• Journal of Life Science
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• v.23 no.11
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• pp.1342-1350
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• 2013

We examined the effect of hydrogen sulfide ($H_2S$) in chemical hypoxia-induced injury in mouse hepatocytes. Cell viability was significantly decreased by cobalt chloride ($CoCl_2$), a well-known hypoxia mimetic agent in a time- and dose- dependent manner. Sodium hydrosulfide (NaHS, a donor of $H_2S$) pretreatment before exposure to $CoCl_2$ significantly attenuated the $CoCl_2$-induced decrease of cell viability. $CoCl_2$ treatment resulted in an increase of intracellular ROS generation, which is inhibited by NaHS or N-acetyl-cysteine (NAC, a ROS scavenger), and p38 MAPK phosphorylation, which is also blocked by NaHS or NAC. The $CoCl_2$-induced increase of the Bax/Bcl-2 ratio was attenuated by NaHS, NAC, and SB 203580 (p38 MAPK inhibitor). The $CoCl_2$-induced decrease of cell viability was also attenuated by NaHS, NAC, and SB 203580 pretreatment. Additionally, NaHS inhibited the $CoCl_2$-induced COX-2. Similar to the effect of NaHS, NAC blocked $CoCl_2$-induced COX-2 expression. Furthermore, NS-398 (a selective COX-2 inhibitor) attenuated not only the $CoCl_2$-induced increase of the Bax/Bcl-2 ratio, it also decreased cell viability. Taken together, $H_2S$ protects primary cultured mouse hepatocytes against $CoCl_2$-induced cell injury through inhibition of the ROS-activated p38 MAPK cascade and the COX-2 pathway.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.2
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• pp.182-188
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• 1997

The study was carried out to determine an optimum concentration of plant growth regulators(ABA and kinetin) on reducing NaCl toxicity during germination in rice. Plant height of a japonica cultivar Ilpumbyeo in ABA 10$^{-5}$ M was increased, while all treatments of kinetin had no clear effects on increasing the plant height. However, other rice cultivars showed slightly different reaction by PGRs compared with Ilpumbyeo. Germination rate of four rice cultivars was ranged from 53.1 to 58.2％ in NaCl 1.3％. All treatments of kinetin accelerated germination rate of tested rice cultivars except Dasanbyeo compared with NaCl 1.3％ treatment. The higher concentration of ABA and kinetin treatment induced the higher starch content, and while the lower concentration of two plant growth regulators induced the higher sugar content in all four rice cultivars. The free proline content of rice seedlings was highest in Ilpumbyeo among the tested cultivars under NaCl 1.3％ treatment.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.317-323
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• 2010

This study aimed to examine a suppression effect of salinity on extension rate of stem elongation of cucumber seedlings (Cucumis sativus L.) grafted with roots of figleaf gourd plant. The effects of application methods, timings, and concentrations of two salt types, sodium chloride (NaCl) and calcium chloride ($CaCl_2$), were compared to untreated control plants. In result, an obvious suppression effect on the excessive elongation of stem was obtained by both sub-irrigated and medium-mixed NaCl salt. An improvement in quality of transplants was also obtained by the sub-irrigated NaCl salt. Foliar-applied NaCl caused visible leaf injury when the concentration was higher than 40 mM; but, with no effect on suppressing the stem elongation. When the NaCl was applied at 7 days after grafting, a higher concentration of NaCl was demanded for suppressing the stem elongation compared to an application at the day of grafting. No effect of the NaCl salt on the fresh weights of 36-day grown plants was observed; but, there was a negative effect on the number of female flowers at a high temperature season. Overall, the NaCl salt was more effective on slowing down the stem elongation and had the lower incidence of leaf injury than the $CaCl_2$ salt.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.352-358
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• 2006

