• Journal of Marine Life Science
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• v.6 no.1
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• pp.1-8
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• 2021

In marine ecosystems, the biosynthesis and catabolism of dimethylsulfoniopropionate (DMSP) by marine bacteria is critical to microbial survival and the ocean food chain. Furthermore, these processes also influence sulfur recycling and climate change. Recent studies using emerging genome sequencing data and extensive bioinformatics analysis have enabled us to identify new DMSP-related genes. Currently, seven bacterial DMSP lyases (DddD, DddP, DddY, DddK, DddL, DddQ and DddW), two acrylate degrading enzymes (DddA and DddC), and four demethylases (DmdA, DmdB, DmdC, and DmdD) have been identified and characterized in diverse marine bacteria. In this review, we focus on the biochemical properties of DMSP cleavage enzymes with special attention to DddD, DddA, and DddC pathways. These three enzymes function in the production of acetyl coenzyme A (CoA) and CO₂ from DMSP. DddD is a DMSP lyase that converts DMSP to 3-hydroxypropionate with the release of dimethylsulfide. 3-Hydroxypropionate is then converted to malonate semialdehyde by DddA, an alcohol dehydrogenase. Then, DddC transforms malonate semialdehyde to acetyl-CoA and CO₂ gas. DddC is a putative methylmalonate semialdehyde dehydrogenase that requires nicotinamide adenine dinucleotide and CoA cofactors. Here we review recent insights into the structural characteristics of these enzymes and the molecular events of DMSP degradation.

• Mycobiology
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• v.51 no.1
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• pp.49-59
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• 2023

Antrodia cinnamomea, an edible and medicinal fungus with significant economic value and application prospects, is rich in terpenoids, benzenoids, lignans, polysaccharides, and benzoquinone, succinic and maleic derivatives. In this study, the transcriptome of A. cinnamomea cultured on the wood substrates of Cinnamomum glanduliferum (YZM), C. camphora (XZM), and C. kanehirae (NZM) was sequenced using the high-throughput sequencing technology Illumina HiSeq 2000, and the data were assembled by de novo strategy to obtain 78,729 Unigenes with an N50 of 4,463 bp. Compared with public databases, about 11,435, 6,947, and 5,994 Unigenes were annotated to the Non-Redundant (NR), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genome (KEGG), respectively. The comprehensive analysis of the mycelium terpene biosynthesis-related genes in A. cinnamomea revealed that the expression of acetyl-CoA acetyltransferase (AACT), acyl-CoA dehydrogenase (MCAD), 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA), mevalonate pyrophosphate decarboxylase (MVD), and isopentenyl diphosphate isomerase (IDI) was significantly higher on NZM compared to the other two wood substrates. Similarly, the expression of geranylgeranyltransferase (GGT) was significantly higher on YZM compared to NZM and XZM, and the expression of farnesyl transferase (FTase) was significantly higher on XZM. Furthermore, the expressions of 2,3-oxidized squalene cyclase (OCS), squalene synthase (SQS), and squalene epoxidase (SE) were significantly higher on NZM. Overall, this study provides a potential approach to explore the molecular regulation mechanism of terpenoid biosynthesis in A. cinnamomea.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.2
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• pp.102-108
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• 2016

Mitochondrial encephalopathy, lactic acidosis, and stroke-like episode (MELAS) syndrome is one of mitochondrial encephalopathy. As the early clinical manifestations can be variable, it is important to suspect the disease, especially in patients with multiple organ dysfunctions. A boy was diagnosed with epilepsy when he was 9 years old. Two years later, severe headache and blurred vision developed suddenly. On examination, left homonymous hemianopsia was detected with corresponding cerebral parenchymal lesions in right temporo-occipito-parietal areas. MELAS syndrome was confirmed by genetic test, which showed m.3243 A>G mitochondrial DNA mutation. Multivitamins including coenzyme Q10 were added to anticonvulsant. He experienced 4 more events of stroke-like episodes over 5 years, but he is able to perform normal daily activities. A 13-year-old boy was brought to the hospital due to suddenly developed respiratory arrest and asystole associated with pneumonia. Past medical history revealed that he had multiple medical problems such as epilepsy, failure-to-thrive, optic atrophy, and deafness. He has been on valproic acid as an anticonvulsant which was prescribed from local clinic. He recovered after the resuscitation, but his cognition and motor function were severely damaged. He became bed-ridden. He was diagnosed with MELAS syndrome by brain MRI, muscle biopsy, and clinical features. Genetic test did not reveal any mitochondrial gene mutation. Four years later, he expired due to suddenly developed severe metabolic acidosis combined with hyperglycemic hyperosmolar nonketotic coma. The clinical features of MELAS syndrome are variable. Early diagnosis before the presentation to the grave clinical course may be important for the better clinical outcome.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1847-1855
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• 2015

