• Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.12.1-12.8
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• 2016

Roe is the term used to describe fish eggs (oocytes) gathered in skeins and is one of the most valuable food products from fishery sources. Thus, means of processing are required to convert the underutilized yellowfin tuna roes (YTR) into more marketable and acceptable forms as protein concentrate. Roe protein concentrates (RPCs) were prepared by cooking condition (boil-dried concentrate, BDC and steam-dried concentrate, SDC, respectively) and un-cooking condition (freeze-dried concentrate, FDC) from yellowfin tuna roe. The yield of RPCs was in the range from 22.2 to 25.3 g/100 g of roe. RPCs contained protein (72.3-77.3 %), moisture (4.3-5.6 %), lipid (10.6-11.3 %) and ash (4.3-5.7 %) as the major constituents. The prominent amino acids of RPCs were aspartic acid, 8.7-9.2, glutamic acid, 13.1-13.2, and leucine, 8.5-8.6 g/100 g of protein. Major differences were not observed in each of the amino acid. K, S, Na, and P as minerals were the major elements in RPCs. No difference noted in sodium dodecyl sulfate polyacrylamide gel electrophoresis protein band (15-100 K) possibly representing partial hydrolysis of myosin. Therefore, RPCs from YTR could be use potential protein ingredient for human food and animal feeds.

• Applied Biological Chemistry
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• v.40 no.1
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• pp.71-75
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• 1997

Important physicochemical properties of captafol [N-(1,1,2,2-tetrachloro-ethylthio)cyclohex-4-ene-1,2-dicarboximide], water solubility, vapor pressure, hydrolysis and octanol/water partition coefficient(Kow) were measured based on the standard EPA and OECD methods. Water solubility of the chemical was 2.24 ppm at $25^{\circ}C$. Half-life by hydrolysis at $25^{\circ}C$ in the buffer solution of pH 3.0, pH 7.0, and pH 8.0 was 77.8 hr, 6.54 hr and 0.72 hr, respectively, demonstrating instability in alkaline solution. The half-life in acid condition was not significantly different by temperature change, however, that in neutral or alkaline solution became shorter at $40^{\circ}C$. Hydrolysis study with a reference compound, diazinon, proved that the experimental method of the present study is reliable. Vapor pressure of captafol, $8.27{\times}10^{-9}$ torr at $20^{\circ}C$, was calculated from the equation, log P=6.94-(4401.6/T) plotted on the experiment results under different temperature conditions, 40, 50, and $60^{\circ}C$. pressure of captafol, the contamination of captafol would not happen easily in environment by vaporization. High Kow value of 1,523 was observed and this might result in bioconcentration through food chain when captafol was exposed. However, affecting human health through aquatic bioaccumulation is not likely to occur due to its rapid hydrolysis in the environment.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.152-157
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• 2004

Gluten was extracted from domestic wheat flour using UTH buffer (4 M urea in 0.1 M Tris-HCl, pH 8.6) and validated by SDS-PAGE analysis for production of wheat flour products with reduced gluten content.. Anti-gluten polyclonal antibody was made by administering extracted gluten fraction on animal model. Anti-gluten serum titer of extracted gluten fraction was evaluated by ELISA, and that of antibody titer according to administration period. Anti-gluten sera were used for ELISA and immunoblot analysis before and after hydrolysis of gluten fraction at optimal pH and temperature condition for each protease. Gluten fraction separated by SDS-PAGE showed several bands covering 75 to 10 kDa, in which anti-gluten sera were 25, 34, and 45 kDa. Enzyme hydrolysis of gluten fraction revealed protein band sizes to be lower than 15 kDa. Content of pretense from bovine pancreas (b.p. protease) for gluten hydrolysis was estimated as 1 mg in 10 mL gluten fraction extracted for 4 hr.

• YAKHAK HOEJI
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• v.35 no.4
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• pp.271-276
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• 1991

The extractability and stability of ginkgoflavonolglycosides under presence of several cellulose preparations were investigated. The enzymes used were macerosin, cellulose C and cellulase NC. The content variation of the glycosides was measured with HPLC method, using caffeic acid as an internal standard. The methanol extract of ginkgo leaf, containing the total flavonolglycosides of 4.46%, was used for the content comparison. By extraction with the enzymes, each or mixed, the peak levels of all the glycosides began to decrease after 1 or 2 hours. After 24 hour extraction, most of the glycosides were degraded to minor components. The flavonolglycosides in ginkgo leaf were also hydrolysed simply by the water extraction. After 24 hour extraction with water at $40^{\circ}C$, the peak levels of major glycosides were distinctly decreased. Rutin was hydrolysed by enzyme treatment or by ginkgo leaf itself. As a result, it was concluded that the commercially available cellulases and the ginkgo leaf itself contain the activities of $\beta$-glycosidase and $\alpha$-rhamnosidase. Kaempferol-3-O-(6'"-O-p-coumaroylglucosyl)-rhamnoside and four other ginkgo flavonolglycosides were not hydrolysed under the same condition.tion.

• Fibers and Polymers
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• v.7 no.3
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• pp.241-244
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• 2006

In this paper, the effect of cellulase treatment was evaluated by means of phenol-sulphuric acid method. This method was performed by determining sugar liberation in the treatment bath with the amount expressed in glucose equivalent. As compared with conventional method, the measurement of amount of sugar liberated gave a more reliable and accurate result than the weight loss method. It was found that although the weight loss of cellulose became negligible when the treatment was done under agitation-free condition, the amount of sugar liberated was still readily measurable.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.492-496
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• 2014

In this work, the possibility of Miscanthus as renewable lignocellulosic biomass was evaluated for production of furfural. Also, to find the reaction conditions of furfural production from Miscanthus straw, the effects of solid-to-liquid ratio, reaction temperature, catalyst amount, and reaction time were investigated. Finally, 5.1 g/L furfural was produced from Miscanthus straw in the condition of solid-to-liquid ratio at 1:10, reaction temperature at $150^{\circ}C$, sulfuric acid at 3%, and reaction time of 60 minutes. This result will provide basic knowledge for converting renewable resources into valuable chemicals substituted for fossil fuels.

