• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3544-3550
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• 2012

Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt=$k[BAT][CTZH]^{0.80}[H^+]^{-0.48}$ in acid medium and -d[BAT]/dt=$k[BAT][CTZH]^{0.48}[OH^-]^{0.52}[PTS]^{-0.40}$ in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using $D_2O$. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.317-326
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• 2021

Vanillyl alcohol (VA), which is abundant in Vanilla bean, has strong antioxidant activity. However, the use of VA in the food and cosmetics industries is limited, due to its low solubility in emulsion or organic solvents. Meanwhile, medium chain fatty acids and medium chain monoglycerides have antibacterial activity. We synthesized butyric acid vanillyl ester (BAVE) or caprylic acid vanillyl ester (CAVE) from VA with tributyrin or tricaprylin through transesterification reaction using immobilized lipases. BAVE and CAVE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals in organic solvents. In addition, BAVE and CAVE decreased the production rate of conjugated diene and triene in the menhaden oil-in-water emulsion system. While BAVE showed no antibacterial activity, CAVE showed antibacterial activity against food spoilage bacteria, including Bacillus coagulans. In this study, the antibacterial activity of vanillyl ester with medium chain fatty acid was first revealed. Zeta potential measurements confirmed that BAVE and CAVE were inserted into B. coagulans membrane. In addition, the propidium iodide uptake assay and fluorescent microscopy showed that CAVE increased B. coagulans membrane permeability. Therefore, CAVE is expected to play an important role in the food and cosmetics industries as a bi-functional material with both antioxidant and antibacterial activities.

• 원예과학기술지
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• 제29권5호
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• pp.488-493
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• 2011

Callus culture initiation of strawberry (Fragaria${\times}$ananassa Duch.) was investigated at different Murashige and Skoog (MS) medium strengths, types and concentrations of plant growth regulators, and incorporating a cold pretreatment period to determine the optimal nutritional and environmental conditions. No high quality callus was induced on MS media without auxin regardless of medium strength. When 6-benzylaminopurine (BA) was combined with indole acetic acid (IAA), naphthalene acetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D), high quality callus were highly induced compared to medium supplemented with auxin alone. When $0.5mg{\cdot}L^{-1}$ BA was combined with IAA, NAA, and 2,4-D, high quality callus induction was more effective than the medium supplemented with the other BA concentrations. The best combination of auxin and cytokinin for high quality callus induction was $1.0mg{\cdot}L^{-1}$ NAA and $0.5mg{\cdot}L^{-1}$ BA. Although the differences in callus induction were not significant, high quality callus induction at half strength MS medium was more effective than at full strength medium. When $30g{\cdot}L^{-1}$ sucrose was added to the half strength MS medium, the rate of high quality callus induction increased. The optimum cold pretreatment temperature and period for high quality callus induction were $4^{\circ}C$ and 72 h, respectively. Regeneration rate of high quality callus increased in MS medium supplemented with thidiazuron.

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.435-442
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• 2001

Poly(3-hydroxy-5-phenylvalerate) [P(3HPV)] was efficiently accumulated from 5-phenylvalerate (5PV) in Pseudomonas putida BM01 in a mineral salts medium containing butyric acid (BA) as the cosubstrate. A nove aromatic copolyester, poly(5 mol% 3-hydroxy-4-phenylbutyrate-co- 95 mol% 3-hydroxy-6-phenylhexanoate) [P(3HPB-co-3HPC)] was also synthesized from 6-phenylhexanoate (6PC) plus Ba. The two aromatic polymers, P(3HPV) and P(3HPB-co-3HPC), were found to be amorphous and showed different glass-transition temperatures at $15^{\circ}C$ and $10^{\circ}C$, respectively. When the bacterium was grown ina medium containing 20 mM 5PV as the sole carbon source for 140 h, 0.4 g/l of dry cells was obtained in a flask cultivation and 20 wt% of P(3HPV) homopolymer was accumulated in the cells. However, when it was grown with a mixture of 2 mM 5PV and 50 mM BA for 40 h, the yield of dry biomass was increased up to 2.5 g/l and the content of P(3HPV) in the dry cells was optimally 56 wt%. This efficient production of P(3HPV) homopolymer from the mixed substrate was feasible because BA only supported cell growth and did not induce any aliphatic PHA accumulation. The metabolites released into the PHA synthesis medium were analyzed using GC or GC/MS. Two $\beta$-oxidation derivatives, 3-phenylpropionic acid and trans-cinnamic acid, were found in the 5V-grown cell medium and these comprised 55-88 mol% of the 5PV consumed. In the 6PC-grown medium containing Ba, seven ${\beta}$-oxidation and related intermediates were found, which included phenylacetic acid, 4-phenylbutyric acid, cis-4-phenyl-2-butenoic acid, trans-4-phenyl-3-butenoic acid, trans-4-phenyl-2-butenoic acid, 3-hydroxy-4-phenylbutyric acid, and 3-hydroxy-6-phenylhexanoic acid. Accordingly, based on the metabolite analysis, PHA synthesis pathways from the two aromatic carbon sources are suggested.

