• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.67-73
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• 1999

In order to increase the enzymatic activity of malt used as a source of traditional processing foods, the enzymatic activities of various barley were examined and the effects of ozone and light illumination treatment on the enzymatic activities of amylase, amylase, and glucanase in malt during man ufacture were also examined. Barley didn't show amylase activity prior to soaking, but the activity of barley increased quickly after soaking. Glutinous barley showed the highest amylase activity among Duru barley, Ol barley, two rowed barley and naked barley. Naked barley showed the lowest activity. The amylase activity was the highest in Duru barley and decreased in the order of in glutinous barley, naked barley and two rowed barley. It was showed that the enzymatic activity of malt was higher than that of control when malt was soaked for 24hr at the concentration of 0.3ppm of ozone. The enzymatic activity of malt treated with light illumination was higher than that of control. The bud and root of light illuminated malt was much stronger than that of control. The root of light illuminated malt was much shorter than that of control. In addition, light illuminated malt showed a little green color which matches the demand of consumer. These studies demonstrated that both ozone and light illumination treatment increased the enzymatic activity of malt to result in high quality of malt manufacture.

• Culinary science and hospitality research
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• v.23 no.1
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• pp.95-102
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• 2017

This study was activity of ${\alpha}-amylase$, glucoamylase of liquid Nuruk prepared using liquid Nuruk (NK) and Aspergillus kawachii (AK), Aspergillus niger (AN), Aspergillus oryzae (AO), Monascus kaoliang (MK). To investigate the relationship between the enzymatic activity and the total sugar content of liquid Nuruk depending on the types of Nuruk molds and the degree of rice-polishing. The activity of ${\alpha}-amylase$ depending on the types of Nuruk molds was shown to be 8.82, 8.72 units/mL in AN and AK treatments in brown rice liquid Nuruk at 24 hours after incubation, as the degree of rice-polishing increased, the activity of ${\alpha}-amylase$ was significantly lower (p<0.05). When brown rice was incubated in AN, it showed 8.83 units/mL at 48 hours after incubation, which was the highest activity, but there was no significantly difference (p<0.05), as the degree of rice- polishing was higher, the activity of ${\alpha}-amylase$ was lower. The activity of glucoamylase depending on the degree of rice-polishing showed 3,013 units/mL in AO treatment in brown rice liquid Nuruk at 24 hours after incubation, and the enzymatic activity was significantly higher (p<0.05). As the degree of rice-polishing increased, the activity of glucoamylase decreased, so liquid brown rice Nuruk showed the highest enzymatic activity, liquid white rice Nuruk was the lowest enzymatic activity. The highest enzymatic activity appeared in liquid Nuruk with brown rice at 48 hours after incubation. The activity of ${\alpha}-amylase$, glucoamylase showed higher enzymatic productivity as the degree of rice-polishing was lower, and there was an inverse correlation with the total sugar content.

• Journal of Oral Medicine and Pain
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• v.39 no.4
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• pp.127-132
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• 2014

Purpose: Many substances in saliva or oral health care products interact with each other. The aim of this study was to investigate interactions between hyaluronic acid (HA), lysozyme, peroxidase, and glucose oxidase (GO) in enzymatic activities at low pH levels. Methods: HA (0.5 mg/mL), hen egg-white lysozyme (HEWL, $30{\mu}g/mL$), bovine lactoperoxidase (bLPO, $25{\mu}g/mL$), and GO ($50{\mu}g/mL$) were used. The influences of HA, bLPO, and GO on HEWL activity were determined by measuring the turbidity of a Micrococcus lysodeikticus suspension. The influences of HA and HEWL on bLPO activity were determined by the NbsSCN assay, measuring the rate of oxidation of 5-thio-2-nitrobenzoic acid (Nbs) to 5,5'-dithiobis(2-nitrobenzoic acid) $(Nbs)_2$. The influences of HA and HEWL on GO activity were determined by measuring oxidized o-dianisidine production. All experiments were performed at pH 4, 5, and 6. Results: HA and GO did not affect the enzymatic activity of HEWL at pH 4, 5, and 6. bLPO enhanced the enzymatic activity of HEWL at pH 5 (p<0.05) and pH 6 (p<0.05) significantly. The enzymatic activity of bLPO was not affected by HA and HEWL at pH 4, 5, and 6. HA and HEWL did not affect the enzymatic activity of the GO at pH 4, 5, and 6. Conclusions: Peroxidase enhances lysozyme activity at low pH, otherwise there were no significant interactions in enzymatic activities between HA, lysozyme, peroxidase, and GO at low pH levels.

