Isolation and Characterization of Antibacterial Actinomycetes from Soil Samples of Kalapatthar, Mount Everest Region

Abstract

Seventy-nine Actinomycetes were isolated from soils of Kalapatthar (5545m), Mount Everest region. Twenty seven (34.18%) of the isolates showed an antibacterial activity against at least one test-bacteria among two Gram positive and nine Gram negative bacteria in primary screening by perpendicular streak method. Thirteen (48.15%) showed antibacterial activity in secondary screening. The result showed that three of the isolates, K.6.3, K.14.2, and K.58.5 were highly active with an inhibition zone e"20mm and broad spectrum antibacterial activity including two methicillin resistant Staphylococcus aureus (MRSA) strains. Minimum inhibitory concentration (MIC) of antibacterial metabolites of the isolate K.6.3 was 1mg/ml, and that of isolates K.14.2 and K.58.5 was 2mg/ml. Two spots were detected on thin layer chromatography plate from each of the metabolites which was completely different from the spot produced by vancomycin. The active isolates from primary screening were heterogeneous in their overall macroscopic, biochemical, and physiological characteristics through unweighted pair group method using average (UPGMA) cluster analysis. Delineation of the three active isolates showing potent broad spectrum antibacterial activity revealed that they belonged to distinct taxonomic groups.

Isolation and characterization of potential antibiotic producing actinomycetes from water and sediments of Lake Tana, Ethiopia

“…The inhibition zones of crude extracts from LT001 and LT002 were at the maximum of 12 mm and 10 mm respectively against E. coli and the results were statistically significant (df 2, 6; F=285.36; P=1.13E-06) ( Table 4). The extracts of LT003, LT007 and LT009 showed statistically significant results against P. aeruginosa (df 3, 8; F=27.53; P=0.000 14).…”

“…Species of Streptomyces, account for more than 70% of the total antibiotic production and Micromonospora was less than one-tenth as many as Streptomyces [13] . Twenty seven actinomycetes were isolated from Mount Everest region soil samples and reported to have antibacterial activity against at least one tested bacteria among the two Gram positive and nine Gram negative bacteria [14] . Narendra Kumar et al isolated 117 antibiotic producing actinomycetes from non agricultural wasteland alkaline soils and compost rich garden soil in which most of the isolates inhibits Gram negative bacterial growth [15] .…”

Isolation and screening of antibiotic producing actinomycetes from soils in Gondar town, North West Ethiopia

“…Agar and pairing studies. They are characterized by having a high G+C content (>55%) in their DNA [4][5][6] . Actinomycetes are of universal occurrence in nature and are widely distributed in natural and man-made environments.…”

Antimicrobial Potential of Actinomycetes Isolated from Soil Samples of Punjab, India

“…This shows that the antimicrobial compound produced is a very effective compound. Low MIC value has been reported for isolate K.6.3 as 1mg/ml, and that of K.14.2 and K.58.5 as 2mg/ml against S. aureus ATCC 29213 [12]. The MICs of the ethyl-acetate extract of Streptomyces (TR 007) ranged from 0.15 to 5 mg/ml and that for Actinopolyspora (TR 008) varied between 0.039 and5 mg/ml when tested against different Gram positive and Gram negative bacteria [13].…”

“…inhibitor to both Gram positive and Gram negative bacteria [12]. In the present study, isolate A5 was obtained by ethyl-acetate extraction and the MIC against two different bacteria Klebsiella pneumonia and Salmonella typhi was 0.012 mg/ml.…”