• Title/Summary/Keyword: enzymes

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Deinking of Electrostatic Wastepaper with Cellulolytic Enzymes and Surfactant in Neutral pH

  • Eom, Tae-Jin;Kim, Kang-Jae;Yoon, Kyoung-Dong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.39 no.5
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    • pp.12-19
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    • 2007
  • Enzymatic deinking method can avoids the alkaline environment as usual required in chemical deinking, which consequently cuts chemical costs and reduced the white water pollution. The electrostatic wastepaper was dinked with commercial cellulolytic enzymes and surfactant in neutral pH and the effectiveness of deinking and the physical properties of deinked pulp were evaluated. The disintegrating efficiency of the electrostatic wastepaper in neutral pH was enhanced with enzyme treatments. Although the freeness of deinked pulp with enzymes was higher than that of deinked pulp with chemical de inking agents, the brightness of the enzymatic deinked pulp was slightly lower than that of the chemical deinked pulp. But, by additions of nonionic surfactants, the brightness of deinked pulp was increased with less residual ink particles and mechanical properties of enzymatic deinked pulp was improved compared to the deinked pulp of conventional alkaline method.

Applications of Proteolytic Enzymes from Kiwifruit on Quality Improvements of Meat Foods in Foodservice

  • Lee, Kyung-A;Jung, Sook-Hee;Park, In-Shik
    • Food Science of Animal Resources
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    • v.30 no.4
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    • pp.669-673
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    • 2010
  • The purpose of this study was to evaluate kiwifruit as a tenderizer by its effects in improving the quality of various beef parts. Basic data are provided for development of standard recipes for convenient cooking in foodservice. The optimum temperature of the crude proteolytic enzymes in the kiwifruit was determined to be $65^{\circ}C$. The substrate specificity of the enzymes was higher in beef than in pork, chicken, or duck. The enzymes had their greatest effects on chuck and rib parts, and had lower effects on loin, breast, and round parts, in that order. As the amount of kiwifruit extract increased, the moisture content of the cooked beef also increased. The addition of 10% kiwifruit improved the sensory quality of the cooked beef. In particular, the texture scores of cooked beef samples treated with 10% and 15% kiwifruit extract were significantly higher than the other samples (p<0.001), and juiciness and overall acceptability scores were also highest. In summary, 10% kiwifruit extract is deemed an appropriate addition to improve.

Effect of 2,4,5-Trichlorobiphenyl (PCB-29) on Oxidative Stress and Activities of Antioxidant Enzymes in Tomato Seedlings

  • Cho, Un-Haing;Sohn, Ji-Young
    • The Korean Journal of Ecology
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    • v.25 no.6
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    • pp.371-377
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    • 2002
  • Leaves of two-week old seedlings of tomato (Lycopersicon esculentum) were treated with various concentrations (0, 0.2 and 0.4 $\mu$g/1) of 2,4,5-trichlorobiphenyl (PCB-29) and subsequent growth of seedlings, symptoms of oxidative stress and activities of antioxidant enzymes were investigated. Compared with the non-treated control, foliar application of PCB-29 decreased both biomass and superoxide ($O_2$) radical production but increased hydrogen peroxide production and lipid peroxidation such as malondialdehyde (MDA) formation with increased activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX). Further studies on the isozymes of SOD, peroxidase (POD) and APX showed that all three isozymes of SOD such as Mn-SOD, Fe-SOD and Cu/Zn-SOD, two among four isozymes of POD and all three isozymes of APX were selectively increased in response to PCB. Therefore, we suggest that a possible cause for the reduction of seedling growth by PCB exposure is the oxidative stress including over production of hydrogen peroxide and the selective expression of specific isozymes of some antioxidant enzymes.

Exploiting Gastrointestinal Microbes for Livestock and Industrial Development - Review -

  • Singh, Birbal;Bhat, Tej K.;Singh, Bhupinder
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.4
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    • pp.567-586
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    • 2001
  • Gastrointestinal tract of ruminants as well as monogastric animals are colonised by a variety of microorganisms including bacteria, fungi and protozoa. Gastrointestinal ecosystem, especially the rumen is emerging as an important source for enrichment and natural selection of microbes adapted to specific conditions. It represents a virtually untapped source of novel products (e.g. enzymes, antibiotics, bacteriocins, detoxificants and aromatic compounds) for industrial and therapeutic applications. Several gastrointestinal bacteria and fungi implicated in detoxification of anti-nutritional factors (ANFs) can be modified and manipulated into promising system for detoxifying feed stuffs and enhancing fibre fermentation both naturally by adaptation or through genetic engineering techniques. Intestinal lactobacilli, bifidobacteria and butyrivibrios are being thoroughly investigated and widely recommended as probiotics. Restriction endonucleases and native plasmids, as stable vectors and efficient DNA delivery systems of ruminal and intestinal bacteria, are increasingly recognised as promising tools for genetic manipulation and development of industrially useful recombinant microbes. Enzymes can improve the nutrient availability from feed stuffs, lower feed costs and reduce release of wastes into the environment. Characterization of genes encoding a variety of commercially important enzymes such as cellulases, xylanases, $\beta$-glucanases, pectinases, amylases and phytases will foster the development of more efficacious and viable enzyme supplements and enzyme expression systems for enhancing livestock production.

