• Food Science and Preservation
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• v.18 no.6
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• pp.884-890
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• 2011

In this study, the quality characteristics of eight kinds of non-sterilized commercial makgeolli were investigated. The alcohol contents of five kinds of makgeolli were determined to be as follows: 5.7~5.8%, G $6.7{\pm}0.1%$, D $6.8{\pm}0.2%$, and C $7.5{\pm}0.1%$. As for the titratable acidity, makgeolli C and D showed higher than 0.5%, H showed $0.49{\pm}0.02%$, and the rest showed 0.45% or less. For the pH levels, there were no significant differences among the samples. The reducing-sugar content was approximately 200 mg%, and those of makgeolli A and F were lower by approximately 90 mg%. As for the organic acids, malic acid was detected only in makgeolli A and G while the acetic-acid content was high in makgeolli C and D. Concerning free sugars, fructose and sucrose were not detected, and the glucose content of makgeolli G was shown to be the highest ($335.1{\pm}40.3$ mg%). The maltose contents were similar ($23.5{\pm}1.0{\sim}45.0{\pm}1.1$ mg%), except for makgeolli G, whose maltose content was $73.5{\pm}1.8$ mg%. For the alcoholic ingredients, 0.4~0.5 mg/mL 1-propanol, 2-methyl-1-propanol, and iso-amylalcohol were detected, a suitable table wine standard. Further studies involving the quality analysis of the leavening agents, fermentation conditions, and fermentation types are needed.

• Korean Journal of Food Science and Technology
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• v.51 no.2
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• pp.97-102
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• 2019

Wheat germ, which is rich in nutrients and phytochemicals, is a by-product during the milling process of wheat kernel. In this study, we aimed to increase the amount of bioactive 2,6-dimethoxy-1,4-benzoquinone (2,6-DMBQ) in wheat germ using the cell-wall-degrading enzyme cellulase (Celluclast 1.5L). The amounts of organic acids, free sugars, and 2,6-DMBQ in wheat germ treated with Celluclast 1.5L were evaluated at various reaction times and temperatures. The results of reversed-phase high-performance liquid chromatography of Celluclast 1.5L-treated wheat germ revealed 2,6-DMBQ, four organic acids (tartaric, acetic, lactic, and succinic acids), and three free sugars (sucrose, fructose, and glucose). As reaction time and temperature of the mixture of wheat germ and Celluclast 1.5L increased, the contents of four organic acids, glucose, fructose, and 2,6-DMBQ increased, but that of sucrose decreased. Taken together, these results suggest that Celluclast 1.5L-treated wheat germ containing increased amounts of 2,6-DMBQ serves as a source of functional ingredients in food industry.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.863-868
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• 2004

Lectin activities and chemical characteristics of Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. originating from the porcine cecal mucosal layer were studied based on hemagglutination assay (HA) and hemagglutination inhibition assay (HIA). Although all the bacterial strains were able to agglutinate erythrocytes of porcine or rabbit origin, much higher HA titers were consistently observed for Lactobacillus spp. than for E. coli or for Bifidobacterium spp. A remarkable reduction in HA titers occurred by the treatment of E. coli and Lactobacillus spp. with protease or trypsin and of Bifidobacterium spp. with protease, trypsin or periodate. There were no significant effects on the HA titers of the three groups of bacteria after the treatment with lipase. Hemagglutination of E. coli was strongly inhibited by D (+)-mannose and D (+)-galactose; Lactobacillus spp. by $\alpha$-L-rhamnose and methyl-$\beta$-galactopyranoside; Bifidobacterium spp. by D (+)-alactose, $\alpha$-L-rhamnose, $\alpha$-L-fucose, L (+)-arabinose, D (+)-mannose, D (-)-fructose at a relatively low concentration (1.43 to 3.75 mg/ml). These results, combined with the enhanced HA activities of the three bacterial strains by modification of rabbit erythrocytes with neuraminidase and abolished HA activity of E. coli after treatment with $\beta$-galactosidase, indicate that it might be the glycoproteinous substances surrounding the surface of the bacterial cells that are responsible for the adhesions of these microorganisms by recognizing the specific receptors on the red blood cell.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.597-599
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• 2000

