The present study was conducted to identify and characterize the thermophilic bacteria isolated from five hot springs, viz., Sinkosh, Singha, Bhurung, Ratopani and Paudwar located in Myagdi district, Nepal by using phenotypic and genotypic methods. The hot spring has temperature 420-62 0C and pH 6.5-6.8. Isolation of thermophiles was done by using simple enriched nutrient broth media at 60 0C.Selected strains were screened for thermostable enzymes; cellulase, hemicellulase, amylase, protease, gelatinase, and lipase using substrates carboxymethyl cellulose (CMC), xylan, soluble starch, casein, gelatin and Tween (20,40,60 or 80) respectively. The bacteria were grouped in sixteen groups based on morphological and biochemical characteristics. 16S rRNA sequence analysis of sixteen isolates, one isolate representing one group and phylogenetic analysis showed the cluster of five distinct taxonomic groups. The groups were identified as for genus Anoxybacillus, Aeribacillus, Brevibacillus, Bacillus, and Geobacillus, based on ≥ 95% similarity with reference strains. This is the first study that reports Anoxybacillus sp. Brevibacillus sp. and Aeribaceillus sp. from the hot springs of Nepal.
Key words: Thermostable enzymes, amylase, cellulase, xylanase, hot springs, Anoxybacillus, Biochemical
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