• 약학회지
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• 제40권5호
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• pp.563-573
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• 1996

The system most likely responsible for the accelerated metabolism of alcohol with chronic ingestion or at high blood ethanol levels, is the microsomal ethanol-oxidizing system(M EOS). While the increase in the MEOS with chronic ethanol ingestion is thought to be adaptive, it may also have serious adverse effects on the liver. The rates of the NADPH-dependent oxygen consumption by the liver microsomes from the prolonged ethanol fed rats were 2 times higher than the rates from the non-treated rats. With the alcohol ingestion, the total SH and nonprotein SH contents showed the significant decrease and at the same time, MDA in liver and GOT and GPT levels in blood showed the significant increase, which suggests the occurrence of liver damage due to the oxidative stress caused by chronic alcohol consumption. The mitochondrial aldehyde dehydrogenase(ALDH) activity was decreased by chronic ethanol ingestion, whereas the alcohol dehydrogenase activity and the cytosolic ALDH activity were not altered. These results suggest that the induction of cytochrome P450 by the chronic alcohol ingestion increases the oxidative stress which seems to result in the altered the physiological states of the liver including the ALDH activity, which may in turn to lead to the liver disease.

• Toxicological Research
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• 제14권2호
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• pp.157-161
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• 1998

The mechanism of active aldehyde-induced liver disease and the enzymatic basis of detoxification were investigated using normal rat liver cell, Ac2F. Aliphatic alcohols including l-decyl alcohol, l-nonanol, l-heptanol, l-hexanol, l-propanol and allyl alcohol exerted a dose- and time-de-pendent toxicity to Ac2F cells. The extent of their toxicities in buthionine sulfoximine (inhibitor of glutathione synthesis) pretreated cells was greater than in pargyline (inhibitor of aldehyde dehydrogenase, ALDH). On the other hand, the toxicity of these alcohols were not affected by 4-methylpyrazole (inhibitor of alcohol dehydrogenase, ADH). These results suggest that the contents of glutathione (GSH) seems to be very important in protecting the cells from toxicants such as aliphatic alcohols.

• Toxicological Research
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• 제14권4호
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• pp.557-562
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• 1998

Allyl alcohol is metabolized in the liver through two steps, first to reactive acrolein by alcohol dehydrogenase (ADH), subsequently to acrylic acid by aldehyde dehydrogenase (ALDH). Since ethanol could compete the same enzymes to be metabolized in the liver, we have determined the plasma concentrations of allyl alcohol and ethanol followed by combined treatment. Pretreatment of rats with 2g/kg ethanol followed by ip administration of 40mg/kg allyl alcohol increased the lethality significantly. Determination of in vivo blood concentrations revealed that ethanol pretreatment caused the apparent decrease in allyl alcohol clearance, whereas acetaldehyde level in blood increased significantly by allyl alcohol treatment, as determined by head space GC analysis. Treatment of 4-methylpyrazole, an inhibitor of ADH, delayed allyl alcohol elimination significantly and reduced its lethality. Collectively, these findings suggested that reduction of allyl alcohol clearance in the presence oj ethanol was mediated through ADH competitive inhibition.

• Journal of Microbiology and Biotechnology
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• 제32권2호
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• pp.170-175
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• 2022

3-Hydroxypropionic acid (3HP) is a platform chemical and can be converted into other valuable C3-based chemicals. Because a large amount of glycerol is produced as a by-product in the biodiesel industry, glycerol is an attractive carbon source in the biological production of 3HP. Although eight 3HP-producing aldehyde dehydrogenases (ALDHs) have been reported so far, the low conversion rate from 3-hydroxypropionaldehyde (3HPA) to 3HP using these enzymes is still a bottleneck for the production of 3HP. In this study, we elucidated the substrate binding modes of the eight 3HP-producing ALDHs through bioinformatic and structural analysis of these enzymes and selected protein engineering targets for developing enzymes with enhanced enzymatic activity against 3HPA. Among ten AbKGSADH variants we tested, three variants with replacement at the Arg281 site of AbKGSADH showed enhanced enzymatic activities. In particular, the AbKGSADH^R281Y variant exhibited improved catalytic efficiency by 2.5-fold compared with the wild type.

