• Applied Biological Chemistry
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• v.36 no.2
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• pp.86-92
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• 1993

Myrosinase from radish was purified by DEAE Bio-Gel, Con-A, and Superose-6 column. The purified myrosinase(II) possessed 2 subunits, and their molecular as determined by SDS-polyacrylamide gel electrophoresis were 53 and 39 KD, respectively. The specific activity of purified enzyme was 37,500 units/mg. The enzyme was purified approximately 44-fold compared to the crude enzyme. Optimum pH of the myrosinase was $6.5{\sim}7.0$ in phosphate and Tris-HCl buffer solutions. Optimum temperature of the enzyme was $37{\sim}38^{\circ}C$. The enzyme was stable at pH 7.0, and less than $30^{\circ}C$. Cu or Hg ion significantly inhibited the enzyme activity, but ascorbic acid enhanced, resulting in a maximum activity by 1 mM ascorbic acid. Among the ascorbic acid analogues, dehydroascorbic acid did not affect, whereas others showed a little effect, but less than ascorbic acid itself. Individual 2-mercaptoethanol and dithiothreitol (reducing agents) did not enhance the enzyme activity. but 2-mercaptoethanol effect was enhanced when mixed with ascorbic acid.

• Applied Biological Chemistry
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• v.37 no.1
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• pp.49-55
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• 1994

An acidic protein, RCG-2, containing chitinase and ${\beta}-1,3-glucanase$ activity conccurrently was purified from rice leaves by chromatofocusing and gel slicing. The purified enzyme gave a single band on polyacrylamide gel electrophoresis and its molecular weight was appeared to be 29.7 kd using SDS-PAGE. This enzyme also had lysozyme activity. The optimal temperature for both enzyme activities was $40^{\circ}C$, optimal pH were 4.0 for chitinase activity and 7.0 for ${\beta}-1,3-glucanase$ activity. $K_M$ and $V_{max}$ values for chitinase were 7.86 mM and $0.025\;{\mu}M/min.$, and those for ${\beta}-1,3-glucanase$ were 5.95 mM and $0.16\;{\mu}M/min.$ respectively. TLC analysis of the enzyme hydrolysates of chitooligosaccharides indicated that this enzyme acts as endochitinase.

• Applied Biological Chemistry
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• v.36 no.2
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• pp.121-126
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• 1993

To extract insoluble proteins of sesame meal residue by using microorganism, the sesame meal residue was treated with crude enzyme solution from Bacillus sp. CW-1121. It was found that the solubility reached to maximum at pH 7.5, $45^{\circ}C$. Under optimum condition, the nitrogen solubility with the enzyme solution from Bacillus sp. CW-1121 reached to 60% in 2 hours. Nitrogen solubility of protein from sesame meal showed minimum value at pH 4.5 and significantly increased above pH 6.0. When the protein from sesame meal extracted with Bacillus sp. CW-1121 was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis, water soluble protein was showed 4 bands and salt soluble protein was showed 2 bands. The amino acid composition of water soluble protein, salt soluble protein and free amino acid indicated relatively high contents of serine (17.24 mg/g), glutamic acid (10.77 mg/g) and glutamic acid (6.55 mg/g). Specially, the contents of essential amino acids were high.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.14-22
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• 1980

White and black sesame produced in Korea were defatted with ethyl ether or n-hexane. Defatted sesame meal was extracted with water and salt solution, and protein extraction was precipitated at various pH 1 through 12, with trichloro acetic acid (TCA), tannic acid and ammonium sulfate, respectively. Protein was purified by Sephadex A-25, G-75, G-100 and G-200, and identified its protein fraction by polyacrylamide gel electrophoresis. Amino acids composition of protein in white sesame was analyzed by automatic amino acid analyzer. Protein contents of white sesame, black sesame and sesame meal are 20.5%, 19.2%, and 44.7%, respectively. n-Hexane was the most suitable solvent for extraction of oil from sesame. Crude protein precipitation was better in higher pH. The protein extraction was more effective with the solution containing sodium chloride tinder the pH 8. Globulin in total protein was high and prolamin was less than in other cereal proteins. Glutamic acid contents of white sesame and sesame globulin were 17.1%, and 20%, respectively. Both proteins contained relatively high levels of essential amino acids. 12-13 bands were found in water soluble protein and 2 bands in salt soluble protein were detected by the disc gel electrophoresis, and were identified in both of white and black sesame. The salt soluble protein of white sesame could be purified by Sephadee G-100 and G-200.

• Applied Biological Chemistry
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• v.30 no.4
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• pp.293-299
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• 1987

Bradyrhizobium japonicum spheroplasts were prepared by culturing cells in the presence of glycine, follwed by treatment with lysozyme. The cells were examined by electron microscopy during the formation of spheroplast. Then Ti plasmid from Agrobacterium tumefaciens 15955 was introduced into Bradyrhizobium japonicum by glycine-lysozyme induced spheroplast transformation. After cell wall regeneration, transformants were selected by the ability of utilization of octopine. Transformation were received at a frequency of $1{\times}10^{-7}$. The transformants obtained from spheroplast transformation harbored the introduced Ti plasmid, which was identified by agarose gel electrophoresis. Furthermore, the differences in their gene products were observed between the transformant and the recipient cell by two-dimensional polyacrylamide gel electrophoresis. The transformants which still possessed the same ability nodulate soybean (Glycine max.) as that of the original host strain, acquired the ability to induce tumor on Petunia hybrida like Agrobacterium, but formed the small crown galls in size compared to those of Agrobacterium tumefaciens.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.3
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• pp.31-38
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• 2014

