• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.33-40
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• 1978

Immobilization of alkaline protease was investigated by absorbing the enzyme on adsorbents. Alkaline protease was adsorbed on silica gel selected as a carrier to immobilize the enzyme. In this study, properties of the immobilized enzyme were compared with those of the soluble enzyme. 1) The optimum pH (10.0) of the enzyme was not changed, but the activity was increased at alkaline pH by immobilization. 2) The optimum temperature of the immobilized enzyme was shifted from 50$^{\circ}C$ to 45$^{\circ}C$, while the temperature-activity Profile became broader than those of the soluble enzyme. 3) The pH stability of the immobilized enzyme was significantely increased at pH 4.0, althouth it did not change in the neutral and alkaline pH region. 4) The heat stability of the enzyme was enhanced in the temperature range of 55$^{\circ}C$∼65$^{\circ}C$ by the immobilization. 5) The immobilized enzyme retained 40％ of its original activity after repetitive use for 6 times. 6) The enzyme stability was greately improved for a prolonged storage at 4$^{\circ}C$.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.2
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• pp.278-286
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• 2015

The overall purpose of this study was to investigate the effects of Chunggukjang and Greentea-Chunggukjang on the lipid profile, lipid peroxidation and antioxidative enzyme activities of liver tissue in growing male rats fed cholesterol. Twenty seven rats were divided into three treatment groups (Control, Chunggukjang and Greentea-Chunggukjang) and were given experimental diets with 1% cholesterol for 9 weeks. All rats in this study were fed a casein-based diet. Chunggukjang groups were fed diet containing 33.1% Chunggukjang powder. The Chunggukjang and Greentea-Chunggukjang groups showed significantly lower weight gain, food efficiency ratio than the control group regardless of Chunggukjang type. Serum total cholesterol was significantly lower in the Chunggukjang group than in the control group, whereas serum triglyceride and atherogenic index were significantly lower in the Greentea-Chunggukjang group than in the control group. Hepatic triglyceride contents was not significantly different among the diets. However, hepatic cholesterol content was significantly lower in the Greentea-Chunggukjang group than in the control group. Lipid peroxidation of malondialdehyde (MDA) contents was significantly lower in the Chunggukjang and Greentea-Chunggukjang groups than in the control group. Activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) in liver tissue of the Chunggukjang and Greentea-Chunggukjang groups were not significantly different. It can be concluded that Chunggukjang and Greentea-Chunggukjang influence lipid profile and hepatic malondialdehyde contents in growing male rats fed cholesterol.

• Nutrition Research and Practice
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• v.2 no.2
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• pp.62-67
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• 2008

The present study was carried out to evaluate the physiological effects of seaweed supplementation on blood glucose levels, lipid profile, and antioxidant enzyme activities in subjects with type 2 diabetes mellitus. Subjects were randomized into either a control group or a seaweed supplementation group. Pills with equal parts of dry powdered sea tangle and sea mustard were provided to the seaweed supplementation group three times a day for 4 weeks. Total daily consumption of seaweed was 48 g. We found that total dietary fiber intake was 2.5 times higher in subjects receiving seaweed supplementation than in the control group. Accordingly, fasting blood glucose levels (p<0.01) and 2-hour postprandial blood glucose measurements (p<0.05) were decreased significantly in those ingesting seaweed. Furthermore, the serum concentrations of triglycerides were decreased and high-density lipoprotein cholesterol was increased significantly in seaweed supplement group (p<0.05). However, the concentrations of total cholesterol and low-density lipoprotein cholesterol were not affected by seaweed supplementation. The level of thiobarbituric acid reactive substances in erythrocytes was significantly lower with seaweed supplementation compared to controls (p<0.05). Catalase and glutathione peroxidase activities with seaweed supplementation were higher than the controls (p<0.05), but superoxide dismutase activity was not affected. We, therefore, conclude that ingestion of seaweed influences glycemic control, lowers blood lipids, and increases antioxidant enzyme activities.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.6
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• pp.884-888
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• 2003

