• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.601-603
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• 2000

Enzyme production of calcium stearate was attempted by lipase. Lipase having the highed hydrolyzing activity at $60^{\circ}C$, a melting point of substrate (hydrogenated beef tallow),was selected. 60% of hydrogenated beef tallow was converted into calcium stearate in 48hr. This result showed the possible replacement of conventional waste-producing process into enzymetic reaction.

• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.836-839
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• 2000

Beef tallow, which is an industrial lipid substrate, was hydrolyzed by lipase immobilized on a high-density polyethylene (HDPE) powder. Ethanol pre-washing process affected the immobilization efficiency. Half-life of storage of the HDPE at $4^{\circ}C$ was 150 days. And after 10 times of repeated use, more than 50% of initial activity remained. An apparent Michaelis constant ($K_m$) and maximum velocity ($V_{max}$) were 2.7M, and 1.4 mmol/min/l for immobilized lipase, and 0.5 M, and 1.9 mmol/min/l for soluble lipase, respectively.

• BMB Reports
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• 제34권3호
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• pp.274-277
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• 2001

Lipase of Staphylococcus sp. was purified from the culture supernatant, and its molecular mass estimated to be 44 kDa by SDS-PAGE. Its optimum temperature and pH for the hydrolysis of p-nitrophenyl substrates was $28^{\circ}C$ and pH 8.5, respectively The gene encoding the lipase was cloned in Escherichia coli in the $NH_2$-teminally truncated form by using the shotgun method, and sequenced. The mature enzyme had a 49-93% amino acid sequence homology with other staphylococcal lipases. This lipase was used for the hydrolysis of the 3-O-acetate of cephalosporin-C to give an intermediate, deacetylated cephalosporin-C that is useful for further chemical elaborations.

• 산업기술연구
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• 제7권
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• pp.59-68
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• 1987

In order to obtain a strain of producing lipase which has resistance against alkaline and detergent, a screening test was carried out. Among 500 strains isolated from soil samples, the strain J-19 was selected for this study. The composition of the optimum medium for the highest lipase production was 2.0% glycerin, 1.0% corn steep liquor, 2.0% yeast extract, 0.1% $MgSO_4$ $7H_2O$, 0.2% $K_2HPO_4$, 1.5% soybean oil and 0.1% LAS(linear alkylbenzene sulfonate) with initial pH value of 10.0 and 3-day cultivation at $25^{\circ}C$. The lipase activity of the strain J-19 under optimal condition was 3.3. units/ml, which was increased about 1.3-fold than that of basal medium.

• Natural Product Sciences
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• 제18권2호
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• pp.116-120
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• 2012

Pancreatic lipase digests dietary fats by hydrolysis, which is a key enzyme for lipid absorption. Therefore, reduction of fat absorption by the inhibition of pancreatic lipase is suggested to be a therapeutic strategy for obesity. We previously reported coumarins and secoiridoids of Fraxinus rhynchophylla as inhibitory constituents on adipocyte differentiation. Further investigation on F. rhynchophylla led to the isolation of lignan derivatives such as lignans (1 - 10), sesquilignans (11 - 14) and coumarinolignans (15 - 17). Among them, coumarinolignans and sesquilignans were first reported from Fraxinus species. Among the constituents isolated, sesquilignans showed the significant inhibition on pancreatic lipase, whereas lignans and coumarinolignans exerted weak effects.

• Mycobiology
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• 제36권3호
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• pp.167-172
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• 2008

Beef luncheon meat is one of the most popular meals in several countries in the world including Egypt. Thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in Qena. Alternaria, Aspergillus, Emericella, Mucor, Mycosphaerella, Penicillium and Rhizopus were the most common genera on the two types of media. From the above genera, the most prevalent species were Alternaria alternate, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emericella nidulans, Mucor racemosus, Mycosphaerella tassiana, Penicillium chrysogenum and Rhizopus stolonifer. Screening of fungi for their abilities to produce lipase enzyme showed that, ten isolates represented 32.26% of total isolates appeared high lipase production, while sixteen isolates (51.61%) were moderate and 5 isolates (16.13%) were low producers. Aspergillus niger, Fusarium oxysporum and Nectria haematococca produced the highest amount of lipase enzyme, so these fungi were used in further studies. The incorporation of five food preservatives (Disodium phosphate, sodium benzoate, citric acid, potassium sorbate and sodium citrate) individually in the culture medium of lipase production exhibited an inhibitive effect on the mycelial growth and enzyme production by Aspergillus niger, Fusarium oxysporum and Nectria haematococca.

• 한국자원식물학회지
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• 제26권3호
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• pp.374-382
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• 2013

The objective of this study was determined to evaluate ${\alpha}$-amylase, ${\alpha}$-glucosidase, pancreatic lipase inhibition in vitro and DPPH radical scavenging activity of the several Korean resources plants. The ${\alpha}$-amylase inhibitory activity of Salicornia herbacea, Erythronium japonicum (flower) and Phragmites communis (root) in water extract showed relatively high 62.8%, 66.5% and 69.3%, respectively. The ${\alpha}$-amylase inhibitory activity of Citrus junos (pericarp) and Cornus officinalis in methanol extract was found to have an effect with 32.8% in Citrus junos (pericarp) and 60.9% in Cornus officinalis. Corylopsis coreana in both water and methanol extract had the highest ${\alpha}$-glucosidase inhibitory activity of 81.7% and 89.5%, while the extract of Portulaca oleracea, Ficus carica and Citrus junos was not measured ${\alpha}$-glucosidase inhibitory activity at given experiment concentration. Depending on the extraction solvent and the plant species, it was observed that there was a significant difference in ${\alpha}$-glucosidase inhibitory activity. The pancreatic lipase inhibitory activity showed relatively higher in the methanol extract than water extract except pericarp of Citrus junos. The DPPH radical scavenging activity of selected plants was much difference between measured plant species, and showed that the increase was proportional to the concentration. These results suggested that selected plants had the potent biological activity on carbohydrate, lipid Inhibitory activity and antioxidant activity, therefore these plant resources could be a good materials to develop medicinal preparations, nutraceuticals or health functional foods for diabetes or obesity.

