• The Korean Journal of Mycology
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• v.31 no.2
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• pp.59-66
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• 2003

Laccase produced by Pycnoporus cinnabarinus SCH-3 isolated from Korea was partially purified using ultrafiltration, anion exchange chromatography and affinity chromatography, The laccase was produced as the predominant extracellular phenoloxidase during primary metabolism. Neither lignin peroxidase nor manganese-dependent peroxidase were detected in the culture fluid. In order to examine the effect of inducers in laccase production, 2,5-xylidine was added in the culture of Pycnoporus cinnabarinus SCH-3. Addition of 2,5-xylidine enhanced 25-fold laccase production. Purified laccase was a single polypeptide having a molecular mass of approximately 66 kDa, as determined by SDS-polyacrylamide gel electrophoresis, and carbohydrate content of 9%. $K_{m}\;and\;V_{max}$ values for laccase with ABTS [2,2-azinobis (3-ethylbenzthiazoline 6-sulfonic acid)] as a substrate (Lineweaver-Burk plot) was determined to be $44.4{\mu}M\;and\;56.0{\mu}mole$, respectively. The optimal pH for laccase activity was found to be 3.0. The enzyme was very stable for 1 hour at $60{\circ}C$. Half-life ($t_{1/2}$) of the enzyme was about 10 min at $80{\circ}C$. Spectroscopic analysis of purified enzyme indicated that the enzyme was typical of copper-containing protein. Substrate specificity and inhibitor studies for laccase also indicated to be a typical fungal laccase. The N-terminal amino acid sequence of the P. cinnabarinus SCH-3 laccase showed 94% of homology to the N-terminal sequences of laccases from P. cinnabarinus PB and P. coccineus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.60-66
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• 1986

The muscles of wild and cultured eel, Anguilla japonica, were analyzed for the protein composition and amino acid profile. The differences of the subunit distribution for the sarcoplasmic and myofibrillar proteins were discussed with sodium dodecylsulfate(SDS) polyacryamide gel electrophoresis. The muscle protein in wild eel was composed of $30.78\%$ of sarcoplasmic, $59.02\%$ of myofibrillar, $9.73\%$ of residual intracellular and $2.47\%$ of stroma fraction. That in cultured eel was composed of $31.81\%,\;58.37\%,\;8.16\%\;and\;1.80%$, respectively, The sarcoplasmic and myofibrillar proteins were composed of 16 and 14 subunits in wild eel, and 22 and 15 subunts in cured eel. The sarcoplasmic protein between wild and cultured muscles showed a similar trend in the subunits, except a few subunits such as 36,500, 46,000, 58,500, 75,000, 170,000 and 235,000 daltons in cultured eel. Only the existence of 45,000 dalton subunit was the difference between wild and cultured eel in myofibrillar protein. The distribution patterns of total amino acid in muscles of wild and cultured eel were found to be very similar trend, although glycine content in wild eel was slightly higher than that in cultured one.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.216-222
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• 2014

The purpose of this study was to know the seed longevity of rice (Oryza sativa L.) germplasm for effective viability monitoring. The longevity was determined via germination tests of 3,066 accessions of rice germplasm from the National Agrobiodiversity Center, Rural Development Administration, Korea. The rice germplasm accessions have been conserved at a mid-term storage ($4^{\circ}C$, 30% RH) in plastic bottle containing dehydrated (blue) silica-gel and long-term storage ($-18^{\circ}C$, 35% RH) in hermetically sealed metal can on either sides for 25~26.5 years. The final germination percentages of 3,066 rice germplasm accessions of $6.5{\pm}1.0%$ seed moisture content with 94% initial germination stored at $4^{\circ}C$ for 26.5 years declined to 47% while at $-18^{\circ}C$ for 25 years maintained high germinability as 93%. Germination time courses, which represent the average performance of rice ecotypes stored at $4^{\circ}C$ and 30% RH, were fitted regression equation, to calculate the time at which germination characteristically declined to 50% ($P_{50}$). These $P_{50}$ values of Indica, Japonica, Javanica and Tongil type in rice were 39.9, 22.9, 25.4 and 31.8 years, respectively. The rice germplasm stored at $4^{\circ}C$ could be clustered in 4 groups using quartile of final germination after 26.5 years storage. The seed longevity ($P_{50}$) of each group was estimated by regression equation of changed germination percentages according to storage periods. The $P_{50}$ values of group I, group II, group III and group IV were 21.1, 23.6, 30.0 and 75.7 years.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1209-1215
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• 2003

