Cellulolytic, amylolytic and xylanolytic potential of thermophilic isolates of Surajkund hot spring

A total of 41 isolates were obtained from various samples (soil, mud, and water) of Surajkund hot spring, Jharkhand, atthree different isolation temperatures of 50C, 60C, and 70C. However, our interest was in the thermophilic strains thatwere isolated at 60C and 70C. Four isolates at 70C (BITSNS038, BITSNS039, BITSNS040, BITSNS041) are theproducers of thermozymes, namely amylase, xylanase, and cellulase, respectively. The highlights of the present study alsoshowed that three out of four isolates demonstrated all three enzymatic activities, i.e. amylolytic, xylanolytic and cellulolytic on agar plate assay conditions at 70C. One of the isolates, BITSNS038, was further chosen for phenotypiccharacterization as well as 16S rRNA gene sequencing and was affiliated to Geobacillus icigianus. The presence ofGeobacillus icigianus was reported first time from hot spring, Surajkund, which showed amylolytic index of 1.58,xylanolytic index of 1.5 and cellulolytic index of 2.3 based on plate assay, and amylase activity of 0.81 U/mL, xylanaseactivity of 0.72 U/mL and very less cellulase activity of 0.15 U/mL after 24 h of growth in submerged conditions. Oneisolate at 60C BITSNS024 was found to exhibit maximum amylase activity with an enzymatic index value of 3.5 and wasidentified as Anoxybacillus gonensis.

Batch production and media optimization of anti-leukemic L-asparaginase from Pseudomonas fluorescens by Taguchi DOE methodology.

L-Asparaginase isolated from bacterial sources has been shown to possess antileukemic characteristic, mainly against the acute lymphoblastic leukemia. Large number of bacterial strains have been reported which can produce it. The production level of the enzyme by the bacterial sources is very low and hence the factors have to be distinguished which effect the growth of cells and production of enzyme directly or indirectly, in order to decrease the cost of treatment. The production of L-Asparaginase was optimized in classical fermentation process by the use of Taguchi DOE methodology. L-18 array was selected for the purpose of media optimization. The five factors at three levels were considered for the optimization. L-Asparaginase production was significantly (p<0.05) affected by the interaction of two factors present in the culture broth. The factors interaction viz. energy source-nitrogen source, energy source-phosphate source etc. having pronounced effect on the production while individually they have the minimum impact on L-Asparaginase production. So the interactions of different parameters were studied and they were used to formulate the optimized condition for the production of LAsparaginase. After the validation of result by performing the experiment under optimized condition there was about 28.48% increase in the production of the enzyme.

Influence of medium constituents on the biosynthesis of cephalosporin-C

Acremonium chrysogenum NCIM 1069 was used for the biosynthesis of cephalosporin-C (CPC) in batch mode of cultivation. The effect of different medium constituents for better yield of CPC was thoroughly investigated. From the results of the fermentation, it was found that ammonium sulphate as inorganic nitrogen source and methionine at the concentration of 0.4 percent are most suitable for higher yield of antibiotic. The variation in the C/N ratio on the biosynthesis of CPC showed that a C/N ratio of 8.0 is most suitable for maximum production of CPC