• Journal of Life Science
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• v.27 no.12
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• pp.1403-1409
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• 2017

In this study, the xylitol dehydrogenase (XYL2) gene was expressed in Saccharomyces cerevisiae as a host cell for ease of use in the degradation of lignocellulosic biomass (xylose). To select suitable expression systems for the S.XYL2 gene from S. cerevisiae and the P.XYL2 gene from Pichia stipitis, $pGMF{\alpha}-S.XYL2$, $pGMF{\alpha}-P.XYL2$, $pAMF{\alpha}-S.XYL2$ and $pAMF{\alpha}-P.XYL2$ plasmids with the GAL10 promoter and ADH1 promoter, respectively, were constructed. The mating factor ${\alpha}$ ($MF{\alpha}$) signal sequence was also connected to each promoter to allow secretion. Each plasmid was transformed into S. cerevisiae $SEY2102{\Delta}trp1$ strain and the xylitol dehydrogenase activity was investigated. The GAL10 promoter proved more suitable than the ADH1 promoter for expression of the XYL2 gene, and the xylitol dehydrogenase activity from P. stipitis was twice that from S. cerevisiae. The xylitol dehydrogenase showed $NAD^+$-dependent activity and about 77% of the recombinant xylitol dehydrogenase was secreted into the periplasmic space of the $SEY2102{\Delta}trp1/pGMF{\alpha}-P.XYL2$ strain. The xylitol dehydrogenase activity was increased by up to 41% when a glucose/xylose mixture was supplied as a carbon source, rather than glucose alone. The expression system and culture conditions optimized in this study resulted in large amounts of xylitol dehydrogenase using S. cerevisiae as the host strain, indicating the potential of this expression system for use in bioethanol production and industrial applications.

• Journal of Ginseng Research
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• v.8 no.1
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• pp.15-21
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• 1984

It has been known that ethyl acetate fraction and petroleum ether fraction prepared from ginseng are inhibitory to the L5178Y and sarcoma 180 cell at the concentrations o! 0.Imgfml or 0.2mg/ml. The shiny was carried out to examine effects of the two fractions on the activities of RNA polymerase, succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) present in normal rabbit liver. The ethyl acetate fraction did not show any inhibitory effect on the RNA polymerase and SDH activity at the concentrations of 0.Imgfml and 0.2mglml, but inhibited malate dehydrogenase activity by 12.3% and 15.5%, at the same concentrations, respectively. The fraction also inhibited all the three enzymes at higher concentrations tested, but stimulated the succinate dehydrogenase activity at 0.024mg/ml to increase the enzyme activity by 14.6%. The petroleum ether fraction activated the SDH activity by 12.9% and 20.8%, at the concentration of 0.1mg/ml and 0.2mg/ml respectively. But the fraction did not affect the MDH activity at the same concentration. The fraction, however, inhibited the MDH activity and activated the SDH activity by 13.5% and 18.2%, at the concentration of 0.8mg/ml respectively.

• Journal of Nutrition and Health
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• v.32 no.4
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• pp.376-383
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• 1999

The effects of $\beta$-carotene substitutionl for vitamin A and the chronic consumption of ethanol of ethanol on hepatic folate metabolism were studied it rats. The substitution of $\beta$-carotene for vitamin A depressed hepatic 10-formyl-tetreahydrofolate dehydrogenase(10-formyl-tetrahydrofolate : NADP oxidoreductase, E.C. 1.5. 1.6)activity to 65% of controls(p<0.001) and enhanced hepatic 5, 10-methy-lenetetrahydrofolate reductase(E. C. 6.3.3.2)activity by 56% with respect to control levels(p<0.001). Hepatic activity of 10-formyltertrahydrofolate dehydrogenase was depressed to about half that of control levels by ethanol administration to rats(36% ethanol diet, p<0.001). The activity of 5, 10-methyleneterahydrofolate reductase was not changed by ethanol consumption. The increased activity of 5, 10-methyleneterahydrofolate reductase and the decreased activity of 10-formyltetrahydrofolate dehydrogenase appeared to decrease the level of nonmethyl folate conezyme and the rate of one-carbon metabolism. Plasma homocysteine concentrations were significantly higher in rats fed ethanol(p<0.01) o $\beta$-carotene(p<0.001) than in controls, which suggests that increased activity of 5, 10-methylenetetrahydrofolate reductase can depress homocysteine metabolism. We concluded that dietary substitution of $\beta$-carotene for vitamin A or chronic administration of ethanol resulted in changes in the activity of hepatic folate-dependent enzymes, which could affect the distribution of folate derivatives, plasma homocysteine levels and one-carbon metabolism.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.49-51
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• 1984