We investigated the mechanism on occurring of briny injury in four fruit species (apple, pear, grape, peach). Briny injury of apple, pear, peach, and grape was induced by the foliar splay of saline solutions. Browning symptom was initiated one hour after the spray of 3% NaCl in apple, pearl and peach trees. while two hour were needed for grape, but the latter developed the symptom faster than the formers. Foliar spray of 3% NaCl resulted in 4-fold increase in ethylene production 24 h after the spray, and the production was returned to early stage rate after 72 h. Ethylene production of control was nearly constant with slight decrease after 4 h. Browning and defoliation response to the spray of 3% NaCl on lower side were not different from the spray on both sides regardless of fruit species, while no injury symptoms occurred by the spiny on upper side. In saline damage for treated date, lateral bud was only germinated in apple at 30 July. A shoot apex was 100% grew in all fruit tree. In result for hormonal content of leaf and shoot apex, control was high t-zeatin content in leaf. However, IAA and ABA content was increasing in high saline concentration.

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.296-300
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• 1998

The analysis of biochemical changes in tobacco plant as increase of NaCl concentraion was conducted. Total protein content and soluble protein content were decreased as NaCl concentration was increased, in that steady decreased until 120mM NaCl and largely decreased at 150mM NaCl. The expression of 74Kd subunit was increased until 60mM NaCl. However, the amount of 74Kd protein was decreased from 90mM NaCl. There was no difference for expression of other protein subunits. Chlorophyll a content was significantly decrease as NaCl concentration was increased, but chlorophyll b content was not much decreased. The slow increase up to 120mM NaCl and large increase at 150mM NaCl for ATPase and peroxidase activities indicated that 120mM NaCl could be a limiting concentration for salt injury.

• Journal of Life Science
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• v.18 no.2
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• pp.154-161
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• 2008

The physiological and photochemical responses of rice seedling to NaCl stress were investigated through measuring leaf relative water content (RWC), root water uptake and chlorophyll fluorescence. When plants were exposed to increased salinity stress, the visual symptoms of injury were significant at ${\geq}$500 mM NaCl concentration for 4 and 5 day stress periods. The differences in Fv/Fm between control treatment and plants treated with 500 mM and 1,000 mM NaCl were evident after 5 day and 4 day, respectively, whereas in root water uptake its effect was observed at 500 mM and 1,000 mM NaCl at 2 day of salt-stressed periods. Leaf RWC in salt-stressed plants decreased gradually with increasing salinity in exogenous solution and duration of salt stress, and these decrease showed leaf RWC of 58-68% atduration over 2 day stress of 1,000 mM NaCl treatment and 88% at 1 day stress. NaCl stress led to a significant inhibition of the light-induced greening in etiolated rice plants, especially in 4 and 5 day salt-stressed plants, which linearly decreased with NaCl concentration ($R^2$=0.812 and 0.918, respectively). The effects of NaCl stress in rice seedlings indicate that water uptake in root is more sensitive to increasing NaCl concentration and stress duration than Fv /Fm in leaves compared with the same NaCl concentration.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.368-372
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• 2009

The viability of Staphylococcus aureus, a significant cause of food poisoning in Korea, on TSA plates was determined after sublethal heating treatments and NaCl treatments. In addition, recovery levels of sublethally injured cells on TSA plates containing different concentrations of NaCl (TSAS) were investigated. The viability decreased significantly with increasing degree of sublethal heating treatments, but increases in NaCl treatment concentrations from 0 to 6% had little effect on the viability. After being sublethally treated at $55^{\circ}C$ for 30 min, bacterial populations were reduced by 7.91, 7.97 and 7.99 log CFU/mL on 2, 4 and 6% TSAS, respectively. After being sublethally treated at 60oC for 30 min, bacterial populations were reduced by 6.46, 6.47 and 6.48 log CFU/mL on 2, 4 and 6% TSAS, respectively. Decimal reduction times (D-value) decreased with increasing NaCl treatment concentrations after sublethal heating at 55 and $60^{\circ}C$. These data imply that the S. aureus cells sublethally injured by insufficient heating processes had a lower recovery rate with increasing NaCl concentrations in the recovery media.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.720-723
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• 2006

