• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.712-718
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• 2004

This study was carried out to separate the calcium-binding protein derived from enzymatic hydrolysates of cheese whey protein. CWPs (cheese whey protein) heated for 10 min at $100^{\circ}C$ were hydrolyzed by trypsin, papain W-40, protease S, neutrase 1.5 and pepsin, and then properties of hydrolysates, separation of calcium-binding protein and analysis of calcium-binding ability were investigated. The DH (degree of hydrolysis) and NPN (non protein nitrogen) of heated-CWP hydrolysates by commercial enzymes were higher in trypsin than those of other commercial enzymes. In the result of SDS-PAGE (sodium dodecyl sulphate polyacrylamide gel electrophoresis), $\beta$-LG and $\alpha$-LA in trypsin hydrolysates were almost eliminated and the molecular weight of peptides derived from trypsin hydrolysates were smaller than 7 kDa. In the RP-HPLC (reverse phase HPLC) analysis, $\alpha$-LA was mostly eliminated, but $\beta$-LG was not affected by heat treatment and the RP-HPLC patterns of trypsin hydrolysates were similar to those of SDS-PAGE. In ion exchange chromatography, trypsin hydrolysates were shown to peak from 0.25 M NaCl and 0.5 M NaCl, and calcium-binding ability is associated with the large peak, which was eluted at a 0.25 M NaCl gradient concentration. Based on the results of this experiment, heated-CWP hydrolysates by trypsin were shown to have calcium-binding ability.

• 한국동물학회지
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• 제32권1호
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• pp.40-47
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• 1989

계배 근원세포의 배양 배지에 calcium ionophore A23187이나 EGTA를 배양 24시간에 첨가함으로서 초래된 세포내 칼슘 농도의 변화는 근원세포의 분화과정에 상당한 영향을 미쳤다. 배양 24시간에 A23187이나 EGTA를 첨가한 후 배양 48시간, 72시간, 및 96시간에 각각 세포를 [35S]methionine으로 1시간 표지시킨 후 수확하여 2차원 전기영동법으로 단백질을 분리시켰을 때, 일부 단백질은 배양 조건에 따라 합성 양상을 달리함을 보였다. 배양 24시간에 처리한 A23187과 calcium-activated neutral protease는 대조군에 비해 세포융합을 촉진시켰으나 동일 시기에 처리된 phosphoprotein을 정량함으로써 조사하였을 때, A23187이 배양 초기에는 대조군에 비해 약간 이 효소의 활성도를 높이는 효과를 보였으나 세포융합이 완성된 시기인 96시간에는 대조군에 비해 활성도를 높이는 효과를 보였으나 세포융합이 완성된 시기인 96시간에는 대조군에 비해 활성도의 차이를 나타내지 않았다. A23187 및 calcium-activated neutral protease에 의한 세포융합의 촉진, 그리고 A23187에 의한 protein kinase C 활성도의 증가가 모두 근원세포의 융합이 활발히 진행되는 시기인 배양 48-72 시간에 관찰됨을 볼 때, 세포내 칼슘의 농도는 protein kinase C 및 calcium-activated neutral protease와 상호연관을 가지면서 세포분화에 관여하는 것으로 사료된다.

• 한국식품저장유통학회지
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• 제22권2호
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• pp.297-302
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• 2015

저활용 단백질로부터 칼슘 결합물질을 분리하기 위해 돼지 육골분과 진주담치 단백질을 단백질 분해 효소인 alcalase를 이용하여 가수분해물을 제조하였고, 체내 흡수가 용이한 3 kDa 이하로 한외여과 하였다. 돼지 육골분 가수분해물은 Mono Q 컬럼을 통해 분리하였고, 진주담치 가수분해물의 경우 Q-Sepharose로 분리 하여 각각 2개, 3개의 peptide fraction을 얻어 각 fraction의 칼슘 결합력을 측정하였다. 그 결과 MBM F2와 Mussel F3에서 가장 높은 칼슘 결합력을 나타내었고, 따라서 본 연구 결과로 얻어진 가수분해물들은 칼슘 보충 소재로 활용될 수 있다고 판단된다.

• 한국식품영양과학회지
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• 제26권5호
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• pp.936-942
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• 1997

The present study was carried out to investigate the effects of dietary protein and magnesium levels on calcium and magnesium metabolism in male Sprague-Dawley rats. Forty-eight male rats(average weight, 210g) divided into six diet groups; protein 8% and Mg-free diet, protein 8% and Mg 400mg/kg diet, protein 8% and Mg 900mg/kg diet, protein 20% and Mg-free diet, protein 20% nd Mg 400mg/kg diet, and protein 20% and Mg 800mg/kg diet group. After the rats were fed with experimental diets concentration were examined. Kidney weight was significantly higher in protein 8% and Mg-free group compared with other groups. Serum calcium concentration of protein8% group tended to decrease with the increase of the level of magnesium. Serum magnesium concentration in protein 8% and 20% group was lower in Mg-free group than that in other groups(p<0.05) and it also increased as the dietary magnesium level was increased. Urinary calcium and magnesium concentration in Mg-free group were significantly lower than those of other groups.

