• Proceedings of the Korean Society of Life Science Conference
• /
• 2007.10a
• /
• pp.76.2-76.2
• /
• 2007

See Full Text

• Proceedings of the Korean Society of Life Science Conference
• /
• 2007.10a
• /
• pp.77.1-77.1
• /
• 2007

See Full Text

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.3
• /
• pp.520-525
• /
• 1999

Changes of chemical and oxidative/antioxidative characteristics chlorophylls(CHLs) and their derivatives in the model system of mustard leaf kimchi(MLK) were investigated. During fermentation of MLK(at 15oC, for 25days, 2.3$\pm$ 0.1% salt content) pH and total acidity were decreased/increased from 5.6 and 0.4%(initial day) to 3.6 and 1.07%(final day) resceptively. Activities of lipoxygenase and peroxidase were decreased gradually, however, these of chlorophyllase was increased in the first 10 days of fermentation. CHLs of MLK in the initial stage of fermentation were degraded rapidly and all CHLs and chlorophyllides were converted to pheophytins and pheophorbides in the final stage. Deg radation effects of CHLs(a & b) and their derivatives(pheophytins a & b) fractionated from MLK and carotene on the autoxidation and lipoxygenase oxidation of linoleic acid were observed, and also stronger antioxidative activities of CHLs and pheophytins were shown in their autoxidation/enzymtic oxidation of linoleic acid.

• Proceedings of the Korean Society of Food and Cookery Science Conference
• /
• 1985.12a
• /
• pp.138.3-138
• /
• 1985

• 한국당과학회:학술대회논문집
• /
• 2006.11a
• /
• pp.56-56
• /
• 2006

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2020.06a
• /
• pp.209-209
• /
• 2020

• Biomolecules & Therapeutics
• /
• v.5 no.1
• /
• pp.87-93
• /
• 1997

DA-5018, a new capsaicin derivative, showed potent analgesic effect comparable to that of morphine in various experimental acute pain models. in this study, whether the analgesic mechanism of DA-5018 is related to opiate receptors or prostanoids was investigated. The affinity of DA-5018 for opiate receptor was determined by receptor binding assay. The Ki values of DA-5018 for nonspecific and specific $\mu$, $textsc{k}$, $\delta$-opiate receptor was 299$\pm$8.88, 735$\pm$215, 2930$\pm$ 163, 1550$\pm$813 nM, respectively and DA-5018 exhibited lower affinity than morphine. DA-5018 (10-"~3$\times$10-′M) inhibited electrically-evoked contractions of the guinea ply ileum and rat vas deferens, and these inhibition was not antagonized by naloxone(10 nM), an opiate receptor antagonist. Antagonism of analgesic effect of 7A-5018 by naloxone was examined by tail pinch test. Analgesic action of DA-5018(0.1 ~2 mg/kg, 5.c.) was not antagonized by naloxone(1 mg/rg, i.p.). These results indicate that pharmacological action of DA-5018 is not related with opiate receptor. Cyclooxygenase and 5-lipoxygenase activities in rat peritoneal neutrophil treated with A23187 and arachidonic acid were measured by radioimmunoassay. DA-5018 stimulated the cyclooxygenase activity and the concentration show-ing the two fold increase of activity was 124$\mu$M. DA-5018 slightly inhibited 5-lipoxygenase activity and these results together indicate that analgesic action of 3A-5018 is not mediated through inhibition of cyclooxy genase or lipoxygenase. These results suggest that the analgesic effect of DA-5018 is not due to blocking opiate receptor or to inhibiting the synthesis of prostanoids in the arachidonic acid metabolism pathway.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.27 no.6
• /
• pp.704-711
• /
• 1994

Lipoxygenase of mackerel gill exhibited the highest reactivity toward eicosapentaenoic acid (EPA) followed by arachidonic acid, linoleic acid. The optimum pH were pH 4.5, 5.0 and 4.8 for EPA, arachidonic acid and linoleic acid, respectively. The enzyme was the most stable at pH 5.5. Optimum temperature was $25^{\circ}C$ for all substrate fatty acids. For linoleic and arachidonic acids the highest thermal stability was observed at $8^{\circ}C$ whereas, for (EPA) at $20^{\circ}C$. Optimum ionic strength was 0.22M, $Sn^{2+}$, vitamin E and catechin completely inhibited the enzyme at the concentration of 1.0mM. Molecular weight of the enzyme was 42,000 dalton.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.10
• /
• pp.1701-1707
• /
• 2016

Lipoxygenase (LOX) is an industrial enzyme with wide applications in food and pharmaceutical industries. The available structure information indicates that eukaryotic LOXs consist of N terminus β-barrel and C terminus catalytic domains. However, the latest crystal structure of Pseudomonas aeruginosa LOX shows it is significantly different from those of eukaryotic LOXs, including the N-terminal helix domain. In this paper, the functions of this N-terminal helix domain in the soluble expression and catalysis of P. aeruginosa LOX were analyzed. Genetic truncation of this helix domain resulted in an insoluble P. aeruginosa LOX mutant. The active C-terminal domain was obtained by dispase digestion of the P. aeruginosa LOX derivative containing the genetically introduced dispase recognition sites. This functional C-terminal domain showed raised substrate affinity but reduced catalytic activity and thermostability. Crystal structure analyses demonstrate that the broken polar contacts connecting the two domains and the exposed hydrophobic substrate binding pocket may contribute to the insoluble expression of the C terminus domain and the changes in the enzyme properties. Our data suggest that the N terminus domain of P. aeruginosa LOX is required for its soluble expression in E. coli, which is different from that of the eukaryotic LOXs. Besides this, this N-terminal domain is not necessary for catalysis but shows positive effects on the enzyme properties. The results presented here provide new and valuable information on the functions of the N terminus helix domain of P. aeruginosa LOX and further improvement of its enzyme properties by molecular modification.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.2
• /
• pp.296-305
• /
• 2020

Tricholoma matsutake is an ectomycorrhizal fungus, related with the host of Pinus densiflora. Most of studies on T. matsutake have focused on mycelial growth, genes and genomics, phylogenetics, symbiosis, and immune activity of this strain. T. matsutake is known for its unique fragrance in Eastern Asia. The most major component of its scent is (R)-(-)-1-octen-3-ol and is biosynthesized from the substrate linoleic acid by the sequential reaction of lipoxygenase and peroxide lyase. Here, we report for the first time the biosynthesis of (R)-(-)-1-octen-3-ol of T. matsutake using the yeast Saccharomyces cerevisiae as a host. In this study, cDNA genes correlated with these reactions were cloned from T. matsutake, and expression studies of theses genes were carried out in the yeast Saccharomyces cerevisiae. The product of these genes expression study was carried out with Western blotting. The biosynthesis of (R)-(-)-1-octen-3-ol of T. matsutake in recombinant Saccharomyces cerevisiae was subsequently identified with GC-MS chromatography analysis. The biosynthesis of (R)-(-)-1-octen-3-ol with S. cerevisiae represents a significant step forward.