Comparison of Milk-clotting Activity of Proteinase Produced by Bacillus Subtilis var, natto and Rhizopus oligosporus with Commercial Rennet

  • Chen, Ming Tsao;Lu, Ying Yu;Weng, Tien Man
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.10
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    • pp.1369-1379
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    • 2010
  • This study investigated purification and milk-clotting activity of the enzymes produced by Bacillus subtilis var, natto and Rhizopus oligosporus compared with that of commercial rennet. The clotting time, viscosity, tension and microstructure of the curd and electrophoretic patterns of milk proteins were determined. The milk-clotting activity/proteolytic activity ratios (MCA/PA ratio) of B. subtilis, R. oligosporus and commercial rennet were also compared. The results revealed that the curd formed by the commercial rennet had the highest viscosity and curd tension and the shortest clotting time among the three enzymes. However, curd produced by Rhizopus enzymes was ranked as second. From the MCA/PA ratio and electrophoretogram analyses it could be concluded that the enzyme produced by B. subtilis had the highest proteolytic activity, while the commercial rennet had the highest milk-clotting activity. Observations of microstructures of SEM showed that the three-dimensional network for curd formed by commercial rennet was denser, firmer and more smooth. The milk-clotting activity, specific activity, purification ratio and recovery of the purified enzymes produced by both the tested organisms were also determined with ion exchange chromatography and gel filtration.

EFFECTS OF DIETARY PROTEINS ON THE ACTIVITIES OF LIPOGENIC ENZYMES IN THE LIVER OF GROWING CHICKS

  • Tanaka, K.;Okamoto, T.;Ohtani, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.1
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    • pp.123-128
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    • 1992
  • In Experiment 1, when fasted chicks were fed diets containing various sources of protein for 3 days, the activities of lipogenic enzymes (acetyl-CoA carboxylase, fatty acid synthetase, citrate cleavage enzyme and malic enzyme) in the liver of growing chicks were significantly lower in the soybean protein or gluten diet than in the casein or fish protein diet. Triglycride contents of the liver and plasma of chicks fed the casein or fish protein diet were significantly lower than that of those fed soybean protein or gluten diet. In Experiment 2, the effects of dietary amino acid mixture simulating casein or protein on the activities of hepatic lipogenic enzymes were examined. The activities of acetyl-CoA carboxylase and fatty acid synthetase in the liver of chicks fed the casein diet were significantly higher than that of those fed the soybean protein diet or two diets of amino acid mixtures. Furthermore, there were no significant differences between the two diets of amino acid mixture based on casein or soybean protein. However, the activities of malic enzyme and citrate cleavage enzyme tended to be lower in the soybean-type amino acid diet than in the casein-type amino acid diet. Thus, some effects can be ascribed to the protein itself and some to the amino acid composition of the protein sources.

Development of Gastric and Pancreatic Enzyme Activities and Their Relationship with Some Gut Regulatory Peptides in Grazing Sheep

  • Xia, Lang;Cailian, Wang
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.4
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    • pp.500-508
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    • 2011
  • Forty-four Gansu Alpine Fine-wool lambs were used to study changes in the activities of three gastric and five pancreatic enzymes under grazing conditions between 0 and 56 days of age. The lambs were slaughtered on days 0, 3, 7, 14, 21, 28, 42 and 56, the abomasal contents, mucosa and pancreas were immediately removed and placed into liquid nitrogen and enzyme activities were determined. Gastric enzyme (chymosin, pepsin and pregastrc esterase) activities were relatively high at birth, especially chymosin, but decreased quickly between day 0 and 21. The activity of pepsin changed insignificantly with increasing age. There was no significant change in the pancreatic enzyme activities (trypsin, chymotrypsin, ${\alpha}$-amylase, lipase and lactase). The activity of trypsin was relatively higher than that of the other pancreatic enzymes, and lactase activity was low. These ontogenic patterns might be under the control of many gut regulatory peptides, the plasma concentrations of which changed simultaneously. Some gastric and pancreatic enzymes were correlated with plasma concentrations of these gut regulatory peptides.

