Biomaterial Database

Detection of antibiotic-producing Streptomyces inhabiting forest soils. 1978

E J Nkanga, and C Hagedorn

A modified agar overlay technique was developed for detecting antibiotic production by Streptomyces isolates and compared with two routinely used overlay procedures and the shake flask-disk assay method. Two types of inhibitory patterns could be discerned in the modified overlay method, and one of these was always exhibited by Streptomyces isolates which produced extractable antimicrobial substances. In a preliminary screening of 600 isolates, higher numbers of antibiotic-producing streptomyces were detected with the modified overlay procedure than with the streak or pour overlay method and the shake flask assay. The modified overlay distinguished between antibiotic production and other antagonistic effects. The inhibitory agents extracted after 6 days of culture growth on the modified overlay agar were of a higher concentration and more stable over longer periods of time than those recovered from shake flasks. It was observed that acidoduric streptomyces produced a greater proportion of antibiotics against gram-negative bacteria than did neutrophilic cultures, and this effect was greatest with the isolates from the most acidic soils. The neutrophiles were more active against gram-positive bacteria and, upon antibiotic classification, it appeared that the neutrophilic and acidoduric cultures from various soils produced different antimicrobial compounds.

UI	MeSH Term	Description	Entries
D008826	Microbial Sensitivity Tests	Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).	Bacterial Sensitivity Tests,Drug Sensitivity Assay, Microbial,Minimum Inhibitory Concentration,Antibacterial Susceptibility Breakpoint Determination,Antibiogram,Antimicrobial Susceptibility Breakpoint Determination,Bacterial Sensitivity Test,Breakpoint Determination, Antibacterial Susceptibility,Breakpoint Determination, Antimicrobial Susceptibility,Fungal Drug Sensitivity Tests,Fungus Drug Sensitivity Tests,Sensitivity Test, Bacterial,Sensitivity Tests, Bacterial,Test, Bacterial Sensitivity,Tests, Bacterial Sensitivity,Viral Drug Sensitivity Tests,Virus Drug Sensitivity Tests,Antibiograms,Concentration, Minimum Inhibitory,Concentrations, Minimum Inhibitory,Inhibitory Concentration, Minimum,Inhibitory Concentrations, Minimum,Microbial Sensitivity Test,Minimum Inhibitory Concentrations,Sensitivity Test, Microbial,Sensitivity Tests, Microbial,Test, Microbial Sensitivity,Tests, Microbial Sensitivity
D000900	Anti-Bacterial Agents	Substances that inhibit the growth or reproduction of BACTERIA.	Anti-Bacterial Agent,Anti-Bacterial Compound,Anti-Mycobacterial Agent,Antibacterial Agent,Antibiotics,Antimycobacterial Agent,Bacteriocidal Agent,Bacteriocide,Anti-Bacterial Compounds,Anti-Mycobacterial Agents,Antibacterial Agents,Antibiotic,Antimycobacterial Agents,Bacteriocidal Agents,Bacteriocides,Agent, Anti-Bacterial,Agent, Anti-Mycobacterial,Agent, Antibacterial,Agent, Antimycobacterial,Agent, Bacteriocidal,Agents, Anti-Bacterial,Agents, Anti-Mycobacterial,Agents, Antibacterial,Agents, Antimycobacterial,Agents, Bacteriocidal,Anti Bacterial Agent,Anti Bacterial Agents,Anti Bacterial Compound,Anti Bacterial Compounds,Anti Mycobacterial Agent,Anti Mycobacterial Agents,Compound, Anti-Bacterial,Compounds, Anti-Bacterial
D012988	Soil Microbiology	The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.	Microbiology, Soil
D013302	Streptomyces	A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.