• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.311-321
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• 2003

Bacteria produce lipases, which can catalyze both the hydrolysis and the synthesis of long chain triglycerides. These reactions usually proceed with high regioselectivity and enantioselectivity, and, therefore, lipases have become very important biocatalysts used in organic chemistry. 3D lipase structures were solved from several bacterial lipases. They have an $\alpha/\beta$ hydrolase fold and a catalytic triad consisting of a nucleophilic serine, and an aspartate or glutamate residue that is hydrogen bonded to a histindine. Active sites are covered with $\alpha$-helical lid structure, of which movement is involved in the enzyme's activation at oil/water interface. Four substrate binding pockets were identified for triglycerides: an oxyanion hole and three pockets accommodating the fatty acids bound at positions sn-1, sn-2, and sn-3. These pockets determine the enantiopreference of a lipase. The understanding of structure-function relationships as well as the development of molecular evolution techniques will enable researchers to tailor new lipases for biotechnological applications.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.249-257
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• 2014

In this study, the anti-oxidative and anti-obesity activities of Amomum cardamomum L. methanol extract (ACME) were evaluated using DPPH radical scavenging activity assay, pancreatic lipase enzyme inhibition assay, and the cell culture model system. ACME exhibited DPPH radical scavenging activities dose-dependently, with $IC_{50}$ of DPPH radical scavenging activities of ACME being $25.15{\mu}g/ml$. Furthermore, ACME effectively suppressed pancreatic lipase enzyme activity dose-dependently. ACME also significantly suppressed adipocyte differentiation, lipid accumulation, triglyceride (TG) contents, and triggered lipolysis activity on 3T3-L1 preadipocytes in a dose-dependent manner, without cytotoxicity. Their anti-obesity effect was modulated by the cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$ and the peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) gene and protein expressions. Taken together, these results provide an important new insight that A. cardamomum L. possesses anti-oxidative and anti-obesity activities such as pancreatic lipase inhibition, anti-adipogenic, and lipolysis effects. There is therefore potential for its use as a promising component in the field of nutraceuticals and the identification of the active compounds that confer the anti-oxidative and anti-obesity activities of ACME might be an appropriate next step.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.813-819
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• 2010

The intracellular lipid droplets were stained with Oil Red O dye and quantified. Compared to the control, lipid accumulation was significantly decreased by 19.4% with the treatment of LCM at the concentration of $1000\;{\mu}g$/mL. Intracellular triglyceride (TG) level was also reduced by 21% at the concentration of $1000\;{\mu}g$/mL. To determine the mechanism for the reduction in TG content, levels of glucose uptake and glycerol release were measured. Incubation of the 3T3-L1 adipocytes with LCM did not affect the cellular uptake of glucose. However, the level of free glycerol released into the cultured medium drastically increased by 24.3% with the treatment of LCM. In subsequent measurements using quantitative real-time PCR, mRNA levels of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) except lipoprotein lipase (LPL) were significantly elevated at higher concentration. These results suggest that LCM partially stimulates the lipolysis through the induction of HSL and/or ATGL gene expression, resulting in the reduced lipid accumulation and increased glycerol release.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.377-382
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• 1991

Reef tallow was hydrolyzed with lipase under the conditions of liquid state and solid state. Lipase OF 360 was used for that purpose, and the lipase had the maximum activity when the olive oil was used as a substrate at pH 6 and $37^{\circ}C$. Beef tallow was dispersed by an agitator to perform a liquid enzymatic reaction. Water content, reaction temperature, and enzyme amount were varied as parameters affecting hydrolysis percentage. Ninety three percents of tallow were hydrolyzed at the following conditions: water content 80% w/w, temperature $37^{\circ}C$, and enzyme amount 200 unitlg tallow. In order to conduct a solid phase enzymatic reaction, sonication was employed for pretreating tallow with the enzyme solution. Molten tallow was sonified with the enzyme solution, and solidified by lowering temperature. And then hydrolysis reaction proceeded at $30^{\circ}C$. Sonication intensity and time were varied to control hydrolysis percentage. Optimum values of the intensity and the time were found to exist since the hydrolysis percentage did not increase further according to the increases of the intensity and the time.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.643-649
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• 2017

