T.S. Chandra

Bio: T.S. Chandra is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Eleusine & Xylanase. The author has an hindex of 27, co-authored 67 publications receiving 2395 citations. Previous affiliations of T.S. Chandra include Indian Institutes of Technology & Indian Institute of Science.

Molybdenum‐dependent sulfur oxidation in facultatively lithoautotrophic thiobacteria

Abstract: Molybdenum is required for lithoautotrophic growth with thiosulfate by Paracoccus denitrificans, Thiobacillus versutus, and Thiosphaera pantotropha. Tungstate inhibits growth with thiosulfate, molybdate reverses this inhibition. T. pantotropha contains the molybdenum cofactor while a pleiotropic mutant, unable to oxidize thiosulfate does not. This suggests that thiosulfate oxidation involves a molybdoenzyme catalyzing a hydroxylation reaction.

Production and partial characterization of a novel capsular polysaccharide KP-EPS produced by Paenibacillus pabuli strain ATSKP

Abstract: The aerobic nitrogen fixing xylanolytic bacterium Paenibacillus pabuli strain ATSKP produces loosely attached capsular polysaccharide KP-EPS. On 0.5% birchwood xylan 70 ± 5.02 mg of KP-EPS was produced per gram dry weight of cells by the fourth day of growth in the absence of combined nitrogen source at 30°C. It was separated and purified using centrifugation, cold acetone precipitation and dialysis and is a sulfate containing heteropolymer as revealed by FT-IR spectrometry and elemental analysis. CHN analysis revealed the presence of 37.50% carbon, 5.90% hydrogen and 8.28% nitrogen in KP-EPS. Absence of phosphorus was confirmed by 31P NMR. ICP-OES analysis showed the presence of various metals in small concentrations. Specific binding with aniline blue suggested the presence of (1,3)-β-d-glucan. Thermal gravimetric analysis and differential scanning calorimetric analysis confirmed its thermal stability as high as 200°C. The EPS was not pseudo plastic and the viscosity was less than xanthan. The intrinsic viscosity did not reduce drastically when dissolved in 0.1 M NaCl.

Purification and Characterization of Novel Halo-Acid-Alkali-Thermo-stable Xylanase from Gracilibacillus sp. TSCPVG

Abstract: An aerobic xylanolytic moderately halophilic and alkali-tolerant bacterium, Gracilibacillus sp. TSCPVG, produces multiple xylanases of unusual halo-acid-alkali-thermo-stable nature. The purification of a major xylanase from TSCPVG culture supernatant was achieved by hydrophobic and gel permeation chromatographic methods followed by electroelution from preparatory PAGE. The molecular mass of the purified xylanase was 42 kDa, as analyzed by SDS-PAGE, with a pI value of 6.1. It exhibited maximal activity in 3.5 % NaCl and retained over 75 % of its activity across the broad salinity range of 0–30 % NaCl, indicating a high halo-tolerance. It showed maximal activity at pH 7.5 and had retained 63 % of its activity at pH 5.0 and 73 % at pH 10.5, signifying the tolerance to broad acid to alkaline conditions. With birchwood xylan as a substrate, K m and specific activity values were 21 mg/ml and 1,667 U/mg, respectively. It is an endoxylanase that degrades xylan to xylose and xylobiose and had no activity on p-nitrophenyl-β-d-xylopyranoside, p-nitrophenyl-β-d-glucopyranoside, p-nitrophenyl acetate, carboxymethylcellulose, and filter paper. Since it showed remarkable stability over different salinities, broad pH, and temperature ranges, it is promising for application in many industries.

Xylanases, xylanase families and extremophilic xylanases

Abstract: Xylanases are hydrolytic enzymes which randomly cleave the β 1,4 backbone of the complex plant cell wall polysaccharide xylan. Diverse forms of these enzymes exist, displaying varying folds, mechanisms of action, substrate specificities, hydrolytic activities (yields, rates and products) and physicochemical characteristics. Research has mainly focused on only two of the xylanase containing glycoside hydrolase families, namely families 10 and 11, yet enzymes with xylanase activity belonging to families 5, 7, 8 and 43 have also been identified and studied, albeit to a lesser extent. Driven by industrial demands for enzymes that can operate under process conditions, a number of extremophilic xylanases have been isolated, in particular those from thermophiles, alkaliphiles and acidiphiles, while little attention has been paid to cold-adapted xylanases. Here, the diverse physicochemical and functional characteristics, as well as the folds and mechanisms of action of all six xylanase containing families will be discussed. The adaptation strategies of the extremophilic xylanases isolated to date and the potential industrial applications of these enzymes will also be presented.

Microbial xylanases and their industrial applications: a review.

Abstract: Despite an increased knowledge of microbial xylanolytic systems in the past few years, further studies are required to achieve a complete understanding of the mechanism of xylan degradation by microorganisms and their enzymes. The enzyme system used by microbes for the metabolism of xylan is the most important tool for investigating the use of the second most abundant polysaccharide (xylan) in nature. Recent studies on microbial xylanolytic systems have generally focussed on induction of enzyme production under different conditions, purification, characterization, molecular cloning and expression, and use of enzyme predominantly for pulp bleaching. Rationale approaches to achieve these goals require a detailed knowledge of the regulatory mechanism governing enzyme production. This review will focus on complex xylan structure and the microbial enzyme complex involved in its complete breakdown, studies on xylanase regulation and production and their potential industrial applications, with special reference to biobleaching.

A review on nanofluids: preparation, stability mechanisms, and applications

Abstract: Nanofluids, the fluid suspensions of nanomaterials, have shown many interesting properties, and the distinctive features offer unprecedented potential for many applications. This paper summarizes the recent progress on the study of nanofluids, such as the preparation methods, the evaluation methods for the stability of nanofluids, and the ways to enhance the stability for nanofluids, the stability mechanisms of nanofluids, and presents the broad range of current and future applications in various fields including energy and mechanical and biomedical fields. At last, the paper identifies the opportunities for future research.

Phenolics in food and nutraceuticals

Abstract: Phenolics in Food and Nutraceuticals is the first single-source compendium of essential information concerning food phenolics. This unique book reports the classification and nomenclature of phenolics, their occurrence in food and nutraceuticals, chemistry and applications, and nutritional and health effects. In addition, it describes antioxidant activity of phenolics in food and nutraceuticals as well as methods for analysis and quantification. Each chapter concludes with an extensive bibliography for further reading. Food scientists, nutritionists, chemists, biochemists, and health professionals will find this book valuable.