• YAKHAK HOEJI
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• v.5 no.1
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• pp.45-50
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• 1960

Some enzymatic properties of Cynthia roretzi v. (Drasche Korean : U-Rung-Shei) was studied by author and obtained the following results; 1. The optimum pH of the digestive gland amylase was 6.8-7.0 2. Activity of metallic ion on the amylase showed the following order; 10$^{-3}$ M M $n^{++}$>10$^{-3}$ M $Co^{++}$>10$^{-4}$ M $Mg^{++}$>10$^{-4}$ M $Ca^{++}$>10$^{-2}$ M Z $n^{++}$>10$^{-2}$ M P $b^{++}$ 3. The digestive gland enzyme inactivated at 70.deg. C. 4. When the enzyme concentration increase 2 times, the enzymatic activity also increase, but not propertionally. 5. The digestine gland amylase showed remarkably higher enzymatic activity than the intestinal amylase. 6. The digestive gland amylase from the ascidian showed remarkably higher enzymatic activity than the heptancreatic amylase from shell fish (Turbo (Batillus) Cornutus Solander).nder).nder).

• YAKHAK HOEJI
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• v.4 no.1
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• pp.35-38
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• 1959

The enzymatic activity of amylase which was isolated from a shell fish Veneridae Soxidmnus purpuratus Sowerby(Korean name :Gai-jo-gai") was studied and the obtained results were as follows: (1) The optimum pH of the enzyme was Ca. 6.2-6.4. (2) Prohibiting activity of metalic ions for the enzymatic activity was the order of 1/1000M-$Mg^{++}$>1/1000M-$Sr^{++}$>1/1000M-$Na^{+}$, and $Ca^{++}$ ion's prohibiting action was hardly showed. (3) Of 3 specimens of amyiase from Heptapancreas, Gastro-intestine and crystalline style, the highest activity was shown by amylase from crystlline style, and the other two showed almost same degree of activity. (4) Heptapancreas Amylase from the shell fish showed remarkably higher enzymatic activity than the pancreas amylase from a pig.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.569-575
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• 2018

Objective: This experiment was conducted to investigate the effects of chromium picolinate (CrP) on fat deposition, genetic expression and enzymatic activity of lipid metabolism-related enzymes. Methods: Two hundred forty one-day-old Ross broilers were randomly divided into 5 groups with 4 replicates per group and 12 Ross broiler chicks per replicate. The normal control group was fed a basal diet, and the other groups fed the same basal diet supplemented with 0.1, 0.2, 0.4, and 0.8 mg/kg CrP respectively. The experiment lasted for 21 days. Results: Added CrP in the basal diet decreased the abdominal fat, had no effects on subcutaneous fat thickness and inter-muscular fat width; 0.2 mg/kg CrP significantly decreased the fatty acid synthase (FAS) enzymatic (p<0.05); acetyl-CoA carboxylase (ACC) enzymatic activity decreased in all CrP groups (p<0.05); hormone-sensitive lipase (HSL) enzymatic activity also decreased, but the change was not significant (p>0.05); 0.4 mg/kg CrP group significantly decreased the lipoprotein lipase (LPL) enzymatic activity. FAS mRNA expression increased in all experimental groups, and the LPL mRNA expression significantly increased in all experimental groups (p<0.05), but not 0.2 mg/kg CrP group. Conclusion: The results indicated that adding CrP in basal diet decreased the abdominal fat percentage, had no effects on subcutaneous fat thickness and inter-muscular fat width, decreased the enzymatic activity of FAS, ACC, LPL and HSL and increased the genetic expression levels of FAS and LPL.

• Korean Journal of Microbiology
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• v.9 no.4
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• pp.155-162
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• 1971