• 산업식품공학
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• 제21권3호
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• pp.286-291
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• 2017

약용식물의 열수 추출물이 in vitro에서 alcohol dehydrogenase (ADH)와 aldehyde dehydrogenase (ALDH)의 활성에 미치는 영향을 확인하였다. 약용식물에 20배의 증류수를 넣고 $80^{\circ}C$에서 8시간 추출하여 얻어진 추출액을 시료로 사용하였다. 50종의 약용식물 중에서 마늘과 육계 추출물이 숙취해소 천연소재로서의 활용 가능성이 가장 높게 나타났다. 마늘 추출물은 ADH에 비해 ALDH의 활성을 2배 이상 촉진시킴으로써 acetaldehyde의 분해가 잘 되게 하였다. 육계 추출물은 ALDH의 활성에 비해 ADH의 활성을 획기적으로 저해함으로써 acetaldehyde의 생성을 크게 억제하였다. 육계 추출물은 농도에 비례하여 ADH와 ALDH의 활성을 저해하였으며, $45.33{\mu}g/mL$의 농도에서 ADH의 활성을 52.8% 저해하였고 ALDH의 활성을 11.0% 저해하였다.

• Journal of Ginseng Research
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• 제21권1호
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• pp.53-60
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• 1997

The changes in aldehyde dehydrogenase(ALDH, E.C. 1.2.1.3.) activity in neurons and astrocytes isolated from rat brains were investigated after administration of ethanol and Korean red ginseng(Panax ginseng C.A. Meyer) saponln. The cerebral ALDH activity with acetaldehyde and Propionaldehyde was higher in the white matter than in the gray matter. However, using indole-3-a-cetaldehyde and 3,4-dihydroxyphenylacetaldehyde as substrates, there was no significant difference in activity between two regions in cerebrum. In ethanol treated group, ALDH activity with all the substrates in the gray and white matter was lower than in normal group. In ethanol-saponin treated group, the enzyme activity in the white matter remarkably Increased. The ALDH activity in neurons isolated from cerebral cortex in ethanol-treated group was lower than in normal group. In ethanol-saponin treated group, neuronal ALDH activity with propionaldehyde was significantly recovered but not with Indole-3-acetaldehyde. In astrocytes, although the ALDH activity with propionaldehyde in the ethanol-treated group was not changed as compared with normal group, considerable increase in activity was found in ethanol-saponin treated group. These results suggest that Korean red ginseng saponin may protect the neuronal functions from the toxic effects of acetaldehyde derived from ethanol by stimulation of ALDH activity in astrocytes surrounding nerve cells.

• Journal of Ginseng Research
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• 제18권1호
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• pp.1-9
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• 1994

Sprague-Dawley rats were given freely with 15% ethanol (control) and 15% ethanol containing (1) 0.1% ginseng saponin, (2) 0.02% ginsenoside $Rb_1$, and (3) $Rg_1$ (tests) instead of water for 7 days and aldehyde dehydrogenase (ALDH) and monoamine oxidase (MAO) activity in different regions of brain were examined. In control group, total ALDH activity with indoleacetaldehyde and acetaldehyde as substrate in all different regions was lower than that of normal group except in the hippocampus. The inhibitory effect on the activity was prominent in the corpus striatum and was not in the hippocampus. However, low-$K_m$ ALDH activity in all different regions was much lower than that of normal group. A considerable decrease in mitochondria ALDH activity in cerebellum and striatum was also observed in control group. In test groups total, low-$K_m$, and mitochondria AkDH activities in all different regions were higher than those in control group. Although ALDH activity in the striatum of test group was higher than control group, it was relatively depressed as compared with normal. There was not found a remarkable difference in extent of stimulating effect on the AkDH activity according to the ginseng saponin components. When biogenic aldehydes were used as substrate, ALDH activity with 3,4-dihydroxy-phenylacetaldehyde (DOPAL) in all brain regions of control group was lower than that using 5-hydroxy-indoleacetaldehyde (HIAL) and 3,4-dihydroxyphenylglycolaldehyde (NORAL) as substrate. In control group, ALDH activity with biogenic aldehydes above mentioned was markedly inhibited in the striatum contrary to other regions. The higher ALDH activity with biogenic aldehydes in test group than in control was found in the striatum, cerebrum, and cerebellum. MAO activity in the cerebellum was inhibited in control group and slightly increased in test group. The results of present study suggest that the corpus striatum is significantly affected by ethanol exposure while the hippocampus is not and that ginseng saponin fraction and ginsenosid es might have a preventive effect against depression of brain ALDH activity by chronic administration of ethanol.

