• BMB Reports
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• v.36 no.2
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• pp.159-166
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• 2003

Cytoplasmic $\alpha$-glycerol-3-phosphate dehydrogenase from fruit-bat-breast muscle was purified by ion-exchange and affinity chromatography. The specific activity of the purified enzyme was approximately 120 units/mg of protein. The apparent molecular weight of the native enzyme, as determined by gel filtration on Sephadex G-100 was $59,500{\pm}650$ daltons; its subunit size was estimated to be $35,700{\pm}140$ by SDS-polyacrylamide gel electrophoresis. The true Michaelis-Menten constants for all substrates at pH 7.5 were $3.9{\pm}0.7\;mM$, $0.65{\pm}0.05\;mM$, $0.26{\pm}0.06\;mM$, and $0.005{\pm}0.0004\;mM$ for L-glycerol-3-phosphate, $NAD^+$, DHAP, and NADH, respectively. The true Michaelis-Menten constants at pH 10.0 were $2.30{\pm}0.21\;mM$ and $0.20{\pm}0.01\;mM$ for L-glycerol-3-phosphate and $NAD^+$, respectively. The turnover number, $k_{cat}$, of the forward reaction was $1.9{\pm}0.2{\times}10^4\;s^{-1}$. The treatment of the enzyme with 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) under denaturing conditions indicated that there were a total of eight cysteine residues, while only two of these residues were reactive towards DTNB in the native enzyme. The overall results of the in vitro experiments suggest that $\alpha$-glycerol-3-phosphate dehydrogenase of the fruit bat preferentially catalyses the reduction of dihydroxyacetone phosphate to glycerol-3-phosphate.

• New & Renewable Energy
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• v.4 no.4
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• pp.56-64
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• 2008

Anaerobic biodegradability (AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical methane potential (BMP) test has been carried out to evaluate the methane yields of animal manures such as pig and cattle slurries, and different forage crops cultivated at the reclaimed tideland such as maize, sorghum, barley, rye, Italian ryegrass (IRG), rape, rush, and waste sludge produced from slaughterhouse wastewater treatment plant (SSWTP). In the ultimate methane yield and biodegradability of animal manure, those of pig slurry were 345 $mlCH_4/gVS_{fed}$ and 44.7% higher than 247 $mlCH_4/gVS_{fed}$ and 46.4% of cattle slurry (Cat. 2). The ultimate methane yield and biodegradability of spike-crop rye (Rye 1) were 442.36 $mlCH_4/gVS_{fed}$ and 86.5% the highest among different forage crops, those of the other forage crops ranged from 306.6 to 379 $mlCH_4/gVS_{fed}$ of methane yield with the AB having the range of about 60 to 77%. Therefore the forage crops could be used as a good substrate to increase the methane production and to improve the biodegradability in anaerobic co-digestion together with animal manure.

• BMB Reports
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• v.37 no.5
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• pp.618-624
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• 2004

All members of R. glutinosa show the unique characteristic of intrinsic tolerance to paraquat (PQ). Antioxidant enzymes have been proposed to be the primary mechanism of PQ resistance in several plant species. Therefore, the antioxidant enzyme systems of R. glutinosa were evaluated by comparatively analyzing cellular antioxidant enzyme levels, and their responses of oxidative stresses and hormones. The levels of ascorbate peroxidase (APX), glutathione reductase (GR), non-specific peroxidase (POX), and superoxide dismutase (SOD) were 7.3-, 4.9-, 2.7- and 1.6-fold higher in PQ-tolerant R. glutinosa than in PQ-susceptible soybeans. However, the activity of catalase (CAT) was about 12-fold higher in the soybeans. The activities of antioxidant enzymes reduced after PQ treatment in the two species, with the exception of POX and SOD in R. glutinosa, which increased by about 40%. Interestingly, the activities of APX, SOD and POX in R. glutinosa, relative to those in soybeans, were further increased by 49, 67 and 93% after PQ treatment. The considerably higher intrinsic levels, and increases in the relative activities of antioxidant enzymes in R. glutinosa under oxidative stress support the possible role of these enzymes in the PQ tolerance of R. glutinosa. However, the relatively lower levels of SOD versus PQ tolerance, and the mixed responses of antioxidant enzymes to stresses and hormones, suggest a possible alternative mechanism(s) for PQ tolerance in R. glutinosa.

