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Lower Shiwalik foothill ranges (Kandi regions) are dominated by different land use systems, varying in fertility status due to soil erosion owing to undulating topographical features. For assessment of soil nutrient status of study area, the soil sampling was conducted to investigate the variation in micronutrient status and physicochemical characteristics of soil. Long-range basis soil sampling was carried out in 11 blocks falling in the entire Shiwalik ranges of lower Himalaya under different land use systems (LUSs), viz., agriculture (AG), horticulture (HR), agri-horticulture (AH), grassland (GL), and agroforestry (AF) systems. A total of 440 soil samples were collected from two depths (0–15, 15–30 cm) for analysis. The results had reported that the soils were slightly acidic to slightly alkaline (6.61 to 8.10) in the whole range. Soil organic carbon (SOC) was found to be varying from very low to very high (2.43 to 10.43 g kg−1). DTPA-extractable Fe and Mn were found to be in dominant concentrations in the soils whereas, the deficiency of Zn was found under all existing land uses. Interestingly, Fe (r = 0.62*), Cu (r = 0.44), and Mn (r = 0.35) micronutrients were positively correlated with clay content whereas Zn (r = − 0.02) was negatively correlated. Soil quality based on principal component analysis (SQI-PCA) reported clay, SOC, and Zn are major dominating parameters to be considered of soil in Shiwalik ranges. [ABSTRACT FROM AUTHOR]

The aim of present study was to analyze the prevalence of protease diversity among psychrotrophic bacteria in Lahaul and Spiti of the Western Himalayas. A total of 459 bacteria were screened and protease activity was observed in 150 isolates at 5 °C. Furthermore, 55 isolates showed protease activity up to pH 10 at 5 °C. Based on the hydrolytic zone, 22 isolates were selected for protease quantification. The protease activity varied from 58–377 U mL−1 at 10 °C, 49–396 U mL−1 at 28 °C and 31–407 U mL−1 at 37 °C. Similarly, protease activity ranged from 36–353 U mL−1 at pH 7, 40–306 U mL−1 at pH 9 and 33–304 U mL−1 at pH 10. The isolates were identified based on 16S rRNA gene sequencing and showed phylogenetic relationship to Arthrobacter belonging to the class Actinobacteria, Bacillus, Exiguobacterium, Paenibacillus, and Planomicrobium to Bacilli, and Pseudomonas, Serratia, and Stenotrophomonas to Gammaproteobacteria. Zymogram analysis revealed variations in protease isoforms ranging from 20 to 250 kDa which were strongly inhibited in the presence of phenylmethylsulfonyl fluoride, thus indicated serine-type nature. The extensive number of serine proteases among these bacteria was confirmed by annotating genomes of the reported genera for prevalence of protease isoforms. The properties of proteases including low-temperature activity with alkaline stability and detergent compatibility suggested their suitability as bio-additives in laundry. [ABSTRACT FROM AUTHOR]

Microbial proteases are explored for their role in food, detergent, bioremediation, pharmaceuticals, silk degumming and leather processing. Here, Acinetobacter sp. IHB B 5011 previously isolated from Western Himalayas was explored for optimization of protease production. A total of seven culture media; Basic medium (BM), Nutrient broth (NB), Gelatin broth (GB), Tryptone dextrose broth (TDB), Peptone Dextrose Broth (PDB), and Glucose Yeast extract Broth (GYB) were used. The maximum protease activity was recorded in PDB medium after 36 h. Different parameters including carbon and nitrogen source, inoculum and CaCl 2 were evaluated based on Plackett-Burman design for optimum yield. The response for protease activity varied from 215-436 μg min-1 ml-1. Further, optimization based on Central Composite Design revealed protease production with 1.4 g dextrose, 0.7 g tryptone and 0.7 g yeast extract per 50 ml medium. A significant increase in protease activity was monitored from 323 μg min-1 ml-1 to 562 μg min-1 ml-1 after optimization. [ABSTRACT FROM AUTHOR]