• 한국균학회지
• /
• 제14권1호
• /
• pp.79-84
• /
• 1986

Ganoderma lucidum의 개체배양물(個體培養物)로 부터 얻은 cellulase를 ammonium sulfate fractionation으로 조정제(組精製)한 후(後) 이 효소(酵素)의 기본적(基本的)인 특성(特性)을 조사(調査)하였다. 이 효소(酵素)의 최적작용(最摘作用) pH와 온도(溫度)는 각각 pH $4.0{\sim}7.0$사이와 $50^{\circ}C$ 이하(以下)의 온도(溫度)에서는 비교적(比較的) 안정(安定)하였다. CMC-2Na분해(分解)에 대한 activation energy는 6.2 Kcal/mole이었다. $Mg^{++},\;Co^{++}$에 의해서 효소활성(酵素活性)이 증가(增加)되었으나 $Hg^{++}$에 의해서는 저해(沮害)되었다. 한편 본(本) 효소활성(酵素活性)은 SDS에 의해서 약 27%저해(沮害)된 것을 제외(除外)하고는 여러가지 chemical reagents에 의해서는 아무런 영향(影響)을 받지 않았다. 본(本) 효소(酵素)의 CMC-2Na에 대한 Km치(値)는 2.4 mg/ml였으며 CMC-2Na 이외(以外)에 천연(天然) cellulose에도 작용(作用)을 하였다.

• 한국식품영양과학회지
• /
• 제21권6호
• /
• pp.706-711
• /
• 1992

Papain과 pepsin에 의한 부분 가수분해가 번데기 농축단백질의 기능적 특성에 미치는 영향을 검토하였다. TCA 가용성 질소량을 측정하여 얻은 가수분해 정도는 papain으로 10분과 60분간 처리한 결과 각각 10.23%와 19.17% 였으며 pepsin으로 10분과 60분간 처리한 경우는 각각 15.41%와 21.41%로 나타났다. 효소처리한 번데기 농축단백질의 질소 용해도는 실험한 pH 전범위에서 증가하였으며 특히 papain과 pepsin 모두 60분 처리한것이 10분간 처리한것 보다 높게 나타났다. 0.03M $CaCl_2$를 첨가한 결과 전반적으로 질소 용해도가 증가하는 경향을 나타내었다. 번데기 농축단백질의 겉보기 밀도는 papain으로 처리시 차이가 나타나지 않았으며 pepsin의 겨우는 다소 증가하는 경향이었다. 수분 흡수력의 경우 pepsin으로 10분간처리한것 이외에는 큰차이를 나타내지 않았으나 지방흡수력은 papain과 pepsin으로 부분 가수분해한 결과 전반적으로 증가하였다.

• 한국미생물·생명공학회지
• /
• 제19권5호
• /
• pp.477-486
• /
• 1991

Aspergillus niger가 생산하는 $\alpha$-galactosidase의 효소학적 성질을 조사하기 위하여 시험균주를 밀기울 배양한 후 생성된 $\alpha$-galactosidase를 염석, 이온교환 크로마토그래피 및 겔 여과 등의 방법으로 정제한 후 정제효소의 효소학적 성질을 검토하였다. Asp. niger를 밀기울 배지에서 $30^{\circ}C$, 4일 배양했을 때 효소활성이 가장 높았으며 $\alpha$-galactosidase는 황산암모늄 염석, DEAE-cellulose 및 DEAE-Sephadex A-50 이온교환 크로마토그래피, sephadex G-150 겔 여과 등에 의하여 23.7배까지 정제되었으며 비활성이 1,229U/mg.protein, 수율 14이었고 HPLC와 PAGE에 의해 순도가 확인되었다.

• Toxicological Research
• /
• 제12권2호
• /
• pp.155-161
• /
• 1996

The enzymatic properties for NADPH-P450 reductase domain of a fusion protein between human cytochrome P450 1A1 and rat NADPH-P450 reductase expressed in Escherichia coli were investigated. The fusion plasmid pCW/1A1OR-expressed E. coli membrane showed high NADPH-cytochrome c reductase activity ($830.1\pm 85.8 nmol\cdot min^{-1}\cdot mg protein^{-1}$), while pCW control vector and P 450 1A1 expression vector pCW/1A1 showed relatively quite low activity ($4.35\pm 0.49, 3.27\pm 0.50 nmol\cdot min^{-1}\cdot mg protein^{-1}$, respectively). The kinetic curves for NADPH-cytochrome c reductase followed typical Michaelis-Menten kinetics. The $K_{max}$ and $V_{max}$ for NADPH-dependent reductase activity were $8.24\pm 2.61\mu $and $817.9\pm 60.8 nmol\cdot min^{-1}\cdot mg protein^{-1}$, respectively, whereas those for cytochrome c-dependent reductase activity were $19.97\pm 2.86\mu M$ and $1303.5\pm 67.1 nmol\cdot min^{-1}\cdot mg protein^{-1}$. The reductase activities were also compared with those of rat, porcine and human liver microsomes. The activity of pCW/ 1A1OR-expressed E. coli membrane was 15.2-fold higher than that of rat liver microsome. Treatment with benzo(a)pyrene, 7-ethoxyresorufin and $\alpha$-naphthofiavone which are known as specific substrates or inhibitor for human P450 1A1 increased NADPH-cytochrome c reductase activity of fusion protein in E. coli membrane dose-dependently. These results demonstrate that the membrane topology of fused enzyme may be important for activity of its NADPH-P450 reductase domain.

