Antibiotic potential of actinomycetes from different environments against human pathogens and microorganisms of industrial importance: a review (original) (raw)
Related papers
2011
Actinomycetes are group of bacteria, which are present widely in ecological diversity. Actinomycetes are the major microbial population in soil which can produce active secondary metabolites. Aim of this study is to isolate varieties of Actinomycetes from different locations to evaluate its antimicrobial activity. Soil samples were collected from different niche habitats of Gwalior (Dry soil from Hostel zone of Madhav Institute of Technology and Science (MITS), Cancer hospital territory, IIITM ground, forest areas of Sanjeevani nursery) and used for actinomycetes isolation. The seven actinomycetes isolates were isolated from different soil samples based on their colony morphology, mycelium colouration and diffusion of pigmentation. The isolates were analysed for their biochemical activity and found that all the isolates were positively active for catalase, starch and casein utilization. The isolates were screened for their secondary metabolites activity on three human pathogenic bacteria are Escherichia coli, Staphylococcus epidermis and Vencomycin resistant Enterococci (vre). The isolate 5 was found to be more active against the test bacteria. The isolate 5 was further tested for its zone of inhibition and found maximum activity (14 mm) against the test bacteria. It was concluded that actinomycetes isolate 5 had potentials as sources of new antibacterial compounds against pathogenic microorganisms (unicellular Gram positive and Gram negative bacteria and drug resistance microorganism) to humans.
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.
Actinomycetes: a yet inexhaustive source of bioactive secondary metabolites
2013
The rapid emergence of antimicrobial resistance among pathogens has led to a renewed interest to search for novel antimicrobial agents. The history of new drug discovery processes shows that novel skeletons have, in the majority of cases come from natural sources. This involves screening of microorganisms or plant extracts. They have been the source of, or inspiration for the development of chemical entities introduced as pharmaceutical. Among microorganisms, actinomycetes are enthralling resource due to their ability to produce novel bioactive secondary metabolites with antimicrobial activities. They have proven to be an inexhaustive mine of antimicrobial agents, especially those potent against pathogenic organisms. Microbial secondary metabolites, especially those from actinomycetes have been a phenomenal success for the discovery of novel drugs. They produce a wide range of secondary metabolites and more than 70% of the naturally derived antibiotics are currently in clinical use. They remain a fundamental source of new chemical diversity and an important part of drug discovery. Their ingenuity and immense industrial value is extremely noteworthy. The discovery of Streptomycin from actinomycetes has been imperative to the exploration of this group as a source of novel bioactive compounds. This group of organisms have produce antibiotics in different classes such as aminoglycosides, ansamycins, anthracyclines, glycopeptides, β-lactams, macrolides, nucleosides, peptides, polyenes, polyethers, and tetracyclines. Existence of actinomycetes has been reported in both terrestrial and marine habitats. This chapter highlight the bioactive metabolites produces by actinomycetes and their mode of action.
Uttarakhand region is less explored, but possess a great biodiversity. This diversity can be explored for isolation and characterization of new actinomycetes strains for seeking antimicrobial molecules. It can therefore be predicted that novel bioactive metabolite producing actinomycetes can be discovered to combat multidrug resistant bacterial pathogens. Materials and Methods: Variations in the viable count of actinomycetes were accessed in different altitudes. Actinomycetes were isolated, indentified and screened for their antibacterial activity. Results: The highest viable counts of actinomycetes were recorded in valleys followed by mid hills and high hills. A total of 512 actinomycetes were isolated which were found to belong the 14 different genera of actinomycetes. Mainly the genus Streptomyces was dominant in all the soil samples. Out of 512 isolates recovered, 23.44% exhibited antibacterial activity against one or more tested bacterial pathogens. Of these 56.67% showed activity against Gram-positive bacteria, 26.67% against Gram-negative bacteria while 16.67% showed broad spectrum activity. Isolate DV1S and GR9a-5 showed highest antibacterial properties against several multi-drug resistant bacterial pathogens and were identified using polyphasic approach. DV1S and GR9a-5 were found to be most closely related with S. massasporeus NBRC 12796 T and Nocardia nova JCM 6044 T respectively.
Isolation and screening of antibiotic producing actinomycetes from soilsinManong, Perak, Malaysia
Der Pharmacia Lettre, 2016
The present study focuses on isolation of actinomycetes from the soil in Ulu Kenas forests of Manong, located in the northern part of Perak state in Malaysia and screening for antibacterial activity. All the isolates were screened for their antibacterial activity using Kirby-Bauer (KB) method against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pnemoniae and Staphylococcus aureus. Out of the ten isolated actinomycetes, seven, namely B, D, E, F, H, I and J showed antimicrobial activity against selected bacteria. However, isolates E showed maximum inhibition against P. aeruginosa and the isolates I and J against K. pneumonia with highest scores. The findings of the study may be helpful to the future investigators in identifying alternative and new bioactive secondary metabolites like antibiotics to treat resistant human pathogens.
Reappraisal of actinomycetes for novel bioactive metabolites
Annals of Phytomedicine: An International Journal, 2017
The appearance of new deadly diseases like cancer and the burgeoning problem of drug resistance among common bacteria l pathogens are a serious threat to a vailable trea tments. Since the channels of compounds under development are limited, this necessitates the discovery of new drugs. It is where actinomycetes can complement in the accomplishment of development of thera peu tically new bioactive compounds, predomina ntly u sed in antibiotic production. Actinomycetes are diverse in their location and have proven ability to produce new bioactive compounds. By employing modern microbiological and molecular technologies, the target-directed search for detection and isolation of bioactive actinomycetes is gaining more strength. Therefore, the innova tive isolation of actinomycetes from extreme ecosystems, their identification and cultivation using novel techniques are imperative to pursue for drug discovery.
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.
“ Search for Antimicrobial Agents Produced by the Soil Actinomycetes ”
2014
Actinomycetes are biotechnologically important bacteria which are well exploited for secondary metabolites. Screening, isolation and characterization of capable strains of actinomycetes producing potential secondary metabolites has been a most important area of research by many groups worldwide for many years. Actinomycetes are the foundation of the antibiotics industry and hold a significant role in producing variety of drugs that are extremely vital to our health and nutrition. Research has been demonstrate that a large number of antimicrobial agents have been produced from the soil. One of the first antibiotics used is streptomycin produced by Streptomyces griseus. Among Actinomycetes, approximately 7600 compounds are produced by Streptomyces species. The actinomycetes are a group of grampositive bacteria that exhibit characteristics of both bacteria and fungi. The genus Streptomyces is responsible of the synthesis of the majority of antimicrobial agents with clinical importance ...