• Development and Reproduction
• /
• v.24 no.3
• /
• pp.215-224
• /
• 2020

Seawater adaptability of steelhead trout increases along with the increase in the size of the fish, independent of parr-smolt transformation. Three 96 h seawater challenge tests were conducted to determine the size at which seawater adaptability of steelhead trout develops. Plasma Na⁺ and Cl^- levels, moisture content, gill Na⁺/K⁺ ATPase activity, and mortality during the 96 h after direct transfer to seawater (32 ppt) were determined. Plasma Na⁺ and Cl^- levels in 50 g fish continuously increased during the 96 h after the transfer to seawater (p<0.05), but the levels in 100 and 150 g fish leveled off after 24 h (p<0.05). Both 100 and 150 g size steelhead trout maintained muscle moisture content (%) better than 50 g size fish (p<0.05). Gill Na⁺/K⁺ ATPase activity in the 100 g size group increased in a time-dependent manner after transfer to seawater (p<0.05), whereas activity in the 50 and 150 g sizes did not increase (p>0.05), for which a possible explanation was discussed. A mere 2.6% mortality in both the 50 and 150 g size groups was observed. In conclusion, the current results indicate that 50 g size steelhead trout did not show development of a high level of hypoosmoregulatory capacity, whereas fish in the 100 and 150 g size groups showed a high level in our experimental conditions. Therefore, the steelhead trout larger than a 100 g size is recommended for transfer to seawater culture.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.25 no.2
• /
• pp.73-78
• /
• 1992

To investigate the desirable index for evaluation of frozen surimi's grades, the relationship between indices for grading of surimi, such as ATPase activity $(Ca^{2+}-,\;Mg^{2+}-\;and\;EDTA-)4, solubility, viscosity and K-value of frozen surimi and jelly strength of kamaboko was studied. The myofibrillar $Ca^{2+}-ATPase$ activity and solubility from frozen surimi of grades SA, FA, A, RA and B gave values of $1.184\pm0.2,\;0.956\pm0.14,\;0.766\pm/0.07,\;0.453\pm0.07\;and\;0.227\pm0.08$(umoles Pi/min/mg) for $Ca^{2+}-$ATPase activity and $93.19\pm5,\;84.62\pm4,\;70.63\pm5,\;41.21\pm4\;and\;32.82\pm4(\%)$ for solubility, respectively. Therefore, the myofibrillar $Ca^{2+}-$ATPase activity and solubility of surimi were closely related to the jelly strength of kamaboko from same material, as the correlation coefficient were 0.9584 and 0.9849, respectively. K-value, the index of freshness, was related to the jelly strength of frozen surimi as the correlation coefficient 0.9053 and shown as SA $15.67\pm1.4,\;FA\;14.94\pm 3,\;A\;28.00\pm5,\;RA\;32.16\pm3\;and \;B\;48.68\pm 5(\%)$. $Mg^{2+}-$ and EDTA-ATPase activity and viscosity were not related to the jelly strength. The $Ca^{2+}-$ATPase activity and solubility were found to be useful index for evaluating the quality of frozen surimi.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1994.04a
• /
• pp.302-302
• /
• 1994

오메프라졸의 산 불안정성을 개선하기 위하여 신규 합성한 오메프라졸 cholestyramin resin 염 복합체와 오메프라졸 hydroxypropyl-$\beta$-cyclodextrin (HP-$\beta$-CD) 포접화합물의 약효를 검색하였다. 생체외 실험 (in vitro test)으로 H$^{+}$/K$^{+}$-ATPase 활성도 저해효과를 검토하였으며 생체내 실험 (in vivo test)으로 Shay 결찰법에 의한 위산분비 억제효과에 대한 실험을 실시하였다. 오메프라종 염 복합체와 오매프라졸 포접화합물은 1$\times$$10^{-5}$-1$\times$$10^{-3}$M농도 범위에서 용랴의존적으로 H$^{+}$K$^{+}$-ATPase 활성을 억제시켰으며 $IC_{50}$/치는 오메프라졸 결과와 유사하였다. 셍체네 실험에서는 오메프라졸 HP-$\beta$-CD 포접화합물이 오메프라졸과 그 resin염복합체보다 위액분비량, 펩신 활성도에 대한 $IC_{50}$/치가 낮았으며 이는 생체내에서 포접 화합물이 오메프라졸의 안정성을 증가시킴으로서 위산분비 억제효과를 증가시킨것으로 사료된다.

