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IntroductionPsychrotolerants are a more diverse group than true psychrophiles. The habitat of the latter is permanent cold regions, whereas the former can thrive in cold regions and also where mesophiles grow. The optimum and maximum growth temperatures for psychrotolerants are ≥15 °C and ≤40 °C, respectively (Morita and Moyer, 2001). Psychrotolerants can be found in deep oceans, Antarctica, the Arctic, high mountains, and man-made refrigerated systems (Russell and Cowan, 2006). There are few reports of psychrotolerant bacteria (Baghel et al., 2005;Maharana and Ray, 2013) and microfungi (Nazir et al., 2010;Maharana and Ray, 2014a) from the soil of India. The temperature of Jammu, India (32.73°N, 74.87°E) rarely reaches 37 °C and temperatures in the winter months occasionally fall below freezing.Extremozymes are seen to have immense future application in various fields of science. Enzymes from psychrotolerants are more adaptable than those from mesophiles and psychrophiles due to their wider range of temperature stability. Cold-active enzymes (CAEs) like lipase, cellulase, amylase, and protease produced from psychrotolerants are widely used in many industries, like the detergent, food, and textile industries; moreover, there is a high need for CAEs for biodegradation and bioremediation purposes in cold regions (Margesin and Schinner, 1999). Carboxymethyl cellulases (CMCase) or endoglucanases (EGs) (β-1,4-endoglucanase, EC 3.2.1.4) are inducible enzymes that are synthesized by microorganisms during their growth on cellulosic materials. In the textile industry, cold-active endoglucanases (CAEGs) can be used to remove unwanted extra fibrils from clothes so that the fabric is smoother and the clothes have increased longevity (Kumar et al., 2011). A higher temperature (60-70 °C) is needed for the saccharification of cellulose slurry and so more energy is consumed, which can be saved by the introduction of CAEGs to the slurry. Most reports of EGs were from fungi rather than bacteria and several researchers have reported on EGs produced from

Psychrotolerant yeast Rhodotorula sp. Y-23 was isolated from the sediment core sub-samples of Nella Lake, East Antarctica. Isolate was screened for lipase production using plate assay method followed by submerged fermentation. Production optimization revealed the maximum lipase production by using palmolein oil (5% v/v), pH 8.0 and inoculum size of 2.5% v/v at 15 °C. The potential inducers for lipase were 1% w/v of galactose and KNO , and MnCl (0.1% w/v). Final productions with optimized conditions gave 5.47-fold increase in lipase production. Dialyzed product gave a purification fold of 5.63 with specific activity of 26.83 U mg and 15.67% yields. This lipase was more stable at pH 5.0 and -20 °C whereas more activity was found at pH 8.0 and 35 °C. Stability was more in 50 mM Fe , EDTA-Na (20 mM), sodium deoxycholate (20 mM), H O (1% v/v), and almost all organic solvents (50% v/v). Tolerance capacity at wider range of pH and temperature with having lower K value i.e., 0.08 mg ml and higher V 385.68 U mg at 15 °C make the studied lipase useful for industrial applications. Besides this, the lipase was compatible with commercially available detergents, and its addition to them increases lipid degradation performances making it a potential candidate in detergent formulation.

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A psychrotolerant yeast strain Mrakia robertii A2‐3 isolated from cryoconites of Hamtah glacier, Himalaya, India was investigated for the production of cold‐tolerant endoglucanase. Optimum endoglucanase production was found at 15°C with an initial pH of 5.5, and potent inducers were 1% wt/vol of xylose and KNO3 and 0.1% wt/vol of NaCl. Under optimum conditions, the enzyme production was 1.81‐fold higher than the unoptimized conditions. Crude enzyme was partially purified by ammonium sulfate precipitation followed by dialysis. The enzyme was purified to 2.53‐fold and the yield was 6.03% with specific activity of 17.38 U/mg and molecular weight ~57 kDa. The Km and Vmax values of the partially purified enzyme were found to be 1.57 mg/ml and 142.85 U/mg, respectively. The characterization study revealed that the best temperature was 15°C for activity and stability. Furthermore, the enzyme showed the highest activity at pH 11.0 and was stable at pH 6.0. Fe2+, Mn2+, Na2+, Cu2+, Co2+, Ca2+ proved to be activators of endoglucanase. Ethylenediamine tetraacetic acid showed very low effect on the enzyme activity whereas it was active with Tween‐80 and sodium deoxycholate. The present study successfully produced a cold‐active endoglucanase with novel properties making it promising as a biocatalyst for industrial processes.

Objective:The objective of the present study was on Penicillium pinophilum strain F2 from soil samples of Jammu city having the potentiality to produce alkaline cold active endoglucanase and pigment.Methods: Penicillium pinophilum strain F2, a psychrotolerant micro-fungus was isolated from soil of Jammu city, India by taking Czapek's Dox agar incubated at 15 °C. The strain was screened for production of cold active enzymes by taking various substrates at 15 °C. Final production was done for cold active endoglucanase by using sugarcane bagasse and ground nut shell as substrates. Besides, the strain was also able to produce red color pigment at a low temperature which was further studied to optimize its production by changing pH and growth medium. The produced pigment was used for dyeing of wool and silk, and absorption percentages were also calculated. Results:Screening for the production of cold active enzymes revealed it as a good producer of cellulose followed by lipase and amylase. Endoglucanase production revealed the total enzyme titer (total enzyme activity) was found to be 5.032 folds higher in sugarcane bagasse (38.91 units) than groundnut shell (7.732 units). Endoglucanase activity was maximum 9.82±0.33 units/ml and 2.29±0.31 units/ml after 120 h of incubation at 15 °C by sugarcane bagasse and groundnut shells, respectively. Red color pigment production was maxima at pH 5 in Czapek's Dox broth. Maximum absorption percentage was seen by the treatment soaked with mordant, i.e. 5% CuSO4 (51.52%) and without a mordant, it showed about 45.54%.Conclusion: Due to the above unique features and capability to produce cold active endoglucanase and pigment by strain F2, can be used significantly in various industries.

Proteases are the hydrolytic enzymes that act up on different kinds of proteins lead to formation of smaller peptides and amino acids. On the basis of action it is of exo-or endo-peptidase and it is of four types on the basis of functional groups viz. serine-, cystein-, aspartic-and metallo-protease. The protease types depend on the composition of the production medium; therefore, one microorganism can produce various types of