This study was performed to find out the cryoprotectants for cryopreservation of trochophores and early D-shaped larvae of surf clam, Spisula sachalinensis. Dimethyl sulfoxide (DMSO), ethylene glycol, 1,2-propanediol and methanol were used as cryoprotectant Each cryoprotectant was made to 1.0 M, 2.0 M, 3.0 M with dilution of 0.2 M fructose and 0.2 M sucrose. The trochophoers and early D-shaped larvae were immersed in each preparation for 10 minutes to reach equilibration and cryopreserved in liquid nitrogen. Survival rates of post-thawed trochophores and early D-shaped larvae in 2.0 M DMSO with 0.2 M sucrose were the highest as $91.4{\%}\;and\;78.9{\%}$, respectively.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.914-920
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• 2011

Vibrio cholerae utilizes mannitol through an operon of the phosphoenolpyruvate-dependent phosphotransferase (PTS) type. A gene, mtlD, encoding mannitol-1-phosphate dehydrogenase was identified within the 3.9 kb mannitol operon of V. cholerae. The mtlD gene was cloned from V. cholerae O395, and the recombinant enzyme was functionally expressed in E. coli as a $6{\times}$His-tagged protein and purified to homogeneity. The recombinant protein is a monomer with a molecular mass of 42.35 kDa. The purified recombinant MtlD reduced fructose 6-phosphate (F6P) using NADH as a cofactor with a $K_m$ of $1.54{\pm}0.1$ mM and $V_{max}$ of $320.8{\pm}7.81\;{\mu}mol$/min/mg protein. The pH and temperature optima for F6P reduction were determined to be 7.5 and $37^{\circ}C$, respectively. Using quantitative real-time PCR analysis, mtlD was found to be constitutively expressed in V. cholerae, but the expression was up-regulated when grown in the presence of mannitol. The MtlD expression levels were not significantly different between V. cholerae O1 and non-O1 strains.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.647-650
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• 2006

D-Psicose 3-epimerase (DPE) catalyzes the interconversion of D-fructose to D-psicose by epimerizing the carbon-3 position. The DPE from Agrobacterium tumefaciens was cloned and expressed in Escherichia coli. The expressed enzyme was purified by affinity chromatography on an IMAC, gel filtration chromatography on a Sephacryl S-300 HR, and anion-exchange chromatography on a RESOURCE Q. The molecular mass of the purified enzyme was estimated to be about 135 kDa by Superdex 200 gel filtration chromatography, corresponding to a homotetramer. The enzyme produced crystals suitable for X-ray diffraction to a $2.0{\AA}$ resolution at 100 K. The crystals were found to belong to the orthorhombic space group $P2_12_12_1$, with unit-cell parameters a=102.4, b=113.0, and $c=131.8{\AA}$. In addition, the calculated packing parameter $(V_m)$ was $2.79{\AA}^3/Da$, the solvent content was 55.92%, and an asymmetric unit consisted of four monomers.

• Korean Journal of Medicinal Crop Science
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• v.28 no.6
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• pp.455-462
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• 2020

Background: The purpose of this study was to analyze the applicability of dried jujube (Zizypui Fructus) distributed by size as a functional food material and herbal medicine by evaluating its physicochemical characteristics and betulinic acid content. Methods and Results: It was shown that the carbohydrate content of in jujube fruit significantly increased with fruit size; 81.42% for large, 79.83% for medium, and 76.39% for small. Similarly, the dilute ethanol extract content of each group was 72.48% (large), 69.56% (medium), and 64.16% (small). A free sugar analysis indicated that glucose, fructose and sucrose were found in quantitieds proportional to jujube fruit size, the total free sugar values were 68.85%, 63.93%, and 57.37% for large, medium, and small fruit sizes respectively. The betulinic acid content for large, medium, and small fruit was 0.50 mg/g, 0.54 mg/g, and 0.58 mg/g respectively, indicating that smaller jujube contained a higher amount of betulinic acid. Conclusions: It is considered that betulinic acid content could be used as a criteria for jujube fruit quality control.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.575-576
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• 2005

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.171-171
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• 2005

• The Korean Journal of Food And Nutrition
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• v.2 no.1
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• pp.1-11
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• 1989

Glucose isomerase (E.C.5.3.1.5) which reversibly catalyzes reaction between D-glucose and D-fructose was demonstrated in cell free extracts of alkalophilic Streptomyces sp. B-2 isolated from soil The optimum temperature, pH, and pH stability were 6$0^{\circ}C$, 10.5, and 7.8, respectively. The production of Gl in xylose and yeast extract was higher than that of other carbon source and nitrogen source. The Gl production was affected by Co2+ and Mg2).