A comparison of dextrinogenic amylase activities in the Asp. niger group was made with their crude and ethanol dialized enzymes before and after heating at high temperature (60-$65^{\circ}C$). The results obtained are as follows ; 1. THe dextrinogenic amylase activity of crude enzymes of Asp. kawachii and Asp. foetidus was strong, but Asp. phoernicis, Asp. carbonarius and Asp.japonicus showed weak activity. The others showed medial grades of activity. 2. The ethanol dialized enzymes of Asp. kawachii, Asp. foetidus and Asp. japonicus was very sesitive to high temperature (60 or $65^{\circ}C$) and their enzymatic activities were diminished greatly. The others did not show diminution of enzymatic activity at 60 or 65.deg.C, but diminished greatly at 70 or $75^{\circ}C$. 3. The ethanol dialized enzymes of the Asp.niger group heated to 65.deg.C was more sensitive at pH 6.0 and 6.5 than at pH 4.5, 5.0 and 5.5. 4. Tested strains in the Asp.niger group were subdivided into 4 subgroups by their dextrinogenic amylase activities before and after heating at 60 or $65^{\circ}C$. The first group showed a medial grade of activity before heating and no diminution of their enzymatic activities after heating. Asp. niger, Asp.pulverulentus, Asp. awamori and Asp. usmii were included in this group. The second group had strong enzymatic activity before heating, but diminished greatly after heating. Asp rawachii and Asp. phoenicis were included in this group. The fourth group showed very weak enzymatic activity before heating, and was inactivated easily by heating. Asp.oryzae of the Asp. flavus group showed a very strong dextrinogenic amylase activity before heating. After the heat treatment, however, its enzymatic activity was diminished greatly.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.365-368
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• 1998

The aklavinone 11-hydroxylase which was overexpressed using T7 promoter in E. coli could be detected in SDS-PAGE only in insoluble precipitate without any detectable enzyme activity. The insoluble enzyme was solubilized in 6M guanidine$.$HCl solution and their refolding ability was tested under various conditions. When the enzymatic activity was checked by the bioconversion experiment, stepwise dialysis against 6M, 3M, 1M guanidine$.$HCl and finally 100 mM potassium phosphate buffer of the solubilized protein gave the best bioconversion efficiency. The aklavinone 11-hydroxylase showed its enzymatic activity in the reaction buffer containing NADPH with vigorous shaking. The enzymatic activity was lost during partial purification and regained by the addition of crude extract of S. lividans in the reaction mixture. This effect was confirmed to due to some low-molecular weight component(s) in the crude extract, because the addition of dialyzed crude extract could not recover the enzymatic activity.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.21-28
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• 2009

In this study, we focused on natural water-soluble antioxidants from Tetraselmis suecica (T. suecica) and Chlorella ellipsoidea (C. ellipsoidea). They were prepared by enzymatic digestion using five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and five proteases (Protamex, Alcalase, Flavourzyme, Neutrase, and Kojizyme), and the potential antioxidant activity of each was assessed. Most enzymatic digests from T. suecica had a higher radical scavenging activity than those from C. ellipsoidea. Among the enzymatic digests, Kojizyme digest from T. suecica exhibited the highest effect on DPPH radical scavenging. Viscozyme (30.2%) and Neutrase (34.6%) digests from T. suecica exhibited higher hydroxyl radical scavenging activity. Kojizyme digest from T. suecica (81.5%) had strong alkyl radical scavenging activity. Neutrase (61.9%) and Kojizyme (61.5%) digest from T. suecica possessed the highest effects on hydrogen peroxide scavenging. Among the tested samples, Neutrase (TN) and Kojizyme (TK) digests from T. suecica showed the highest antioxidant activity (DPPH, alkyl radical, hydrogen peroxide). Therefore, TN and TK digests were selected for use in the further experiments. Those digests showed enhanced cell viability against $H_2O_2$-induced oxidative damage, and relatively good hydrogen peroxide scavenging activity in an African green monkey kidney (Vero) cell line. These results suggested that an enzymatic digestion will be an effective way for the production of a potential water-soluble antioxidant from a microalgae, T. suecica.

• Preventive Nutrition and Food Science
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• v.21 no.4
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• pp.338-347
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• 2016

The present study investigated the volatile compound, physicochemical, and antioxidant properties of beany flavor-removed soy protein isolate (SPI) hydrolyzates produced by combined high temperature pre-treatment and enzymatic hydrolysis. Without remarkable changes in amino acid composition, reductions of residual lipoxygenase activity and beany flavor-causing volatile compounds such as hexanol, hexanal, and pentanol in SPI were observed after combined heating and enzymatic treatments. The degree of hydrolysis, emulsion capacity and stability, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, and superoxide radical scavenging activity of SPI were significantly increased, but the magnitudes of apparent viscosity, consistency index, and dynamic moduli (G', G") of SPI were significantly decreased after the combined heating and enzymatic treatments. Based on these results, it was suggested that the enzymatic hydrolysis in combination with high temperature pre-treatment may allow for the production of beany flavor-removed SPI hydrolyzates with superior emulsifying and antioxidant functionalities.