• Journal of Plant Biology
• /
• 제39권3호
• /
• pp.173-177
• /
• 1996

A novel calcium binding protein (CaBP) was purified to electrophoretic homogeneity from Dunaliella salina. In the course of purification experiment, this CaBP was identified as a monomer and its molecular weight was about 21 kDand isoelectric point (pI) value was about 4.1 using isoelectrofocusing. This CaBP was able to bind Ca2+ even in the pressence of an excess MgCl2 and KCI both in solution. In the SDS-PAGE, the Ca2+-bound form was slower than the Ca2+-free form in the nondenaturing PAGE. This means that the CaBP undergoes conformational change in the Ca2+-bound condition. Furthermore, UV absorption spectrum and fluorescence intensity of this CaBP was investigated. UV absorption peak was appeared at about 258 nm and decreased somewhat in Ca2+-bound condition. In the measurement of fluorescence, maximum intensity was appeared at 303 nm and decreased in Ca2+-bound state, similarly as UV absorption spectrum. These show distinct changes upon Ca2+-binding, which indicate of structural and/or dynamic changes largely reminiscent of other members of the EF-hand Ca2+-binding protein family.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제2권2호
• /
• pp.126-131
• /
• 1997

The biosorption and desorption of Cr, Cu and Al were carried out using brown marine algae Sargassum fluitans biomass, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by physical and chemical pretreatment. The maximum uptake of Cr, Cu and Al was independent of the alginate content. The maximum uptaker of Al was two times(mole basis) than those of Cu and Cr. The aluminum-alginate complex was found in the sorption solution of raw and protonated biomass. Most of Cu, Al and light metals sorbed in the biomass were eluted at pH 1.1. However, only 5 to 10% of Cr sorbed was eluted at pH 1.1. The stoiceometric ion exchange between Cu and Ca ion was observed on Cu biosorption with Ca-loaded biomass. A part of Cr ion was bound to biomass as Cr(OH)2+ or Cr(OH)2+. Al was also bound to biomass as multi-valence ion and interfered with the desorbed Ca ion. The behavior of raw S. fluitans in ten consecutive sorption-desorption cycles has been investigated in a packed bed flow-through-column during a continuous removal of copper from a 35 mg/L aqueous solution at pH 5. The eluant used was a 1%(w/v) CaCl2/HC solution at pH 3.

• Ocean and Polar Research
• /
• 제32권3호
• /
• pp.177-186
• /
• 2010

A sequential extraction technique was used to study sediment phosphorus speciation and its relative importance in the intertidal flat of Keunso Bay during summer and winter for a better understanding of the phosphorus cycle and bioavailability in intertidal sediments. Loosely sorbed P contents were the lowest among the five P-pools and showed little seasonal or spatial variation. Although Fe-bound P contents were almost constant in winter, they decreased rapidly with sediment depth in summer. The dissolution of Fe oxides, used as an oxidant for the anaerobic respiration, ascribed the rapid decrease of Fe-bound P in summer. Al-bound P contents displayed little seasonal variation, but showed a large spatial variation, with higher values in the upper intertidal flat. Comprising about 50% of total P, Ca-bound P contents were the highest among the five P-pools. Ca-bound P contents were higher in winter than summer, but did not exhibit a clear spatial variation. Organic P contents were higher in summer than winter, which was associated with higher primary production and clam biomass in summer. Organic P contents were higher in the lower intertidal flat than the upper intertidal flat. In Keunso Bay, bioavailable P contents of the intertidal flat comprising about one third of total P ranged from 2.41 to 5.09 ${\mu}molg^{-1}$ in summer and 3.82 to 5.29 ${\mu}molg^{-1}$ in winter. The bioavailability of P contents was higher in the lower intertidal flat than the upper intertidal flat, which was attributed to the large clam production in the lower intertidal flat.

• 한국토양비료학회지
• /
• 제49권4호
• /
• pp.327-334
• /
• 2016

In order to compare phosphorus (P) behavior of livestock manure compost (LMC) and chemical fertilizer (CF) applied to the sea-reclaimed land soils, incubation experiments were conducted for five weeks. Four soils differing textural classes, sandy loam and clay loam, and electric conductivity (EC) value, high and low, were applied with CF and LMC. LMC was applied at the level of 0, 1, 2, and 3% on the soil weight basis and CF was applied at the same levels of P as LMC. The results showed that increase of P application rate of CF and LMC led to linearly increase available $P_2O_5$ and $0.01M\;CaCl_2$ extractable P contents regardless of soil texture and EC. However, 0.01M $CaCl_2$ extractable P from soil applied with CF was significantly higher than with LMC. Correlation analysis between $0.01M-CaCl_2$ extractable P and fractionated P by different extraction methods showed that $0.01M-CaCl_2$ extractable P positively correlated with KCl-P (soluble and exchangeable P) and HCl-P (Ca and Mg bound P). However, NaOH-P (Fe and Al bound P and organic P) and residual P was adverse. The amount of NaOH-P significantly influenced to the amount of 0.01M $CaCl_2$ extractable P of CF and LMC in the soils. The application of LMC at sandy loam soil could be carried out in the consideration of nutrient leaching and crop uptake.

