Identification and Characterization of Antibiotic-Producing Actinomycetes Isolates

Abstract

Actinomycetes are a gram-positive, filamentous subgroup of bacteria most known for antibiotic production. In fact, most of the antibiotics available today have originated from actinomycetes, namely from the genus Streptomyces. Novel bacteria with antimicrobial activities have been discovered from bacterial screen studies for decades and there is still much more yet to be unearthed. One hundred seventy five strains of actinomycetes were isolated from 38 different soil samples from different locations in Patna, India. Potential antibiotic producers were screened against four test microorganisms (Escherichia coli MTCC 739, Staphylococcus aureus MTCC 96, Streptomyces lividans TK23 MTCC 4 and Candida albicans MTCC 227). The bioassay revealed that about 26% of actinomycetes isolates were active against at least one of the test microorganism. Characterization of a selected isolate has led to identification of a unique strain of actinomycetes (MP 525) showing broad-spectrum antibacterial and antifungal properties. The strain MP 525 has been morphologically characterized as Streptomyces sp. and deposited at MTCC, Chandigarh, India with accession number 8723. The 16S rRNA gene of the strain Streptomyces sp. US7 MTCC 8723 was sequenced and the DNA sequence was deposited at NCBI, Bethesda (GenBank accession. No. HQ659005). On the basis of λmax values of culture filtrates, it has been suggested that the strain might be producing LL-E19085-like antibacterial and a flavone glycoside-like antifungal antibiotics, which can be further exploited for industrial and biological applications.

Production of Antimicrobial and Anticancer Fom Feather-Keratinolytic Nocardiopsis Sp. 28ror as a Novel Strain Using Feather Meal Medium

“…The best one (P˂ 0.05) was selected to produce antimicrobial substances (the isolate 28 ROR). These results in consensus with previous studies that documented the actinobacterial species are the main sources for producing antimicrobial substances and the same organisms had the ability to produce antifungal, antibacterial and anticancer substances [2,3,[20][21][22][23][24].…”

Optimization of various physiochemical parameters to enhance production of secondary metabolite from soil actinomycetes against dermatophytes

“…The effect of different pH 3,4,5,6,7,8 and 9 and temperature 25,28,30,35,40,45 and 50°C. Different minerals such as MgCl 2 CuSO 4 , MnSO 4 , FeSO 4 , CoCl 2 , ZnCl 2 and KNO 3 and their concentration (0.001-0.25 mg/ml) and the incubation time were also optimized from 1 to 15 days (Majumdar et al, 1965;Jyotsnamayee and Gupta, 2010;Kumar et al, 2012;Kumari et al, 2013;Shukla et al, 2014;Parmar et al, 2010). The young broth culture of selected isolates were inculcated into the broth medium and incubated in the orbital shaker at 130 rpm, 30º C for 7 days.…”

“…It was found during the optimization of isolate AP-27 that among various carbon and nitrogen sources starch and potassium nitrate selected as best carbon and nitrogen sources for secondary metabolite production and cell growth. Kumari et al (2013), optimized the nutritional condition by using 8 different media for antibiotic production by Streptomyces sp. and starch casein broth was selected as best medium.…”

“…Media composition influence the economics of product and process (Mangamuri et al, 2016). Actinomycetes are economically and biotechnologically important and it is also responsible for production of secondary metabolite like antibiotics, anticancer agent and enzymes (Kumari et al, 2013). Production of secondary metabolite by fermentation influenced by many factors as fermentation time, ventilation, temperature, initial pH combination of media components, minerals and culture conditions.…”

A Biophysiochemical Analysis of Settled Livestock and Poultry Housing Dusts

“…Evaluation of the 16S ribosomal DNA gene, the genomic sequence that encodes the 16S portion of Science Publications AJABS prokaryotic ribosomes and is thus present in all bacterial species, is an established approach for detection and identification of bacterial species (Ege et al, 2012;Kumari et al, 2013). For bacterial detection and identification, DNA was isolated from dust samples (0.1-0.5 g) using the Power Soil DNA isolation kit (Mo Bio, Carlsbad, CA) according to manufacturer instructions.…”