• 약학회지
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• 제16권1호
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• pp.47-54
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• 1972

O,O-Dimethyl-S-(phthalimido)methylphosphorodithioate (PMP) is changed into phosphine, phosphate, and phosphorothioate, when it is treated with metallic zinc in acidic medium after alkaline hydrolysis. The amount of phosphine evolved is about five times as much in sulfuric acid medium as it is in hydrochloric acid. When one micro mole of hydrolyzed PMP is treated with 8 grams of metallic zinc and 30 ml of 10 N-sulfuric acid, it is changed into 0.42 micro moles of phosphine, 0.14 micro moles of phosphorothioate, and 0.44 micro moles of phosphate.

• Journal of Microbiology and Biotechnology
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• 제10권1호
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• pp.51-55
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• 2000

Surface culture fermentation using Aspergillus niger was studied for gluconic and citric acid production at different C/N ratios. A culture of A. niger was found to produce either gluconic acid alone, a mixture of gluconic and citric acid, or citric acid alone depending on the level of nitrogen in the medium (4 to 18mM). Glucose oxidase from the mycelial mat was also analyzed at different levels of nitrogen in the media. By choosing the level of nitrogen in the medium at the start of fermentation, it is possible to produce either of the two acids as the dominant product or the two together as a mixture.

• 한국수산과학회지
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• 제28권6호
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• pp.812-813
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• 1995

Lactococcal cells are nutritionally fastidious and thus, generally cultured either in milk or M17 medium (Terzaghi and Sandine, 1975). In this study, Lactococcus cremoris wild-type (KH) and its less­proteolytic mutant (KHA1) cells were grown on the M17 medium or with modified M17 medium by replicated parallel experiments. The modified M17 medium had the same composition as M17 medium, except that lactose was replaced by glucose. Analyses of culture-broth samples, in which the M17 and the modified M17 media were used, were conducted by high-performance liquid chromatography (HPLC). But, working with these media created noisy problems in analyses of samples. Therefore, a new semi-synthetic medium was developed on the basis of nutritional requirements (Morishita et al., 1981). The composition of the semi-synthetic medium determined on the basis of the nutritional requirements and the composition of milk, is presented in Table 1. The composition of M17 medium is also presented and compared in the table. L. cremoris KH and KHA1 cells were grown again on the new synthetic medium containing glucose or lactose. The broth samples were then drawn and analyzed by HPLC. Clearer separations of fermented products were achieved from the new medium than those with the M17 and the modified M17 media. In comparison with the M17 or the modified M17 media, growth on the new medium was good (Kim et al, 1993). Additional fermentations were also carried out at a controlled pH of 7.0, where enhanced growth of lactococcal cells was obtained. In the fermentations, samples were also analyzed for the concentrations of sugar and lactic acid. The results showed that the new synthetic medium was as good as or better than the M 17 and the modified M 17 media. This is because casein hydrolysate in the synthetic medium provided a ready supply of amino acids and peptides for L. cremoris KH and KHA1 cells. Lactic acid bacteria (LAB) including Lactococcal cells have been known to be an effective means of preserving foods, at the same time as giving particular tastes in fields of dairy products. LAB also have always occupied an important place in the technology of sea products, and marine LAB have known to be present in traditional fermented products (Ohhira et al, 1988). To apply the new synthetic medium to marine LAB, two different LAB were isolated from pickled anchovy and pollacks caviar and were grown on the new media in which various concentrations of NaCl $(3, 5, 7 and 10\%)$ added. They were also grown on the medium solution in natural seawater $(35\%o\;salinity)$ and on the solution of natural seawater itself, too. As seen in Fig. 1, Marine LAB were grown best on the synthetic medium solution in natural seawater and the higher concentrations of NaCl were added to the medium, the longer lag-phase of growth profile appeared. Marine LAB in natural seawater were not grown well. From these results, the synthetic medium seems good to cultivate cells which are essential to get salted fish aged. In this study, it showed that the new synthetic medium provided adequate nutrition for L. cremoris KH and KHA1 cells, which have been used as cheese starters (Stadhouders et al, 1988). Using this new medium, the acid production capability of starter cultures could be also measured quantitatively. Thus, this new medium was inferior to the M17 or the modified M17 medium in culturing the cheese starters and in measuring fermentation characteristics of the starter cells. Moreover, this new medium found to be good for selected and well-identified marine LAB which are used in rapid fermentations of low-salted fish.