• 약학회지
• /
• 제39권1호
• /
• pp.48-54
• /
• 1995

Coupling of tetracycline(Tc) to dithiocarbamate chitosan(DTCC) via chelate bond was investigated varying reaction time, concentration, temperature, pH, and Ca(II)/Tc ratio. The amount of Tc bound to matrix increased to give a maximum and decreased as the reaction proceeded. The degree and rate of dissociation of Tc complex were affected by the reaction temperature, and pH. By running the reaction at low temperature and pH, the degree of dissociation was greatly diminished. Properties of drug-release from DTCC-Ca(II)-Tc complex were studied by batch- and flow-method and release of Tc and CA(II) by flow method followed nearly zero-order. DTCC-Ca(II)-Tc showed very prolonged antimicrobial activity compared to that of free Tc.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권1호
• /
• pp.1-9
• /
• 2014

Calcium (Ca) and phosphorus (P) are minerals that have important physiological functions in the body. For formulation of diets for pigs, it is necessary to consider an appropriate Ca:P ratio for an adequate absorption and utilization of both minerals. Although both minerals are important, much more research has been conducted on P digestibility than on Ca digestibility. Therefore, this review focuses on aspects that are important for the digestibility of Ca. Only values for apparent total tract digestibility (ATTD) of Ca have been reported in pigs, whereas values for both ATTD and standardized total tract digestibility (STTD) of P in feed ingredients have been reported. To be able to determine STTD values for Ca it is necessary to determine basal endogenous losses of Ca. Although most Ca is absorbed in the small intestine, there are indications that Ca may also be absorbed in the colon under some circumstances, but more research to verify the extent of Ca absorption in different parts of the intestinal tract is needed. Most P in plant ingredients is usually bound to phytate. Therefore, plant ingredients have low digestibility of P due to a lack of phytase secretion by pigs. During the last 2 decades, inclusion of microbial phytase in swine diets has improved P digestibility. However, it has been reported that a high inclusion of Ca reduces the efficacy of microbial phytase. It is possible that formation of insoluble calcium-phytate complexes, or Ca-P complexes, not only may affect the efficacy of phytase, but also the digestibility of P and Ca. Therefore, Ca, P, phytate, and phytase interactions are aspects that need to be considered in Ca digestibility studies.

• 한국식품영양과학회지
• /
• 제39권7호
• /
• pp.1073-1077
• /
• 2010

해조류는 다당류인 수용성 식이섬유와 무기질의 공급원으로 그 필요성이 증대되고 있다. 그러나 인간이나 단위 동물에 있어서는 해조류의 세포벽물질을 분해할 수 있는 효소를 갖고 있지 않은 것으로 알려져 있어 이에 결합된 무기질은 인체 내 소화가 대부분 되지 않는다. 따라서 본 연구는 해조류의 무기질 함량을 측정하고, 해조류 다당류인 세포벽 물질(NDF, netural detergent fiber)에 결합된 다량 무기질인 Ca, P, Mg을 측정하여, 원래 해조류에 함유되어 있던 무기질 함량에서 NDF에 결합된 무기질의 함량을 감한 후 계산하여 실질적인 해조류의 무기질 추정 이용률을 산정하였다. Ca과 Mg의 경우, NDF에 결합된 무기질의 평균 함량은 각각 77.59, 45.62 mg/100 g NDF로 모두 96% 이상의 높은 추정 이용률을 보였고, P의 경우에는 NDF에 결합된 무기질의 함량이 많아 그 추정 이용률은 73.24%로 비교적 낮았다. P의 경우, NDF에 결합된 함량이 비교적 높았지만 70% 이상이 실질적으로 소화되어 이용가능하며, Ca과 Mg은 모두 96% 이상의 높은 추정 이용률을 보여 대부분의 무기질이 실질적으로 소화되어 이용되는 것으로 보인다. 따라서 해조 다당류인 수용성 식이섬유와 무기질의 급원으로 알려진 해조류는 인체 내의 소화율을 고려한다고 하더라도 무기질의 높은 이용률을 보일 것으로 판단되어 무기질의 급원으로 그 이용이 기대된다. 더욱이 해조류는 한국인에게 부족한 영양소로 주목 받는 Ca을 가장 많이 함유하고 있으며 동시에 그 추정 이용률이 90% 이상으로 높아 Ca의 공급원으로써 해조류의 이용을 기대하며, 추후 추정 이용률을 토대로 소화율을 고려한 무기질의 생체이용률에 관한 연구가 활발히 진행되어야 한다고 사료된다.

