• Journal of Nutrition and Health
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• 제32권6호
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• pp.661-670
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• 1999

Effects of Ca supplementation on blood pressure(BP) response to dietary Na level were studied in 15 normotensive healthy college women with family history of hypertension. All subjects, randomly divided into 3 groups, ate low Na diet(1816mg/day) prepared in the laboratory during the first 2 weeks and normal Na diet(4064mg/day) of their own home for the next 8 weeks. The one group received daily 1g Ca supplement at both low and normal Na diet periods, the second group took daily 1g Ca supplement only at normal a diet period, and the last group took placebo during both periods. Average Ca and energy intakes at the basal of and during the trial ranged 450-600mg and 1735-1878kcal, respectively. Systolic/diastolic BP was decreased by 9.2-9.8/4.4-4.5 mmHg during low Na diet period and was increased again during next normal Na diet period. However simultaneous Ca supplementation during both low and normal Na diet period suppressed the elevation of systolic/diastolic BP occurred at normal Na diet period. Ca supplementation only at normal Na diet peroid did not affect the BP elevation. The increase of serum Ca and Ca/Mg ratio and the decrease of serum Na and Na/K ratio might be related to the BP lowering effects of Ca supplementation. In conclusion, Ca supplement could attenuate BP elevation induced by increasing Na intake. The BP lowering effect of Ca supplementation was not appeared at low Na intake. Further studies were needed to make it certain. Low Na intake was also confirmed as an effective diet control for lowering blood pressure.

• The Korean Journal of Physiology
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• 제21권2호
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• pp.179-189
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• 1987

Since it has been known that ryanodine has a potent negative inotropic effect on the cardiac muscle contractility (Jenden and Fairhurst, 1968), ryanodine has been a subject of intensive research (Frank and Sleator, 1975; Jones et al, 1978; Sutko et al, 1985). However, the underlying mechanism for the ryanodine dependent negative inotropic effect is still uncertain. In this study, the effects of ryanodine on the generation and relaxation of contracture due to Na-withdrawal and on the force-frequency relationship of heart muscles isolated from rats and guinea pigs were measured in an effort to understand the underlying mechanism of the ryanodine-induced negative inotropy. Results are summerized as follows: 1 ) Ryanodine significantly reduced the contractility of heart muscles produced at low frequency of stimulation, but showed a little effect on the contractility at high frequency stimulation. 2) Ryanodine, at the concentrations ranging from $10^{-6}\;M$ to $10^{-8}\;M$, had no significant effect on the Na-dependent relaxation of Na-withdrawl contracture. 3) Ryandoine significantly reduced the amplitude of the Na-withdrawl contracture, and this inhibitory effect was reinforced by procaine, antiagonized by caffeine and high potassium. From these results, it may be concluded that the negative inotropic effect of ryanodine is mainly due to an inhibition of calcium release from sarcoplasmic reticulum.

• 대한약침학회지
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• 제2권1호
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• pp.13-25
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• 1999

This study was undertaken to determine whether Juglandis Semen (JAS) extraction exerts protective effect against oxidant-induced inhibition of $Na^+$-pump activity in cerebral cortex. $Na^+$-pump activity was estimated by measuring ouabain-sensitive oxygen consumption. The oxygen consumption significantly inhibited by 1 mM t-butylhydroperoxide (tBHP), which was prevented by addition of 2% JAS extraction. The oxygen consumption was increased by an increase in $Na^+$ concentration from 5 to 100mM, $K^+$ concentration from 0.5 to 10 mM, and $Mg^{++}$ concentration from 0.2 to 5 mM. These changes in ion concentrations did not affect the inhibitory effct of tBHP and protective action of JAS on oxygen consumption. tBHP(1mM) produced a significant increase in lipid peroxidation in cerebral cortex, which was prevented by 2% JAS extraction. These result suggest that JAS exerts protective effect against tBHP-induced inhibition of $Na^+$-pump activity in the cerebral cortex, this effect may be due to by an antioxidant action.

