• Journal of Microbiology and Biotechnology
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• 제4권1호
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• pp.56-62
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• 1994

A yeast strain, BT001, which can directly ferment D-xylose to ethanol was isolated from forest soils, and then identified as Candida sp. Cultural conditions for the optimum ethanol production, along with the effects of aeration on cell growth and ethanol production were investigated. Aeration stimulated the cell growth and the volumetric rate of ethanol production, but decreased the ethanol yield. Optimum temperature and initial pH for the ethanol production were $33{\circ}^C$ and 6.0, respectively. In a shake flask culture, this strain produced 52.3 g ethanol per liter from 12%(w/v) D-xylose after incubation for 96 hours. Ethanol yield was 0.436 g per g D-xylose consumed. This corresponds to 85.8% of theoretical yield. Also, this yeast strain produced ethanol from D-galactose, D-glucose and D-mannose, but not from L-arabinose and L-rhamnose. Among these sugars, D-glucose was the fastest in being converted to ethanol sugars.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 추계학술대회 논문집(Proceeding of the KOSME 2001 Autumn Annual Meeting)
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• pp.45-49
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• 2001

To maintain the freshness of produce, because of stand away between produced and consumer, we need refrigeration system that can supply to consumer at cold chain as soon as gathering. General refrigeration system consist of refrigeration chamber or low temperature store. But the vacuum technology can rapidly refrigeration without refrigerator. This precool system possible to get low precooled temperature, suitable for the fishes, the meat, the vegetables, the fruit etc. Especially get advantage that quality maintain through rapid refrigeration of ferment directly generate heat. Vacuum precool system's principle is that water saturated temperature reduce according to pressure is get to vacuum area, so product temperature reduce as water evaporation at product. In vacuum suction, unit, on early experiment period run the rotary type vacuum pump at purpose pressure, then maintain pressure by water-diven ejector. As the results, cabbage took about 60 minutes to reach from $23.2^{\circ}C$ to $4.5^{\circ}C$at 5mgHg abs.

• 미생물과산업
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• 제18권3호
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• pp.23-33
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• 1992

The general characteristics of campylobacters and related organisms (e.g., species of the genera Helicobacter and Wolinella, Bacteroides ureolyticus, and Bacteroides gracilis) are as follows: slender, non-sporeforming, gram-negative, vibroid bacteria (helical- or spiral- shpaed; except that B. ureolyticus and B. gracilis are straight-rod), 0.2-0.5 .mu.m in width and 0.5 .mu.m in length. (Smibert, 1984; Penner, 1988). The species of genus Campylobacter and related organisms are chemoorganotrophs; however, they neither oxidize nor ferment carbohydrates and instead obtain energy from amino acids, the salts of tricarboxylic acids (TCA) cycle intermediates, the salts of organic acids, or, in some species, H$\_$2/. With regard to their oxygen responses for growth, they all are microaeophilic i.e., they are capable of oxygen-dependent growth (respiring with oxygen as a terminal electron acceptor) but can not grow in the presence of a level of oxygen equivalent to that present in an air atmosphere (21% oxygen). This review will take interests in how these microorganisms response to oxygen for growth and what repiratory types they have.

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.101-104
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• 1997

Lactic acid production from ${\alpha}$-cellulose by simultaneous saccharification and fermentation (SSF) was studied. The cellulose was converted in a batch SSF using cellulase enzyme Cytolase CL to produce glucose sugar and Lactobacillus delbrueckii to ferment the glucose to lactic acid. The effects of temperature, PH, yeast extract loading, and lactic acid inhibition were studied to determine the optimum conditions for the batch processing. Cellulose was converted efficiently to lactic acid, and enzymatic hydrolysis was the rate controlling step in the SSF. The highest conversion rate was obtained at 46$^{\circ}C$ and pH 5.0. The observed yield of lactic acid from ${\alpha}$-cellulose was 0.90 at 72 hours. The optimum pH of the SSF was coincident with that of enzymatic hydrolysis. The optimum temperature of the SSF was chosen as the highest temperature the microoraganism could withstand. The optimum yeast extract loading was found to be 2.5g/L. Lactic acid was observed to be inhibitory to the microorganisms' activity.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.69-74
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• 2012

This study was performed to determine by the ability of the mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus to ferment Dioscorea opposita Thunb. (yam) and to evaluate the nutraceutical value of fermented yam. The titratable acidity (TA) value increased from 2 to 6% with increased concentrations in both raw yam and extracted lactic acid bacteria (LAB) fermented yam (LFY). The viable cell counts and the allantoin and diosgenin contents were higher in raw LFY at large concentrations (6%) than in extracted LFY samples at all fermentation periods up to 32 h. Based on these data, it confirmed that raw yam fermented by the combination culture of L. bulgaricus and S. thermophilus for various fermentation periods favors the symbiotic growth of LAB and results in higher nutraceutical content.

