Optimization of process parameters for the production of naringinase by Aspergillus niger MTCC 1344

Aspergillus niger MTCC 1344 was used to produce extracellular naringinase in a complex (molasses, yeast extract and salts) medium. An initial medium pH 4.5 and cultivation temperature 30 &deg;C were optimal for enzyme production. Among various carbon and organic nitrogen sources used, molasses and peptone were the most effective for enzyme yield. The rate of enzyme production was enhanced when metal ions were added to the medium. Fermentation conditions are described which produced a higher rate of enzyme synthesis. An increase in initial sugar concentration from 6 to 10 g l&minus;1 in the fermentation medium produced decreased naringinase synthesis while cell mass growth increased with the increase of sugar concentration. At a higher sugar level (10 g l&minus;1) the production of cell mass decreased.<br /

New chemical and chemo-enzymatic synthesis of (RS)-, (R)-, and (S)-esmolol

AbstractOne of the β-adrenergic receptor blocking agents, esmolol, is synthesized in its racemic (RS) and enantio enriched forms (R and S) by a new chemical and chemo-enzymatic route. The enantio-pure intermediates (R) and (S)-methyl 3-(4-(3-chloro-2-hydroxypropoxy)phenyl)propanoate were synthesized from the corresponding racemic alcohol by enzymatic kinetic resolution. The commercially available lipases PCL and CRL showed complementary enantioselectivity in the transesterification reaction of racemic alcohol with vinyl acetate as the acyl donor. The reactions afforded the (R)-alcohol along with (S)-acetate and the (S)-alcohol along with (R)-acetate, respectively, indicating the enzymatic switch for reversal of enantioselectivity. Various reaction parameters such as substrate and enzyme concentration, type of reaction medium, duration of conversion and enantioselectivity were optimized. The (R)- and (S)-alcohols were converted to the (S)- and (R)-esmolol, respectively, on N-alkylation with isopropanolamine. The enzymatically obtained (R)- and (S)-acetates were chemically hydrolyzed to the corresponding alcohols and further converted to (S)- and (R)-esmolol by chemical reactions. These represent the new chemo-enzymatic synthesis of both the enantiomers of the drug. Using chemical routes, the (RS)/(R)/(S)-esmolol were also synthesized from (RS)/(R)/(S)-epichlorohydrin via the corresponding (RS)/(S)/(R)- methyl 3-(4-((oxiran-2-yl)methoxy)phenyl)propanoate and the (RS)/(R)/(S)-methyl 3-(4-(3-chloro-2-hydroxypropoxy)phenyl)propanoate intermediates. This process has given improved overall yield and better enantiomeric excess compared to the reported one

Thermo-mechanical and micro-structural properties of xylanase containing whole wheat bread

Xylanase is a hemicellulase that can hydrolyses the complex polysaccharides. Hemicelluloses are main components of cell walls of cereal grains. Moreover, hemicelluloses are considered as potential sources of mono- and oligosaccharides. In this study, influence of xylanase on the physicochemical properties and sensory qualities of the whole wheat bread during storage was investigated. Studies of whole wheat bread on microstructure, texture, thermotics, Scanning Electron Microscopic (SEM), X-Ray Diffraction (XRD) were conducted at ambient temperature of 25 and 4 °C respectively. During storage at different temperatures, bread containing xylanase exhibited less firmness but larger volume with whiter crumb color and longer shelf life as compared to control bread. Results of firmness, enthalpy, Fourier Transformation Infra Red (FTIR) and X-Ray Diffraction (XRD) studies suggested a lower staling rate of bread containing xylanase as compared to control one. Bread containing xylanase showed a smoother surface and more uniform pore size than the control. Significant differences in microstructure of control and bread containing xylanase were observed which might be attributed due to the change in water starch gluten interaction. These differences were also found to be interrelated to the textural properties of bread. Better sensory features were achieved in bread containing xylanase

Prospects of biodiesel production from microalgae in India

Energy is essential and vital for development, and the global economy literally runs on energy. The use of fossil fuels as energy is now widely accepted as unsustainable due to depleting resources and also due to the accumulation of greenhouse gases in the environment. Renewable and carbon neutral biodiesel are necessary for environmental and economic sustainability. Biodiesel demand is constantly increasing as the reservoir of fossil fuel are depleting. Unfortunately biodiesel produced from oil crop, waste cooking oil and animal fats are not able to replace fossil fuel. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Production of biodiesel using microalgae biomass appears to be a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. Microalgae are photosynthetic microorganisms which convert sunlight, water and CO2 to sugars, from which macromolecules, such as lipids and triacylglycerols (TAGs) can be obtained. These TAGs are the promising and sustainable feedstock for biodiesel production. Microalgal biorefinery approach can be used to reduce the cost of making microalgal biodiesel. Microalgal-based carbon sequestration technologies cover the cost of carbon capture and sequestration. The present paper is an attempt to review the potential of microalgal biodiesel in comparison to the agricultural crops and its prospects in India.Biodiesel Microalgae Triacylglycerol Algal reactors Biorefinery

Management protocols for chronic heart failure in India

Heart failure is a common clinical syndrome and a global health priority. The burden of heart failure is increasing at an alarming rate worldwide as well as in India. Heart failure not only increases the risk of mortality, morbidity and worsens the patient’s quality of life, but also puts a huge burden on the overall healthcare system. The management of heart failure has evolved over the years with the advent of new drugs and devices. This document has been developed with an objective to provide standard management guidance and simple heart failure algorithms to aid Indian clinicians in their daily practice. It would also inform the clinicians on the latest evidence in heart failure and provide guidance to recognize and diagnose chronic heart failure early and optimize management