• 한국식품영양과학회지
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• 제25권4호
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• pp.695-700
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• 1996

매실즙을 이용한 식초생산을 위하여 초산생성능이 우수한 초산균을 재래초로 부터 분리, 동정하고 매실 초 제조를 위한 최적 발효조건을 검토하였다. 재래초로부터 분리한 16균주 중 매실즙배지에서 가장 초산 생성능이 우수한 균주로 선정된 균주는 Acetobuter sp. VC-2로 동정 되었다. 이 균주의 증식 최적 조건을 살펴본 결과, 최적 온도는 3$0^{\circ}C$였으며 정치배양 보다는 진탕배양이 효과적으로 나타났다. 초산생성에 적합한 배지의 조성은 매실즙 30%, 초기 산도 2%, 에탄을 농도 6%, 포도당 0.2%, yeast extract 0.3%가 함유된 배지였다. 이와 같은 배양조건에서 매실식초는 8일째에 발효가 거의 완료되었으며, 이때 얻은 매실초의 총 산도는 6.5%였다. 주요 유기산으로는 acetic acid, citric acid, malic acid 및 tartaric acid였는데, 이들 함량은 4.28, 1.38, 0.48 및 0.30%로 각각 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제41권4호
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• pp.287-292
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• 2013

진한 산 가수분해 반응 중 2차 가수분해 조건에서 포도당과 자일로스의 반응을 수소 핵자기 공명 분광분석을 통하여 정량적으로 분석하였다. 정량분석은 아노머성 수소, 퓨란과 개미산의 특징적인 피크를 이용하여 실시하였다. 진한 산 가수분해의 2차 가수분해 조건에서 포도당의 일부가 5-hydroxymethylfufural (5-HMF) 중간 구조를 거쳐 levulinic acid와 개미산으로 분해되었음을 확인하였다. 자일로스는 furfural 중간 구조를 거쳐 개미산으로 분해가 되었으며, 포도당은 자일로스보다 2차 가수분해 조건에서 산에 의한 퓨란계 화합물의 전이가 느리게 전환되어 단당의 안정성이 높았다. 퓨란계 화합물로 전환된 이후, 산에 민감한 5-HMF는 쉽게 formic acid와 levulinic acid로 전환되었지만, furfural은 formic acid로의 분해 반응이 더디게 진행되어 furfural의 농도가 5-HMF보다 상대적으로 높게 나타났다.

• 한국응용과학기술학회지
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• 제3권1호
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• pp.49-55
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• 1986

The purpose of the study was to find an effect of Medium Chain Triglycerids (MCT) diet on cholesterol metabolism in rat. Sprague-Dawley rats were fed two different diets containing MCT(trioctanoate) and corn oil respectively. After feeding to each group for four weeks, the levels of serum and liver cholesterol, the excretion rates of fecal and biliary steroids, and also bile acid composition were investigated. The results obtained from the study are as follows : (1) The average body weight gain in MCT group was almost same as that in the corn oil group. (2) The concentration of serum cholesterol in MCT group was lower than that in the corn oil group. Therefore it is confirmed that the cholesterol lowing action of MCT diet was practically high. (3) The concentrations of liver cholesterol and Triglyceride in MCT group were almost same as that in the corn oil group. Therefore it is thought that the level of liver lipids was not influenced by the difference of diet in this study. (4) The excretion rate of fecal neutral steroid in MCT group was significantly lower than that in the corn oil group, while the rate of fecal bile acid excretion was about same in both MCT and corn oil group. (5) The composition rates of fecal bile acid such as cholic acid, chenodeoxycholic acid and deoxycholic acid, a secondary acid of cholic acid, in MCT group were significantly lower than that in the corn oil group. (6) The excretion rates of biliary cholesterol and bile acid in MCT group were significantly higher than that in the corn oil group, while the composition rates of biliary bile acid such as chenoddeoxycholic acid and deoxycholic acid in MCT group were significantly higher than that in the corn oil group.