• Food Science of Animal Resources
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• v.33 no.4
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• pp.542-548
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• 2013

This study was conducted to investigate effect of psychrotrophic bacteria on the quality of raw milk. Acinetobacter genomospecies 10 was selected as lipolytic species, and Serratia liquefaciens as proteolytic species. Lipase present in inoculated raw milk with Acinetobacter genomospecies 10 did not affect total solid and fat contents. However, the free fatty acid (FFA) content, especially short chain FFAs, of milk with Acinetobacter genomospecies 10 was dramatically increased. FFAs produced by lipolysis of milk fat are important in flavor of dairy products, excessive lipolysis occurring in milk and dairy products could cause off-flavor, and produced FFAs may have an underiable effect on their flavor. In addition, protease influenced the quality of inoculated raw milk with Serratia liquefaciens. In degradation patterns of casein by SDS-PAGE analysis from inoculatred raw milk with Serratia liquefaciens, casein content was gradually decreased during storage at $4^{\circ}C$, and extensive degradation of $\kappa$-casein was observed on the storage day of 13. The free amino acids such as leucine, valine, arginine, and tyrosine were dramatically increased, which causes bitter taste in raw milk. These excessive peptides in dairy products, produced by psychrotrophic bacteria, can be possible to develop off-flavors and be responsible for gelling of milk by degradation.

• KSBB Journal
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• v.15 no.1
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• pp.72-75
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• 2000

The hydrolysis characteristics of each fatty acid composing the fish oil by means of the lipase from Candida cylindracea was investigated. The saturated fatty acids, C14:0, C16:0 and C18:0, and the unsaturated fatty acids with one double bond, C16:1, C18:1(n-7), C18:(n-9), C20:1 and C22:1 were more easily hydrolyzed than the $\omega$-3 polyunsaturated fatty acids. when the number of carbon of the $\omega$-3 fatty acids was same but that of double bond was different, the hydrolysis of the $\omega$-3 fatty acids having lower number of double bond was more rapidly carried out. When the degree of polyunsaturation was same but the number of carbon was different, the lipase acted more rapidly upon the $\omega$-3 fatty acids with lower number of carbon. Docosahexaenoic acid(DHA) was most highly concentrated in the glyceride mixture after 120hr hydrolysis among the various $\omega$-3 polyunsaturated fatty acids. The weight percentage of DHA to the $\omega$-3 fatty acids in the fish oil was 31.87% but that in the glyceride mixture after 120hr hydrolysis was 51.89%.

• Journal of Life Science
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• v.25 no.12
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• pp.1393-1398
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• 2015

In this study, we investigated the extraction condition of alginate from Laminaria japonica, the enzymatic degradation of the extracted alginate, and the inhibitory activity of the degraded alginate on the differentiation of 3T3-L1 preadipocytes. The optimal conditions for the efficient extraction, precipitation, and recovery of alginate from the brown seaweed L. japonica were 1% for Na₂CO₃ concentration, 80℃ for extraction temperature, and ethanol for precipitation solvent. In the enzymatic reaction for the production of low-molecular-weight alginate (LMWA) by using alginate lyase from Flavobacterium sp., the initial concentration of Laminaria alginate was 3%. The low-molecular-weight degree from alginate was independent with the enzyme concentration, and the optimal concentration of alginate lyase was found to be 5 unit/ml. Through the enzymatic reaction with 5 unit/ml of alginate lyase at 37℃ for 3 hr, the viscosity and molecular weight of LMWA were 4.5 cp and 307 kDa, respectively. Treatment with LMWA significantly suppressed the accumulation of lipid droplet and triglyceride in 3T3-L1 preadipocytes with a dose-dependent manner. Therefore, it seems that LMWA treatment could inhibit the differentiation of 3T3-L1 preadipocytes. These results indicate that LMWA or the degraded alginate produced by alginate lyase enzyme can be useful for the development of anti-obesity biosubstances.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1353-1358
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• 2004