The viability of Shigella sonnei, a significant cause of gastroenteritis in Korea, on TSA plates was determined after sublethal heating treatments and NaCl treatments. In addition, recovery levels of sublethally injured cells on TSA plates containing different concentrations of NaCl (TSAS) were investigated. The viability decreased significantly with increasing degree of sublethal heating treatments, but increases in NaCI treatment concentration from 0 to 6% had little effect on the viability. After being sublethally treated at $55^{\circ}C$ for 30 min, bacterial populations were reduced by 7.58, 7.83 and 7.93 log CFU/mL on 2, 4, and 6% TSAS, respectively. After being sublethally treated at $60^{\circ}C$ for 30 min, bacterial populations were reduced by 6.71, 6.73, and 6.73 log CFU/mL on 2, 4 and 6% TSAS, respectively. Decimal reduction times (D-values) decreased with increasing NaCl treatment concentrations after sublethal heating at 55 or $60^{\circ}C$. These data imply that the S. sonnei cells sublethally injured by insufficient heating processes had a lower recovery rate with increasing NaCl concentrations in the recovery media.

• Korean Journal of Weed Science
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• v.32 no.1
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• pp.35-43
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• 2012

The objective of this research was to confirm the difference in physiological responses to environmental stresses such as chilling, high temperature, NaCl, and chemical stress (paraquat) in Protox inhibitor resistant-transgenic rice (MX, PX, and AP37) and its non-transgenic counterpart (WT). Transgenic and non-transgenic rice plants were exposed to a chilling temperature of $5^{\circ}C$ for 1 day or a high temperature of $45^{\circ}C$ for 4 days and allowed to recover at $25^{\circ}C$ for 6 days after the chilling treatment or 8 days after the high temperature treatment. Leaf injury, shoot fresh weight, porphyrin biosynthesis substances, and chlorophyll content were investigated in transgenic and non-transgenic rice at 6 days after 0.5% and 1% NaCl treatments or at 5 days after 0~300 ${\mu}M$ paraquat treatments. No significant difference in leaf injury and shoot fresh weight were observed between transgenic and non-transgenic rice during chilling and recovery. Plant height and shoot fresh weight were also similar between transgenic and non-transgenic rice during the high temperature and recovery period (0~5 days). However, plant height and shoot fresh weight in transgenic rice line MX and PX were lower than in non-transgenic rice at 6 days for recovery. Leaf injury, chlorophyll, and Mg-Proto IX ME contents had no significant difference between transgenic rice and non-transgenic rice after NaCl treatment, but Proto IX content for AP37 and shoot fresh weight for PX and AP37 in 0.5% NaCl treatment were significantly reduced compared with non-transgenic rice. There was no difference in leaf injury and shoot fresh weight when comparing transgenic rice and non-transgenic rice after paraquat treatment. Although transgenic rice and non-transgenic rice showed a little difference at a particular measurement period in certain environmental stresses, there was generally no difference in physiological responses between transgenic rice and non-transgenic rice.

• Journal of Acupuncture Research
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• v.18 no.2
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• pp.101-110
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• 2001

Objective : This study was undertaken to determine if Scutellaria baicalensis Georgi (SbG) extract exerts protective effect against oxidant-induced cell injury in renal proximal tubular cells. Methods : The cell injury was evaluated by lactate dehydrogenase (LDH) release in rabbit renal cortical slices and lipid peroxidation was estimated by measuring malondialdehyde (MDA). t-Butylhydroperoxide (tBHP) was used as a model of oxidant. Results : tBHP at 1 mM increased LDH release and lipid peroxidation, which were prevented by SbG in a dose dependent manner over concentration range of 0.001-0.1%. SbG provided the protective effect against oxidant-induced reduction in PAH uptake by renal cortical slices and microsomal Na+-K+-ATPase activity. SbG attenuated tBHP-induced depletion of reduced glutathione. 0.2 mM $HgCl_2$ increased LDH release and lipid peroxidation, which were completely prevented by 0.05% SbG. Conclusion : SbG prevents oxidant-induced impairment in membrane transport function.