• 한국축산식품학회지
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• 제32권4호
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• pp.409-413
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• 2012

This study aimed to compare the probiotic characteristics of twelve strains of Lactobacillus acidophilus including cholesterol assimilation and conjugated linoleic acid (CLA) production. Cholesterol assimilation exhibited some variation among L. acidophilus strains, which could be classified into three groups based on their assimilation levels (p<0.05). The high cholesterol assimilation group exhibited a significantly higher tolerance to 0.3 and 0.5% bile acid than the low cholesterol assimilation group (p<0.05). Cholesterol assimilation showed positive correlation with 0.5% bile tolerance, and a negative correlation with acid tolerance (p<0.01). Glycocholate deconjugation activity showed no relationship with cholesterol assimilation, whereas taurocholate deconjugation activity was shown to have negative correlation with cholesterol assimilation (p<0.05). CLA production by L. acidophilus strains exhibited a wide variation, ranging from 2.69 to 5.04 mg/g fat. CLA production of L. acidophilus GP1B was the highest among the tested strains, but there was no evidence for differences in CLA production in strain specificity. Based on these results, the cholesterol assimilation of L. acidophilus strains may not be related to deconjugation activity, but may in-fact be attributed to their bile-tolerance.

• KSBB Journal
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• 제15권4호
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• pp.359-365
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• 2000

Three lactic acid bacteria (C-1 K-3 and T-1 strain) were isolated from Nuruk and characterized subsequently. They were useful strains for production of lactic acid and their growth was inhibited at 10% ethanol pH 4 These strains were identified as lactococcus lactis subsp. lactis NR C-1 Leuconostoc mesenteroides subsp. mesenterides NR K-3 and pediococcus pentosaceus NR T-1 respectively by morphological physiological and biochemical characterization Lac lactis subsp lactis NR C-1 showed the highest lactic acid productivity. Leu measenteroides subsp mesenteroides NR K-3 showed stable lactic acid productivity and its growth was inhibited at pH 4. P pentosaceus NR T-1 had lower lactic acid productivity than the other two bacteria but it could not grow at 10% ethanol pH 4 The lactic acid productivity of these three strains in MRS broth were higher than that in Skim milk media the optimum pH and temperature for the lactic acid production of the three strains were 30-32$^{\circ}C$ and pH 6.0∼6.8 Glucose was the optimal carbon souorce for the lactic acid production. In terms of antagonism lac lactis subsp lactis NR c-1 showed somewhat inhibitory efects against some Gram positive rod and cocci such as Lactobacillus brevis and Streptococcus mitis. And Leu mesenteroides subsp mesenteroides NR K-3 showed the inhibitory effects against Streptococcus mitis but P. pentosaceus NR T-1 didn't show any inhibitory effects against tested strains.

• 생명과학회지
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• 제14권1호
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• pp.167-173
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• 2004

Lactobacillus brevis BH-21의 균체를 고정화하여 column형 reactor를 이용하여 $\gamma$-aminobutyric acid의 연속적 생산을 검토하였다. Lactobacillus brevis BH-21에 의한 $\gamma$-aminobutyric acid 생산조건은 고정화 담체로는 3.0% sodium alginate가 좋았고 직경 2.2 mm의 bead를 사용하여 기질의 주입속도는 10 mL/h이 최적 조건이었다. Lactobacillus brevis BH-21의 고정화 균체와 유리 균체를 사용하여 $\gamma$-aminobutyric acid의 생산을 최적 조건하에서 1, 2, 3, 및 4차 발효 동안 48시간마다 신선한 기질을 주입하면서 비교ㆍ조사한 결과 고정화 균체를 사용 시에 생산량이 더 많았다. Column형 reactor에 의한 연속 발효 시 발효 25일까지 생산이 우수하였고 발효 30일까지는 $\gamma$-aminobutyric acid를 생산할 수 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.228-231
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• 2002

Itaconic acid has been produced during the cutivation of Aspergillus terreus DSMZ 5770 by using several starchs as carbon sources. The starchs were pretreated by partial hydrolysis with some acids at various pH conditions. The highest yield for the production of itaconic acid has been found when rice starch was pretreated by sulfonic acid at pH 2.5 and utilized for the cultivation. Using the results from shaker fermentation A. terreus has been cultivated in 2.5 L bioreactor for the production of itaconic acid and its on-line monitoring.

