• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.14-17
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• 1999

Bovine hide and pig skin gelatins were prepared and their molecular weight profiles were examined by SDS-PAGE. The major molecular weights of bovine hide gelatin were 220 kDa, 140kDa, and 130kDa and the weights of pigskin gelatin were 210 kDa, 135kDa and 120kDa. Also , as a typical parameter of rheological property of the gelatin , viscosities of gelatin were measured under various conditions. Gelatin hydrolysates were prepared using typical commerical proteases and their angiotensin converting enzyme inhibitory activities were examined.

• Journal of Sericultural and Entomological Science
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• v.49 no.2
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• pp.74-76
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• 2007

Antheraea yamamai silk fibroin powder was prepared by treatment with HCl. Amino acid contents of the prepared Antheraea yamamai fibroin hydrolysates were composed of Gly, Ala, Glu, and so on. Biological activities of Antheraea yamamai silk fiborin powder were examined. It is showed about 75% of antioxidation activity compared to the reference ascorbic acid. And it lowered blood glucose level down from 550 mg/dl to 300 mg/dl by serving with wild silk protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.147-153
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• 1995

The cultured mycelial cells of Ganoderma lucidum was extracted by alkali, and then neutralized by acid. The extract was passed through the column of DEAE cellulose for more purification. The neutral fraction was concentrated and precipitated with 95% ethanol. The precipitate was lyophilized and then PSG(polysaccharides) was obtained. PSG was composed of 82.2% polysaccharide, 0.7% protein and 17.1% uronic acid. Sugar conjugates of its hydrolysates were produced using with fluorescent compound(7-amino-1,3-naphthalene disulfonic aicd : 7-AGA), and then fluorescent labeled sugar conjugates were separated by reverse phase high perfomance liquid chromatography. Hydrolysates of PSG were composed of sixteen amino acids and 95.7% glucose, 2.7% xylose, 1.6% fucose and tract amount of galactose and mannose. The immunomodulating effects of PSG on macrophage were perfomed using murine macrophage cell line ATCC TIB 71 cells. PSG augumented the phagocytic activity of TIB 71 cells against fluorescent latex beads.

• Preventive Nutrition and Food Science
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• v.5 no.2
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• pp.65-69
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• 2000

Hen egg-white lysozyme was conjugated with 7~9 mers xyloglucan hydrolysates(MW-1,400) at 6$0^{\circ}C$ and 79% relative humidity for 3 days. SDS-PAGE showed that the conjugation between lysozyme and the oligosaccharide began from 1-day incubation, and three molecules of carbohydrate chains were attached to a protein molecule after 30day incubation. The enzymatic activity of lysozyme was totally conserved in the neoglycoprotein, when measured by using glycol chitin as substrate. Besides, the emulsifying properties of lysozyme were vastly improved by the conjugation with the oligosaccharide, in which emulsifying activity of the neoglycoprotein was five times higher than that of native one.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.221-226
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• 2013

Degrees of hydrolysis by alkaline protease produced from Serratia marcescens S3-R1 is 3.95-6.30% of whey proteins during 5, 15, 30, 60, 90, 120,180, 240 min incubation at $40^{\circ}C$. Proteolytic pattern of the whey proteins showed that various low molecular weight peptides were generated during the incubation periods. The biological function of in Raw 264.7 cells treated with whey protein hydrolytic peptides, anti-inflammatory effect showed exhibit in the expression of pro-inflammatory cytokines such as TNF-${\alpha}$, IL-6, COX-2 and iNOS by PCR analysis. COX-2 and iNOS gene expression inhibited in Raw 264.7 cells on whey protein hydrolysates below 3,000 dalton. The protease from Serratia marcescens S3-R1 showed a potential in production of low molecular weight whey protein hydrolysates which could be used for industrial application.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.480-485
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• 2019

The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.132-138
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• 1998

To improve functional properties and enhance application of FPC in food industry, modified salmon FPC with enzyme treatment was produced and its general properties were investigated. Salmon FPC has over $84\%$ of protein and less than $0.18\%$ of lipid. Solubilities of FPC extracted with IPA and ethanol were very poor as less than $3\%$ in every pH range. In case of enzyme : substrate ratio of 1 : 100, degree of hydrolysis significantly increased until 4 hours and then slightly increased. No considerable differences were observed in general components of hydrolysates. Results of SDS-PAGE showed one unique band in each case and their molecular weight was less than 6,500. The flow properties of hydrolysates showed newtonian flow. Whiteness of hydrolysates were higher than that of salmon FPC as $5\~7$. There was no significant differences in the amount of peptide, but that of free amino acid slightly increased from 0.17 to 0.21 mg/ml.

• Journal of Applied Biological Chemistry
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• v.53 no.3
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• pp.174-178
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• 2010

Calcium and iron binding peptides were prepared by enzymatic hydrolysis and ultrafiltration of rice bran protein (RBP), which was isolated from defatted rice bran by phytase and xylanase treatment and ultrasonication. The isolated RBP had a molecular weight in the range of 10-66 kDa. The extracted proteins were hydrolyzed using Flavourzyme for 6 hr. After ultrafiltration under 5 kDa as molecular weight, the peptides were fractionated into 4 peaks by Sephadex G-15 gel permeation chromatography, and each fraction was determined for calcium and iron binding activity. As the result, Fl and F2 fractions were the best candidate for calcium and iron chelation, respectively. These results suggest that the calcium and iron binding peptides can be used as functional food additives in food industry.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.73-77
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• 1998

The effects of soymilk residues solubilization by cellulase, protease, koji and yeast were investigated on dry matter and protein yields, amino acid and organic acid contents. Co-treatment of soymilk residues by cellulase and protease gave high dry matter yield and protein yield. Koji treatment followed by yeast fermentation was effective for increasing organic acid content and producing soy sauce-like taste and odor. Organic acid content of fermented hydrolysates was improved by cellulase treatment. Protease treatment rather than koji treatment gave high amino acid content, and cellulase treatment seemed to have little effect on increasing free amino acid content. In sensory evaluation, koji-treated hydrolysate showed higher overall acceptance than other hydrolysates, however it showed lower overall acceptance than commercial fermented soy sauce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.4
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• pp.282-292
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• 1987

In order to exploit a new type of food source, enzamatically modified hydrolysates and the plasteins synthesized from the filefish (Nevoden modestus) protein hydrolysates by plastein reaction were investigated. The optimum conditions for enzymatic hydrolysis of filefish muscle and synthesis of plasteins using papain, pepsin, $\alpha-chymotrypsin$ and protease (from Streptomyces griceus) were determined. The optimum temperature and pH for the hydrolysis of filefish muscle by papain, pepsin, $\alpha-chymotrypsin$ and protease were $50^{\circ}C,\;40^{\circ}C,\;55^{\circ}C\;and\;50^{\circ}C$; and 6, 2, 7 and 8, respectively. Those for incubation time and enzyme concentration were 4hr, $0.5\%$ for papain and protease, 24hrs $1.0\%$ for pepsin and $\alpha-chymotrypsin$. The pepsin was found to be more reasonable substrate for plastein synthesis from the economic point of view. The enzyme-induced plastein reaction could be optimized, namely, pH 4 for pepsin, pH 7 for $\alpha-chymotrypsin$, pH 6 for papain and protease: substrate concentration $40\%$ for pepsin, $\alpha-chymotrypsin$ and protease, $50\%$ for papain; the time of incubation, 24hr; enzyme/substrate ratio, 1 : 100(W/V) ; incubation temperature, $50^{\circ}C$.