• 한국미생물·생명공학회지
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• 제27권2호
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• pp.91-95
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• 1999

To investigate the effect of salts on the production of erythritol by Torula sp., cells were grown on the media containing various concentrations of KCl or NaCl. Cell growth and glucose consumption rates decreased when KCl or NaCl concentration increased from 0.0 to 0.5M. The production of erythritol, however, was maximal at 0.3M aCl. The erythritol concentration of 54.3g/l in the medium containing 0.3M NaCl and 200g/l glucose was obtained after 120h. The production of erythritol decreased in cultures above 0.3M NaCl or 0.4M KCl due to the inhibition of cell growth. To elucidate the effect of salts more quantitatively, KCl and NaCl concentrations were converted to osmotic pressure. As the osmotic pressure increased, the yield of erythritol from glucose increased regardless of the kinds of salts and the yield of erythritol was approximately 49% at the osmolality of 2.4Os/kg. When the osmotic pressure increased to 2.5Os/kg, the specific growth rate of cells decreased but the production rate of erythritol increased. For the effective production of erythritol, osmotic pressure must be adjusted not to inhibit markedly the growth rate of cells and to stimulate the production rate of erythritol by supplementing salt.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.1087-1092
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• 2001

The effect of Sodium Butyrate (NaBu) on the N-linked oligosaccharide structure of Erythropoietin (EPO) was investigated. Recombinant human EPO was produced by CHO cells grown in an $MEM{\alpha}$ medium with or without 5 mM NaBu, and purified from the culture supernatants using a heparin-sepharose affinity column and immunoaffinity column. The N-linked oligosaccharides were released enzymatically and isolated by paper chromatography. The isolated oligosaccharides were then labeled with a fluorescent dye, 2-aminobenzamide, and analyzed with MonoQ anion exchange chromatography and GlycosepN amide chromatography for the assignment of a GU (glucose unit) vague. A glycan analysis by HPLC showed that the most significant characteristic effect of NaBu was a reduction in the proportion of glycans with Sri-and tetrasialylated oligodaccharides from $21.30\%$ (tri-) and $14.86\%$ (tetra-) in the control cultures (without NaBu) to $8.72\%$ (tri-) and $1.25\%$ (tetra-) in the NaBu-treated cultures, respectively. It was also found that the proportion of asialo-glycan increased from $12.54\%\;to\;23.6\%$ when treated with NaBu.

• 한국식품영양학회지
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• 제7권2호
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• pp.151-158
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• 1994

This study was carried out to clear up the cause of low-acid producing phenomenon occurred In non-fat dry milk during liquid-yoghurt fermentation by Lactobacillus case, and to present its improving methods. All samples of non-fat dry milks which were low in TCA-soluble peptides showed low-acid production, but those high in TCA-soluble peptides showed high-acid production. The addition of trypsin-hydrolysate of Na-caseinate to non-fat dry milk showed some improving effect on acid production but that of papain-hydrolysate did not show any improving effect and that of bacterical neutral protease-hydrolysate showed some inhibitory effect. The improving effects on growth and acid production of lactic acid bacteria were more prominent when the trypsin-hydrolysate of Na-caseinate was added. to such fermenting system in which the levels of TCA-soluble peptides and the proteolytic ability of starter bacteria were abnormally low. The liquid-yoghurt made with non-hydrolysed Na-caseinate and defective non-fat dry milk showed precipitate occurrence but that with trypsin-hydrolysate of Na-caseinate and defective non-fat dry milk did not make any precipitate during storage as with normal non-fat dry milk.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.514-523
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• 2021

This study investigated the effect of anode fuel composition on the performance of direct borohydride/hydrogen peroxide fuel cells (DBHPFCs). The effect of sodium borohydride (NaBH₄) and sodium hydroxide (NaOH) concentrations on fuel cell performance was determined through fuel cell tests. Fuel cell performance increased with an increase in the NaBH₄ concentration, whereas it decreased with an increase in the NaOH concentration. The anode fuel composition was selected as 10 wt% NaBH₄+10 wt% NaOH+80 wt% H₂O based on the fuel viscosity, electrochemical reaction rate, and decomposition reaction rate. DBHPFCs were also tested to analyze the effect of operating temperature and operation time on fuel cell performance. The present results can be used as a reference basis to determine operating conditions of DBHPFCs.