• Journal of Microbiology and Biotechnology
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• 제1권2호
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• pp.130-135
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• 1991

The effects of media composition on citric acid fermentation using surface immobilized Saccharomycopsis lipolytica were studied. The use of the standard medium for these organisms resulted in rapid decrease of citric acid production and a transformation of immobilized cell morphologies from a yeast-type to a mycelium-type. When the standard medium was enriched with vitamins, trace minerals, a growth factor and ammonium to form a Vigorous Stationary Phase (VSP) fermentation type medium, relatively stable citric acid production (10 mg/lㆍh) was obtained. Using the VSP type medium, the surface immobilized cells also retained their yeast-type form.

• 미생물학회지
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• 제27권2호
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• pp.124-129
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• 1989

In order to improve the production of bacterial alginate, Azotobacter vinelandii NCIB 8789 was treated with 200.$\mu$g/ml of MNNG for obtaining mutant strain. The mutant HB18 was selected, which produced the highest amount of alginic acid among the survival stains. The HB18 produced 5.4g/l of alginic acid when batch cultured at $30^{\circ}C$ for 160 hrs and its alginic acid showed high molecular weight and simple composition when compared with thoseof wild type.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권5호
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• pp.252-262
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• 2002

The growing interest in the application of arachidonic acid (ARA) in various fields of health and dietary requirements has elicited much attention on the industrial production of ARA-containing oil by the cultivation of Mortierella fungi. For the industrial production of ARA, various studies, such as isolation of a high-potential strain and optimization of culture conditions, have been conducted. Studies including the investigation of morphology are important because ARA is accumulated in the mycelia, and thus cultivation with high biomass concentration is essential for obtaining a high ARA yield. Combining the results derived from various studies, a high ARA yield was attained in an industrial fermentor. These ARA production techniques are applicable to the production of other polyunsaturated fatty acids (PUFAs), and will contribute to the improvement of fermentation technology especially in the field of fungal cultivation.

• Korean Chemical Engineering Research
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• 제54권5호
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• pp.719-721
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• 2016

Formate has been considered as an environmentally sustainable feedstock that can be used to accelerate the production of valuable chemicals. This study presents brief results of the formatotrophic production of Poly-${\beta}$-hydroxybutyric acid (PHB) by Methylobacterium sp. To evaluate the production of PHB, five species of Methylobacteria were tested using formate as the sole carbon and energy source. Methylobacterium chloromethanicum CM4 exhibited the highest productivity of PHB, which showed 1.72 g/L PHB production, 32.4% PHB content, and 0.027 g-PHB/g-formate PHB yield. These results could be used for the formatotrophic production of PHB with the concurrent reduction of $CO_2$ to formate.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.338-341
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• 2000

An internal membrane bioreactor system was employed for continuous succinic ac id production from glucose in order to prove its performance and practicality. Succinic acid-producing Anaerobiospirillum succiniciproducens required more $CO_2$ for the proper growth and succinic acid production in cell recycled continuous culture than in batch culture. The maximum productivity obtained in cell recycled continuous culture was about 3.3 g/L-h which was ca. 3.3 times higher than that obtained in batch culture.

• 한국식품영양학회지
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• 제1권2호
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• pp.76-85
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• 1988

In order to obtain the basic data for the preparation of yogurt containing ginseng component, the effect of ginseng component on cell growth of Lactobacillus casei YIT 9018 and on lactic acid production were investigated. Initial cell growth and acid production were markedly inhibited by the addition of ethanol extracts in the level of 8% into 15% skim milk. Crude saponin did not show any inhibitory effect on cell growth and acid production, but ether layer fraction showed inhibitory effect. It was thought to be more advantageous to add ginseng extracts after the fermentation of milk than before. The addition of ginseng extract at 8% level into liquid yogurt was most suitable in organoleptic test. Cell viability was not affected by the addition of ethanol extracts up to 8% level during storage of liquid yogurt.