• Journal of the Korean Chemical Society
• /
• v.40 no.10
• /
• pp.674-677
• /
• 1996

• Proceedings of the Korea Crystallographic Association Conference
• /
• 2003.05a
• /
• pp.16-16
• /
• 2003

Mismatches in a DNA duplex are mainly due to DNA duplication errors that are generated by improper function of DNA polymerase. MutS, MutL and MutH are crucial proteins for the initiation of the methyl-directed mismatch repairing in bacteria. MutS has an ATPase activity md recognize the mismatched or unpaired bases on DNA. After binding to a mismatch, MutS recruits MutL to mediate the activation of MutH an endonuclease, which cleaves the 5' site of d(GATC) on the un-methylated strand. Both MutL and MutS also have essential roles in the subsequent removal and re-synthesis of the daughter strand. We have determined the crystal structures of either intact or active fragments of each of these proteins, both alone and complexed with ligands (DNA, ADP and ATP). The biochemical and mutagenesis studies based on the detailed 3-D structures led to new insights into the role of the ATPase activity of MutS in the mismatch recognition and directions for future investigation of mismatch repair.

• Food Science of Animal Resources
• /
• v.27 no.4
• /
• pp.457-462
• /
• 2007

Effects of sonication on water-solubilization of myofibril from breast muscle of spent hen effects investigated in this study. To evaluate effect of salt concentration and pH, salt concentration was varied with range from 0.1 to 0.8 M, and pH was varied with range from 6.0 to 8.0. Solubility, SDS-PAGE, viscosity and ATPase activity of sonicated myofibril were measured. Solubility of myofibrillar protein containing 0.1 M NaCl at pH 8.0 after sonication was above 90%. Main components of soluble protein by SDS-PAGE were myosin heavy chain and actin. That is, it indicated breaking of myofibril structure by sonication. Also, viscosity of soluble protein increased, but Ca- and Mg-ATPase activities decreased by increasing sonication time. From these results, we concluded that most of myofibrillar proteins were denatured by sonication.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.10
• /
• pp.1500-1509
• /
• 2014

The object of this study was to investigate the inhibitory effects of chios mastic gum (MG) on gastric acid secretion in an ethanol-induced SD rat model and primary parietal cells. Rats were randomly divided into four groups: Vehicle (normal group), Control (treated with ethanol), MG50 (treated with ethanol and mastic gum at 50 mg/kg b.w), MG100 (treated with ethanol and mastic gum at 100 mg/kg b.w). Groups treated with both MG50 and MG100 showed attenuation of gastric mucosal injury, sub-epithelial loss, hemorrhaging, and gastric juice secretion. We also examined the acidity of gastric juice during gastric injury. Oral administration of both MG50 and MG100 significantly decreased acidity of gastric juice by % and %, respectively. To examine the stimulatory factors related to gastric acid secretion, mRNA expression levels of H2r, M3r, CCK2r, and $H^+/K^+$ ATPase were measured by real-time PCR. Compared with a vehicle group, mRNA expression levels of H2r, CCK2r, and $H^+/K^+$ ATPase clearly increased in the control group. However, levels of H2r, CCK2r, and $H^+/K^+$ ATPase slightly but significantly decreased in MG-treated groups compared with control. Blood level of histamine significantly decreased in MG-treated groups, which indicates the involvement of MG on in histamine-related acid secretion. To identify the mode of action of MG in regulating histamine-related pathways, intracellular level of cAMP and mRNA levels of H2r, M3r, CCK2r, and $H^+/K^+$ ATPase were measured in primary parietal cells. While mRNA levels of M3r and CCK2r remained unchanged, levels of H2r and $H^+/K^+$ ATPase significantly decreased upon MG treatment. Subsequently, intracellular levels of cAMP decreased. These results suggest that mastic gum has the ability to inhibit gastric acid secretion by regulating a histamine-related pathway.

