• Journal of Microbiology and Biotechnology
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• v.31 no.11
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• pp.1533-1544
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• 2021

n-Caproic acid (CA) is gaining increased attention due to its high value as a chemical feedstock. Ruminococcaceae bacterium strain CPB6 is an anaerobic mesophilic bacterium that is highly prolific in its ability to perform chain elongation of lactate to CA. However, little is known about the genome-wide transcriptional analysis of strain CPB6 for CA production triggered by the supplementation of exogenous lactate. In this study, cultivation of strain CPB6 was carried out in the absence and presence of lactate. Transcriptional profiles were analyzed using RNA-seq, and differentially expressed genes (DEGs) between the lactate-supplemented cells and control cells without lactate were analyzed. The results showed that lactate supplementation led to earlier CA p,roduction, and higher final CA titer and productivity. 295 genes were substrate and/or growth dependent, and these genes cover crucial functional categories. Specifically, 5 genes responsible for the reverse β-oxidation pathway, 11 genes encoding ATP-binding cassette (ABC) transporters, 6 genes encoding substrate-binding protein (SBP), and 4 genes encoding phosphotransferase system (PTS) transporters were strikingly upregulated in response to the addition of lactate. These genes would be candidates for future studies aiming at understanding the regulatory mechanism of lactate conversion into CA, as well as for the improvement of CA production in strain CPB6. The findings presented herein reveal unique insights into the biomolecular effect of lactate on CA production at the transcriptional level.

• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.102-107
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• 1988

Production of calcium lactate very useful for medical supplies of Ca-therapy was obtained by lactic acid fermentation of lactobacillus sporogenes, a spore forming lactic acid bacterium. Corn steep liquor 1%, soybean enzyme hydrolysate 3%, yeast extract powder 2% can substitute for yeast extract and peptone as nutrient sort traces in fermentation medium using 10% glucose concentration. In the calcium lactate production medium containing yeast extract powder 2%, glucose 18%, CaCO3 12%, the lactic acid fermentation was carried out at 45$^{\circ}C$ for 4days with continuous agitation of 100 rpm. As results, fermentation yield was 97.5%. The five steps such as protein coagulation, decolorizing evaporating, crystallizing, and drying were carried out to harvest calcium lactate from 10l of supernatant of fermented medium to be removed cell and CaCO3. As results, 2065.0g of white crystal calcium lactate dihyrate was recovered and a yield of 84.9% was obtained.

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.45-52
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• 2004

Effects of dietary calcium lactate (CaL-A) and Chungkukjang (Korean native fermented soybean) on bone mass, calcium status, body weight, serum glucose and cholesterol levels in young male rats were investigated. Chungkukjang was fermented by mixing 4 types of Bacillus sp., and then dried at 45$^{\circ}C$. Calcium lactate was prepared from the ash of black snail. The rats were fed a commercial rat diet for 1 week and then the experimental diets for 4 weeks. Animals were divided into four dietary groups: one calcium-deficient diet (Ca-De) and one of three with calcium supplemented diets (5 g calcium/kg diet) with either calcium phosphate (Ca-P), CaL-A, or CaL-A + Chuntkukjang (CaL-AC). Calcium supplemented diets contained 39 g Ca-P/kg diet and 28 g/kg of calcium lactate in the CaL-A and CaL-AC diets. Body weight gains during the 4 weeks in the Ca-P, CaL-A, CaL-AC and Ca-De groups were 130.45 g,112.50 g, 143.40 g and 10.20 g, respectively. Feed consumption of the groups from high to low was CaL-AC > Ca-P > CaL-A > Ca-De. The Ca-De group had low femur weights and low serum calcium concentrations, while they were comparatively high in CaL-AC, Ca-P and CaL-A groups. The Ca-De groups excreted less calcium in urine than did the other rats, probably due to increased absorption of the mineral in Ca-P, CaL-A and CaL-AC groups. Microscopic observations revealed that there were many regularly spaced holes in the femur of Ca-De group, while there were much smaller regularly spaced holes in Ca-P group. However, no holes in femur were observed in the CaL-A and CaL-AC groups. Bone surfaces were especially smooth and clean in the CaL-AC group. Serum concentrations of glucose and total cholesterol were remarkably lower in the CaL-AC group than in the other supplemented groups. These results suggest that calcium from CaL-A has higher bioavailability than from Ca-P, and dietary Chungkukjang may have a beneficial effect on calcium metabolism.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.5
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• pp.598-605
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• 2005

