• Food Science and Biotechnology
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• v.17 no.1
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• pp.208-211
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• 2008

Previously, it has been reported that Aspergillus oryzae can efficiently degrade unpleasant odor components such as butyric acid and 3-methyl butanoic acid from meju, a major ingredient in both Korean soybean paste (doenjang) and soy sauce. In this study, the optimal manufacturing conditions for the production of superior quality Korean soybean paste and soy sauce were determined. Specifically, A. oryzae AJ 100 was utilized to improve the flavor of these products. Mixtures of Korean soybean paste and A. oryzae AJ 100 culture (2 : 1), and of Korean soy sauce and A. oryzae AJ 100 culture (5 : 1), were incubated for 2 weeks at $30^{\circ}C$, and showed improved flavor. Butyric acid and 3-methyl butanoic acid were clearly degraded under these culture conditions.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.184-193
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• 2013

Co-signaling molecules are surface glycoproteins that positively or negatively regulate the T cell response to antigen. Co-signaling ligands and receptors crosstalk between the surfaces of antigen-presenting cells (APCs) and T cells, and modulate the ultimate magnitude and quality of T cell receptor (TCR) signaling. In the past 10 years, the field of co-signaling research has been advanced by the understanding of underlying mechanisms of the immune modulation led by newly identified co-signaling molecules and the successful preclinical and clinical trials targeting co-inhibitory molecules called immune checkpoints in the treatment of autoimmune diseases and cancers. In this review, we briefly describe the characteristics of well-known B7 co-signaling family members regarding the expression, functions and therapeutic implications and to introduce newly identified B7 members such as B7-H5, B7-H6, and B7-H7.

• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.159-165
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• 1976

Freshly fermented green beer samples were chillproofed with reduced amounts of papain in order to avoid the deterioration of foam quality. Without being pasteurized, the bottled beer samples were stored at different temperatures for various day and then their foam stabilities were determined. A significant improvement in foam stability was observed in the beer chillproofed with 15 ppm of papain for 22 days at $0^{\circ}C$ and not pasteurized. The findings may be applied in the finishing processes for draft beer where pasteurization is not needed.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.124-128
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• 1998

The procedures currently used for determining microbiological quality of natural mineral water recommend filtration through membrane filters. In this study, we evaluated the effect of vacuum pressure for the accurate detection of bacteria from water samples seeded with Escherichia coli. We observed that the number of E. coli detected increased with increasing vacuum pressure. In order to examine the retention rate of bacteria in the holes of the membranes under the different pressures, the membrane filters were removed after filtration, washed with sterile water by vortexing, and placed on m-Endo agar plates. With all the filters tested, the number of E. coli retained within the filters at negative 600 mmHg was approximately 10 to $20\%$ higher than that obtained with 100 mmHg. These results demonstrate that the vacuum pressure exerted during the filtration procedure may affect the fixation of bacteria into some portions of openings in the membrane filter.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.510.2-511
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• 1986

The biotechnology including genetic engineering is expected to be applied to various fields of wastewater treatments in order to promote biological reaction rate, to grade up the effluent quality and to advance the stability of microorganisms against temperature, pH and toxic substances. The current topics in Japan on application of biotechnology to wastewater treatment will be reviewed at the beginning of the presentation. Next, the research of Biochemical Engineering Laboratory is to be presented, especially focused on the following subjects ; (1) Application of genetic engineering to the investiation of heavy metal uptake by the resistant bacteria of Hg Cd or Zn. (2) Relationship between sulfate reducing bacteria and wastewater treatment, offensive odor and corrosion of sewer tranks.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.408-413
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• 2007

Putrescine has a negative effect on health and is also used as an indicator of quality on meat products. We investigated the genes involved in putrescine production by Serratia liquefaciens IFI65 isolated from a spoiled Spanish dry-cured ham. We report here the genetic organization of its ornithine decarboxylase encoding region. The 5,506-bp DNA region showed the presence of three complete and two partial open reading frames. Putative functions have been assigned to several gene products by sequence comparison with proteins included in the databases. The second gene putatively coded for an ornithine decarboxylase. The functionality of this decarboxylase has been experimentally demonstrated by complementation to an E. coli defective mutant. Based on sequence comparisons of some enterobacterial ornithine decarboxylase regions, we have elaborated a hypothetical pathway for the acquisition of putrescine biosynthetic genes in some Enterobacteriaceae strains.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.265-270
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• 2009

An oligonucleotide array was developed to detect and genotype mollicutes based on the internal transcribed spacer (ITS) sequence. The results of the assay were compared with those of a PCR-RFLP assay. The proposed oligonucleotide array containing 5 genus- and 23 species-specific probes was able to detect Mycoplasma species, including M. penetrans and M. spermatophilum, that were not detected by the PCR-RFLP assay. Therefore, the results demonstrated that the proposed oligonucleotide array was effective for the detection and discrimination of 23 species, including an acholeplasma, 21 mycoplasmas, and a ureaplasma, and showed promise as a countermeasure to ensure that biological products are safe and of good quality.

• Journal of Microbiology and Biotechnology
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• v.5 no.5
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• pp.274-279
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• 1995

Ethyl caproate, one of the major flavor compounds deciding the quality of sake (Japanese wine), is produced during the brewing by the action of alcohol acyltransferase and esterases of sake yeast and koji mold. Extracellular esterases of Aspergillus oryzae required for ethyl caproate synthesis were purified partially. The enzymes had different optimum pH and affinity toward substrates. Substrate preferences and inhibition features showed the three enzymes to be B-type esterases or carboxylesterases (EC 3.1.1.1).

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.645-654
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• 1989

The historical background of fish fermentation in Asia and other regions of the world is reviewed. The classification of fermented fish products in different regions is attempted with respect to the technology involved. The fermented fish products are largely divided into three groups; (1) high-salt, (2) low-salt, and (3) non-salt fermented. High-salt fermented products contain over 20％ of salt and are represented by fish sauce, cured fish and fish paste. Low-salt fermented products contain 6-18％ salt and are subdivided into lactic fermented products with added carbohydrate and acid pickling associated with low temperature. Non-salt fermented products are represented by the solid state bonito fermentation and some alkaline fermentation of flat fishes. The local names of the products in different regions are compared and classified accordingly. The microbial and biochemical changes during fish fermentation are considered in relation to the quality of the products, and their wholesomeness is reviewed.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.113-117
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• 1999

As a basic study for quality improvement of Korean soybean paste and soybean sauce, we investigated on microflora of soybean paste and soybean sauce fermentation. Major Microorganisms were isolated from the sample pastes and sauces, and identified systematically. Selected Microorganisms were identified by MIS whole cell fatty acid analysis by gas chromatography. Identification results showed that Bacillus licheniformis, bacillus pumilis and Bacillus subtilis were dominant in soybean paste and Staphylococcus vitulus, Bacillus subtilis, Bacillus pumilus, and Lactobacillus fermentum were dominant in soybean sauce. It seemed that these Microorganisms played an important role in soybean paste and soybean sauce fermentation and could be used for the further studies such as protease and amylase activities.