• Journal of Ecology and Environment
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• 제39권1호
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• pp.81-90
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• 2016

This study was to investigate the effect of salt stress on physiological characteristics such as plant growth, photosynthesis, solutes related to osmoregulation of Beta vulgaris. A significant increase of dry weight was observed in 50 mM and 100 mM NaCl. The contents of Chl a, b and carotenoid were lower in NaCl treatments than the control. On 14 day after NaCl treatment, photosynthetic rate (P_N), the transpiration rate (E) and stomatal conductance of CO₂ (g_s) were reduced by NaCl treatment. On 28 day after NaCl treatment, the significant reduction in g_s and E was shown in NaCl 200 mM. However, P_N and water use efficiency (WUE) in all NaCl treatments showed higher value than that of control. Total ion contents (TIC) and osmolality were higher than the control. On 14 day after treatment, the contents of proline (Pro) increased significantly in 200 mM and 300 mM NaCl concentration compared with control, whereas on 28 day in all treatments it was lower than that of the control. The contents of glycine betaine (GB) increased with the increase of NaCl concentration. The contents of Na⁺, Cl^-, GB, osmolality and TIC increased with the increase of NaCl concentrations. These results suggested that under severe NaCl stress conditions, NaCl treatment did not induce photochemical inhibition on fluorescence in the leaves of B. vulgaris, but the reduction of chlorophyll contents was related in a decrease in leaf production. Furthermore, increased GB as well as Na⁺ and Cl^- contents resulted in a increase of osmolality, which can help to overcome NaCl stress.

• 한국유기농업학회지
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• 제22권2호
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• pp.347-357
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• 2014

본 연구는 배 개화기에 염소계 살균제인 NaDCC(sodium dichloroisocyanurate)의 사용에 따른 배검은별무늬병의 방제 가능성을 검토하기 위하여 수행하였다. 건전한 배나무에 배검은 별무늬병원균인 Venturia nashicola의 분생포자를 접종하고 NaDCC를 농도별로 살포한 결과, 무처리에서 51.6% 발생한 반면에 NaDCC 처리시 750mg/L에서는 23.8%, 1,000mg/L에서는 26.2%로 발병억제 효과가 있었다. 원황 등 6개 품종을 대상으로 만개기에 NaDCC를 살포하여도 배꽃의 화분발아에는 피해가 없었다. 신고 배 포장에서 개화초기와 만개기로 구분하여 NaDCC를 살포한 결과 개화초기에 NaDCC를 단독 살포 처리시 98% 이상의 높은 수정율을 나타내어 가장 효과적인 살포시기로 판단되었다. 또한 신고 배 재배포장에서 NaDCC를 배검은별무늬병 방제 적기에 4회를 살포한 결과 NaDCC 750mg/L 이상의 농도로 처리시 발병과율은 0%이었다.

• 농업과학연구
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• 제20권1호
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• pp.18-24
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• 1993

일반소독제로 광범위하게 사용되는 NaOCl을 종자소독제로써 이용할 수 있는 방안을 확립하고자 종자전염에 의한 병해 발생이 많은 볍씨와 채소종자를 대상으로 소독 효과를 조사하였던 바 다음과 같은 결과를 얻었다. 1. NaOCl의 참깨 종자 소독 효과를 조사하였던 바 NaOCl의 농도가 높을 수록 그리고 침지시간이 길수록 종자 소독 효과가 뚜렷 하였으나 종자 발아 장해를 일으켰다. 종자발아율을 높이며 소독효과가 우수한 종자 처리 방법은 NaOCl 1-2%에서 10분간 침지하는 것이었고, 벼 종자소독 효과는 NaOCl 농도 1-2%에서 침지시간을 30분 이내로 하는 것이 좋았다. 2. 무, 배추 종자 소독 효과를 조사하였던 바 NaOCl 농도 1%에서 10분간 침지할 경우 각종 Alternaria균의 검출율을 현저히 저하시켰고, 고추종자에서는 NaOCl 농도 1%에서 10분간 침지할 경우 각종 탄저병균의 검출율을 현저히 저하시켰다. 3. 종자전염성 진균에 대한 NaOCl의 소독 효과는 종자소독제인 Benlate T에 비하여 참깨종자에서는 우수하게 나타났고, 볍씨에서는 비슷하였다. 그러나 NaOCl은 처리농도가 높고 시간이 긴 경우에는 발아장해를 초래하였다.