• Applied Biological Chemistry
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• v.28 no.2
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• pp.88-91
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• 1985

For the systematic investigation of biochemical characteristics of Korean ginseng protein, protein fractions were analyzed by the techniques of sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The effect of pH and various salts on extractibility of ginseng protein were determined while the amino acid composition was studied by amino acid autoanalyzer. The protein was consisted of 66.08% of albumin and 20.51% of glutelin. Extractability of ginseng protein was the lowest in pH 3.0 and the highest in $pH\;6.0{\sim}8.0$. Among the neutral salts solution, $0.4M\;Na_2CO_3$ showed maximum extractability while $1.0M\;MgSO_4$ solution showed the least extractability. Resonable precipitation was obtained by 40% of acetone and ammonium sulfate. It has been shown by SDS polyacrylamide gel electrophoresis that the soluble protein had 11 bands. The molecular weight for the main protein of the soluble protein wasestimated to be 43,000. In amino acid composition of water extracted protein, arginine content was the highest 47.17% while on the contray, proline and cystine contents were very low.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.381-387
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• 1991

Andong Sickhae is a traditional Korean fermented rice product which is made from glutionous rice, male, radish, ginger and red pepper. The changes in chemical composition, pH, amino nitrogen, amino acid, enzyme activity and free sugar of a traditional Andong Sickhae were monitored during the fermentation and storage at $4^{\circ}C$. The changes in ash, crude fat and moisture the contents during Andong Sickhae fermentation and storage were negligible. The pH of the product tended to decrease in the course of fermentation and storage and it showed the minimum value of 3.90 after 20th day of storage. On the other hand the maltose continued to increase up from 6.35g to 9.85g/100ml by 15th day of storage. The content of amino nitrogen in Andong Sickhae gradualy increase up to 22.40mg% by 3th day of fermentation. Glutamic aicd and aspartic acid were the major amino acid in water and salt soluble protein in Andong Sickhae.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.119-123
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• 2003

From the 80% ethanol extraction of onion flesh, fraction I,II and III were separated by Sephadex LH-20 column chromatography. Fraction II and III had a high inhibitory effect on ACE and xanthine oxidase. The ACE was about 80% at 50 ppm of fraction IIand III. The xanthine oxidase was about 82.5% at 100 ppm of fraction In. This research was studied to investigate the effects of the fraction In isolated from onion on the reduction of fat accumulation in rats fed high fat diet for 2 months. The metabolism was examined by analyzing the fat in serum and liver. It was shown that cholesterol in serum was remarkably reduced in onion fraction In as compared with those of control.

• Journal of the Korean Chemical Society
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• v.21 no.6
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• pp.445-448
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• 1977

This study was carried out to understand the activity of ${\alpha}$-chymotrypsin, a proteolytic enzyme, to a oligopeptide in the presence of various coloring food additives. 1. The melting point of synthetic oligopeptide, Asp-Arg-Val-Tyr-Ile-His-Pro-D-Ala, ((8-D-Ala) angiotensin Ⅱ) was 210∼$212^{\circ}C$. Chemical formula and molecular weight were $C_{44}H_{67}N_{13}O_{12}{\cdot}2CH_3COOH{\cdot}H_2O$ and 970.08, respectively. 2.The amino acid rations by acid hydrolysis were Asp : 1.01, Arg : 1.03, Val : 1.00, Tyr :40.94, Ile : 1.00, His : 1.05, Pro : 1.04, D-Ala : 1.03. 3. ${\alpha}$-Chymotrypsin cleaved the oligopeptide bond between tyrosine and isoleucine (Tyr-Ile). 4. The addition of food coloring additives as determined by paper chromatogram, did not influence the inhibitory activity of ${\alpha}$-chymotrypsin on oligopeptide, (8-D-Ala) angiotensin II.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.348-355
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• 1989

This experiment was conducted to investigate the characteristics of alkaline protease from Aspergillus fumigatus which was isolated from soil as a superior strain for the production of the alkaline protease. The optimum temperature for enzyme activity was $50^{\circ}C$ and optimum pH was 9.0. The enzyme was stable at pH 8.0 to 10.0 and thermal inactivation was shown $30^{\circ}C$. The activity of the enzyme was increased by the addition of $Mn^{++},\;Cu^{++},\;Ba^{++},\;Mg^{++},\;$wheras it was inhibitied by $K^+,\;Fe^{+++},\;Ag^+,\;Pb^{++},\;Na^+,\;Ca^{++},\;Hg^+,\;Zn^{++}$. EDTA. 2, 4-DNP, ${\varepsilon}-amino$ caproic acid did not show inhibitory effect on the proteolytic activity of alkaline protease but P-chloromercuribenzoic acid inhibited the enzyme activity, indicating that reactive sulfhydryl group is required for the enzymatic activity. The reaction of this enzyme followed typical Michael-Menten Kinetics with the Km value of $8.33{\times}10^{-4}mole/{\ell}$ with the Vmax of $47.62{\mu}g/min$. This enzyme had stronger proteolytic activity than trypsin on substrate such as casin and hemoglibin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.2
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• pp.152-157
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• 1986

