Purification and characterization of a cold active alkaline protease from Stenotrophomonas sp., isolated from Kashmir, India

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

Evaluation of hydraulic efficiency of lined irrigation channels – A case study from Punjab, Pakistan

Indus Basin Irrigation System (IBIS) in Pakistan is the backbone of agriculture in the country. The IBIS provides irrigation support to agricultural lands across the country; however, hydraulic efficiency of the water conveyance system is impacted due to seepage losses. The lining of irrigation channels is considered a potential solution for improving hydraulic efficiency. Therefore, this study explores the impact of canal lining on the hydraulic efficiency of the canals in the Punjab province of Pakistan. Overall, 14 channels/distributaries/minors (total length 226 km) were monitored in terms of hydraulic performance in different irrigation zones. Hydraulic, geometrical, and socioeconomic parameters of channel/distributaries/minors including roughness coefficient, sediments, flow velocity, wetted parameter, breaches, theft cases, bed, side slope, water surface profile, hydraulic radius, crop yield, and vegetation growth area have been experimentally observed. Obtained results have been compared with the design and pre-lining data. Ten seepage tests using the inflow -outflow method and eight seepage tests using the ponding method were conducted to estimate seepage losses. Results indicate that almost all the parameters varied from the design values. A detailed comparison of the socioeconomic parameters has been carried out. Results from seepage tests show an approximately 78% reduction in losses. HIGHLIGHTS Canal lining has reduced seepage losses by ∼78%.; Built cross-sections are ∼5% bigger than design cross-sections.; Concrete lining (1:2:4 P.C.C.) is more suitable for future canal lining.; Froma socioeconomic view, canal lining improved equity and reliability of water distribution.; The useful physical life of 1:2:4 P.C.C. lining is 30–50 years, brick lined ∼20–25 years, and protected geosynthetics more than 50 years.