• ALGAE
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• 제38권1호
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• pp.71-80
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• 2023

The oomycete pathogens Pythium porphyrae, causing red rot disease, and Olpidiopsis spp. causing Olpidiopsis-blight, cause serious economic losses to Pyropia sea farms in Korea. During the washing step for Pyropia processing, these pathogens proliferate rapidly, significantly reducing the quality of the final product. To develop non-acidic treatments for these pathogens, various calcium salts were tested against the infectivity of P. porphyrae and Olpidiopsis pyropiae on Pyropia gametophytes, and calcium propionate was the most effective. When Pyropia blades were immersed in 10 mM calcium propionate for 1 h after inoculation with the oomycete pathogen, infection rate of both oomycete pathogens on day 2 was significantly lower (7.1%) than control (>95%). Brief incubation of Pyropia blades in calcium propionate also reduced the spread of infection. The infected area of Pyropia thallus was reduced to 14.3% of the control in 2 days after treatment with 100 mM calcium propionate for 30 s. In field experiments conducted in actual aquaculture farms, it has been shown that a brief 30 s wash every two weeks with 100 mM calcium propionate can effectively reduce the spread of oomycetes throughout the entire culture period. The above results suggest that calcium propionate can be a useful means for controlling the spread of oomycetes not only during laver processing but also during aquaculture.

• The Korean Journal of Physiology and Pharmacology
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• 제70권1호
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• pp.121-133
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• 2019

Dexamethasone inhibits mucin secretion considering the primary option for treating acute asthma exacerbation. However, the mechanism underlying dexamethasone-induced decreased in mucosecretion is unclear. Recent studies have reported that dexamethasone exerts an inhibitory effect on mucosecretion in the lung by modulating the expression of calcium processing genes. However, the expression of the calcium processing genes in the trachea is not examined yet. Thus, the present study is the first to report the localization of calcium processing proteins such as transient receptor potential vanilloid-4 (Trpv4), transient receptor potential vanilloid-6 (Trpv6), calbindin-D_9k (CaBP-9k) and plasma membrane Ca²⁺-ATPase 1 (Pmca1) in the mouse trachea and their glucocorticoid-induced response. In this study, mice were subcutaneously injected with dexamethasone for 5 days, and their tracheal samples were collected by dividing the trachea into the cervical, and thoracic sections based on its anatomical structure. The localization of TRPV4, TRPV6, CaBP-9k, and PMCA1 proteins was detected in the tracheal epithelium, submucosal glands, cartilages and muscles. Dexamethasone treatment downregulated the mRNA expression of the four calcium processing genes and mucin producing genes. The dexamethasone-induced decrease in the secretion of mucosubstances in the trachea was determined by performing Alcian blue-periodic acid-Schiff staining. Thus, the findings of the present study suggest that glucocorticoids simultaneously can regulate the expression of calcium processing genes and tracheal mucosecretion.

• Korean Chemical Engineering Research
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• 제55권4호
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• pp.443-455
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• 2017

This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

• 대한본초학회지
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• 제36권5호
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• pp.15-27
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• 2021

Objectives : The processing of Pinelliae Tuber and Arisaematis Rhizoma is a crucial step to reduce the severe acrid irritation mainly due to the needle-like crystals (raphides). Ginger, alum and bile juice have been used as adjuvant materials for the processing. Methods : Bibliographic research on ancient processing and experimental processing was performed to investigate the toxicity reduction mechanisms of the processing with ginger, alum and bile juice. Results : Ginger has been a major adjuvant for the processing of Pinelliae Tuber, followed by alum and bile juice since Song (宋) and Myeong (明) dynasties, and Arisaematis Rhizoma has been mainly used as Damnamseong (膽南星). The raphides consisting of calcium oxalate, lectin, agglutinin and polysaccharides can induce acrid irritation and the inflammatory reactions. The lipophilic components in the ginger denatured the structure of raphides and 6-gingerol-contained ginger extract attenuated the inflammatory reaction. The calcium ion (Ca²⁺) of calcium oxalate was substituted to the aluminium ion (Al³⁺) of the alum, which damaged the calcium oxalate structure. Lectin attached to the surface of raphides was dissolved in alum solution and consequently its structure was denatured. The cholate in the bile juice formed the complex with the oxalate anion or the calcium cation. Moreover, the enzymes activated by Lactobacillus or Bifidobacterium during the fermentation promoted the fragmentation of oxalate. Conclusion : The adjuvant materials damaged the raphides by denaturing or degrading the calcium oxalate, resulting in the reduction of acrid irritation. Further experimental studies would support the toxicity reduction mechanism of the processing.