Changes in protein, amino acids composition and protein activity of native Meju were investigated at various time intervals over 6 weeks of fermentation by using, gel filtration, and amino acid analyzer. From the quantitative fractionation of native Meju proteins, albumin content (36.4%) was the highest at 4 weeks. During Meju fermentation, albumin increased gradually but glutelin decreased up to 4 weeks. Globulin and prolamin content did not change substantiantiall. When albumin was fractionated by Sephadex G-200, two main peaks were fractionated and a new peak appeared after 4 weeks. Its molecular weight was extimated to be 66,000 by the gel filtration method. Amino acid composition of albumin in native Meju appeared to be 17 kinds. Glutamic acid content (87.98-317.10) were the highest, followed by aspartic acid and glycine. The proleolytic enzyme activity increased when the native Meju was fermented and marked the maximum value at 4 week.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1388-1393
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• 1998

Traditional Andong sikhe was produced by fermenting L. bulgaricus LBS 47 and S. cerevisiae SCS 5. The changes of nitrogen compound and amino acid during fermentation and storage were investigated. Crude protein was increased until 4days, the main fermentation period. Amino form nitrogen increased up to 37.50 mg% at the 2nd day of fermentation and the product tasted best at this time. Water soluble and salt soluble protein decreased during fermentation. Proline and aspartic acid were the two major free amino acids. The free methionine increased while the free lysine decreased in the process of fermentation. The amino acids of water soluble protein and salt soluble protin were totally 17 kinds. The major amino acids of water soluble and salt soluble protein were glutamic acid and aspartic acid. The arginine content of salt soluble protein increased as the fermentation proceeded.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.187-194
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• 1992

Rhizopus oryzae CJ-2114 was selected for its strong polygalacturonase activity among various strains of mold found in soil. It was found that the production of polygalacturonase reached to maximum when the wheat bran medium containing 1% albumin, 1% sorbitol and 0.2% (NH$_4$)$_2$C$_2$O$_4$was cultured for 96 hrs at 3$0^{\circ}C$. Polygalacturonase was purified 11.13 fold from Rhizopus oryzae CJ-2114. The purification procedures include ammonium sulfate treatment, gel filtration on Sephadex G-75, G-150 and DEAE-cellulose ion exchange chromatography. Yield of the enzyme purification was 40.3% .Purified enzyme was confirmed as a single band by the polyacrylamide gel electrophoresis. When the purified enzyme was applied to SDS-poly-acrylamide gel electrophoresis, the molecular weight was estimated to be 47,000. The amino acid composition indicated relatively high contents of glutamic acid and glyrine.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1394-1398
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• 1998

Lactobacillus bulgaricus LBS 47 and Saccharomyces serevisiae SCS 5 were selected for pure culture inoculation in the fermentation. The effects of stabilizers on the sedimentation, sensory evaluation and viscosity were investigated during fermentation of traditional Andong sikhe. Among the stabilizers added to the traditional Andong sikhe the Na-alginate appeared to be the best. When the product was evaluated by the sensory panel, the addition of stabilizers up to 0.1 % level actually increased the acceptability of the product, while the concentration of more than 0.2% stabilizers affected the acceptability negatively. The viscosity of the product fermented with the CMC and Na-alginate addition reached the maximum on the 2nd day of fermentation, while that of the homogenized Andong sikhe fermented with carrageenan reached the peak on the first day of fermentation.

• Applied Biological Chemistry
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• v.37 no.5
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• pp.356-360
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• 1994

The optimum pH and temperature for endo-polygalacturonase activity from Jujube were 5.0 and $50^{\circ}C$. The range of its stability to pH was 4.0 to 5.0. The enzyme was inactivated about 35% by treatment at $70^{\circ}C$ for 1 hr. It was found that $Ag^+$, $Zn^{++}$ and $Mg^{++}$ increased the enzyme activity. In contrast, $Ba^{++}$, $Hg^{++}$, $Pb^{++}$, $Ca^{++}$, $Mn^{++}$, $Cu^{++}$, $Fe^{+++}$, $Na^+$ and $K^+$ decreased it. The enzyme was inactivated by treatment with maleic anhydride, iodine and 2,4-dinitrophenol. The results indicate that active site is a imidazole group on the enzyme.