Four actual cultivations were prepared and a variety of soybean was cultivated. A H-flume, an automatic water level gauge and an automatic water sampler were installed at the outlet of each plot equipped for the measurement of flow rate and its water quality. The amount of rainfall of the study area in 2013 was measured as 975.6 mm which was much lower than the annual average rainfall of 1,271.8 mm, resulting in less occurrences in rainfall-runoff events. Rainfall-runoff events were occurred three times during the rainfall event of 4~5 July, 23 and 24 August. The characteristics of NPS pollution discharge of the plots and the reduction effect of the selected BMPs were analyzed during these events. The reduction effect of straw mat and soil amendments (Polyacrylamide (PAM) and Gypsum) on runoff ratio ranged between 38.2 and 92.9% (average 71.6%). The NPS pollution load reduced between 27.7 and 95.1% (average 70.0%) by the application of rice straw mat and soil conditioner when compared with that of control plot. Soybean yield (2,133.3 kg/ha) of the straw mat covered plots increased by 14.3% when compared with control (1,866.7 kg/ha). The effect of straw mat on the yield was not economically viable if the material and accompanying labor costs were considered. The data collected and analyzed on different soil textures and crops in this study are expected to be a fundamental reference for the expansion of the results to the application nationwide and the development of NPS pollution management policies.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.129-136
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• 2007

This study was performed to determine the protein profiles using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Angiotensin-I-converting enzyme(ACE) inhibitory activity (IC50) as affected by the various meat cuts, digestion times with pepsin. Hydrolysates having the protein concentration of 10 ug/mL had approximately 36∼39% ACE inhibitory activities, regardless of meat cut and digestion time. Protein concentration and ACE inhibitory activity of the diluted hydrolysate increased after 1-hr digestion. In original hydrolysates, ACE inhibitory activities of loin had higher than those of round (P<0.05). In addition, non-heated hydrolysates had higher ACE inhibitory activities than heated counterparts. When myosin B was digested by pepsin more than 1 hr, improved ACE inhibitory activities were observed as compared to the non-digested control.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.134-139
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• 1990

A strain of Nuruk yeast No. IS (NY-15) which produced high activity of ${\beta}-galactosidase$ was isolated from Nuruk, and the crude enzyme was prepared by whey permeate culture of the microorganism. The crude enzyme was purified 40-fold with a 7.7% yield by acetone and ammonium sulfate fractionational precipitation, and chromatography on DEAE-cellulose, DEAE-Sephadex A-50 and Agarose-PAPT. Purified ${\beta}-galactosidase$ from Nuruk yeast showed two types of subunit patterns; a slow moving band and a fast moving deeply stained band, both anode·migrating at pH 7.5. The molecular weight of the former was estimated to be about 130,000 and that of the latter was 96,000 by SDS-polyacrylamide gel electrophoresis. The optimum pH of the enzyme activity was 7.5 and maximum activity appeared at $40^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.317-325
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• 2001

For heuristic purposes, the relative ratio of urease contents inside and outside cells was surveyed using nine ureB+ strains of Helicobacter pylori. the ratio of the enzyme specific activity appeared to vary greatly between the various H. pylori strains, ranging from 0.5 to 2.5. Besides the above compartment, urease was also richly found in the membrane fraction, especially in either peripheral or integral form. The urease distribution across the H. pylori membrane was significantly influenced by the ambient pH; the specific activity of external urease was highest at pH 5.5 with a narrow plateau, whereas the internal specific activity was highest within a pH range of 4.5 to 6.5 with a broad plateau. These finding strongly suggest that H. pylori urease is secretory and responded to the external pH. However, at pH 4.0 or below, no urease activity was detected in either the internal or external compartment, although an increase in the color development with 2,4,6-trinitrobenzene sulfonate (TNBS) was observed. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that these phenomena may be related to a specific proteolysis in certain proteins, including urease or ${\gamma}$-glutamyl transpeptidase. Interestingly, the effect of ammonium ions n alleviating the enzyme inactivation inside the H. pylori cells was remarkably similar to that of D-glucose. In addition, it would appear that the cation acted as a surrogate of not only $Na^+$ but also $K^+$ thereby increasing the H. pylori P-type ATPase activity. This is of great interest, as it implies that the urease action in H. pylori is indispensible at any locus.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.450-455
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• 1998

Aspergillus oryzae M-2-3 strain (argB$\^$-/) was transformed with pTAalp plasmid which was constructed for expression of the alkaline pretense gene, alpA, and 16 transformants were selected on arginine minus medium. When these transformants were tested for productivity of alkaline proteases using agar plate containing skim milk, the halo was observed around each colony of transformants, but not observed around the host strain in this condition. Southern analysis showed that the pTAalp plasmid having alpA gene was integrated into the chromosome of the host strain. The highest level of alkaline protease production was obtained in the culture filtrate of the transformant No. 14, which was estimated to 80-90% of total secreted proteins, and the enzyme activity was 64-450 times higher than those of host strain and industrial strain. Total nitrogen content and the digestion rate in soybean Koji extracts were also increased to 1.5 times in Aspergillus oryzae transformant No. 14.