Proteolytic enzymes are used for meat tenderization, an important process with regard to consumer preference. The proteolytic enzyme, IVRIN was isolated from the plant Cucumis pubescens W and its effect on physico-chemical properties and lipid profile of thigh and breast muscle of culled, desi and broiler birds was studied. Fifty-gram meat was treated with IVRIN containing 32.5 mg enzyme protein at $60^{\circ}C$ for 20 min. The pH of IVRIN treated meat was decreased significantly (p<0.01) and the effect was more pronounced in breast than thigh muscle. The water holding capacity (WHC) was increased significantly (p<0.01) in broiler as compared to desi and culled bird, and in breast compared to thigh muscle. IVRIN failed to produce any impact on muscle fiber diameter (MFD). The MFD of desi was significantly higher (p<0.01) than broiler and culled birds. The total lipid concentration in thigh and breast muscle of desi was lower (p<0.01) than broiler and culled birds, latter being similar in this respect. The cholesterol content was lower (p<0.01) in breast than thigh muscle, in broiler than desi and culled and in IVRIN treated than untreated meat samples. The phospholipid concentration was unaffected by IVRIN. Broiler and culled birds exhibited more phospholipid content than desi birds.

• BMB Reports
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• v.40 no.3
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• pp.315-324
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• 2007

The novel $\alpha$-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of $Ca^{2+}$ and EDTA. Therefore, KRA acts as a $Ca^{2+}$-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of $Ca^{2+}$ and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its Tm. The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis $\alpha$-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the $\alpha$-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.

• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.1-10
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• 2019

The objective of this study was to determine the effect of multi-enzyme supplementation in a corn and soybean meal-based diet on the growth performance, apparent nutrient digestibility, blood profile, fecal microbes and noxious gas emission in growing pigs. A total of 80 crossbred [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] growing pigs with an average body weight (BW) of $25.04{\pm}1.44kg$ were used in a 6-week experiment. The experimental treatments were as follows: CON, basal diet and; T1, basal diet + 100 mg/kg multi-enzyme. During the experiment, the pigs fed the diet with multi-enzyme supplementation had a higher gain to feed ratio (G/F) (p < 0.05) than the pigs fed the diet without multi-enzyme supplementation. On day 42, the pigs fed the diet with multi-enzyme supplementation had decreased $H_2S$ and $NH_3$ emissions (p < 0.05) than the pigs fed the diet without multi-enzyme supplementation. However, no effect was observed on nutrient digestibility, blood profiles and fecal microbes among the treatments (p > 0.05). In conclusion, it is suggested that multi-enzyme supplementation in a corn and soybean meal based diet can partly improve the growth performance and noxious gas emission of growing pigs.

• Journal of Nutrition and Health
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• v.31 no.2
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• pp.135-142
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• 1998

This study was undertaken to determine whether dehulled defatted flour has an effect on postprandial plasma lipoprotein composition, hepatic lipid composition, enzyme and hormone levels in rats. Control(casein) and experimental (dehulled defatted soy flour)diets were fed to rats for 7 weeks. all animals (S. D. rats, male) were sacrificed 2 hrs after the feeding of 5g of each diet. Defatted soy flour feeding significantly lowered postprandial plasma total cholesterol, chylomicron/VLDL-cholesterol, hepatic cholesterol and triglyceride(TG) as compared with casein feeding, whereas no significant effect on plasma TG was observed. Intestinal kipase activity was elevated , whereas trypsin activity was suppressed in the dehulled defatted soy flour group. Plasma glucagon, thyroid hormone and hepatic HMG-coA reductase levels were not affected by diet treatment. These results hypothesize that dehulled defatted soy flour affects cholesterol digestion and absorption in guts, thus delaying the appearance of chylomicron cholesterol in plasma or affecting the disappearance of chylomicron remnant to high-density-lipoprotein(HDL).