After pretreatment with ginseng followed by induction of acute intoxication of alcohol, the activities of alcohol dehydrogenase (ADH), microsomal ethanol-oxidizing system (MEOS) and aldehyde dehydrogenase(Ald DH) increased respectively compared to the groups treated with alcohol alone. In case that ginseng was given to rats fed with 5% alcohol instead of water for 60 days, the activities of ADH and MEOS increased compared to the groups treated. On the contrary, the activity of Ald DH in mitochondrial fraction decreased to an extent of about 35% in chronic alcoholism, but after pretreatment of ginseng the activity was restored to the control level. On the other hand, the catalase activity was not significantly affected by either treatment. Ginseng butanol fraction significantly increased the serum isocitrate dehydrogenase activity which is inhibited by alcohol-treated in rat. Alcohol-induced lactate dehydrogenase activity was decreased to control level in liver by ginseng treatment. And the serum level of lactic acid also decreased by ginseng treatment in alcohol-intoxicated rat. Ginseng butanol fraction markedly decreased the xanthine oxidase activity in the ethanol-treated rat liver. It was also observed that ginseng reduced the blood concentration of uric acid on experimentally reduced hyperuricemia by alcohol treatment. Uricase activity was not affected by either treatment. Ginseng butanol fraction decreased the hepatic aniline hydroxylase activity which was induced by alcohol-treated rat. These results suggest that the treatment with ginseng can be promoted the recovery from alcohol intoxication and some therapeutic effect on alcoholinduced metabolic disease.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.171-175
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• 1995

Effects of $Biozyme_{R}$ and $\textrm{Business}_{R}$ on alcohol metabolism in rats, and on the activities of alcohol dehydrogenase(ADH) and acetaldehyde dehydrogenase(ALDH) were studied in vitro. Alcohol concentration in rat blood was decreased after the treatment of Business(3.3 mι/kg, Biozyme 1.67 mg/wι) and Biozyme(3.3 mι/kg, 1.67 mg/mι) prior to the administration of ethanol(25%, 0.83 g/kg). And the acetaldehyde concentration of rat blood was also decreased when compared with control values in the same condition. Effects of Biozyme on ADH and ALDH activity were also studied. While the ALDH activity was elevated in the presence of Biozyme(2 $\mu\textrm{g}$/assay), the ADH activity was not influenced by Biozyme at the concentration range from 2 $\mu\textrm{g}$/assay to 0.2 mg/assay. In summary, Biozyme accelerated the rate of ethanol metabolism and the acceleration might be due to the increase in ALDH activity.vity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.15-18
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• 1998

The entanol productivity of superoxide dismutase (SOD)-deficient mutants of Saccharo-Myces cerevisiae was examined under the oxidative stress by Paraquat. It was observed that MnSOD-deficient mutant of S. cerevisiae had higher ethanol productivity than wild type or CuZnSOD-deficient yeast both in aerobic and in anaerobic culture condition. Pyruvated dehydrogenase activity decreased by 35% and alcohol dehydrogenase activity increased by 32% were observed in MnSOD-deficient yeast grown aerobically. When generating oxygen radicals by Paraquat, the ehanol productivity was increased by 40% in CuZnSOD-deficient or wild strain, resulting from increased activity of alcohol dehydrogenase and decreased a activity of pyruvate dehydrogenase. However, the addition of ascorbic acid with Paraquat returned the enzyme activities at the level of control. These results imply that SOD-deficiency in yeast strains may cause the metabolic flux to shift into anaerobic ethanol fermentation in order to avoid their oxidative damages by Paraquat.