This study was conducted to increase crude protein and reducing sugar contents in pollen extracts by proteases. Four commercial neutral proteases (Alcalase 2.4L, Protamex, Flavozyme and Protease A) and two alkaline proteases (Protease S and Protease P) were used to prepare acorn and Darae pollen extracts. Contents of moisture, ash, crude protein and crude fat of acorn pollen were 5.2%, 2.7%, 6.2% and 22.3%, respectively, while those of Darae pollen were 5.4%, 2.8%, 1.8% and 27.8%, respectively. Contents of crude protein and reducing sugar in pollen extracts were increased by proteases. Alcalase 2.4L was the most effective in increasing protein contents while Protease A in increasing reducing sugar contents. It is suggested the use of proteases is one of the potential methods for increasing the contents of crude protein and reducing sugar in preparation of pollen extracts.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.49-58
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• 2006

This study was conducted to evaluate effects of mud flat bacteria origin protease supplementation on growth performance, amino acid digestibility, blood characteristics, meat quality, fecal VFA (volatile fatty acids) and NH3-N (ammonia nitrogen) concentration in finishing pigs. Eighty pigs (Landrace×Yorkshire×Duroc, 60.08±2.69 kg average initial body weight) were used during experimental period. Dietary treatments included 1) high nutrient density diet, 2) high nutrient density diet+0.1% protease, 3) low nutrient density diet and 4) low nutrient density diet+0.1% protease. For overall period, ADG was improved in treatment of high nutrient density diet added protease compared with treatment of low nutrient density diet without protease (P<0.05). DM and N digestibilities were improved in treatments of high nutrient density diet and low nutrient density diet added protease compared with treatment of low nutrient density diet without protease (P<0.05). Essential amino acid digestibility was improved in treatment of low nutrient density diet added protease compared with other treatments (P<0.05). Nonessential amino acid digestibility was improved in treatment of high nutrient density diet added protease compared with treatments of high and low nutrient density diet (P<0.05). BUN (blood urea nitrogen)　concentration in blood was increased in treatment of high nutrient density diet added protease compared with treatment of low nutrient density diet without protease (P<0.05). L*value of M. longissimus dorsi muscle was increased in treatments of low nutrient density diet compared with treatments of high nutrient density diet (P<0.05). In conclusion, mud flat bacteria origin protease was effective for improving growth performance, amino acid digestibility and influencing BUN concentration and meat color in finishing pigs.

• Journal of Convergence for Information Technology
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• v.12 no.3
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• pp.126-131
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• 2022

Obesity is known as a metabolic disease caused by abnormal differentiation of fat tissue due to an imbalance between energy intake and consumption.. The purpose of this study was to confirm the changes in the genes associated with pancreatic lipase activity and pre-adipocyte cell differentiation by treatment of red onion extract treatment. The effect of red onion extract treatment on pre-adipocyte differentiation was evaluated using 3T3-L1 adipocytes, and the activity of related genes was confirmed through Real-Time PCR. As a result of the experiment, the red onion extract inhibit pancreatic lipidase activity by concentration dependent manner. In addition, it was found to inhibit adipocyte differentiation and inhibit the activity of genes(C/EBP-α, C/EBP-β, PPAR-γ) associated with adipocyte differentiation. Through the results of this experiment, it is suggested that the red onion extract can be developed as a high potential material with anti-obesity efficacy by suppressing adipocytic differentiation by controlling genes related to adipocyte differentiation.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.129-138
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• 2016

Eicosanoids are a group of C20 oxygenated polyunsaturated fatty acids (PUFAs). To monitor biosynthetic precursors of these PUFAs, this study extracted fatty acids from different tissues of the beet armyworm, Spodoptera exigua, and assessed their compositions using GC/MS. Fifth instar larvae were dissected to isolate different tissues of gut, fat body, hemocytes, and integument. From each tissue, total lipids were extracted and fractionated into neutral lipid (NL), glycolipid (GL), and phospholipid (PL). Most tissues contained palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), and linolenic acid (18:3). However, their compositions were different among tissues and lipid types. Fat body and hemocytes possessed other type of fatty acids such as myristic acid (14:0) and three unknown fatty acids. Among lipid types, PL contained relatively high levels of linolenic acid than NL and GL, while it had lower saturated fatty acids. Total unsaturated fatty acid composition was varied among tissues and lipid types. PL was rich in unsaturated fatty acids in fat body, gut, and hemocytes. There was a significant influence of calcium-independent phospholipase $A_2$ ($iPLA_2$) on maintaining fatty acid composition because RNA interference of $iPLA_2$ expression significantly modified fatty acid compositions in NL and PL. However, this study did not detect arachidonic acid, a main eicosanoid biosynthesis precursor, in all tissues. This suggests an alternative biosynthesis of eicosanoids in insects, which is distinct from the biosynthetic pathway of mammals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.791-798
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• 1998