• 약학회지
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• 제37권6호
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• pp.647-658
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• 1993

The susceptibilities of aldehyde dehydrogenase (AldDH) and alcohol dehydrogenase (ADH) to active oxygen generated by xanthine-xanthine oxidase (XOD) system were studied. Incubation of AldDH with 2$\times$10$^{-3}$ units of XOD for 30 min at $25^{\circ}C$ resulted in the decrease of enzyme activity to 30% and it was inactivated completely when incubated with 5$\times$10$^{-3}$ units of XOD. Whereas 70% of ADH activity was retained after exposure to 5$\times$10$^{-3}$ units of XOD for 30 min, 40% of ADH activity was retained after exposure to 5$\times$10$^{-2}$ unit of XOD for 30 min. This inhibition effect by the active oxygen was preventable by catalase and glutathione, but not by SOD. The rates of the NADPH-dependent oxygen consumption by the liver S-9 mixture and microsomes were also determined in this study. Rate of oxygen consumption is increased in the liver S-9 mix and microsomes from phenobarbital-treated rat, and it was consistent with increased lipid peroxidation. In the presense of ethanol as a substrate, the oxygen consumption rates were increased. It is reported that hepatic AldDH activity is depressed in alcoholic liver diseases, however there is few report that explains the reason of depressed AldDH activity. These results are supportive of the theory that the increase in hepatic ethanol oxidation through the induced ME activity after chronic ethanol feeding generate oxygen radical at elevated rates and it leads to the depression of AldDH activity.

• Fisheries and Aquatic Sciences
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• 제14권2호
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• pp.79-88
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• 2011

The sea tangle, Laminaria japonica has long been used in Korea as a folk remedy to promote health. Gamma-amino butyric acid-enriched (5.56% of dry weight) sea tangle was obtained by fermentation with Lactobacillus brevis BJ-20 (FLJ). A suppressive effect of FLJ on carbon tetrachloride-induced hepatotoxicity has been shown previously. Alcohol administration to Sprague-Dawley rats leads to hepatotoxicity, as demonstrated by heightened levels of hepatic marker enzymes as well as increases in both the number and volume of lipid droplets as fatty liver progresses. However, FLJ attenuated alcohol-induced hepatotoxicity and the accumulation of lipid droplets following ethanol administration. Additionally, FLJ increased the activities and transcript levels of major alcoholmetabolizing enzymes, such as alcohol dehydrogenase and aldehyde dehydrogenase, and reduced blood concentrations of alcohol and acetaldehyde. These data suggest that FLJ protects against alcohol-induced hepatotoxicity and that FLJ could be used as an ingredient in functional foods to ameliorate the effects of excessive alcohol consumption.

• 대한두경부종양학회지
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• 제17권2호
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• pp.131-138
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• 2001

Objectives: Alcohol intake has been reported to be a risk factor of laryngeal cancer. Since the aldehyde dehydrogenase 2 (ALDH2) genotype is a major determinant of personal alcohol drinking habit, there is a possibility that ALDH2 genotype would be a risk factor for laryngeal cancer. N-Acetyltransferase 2 (NAT2) is a detoxifying enzyme and its polymorphism has been reported to be related to the risk of many environmental cancers. However, studies on the associations between these two genotypes and laryngeal cancer risk are scarce. We have assessed the effects of alcohol intake and the genotype of ALDH2 and NAT2 on the risk of laryngeal cancer in Koreans. Materials and Methods: Eighty-four pathologically proven laryngeal cancer patients and 168 age matched controls were included as the study subjects. Information about alcohol intake and smoking habit was collected using a self administered questionnaire. ALDH2 and NAT2 genotypes were analyzed using PCR-RFLP methods. Results: Alcohol intake was significant as a risk factor for laryngeal cancer (OR : 2.58, 95% CI : 1.24, 5.36), especially for supraglottic laryngeal cancer (OR : 3.24, 95% CI : 1.02, 10.31). Personal drinking habit was closely related with personal smoking habit, which was a potent risk factor of laryngeal cancer. In a stratified analysis according to the level of cumulative smoking amount, drinking was significant neither in light smokers (equal or less than 30 pack-years) nor in heavy smoker (over 30 pack-years). The ALDH2 genotype was significantly associated with the risk of laryngeal cancer in a univariate analysis. The statistical significance, however, disappeared after adjusting alcohol intake using a multiple conditional logistic model. The NAT2 genotype was not significant as a risk factor for laryngeal cancer. Conclusion: Alcohol drinking and ALDH2 genotype would have indirect effects on laryngeal cancer by their correlations with cigarette smoking or with alcohol drinking. It is less likely that the NAT2 genotype would be a potent risk factor of laryngeal cancer.