• Microbiology and Biotechnology Letters
• /
• v.26 no.2
• /
• pp.102-109
• /
• 1998

To investigate the increased acid tolerance of a acid-resistant mutant Leuconostoc mesenteroides M-100 improved as a kimchi starter, proton permeability, ATPase acitivity, glycolysis activity, $Mg^{2+}$ releasement, and membrane fatty acid composition were studied and comprised with its wild type Leuconostoc mesenteroides Mw. In the proton permeability experiment, the mininum values of the average half time ($t_{1/2}$) of pH equilibration through the cell membrane of the Mw and the M-100 were about 8.6 min and 9.2 min in 150 mM KCI solution, respectivily. In the 3% NaCl solution, the $t_{1/2}$ values of the Mw and the M-100 were 6min and 8.6 min, respectivily. The values and pHs of maximal specific activities of ATPase originated from the Mw and the M-100 were 0.6U at pH 5.5 and 0.8U at pH 5.5, respectivily. The result of pH dependence of glycolysis showed that the M-100 had higher activities than that of Mw except at pH 5.0. The releases of magnesium from the Mw and the M-100 were observed about 36.5% and 13% at pH 4.0 after 2 hours, respectivily. The results of comparison of membrane fatty acid composition of the Mw with the M-100 showed that $C_{12}$, $C_{14}$, $C_{18:1}$, and $C_{19:0cyclo}$ were major different fatty acids between two strains and the content of $C_{18:1}$, and $C_{19:0cyclo}$ were 23.4%, 10.2% in the Mw and 15.1%, 12.2% in the M-100. These results indicated that acid tolerance of the M-100 was significantly improved in comparison with its wild type Mw.

• Biomolecules & Therapeutics
• /
• v.7 no.4
• /
• pp.362-370
• /
• 1999

Propolis, a natural resinous compound collected from honey bees, contains many biochemical constituents(wax, flavonoids, phenolic compounds, etc.) and has been used in traditional medicines as early as 300 B.C. It was been demonstrated that ethanol, acetylsalicylic acid, ischemia reperfusion, non-steroidal antiin-flammatory drugs and stress induce gastric lesions by promoting the generation of reactive oxygen metabolites. Therefore, some drugs that are capable of scavenging or inhibiting the generation of reactive oxygen radicals might be expected to prevent the gastric mucosal injury. The aim of this study was 1) to examine the antiulcer effect of propolis, 2) to investigate the mechanism of action by determining gastric acid secretion, lipid per-oxidation, mucus content and proton pump ($H^+$/$K^+$-ATPase) activity on gastric mucus in varios experimental models, and finally, 3) to isolate and identify the pure compounds that exert antiulcer activity. Step 2-1 and 2-3 sub-sub fraction shoed a significant reduction of severity of gastirc damage at the dose of 25 mg/kg in various experimental models. We isolated 4 sub-sub-sub fractions by flash column chromatography of Step 2-1 sub-sub fraction and one sub-sub-sub fraction by recrystalization of Step 2-3 sub-sub fraction. The protective effects of propolis sub-sub-sub fraction manifested sifnificant effects in HCl-ethanol induced gastric erosion model and aspirin induced gastric ulcer model. These results showed that the gastric mucosal protective effect of propolis might result from the increase of mucus secretion, free radical scavenging effect as well as the reduction of acid secretion in accordance with the reduction of $H^+$/$K^+$-ATPase activitv. Three compounds were isolated and identified from sub-sub fraction of propolis which showed antiulcer effects. Subsequently, these compounds were identified as a flavonoid, namely, 2-acetoxy-5,7,-dihydroxy-flavanone, galangin and chrysin.

• Journal of Food Hygiene and Safety
• /
• v.14 no.4
• /
• pp.358-364
• /
• 1999

Propolis, a natural resinous compound collected from honey bees, contains many biochemical constituents and has been used in traditional medicines as early as 300 B.C. Recently, it has been reported to possess many biological activities such as antibacterial, antiviral, fungicidal, local anaesthetic, immunostimulating, antiinflammatory and free radical scavenging properties. This study was performed to investigate the pharmacological effects of the propolis extract and fractions on the gastric lesion and ulcer. The ethanol extract was fractionated with hexane, toluene and ethyl acetate. Followed by bioassay on antigastric and antiulcer activity. Propolis ethanol extracts(500, 750, 1,000, 1,500 and 2,000 mg/kg) showed the protective effect on HCl·ethanol-induced gastric lesion and the antisecretory effect against Shay’s gastric secretion in pylorus-ligated rats in a dose related manner. In the animal models of HCl·ethanol, aspirin-induced gastric lesion and Shay’s gastric secretion, the hexane and toluene fraction of propolis significantly reduced the length of gastric lesion and the acid secretion. These data showed that the gastric protective effects of propolis might result from reduction of acid secretion through the inactivation of H+/K+ATPase activity.