To develop natural flavoring substances. optimal hydrolysis conditions for two stage enzyme hydrolysates (TSEH) using low-utilized shellfishes such as purplish clam and frozen oyster stored at $-20^{\circ}C$ for 60 days. The optimal conditions for TSEH method were revealed in temperature at $50^{\circ}C$ 3 hours digestion with alcalase (Aroase AP-10, $0.3%$ w/v, pH 8.0) at the 1st stage and $45^{\circ}C$ 2 hours digestion with neutrase (Pandidase NP-2, $0.3\%$ w/v, pH 6.0) at the 2nd stage. Among water extracts, autolytic extracts and 4 kinds of enzyme hydrolysates tests, TSEH method was superior to other methods on the aspect of yields, nitrogen contents, taste such as umami and control of off-flayer formation, and transparency of extracts. From the results of chemical experiments and sensory evaluation, we may conclude that TSEH from low-utilized marine products is more flavorable compared the conventional enzyme hydrolysates, it could be commercialized as the seasoning substances.

• Food Science and Preservation
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• v.10 no.2
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• pp.192-199
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• 2003

To prepare soybean curd utilizing effectively bioactive component of soybean, ultra fine whole soybean flour(UFWSF) was used as a soybean curd material for preparation of uncompressed whole soybean flour curd(UWSFC) in this study. The UWSFC was made with treatment by proteinase and coagulant, and proximate composition, color, textural properties and sensory evaluation of that were analyzed. Protease produced from Aspergillus sojae, bromelain and papain showed soybean curd coagulation ability and the pretense produced from Aspergillus sojae showed the highest soybean curd coagulation ability. When, after first heating and homogenizing, the proteinase was added to soybean milt textural properties of UWSFC were the best. Hunter's L and b values and textural properties (hardness, fracturability springiness, gumminess and chewiness) of UWSFC using proteinase and coagulant were higher than commercial soft soybean curd and adhesiveness and cohesiveness showed contrary tendency.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1688-1694
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• 2014

Jeju Hallabong Tangor (Citrus kiyomi${\times}$ponkan) is a Citrus species with a variety of physiological properties such as anti-oxidant, anti-inflammation, anti-cancer, and anti-obesity. We investigated the anti-obesity effects of Hallabong Tangor peel extracts before (HLB) and after (HLB-C) bioconversion with cytolase based on modulation of adipocyte differentiation and lipid metabolism in 3T3-L1 adipocytes. Treatment with cytolase decreased flavanone rutinoside forms (narirutin and hesperidin) and increased flavanone aglycone forms (naringenin and hesperetin). During adipocyte differentiation, 3T3-L1 cells were treated with 0.5 mg/mL of Sinetrol (a positive control), HLB or HLB-C. Adipocyte differentiation was inhibited in both citrus groups, but not in control and Sinetriol groups. HLB and HLB-C tended to reduce insulin-induced mRNA levels of CCAAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$) and sterol regulatory element-binding protein 1c (SREBP1c). Compared to the control and Sinetrol groups, HLB and HLB-C markedly suppressed insulin-induced protein expression of $C/EBP{\alpha}$ and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$). The HLB and Sinetrol groups, but not HLB-C group, significantly increased adipolytic activity with higher release of free glycerol compared to the control group in differentiated 3T3-L1 adipocytes. These results suggest that bio-conversion of Hallabong Tangor peel extracts with cytolase increases aglycone flavonoids. Irrespective of bioconversion, both Hallabong Tangor peel extracts exert anti-obesity effects that may contribute to prevention of obesity through inhibition of adipocyte differentiation or induction of adipolytic activity.