• Journal of Microbiology
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• v.42 no.2
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• pp.133-138
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• 2004

This study was aimed to determine the accumulation of free fatty acid by mesophilic lactic acid bac-teria (Lactococcus lactis subsp. lactis 1471, Lactococcus lactis subsp. cremoris 1000 and Lactobacillus casei 111) in cold-stored milk. According to the results, all cold-stored milks had higher acid degree val-ues than those of fresh milk. This phenomenon showed that a slight increase occurred in the accumulation of free fatty acids as a result of spontaneous lipolysis during cold storage. All lactic acid bacteria showed good performance in production of titratable acidity, which increased during fermentation of the milk (fresh and stored milks). Moreover, as the storage time was prolonged, more free fatty acid accumulation was obtained from the fermentation of the cold-stored milk by the investigated lactic acid bacteria. The control milk, which was without lactic acid bacteria, showed no change in the accumulation of free fatty acid during fermentation. From this result, it can be suggested that longer cold-storage time can induce higher free fatty acid accumulation in milk by lactic acid bacteria.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.55-60
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• 1967

Studies on the changes of methanol content in the manufacturing process of apple wine and apple brandy. The results from the studies of transition and changes of methanol content in the fermentation of wine and brandy from Korean apple, Kugkwang and Iwai are as follows. 1) Pectin, the source of methanol, can be extracted as dregs more than 85% of its in the process of pressing to get juice. 2) In the process of fermenting wine, the occurence of methanol depends on the condition of the apple itself (i.e. species, freshness, change in quality, or corruption). It seems that the insoluble pectin in the fresh apples changes into the soluble pectin as time goes by. 3) The heating treatment of fresh apples produced more methanol compared with nonheating treatment. 4) The content of methanol in apple brandy can influence free methanol content in mash pulp.

• Journal of Microbiology
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• v.33 no.3
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• pp.222-227
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• 1995

We have examined DNase I sensitivity of .betha.-tubulin and flagellar calmodulin genes which are transiently and coordinately activated differentiation of Naegleria gruberi amebae into flagellates. The DNase I sensitivity of .betha.-tubulin and flagellar calmodulin genes changed in parallel with the changes in transcriptional activity of the respective genes during differentiation. The two genes were resistant to DNase I inamebae stage when transcription of the two genes was inactive. Forthy minutes after initiation of differentiation, when the two genes were most actively being transcribed, the two genes showed the highest sensitsivity to DNase I. One hundred and twenty minutes after initiation, the differentiation was completed and transcriptional activity of the two genes decreased to a low level. At this stage, the two genes were resistant to DNase I treatment like the ones at the amebae stage. This change in the DNase I sensitivity of the two genes was not observed when transcription of the two genes was blocked by adding cycloheximide at the beginning of differentiation.

• Journal of Microbiology
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• v.33 no.3
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• pp.252-259
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• 1995

The PCR was employed to detect and characterize the bovine immunodeficiency-like virus (BIV), which is a newly recognized member of the I entivirinae of the retroviruses. Degenerate primers representing the conserved regions in the pol genes of the Lentivirinae, were used to detect proviral DNA obtained from the bovine embryonic spleen cell cultures infected with BIV. The PCR amplified DNA fragment was molecularly cloned and sequenced. The BIV DNA fragment contained a sequence identical to that reported by Garvey et al. (Garvey et al., 1990. Virology, 175, 391-409). With the degenerate primers, peripheral blood mononuclear cells (PBMCs) of sick cattle and cells cultured with BIV were tested to determine genetic variation of BIV pol conserved sequence. We found the sequence heterogeneity within cultures and most variations occurred at the third base of codons that would not lead to amino acid substitutions. Another change was GAG (Glu) to AAG (Lys) within the BIV isolates. Interestingly, the altered sequence is also found in other lentiviruses such as HIV-2, SIV mac, CAEV and EIAV.