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.555-564
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• 2019

Biodiesel is produced through the transesterification process in the presence of alcohol and a catalyst that catalyzes the conversion of triglycerides to esters and glycerol compounds. A more optimal product conversion can be achieved using enzymes, such as lipase. Lipase is reported to be produced in osmophilic yeasts due to the low water content in their natural habitats. Wild forest honey is one of the osmophilic natural habitats in Indonesia. However, lipase-producing yeast has not been reported in the Indonesian honey. In this study, we screened the lipase-producing yeasts isolated from wild forest honey collected from Central Sulawesi. The production profile and activity of lipase were determined at different pH values and temperatures. One promising yeast was isolated from the honey, which was identified as Zygosaccharomyces mellis SG 1.2 based on ITS sequence. The maximum lipase production (24.56 ± 1.30 U/mg biomass) was achieved by culturing the strain in a medium containing 2% olive oil as a carbon source at pH 7 and 30℃ for 40 h. The optimum pH and temperature for lipase activity were 6 and 55℃, respectively. The enzyme maintained 80% of its activity upon incubation at 25℃ for 4 h. However, the enzyme activity decreased by more than 50% upon incubation at 35 and 40℃ for 2 h. This is the first study to report the lipase producing capability of Z. mellis. Further studies are needed to optimize the enzyme production.

• Preventive Nutrition and Food Science
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• v.4 no.4
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• pp.215-220
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• 1999

The Physical properties of corn starch were investigated by scanning electron microscopy, X-ray diffractometry and differential scanning calorimetry during the formation of enzyme-resistant starch(RS). Samples were studied in their native states and after annealing at 50, 55, 60 and 65℃ in excess water(starch : water=1:3) for 48hr. Starch granules became smaller and more rounded after annealing than in their native state. Annealing did not change the X-ray profile of native corn starch. After autoclaving-cooling cycles, native starch lost most of its crystallinity but annealed ones showed some of their crystallinity left as diffuse or poor B-type, which didn't relate to increasing Rs yields. During formation of RS, however, both native and annealed starches changed their X-ray profile from A-type to poor B-type of retrograded amylose. Annealing caused an increase in gelatinization temperature and enthalpy, but a narrowing of gelatinization temperature range. Only starch annealed at 65℃, however, showed a decrease in enthalpy even though its gelatinization temperature increased, which appeared to be due to the partial gelatinization in the amorphous region during annealing. Peak height index(PHI), the ratio of ΔH to Ti-To, increased by annealing. PHI values, therefore, showed the possibility as an indicator to predict RS yield which cannot be differentiated by differential scanning calorimetry and X-ray diffraction data.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.374-379
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• 2003

Four rumen fistulated Murrah buffaloes were used to study the effect of four diets differing in roughage to concentrate ratio on rumen biochemical changes, microbial enzyme profile and in sacco degradability of feed in a $4{\times}4$ Latin Square design. The animals were fed four diets consisting of 80:20, 70:30, 60:40 and 50:50 ratios of wheat straw and concentrate mixtures, respectively. Wheat straw and concentrate mixture were mixed with water (0.6 l/kg feed) and complete feed mixture was offered to the animals at 8:00 h and 16:00 h in two equal parts. The variation in pH of rumen liquor (difference of maximum and minimum during 0-8 h post feeding) increased with increasing level of concentrate mixture in the diet. There was no effect of diet composition on volatile fatty acids, total nitrogen and trichloro-acetic acid precipitable nitrogen in the rumen liquor, but ammonia nitrogen increased with increasing level of concentrate mixture in the ration. Major portions of all fibre degrading enzymes were present in the particulate material (PM) of the rumen contents, but protease was absent in PM fraction. The activities of micro-crystalline cellulase, acetyl esterase and protease increased with increase in the level of concentrate mixture, but the activities of other enzymes (carboxymethylcellulase, filter paper degrading activity, xylanase, $\beta$-glucosidase and $\beta$-xylosidase) were not affected. The in sacco degradability and effective degradability of feeds increased with increasing level of concentrate mixture in the ration.