• Journal of Nutrition and Health
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• 제28권10호
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• pp.986-994
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• 1995

This study was to examine the effect of phytate on the protein digestibility and calcium, iron and zinc availability in phytase treated soymilks digested with pepsin and pepsin-pancreatin in vitro. Also, the bending between phytate and protein in soymilks was investigated by means of SDS-PAGE. The content of phytate in soymilk was reduced by phytase treatment. As the content of phytate decreased, the protein digestibility increased in soymilk treated with the digest enzymes in vitro. The reduction of phytate content in soymilk improved the availability of all calcium, iron and zinc. Although the availability of calcium increased, the amount of change was small. The phytate reduction increased most the availability of iron. A number of bands of high molecular weight protein in soymilk disappleared in SDS-PAGE by lowering the phytate content with phytase treatement on soymilk.

• 대한가정학회지
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• 제30권1호
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• pp.99-113
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• 1992

This study was performed to investigate the effect of dietary protein and calcium levels on cadmium detoxication in rats. Seventy male Sprague-Dawley rats weighing 208 $\pm$ 19 g were blocked into 10 groups of 7 animals according to body weight. Five groups were fed 15% protein-0.6% calcium diet with 100ppm cadmium in drinking water for first 15days and the other 5groups fed same diet without cadmium in drinking water for same period and served as controls. After this 15-day intoxication period, each one of cadmium intoxication and control groups were fed each of 4 kinds of detoxifying diets different with protein(40%, 15%) and calcium(1.3%, 0.6%) levels without cadmimum in drinking water for following 15 days of detoxifying period. Results were summarized as follows: 1) Food intake, body weight gain, F.E.R. and weights of liver, kidney and femur were increased by detoxifying diets and high protein diet was most effective in weight gains of liver and kidney. 2) When cadmium and metallothionein contents of initial intoxication group and those of all detoxication groups were compared, cadmium and metallothionein contents in the liver were not changed, but those in kidney increased, and those in intestine decreased markedly. 3) Only dietary protein level affected cadmium and metallothionein distribution among organs, and cadmium contents of whole blood, liver, kidney and femur were lower in high protein diet, but metallothionein contents in liver and kidney were higher in high protein diet. 4) Gel filtration chromatogram showed that most of cadmium in the cytosol was bound to metallothionein fractions in high protein-high calcium group. Results obtained indicated that high protein diet was effective in cadmium detoxication by increasing the induction of metallothionein synthesis. But high calcium diet did not play a role in cadmium detoxication.

• Archives of Pharmacal Research
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• 제22권2호
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• pp.119-123
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• 1999

Parathyroid hormone (PTH) treatment of bone and kidney-derived cells not only activates adenyly cyclase buy also increases intracellular free calcium, and translocates protein kinase C (PKC) from cytosol to plasma membranes. We have found that acute phorbol ester pretreatment significantly decreases PTH-induced calcium transients and the effect of phorbol ester was antagonized by staurosporine (ST). Although the major effect of ST in that study was the reversal of the action of phorbol ester, it appeared that ST may also have promoted the effect of PTH directly. To further investigate the observation, we examined the effect of ST on the intracellular calcium transients induced by PTH and $\alpha$-thrombin ($\alpha$-TH). For calcium transient experiments, UMR-106 cells were loaded with 2 mM fluo-acetoxymethylester for 30 min at room temperature. The cells were then washed and suspended in buffer containing 1 mM calcium. Fluorescence was detected at 530 nm, with excitation at 505 nm. ST alone did not cause calcium transients, but enhanced the transients elicited by PTH response. added 5 min before the hormone. Another protein kinase inhibitor H-7 likewise enhanced the calcium responses elicited by PTH, while genistein did not affect PTH response. Calcium transients elicited by $\alpha$-TH were also enhanced by ST. The results suggest that there might be tonically activated endogenous protein kinase(s) which inhibit calcium signaling of some calcemic agents.