• Journal of Ginseng Research
• /
• 제46권2호
• /
• pp.304-314
• /
• 2022

Background: Ginsenosides are biologically active components of ginseng and have various functions. In this study, we investigated the immunomodulatory activity of a ginseng product generated from ginseng powder (GP) via enzymatic bioconversion. This product, General Bio compound K-10 mg solution (GBCK10S), exhibited increased levels of minor ginsenosides, including ginsenoside-F1, compound K, and compound Y. Methods: The immunomodulatory properties of GBCK10S were confirmed using mice and a human natural killer (NK) cell line. We monitored the expression of molecules involved in immune responses via enzyme-linked immunosorbent assay, flow cytometry, NK cell-targeted cell destruction, quantitative reverse-transcription real-time polymerase chain reaction, and Western blot analyses. Results: Oral administration of GBCK10S significantly increased serum immunoglobulin M levels and primed splenocytes to express pro-inflammatory cytokines such as interleukin-6, tumor necrosis factor-α, and interferon-γ. Oral administration of GBCK10S also activated NK cells in mice. Furthermore, GBCK10S treatment stimulated a human NK cell line in vitro, thereby increasing granzyme B gene expression and activating STAT5. Conclusion: GBCK10S may have potent immunostimulatory properties and can activate immune responses mediated by B cells, Th1-type T cells, and NK cells.

• 한국수산과학회지
• /
• 제55권1호
• /
• pp.1-9
• /
• 2022

This study was conducted to compare the sensory and enzymatic properties of Israeli carp Cyprinus carpio muscle (ICM) according to size [normal large (NLF) and small fish (NSF)], part [ventral (VM) and dorsal muscles (DM)], and commercial value [NLF, recessive (RF), or deformed fish (DF)]. There was not difference in salty of all samples. The sourness was stronger in NLF and DM than in NSF, RF, and DF, and VM, respectively. The umami of ICM showed no size-associated differences; however, those of DM, and DF and RF, were superior to those of the VM and NLF, respectively. The sweetness was also stronger in NLF than in NSF and RF, and in DM than VM. The sweetness of DF didn't differ compared to those of NLF and RF. The intensity of fish odor was weaker in NSF or DF than that in NLF, and was higher in DM than in VM. The color of ICM was bright in NSF and DF compared to NLF. Enzyme activity was very low in the muscles and high in viscera. Therefore, ICM could be used as a material for seafood products, regardless of size, part, and commercial value; however, the issue of lipid oxidation must be considered.

• Food Science and Biotechnology
• /
• 제16권3호
• /
• pp.485-488
• /
• 2007

Plentiful amount of spent yeast has been produced as a by-product from breweries. ${\beta}-Glucan$ was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude ${\beta}-glucan$ preparation consisted of mainly glucan (53% of total wt), containing approximately 35% ${\beta}-glucan$ content of total weight. The effects of crude ${\beta}-glucan$ substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast ${\beta}-glucan$ into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/${\beta}-glucan$ suspension than in flour/${\beta}-glucan$ suspension. It was suggested that preparation of yeast ${\beta}-glucan$ into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

• Journal of Microbiology and Biotechnology
• /
• 제16권8호
• /
• pp.1185-1191
• /
• 2006

The expression of a pullulanase gene in Pichia pastoris was investigated. The gene encoding pullulanase was cloned by PCR using the chromosomal DNA of Bacillus naganoensis as the template. The expression vector pPIC9K-Pu was constructed by inserting the pullulanase gene into plasmid pPIC9K and then transformed into Pichia pastoris SMD 1168 by electroporation. Activity determination, SDS-PAGE, and PCR amplification indicated that the gene of the pullulanase from B. naganoensis had successfully been expressed in SMD 1168 and the molecular size of the expressed recombinant product was about 119.9 kDa. This is the first report on the successful expression of the pullulanase from B. naganoensis in P. pastoris. The transformant secreted recombinant pullulanase with the activity of 350.8 IU/ml in shake-flask culture. The properties of the recombinant pullulanase were characterized.

• 펄프종이기술
• /
• 제42권2호
• /
• pp.75-81
• /
• 2010

Characteristics of mixing biodegradable polymers and polymer impregnated paper for mulching mat for seedling were investigated. The mixed film of 70% PLA was most easily biodegradable. The surface of polymer films were changed to more rough due to enzymatic degradation of lipase. Tensile strength and breaking elongation of PLA mixed films were increased to the 0.04-0.31 kN/m and the 0.17-0.96%, respectively. With higher PLA contents, intensities of ester originated carboxyl group(about $1,748cm^{-1}$) were increased. Physical properties of prepared mulching mats were increased with PLA contents and stiffness of mulching mat was not so much changed.

• 한국환경과학회지
• /
• 제14권3호
• /
• pp.359-366
• /
• 2005

Starch was crosslinked with epichlorohydrin. Crosslinked starch-filled waterborne acrylate (CSWAC) films were prepared by blending this crosslinked starch with waterborne acrylate. The thermal and mechanical properties of these films were investigated by thermogravimetric analysis (TGA), tensile strength and elongation test. The biodegradability was also studied by determination of reduced sugar products after enzymatic hydrolysis and the surface morphology was investigated by scanning electron microscopy (SEM). The CSW AC film showed significantly higher tensile strength and elongation than those of starch-filled waterbonre acrylate (SWAC). The biodegradability of this film was higher than that of native starch-filled acrylate film, and was increased by the addition of crosslinked starch to the acrylate film.