This study was carried out to establish a quantitative analysis method of separating immuno-activating substance (EN-SP) from Acanthopanax senticosus (A. senticosus) by competitive direct ELISA. Mouse antiserum (anti-EN-SP) against EN-SP was generated by immunization (s.c.) of EN-SP purified from A. senticosus as an immunogen. The titer of anti-EN-SP was about 1 : 400, and the optimal dilution of EN-SP-HRP conjugate was 1 : 1,000. When the standard curve was constructed by ELISA, its sensitivity was about $0.2{\mu}g/mL$. The coefficient variation of intra- and inter-assay were $6.13{\sim}8.81%$ and $6.73{\sim}8.60%$, respectively. According to the standard curve, the concentration of EN-SP in various senticosus extracts was found to be only $59.85\;{\mu}g$ in 10mg of extract from the bark of A. senticosus. Similarly, the immunostimulating activity to produce $TNF-{\alpha}$ or IL-12 among the various extracts of Acanthopanax was shown to be correlated with the content of EN-SP. These results demonstrated that competitive ELISA was a convenient, fast, reproducible, and accurate method for the determination of EN-SP as an immunologically active standard substance in extract of A. senticosus.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.554-560
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• 1991

The physicochemical properties of Korean yam starches (D. aimadoimo, D. batatas and D. japonica) were investigated. The mean granular size of starches were 23.5 μm for D. aimadoimo, 23.9 μm for D. batatas and 18.2 μm for D. japonica. Amylose content, blue value and water binding capacity was $29{\sim}33%,\;0.42{\sim}0.51%\;and\;109.9{\sim}118.3%$, respectively. The optical transmittance of 0.3% (dry basis) yam starch suspensions were increased at $70{\sim}75^{\circ}C$ and D. japonica showed typical two-step transmittance curve. The swelling power and solubility patterns increased over $60^{\circ}C$, and D. aimadoimo was the highest values. Amylogram patterns of 5% (dry basis) yam starch suspensions, determined by Brabender amylograph, were similar to that of yam flours and the viscosity of D. aimadoimo had 630 BU, which was about 5 times higher than 130 BU for D. batatas and D. japonica. Observation under scanning electron microscope lefted marks of resistance to glucoamylase because these surfaces were similar to the natural granules. In rates of solubiliazation by dimethyl sulfoxide, D. aimadoimo showed the highest value. (3-Amylolysis limits of yam starches and their amylose were $71.8%{\sim}75.5%\;and\;90.2{\sim}92.1%$, respectively. Gel filtration patterns of debranched amylopectin by pullulanase were divided into 3 peaks. The weight ratios of peak III to peak II in yam starches were $2.15%{\sim}2.42%$.

• Food Science and Preservation
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• v.23 no.6
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• pp.811-818
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• 2016

The purpose of this study was to investigate changes in the amino acid content and physicochemical properties of Cheonggukjang prepared by using various soybean cultivars (Daewon, Deapung, Seadanbeak, and Taekwang) and a functional microorganism (Bacillus subtilis HJ18-9). These soybeans were conventional Cheonggukjang (control) and Cheonggukjang fermented with Bacillus subtilis HJ18-9 (treated). The moisture contents of steamed, control, and treated soybean were 62.45~67.12%, 63.28~67.14%, and 64.50~66.87%; amino-type nitrogen contents were 6.53~24.25 mg%, 27.63~122.09 mg%, and 37.29~133.48 mg%; and ammonia-type nitrogen contents were 26.92~47.95 mg%, 45.45~156.36 mg%, and 28.02~121.13 mg%, respectively. The umami taste associated with several amino acids (aspartic acid and glutamic acid) in Cheonggukjang was lower than that for steamed soybeans, while the bitter taste from amino acids (methionine, valine, isoleucine, leucine, and phenylalanine) was higher than that for steamed soybeans. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the molecular weight of steamed soybeans was less than 100 kDa, while control and treated groups showed low molecular weights below 34 kDa, confirming their protein hydrolysis to small molecular weight. These results are information for developing functional fermented soybean paste and diversification using soybean cultivars.

• Journal of Life Science
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• v.25 no.7
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• pp.826-832
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• 2015

This study describes the effects of activated charcoal on the removal of salts, detergents, and pigments from protein extracts of ginseng leaves and roots. Incubation of protein extracts with 5% (w/v) activated charcoal (100-400 mesh) for 30 min at 4℃ almost removed the salts and detergents including NP-40 as can be observed on SDS-PAGE. In addition, analysis of chlorophyll content showed significant depletion of chlorophyll (~33%) after activated charcoal treatment, suggesting potential effect of activated charcoal on removal of pigments too along with the salts and detergents. 2-DE analysis of activated charcoal treated protein samples showed better resolution of proteins, further indicating the efficacy of activated charcoal in clearing of protein samples. In case of root proteins, although not major differences were observed on SDS-PAGE, 2-DE gels showed better resolution of spots after charcoal treatment. In addition, both Hierarchical clustering (HCL) and Principle component analysis (PCA) clearly separated acetone sample from rest of the samples. Phenol and AC-phenol samples almost overlapped each other suggesting no major differences between these samples. Overall, these results showed that activated charcoal can be used in a simple manner to remove the salts, detergents and pigments from the protein extracts of various plant tissues.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1265-1273
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• 2005