Supercritical carbon dioxide ($SC-CO_2$) treatment has been becoming an important method for substituting the use of organic solvents for samples extraction prior to analysis due to its low toxicity, ease of handling, low cost of disposal etc. Freeze-dried bovine liver was treated with $SC-CO_2$ under different pressures (200, 300, and 450 bar) in order to investigate effects on physicochemical properties and reduction of microbial load. The yield of lipid extraction from bovine liver by $SC-CO_2$ treatment increased with increasing pressure, with values of 84, 86, and 90% in response to 200, 300, and 450 bar, respectively. Results of high performance liquid chromatography analysis showed that vitamin A and coenzyme $Q_{10}$ ($CoQ_{10}$), which is soluble in lipid, were almost removed from bovine liver by $SC-CO_2$ treatment. Saturated fatty acids ratio of bovine liver decreased with increasing pressure, whereas polyunsaturated fatty acids increased with increasing pressure. Total content of amino acids in bovine liver treated by $SC-CO_2$ was less than that of the control sample without treatment. The number of aerobic bacteria in bovine liver, which was stored at $5^{\circ}C$ for 5 days and freeze-dried, decreased from 6.2 to 4.2 log CFU/g by $SC-CO_2$ treatment at 100 bar for 3 h. Interestingly, coliform bacteria were not found in the bovine liver sample by $SC-CO_2$ at 100 bar for 3 h under all storage conditions. This indicates that $SC-CO_2$ treatment can effectively reduce coliform bacteria in the food matrix even at low moisture. In conclusion, freeze-dried bovine liver by proper $SC-CO_2$ treatment may be used as a potential high protein source, with increasing microbial safety and stability of lipid oxidation.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.31-40
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• 2013

This study was performed to investigate the investigated effects of dietary supplementation of vitamin C and E on the growth performance and stress response in broiler chickens. Stress response was analyzed by the quantity of telomeric DNA, the rate of DNA damage and the expression levels of heat shock proteins (HSPs) and hydroxyl-3-methyl-glutaryl coenzyme A reductase (HMGCR) genes on tissues and blood. The telomere length and telomere shortening rates were analyzed by quantitative fluorescence in situ hybridization on the nuclei of lymphocytes and tissues. The DNA damage rate of lymphocytes was quantified by the comet assay. The expression levels of HSP70, HSP90s and HMGCR genes were measured by quantitative real-time polymerase chain reaction in lymphocytes. In results, there was no significant difference among treatments in body weight, weight gain, feed intake and mortality. The telomere shortening rate of the lymphocytes was significantly lower in the vitamin E supplemented group than the control group. The DNA damage was also decreased supplemented with vitamin C and E, as compared to the control group. The vitamin E supplemented group had a significant positive effect on the expressions of HMGCR, HSP90-${\alpha}$ and HSP90-${\beta}$ in lymphocytes, but had no significance on HSP70, as compared to the control group. We concluded that the dietary supplementation of vitamin E (100 mg/kg feed) had reduced the individual physiological stress response without stunt growth in broiler chickens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1235-1241
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• 2012

Antioxidant properties and antioxidant compound contents in different parts of 14 commercial mushrooms were evaluated. Methanolic extracts from the entire mushroom, the pileus and the stipe, separately, were screened for their DPPH and ABTS free radical scavenging activities. Total ubiquinones (Coenzyme Qs; CoQs), total phenolic, and flavonoid contents were determined, in order to assess the extract's antioxidant activity. The portion of the mushroom selected had an effect on the results, with pileus methanolic extract exhibiting the greatest antioxidant effect (p<0.05). The analyzed mushrooms contained powerful antioxidants such as phenols (144.5~536.6 mg of gallic acid equivalents, mg GAE/100 g of dried weight, dw), flavonoids (3.7~31.2 mg of quercetin equivalents, mg QE/100 g dw) and ubiquinones (65.6~485.1 ${\mu}g$/100 g dw). Content of CoQ9 and CoQ10 in the 14 commercial mushrooms varied from 23.1 to 256.2 ${\mu}g$/100 g and from 16.1 to 238.3 ${\mu}g$/100 g, respectively. Phellinus linteus showed the highest antioxidant activity among all species due to the contribution of antioxidants such as phenols (530.5 mg GAE/100 g dw) and ubiquinones (308.8 ug/100 g dw). A positive linear correlation was demonstrated between free radical scavenging activity and total phenolic ($R^2=0.79$) and ubiquinone ($R^2=0.59$) contents in the pileus of mushrooms (p<0.05). Our data indicate that commercial mushrooms have potential as dietary sources of CoQs and phenolic antioxidants.