• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.544-549
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• 1995

The alkaline elastase is an extracellular serine protease of the alkalophilic Bacillus strain Ya-B. To increase the gene copy number and the production level of the alkaline elastase Ya-B, we designed, on the B. subtilis chromosome, a gene amplification of the 10.6 kb repeating unit containing amyE, aleE (alkaline elastase Ya-B gene) and tmrB. The aleE was inserted between amyE and tmrB, and B. subtilis APT119 strain was transformed with this amyE-aleE-tmrB-junction region fragment. As a result, we succeeded in obtaining tunicamycin-resistant (Tm$^{r}$) transformants (Tf-1, Tf-2) in which the designed gene amplification of 10.6 kb occurred in chromosome. The transformants showed high productivity of $\alpha $-amylase and alkaline elastase Ya-B. The copy number of the repeating unit (amyE-aleE-tmrB) was estimated to be 25, but plasmid vector (pUC19) was not integrated. The amplified aleE of chromosome was more stable than that of plasmid in absence of antibiotics.

• Microbiology and Biotechnology Letters
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• v.7 no.4
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• pp.217-223
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• 1979

Six strains of mold which had high saccharifying and acid-productive ability were isolated from wild sources. The strain M-80 among them and Aspergillus kawachii, which was generally used as rice makkulli koji were used for this studies. The results obtained were summarized as follows. 1) $\alpha$-amylase activities of the strain M-80 and Asp, kawachii showed similarly as about 140W. V., while $\beta$-amylase activity of M-80 was 54 A. U. and Asp. kawachii was 40 A. U. 2) Acid protease activity of M-80 was higher then Asp. kawachii but alkaline protease activity was lower Asp. kawachii respectively. 3) The contents of total acid, ethanol and fusel oil in makkulli brewing with M-80 were higher those of Asp. kawachii and methanol contents of the tested two strains were about 33mg/％. 4) Fifteen kinds of free amino acid were detected from makkulli brewing of two strains, and free amino acid contents of M-80 were 10％ higher than those of Asp. kawachii.

• Journal of Ginseng Research
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• v.6 no.2
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• pp.131-137
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• 1982

The effect of red ginseng residue on the several enzyme activities of the koji and alcohol fermentation were investigated. The koji showed maximum values of amylase and cellulase activity when it was prepared by 30% red ginseng residue and 70% wheat bran, and of protease activity when it was prepared by 40% red ginseng residue and 60% wheat bran-${\alpha}$ amylase activity of the koji during its fermentation was increased rapidly until 4 days and there after it was increased slowly, but ${\beta}$-amylase was rapidly increased after 3 days fermentation. During the preparation of the koji, the acidic, neutral protease and cellulase activities showed the maximum value after 3 days fermentation and the alkaline protease showed the maximum value within 4-6 days fermentation. On the otherhand, fermented broth, containing 6%(v/v) alcohol, could be obtained when the substrate was saccharified by the koji, based on 25% red ginseng residue and 75% wheat bran, prior to alcohol fermentation.

• Journal of environmental and Sanitary engineering
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• v.24 no.1
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• pp.40-46
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• 2009

The enzyme expressed from strain L-49 was 2.01 times higher than that of original strain. Strain L-49 can grow on culture plate with $50{\mu}g/mL$ ampicillin. The synthesis of $\alpha$-amylase was greatly suppressed when strain L-49 was grown on monosaccharide such as glucose and polysaccharide at the same time cell concentration was low. Amylase production was enhanced when the bacterium was grown on starch and dextrin. Among different nitrogen sources tried, yeast extract was found to be the best followed by panpeptone, peptone, meat extract, bean meal, and corn steep liquor. The average rate of enzyme production was enhanced for 3~4 times in fermentation time from 24h to 44h. The sugar uptake rate has also increased. Low oxygen supply rate enhanced the rate of strain propagation but depressed the enzyme production. Hence it is benefit to obtain high enzyme activity that agitation speed maintained not lower than 400r/min and aeration rate maintained greater than 1:1vvm.

• Microbiology and Biotechnology Letters
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• v.19 no.3
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• pp.290-295
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• 1991

Direct conversion of raw starch without liquefaction to maltose using maltose-forming fungal a-amylase (Fungamyl) was carried out in an agitated bead enzyme reactor (bioattritor). The reaction rate in bioattritor was comparable with conventional method which utilized liquefied soluble starch. Moreover the extent of maltose formation increased substantially compared with conventional method; from 150 g / I of raw starch, around 95 g/l of maltose was formed and 72% of maltose content in sugar mixture was achieved. Especially, pH influenced greatly not only on total sugar formation from raw starch in bioattritor but also on maltose content in sugar mixture. The optimal pH for maltose formation from raw starch was shifted into the weak alkaline pH, the optimal pH of 8.0~9.0 in bioattritor contrast to pH of 5.0~5.5 for liquefied starch. The maltose formation and content were also affected by the amounts of Fungamyl added and raw starch concentration. Consumption of maltose-forming Fungamyl can be substantially reduced by supplementary addition of starch liquefying a-amylase (Termamyl).