Biodegradable enzymes such as lipase and proteinase can hydrolyze not only fatty acid esters and triglycerides, but also aliphatic polyesters. We measured the biodegradability that biodegradable enzymes have an important role in the degradation of natural aliphatic poly material such as PLA, corn starch, and polyethylene glycol in the natural environment. However, we investigated on the biodegradability of PLA, PLA and Polyethylene acrylate blended, and PLAcoPolyethylene polymerized with PLA graft copolymer Polyethylene glycol acrylate. When prepared biodegradable polymers. the Mechanical properties of them were measured on Biodegradability, thermal properties, real time in-situ electrical monitoring of polymers resin. Therefore BOD and biodegradation of PLAcoPolyethylene was graft copolymerized with PLA and polyethylene acrylate were measured at a lower rate than the other samples.

• Microbiology and Biotechnology Letters
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• v.33 no.1
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• pp.24-28
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• 2005

A bacterial strain D­1 found to have potent fibrinolytic activity was isolated from Korean traditional Doenjang. It was identified as Bacillus sp. based on its 16S rRNA sequence analysis, morphological and physiological characteristics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.259-264
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• 2002

In order to develope nutritional and flavoring intermediate products, the optimal processing conditions for two stage enzyme hydrolysate (TSEH) from low-utilized conger eel scrap such as head and intestine were investigated. The optimal processing conditions for TSEH were revealed in temperature at $55^{\circ}C$ 3$\~$4 hours digestion with alcalase at the 1st stage, and 4 hours at $45{\~}50^{\circ}C$ digestion with neutrase at the 2nd stage. Among water extract, steam extract and enzyme hydrolysates of conger eel scrap, the present TSEH was superior to other extracts in terms of yield ana organoleptic taste such as harmonic umami and inhibition of fishy and greasy taste formation. From the results of chemical experiments and sensory evaluation, we may conclude that TSEH of conger eel scrap could be utilized as the flavoring intermediate materials for the fisheries products such as flavoring sauces, drinkable beverage and instant food materials.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.113-119
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• 1984

Initial moisture content and weight of the rice bran and treatment time were identified as important variables for the inactivation of lipase and peroxidase present in rice bran. Multiple regression analysis was used to obtain a prediction equation to measure the effects of moisture content and weight of the sample and microwave treatment time on the residual lipase activity and loss in weight. It was found that the microwave treatment did not affect acid value and extractability of the rice bran oil.

• 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.

• Applied Biological Chemistry
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• v.13 no.1
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• pp.29-34
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• 1970

In order to prepare digested Protein source for the Weanling Food from soybean, an attempt was made to decompose steamed soybean protein to amino acids and peptides by protease and cellulase produced from Aspergillus niger and Aspergillus sojae. In this paper, the optimum condition for digestion of soybean protein were studied and also investigated the effects of decolorization of it. As the results, followings were obtained; 1. As steaming conditions, a treatment under 15 lb of pressure and 10 minutes of heating shows most effective. 2. The optimum pH of Asp, sojae enzyme for the digestion of soybean protein is 6.0, while that of Asp. niger enzyme is 4.4. In successievly-decomposing with Asp. sojae and Asp. niger, it shows the most effective on ratio of water-soluble-nitrogen to total nitrogen and amino-nitrogen to total nitrogen than any other separate treatments. 3. The suitable amount of the enzyme solution to that of the soybean substrate paste, in volume, is 1 : 2. 4. Digestion ratio of soybean protein indicates the gradual and steady effects of increasing time of digestion, but 8 hour-digestion regarding to putrefaction was suitable. 5. The most effective decolorization was successively passed on culumns of active carbon and anion exchanger (Dowex 2-x-8) at room temperature. In separate treatments, the effective order of decolorization was as follows; (Dowex 2-x-8)>Active carborn>Amberite IR-120 6. The powder type of the soy protein source obtained by concentration below $60^{\circ}C$ contains 12.51% of moisture, 66.31% of protein, 4.25% of fat, 12.75% of carbohydrate, 4.18% of ash.