• The Korean Journal of Physiology
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• v.4 no.1
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• pp.47-54
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• 1970

The effects of excess salt ingestion or/and a prolonged electrical stimulation of the hypothalamus on the arterial blood pressure were studied in cats. The average mean arterial pressure determined in 12 control animals were $112.2{\pm}2.6\;mmHg$. In 15 animals in which 2% NaCl solution (2g/Kg of body wegight/day) was given for 20 days, average mean arterial pressure elevated to $147.7{\pm}6.1\;mmHg$. It was also found in four of them that salt-induced high blood pressure started to decline when salt solution was replaced by tap water. On the other hand, No change in average mean arterial pressure was observed in 10 animals, whose hypothalamus had been electrically stimulated for 28 days. In 11 animals in which the hypothalamus was stimulated with simultaneous excess salt ingestion for 20 days, there was a marked elevation in average mean arterial pressure which, however, does not significantly differ from that observed in excess salt ingested group. From the results obtained from the present experiment, it is concluded that 1) the hypertension is induced by an excess salt ingestion in cats, 2) the mean arterial pressure of cats is not affected at least by an increment of sympathetic tone for 4 weeks resulting from the electrical stimulation of posterior area of the hypothalamus, 3) in sodium·induced high blood pressure cats, four weeks of increment in sympathetic tone by the hypothalamic stimulation does not further elevate mean arterial pressure.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.2
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• pp.113-120
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• 2000

To investigate the mechanism of smooth muscle contraction induced by emptying of intracellular $Ca^{2+}$ stores, we measured isometric contraction and $^{45}Ca^{2+}$ influx. $CaCl_2$ increased $Ca^{2+}$ store emptying- induced contraction in dose-dependent manner, but phospholipase C activity was not affected by the $Ca^{2+}$ store emptying-induced contraction. The contraction was inhibited by voltage-dependent $Ca^{2+}$ channel antagonists dose dependently, but not by TMB-8 (intracellular $Ca^{2+}$ release blocker). Both PKC inhibitors (H-7 and staurosporine) and tyrosine kinase inhibitors (genistein and methyl 2,5-dihydroxycinnamic acid) significantly inhibited the contraction, but calmodulin antagonists (W-7 and trifluoperazine) had no inhibitory effect on the contraction. The combined inhibitory effects of protein kinase inhibitors, H-7 and genistein, together with verapamil were greater than that of each one alone. In $Ca^{2+}$ store-emptied condition, $^{45}Ca^{2+}$ influx was significantly inhibited by verapamil, H-7 or genistein but not by trifluoperazine. However combined inhibitory effects of protein kinase inhibitors, H-7 and genistein, together with verapamil were not observed. Therefore, this kinase pathway may modulate the sensitivity of contractile protein. These results suggest that contraction induced by emptying of intracellular $Ca^{2+}$ stores was mediated by influx of extracellular $Ca^{2+}$ through voltage-dependent $Ca^{2+}$ channel, also protein kinase C and/or tyrosine kinase pathway modulates the $Ca^{2+}$ sensitivity of contractile protein.

• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.357-361
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• 2013

Several epidemiological surveys have reported the prevalence of Toxoplasma gondii infection in stray cats in Korea, but little information is available on T. gondii infection in household cats. The aim of the present study was to assess the prevalence and risk factors of T. gondii infection among household cats reared in Seoul, Korea. A total of 474 blood samples were collected from clinically healthy household cats. All samples were tested using ELISA and PCR. The risk factor analysis was based on a questionnaire filled out by the owners. The overall positive rate for ELISA and PCR assays was 2.2% (10/437) and 2.1% (10/474), respectively. With regard to the origin of cats, the positive rates among cats adopted from the animal shelter and veterinary clinic for stray cats were significantly different (P<0.05). Our study demonstrated that the positive rate of T. gondii infection in household cats was low and that this low prevalence was assumed to be associated with keeping the cats indoors and restriction of eating raw food and uncooked meat. Therefore, we suggest that the owners check the origin of the cats prior to adoption to prevent infection of other animals, including humans.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.2
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• pp.278-286
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• 2015

The overall purpose of this study was to investigate the effects of Chunggukjang and Greentea-Chunggukjang on the lipid profile, lipid peroxidation and antioxidative enzyme activities of liver tissue in growing male rats fed cholesterol. Twenty seven rats were divided into three treatment groups (Control, Chunggukjang and Greentea-Chunggukjang) and were given experimental diets with 1% cholesterol for 9 weeks. All rats in this study were fed a casein-based diet. Chunggukjang groups were fed diet containing 33.1% Chunggukjang powder. The Chunggukjang and Greentea-Chunggukjang groups showed significantly lower weight gain, food efficiency ratio than the control group regardless of Chunggukjang type. Serum total cholesterol was significantly lower in the Chunggukjang group than in the control group, whereas serum triglyceride and atherogenic index were significantly lower in the Greentea-Chunggukjang group than in the control group. Hepatic triglyceride contents was not significantly different among the diets. However, hepatic cholesterol content was significantly lower in the Greentea-Chunggukjang group than in the control group. Lipid peroxidation of malondialdehyde (MDA) contents was significantly lower in the Chunggukjang and Greentea-Chunggukjang groups than in the control group. Activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) in liver tissue of the Chunggukjang and Greentea-Chunggukjang groups were not significantly different. It can be concluded that Chunggukjang and Greentea-Chunggukjang influence lipid profile and hepatic malondialdehyde contents in growing male rats fed cholesterol.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.15-24
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• 2000