Effects of chitosan-ascorbate(CA) and calcium lactate(CL) on fermentation and quality of squid sikhae were investigated CA and LA were added at $0.5\%$ (designated CA1 and CL1) and $1.0\%$(CA2 and CL2) concentrations, respectively and fermented for 12 days at $10^{\circ}C$. pH of CA-added sikhae was higher than that of control, while acidity of the former was lower than that of the latter. During 12 days of fermentation, CA-added sikhae showed higher protease activity than control by $2.3\~2.6$ times and CL-added sikhae by $2.8\~3.6$ times. At 12 days of fermentation, CA-added sikhae revealed higher protease activity than control by $1.2\~1.4$ times and CL-added sikhae by $1.5\~1.9$ times. CA-added sikhae also showed higher amino-nitrogen content than control by $1.4\~1.7$ times and CL-added sikhae by $1.9\~3.5$ times. In comparison of CA1 with CA2, CA2 showed all higher pH, protease and amylase activity, and amino-nitrogen content than CA1. In analysis of electrophoresis, molecular weights of major proteins in ~w squid were $116.9\~119.0$, 96.5 and 59.3kDa. However, after fermentation for 12 days, a protein band of 119.0kDa disappeared but a new protein band with below 14 kDa appeared in sikhae, especially CA-added sikhae. In sensory evaluation, the intensity of sour taste was the highest for control and the lowest for CA2. Softness of squid was the highest for control and the lowest for CA2. Overall acceptability was the best for CA2. In conclusion, these results suggest use of $1\%$ CA in sikhae preparation as addition of CA(CA2) increased the protease and amylase activity, nitrogen content of amino form, sensory acceptability as well as shelf-life of sikhae.

• Journal of Nutrition and Health
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• v.27 no.2
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• pp.162-171
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• 1994

The purpose of this study was to describe the effects of caffeine ingestion on the metabolic responses during submaximal exercise. Ten male of rowing player aged 18-22yrs. participated in the study. No subjects had any remarkable medical history and none were taking medications. According to the administration of dehydrated caffeine(CA) (6mg/kg) or placebo(PA), they were classified into two groups such as caffeine group and placebo group. A randomized, double-blind, crossover protocol was employed using either CA or PA. Subjects underwent a submaximal bicycle ergometer. Blood was drawn intravenously prior to 60 min., at rest, at 30, and 45 min. of exercise, and recovery period. Plasma concentrations of glucose, free fatty acid and lactate were obtained using enzymatic method. Followings were obtained by the tests and analyses; 1) Blood glucose(BG) of 45 minute of exercise was significantly decreased in CA group of 76.3$\pm$14.8 mg/100ml compared with PA group of 94.9$\pm$11.2 mg/100mg(p<0.5). 2) Free fatty acid(FFA) of 30minute of exercise was significantly increased in CA group of 720$\pm$80 $\mu$Eq/1 compared with PA group of 360$\pm$120 $\mu$Eq/1(p<0.5). After exercise, FFA was significantly higher in CA group than those in PA group(p<0.1). 3) Blood lactate(BL) was not significantly different between the two. After exercise, BL was significantly different in 30 minute(p<05).

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.136-136
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• 2003

Calcium lactate has been known extending shelf-life of several lactic acid fermented foods through buffer action with lactic acid and binding of calcium and pectic polysaccharides in the tissue. But, the effects in kimchi during storage and distribution has not been observed. Calcium lactate is tasteless, nontoxic compounds commonly used in a number of food products. Recent observations have indicated the potential usefulness of calcium lactate as food additive which has anticariogenic-, antimicrobial-, anticalculus, anti- carcinogenic effects and enhancement of bone mineral density. In this work we determined the effects of calcium lactate(CaL)-treatment(0, 1, 2 and 3% against salted Chinese cabbage) on the pH, acidity, microbial counts, content of alcohol insoluble substance and calcium texture, color, scanning electron microscopic observation of kimchi tissue and sensory test during storage. pH of CaL treated kimchi were higher(3.78∼3.92) than that of control products(3.58). Total microbe(TM) of CaL treated kimchis were lower but ratio of lactic acid bacteria against TM was higher than those of control products, respectively. Calcium content of treated products were 3-5 times higher than control products. The hardness and crispy taste of treated products were remarkably higher than those of control products evaluated by SEM observation AIS analysis, sensory and textural analysis. Moreover, evaluation on the pH, acidity and sensory test showed the shelf-life of treated kimchi(CaL 2%) to be 25-30 days, which was 13-15 days longer than that of control products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.241-245
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• 2002

To effectively utilize ostrich egg shell as a calcium source, various conditions for preparation of calcium lactate from ashing powder (ashed for 15 min at 90$0^{\circ}C$) were evaluated. Optimal conditions involved treatment of ashing powder with 30 mL lactic acid solution at room temperature for 15 min with a CaO : lactic acid ratio (mol/mol) of 1:2. Calcium lactate contained 39.70% calcium comparable to that (40.98%) in ostrich egg shell. Solubility of calcium lactate, 97.7%, was considerably higher than those (0.58% and 3.43%, respectively) of ostrich egg shell and ashing powder, indicating that the former can be utilized more effectively as a calcium source than the two latter.

