• Microbiology and Biotechnology Letters
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• v.14 no.4
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• pp.319-324
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• 1986

After intraspecific fusion of Lactobacillus casei protoplasts, the recombinants have been studied for their lactose utilization, protease activity and phage resistance. L. casei C-M phenotypes constituted 46% of the fused cells when tested against phages, and L. casei 3-M phenotypes 42% of the fused cells, and 12% of the recombinants developed the resistance to both parent types of phages. The acid production and proteolytic activity of recombinants evidenced the similar trends. There was no difference in Hind III digests of plasmid DNA between parent cells and recombinants, but the reconlbinant cells were found to possess only one type of plasmid, either of 1. casei C-M or of L. casei 3-M.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1495-1502
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• 2014

Metarhizium anisopliae is a widely studied model to understand the virulence factors that participate in pathogenicity. Proteases such as subtilisin-like enzymes (Pr1) and trypsin-like enzymes (Pr2) are considered important factors for insect cuticle degradation. In four M. anisopliae strains (798, 6342, 6345, and 6347), the presence of pr1 and pr2 genes, as well as the enzymatic activity of these genes, was correlated with their virulence against two different insect pests. The 11 pr1 genes (A, B, C, D, E, F, G, H, I, J, and K) and pr2 gene were found in all strains. The activity of individual Pr1 and Pr2 proteases exhibited variation in time (24, 48, 72, and 96 h) and in the presence or absence of chitin as the inductor. The highest Pr1 enzymatic activity was shown by strain 798 at 48 h with chitin. The highest Pr2 enzymatic activity was exhibited by the 6342 and 6347 strains, both grown with chitin at 24 and 48 h, respectively. Highest mortality on S. exigua was caused by strain 6342 at 48 h, and strains 6342, 6345, and 6347 caused the highest mortality 7 days later. Mortality on Prosapia reached 30% without variation. The presence of subtilisin and trypsin genes and the activity of these proteases in M. anisopliae strains cannot be associated with the virulence against the two insect pests. Probably, subtilisin and trypsin enzyme production is not a vital factor for pathogenicity, but its contribution is important to the pathogenicity process.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.176-185
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• 2016

Yeonsan Ogae has been known as supporting health and high efficacy of treatment. In recent days, as the efficacy of functional peptides has known, the optimization of oligo peptides production and its characteristics from Ogae legs has been performed. Response surface method was used to perform the optimizaion of enzyme hydrolysis. The range of processes was temperature ( 40, 50 and $60^{\circ}C$), pH( pH 6.0, 7.0 and 8.0 ), and enzyme( 1, 2 and 3% ). The degree of hydrolysis, amino acids, molecular weight of products were analyzed. The optimum process of enzyme hydrolysis were determined as temperature $58^{\circ}C$, pH 7.5, and enzyme concentration 3%. At optimum conditions, the degree of hydrolysis after 2 h reaction was 75-80%. The amino acid and were 168.131 mg/100 g, respectively. The molecular weight of products by using MALDI-TOF was ranged from 300 to 1,000 Da.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.72-77
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• 2001

The effect of gamma-irradiation on the microbiological and general quality changes of the kochujang(Korean hot pepper paste) was studied. Kochujang was prepared, irradiated at 5, 10 and 20 kGy, and then stored at $25^{\circ}C$ for twelve weeks. The results showed that the Bacillus were decreased by 5 log cycles with dose of 20 kGy with 3.94 kGy of $D_{10}$ value. Yeast and Lactobacillus cells were nearly eliminated by 10 kGy. The formation of $NH_2-nitrogen$ and reducing sugar, enzyme activity, acid production and browning were not affected by gamma irradiation. Therefore, it was considered that the kochujang treated with gamma irradiation maintained better microbial quality than that of the control with storage.

• Journal of Life Science
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• v.21 no.12
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• pp.1716-1720
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• 2011

A bacterium hydrolysing various organic materials including cellulose, protein, starch and lipid was isolated. The isolate was identified as Bacillus subtilis, and named Bacillus subtilis CK-2 in this paper. This bacterium showed optimal growth at $40\sim45^{\circ}C$, pH 6~9, and 0~3% of NaCl. B. subtilis CK-2 seemed to synthesis highly active autolysin. The hydrolytic enzymes produced by B. subtilis CK-2 were primary enzymes because extracellular enzyme activities varied similarly to the growth curve. The hydrolytic enzymes seemed to be stable at basic pH conditions. From these results, B. subtilis CK-2 was found to bea useful bacterial agent for composting, or for use in feed-production waste in agriculture, fishery, forest materials, livestock farming, and food.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1125-1130
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• 1997

The effects of enzyme combination, pH, acid washing and enzyme treatment sequence were investigated in the hydrolysis of soy protein. Comparing Alcalase vs. Neutrase/Alcalase, it appeared that Neutrase/Alcalase was more efficient than Alcalase alone, as the highest degree of hydrolysis (DH) was seen in Neutrase/Alcalase. A surprisingly high DH (more than 60%) was observed with Flavourzyme in the second hydrolysis. The separation of insolubles from the first hydrolysis had little effect on the second hydrolysis. When the washing water from the first hydrolysis was reused in the next hydrolysis, the DH and protein recovery were increased. The addition of calcium ion showed not so much positive effects by the stabilization of Neutrase on the Protein hydrolysis. The use of carbohydrase and repeated acid washing gave positive effects on DH. The simultaneous treatment using endoprotease and exoprotease with pH adjustment improved DH significantly.

