Hyperthermostable alkaline lipase from Bacillus sonorensis 4R was purified and characterized. The enzyme production was carried out at 80°C and 9.0 pH in glucose-tween inorganic salt broth under static conditions for 96 h. Lipase was purified by anion exchange chromatography by 12.15 fold with a yield of 1.98%. The molecular weight of lipase was found to be 21.87 KDa by SDS-PAGE. The enzyme activity was optimal at 80°C with t 1/2 of 150 min and at 90°C, 100°C, 110°C, and 120°C; the respective values were 121.59 min, 90.01 min, 70.01 min, and 50 min. The enzyme was highly activated by Mg and t 1/2 values at 80°C were increased from 150 min to 180 min when magnesium and mannitol were added in combination. The activation energy calculated from Arrhenius plot was 31.102 KJ/mol. At 80–120°C, values of ΔH and ΔG were in the range of 28.16–27.83 KJ/mol and 102.79 KJ/mol to 111.66 KJ/mol, respectively. Lipase activity was highest at 9.0 pH and stable for 2 hours at this pH at 80°C. Pretreatment of lipase with MgSO4 and CaSO4 stimulated enzyme activity by 249.94% and 30.2%, respectively. The enzyme activity was greatly reduced by CoCl2, CdCl2, HgCl2, CuCl2, Pb(NO3)2, PMSF, orlistat, oleic acid, iodine, EDTA, and urea.

Microbial lipases catalyzing the hydrolysis and synthesis of esters from glycerol and fatty acids are commercially important in food, dairy, detergent and leather industries. In the present study, 15 thermo-alkalophilic bacterial strains isolated from a compost soil sample were screened for lipase production in beef extract nitrate medium containing 1% tributyrin. The strain 8C, giving maximum lipolytic activity was morphologically and biochemically identified as Bacillus sp. Lipase production from strain 8C was optimized by studying effects of incubation period, initial pH of medium, carbon and nitrogen sources, metals, substrates and thiols under static conditions. Lipase production was maximum after 7 days of incubation at 50°C and pH 9.0 and when sesame oil was used as a substrate. Supplementation of ribose or raffinose and ammonium sulphate (1%) as sole sources of carbon and nitrogen also stimulated lipase production over control. Of the different thiols tested, methionine greatly increased lipase production (175 Eu mLG 1 ) whereas, FeCl 3 (50 mM) found to be most suitable metal salt for optimal lipase production (300 Eu mLG 1 ). Under optimized conditions, lipase production by thermo-alkalophilic Bacillus sp. 8C was increased by 6.36 fold compared to unoptimized conditions. Key words: Thermophilic, alkaline, ribose, FeCl 3 , methionine, sesame oil INTRODUCTIONLipases (triglycerol hydrolases (EC 3.1.1.3) are the hydrolytic enzymes belonging to serine hydrolase family and catalyze conversion and synthesis of esters from glycerol and fatty acids. Lipolytic reactions are highly chemo-, regio and or enantioselective and operate at the interface of oil and water (Nguyen et al., 2010). High quality and low energy consumption of lipase catalyzed reactions make them superior over conventional steam splitting methods operating at high temperature and pressure (Treichel et al., 2010). These characteristics of lipases increased their demand in different industries including food and dairy, detergent, cosmetics, leather, paper and pulp, biodiesel and pharmaceutical (Hasan et al., 2007).Thermophilic lipases are of special interest for industrial applications due to their stability and high activity at higher temperatures and being stable in presence of chemicals (Messias et al., 2009;Uttatree et al., 2010). Lipases being third largest selling group of enzymes with more than 1000 t of annual production and approaching to a billion dollar business. Lipases active at alkaline pH are of great importance in detergent industry where these enzymes are used for removal of fat stains and dirt (Bora and Bora, 2012). The use of alkaline lipases in detergent formulation substantially

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Background: Pardosa is the genus of wolf spiders erected by C. L. Koch, 1847, currently represented by 549 species worldwide and 40 species from India.

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Endophytes considered as a potent source of naturally produced bioactive compounds. This study was designed to isolate fungal endophytes that are capable of producing Glutaminase free L-asparaginase enzyme from the selected medicinal plants of Nanded city, Maharashtra, India. Four host medicinal plants traditionally known to have antitumour properties, i.e., Curcuma longa, Murraya koenigii, catharanthus roseus and Withania somnifera were selected for this study. Among the total seventy eight (78) isolated fungal endophytes, only five isolates were shown Glutaminase free L-asparaginase production activity. Fusarium solani isolated from Curcuma longa showed the highest enzyme production activity level as compared to others by 619.102 IU ml -1 with 8.807 IU mg -1 specific activity, followed by F.oxysporum (514.532 IU ml -1 with 7.401 IU mg -1 specefic activity), Penicillium sp. (307.114 IU ml -1 with 5.033 IU mg -1 specific activity ), Aspergillus sp. (216.847 IU ml -1 with 4.920 specific activity ) and Alternaria sp. (149.057 IU ml -1 with 3.035 IU mg -1 specific activity). This study demonstrate the importance of using fungal endophytes from antitumour plant hosts as a good and potent alternative source for L-asparaginase production with novel characteristics at high therapeutic index.

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