The purpose of this study was to prepare accelerated salt-fermented anchovy sauce using a shrimp processing byproducts (head, shell and tail) as a fermenting accelerator, and to investigate its physicochemical and enzymatic properties. Four types of sauces were prepared with 0, 10, 20, and 30$\%$ (w/w) addition of shrimp byproduct and fermented at 24$\pm$2$^{\circ}C$ for 360 days. During fermentation, all four type sauces decreased moisture content (67.5$\%$68.0$\%$ to 64.0$\∼$64.8$\%$) and pH (5.52$\∼$7.10 to 5.03$\∼$6.58), but showed increase in their crude protein (7.0$\∼$8.2 to 10.8$\%$) and volatile basic nitrogen contents (40$\∼$75 to 180$\∼$200 mg/100 g of sauce). The ratio of amino nitrogen to total nitrogen contents of control (0$\%$) and sauce with 10$\%$ shrimp byproducts (10$\%$ sauce) were maximized at 270 days, whereas 20$ \% $ and 30$\%$ added sauces were at 180 days. Endoprotease and exoprotease activities of anchovy sauces added with 20$\%$ and 30$\%$ of shrimp byproducts tend to be higher than those of control (0$\%$) and 10$\%$ addition. Proteolytic activities of sauces at pH 9 were about 2 times higher than those at pH 6. Amidolytic activities for LeuPNA decreased remarkably during fermentation, and control (0$\%$) almost lost their activity at 180 days, while additional sauces were relatively stable. These suggest that alkaline pretense of anchovy and shrimp byproducts as a endoprotease mainly contributed to the fermentation of salt-fermented sauces. The protein molecular weight distribution of sauces indicated 2 groups of peaks (peak 1,>70,000 da and peak 2, 3,000$\∼$29,000 da). As the fermentation proceeded, peak 1 tended to decrease in all of sauces, but peak 2 increased rapidly from 30 to 270 days. Optimum fermentation periods of control and 10$\%$ sauces were 270 days and those of 20$\%$ and 30$\%$ sauce were 180 days. The results suggest that shrimp byproduct can be used as accelerator of salt-fermented sauce.

• Food Science and Preservation
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• v.18 no.4
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• pp.604-611
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• 2011

Several wild yeasts were isolated from Korean grape varieties before and during spontaneous fermentation. Among them, four strains were isolated based on the alcohol content and flavor production in wine after fermentation of apple juice. In this study, the four yeast strains were identified and characterized. PCR-restriction fragment length polymorphism analysis of ITS I-5.8S-ITS II region with restriction endonuclease Hae III and Hinf I resulted in that all the strains showed a typical pattern of Saccharomyces cerevisiae. Pulse field gel electrophoresis showed three different chromosome patterns with a same band between strains SS89 and SS812. When ITS I-5.8S-ITS II sequences of the four strains were compared with one another, they were similar to those of Saccharomyces cerevisiae CBS 4054 type strain. Identity of the sequences was higher than 97% with those of the type strain. Phylogenetic analysis showed based on the sequences showed they were genetically closed to the type strain. The four identified strains were tested in a medium containing 200 ppm potassium metabisulfite, and the MM10 and WW108 inhibition rates resulted at up to 24 h. The four strains were tested at an incubation temperature of $30^{\circ}C$. The 30% sugar concentration in the medium (w/v) showed the highest growth in 36 h, especially in the case of SS89, which was close to growth 40. The four strains were tested in an 8% ethanol medium (v/v). Alcohol tolerance was initially kept in the incubation process. The strains began to adapt, however, to the exceeded resistance. The four strains showed the lowest inhibition rate at 24 h.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.119-124
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• 2013

This study was conducted to investigate meat quality and sensory characteristics between castrated and non-castrated dairy goats. Dairy goat of Saanen breeds was slaughtered at an age of 6 mon. Then, characteristics of dairy goat meat were analyzed to chemical compositions, collagen content, pH, meat color, cooking loss, water-holding capacity, shear force, protein solubility, and myofibrillar protein fractions by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Also, odor from dairy goat meats was analyzed by sensory evaluation and volatile substances by gas chromatography-mass spectrometry (GC-MS). As a result, the chemical compositions and physicochemical characteristics were not significantly different between castrated and non-castrated dairy goats meat. Also, there is no difference protein solubility (sarcoplasmic, myofibrillar and total protein) and protein fraction by SDS-PAGE. Sensory evaluation results in odour scores are highly (p<0.05) non-castration dairy goat meat better than castration. As a result, overall palatability was higher (p<0.05) in castrated goat meat when compared with non-castrated one. The indole and octadecanoic acid by GC-MS based on sensory evaluation results were only detected in non-castrated dairy goat meat. Therefore, distribution for goat meats castrated compared to non-castrated dairy goat meat is expected to be able to get a good response to the Korean consumer.