• Applied Biological Chemistry
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• 제41권2호
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• pp.147-152
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• 1998

수산가공 부산물을 기능성 식품가공 소재로 이용하기 위한 일련의 연구로 기능성 어류 뼈 칼슘제의 제조 조건(회수방법 및 autoclaving 시간) 및 칼슘제의 특성에 대하여 살펴보았다. 명태 뼈에 물을 가하고 autoclaving한 칼슘제가 기타 방법으로 제조한 칼슘제에 비하여 칼슘함량은 낮았고, 수율 및 칼슘 가용화율은 높았다. 칼슘제 제조를 위한 autoclaving 처리시간은 40분간 처리한 것이 이보다 단시간 처리한 것보다 칼슘의 함량 및 가용화율은 높았고, 수율은 낮았다. 그러나 이보다 장시간 처리한 것과는 이들 성분에서 차이가 없었다. 이상의 결과로 미루어 보아 명태 뼈에 물을 가하고 40분간 autoclaving한 칼슘제가 기타 어종, 방법 및 autoclaving 시간으로 제조한 것보다 우수하다고 판단되었다. 이 조건으로 제조한 칼슘제는 산성조건(pH 2)에서 1시간동안 진탕$(37^{\circ}C)$으로 거의 가용화 되었고, 이를 중성조건(pH 7.0)에서 3시간동안 진탕$(37^{\circ}C)$함으로서 약 59%가 가용화 되었다.

• Fisheries and Aquatic Sciences
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• 제19권7호
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• pp.30.1-30.7
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• 2016

Due to decreased supplies of marine resources and byproducts, new processing technologies for the development of analogs for natural fishery products are becoming increasingly important in the fishing industry. In the present study, we investigated the optimal processing conditions for flying fish roe analogs based on alginate hydrogels. Optimized processing of these analogs was performed by response surface methodology. The optimal processing conditions for the flying fish roe analogs (based on sphericity) were at a sodium alginate concentration of 2.41 %, calcium chloride solution curing time of 40.65 min, calcium chloride concentration of 1.51 %, and a reactor stir speed of $254{\times}g$. When the experiment was performed under these optimized conditions, the size (mm), sphericity (%), and rupture strength (kPa) of the analogs were $2.2{\pm}0.12$, $98.2{\pm}0.2$, and $762{\pm}24.68$, respectively, indicating physical properties similar to their natural counterparts.

• Journal of Nutrition and Health
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• 제28권2호
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• pp.144-151
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• 1995

This study investigates the supplementing effects of milks by various heat treatment on growth performance and protein and calcium metabolism of rats. For 4 weeks, raw, LTLT-HTST-and UHT-processed milks were given to rats which fed on a calcium free, semi-synthetic diet containing 5%casein. There were no significant differences among the experimental groups in weight gain, feed efficiency ratio and the serum level of total protein and calcium. Also, no significant differences were showed in protein efficiency, nitrogen balance, apparent protein digestibiltiy and the contents of weight and calcium of the left femur as well as 2 incisors. However, the biological value of protein in the UHT-milk group was significantly higher than that of the raw-milk group. The apparent calcium digestibility and calcium balance in the UHT-milk group were higher than those in the raw-, LTLT- and HTST-milk groups. The weight of left femur in all the groups supplemented with various heat-treated milks was significantly impair the nutritive value of protein and calcium in milk. Futhermore, UHT-processing may improve the bioavailability of protein and calcium in milk.