Although nociceptive informations are thought to be processed via different neural mechanisms depending on the types of stimuli, sufficient data have not been accumulated yet. We performed a series of experiments to elucidate the possible neural mechanisms as to chemical stimuli such as formalin, capsaicin and ATP. Single unit activity of wide dynamic range (WDR) neurons and high threshold cells were recorded extracellularly from the lumbosacral enlargement of cat spinal cord before and after chemical stimulation to its receptive field (RF). Each chemical substance - formalin $(20{\mu}l,\;4%),$ capsaicin (33 mM) or Mg-ATP (5 mM)- was injected intradermally into the RFs and then the changes in the spontaneous activity, mechanical threshold and responses to the peripheral mechanical stimuli were observed. In many cases, intradermal injection of formalin (5/11) and capsaicin (8/11) resulted in increase of the spontaneous activity with a biphasic pattern, whereas ATP (8/8) only showed initial responses. Time courses of the biphasic pattern, especially the late response, differed between formalin and capsaicin experiments. One hour after injection of each chemical (formalin, capsaicin, or ATP), the responses of the dorsal horn neurons to mechanical stimuli increased at large and the RFs were expended, suggesting development of hypersensitization (formalin 6/10, capsaicin 8/11, and ATP 15/19, respectively). These results are suggested that formalin stimulates peripheral nociceptor, local inflammation and involvement of central sensitization, capsaicin induces central sensitization as well as affects the peripheral C-polymodal nociceptors and neurogenic inflammation, and ATP directly stimulates peripheral nociceptors.

• Journal of Fisheries and Marine Sciences Education
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• v.11 no.1
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• pp.24-42
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• 1999

I have studied historical transition process of fisheries industries, fisheries Institute in abreast of developing fisheries industries of west coast of Korea since 1910 year with regard to the Gogunsan Is. The results were summarized as follows. In 1910 year, fishery industry has been carried out shifting fishing gear e.g set-net in shallow waters, small stow net, small seine net adapting to the tophorgrapical feature, shape of coast, oceanic condition, however, the fishing gear and fishing method were undeveloped, so that, Japanese fishermen had been exploited fisheries resources penetrating the fishing ground. Most important species were lot of captured croaker, cod, spanish mackeral, sea abream, herring in coastal sea. nowaday, squid, anchovy, shrimp, crab, pompret were much captured. The species were captured in 18 century were not captured. It is rarely than that period. Fishereis aquatic culture had been not farmed till 1960 year, but sea laver, shrimp, crab, had been breeded 1970 year also, the fresh water fish e.g. eel, cat-fish had been breeded activately. The fisheries processing industry were composed of salt. icing, dry, method. the salted fish industry had been prevailed at Gangyng, Kwangchon, Kunsan, Julpo comparatively. The fisheries institute had been established at Kunsan at first, but institute established in other region had been abolished in a short time. This phenomenon was related with development of fisheries resources. The western coast fisheries industries had been wasted of decreasing of fisheries resources, variation of environment. Accordingly, the study of preserving the marine resources. educated man power who engaged in fisheries field have to accomplish. Sea was dying with reason of loss of mud in west coast factory waste, waste of life the increase of accident of sea polluted, each illegal fishing industry physical and chemical reason etc. in this respect, Kusan maritime college, fisheries developing agency, institute have to take important role for developing fishing industry.

• Fisheries and Aquatic Sciences
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• v.24 no.2
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• pp.89-98
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• 2021

The accumulation of ammonia, a consequence of intensive aquaculture activity, can damage cultured animals. We analyzed the survival rates, growth, antioxidant responses, and immune responses of abalones, Haliotis discus hannai (mean shell length 70.2 ± 4.9 mm; mean body weight 36.9 ± 3.6 g), biweekly for four weeks, to determine the accumulated concentrations of ammonia (0, 0.1, 0.2, 0.4, 0.8, and 1.6 mg/L). In our biweekly measurements, a survival rate of ≥ 95% was observed for all concentrations of ammonia. The specific growth rate (SGR) decreased at ≥ 0.8 mg/L (p < 0.05), but the daily increment in shell length (DISL) showed no significant change (p < 0.05). Regarding antioxidant responses, the superoxide dismutase (SOD) activity of the hepatopancreas was increased at ammonia concentrations over 0.8 and 0.2 mg/L (p < 0.05) at two and four weeks, respectively, and the SOD activity of the gills increased at concentrations over 0.4 and 1.6 mg/L (p < 0.05) at four weeks. The catalase (CAT) activity of the hepatopancreas and gills increased at ammonia concentrations > 0.8 mg/L (p < 0.05). Phenoloxidase (PO) activity increased at ammonia concentrations over 0.8 mg/L (p < 0.05), and Lysozyme (LZM) increased at concentrations over 0.8 and 0.4 mg/L (p < 0.05). Overall, our findings indicated that ammonia concentrations over 0.8 mg/L in seawater might damage the SGR, antioxidant responses, and immune responses in H. discus hannai. Our findings suggest the necessity of improvement or reinstallation for abalone aquaculture systems and can be used to assess the toxic effects of ammonia on H. hannai.