbial Niche
Advances in Microbiology, 2014
Escalation of drug resistant microbes (bacteria) had forced researchers to search new and improved therapeutic compounds from different possible sources, including metabolites secreted by the actinomycetes. The aim of this study was to evaluate the pattern of antimicrobial actinomycetes from physiologically distinct soil of different geographical locations. Forty five soil samples were collected from 5 districts of Gujarat including two sanctuaries as source of survey for bioactive actinomycetes. Crowded plate technique was used for isolation and Agar cylinder method was employed for the antimicrobial screening. A total of 171 actinomycetes were isolated and screened against eighteen pathogens responsible for causing diseases in plants and humans. Results indicate that 79% of the isolates were active against at least one of the eighteen tested pathogens. Some of the actinomycetes strain had shown strong antibacterial and antifungal activity which may be a good source of obtaining novel antimicrobials.
Screening of Actinomycetes from Soil for Antibacterial Activity
2020
Actinomycetes are Gram positive, free living saprophytes which are distributed in soil as one of the major populations and are primary source of antibiotics. This study was carried out with a quest to isolate actinomycetes from soil samples of different places and assess their antibacterial activity. Isolation of actinomycetes was carried out by serial dilution of soil sample followed by spread plate method. The antimicrobial extract was extracted using ethyl acetate. Assessment of antimicrobial activity was performed by using Agar cup plate assay against test organisms (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Salmonella paratyphi, Bacillus subtilis, Staphylococcus aureus). Antibacterial activity was tested against Methicillin Sensitive Staphylococcus aureus and Methicillin Resistant Staphylococcus aureus in the isolates having effective inhibitory activity against Staphylococcus aureus. From 15 soil samples of 12 different locations, 121 a...
2011
Purpose: The rapid emergence of drug resistance among pathogenic bacteria, especially multidrug-resistant bacteria, underlines the need to look for new antibiotics. Methods: In the present study, 134 different actinomycetes, isolated from the soil samples collected from different localities of Punjab and Himachal Pradesh, were screened for antimicrobial activity against various test organisms including multidrug-resistant methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli in order to identify potential antibiotic producers. Results: Among these isolates, 51 (38 %) showed antimicrobial activity against one or more test organisms and six exhibited promising broad-spectrum activity against all the tested organisms. The observed cultural, morphological, physiological and biochemical characteristics confirmed that these isolates are species of the genus, Streptomyces. Conclusion: Further studies on the bioactive metabolites from these cultures will be useful for disc...
Isolation and screening of soil Actinomycetes as source of antibiotics active against bacteria
Inter. J. Microbiol. …, 2010
A total of 117 actinomycetes strains were isolated from the wasteland alkaline and garden soil samples of the Ghaziabad and screened for their anti-bacterial activity. They were evaluated for their inhibitory activities on four test microorganisms. Fifteen actinomycetes isolate which exhibited antimicrobial activity against at least two of the test organisms and were characterized by conventional methods. The cultural characteristics of isolates were also studies in different culture media. The results indicated that six isolates were highly active against Staphylococcus aureus strains. Seven isolates were highly active with an inhibition zone more than 20 mm in diameter. Most of the isolates inhibited growth of the Gram negative bacteria tested. All the antibiotic producing actinomycetes were isolated at different temperatures from non agricultural wasteland alkaline soil and compost rich garden soil. Fifteen isolates showed activity against bacteria in which most of them from wasteland alkaline soil where the less interference by human for agriculture or other purpose. These microorganisms may have capability to produce some of the most important medicines ever developed.
Isolation of actinomycetes with antibacterial activity against multi-drug resistant bacteria
Malaysian Journal of Microbiology
Aims: To isolate and characterise actinomycetes from various sources of soil samples (fruit orchard, dipterocarp forest and oil palm plantation) and to screen these isolates for antibacterial activity against multi-drug resistant bacteria. Methodology and results: A total of 158 fast-growing actinomycete isolates with different colony morphology were subjected to primary cross-streak and secondary well diffusion screening. Six isolates (OP1E, OP7A, OP2A-C, MG1A, UT9C1 and UT7E) were found to inhibit at least one of the seven multi-drug resistant (MDR) bacteria. MG1A exhibited the strongest and broadest spectrum of antibacterial activity against 6 MDR bacteria tested. These isolates were identified as Streptomyces species based on 16S rRNA gene sequence analysis. Further morphological and biochemical analysis revealed that MG1A was highly similar to S. griseocarneus (98.36%) whereas OP1E and OP2A-C were similar to S. parvulus (99.93% and 99.51% respectively). Preliminary identification using LCMS/MS and database search revealed that the major compound in the extract of OP2A-C could be dactinomycin (1255.4170 g/mol). Other antibacterial compounds in the extracts remain to be identified. Conclusion, significance and impact of study: Soil actinomycetes with antibacterial activity against MDR bacteria were isolated not only from undisturbed natural soils but cultivated soils. These isolates were characterised, identified and the antibacterial compounds were extracted for further study. The isolates could serve as a potential source for the development of new and sustainable compounds against MDR bacteria.
2020
Actinomycetes are Gram-positive, aerobic and thread like bacteria with high DNA G+C contents. They are free-living, saprophytic, and abundant in soil, water, and colonizing nodulating plants. Actinomycetes assume a significant job in reusing squanders in the earth and they are additionally the makers of thousands of metabolic items, which display organic action. Due to the outstanding history of actinomycetes in the production of bioactive molecules for human interest, a large number of efforts have been made on the isolation, characterization and identification from terrestrial sources in the past half-decade. Secondary metabolites obtained from various potential strains of actinomycetes are very effective against Gram-positive and Gram-negative bacteria. Many researchers both nationally and internationally isolated this potential group of microorganisms from soil, water, sediment etc. and checked their potential antimicrobial activity. In the present review, antibiotic potential o...
2019
Due to acquired resistance produced by micro-organism against all frequently used antimicrobial agents, there is a great need of newer antibiotics to fight against different microbes. To explore the unknown diversity of microorganisms, soil screening for antimicrobial agents are performed for the detection of newer antibiotics from Actinomycetes. Studies were carried out with isolation of total 65 actinomycetes from rhizospheric soil of plants. Isolation and characterization of antimicrobial agents producing actinomycetes was performed and after screening some of isolates were having antimicrobial activity. Among them isolate AIA29 from rhizospheric soil was further studied for their potential. In the present study soil samples have been collected from different regions of Rajasthan. Isolation of actinomycetes was done on Actinomycetes Isolation Agar (AIA) media. Gram staining, characterization of colony and extraction of bioactive compounds was done by solvent extraction method. An...
Tropical Journal of Pharmaceutical Research, 2010
Purpose: To investigate the production of antibiotic from actinomycetes isolated from soil and evaluate its antimicrobial activities. Methods: In a medium formulation study, A-4 and A-4 actinomycete mutant strains (out of the six strains selected from the nine actinomycetes that were screened) were evaluated for maximum antibiotic production using various carbon and nitrogen sources. Zone of inhibition and packed cell volume were the parameters used for the evaluation. Various fermentation conditions such as pH, temperature and dissolved oxygen were also optimized for maximal production of antibiotic from both A-4 and A-4 mutant. Results: Some actinomycetes strains showed promising antimicrobial activity against different strains of bacteria and fungi. Out of the six strains selected, one strain, designated A-4, showed maximum antimicrobial property against Gram positive and Gram negative strains as well as against various fungi. Conclusion: Findings from this investigation reveal that strain A-4 and A-4 mutant strains, in that order, exhibited superior antimicrobial activities to other soil isolates of actinomycetes.