• Korean Journal of Microbiology
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• v.22 no.2
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• pp.97-101
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• 1984

To investigate the biodegradation pattern of rice straw, mainly composed of cellulose, hemicellulose and lignin components, by the isolate stran Bacillus subtilis $DO_4$, the change of cell population was observed on CMC (carboxymethyl cellulose), larch wood xylan and lignosulfonate as a carbon source respectively. Also, the transition pattern of enzyme activities of cellulase and xylanase and lignin contents was measured on rice straw and mixed substrate according to growth. The results in these experiments revealed that xylanase activity was first appeared and cellulase activity in the next, while lignin component was almost not changed through the culture period.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.38-45
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• 1986

Effect of sodium deoxycholate and sodium dodecyl sulfate on Rhizopus oryzae were investigated. Morphological change was obtained by supplement of these surfactants into culture media during the sumerged culture. In accordance with morphological changes, composition of phospholipid was changed. In case of surfactant-free culture, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine were measured more than 95% of total phospholipid. But cardiolipin and phosphatidylinositol were conspicuously increased by treatment of both sufactants. Presence of phospolipase A, C, and D were detected from mycelium. Phospholipase A and D were activated by supplement of sodium deoxycholate and C was activated by sodium dodecyl sulfate. These results were interpreted in respect of polymorphism of phospholipid and membrane stability against solubilization effect of surfactants.

• Journal of Microbiology
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• v.41 no.4
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• pp.335-339
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• 2003

Many genetic variants of ${\alpha}_1$-antitrypsin have been associated with early onset emphysema and liver cirrhosis. However, the detailed structural basis of pathogenic ${\alpha}_1$-antitrypsin molecules is rarely known. Here we found that a recombinant $M_{malton}$ variant (Phe52-deleted) lost inhibitory activity by spontaneous conformational conversion into a more stable, inactive form under physiological conditions. Biochemical and spectroscopic data suggested that the variant converts into a reactive center loop-inserted conformation, resembling the latent form of plasminogen activator inhibitor-1.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.413-413
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• 2023

Wetlands are a critical component of the global carbon cycle and are essential in mitigating climate change. Accurately quantifying wetland carbon emissions is crucial for understanding and predicting the impact of wetlands on the global carbon budget. The uncertainty quantifying carbon in wetlands may comes from the ecosystem's hydrological, biochemical, and microbiological variability. The Community Land Model is a sophisticated and flexible land surface model that offers several configuration options such as energy and water fluxes, vegetation dynamics, and biogeochemical cycling, necessitating careful consideration for the alternative configurations before model implementation to develop a practical model framework. We conducted a systematic literature review, analyzing the alternatives, focusing on the carbon stock pools configurations and the parameters with significant sensitivity for carbon quantification in wetlands. In addition, we evaluated the feasibility and availability of in situ observation data necessary for validating the different alternatives. This analysis identified the most suitable option for our study site, the Binbong Wetland, in Korea.

• Journal of Korean Academy of Dental Administration
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• v.6 no.1
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• pp.1-10
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• 2018

Prior to the end of the 20th century, microorganism research was limited to culture and has since been revolutionized by genetic analysis. Microorganisms, including bacteria, can cause disease, but most of them are commensal microorganisms in our bodies. This knowledge changes the pathological approach to infectious diseases and lends to a new perspective on the effects of gut and oral microorganisms on disease and health. The oral cavity, particularly the periodontal pocket, is considered to be a reservoir of microbes that cause disease, and oral microbial control is becoming more important. In this review, I will examine the changes in the microbiological revolution and the meaning of oral healthcare management based on those changes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1886-1891
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• 2013

To inactivate the microorganisms on the surface of blueberries after harvest and to secure microbial safety, a bubble-aqueous chlorine dioxide washing system was developed. After treating the freshly prepared blueberries with the bubble-aqueous chlorine dioxide washing system, the changes in the microbial populations and quality of the blueberries were determined during storage $4{\pm}1^{\circ}C$. Microbiological data indicated that the populations of total aerobic bacteria, yeast and mold decreased by 1.4 and 1.3 log CFU/g at the treatment of 20 ppm aqueous chlorine dioxide with the system, respectively. There was no significant difference in color change and weight loss during storage among treatments. In addition, this washing system could handle approximately 60 kg of blueberry per hour, resulting in labor-saving. Therefore, these results clearly suggest that the bubble-aqueous chlorine dioxide washing system could be useful in improving the microbiological safety of fresh blueberries after harvest.