• Journal of Ginseng Research
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• v.14 no.1
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• pp.21-26
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• 1990

The chemical composition and stabilities of the purified ginseng invertase were investigated. The purified enzyme was found to be a glycoprotein composed of 80.2% protein and 19.7% total sugar. The protein component of the enzyme was composed of acidic amino acid (9.3%), basic amino acid (48.9%), nonpolar amino acid (21.4%), polar amino acid (20.4%) and 6.1% S-containing amino acid. It showed especially high contents of histidine and serine. The enzyme was inactivated almost completely by the treatment with some proteases (papain, pepsin. trypsin, pancreatin and microbial alkaline pretense) and protein denatllrants (8M urea and 6M guanidine-HC1), bolt not with glyrosidase (${\alpha}$-amylase, ${\beta}$-amylase. glcoamylese and cellullase). btonosaccharides sllch as glilrose, fructose, galactose and mannose did not exert any influence on the enzyme activity. The activity of the enzyme was inhibited by Ag+, Mn2+, Hg2+, Zn2+ and Al3+, whereas Ca2+, Mg2+, Ba2+ and Fe3+ gave rather activating effects on the enzyme activity. The enzyme was relatively stable in the VH range of VH 6 and 8, and at the temperatures below 35$^{\circ}C$.

• Advances in Traditional Medicine
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• v.6 no.3
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• pp.186-195
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• 2006

The present study was carried out to determine the involvement of opioid and non-opioid receptor and the effect of pH and enzymes on the recently reported antinociceptive activity of aqueous extract of Corchorus olitorius (AECO) leaves using the abdominal constriction test. The extract was prepared by soaking the dried powdered leaves of Corchorus (C.) olitorius in distilled water overnight, and the supernatant obtained was considered as a stock solution with 100% concentration/ strength. The extract, administered subcutaneously in the concentrations/ strength of 10, 50 and 100%, was found to show a significant concentration-independent antinociception. The 50% concentration AECO were further used to study on the above mentioned parameters. The extract exhibited: significant (P < 0.05) decreased in activity when pre-treated (s.c.) against 10 mg/kg naloxonazine, bicuculine (10 mg/kg), phenoxybenzamine (10 mg/kg), 10 mg/kg pindolol, and 5 mg/kg mecamylamme, but not 10 mg/kg naltrindole, 10 mg/kg atropine, respectively; significant (P < 0.05) decreased in activity after pre-treatment against 10% a-amylase, but not 1 % protease or 10% lipase and; significant (P < 0.05) decreased in activity after exposure to alkaline condition (pH between 9 and 13) while maintaining the activity at acidic condition, respectively. The C. olitorius leaves antinociception, which involved, at least in part, activation of $\mu-opioid,\;\alpha-and\;\beta-adrenergic$, and nicotinic receptors, was found to decrease under alkaline condition and in the presence of $\alpha-amylase$.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.56-62
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• 1995

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang meju during fermentation for 60 days. The pH of meju decreased continously up to 40 days of aging and then increased slightly thereafter, while the change in titratable acidity showed the opposite trend to that of pH. The viable cell count of aerobic bacteria increared gradually for up to 40 days of fermentation and then decreased slightly thereafter, while that of molds and yeasts showed a rapid increase up to 40 days of fermentation and then leveled off. ${\alpha}-amylase$ activity increased slightly for up to 40 days of meju fermentation and then stabilized. On the other hand, ${\beta}-amylase$ and glucoamylase activities did not show a significant change for up to 20 days of fermentation and then increased rapidly at 40th day of fermentation. Acidic, neutral and alkaline protease activities increased sharply up to 40 days of aging and then decreased significently at 60th day of fermentation. These results suggest that meju fermented for 40 days had the highest quality in terms of the number of microflora and enzyme activity.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.341-346
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• 2016

The AMY2B gene, encoding human pancreatic ${\alpha}$-amylase isozyme (HPA II), was expressed in Pichia pastoris, and the effects of chloride ions on HPA II activity toward starch substrates were investigated. As seen with chloride ion-dependent ${\alpha}$-amylases-including HPA I, the isozyme of HPA II-chloride ions increased enzyme activity and shifted the optimal pH to an alkaline pH. The activity enhancement by chloride was more significant at pH 8 than that at pH 6, suggesting that the protonation state of the general acid/base catalyst of HPA II was important for the hydrolysis of starches at an alkaline pH because of the increase in its $pK_a$ by chloride ions. The turnover values for cereal starches as the substrates markedly increased in the presence of chloride by up to 7.2-fold, whereas that for soluble starch increased by only 1.7-fold. Chloride inhibited substrate hydrolysis at high substrate concentrations, with $K_i$ values ranging from 6 to 15 mg/mL.

• Journal of Life Science
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• v.11 no.1
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• pp.14-21
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• 2001

To investigate the changes of carbohydrate metabolism in the senescing leaves of Zea mays during dark-induced senescence, the changes in the contents of reducing sugar, sucrose and starch as well as the activities of sucrose synthase, three isozymes of invertase, and ${\alpha}$-amylase were measured. In the senescing leaves, the content of reducing sugars temporarily increased at 4 d and rapidly decreased thereafter, whereas sucrose contents gradually decreased thereafter, whereas sucrose contents gradually decreased until 3 d of senscence and significantly decreased thereafter. The activities of intracellular invertases such as soluble acid and alkaline formed gradually enhanced until 4 d of leaf senescence and significantly declined thereafter. The extracellular invertase activity showed no significant changes during leaf senescence. The deactivation of sucrose synthase was observed within 3 d of leaf senscence. On the other hand, the starch contents gradually declined during 2 d of leaf senescence, and showed a temporary increase at 3 d, which is similar to the pattern of sucrose synthase activity., These results imply that sucrose in the senescing leaves. The major enzymes which correlated to the breakdown of sucrose during dark-induced senescence were soluble acid and alkaline invertases, not sucrose and ABA accelerated leaf senescence by inducing the accumulation of reducing sugar. These result, therefore, that leaf senescence may be mediated by the temporary quantitative changes of reducing sugar induced by the activation of intracellualr inveertases.