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Commercial Enzymes (commercial + enzyme)
Terms modified by Commercial Enzymes Selected AbstractsComparison of Commercial Enzymes for the Processing of Marula Pulp, Wine, and SpiritsJOURNAL OF FOOD SCIENCE, Issue 6 2002M. Fundira ABSTRACT: Commercial enzymes were compared in this study to improve the yield and clarification of marula fruit (Sclerocarya berria sub. caffra) juice. An increase in yield of up to 12% in juice treated with the enzyme Rapidase Filtration was recorded. A 15-fold improvement in juice clarity and an increase in total terpenes were observed after treatment with prefermentation processing enzymes. Post-fermented marula wine was treated with enzymes to hydrolyze bound monoterpenes. An increase in the free monoterpenes of at least 92% was observed in enzyme-treated juice. The different enzymes had both positive and negative effects on the flavor of the juice, wine, and distillate. Trenolin Bukett increased the aroma profile of the wine, while it remained closely related to the unaltered marula profile of the control. AR2000 had an overwhelming effect on the flavor profile, but the risk of deviating from the typical marula flavor was high. [source] Lactic acid fermentation of food waste using integrated glucoamylase productionJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2009Xiao Qiang Wang Abstract Commercial enzyme is usually needed for the bioconversion of organic waste or biomass. The overall cost could be reduced very significantly if enzyme production could be integrated with its application, avoiding unnecessary steps in enzyme production (such as concentration, recovery and transportation). This investigation attempted to integrate crude glucoamylase production with lactic acid fermentation of food waste. A maximum glucoamylase activity of 1850 U g,1 was obtained with Aspergillus nigerduring solid-state fermentation (SSF) of food waste, 14.8 times more than that obtained during submerged fermentation (SmF). The optimum pH for producing glucoamylase was 4.6, and glucoamylase retained 83.5% of peak activity at pH 3.0. Without any recovery treatment, the glucoamylase produced by SSF could be used directly for lactic acid fermentation of food waste. Lactic acid concentration reached 45.5 g L,1 with the addition of the crude enzyme, 72% higher than the control. No side-effects were caused by the viable A. niger in the crude enzyme. This work successfully integrated glucoamylase production with lactic acid fermentation. The enzyme produced by SSF of food waste had sufficient activity to be used directly without any treatment. The integrated process proposed in this study was very economical and may be helpful to other bioconversions. Copyright © 2008 Society of Chemical Industry [source] Comparison of Commercial Enzymes for the Processing of Marula Pulp, Wine, and SpiritsJOURNAL OF FOOD SCIENCE, Issue 6 2002M. Fundira ABSTRACT: Commercial enzymes were compared in this study to improve the yield and clarification of marula fruit (Sclerocarya berria sub. caffra) juice. An increase in yield of up to 12% in juice treated with the enzyme Rapidase Filtration was recorded. A 15-fold improvement in juice clarity and an increase in total terpenes were observed after treatment with prefermentation processing enzymes. Post-fermented marula wine was treated with enzymes to hydrolyze bound monoterpenes. An increase in the free monoterpenes of at least 92% was observed in enzyme-treated juice. The different enzymes had both positive and negative effects on the flavor of the juice, wine, and distillate. Trenolin Bukett increased the aroma profile of the wine, while it remained closely related to the unaltered marula profile of the control. AR2000 had an overwhelming effect on the flavor profile, but the risk of deviating from the typical marula flavor was high. [source] Performance characteristics of cholesterol oxidase for kinetic determination of total cholesterolJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 6 2005Pornpen Srisawasdi Abstract The enzymatic method for cholesterol determination can use either an endpoint or a kinetic method. Not much is known concerning the properties (Km and Vmax) of the commercial enzyme for the kinetic method. We measured the Km and Vmax of Brevibacterium, Streptomyces, Pseudomonas fluorescens, and Cellulomonas cholesterol oxidase. Brevibacterium gave the highest Km value (230.3×10,4,M), followed by Streptomyces (2.17×10,4,M), Cellulomonas (0.84×10,4,M), and Pseudomonas (0.61×10,4,M). The Km values and the linearity obtained from Streptomyces (2.6,mmol/L), Pseudomonas (2.1,mmol/L), or Cellulomonas (2.1,mmol/L) were too low. Dichlorophenol isomers, acting as inhibitors, increased the enzyme's Km. The addition of 3,4-dichlorophenol raised the Km of Streptomyces from 2.17×10,4 to 24.89×10,4,M. The linearity was increased from 2.6 to 13.0,mmol/L. The high Km of Brevibacterium resulted in an insensitive reaction and low cholesterol linearity (7.8,mmol/L). An increase in the sample-to-reagent ratio from 1:100 to 1:10 enhanced the reaction rate and the linearity from 7.8 to 20.7,mmol/L. We suggest that Brevibacterium and Streptomyces cholesterol oxidase (with the addition of 3,4 