• KSBB Journal
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• v.26 no.1
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• pp.13-18
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• 2011

In this study, precipitation process was developed for the recovery of the lactic acid from calcium lactate fermentation broth. Calcium lactate yield was improved by decreasing the solubility of calcium lactate through the addition of ethanol (25%, v/v) as a co-precipitant. The optimal lime type, lime concentration, stirrer speed, precipitation time, temperature, and solvent amount for $Ca(LA)_2$ precipitation were CaO, 0.0175 g/mL, 220 rpm, 24 h, $5^{\circ}C$, ethanol 25% (v/v), respectively. Lactic acid was easily and efficiently recovered from precipitated $Ca(LA)_2$ by adding sulfuric acid ($Ca(LA)_2/H_2SO_4$ molar ratio=1:1). In the model solution of organic acids and fermentation broth, the overall yields of recovered lactic acid were 62% and 55%, respectively, under the aforementioned optimal conditions.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.43-50
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• 2001

The effects of cardiac ischemia-reperfusion and $\beta$-adrenergic stimulation on metabolic function and energetics were investigated in Lan gendorff-perfused spontaneously hypertensive rat (SHR) hearts. Sarcoplasmic reticulum {TEX}$Ca^{2+}${/TEX}-dependent ATPase and cardiac lactate dehydrogenase (LDH) are additionally studied. The perfusion medium (1.0 mM {TEX}$Ca^{2+}${/TEX}) contained 5 mM glucose(+5 U/L insulin) and 2 mM pyruvate as substrates. Global ischemia was induced by reducing perfusion pressure of 100 to 40 cm {TEX}$H_{2}${/TEX}O, followed by 20 min reperfusin. Isoproterenol (ISO, 1$\mu$M) was infused for 10 min. Coronary vascular resistance and myocardial oxygen consumption ({TEX}$MVO_{2}${/TEX}) of SHR were increased in parallel with enhanced venous lactate during ischemia and reperfusion compared to those of Sprague Dawley (SD) hearts. Although ischemia-induced increase in venous lactate and combined adenosine plus inosine was abolished, coronary vasodilation produced in SD during reperfusion. In SHR, depressed reactive hyperemia was associated with a fall in cardiac ATP and CrP/Pi ratio and a rise in intracellular lactate/Pyruvate ratio. On the other hand, ISO produced coronary functional hyperemia and an increase in {TEX}$MVO_{2}${/TEX}. However, these responses were less than those in SHR hearts. The ATPase activity of SHR was attenuated in free {TEX}$Ca^{2+}${/TEX} concentrations used under basal condition and with ISO compared to that of SD. Venous lactate output and cardiac LDH activity were augmented in SHR as influenced by ISO. These results demonstrate that coronary reactive and functional hyperemia was dpressed in SHR, which cold be explained by alterations in the cytosolic phosphorylation potential and the cytosolic redox state manipulated by LDH, and by abnormal free calcium handling.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.2
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• pp.136-144
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• 2003

This study was conducted to investigate the effect of 0.5% calcium lactate(CaL) on the fermentation of dough and quality and shelf-life of bread. Calcium lactates(CaL-A and CaL-P) were prepared from ash of black snail which contained shell and tissue together(ABS) and powder of the snail(PSB). pH of dough with the CaLs were higher than that of the control md, volume of the dough, loaf volume of bread were lower than those of the control products. But the volumes were almost the same when the pH of the dough were adjusted to pH 5.5. Mean calcium contents of treated bread (39.36~49.70 mg/100 g) were higher than that of control products(13.43 mg/100 g). There was no difference in Hunter $L^{*}$, $a^{*}$, $b^{*}$ values between the control and the treated group. Hardness and gumminess of CaL-A treated bread were the highest, but springiness and cohesiveness were the lowest. All the attributes showed no difference in case of pH adjustment(pH 5.5). The smaller pore and larger air cell with rough surface were observed in the CaL treated bread by SEM analysis. Sensory scores of CaL treated bread showed relatively lower values than those of the control products, but the scores increased by pH adjustment. The shelf-life of bread with CaL-P and CaL-A at 2$0^{\circ}C$ were 4 and 3 days, respectively, while that of the control group 1 day.day.y.