• Journal of Ceramic Processing Research
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• 제20권6호
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• pp.655-659
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• 2019

Calcium phosphates such as HA (hydroxyapatite), β-TCP (tricalcium phosphate) and biphasic HA/β-TCP, were synthesized by wet chemical precipitation in aqueous solution combined with ball milling process. Nanosize powders of the calcium phosphates were synthesized using Ca(OH)2 and H3PO4. The effects of initial precursor Ca/P ratio (1.30, 1.50 and 1.67), ball milling process and post heat-treatment on the phase evolution behavior of the powders were investigated. The phase of resulting powder was controllable by adjusting the initial Ca/P ratio. HA was the only phase for as-prepared powders in both cases of Ca/P ratios of 1.50 and 1.67. The single HA phase without any noticeable second phase was obtained for the initial Ca/P ratio of 1.67 in the overall heat-treatment range. Pure β-TCP and biphasic calcium phosphate (HA/β-TCP) were synthesized from precursor solutions having Ca/P molar ratios of 1.30 and 1.50, respectively, after having been heat-treated above 700 ℃. The β-TCP phase has appeared on the pre-existing DCPD (dicalcium phosphate dihydrate) and/or HA phase. Dense ceramics having translucency were obtained at a considerably lower sintering temperature. The modified process offered a fast, convenient and economical route for the synthesis of calcium phosphates.

• 한국수산과학회지
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• 제33권2호
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• pp.158-163
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• 2000

참치 통조림 부산물인 자숙 가다랑어뼈를 칼슘제로 이용하기 위하여 칼슘추출조건 (추출방법 및 시간) 및 그 특성에 대하여 살펴보았다. 다량의 지질이 혼재한 자숙 가다랑어뼈로부터 칼슘제로 제조하기 위한 추출방법으로는 회화처리가 고온가압처리 및 진탕 처리보다 어취가 없으면서 백색을 나타내어 적절하였고, 백색도 및 칼슘 가용화율로 미루어 회화처리 최적조건은 $900{\circ}C, 15분$이었다. 최적조건에서 회화처리한 칼슘제의 응집은 진탕시간이 경과할수록 증가하여 16시간에 $86.1{\%}$로 최고에 달하였고, 용액 pH가 산성조건 (pH 2-5)에서는 거의 일어나지 않았으나, 중성조건 (pH 6-8)에서 급격히 증가하여 최대에 이르렀고, 알칼리조건 (pH 9-11)에서는 중성조건과 거의 차이가 없었다. 이상의 결과로 보아 최적조건에서 처리한 칼슘제의 경우도 중성부근에서는 가용화율이 낮아 기능성 개선제 또는 고차 수산가공품의 탄력 증강 등과 같은 품질개선제로 이용되기 위하여는 용해도 개선을 위한 적절한 처리가 시도되어야 할 것으로 판단되었다.

• 한국세라믹학회지
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• 제53권1호
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• pp.7-12
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• 2016

In this paper, we have developed a simple, new and economical carbonation method to synthesize a pure form of aragonite needles using dolomite raw materials. The obtained aragonite Precipitated Calcium Carbonate (PCC) was characterized by XRD and SEM, for the measurement of morphology, particle size, and aspect ratio (ratio of length to diameter of the particles). The synthesis of aragonite PCC involves two steps. At first, after calcinated dolomite fine powder was dissolved in water for hydration, the hydrated solution was mixed with aqueous solution of magnesium chloride at $80^{\circ}C$, and then $CO_2$ was bubbled into the suspension for 3 h to produce aragonite PCC. Finally, aragonite type precipitated calcium carbonate can be synthesized from natural dolomite via a simple carbonation process, yielding product with average particle size of $30-40{\mu}m$.