• 한국식품조리과학회지
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• 제19권2호
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• pp.216-222
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• 2003

The effects of hydrolysis times and calcium source additions (calcium lactate, calcium carbonate), on the qualify characteristics of soy ice cream prepared with soy protein isolate(SPI), were studied. Increasing the hydrolysis time decreased the viscosity and overrun of soy ice creams, but increased the melt-down property. The addition of calcium lactate increased the viscosity of the soy ice cream mix, but no changes were observed from the calcium carbonate addition. The overrun of calcium lactate samples was higher than on addition of calcium carbonate. The addition of calcium lactate and calcium carbonate resulted in decreased melt-down properties, although these effects were more evident in the calcium lactate samples. However, calcium carbonate addition resulted in higher scores in the overall quality of the soy ice creams. In conclusion, better soy ice cream could be prepared by treating the SPI with Flavorzyme for 50 min, along with calcium fortification in the form of calcium carbonate.

• 대한수의학회지
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• 제48권3호
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• pp.243-250
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• 2008

A calmodulin-dihydrofolate reductase (DHFR) sandwich fusion protein was generated by insertion of calmodulin into the $\beta$-bulge region of DHFR to observe the effects of structurally constraining the calmodulin structure. The calcium binding properties of the sandwich protein were almost identical to calmodulin. Similar to calmodulin ($10.7 {\mu}M$), the sandwich protein bound four equivalents of calcium, with half saturation ($K_{0.5}$) observed at a [$Ca^{2+}$] of $8{\mu}M$. However, nicotinamide adenine dinucleotide (NAD) kinase activation property of the sandwich protein was lower than that of calmodulin. The sandwich protein activated NAD kinase, but to only half of the level obtained with calmodulin. The K 0.5 for both calmodulin and the sandwich protein were approximately the same (1-2 nM). Methylation analyses of the sandwich protein show that insertion of calmodulin into DHFR results in a large decrease in methylation. The $V_{max}$ observed with the sandwich protein (95 nmole/min/ml) was only 22% of the value observed with calmodulin (436 nmol/min/ml) in the presence of calcium. Addition of trimethoprim to the reaction significantly inhibited the observed methylation rate. Overall, the data suggest that the insertion of calmodulin into the DHFR structure has little effect on calcium binding by the individual lobes of calmodulin, but may constrain the lobes in a manner that results in altered interaction with the calmodulin-dependent proteins, and severely perturbed the methyltransferase recognition site.

• Journal of Nutrition and Health
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• 제15권4호
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• pp.235-241
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• 1982

식이단백질(食餌蛋白質)과 칼슘의 섭취량(攝取量)이 뇨중(尿中) 칼슘 배설량(排泄量)에 미치는 영향을 검토하기 위하여 7명의 백인성인남자(白人成人男子)를 연구대상자(硏究對象者)로 하여 실험하였다. 연구대상자가 7 일동안 섭취한 식이(食餌)의 측량(測量) 기록(記錄)에 의거하여 단백질(蛋白質)(동물성(動物性) 및 식물성(植物性)), 칼슘과 인(燐)의 1 일평균(日平均) 섭취량을 분석하고 24시간의 뇨중(尿中) 칼슘양을 분석하였다. 단백질(蛋白質)과 칼슘의 1 일평균(日平均) 섭취량은 각각 103g과 1,237mg이었다. 뇨중 칼슘의 24시간 배설량은 식이(食餌)에 따라 다양하여 121mg부터 258mg에 달하였다. 모든 실험대상자의 단백질섭취량(蛋白質攝取量)을 4단계로 나누었을 때 : 저(低)(53g), 중(中)(87g), 상(上)(117g)과 고(高)(153g)이었으며, 이때 뇨중 칼슘배설량은 179mg, 189mg. 184mg과 264mg이었다. 단백질(蛋白質) 섭취수준이 고(高)로 증가함에 따라 뇨중칼슘양은 현저히 증가되었다. 특히 동물성단백질 섭취량이 뇨중칼슘양에 영향을 주는 것으로 나타났으며 식물성단백질 섭취량은 유의한 영향을 미치지 않았다. 한편 식이(食餌)칼슘의 1 일평균(日平均) 섭취량을 4단계로 나누었을 때 : 저(低)(544mg), 중(中)(842mg), 상(上)(1,232mg)과 고(高)(1,834mg) 이었으며, 이때 뇨중칼슘 배설량은 169mg, 196mg, 222mg 과 197mg이었다. 식이칼슘 섭취량이 저수준(低水準)에서 상(上)으로 증가되었을 때 뇨중칼슘양에 유의적 차이가 있었으나 상(上)에서 고수준(高水準)으로 증가되었을 때는 유의적 차이가 없었다. 이상의 결과에서 뇨중칼슘 배설량은 식이(食餌)칼슘 섭취량의 변화보다 단백질(蛋白質) 섭취량의 변화에 더 영향을 받는 것으로 나타났으며 특히 고단백식(高蛋白食)에 의해서 크게 영향을 받는 것으로 나타났다. 그러므로 상수준(上水準)(117g) 이상의 단백질 과잉섭취는 바람직하지 못하다고 볼 수 있다.