dichlorophenol) are good sources for serum cholesterol determination by the kinetic method. J. Clin. Lab. Anal. 19:247,252, 2005. © 2005 Wiley-Liss, Inc. [source] Influence of silica gel in production of diacylglycerol via enzymatic glycerolysis of palm oleinEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 6 2009Chiou Moi Yeoh Abstract Enzymatic glycerolysis was explored in this paper for the production of diacylglycerol (DAG) oils from palm olein. Three commercial enzymes, Lipozyme TL,IM, Lipozyme RM,IM and Novozym 435 were used for their ability to synthesize DAG in a solvent-free system. Novozym 435 was found to be the more effective enzyme, resulting in a high DAG production even in the absence of an adsorbent such as silica gel. The yields of DAG were between 43 and 50,wt-%. Lipozyme TL,IM and RM,IM, being supported on hydrophilic materials, require an adsorbent to allow slow release of glycerol for reaction with the enzyme and oil. In the absence of silica, no reaction was observed. The success of the reaction is therefore very dependent on the amount of silica used. The yields of DAG using Lipozyme TL,IM and RM,IM were 52 and 45,wt-%, respectively. In addition, the degree of reduction in tocopherols and tocotrienols appeared correlated with the efficacy of the glycerolysis reaction. Changes in the slip melting points and solid fat contents of the products are indicative of the reaction occurring. [source] The influence of pH and digestion with commercial enzymes on calcium adsorption in casabeINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2006Petra Beatriz Navas Summary The Ca2+ binding capacity of a sample of casabe made from cassava (Manihot esculenta) was evaluated by using adsorption isotherms after a digestion process with commercial enzymes. It was found that enzymatic treatment increased the ability of vegetable material to retain calcium and to release endogenous mineral ions as a consequence of possible modifications to the carbohydrate matrix. Untreated casabe did not release mineral ions. pH also influenced the retention of Ca2+: at pH 4.5 release was the main process but adsorption increases with alkalinity up to pH 8.5. The Ca concentrations at which neither adsorption nor release occurred [Ca2+]e were as follows: 5.2 mm (pH 4.5), 3.5 mm (pH 7.1), and 0.63 mm (pH 8.5). The pH effect was explained by an increase in the density of negatively charged functional groups produced by ionization reactions at pH below the point of zero net charge (pHo) which was evaluated by using the Gouy,Chapman double layer model. Values of pHo were 6.4 for raw material and 4.1 after digestion with enzymes. In both cases, the density of positively charged sites below pHo was much higher that the density of negatively charged sites above pHo. [source] Enzymatic Production of l -Menthol by a High Substrate Concentration Tolerable Esterase from Newly Isolated Bacillus subtilis ECU0554ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2009Gao-Wei Zheng Abstract Enzymatic preparation of l -menthol has been attracting much attention in the flavor and fragrance industry. A new ideal strain, Bacillus subtilis ECU0554, which exhibited high hydrolytic activity and excellent enantioselectivity towards l -menthyl ester, has been successfully isolated from soil samples through enrichment culture and identified as Bacillus subtilis by 16S rDNA gene sequencing. The esterase extracted from B. subtilis ECU0554 (BSE) showed the best catalytic properties (E>200) for dl -menthyl acetate among the five menthyl esters examined. Enantioselective hydrolysis of 100,mM dl -menthyl acetate at 30°C and pH,7.0, using crude BSE as biocatalyst and 10% ethanol (v/v) as cosolvent, resulted in 49.0% conversion (3,h) and 98.0% ee for the l -menthol produced, which were much better than those using commercial enzymes tested. Moreover, BSE exhibited strong tolerance against high substrate concentration (up to 500,mM), and the concentration of l -menthol produced could reach as high as 182,mM, and more importantly, the optical purity of l -menthol produced was kept above 97% ee, which were not found in previous reports. These results imply that BSE is a potentially promising biocatalyst for the large-scale enzymatic preparation of l -menthol. Using this excellent biocatalyst, the enzymatic production of l -menthol will become a mild, efficient, inexpensive and easy-to-use "green chemistry" methodology. [source] Newly isolated Streptomyces spp. as enantioselective biocatalysts: hydrolysis of 1,2-O-isopropylidene glycerol racemic estersJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2005F. Molinari Abstract Aims:, To identify microbial strains with esterase activity able to enantioselectively hydrolyse esters of (R,S)-1,2-O-isopropylidene glycerol. Methods and Results:, The microbial hydrolysis of various racemic esters of 1,2-O-isopropylidene glycerol (IPG) was attempted by screening among Streptomyces spp. previously selected on the basis of their carboxylesterase activity. The best results were observed in the hydrolysis of butyrate ester and two strains appeared promising as they showed opposite enantioselectivity: Streptomyces sp. 90852 gave predominantly (S)-IPG, while strain 90930 mostly gave the