This study was conducted to characterize and explore the endophytic fungi of selected plants from the Western Himalayas for their bioactive potential. A total of 72 strains of endophytic fungi were isolated and characterized morphologically as well as on the basis of ITS1-5.8S-ITS2 ribosomal gene sequence acquisition and analyses. The fungi represented 27 genera of which two belonged to Basidiomycota, each representing a single isolate, while the rest of the isolates comprised of Ascomycetous fungi. Among the isolated strains, ten isolates could not be assigned to a genus as they displayed a maximum sequence similarity of 95% or less with taxonomically characterized organisms. Among the host plants, the conifers, Cedrus deodara, Pinus roxburgii and Abies pindrow harbored the most diverse fungi, belonging to 13 different genera, which represented almost half of the total genera isolated. Several extracts prepared from the fermented broth of these fungi demonstrated strong bioactivity against E. coli and S. aureus with the lowest IC50 of 18 μg/ml obtained with the extract of Trichophaea abundans inhabiting Pinus sp. In comparison, extracts from only three endophytes were significantly inhibitory to Candida albicans, an important fungal pathogen. Further, 24 endophytes inhibited three or more phytopathogens by at least 50% in co-culture, among a panel of seven test organisms. Extracts from 17 fungi possessed immuno-modulatory activities with five of them showing significant immune suppression as demonstrated by the in vitro lymphocyte proliferation assay. This study is an important step towards tapping the endophytic fungal diversity from the Western Himalayas and assessing their bioactive potential. Further studies on the selected endophytes may lead to the isolation of novel natural products for use in medicine, industry and agriculture.

Mining of soil sample from cold desert of Ladakh by functional metagenomics led to the isolation of cold-adapted endocellulase (CEL8M) that hydrolyses carboxymethyl cellulose (CMC). Mature CEL8M, a 347-residue polypeptide with a molecular mass of 38.9 kDa showed similarity to β-1,3-1,4 D-glucanase from Klebsiella sp. The enzyme contains the catalytic module of glycosyl hydrolase family 8 but does not possess a carbohydrate-binding domain. 3D structural model of the enzyme built by homology modeling showed an architecture of (α/α)6-barrel fold. The purified enzyme was found to be active against CMC, xylan, colloidal chitosan and lichenan but not active against avicel. Glucose was not among the initial hydrolysis products, indicating an endo mode of action. CEL8M displayed maximal activity at pH 4.5 and remained significantly active (~28 %) when the temperature decreased to 10 °C. Cold-active endocellulase CEL8M may find applications in textile industry at low temperature which can result in energy savings.

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A Psychrotolerant alkaline protease producing bacterium IIIM-ST045 was isolated from a soil sample collected from the Thajiwas glacier of Kashmir, India and identified as Stenotrophomonas sp. on the basis of its biochemical properties and 16S ribosomal gene sequencing. The strain could grow well within a temperature range of 4-37°C however, showed optimum growth at 15°C. The strain was found to over-produce proteases when it was grown in media containing lactose as carbon source (157.50 U mg(-1)). The maximum specific enzyme activity (398 U mg(-1)) was obtained using soya oil as nitrogen source, however, the inorganic nitrogen sources urea, ammonium chloride and ammonium sulphate showed the lowest production of 38.9, 62.2 and 57.9 U mg(-1). The enzyme was purified to 18.45 folds and the molecular weight of the partially purified protease was estimated to be ~55 kDa by SDS-PAGE analysis. The protease activity increased as the increase in enzyme concentration while as the optimum enzyme activity was found when casein (1% w/v) was used as substrate. The enzyme was highly active over a wide range of pH from 6.5 to 12.0 showing optimum activity at pH 10.0. The optimum temperature for the enzyme was 15°C. Proteolytic activity reduced gradually with higher temperatures with a decrease of 56% at 40°C. The purified enzyme was checked for the removal of protein containing tea stains using a silk cloth within a temperature range of 10-60°C. The best washing efficiency results obtained at low temperatures indicate that the enzyme may be used for cold washing purposes of delicate fabrics that otherwise are vulnerable to high temperatures.