• Journal of Microbiology and Biotechnology
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• 제28권5호
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• pp.739-747
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• 2018

The low solubility and high-cost recovery of Propionibacterium acnes polyunsaturated fatty acid isomerase (PAI) are key problems in the bioproduction of high value-added conjugated linoleic acid (CLA). To improve the solubility of recombinant PAI, six chaperone proteins were coexpressed with PAI. Introduction of GroELS proteins dramatically improved the PAI solubility from 29% to 97%, with increased activity by 57.8%. Combined expression of DnaKJ-GrpE and GroELS proteins increased the activity by 11.9%. In contrast, coexpression of DnaKJ-GrpE proteins significantly reduced the activity by 57.4%. Plasmids pTf16 harboring the tig gene and pG-Tf2 containing the tig and groEL-groES genes had no visible impact on PAI expression. The lytic protein E was then introduced into the recombinant Escherichia coli to develop a cell autolysis system. A 35% activity of total intracellular PAI was released from the cytoplasm by suspending the lysed cells in distilled water. The PAI recovery was further improved to 81% by optimizing the release conditions. The lipase from Rhizopus oryzae was also expressed in E. coli, with an extracellular activity of 110.9 U/ml. By using the free PAI and lipase as catalysts, a joint system was established for producing CLA from sunflower oil. Under the optimized conditions, the maximum titer of t-10,c-12-CLA reached 9.4 g/l. This work provides an effective and low-cost strategy to improve the solubility and recovery of the recombinant intracellular PAI for further large-scale production of CLA.

• 한국수산과학회지
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• 제3권4호
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• pp.207-212
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• 1970

멸치절임의 숙성 및 저장 중의 효소 활성 VBN, 세균수, 식염 함유량, 산도, amino-N pH 그리고 지방의 산가에 다음과 같은 결과를 얻었다. 1) Protease 활성은 염수 염장 중에는 증가하고 절임 중에는 식초산의 영향으로 감소하고 이후 차차 거의 일정하게 변화하며 이에 따라 amino-N는 대개 증가하여 숙성한다. 2) Lipase 활성은 염수 염장 중에는 감소하며 vinegar의 첨가로 일단 증가하였다가 절임중에는 증감의 일정한 경향을 볼 수 없다. 그리고산도는 대개 증가하고 있다. 3) VBN와 NaCl 농도는 염수 염장 중에는 급격히 증가하고 절임중에서는 VBN는 완만한 증가를 하며 NaCl 농도는 기의 변화가 없었다. 4) 세균수는 염수 염장함으로써 줄었다가 다시 증가하며 절임함으로써 급격한 감소를 보이고 그 이후에는 일정한 수를 유지 하였다. 5) 절임 제품의 저장성을 유지하기 위해서는 육질의 산도가 $2\%$ 이상이 되도록 vinegar의 산도를 높혀 주어야한다. 6) 염수 염장하는 기간은 8일이 적합하였으며 VBN, 산도, amino-N, lipase 활성 및 관능 검사 성적을 보아서 절임한 후 47일까지 보장할 수 있고 32일 때가 가장 맛이 좋았다.

• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.277-288
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• 2017

Rhizomucor miehei NRRL 5282 and Rhizopus oryzae NRRL 1526 can produce lipases with high synthetic activities in wheat bran-based solid-state culture. In this study, the purification and biochemical characterization of the lipolytic activities of these lipases are presented. SDS-PAGE indicated a molecular mass of about 55 and 35 kDa for the purified R. miehei and Rh. oryzae enzymes, respectively. p-Nitrophenyl palmitate (pNPP) hydrolysis was maximal at $40^{\circ}C$ and pH 7.0 for the R. miehei lipase, and at $30^{\circ}C$ and pH 5.2 for the Rh. oryzae enzyme. The enzymes showed almost equal affinity to pNPP, but the $V_{max}$ of the Rh. oryzae lipase was about 1.13 times higher than that determined for R. miehei using the same substrate. For both enzymes, a dramatic loss of activity was observed in the presence of 5 mM $Hg^{2+}$, $Zn^{2+}$, or $Mn^{2+}$, 10 mM N-bromosuccinimide or sodium dodecyl sulfate, and 5-10% (v/v) of hexanol or butanol. At the same time, they proved to be extraordinarily stable in the presence of n-hexane, cyclohexane, n-heptane, and isooctane. Moreover, isopentanol up to 10% (v/v) and propionic acid in 1 mM concentrations increased the pNPP hydrolyzing activity of R. miehei lipase. Both enzymes had 1,3-regioselectivity, and efficiently hydrolyzed p-nitrophenyl (pNP) esters with C8-C16 acids, exhibiting maximum activity towards pNP-caprylate (R. miehei) and pNP-dodecanoate (Rh. oryzae). The purified lipases are promising candidates for various biotechnological applications.