• 한국환경과학회지
• /
• 제28권5호
• /
• pp.511-520
• /
• 2019

This study was investigated to improve the phosphorus release and water quality by transformation of sedimentary P fraction for application of $CaO_2$. For the experiment, 0.5% (w/w) of $CaO_2$ was homogenized in the sediment and incubated with the control for 20 days. The analytical results showed that pH increased with $CaO_2$ and redox potential (ORP) was improved in the sediment of the reactor. The growth rate of chlorophyll-a was lower in the $CaO_2$ reactor and Dissolved Oxygen (DO) of overlying water maintained higher than that of the control. Total phosphorus (T-P) concentration in the overlying water increased from the initial concentration to 0.304mg/L in the control at 20 days. The reactor of $CaO_2$ was lowered by 29.3%. Ex-P, Fe-P and Ca-P in sediment P fraction were increased with the $CaO_2$. The formation of bound Fe-P and Ca-P in the sediments seemed to control the release of P by removing the Soluble Reactive Phosphorus (SRP) presented in the pore water. From the result, this indicated that the reduction of P release from the sediments seems to be effective in suppressing the eutrophication of P and improving the oxygen condition in the water quality with the application of $CaO_2$.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제27권2호
• /
• pp.76-86
• /
• 2022

Calcium (Ca) and potassium (K) were introduced to remove Sr and Cs in soil, respectively. Four factor and three level Box-Bhenken design was employed to determine the optimal washing condition of Ca- and K-based solutions, and the ranges tested were 0.1 to 1 M of Ca or K, L/S ratio of 5 to 20, washing time of 0.5 to 2 h, and pH of 2 to 7. The optimal washing condition determined was 1 M of Ca or K, L/S ratio of 20, washing time of 1 h, and pH of 2, and Ca-based and K-based solutions showed 68 and 81% removal efficiency for Sr and Cs, respectively in soil. For comparison, widely used conventional washing agents such as 0.075 M EDTA, 0.01 M citric acid, 0.01 M oxalic acid, and 0.05 M phosphoric acid were tested, and they showed 25 to 30% of Sr and Cs removal efficiency. Tessier sequential extraction was employed to identify the changes in chemical forms of Sr and Cs during the washing. In contrast to the conventional washing agents, Ca-based and K-based solutions were able to release relatively strongly bound forms of Sr and Cs such as Fe/Mn-oxide and organic matter bound forms, suggesting the involvement of direct substitution mechanism, probably due to the physicochemical similarities between Sr-Ca and Cs-K.

• 대한수의학회지
• /
• 제33권2호
• /
• pp.337-343
• /
• 1993

To determine the test conditions to enhance the use of hamster test in dogs, semen were collected from four dogs which had been proven to be fertile in the past and then preserved in BWW (Biggers, Whitten, Whittingham) medium for about 20 hours. The semen were given each different treatment according to the experimental design and coincubated with zona-free hamster ova for 5 hours. The ova were stained by lacmoid and examined under phase contrast microscope to investigate the rates of ova bound with sperm(sperm binding) and ova penetrated by sperm (penetration), and also numbers of both bound and penetrated sperm per ovum. In comparison of different concentrations of canine sperm, the rate of sperm binding was higher in $1.5{\times}10^8$, $1{\times}10^8$, and $5{\times}10^7$ sperm concentrations than $5{\times}10^5$ concentration(p<0.01), and also than $5{\times}10^6$ concentration(p<0.05), respectively. The number of bound sperm per ovum was considerably higher in $1.5{\times}10^8$ sperm concentration than $5{\times}10^7$, $1.5{\times}10^6$, and $5{\times}10^5$ concentrations(p<0.01). The rate of penetration was considerably higher in $1.5{\times}10^8$ and $1{\times}10^8$ sperm concentrations than $5{\times}10^5$ concentration,(p<0.01), and also the higher result of penetration was shown in $5{\times}10^7$ than $5{\times}10^5$ (p<0.05). The number of penetrated sperm per ovum was considerably higher in $1.5{\times}10^8$ sperm concentrations than $5{\times}10^5$(p<0.01), and also the higher number was shown in $1{\times}10^8$ than $5{\times}10^5$ (p<0.05). In comparison of the different preincubation period of canine spermatozoa, no difference was obtained in the results of hamster test among the preincubation periods of 4 hours, 18~24 hours and 48 hours. The canine spermatozoa in BWW medium with $Ca^{2+}$(1.3mM) and without FCS(fetal calf serum), with both $Ca^{2+}$(1.3mM) and FCS, with $Ca^{2+}$(2.6mM) and without FCS, and with both $Ca^{2+}$(2.6mM) and FCS showed no difference in the results of hamster test.These results indicated that the appropriate concentration of sperm should be given in hamster test for dog sperm.