scispace - formally typeset
Search or ask a question
Author

Sanjeev Kumar

Bio: Sanjeev Kumar is an academic researcher from VIT University. The author has contributed to research in topics: Harmonic & Power (physics). The author has an hindex of 2, co-authored 4 publications receiving 23 citations.

Papers
More filters
Journal ArticleDOI
TL;DR: The current study demonstrated the enhanced production of NK by P. aeruginosa CMSS UV60 by media optimization and strain improvement, which is the first report on the production ofNK from P.aerugin Rosa CMSS.
Abstract: strain improvement. Materials and Methods: In the present study, a potent NK-producing strain was isolated from cow milk and identified. To enhance the yield of NK, effect of various parameters such as pH, temperature, carbon source, nitrogen source and inoculum size were optimized. Strain improvement of P. aeruginosa CMSS was done by random UV-mutagenesis. Nattokinase was partially purified and the activity was determined by the casein digestion method, blood clot lysis and fibrin degradation assay. Results: Based on morphological, biochemical and molecular characterization, the strain was confirmed as P. aeruginosa (GenBank accession number: JX112657), designated as P. aeruginosa CMSS. The optimum condition at pH 7 and temperature at 25˚C showed activity of NK as 1514 U mL -1 and 1532 U mL -1 , respectively. Sucrose as the carbon source and shrimp shell powder (SSP) as the nitrogen source expressed NK activity of 1721 U mL -1 and 2524 U mL -1 , respectively. At 1% inoculum size, the maximum rate of enzyme production was achieved with 2581 U mL -1 . The NK activity of the mutant strain UV60 was 4263 U mL -1 , indicating a two-fold increase in activity compared to the wild strain (2581 UmL -1 ). Nattokinase produced from mutant strain P. aeruginosa CMSS UV60 showed 94% blood clot lysis at ten minutes. The degradation of fibrin clot by the produced NK was observed after two hours of incubation. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) confirmed the molecular mass of CMSS UV60 NK to be 21kDa. Conclusions: The current study demonstrated the enhanced production of NK by P. aeruginosa CMSS. This study is unique and the findings are the first report on the production of NK from P. aeruginosa CMSS isolated from cow milk.

25 citations

Journal ArticleDOI
TL;DR: A new feather-degrading bacterium was isolated from soil near poultry waste and identified as Bacillus cereus VITSDVM4 (Accession number KJ725087).
Abstract: A new feather-degrading bacterium was isolated from soil near poultry waste. Based on the morphological, physiochemical, and phylogenetic characteristics, the keratinolytic bacteria was identified as Bacillus cereus VITSDVM4 (Accession number KJ725087).To enhance the yield of keratinase, the effect of various parameters such as pH, temperature, carbon source, nitrogen source, substrate concentration, inoculum size and incubation time were optimized. The maximum keratinase activity was found to be 134 U ml−1 at pH 7. At 25 °C, it was slightly increased and showed 174 U ml−1 activity. The carbon source, sucrose revealed the maximum enzyme activity of 226 U ml−1. Yeast extract was found to be the altered nitrogen source in the production medium with 271 U ml−1 of enzyme activity. 10 mg of feathers as substrate, 3% of the microbial inoculum and 72 h of incubation enhanced the enzyme production and exhibited a maximum activity of 378, 408 and 453 U ml−1 respectively. The partially purified keratinase showed maximum specific activity of 528.7 U mg−1 as well as visible degradation of feather, hair and nail after 48 h of incubation confirms the keratinolytic activity.

4 citations

Proceedings ArticleDOI
01 Dec 2017
TL;DR: A combinational method which uses a faster algorithm, Kanade Lucas Tomasi (KLT) for quick verification and a two-step security system, face, Principal component analysis (PCA) and finger print for a more accurate verification is suggested.
Abstract: Security systems are becoming an integral part of our environment, having a secure and accurate security system is of utmost importance. This paper suggests a combinational method which uses a faster algorithm, Kanade Lucas Tomasi (KLT) for quick verification and a two-step security system, face, Principal component analysis (PCA) and finger print for a more accurate verification.

2 citations

Book ChapterDOI
P. Sriramalakshmi1, A. Arvindh1, Sanjeev Kumar1, M. Prasanth1, V.T. Sreedevi1 
01 Jan 2020
TL;DR: A three-phase embedded-type qSBI (E-qSBI) topology which is capable of boosting and inverting the available DC voltage in a single stage is analyzed.
Abstract: A class of single-phase quasi-switched boost inverter (qSBI) topology is developed for low power renewable energy source (RES) applications. This paper analyzes a three-phase embedded-type qSBI (E-qSBI) topology which is capable of boosting and inverting the available DC voltage in a single stage. The operating modes, steady-state analysis, and pulse width modulation (PWM) control of the boost inverter topology are discussed in detail in this work. The E-qSBI supplying, 100 W RL load is designed and simulated with MATLAB/Simulink software tool. The fast Fourier transform analysis (FFT) of output voltage waveform is carried out and the harmonic profile is presented. The simulation results are presented to show the effectiveness of single-stage embedded-type qSBI topology.