• Parasites, Hosts and Diseases
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• v.49 no.3
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• pp.245-254
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• 2011

Many immune down-regulatory molecules have been isolated from parasites, including cystatin (cystain protease inhibitor). In a previous study, we isolated and characterized Type I cystatin (CsStefin-1) of the liver fluke, Clonorchis sinensis. To investigate whether the CsStefin-1 might be a new host immune modulator, we induced intestinal inflammation in mice by dextran sodium sulfate (DSS) and treated them with recombinant CsStefin-1 (rCsStefin-1). The disease activity index (DAI) increased in DSS only-treated mice. In contrast, the DAI value was significantly reduced in rCsStefin-1-treated mice than DSS only-treated mice. In addition, the colon length of DSS only-treated mice was shorter than that of rCsStefin-1 treated mice. The secretion levels of IFN-${\gamma}$ and TNF-${\alpha}$ in the spleen and mesenteric lymph nodes (MLNs) were significantly increased by DSS treatment, but the level of TNF-${\alpha}$ in MLNs was significantly decreased by rCsStefin-1 treatment. IL-10 production in both spleen and MLNs was significantly increased, and IL-$10^+F4/80^+$ macrophage cells were significantly increased in the spleen and MLNs of rCsStefin-1 treated mice after DSS treatment. In conclusion, rCsStefin-1 could reduce the intestinal inflammation occurring after DSS treatment, these effects might be related with recruitment of IL-10 secreting macrophages.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.934-940
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• 1998

Kochujang, fermented hot pepper soybean paste, was prepared by traditional method, and irradiated with gamma ray of $^{60}Co{\;}up{\;}to{\;}15{\pm}1.5{\;}kGy$ for confirming main factor of kochujang fermentation. Nonirradiated (control) and irradiated samples kochujang were fermented at $25^{\circ}C$ and analyzed biochemical properties including enzyme activities and viable cell count during fermentation for 60 days. The total viable count in irradiated kochujang decreased to $10^4{\;}CFU/g$ which was $10^8{\;}CFU/g$ in the control. Because of a little changing enzyme activities of ${\alpha}{\cdot}{\beta}{\;}amylase$ and acid neutral protease by irradiation at the above level, amino type nitrogen which is the main quality reference of kochujang was comparable to the control. By irradiation, gas production was completely stopped which is one of biggest problems during distribution of kochujang. Total volume of gas produced at $25^{\circ}C$ from the control kochujang was 453 mL/100 g which was composed of over 90% of $CO_2$. The odor of irradiated kochujang was inferior to the control which seemed to be related to reduced microbial populations.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.505-510
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• 2002

An improved kinetic assay for prekallikrein activator (PKA), a potential vasodilator, has been developed to be used as an indicator for quality control during production of human albumin preparations. It consists of two reaction stages. In the first stage, PKA and prekallikrein are incubated at $37^{\circ}C$ for 45 min to allow the transformation into kallikrein. Kallikrein, a serine protease, catalyzes the splitting of p-nitroaniline (pNA) from its substrate H-D-Pro-Phe-Arg-pNA(S-2302). The rate at which pNA is released was measured spectrophotometrically at 405 nm. Prekallikrein, a substrate of PKA was purified by DEAE ion-exchange chromatography and the major potential variations in the assay were optimized; pH 8.0 and 150 mM sodium chloride were chosen to give a proper ionic strength. Reaction times in the range of 10 to 360 min provided linear dose-response curves. The concentration of prekallikrein was adjusted to fall between 1:1 and 1:3 dilutions to generate a linear standard calibration curve. Under the optimized conditions, reproducibility was checked. In a precision test, the coefficient of variation (CV) stayed within ${\pm}4%$ and the dose-response curve showed a good correlation (${r^2}=0.999$). An accuracy test with an international standard of PKA afforded a mean recovery of 97.5%.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1844-1853
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• 2019

Objective: We investigated how pituitary adenylate cyclase-activating polypeptide (PACAP) affects embryonic development during pre-in vitro maturation (pre-IVM) using porcine oocytes isolated from small follicles. Methods: We divided the follicles into the experimental groups by size (SF, small follicles; MF, medium follicles) and treated with and without PACAP and cultured for 18 hours (PreSF[-]PACAP; without PACAP, Pre-SF[+]PACAP; with PACAP) before undergoing IVM. The gene expression related to extracellular matrix formation (amphiregulin, epiregulin, and hyaluronan synthase 2 [HAS2]) and apoptosis (Bcl-2-associated X [BAX], B-cell lymphoma 2, and cysteine-aspartic acid protease 3) was investigated after maturation. The impact on developmental competence was assessed by the cleavage and blastocyst rate and total cell number of blastocysts in embryos generated from parthenogenesis (PA) and in vitro fertilization (IVF). Results: Cleavage rates in the Pre-SF(+)PACAP after PA were significantly higher than SF and Pre-SF(-)PACAP (p<0.05). The cleavage rates between MF and Pre- SF(+)PACAP groups yielded no notable differences after IVF. Pre-SF(+)PACAP displayed the higher rate of blastocyst formation and greater total cell number than SF and Pre-SF(-)PACAP (p<0.05). Cumulus cells showed significant upregulation of HAS2 mRNA in the Pre-SF(+)PACAP compared to the SF (p<0.05). In comparison to other groups, the Pre-SF(+)PACAP group displayed a downregulation in mRNA expression of BAX in matured oocytes (p<0.05). Conclusion: The PACAP treatment during pre-IVM improved the developmental potential of porcine oocytes derived from SF by regulating cumulus expansion and apoptosis of oocytes.