Inference of Aspergillus fumigatus Pathways by Computational Genome Analysis: Tricarboxylic Acid Cycle (TCA) and Glyoxylate Shunt

  • Do, Jin-Hwan;Anderson, Michael-J.;Denning, David-W.;Erich, Bornberg-Bauer
    • Journal of Microbiology and Biotechnology
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    • v.14 no.1
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    • pp.74-80
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    • 2004
  • Aspergillus fumigatus is one of the most common fungi in the human environment, both in-doors and out-doors. It is the main causative agent of invasive aspergillosis, a life-threatening mycosis among immunocompromised patients. The genome has been sequenced by an international consortium, including the Wellcome Trust Sanger Institute (U.K.) and The Institute for Genomic Research (TIGR, U.S.A.), and a ten times whole genome shotgun sequence assembly has been made publicly available. In this study, we identified tricarboxylic acid (TCA) cycle enzymes of A. fumigatus by comparative analysis with four other fungal species. The open reading frames showed high amino acid sequence similarity with the other fungal citric acid enzymes and well-conserved functional domains. All genes present in Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida albicans, and Neurospora crassa were also found in A. fumigatus. In addition, we identified four A. fumigatus genes coding for enzymes in the glyoxylate shunt, which may be required for fungal virulence. The architecture of multi-gene encoded enzymes, such as isocitrate dehydrogenase, 2-ketoglutarate, succinyl-CoA synthetase, and succinate dehydrogenase was well conserved in A. fumigatus. Furthermore, our results show that genes of A. fumigatus can be detected reliably using GlimmerM.

Reactive Dyeing of Bio Pretreated Cotton Knitted Fabrics

  • Ayoub, Alvira;Ali, Iftikhar;Son, Eun Jong;Jeong, Sung Hoon
    • Textile Coloration and Finishing
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    • v.26 no.4
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    • pp.283-289
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    • 2014
  • This study describes the feasibility and optimization of reactive dyeing on bio treated cotton knitted fabrics. For this, cotton knitted fabrics distinctly with two different enzymes, alkaline Pectinases(Scourzyme $L^{(R)}$) and Pectate lyases(Bactosol Co. ip $liquor^{(R)}$). In this way by increasing the concentration and processing temperature, the access of enzymes towards the fatty and waxy substrate was found to be accelerated. To achieve higher absorbency and whiteness index, a series of experiments was carried out to assure that Pectate lyases enzymes possesses high access towards the fats and waxes at high temperature. To this end, cotton knitted fabrics was dyed without oxidative bleaching step. The Pectate lyases scoured and dyed fabrics showed less color difference when 2% dye shade is used. The fabrics pre-scoured with Pectate lyases showed good the light and washing fastness properties, compared to the conventional and Pectinases dyed fabrics. However pectinases enzymes showed lower activity at high temperature, caused poor wettability and whiteness index of fabrics. The improvement of the accessibility of enzyme to the pectin at higher temperature Pectate lyases treatment before dyeing was found to be useful for subsequent pectin degradation in cotton knitted fabrics.

Enzymatic Hydrolysis of Pretreated Chitin by Aspergillus carneus Chitinase

  • Mohamed, Abdel-Naby;Kwon, Dae-Young
    • Journal of Microbiology and Biotechnology
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    • v.2 no.3
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    • pp.197-203
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    • 1992
  • Studies of the pretreatment of chitin and its subsequent hydrolysis by Aspergillus carneus chitinase are reported. Ball milling was found to be the most effective way among the pretreatment methods tested. Data are presented describing the effect of enzyme and substrate concentrations on the rate and extent of the hydrolysis process. It was found that the successive addition of enzyme improved the saccharification yield. Significant product inhibition of the chitinase was observed when N-acetylglucosamine concentration was 3.6% or higher. Adsorption of enzymes to the substrate occurred during a 24 hr hydrolysis period. An initial rapid and extensive adsorption occurred, followed by gradual desorption which increased during the time of reaction. Intermediate removal of the hydrolyzate and continuation of the hydrolysis by adsorbed enzyme on the residual chitin was also investigated. A total of 75.4 g/l reducing sugars, corresponding to 69.2% saccharificaton yield (as N-acetylglucosamine) was obtained. In addition an increase in the amount of recoverable enzymes was observed under these conditions. Evidence presented here suggests that the technique, whereby the free enzymes in the recovered hydrolyzate are re-adsorbed onto the new substrate, may provide a means of recirculating the dissolved enzymes.

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