1 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: Recombinant technology represents a promising approach for the production of NK with high purity for its use in antithrombotic applications and opportunities for utilizing plant systems for the large-scale production are discussed.
Abstract: Natto, a fermented soybean product, has been consumed as a traditional food in Japan for thousands of years. Nattokinase (NK), a potent blood-clot dissolving protein used for the treatment of cardiovascular diseases, is produced by the bacterium Bacillus subtilis during the fermentation of soybeans to produce Natto. NK has been extensively studied in Japan, Korea, and China. Recently, the fibrinolytic (anti-clotting) capacity of NK has been recognized by Western medicine. The National Science Foundation in the United States has investigated and evaluated the safety of NK. NK is currently undergoing a clinical trial study (Phase II) in the USA for atherothrombotic prevention. Multiple NK genes have been cloned, characterized, and produced in various expression system studies. Recombinant technology represents a promising approach for the production of NK with high purity for its use in antithrombotic applications. This review covers the history, benefit, safety, and production of NK. Opportunities for utilizing plant systems for the large-scale production of NK, or for the production of edible plants that can be used to provide oral delivery of NK without extraction and purification are also discussed.

101 citations

Journal ArticleDOI
TL;DR: Genetic engineering, protein engineering, fermentation optimization and process control have been proved to be the effective strategies for enhancement of nattokinase production and the prospect of microbial nattkinase production was discussed regarding the recent progress, challenge, and trends in this field.
Abstract: Nattokinase (EC 3.4.21.62) is a profibrinolytic serine protease with a potent fibrin-degrading activity, and it has been produced by many host strains. Compared to other fibrinolytic enzymes (urokinase, t-PA and streprokinase), nattokinase shows the advantages of having no side effects, low cost and long life-time, and it has the potential to be used as a drug for treating cardiovascular disease and served as a functional food additive. In this review, we focused on screening of producing strains, genetic engineering, fermentation process optimization for microbial nattokinase production, and the extraction and purification of nattokinase were also discussed in this particular chapter. The selection of optimal nattokinase producing strain was the crucial starting element for improvement of nattokinase production. Genetic engineering, protein engineering, fermentation optimization and process control have been proved to be the effective strategies for enhancement of nattokinase production. Also, extraction and purification of nattokinase are critical for the quality evaluation of nattokinase. Finally, the prospect of microbial nattokinase production was also discussed regarding the recent progress, challenge, and trends in this field.

32 citations

Journal ArticleDOI
TL;DR: A comprehensive review of twenty sequenced peptidases with keratinolytic activity from the serine protease and metalloprotease families is presented, which compares their biochemical activities and highlights the difficulties associated with the interpretation of these data.
Abstract: Keratins are important structural proteins produced by mammals, birds and reptiles. Keratins usually act as a protective barrier or a mechanical support. Millions of tonnes of keratin wastes and low value co-products are generated every year in the poultry, meat processing, leather and wool industries. Keratinases are proteases able to breakdown keratin providing a unique opportunity of hydrolysing keratin materials like mammalian hair, wool and feathers under mild conditions. These mild conditions ameliorate the problem of unwanted amino acid modification that usually occurs with thermochemical alternatives. Keratinase hydrolysis addresses the waste problem by producing valuable peptide mixes. Identifying keratinases is an inherent problem associated with the search for new enzymes due to the challenge of predicting protease substrate specificity. Here, we present a comprehensive review of twenty sequenced peptidases with keratinolytic activity from the serine protease and metalloprotease families. The review compares their biochemical activities and highlights the difficulties associated with the interpretation of these data. Potential applications of keratinases and keratin hydrolysates generated with these enzymes are also discussed. The review concludes with a critical discussion of the need for standardized assays and increased number of sequenced keratinases, which would allow a meaningful comparison of the biochemical traits, phylogeny and keratinase sequences. This deeper understanding would facilitate the search of the vast peptidase family sequence space for novel keratinases with industrial potential.

31 citations

Journal ArticleDOI
TL;DR: In this paper, a low-cost fermentation medium for the growth of Bacillus subtilis and nattokinase production was used, where yeast extract was used as the best nitrogen source.
Abstract: In this study, cheese whey – a nutrient-rich industrial waste was utilized as a low-cost fermentation medium for the growth of Bacillus subtilis and nattokinase production. The nattokinase yield (caseinolytic activity) using cheese whey (789.93 U ml−1) was 5 %–7 % less compared to glucose- or lactose-based synthetic media (833.44 and 850.84 U ml−1, respectively). Effect of nitrogen supplementation (yeast extract, tryptone, and peptone) on nattokinase yield was tested adopting an L9 (33) Taguchi experimental design, which revealed yeast extract as the best nitrogen source. Yeast extract supplementation (10 g l-1) to cheese whey increased the caseinolytic activity to 833.43 U ml−1, making it comparable to lactose- and glucose-based synthetic media, while lowering the medium cost by 55–60 %. A dynamic model incorporating logistic growth, substrate utilization and Luedeking-Piret product formation kinetics across all carbon-sources offered good agreement (R2 > 0.93). The estimated maximum specific growth rate on lactose-based synthetic medium (0.204 h−1), or yeast extract supplemented cheese whey medium (0.201 h−1) were better than that of the glucose-based synthetic medium (0.122 h−1). A similar observation on the growth associated product formation parameters offers insight on medium selection process. Overall, this study suggested that cheese whey could be utilized as a low-cost medium for nattokinase production.

16 citations