• Food Science and Biotechnology
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• 제14권6호
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• pp.722-726
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• 2005

The use of isolated wine yeasts in winemaking processes is preferable to spontaneous fermentation. Selection criteria of wine yeast strains depend also on capacity and rate of fermentation and on alcohologenic capabilities. Our studies have described the dynamics of fermentation of wine musts by some isolated wine yeast strains of Saccharomyces genus: strains 6 and 8 of S. cerevisiae var. ellipsoideus (S. ellipsoideus) and strains 5 and 7 of S. bayanus var. oviformis (S. oviformis). All have high technological properties and all are adapted for the specific pedoclimatic conditions of some areas of Sibiu viticultural region. The selected strains were used as inocula to ferment Sauvignon, Muscat Ottonel, Rose Traminer, and Pino Gris musts in controlled laboratory conditions. It was found that higher initial oxygen concentration in must is necessary to accelerate the fermentation of all the wine yeast strains studied. In order to obtain quality wines, strains with considerable fermentative capacity, high alcohologenic capabilities, and a good conversion efficiency are recommended.

• 한국식품영양학회지
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• 제1권2호
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• pp.95-101
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• 1988

In order to produce lactic acid and calcium lactate very useful for foods and medical supplies, lactic acid fermentation was studied by Lactobacillus sporogenes, a spore forming lactic acid bacterium. When this bacterium was cultured aerobically in the spore forming medium, the spore forming rate was 96.0% as total cell number 20$\times$108/ml, spore number 19.2$\times$108/ml. One minute agitating every 1 hour in the flask culture, or agitation of 100rpm in the fermenter was most efficient to continue to ferment at 45$^{\circ}C$ for 4days in the fermentation medium containing 10% glucose as carbohydrate and CaCO3 as a neutralizing agent. This homofermentative lactic acid bacterium showed fermentation yield of 99.3% and more than 98.2% of the yield was L(+)-lactic acid.

• 한국미생물·생명공학회지
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• 제3권2호
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• pp.89-93
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• 1975

재내식 발효법에 협사한 조건하에서 맥주를 더욱 방률적으로 생산하기 위하여 발효개시 3일후에 일정양의 새로운 맥즙을 첨가시키고 나머지 발효를 4일내지 6일사이에 완성시켜 보았다. 그 결과 1/3 용량과 $\frac{1}{2}$ 용량의 새로운 맥즙을 체가하고 5일동안 더 발효한 맥주가 미각검사에 합격되므로써 종내외 9일간 발효에 비하여 각각 22%내지 28%의 방율증가가 可能하게 되었다.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1204-1206
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• 2021

Limosilactobacillus fermentum JN2019, formerly named Lactobacillus fermentum JN2019, was isolated from kimchi. Its genome was completely sequenced using the PacBio RSII sequencing system to explore beneficial phenotypes. In a previous study, L. fermentum JN2019 was used to ferment the by-product of tumeric for use in livestock feed. The 2.3 Mb genome had a high guanine (G) + cytosine (C) content of 50.6% and a 30 kb plasmid. The data will inform the comprehensive understanding of JN2019 and provide insights for potential applications.

• Journal of Microbiology and Biotechnology
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• 제29권3호
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• pp.339-346
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• 2019

L-Arabinose, a five carbon sugar, has not been considered as an important bioresource because most studies have focused on D-xylose, another type of five-carbon sugar that is prevalent as a monomeric structure of hemicellulose. In fact, L-arabinose is also an important monomer of hemicellulose, but its content is much more significant in pectin (3-22%, g/g pectin), which is considered an alternative biomass due to its low lignin content and mass production as juice-processing waste. This review presents native and engineered microorganisms that can ferment L-arabinose. Saccharomyces cerevisiae is highlighted as the most preferred engineering host for expressing a heterologous arabinose pathway for producing ethanol. Because metabolic engineering efforts have been limited so far, with this review as momentum, more attention to research is needed on the fermentation of L-arabinose as well as the utilization of pectin-rich biomass.