• Biomaterials and Biomechanics in Bioengineering
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• v.3 no.1
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• pp.37-46
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• 2016

To maintain activity in a coenzyme/enzyme mixture system, such as ${\beta}$-nicotinamide adenine dinucleotide (NADH)/dehydrogenase, the water-soluble 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers as an additive were synthesized and investigated for their stabilizing function. The inhibitor for the NADH/dehydrogenase reaction was spontaneously formed when the NADH was stored in the dehydrogenase solution. Therefore, we hypothesized that if the additive polymer could interact with an inhibitor without any adverse effect on the dehydrogenase, the activity in the NADH/dehydrogenase mixture could be maintained. We selected lactose dehydrogenase (LDH) as the enzyme, and the NADH was dissolved and incubated at $37^{\circ}C$ in the LDH solution containing the polymers. The phospholipid polymers used in this study were poly(MPC) (PMPC), poly(MPC-co-3-trimethylammonium-2-hydroxypropyl methacrylate chloride) (PMQ) and poly[MPC-co-potassium 3-methacryloyloxypropyl sulfonate ($MSO_3$)] ($PMMSO_3$). The poly($MSO_3$) was used as a reference. For the PMQ and $PMSO_3$ aqueous solutions, the activity of the NADH/LDH mixture system decreased with incubation time as the same level or lower than that in the Tris buffered solution in the absence of the polymers. However, for the poly($MPC-co-MSO_3$) ($PMMSO_3$) aqueous solution, the activity of the NADH/LDH mixed system was six times higher than that in the buffered solution even after a 3-days incubation. The LDH activity was 1.5-1.8 times higher in the presence of the $PMMSO_3$ compared with that in the $PMSO_3$ solution. The mixture of two polymers, poly(MPC) and poly($MSO_3$), did not produce any stabilization. Thus, both the MPC and $MSO_3$ units in the polymer chain had important and cooperative effects for stabilizing the NADH/LDH mixture.

• Journal of Nutrition and Health
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• v.24 no.4
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• pp.350-355
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• 1991

The effect of thyroid hormone on hepatic levels of 10-formyltetrahydrofolate dehydrogenase (10-formyltetrahydrofolate : NADP oxidoreductase, E.C. 1.5.1.6.) was studied using Sprague-Dawley rat. Hypothyroidism increased histidine oxidation by 5 fold and increased 10-formyltetrahydrofolate dehydrogenase activity by 142%, and also decreased methylenetetrahydrofolate reductase activity by 52%. Decreased methylenetetrahydrofolate reductase acts by decreasing synthesis of 5-methyl folate, thereby increasing the proportion of non-methyl folate required for folate-dependent reactions. Increased histidine oxidation produced by hypothyroidism may be attributed to its effect in decreasing 10-formyltetrahydrofolate dehydrogenase.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.669-673
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• 2002

An extracellular limonoate dehydrogenase was purified 10-fold from a cell-free extract of Rhodococcus fascians by ammonium sulfate precipitation, dialysis, and ultrafiltration. This purified dehydrogenase catalyzed the conversion of limonoate to 17-dehydrolimonoate. The enzyme showed optimum activity at pH 8.0 and $40^{\circ}C$, with $K_m$ value of 0.9$\muM$, and requires Zn ions and sulfhydryl groups for catalytic action. The enzyme activity was inhibited by $Hg^{2+}\;and\;NaN_3$ ions. The degradation of limonin (66%) in Kinnow mandarin juice was successfully demonstrated with partially purified limonoate dehydrogenase. With scale-up preparation of limonoate dehydrogenase, a successful debittering operation of fruit juices appears feasible.

• Food Engineering Progress
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• v.21 no.3
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• pp.286-291
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• 2017

This study was conducted to certify the effect of aqueous extracts from fifty medicinal plants on the activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in vitro. Each aqueous extract was prepared by combining one-part medicinal plants with twenty-parts distilled water at $80^{\circ}C$ for 8 h. Among the fifty medicinal plants, Allium sativum L. and Cinnamomum cassia Presl were regarded as an effective anti-hangover substance. Allium sativum L. extract increased ALDH activity more than 2 times compared with ADH activity, enhancing the acetaldehyde degradation. Cinnamomum cassia Presl extract dramatically inhibited ADH activity compared with ALDH activity, thus potently decreasing the acetaldehyde formation. ADH and ALDH activities were proportionally inhibited according to the increased concentration of Cinnamomum cassia Presl extract. The aqueous extract of Cinnamomum cassia Presl at a concentration of $45.33{\mu}g/mL$ inhibited ADH activity by 52.8% and ALDH activity by 11.0%.