• Textile Coloration and Finishing
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• v.34 no.3
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• pp.197-206
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• 2022

The purpose of this study was to confirm the optimal spinning conditions for PLA (Polylactic acid) as a fiber forming polymer. According to the melt spinning test results of PLA, the optimal spinning temperature was 258℃. However, it needs to note that relatively high pack pressure was required for spinning at 258℃. At an elevated temperature, 262℃, mono filament was broken easily due to hydrolysis of PLA at a higher temperature. In case of fiber strength, it was confirmed that the draw ratios of 2.7 to 3.3 were optimal for maximum strength of melt spun PLA. Above the draw ratio, 3.3, the strength of the PLA fibers was lowered. It was presumed that cleavage of the PLA polymer chain over maximum elongation. The heat setting temperature of GR (Godet roller) showed that the maximum strength of the PLA fibers was revealed around 100℃. The degree of crystallinity and the strength of the PLA fibers were decreased above 100℃. The optimal take-up speed (Spinning speed) was around 4,000m/min. Thermal analysis of PLA showed 170℃ and 57℃ as Tm (melting temperature) and Tg (glass transition temperature), respectively.

• The Journal of Natural Sciences
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• v.17 no.1
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• pp.13-29
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• 2006

Most redox-active proteins have thiol-bearing cysteine residues that are sensitive to oxidation. Cysteine thiols oxidized to sulfenic acid are generally unstable, either forming a disulfide with a nearby thiol or being further oxidized to a stable sulfinic acid, which have been viewed as an irreversible protein modification. However, recent studies showed that cysteine residues of certain thiol peroxidases (Prxs) undergo reversible oxidation to sulfinic acid and the reduction reaction is catalyzed by sulfiredoxin (Srx1). Specific Cys residues of various other proteins are also oxidized to sulfinic acid ($Cys-So_2H$). Srxl is considered one of the oxidant proteins with a role in signaling through catalytic reduction of oxidative modification like in the reduction of glutathionylation, a post-translational, oxidative modification that occurs on numerous proteins. In this study, the role of sulfiredoxin in cellular processes, was investigated by studying its interaction with other proteins. Through the yeast two-hybrid system (Y2HS) technique, we have found that Ams1 is a potential and novel interacting protein partner of Srxl. $\alpha$-mannosidase (Ams1) is a resident vacuolar hydrolase which aids in recycling macromolecular components of the cell through hydrolysis of terminal, non-reducing $\alpha$-D-mannose residues. It forms an oligomer in the cytoplasm and under nutrient rich condition and is delivered to the vacuole by the Cytoplasm to Vacuole (Cvt) pathway. Aside from the role of Srxl as a catalyst in the reduction of cysteine sulfenic acid groups, it may play a completely new function in the cellular process as indicated by its interaction with Ams1 of the yeast Saccharomyces cerevisiae.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.306-314
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• 2003

Bio-hydrogenation of $C_{18}$-unsaturated fatty acids released from the hydrolysis of dietary lipids in the rumen, in general, occurs rapidly but the range of hydrogenation is quite large, depending on the degree of unsaturation of fatty acids, the configuration of unsaturated fatty acids, microbial type and the experimental condition. Conjugated linoleic acid (CLA) is incompletely hydrogenated products by rumen microorganisms in ruminant animals. It has been shown to have numerous potential benefits for human health and the richest dietary sources of CLA are bovine milk and milk products. The cis-9, trans-11 is the predominant CLA isomer in bovine products and other isomers can be formed with double bonds in positions 8/10, 10/12, or 11/13. The term CLA refers to this whole group of 18 carbon conjugated fatty acids. Alpha-linolenic acid goes through a similar bio-hydrogenation process producing trans-11 $C_{18:1}$ and $C_{18:0}$, but may not appear to produce CLA as an intermediate. Although the CLA has been mostly derived from the dietary $C_{18:2}$ alternative pathway may be existed due to the extreme microbial diversity in the reticulo-rumen. Regardless of the origin of CLA, manipulation of the bio-hydrogenation process remains the key to increasing CLA in milk and beef by dietary means, by increasing rumen production of CLA. Although the effect of oil supplementation on changes in fatty acid composition in milk seems to be clear its effect on beef is still controversial. Thus further studies are required to enrich the CLA in beef under various dietary and feeding conditions.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.226-230
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• 2009

Rice straw was pretreated using dilute sulfuric acid at reaction conditions covering two levels of reaction temperature (140, $150^{\circ}C$) and five levels of acid concentrations ($1.0{\sim}3.0%wt$). The production and decomposition rates of major components of rice straw indicating glucose, xylose, galactose and arabinose were investigated. The production rate of arabinose and the decomposition rate of xylose were greatest among them. The maximum attainable hemicellulose (xylose+galactose+arabinose) yield was about 80%. High acid concentration appears to favor the maximum yield but high temperature does not. The optimum condition was found to be $140^{\circ}C$, 2.5% and 20 minutes. The maximum glucose yields were almost same, around $16{\sim}18%$, regardless of reaction conditions.