R -alcohol. Streptomyces sp. 90930 was identified as Streptomyces violaceusniger, whereas Streptomyces sp. 90852 is a new species belonging to the Streptomyces violaceus taxon. The carboxylesterase belonging to strain 90852 gave a maximum value of enantiomeric ratio (E) of 14,16. This strain was lyophilized and used as dry mycelium for catalysing the synthesis of isopropylidene glycerol butyrate in heptane showing reaction rate and enantioselectivity (E = 6·6) lower than what observed for the hydrolysis. Conclusions:, A new esterase with enantioselective activity towards (R,S)-IPG butyrate has been selected. The best enantioselectivity is similar or even better than the highest reported value in the literature with commercial enzymes. The enzyme is produced by a new species belonging to the S. violaceus taxon. Significance and Impact of the Study:, New esterases from streptomycetes can be employed for the enantioselective hydrolysis of chiral esters derived from primary alcohols, not efficiently resolved with commercial enzymes. [source] ESR SPECTROSCOPY INVESTIGATION OF ANTIOXIDANT ACTIVITY AND PROTECTIVE EFFECT ON HYDROXYL RADICAL-INDUCED DNA DAMAGE OF ENZYMATIC EXTRACTS FROM PICRORRHIZA KURROAJOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2008SOUNG-HEE CHOI ABSTRACT The potential antioxidant activity of enzymatic extracts from Picrorrhiza kurroa was evaluated on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, hydroxyl radical and alkyl radical-scavenging activities using an electron spin resonance spectrometer (JEOL Ltd., Tokyo, Japan). P. kurroa was enzymatically hydrolyzed by seven carbohydrases and five proteases to prepare water-soluble extracts. The DPPH radical-scavenging activities of the pancreatic trypsin and Amyloglucosidase (AMG) (artificial carbohydrase by Novozyme Nordisk, Bagsvaerd, Denmark) extracts from P. kurroa were the highest among protease and carbohydrase extracts, and 50% inhibitory concentration (IC50) values were 35.58 and 29.03 µg/mL, respectively. The hydroxyl radical-scavenging activity of the Protamex and Viscozyme extracts from P. kurroa were the highest scavenging activities, and the IC50 values were 0.46 and 1.89 mg/mL, respectively. In addition, the Protamex and Maltogenase extracts from P. kurroa showed the highest alkyl radical-scavenging activities, and the IC50 values were 18.03 and 10.66 µg/mL, respectively. The protective effect of the Protamex extracts from P. kurroa on DNA damage which was free radical-induced was 92% at 3 mg/mL. These results indicate that enzymatic extracts of P. kurroa show potent antioxidant activity. PRACTICAL APPLICATIONS Picrorrhiza kurroa could be used to produce protein and carbohydrate extracts with antioxidative activity. Many industrial commercial enzymes such as Promozyme, Celluclast 1.5 L FG, Maltogenase L, Viscozyme L, Termamyl SC, Dextrozyme E, AMG 300 L, Protamex, Flavourzyme 500 MG, Neutrase 0.8 L, Pancreatic Trypsin and Alcalase 2.4 L could be also used to attain the extracts processing the high antioxidative activity. The extracts can be used as natural antioxidants. [source] Solubilisation of proteins from rayfish residues by endogenous and commercial enzymesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2004Laura Pastoriza Abstract The aim of the present study was to design methods for the digestion of fish proteins from processing wastes, leading to new possibilities for little-used species or those generating a significant volume of residues. Residues of rayfish (Raja clavata) were used for the solubilisation of protein by hydrolysis treatment. The kinetics of hydrolysis was studied using rayfish enzymes, either by autolysis of the protein in a triturate of the raw material or by application of a multi-enzyme preparation previously extracted from the viscera of the species. Their effectiveness was compared with that of two commercial enzymes, papain and pepsin. Optimum conditions of hydrolysis and enzymatic activity for digestion with rayfish enzymes were ascertained. The yield of material and the efficiency of digestion in each of the hydrolysis processes are reported. Copyright © 2003 Society of Chemical Industry [source] Evaluation of different protein sources for aquafeeds by an optimised pH-stat systemJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2002Francisco J Alarcón Abstract This paper presents the results of some experiments oriented to optimise and standardise the measurement of protein hydrolysis by fish proteases using the pH-stat technique. Various factors affecting the degree of hydrolysis (DH) were considered (autohydrolysis of the protein sources, type of enzymes utilised, substrate/enzyme ratio and effect of inhibitors). The crude extracts obtained from fish digestive tissues showed their suitability for the determination of protein hydrolysis, rendering better results than those obtained using mixtures of commercial enzymes. DH values for a given protein were greatly affected by the substrate/enzyme ratio, since small modifications in protein concentration resulted in significant variations in DH. Protease inhibitors present in various plant protein sources produced a reduction in DH values. © 2002 Society of Chemical Industry [source] | |||||||||||||