• Journal of Microbiology and Biotechnology
• /
• 제5권2호
• /
• pp.114-116
• /
• 1995

Concentrated Brazillian sugar cane stillage was used as a substrate for the yeast biomass production using Candida rugosa isolated from East Africa. At the optimum stillage concentration of 10% dry matter, biomass production was 20.4 g/l and COD reduction rate was 41%. The specific growth rate of the yeast was 0.17 $h^{-1}$ and the corresponding productivity 0.91 g $l{-1} h^{-1}$ in the batch fermentation was observed at $40{\circ}^C$.

• 한국미생물·생명공학회지
• /
• 제21권3호
• /
• pp.281-287
• /
• 1993

Rye stillage was adopted as a substrate for the production of yeast biomass by a thermotolerant yeast Candida rugosa isolated from East Africa. In the batch fermentation, the yield of biomass and crude protein reached 4.9-8.4g/l and 2.2-3.5g/l, respectively, the rate of COD reduction was about 20%. Over 90% amount of main components such as glycerol and lactic acid were assimilated, but protein assimilation reached only to 38-45% of the initial content. Crude protein content of the dry yeast biomass produced was 42-47% and sulfur-containing amino acid was revealed as limiting essential amino acid.

• 유기물자원화
• /
• 제12권3호
• /
• pp.119-125
• /
• 2004

사탕무즙을 이용한 알콜생산에서 배출되는 증류폐액(sugar beet stillage)을 기질로 고온성 효모인 Candida rugosa를 이용해 단세포단백을 생산 할 때 기질의 최적화와 COD 감소를 연구하였다. 인의 첨가는 실험에 사용된 3가지 모든 시료기질에 꼭 필요한 것으로 나타났고 질소첨가는 기질의 잔당농도가 높을 경우에 필요하였다. 모든 시료에 있어서 인의 첨가는 생균생산율(Biomass production)을 23-61% 까지 크게 높였다. 이에 비해 질소의 첨가는 잔당함량이 높을 경우 생균생산율을 약간 상승시켰으나 질소와 함께 첨가할 경우 90%까지 크게 높였다. COD는 인의 첨가로 인해 26-46%까지 더 감소되었으며 질소와 함께 첨가할 경우 85%까지 크게 감소되었다.

• 한국수산과학회지
• /
• 제29권6호
• /
• pp.882-887
• /
• 1996

Production of yeast diet has been carried out in batch fermenters under optimum culture conditions. The fermentation of Candida utilis on a $2\%$ complex medium resulted in 1.22 g/L/h productivity and $65\times10^8$ viable cells/ml, and the addition of $15{\mu}M$ zinc to the medium increased both the productivity and the number of viable cells just a little more. In the case of the fermentation of Kluyveromyces fragilis, the highest value of the biomass productivity, 1.94 g/L/h, was obtained on a $2.5\%$ fructose medium with $70\times10^8$ viable cells/ml, and $1\%$ peptone was found to be a growth factor in this fermentation. When $3.5\%$ NaCl was added to the given medium, both the biomass productivity and the number of viable cells decreased significantly in each fermentation, but this may be considered to preserve yeast diet long without osmotic lysis.

• 한국식품영양과학회지
• /
• 제21권3호
• /
• pp.263-269
• /
• 1992

무청즙액을 식물녹엽단백질의 생산과 효모의 균체생산을 위한 두가지 목적으로 이용하는 연구를 하였다. 무청즙액을 80-10$0^{\circ}C$로 가열하거나 pH를 조정하여 침전시켰을 때 침전물의 양은 모두 무청즙액 1리터당 10.0-16.5g(평균 13.5g)이었고 이 침전물의 조단백질 함량은 25-30%이었다. 단백질을 침전시켜 제거한 여액은 전당의 함량이 1.0%정도 되게 희석하여 효모 Candida utilis를 배양하였을 때 무청 여액원액 1리터당 최고 19.59의 효모균체를 생산할 수 있었다. 따라서 무청즙액 1리터로부터 생산할 수 있는 고단백질자원은 33g이었다.

• Journal of Ginseng Research
• /
• 제33권3호
• /
• pp.183-188
• /
• 2009

To produce ginsenoside-Rg$_3$ enriched edible yeast, ginseng steaming effluent (GSE) was used for yeast cultivation in this study. Four kinds of edible yeasts were cultured in sterilized GSE (2% w/v, pH 6.5), without any nutrient, for 48 h at 30$^{\circ}C$, and their growth and ginsenoside compositions were determined. Among the yeasts, Saccharomyces cerevisiae showed the highest growth in the GSE medium. 267.1 mg of Saccharomyces cerevisiae biomass was produced from 1 g of GSE solid and ginsenoside-Rg$_3$ contents was determined with 0.033 mg. Saccharomyces cerevisiae also showed the best overall acceptability, with a herbal and fermentative flavor and a slightly bitter taste. From these data, we conclude that Saccharomyces cerevisiae is the excellent strain for production of ginsenoside-Rg$_3$ enriched edible yeast using GSE.

• Journal of Microbiology and Biotechnology
• /
• 제19권2호
• /
• pp.161-166
• /
• 2009

Certain microalgae have been known to use light and various carbon sources to produce carbohydrates, mainly in the form of starch. This is one of the pertinent feedstocks replacing agricultural products for the production of bioethanol by yeast. This study focuses upon dilute acid hydrothermal pretreatments at low cost and high efficiency to compete with current methods, and employs Chlamydomonas reinhardtii UTEX 90 as the feedstock. With dry cells of 5%(w/v), the algal biomass was pretreated with sulfuric acid(1-5%) under temperatures from 100 to $120^{\circ}C$, from 15 to 120 min. As a result, the glucose release from the biomass was maximum at 58%(w/w) after pretreatment with 3% sulfuric acid at $110^{\circ}C$ for 30 min. This method enabled not only starch, but also the hydrolysis of other oligosaccharides in the algal cell in high efficiency. Arrhenius-type of model equation enabled extrapolation of some yields of glucose beyond this range. The pretreated slurry was fermented by yeast, Saccharomyces cerevisiae S288C, resulting in an ethanol yield of 29.2% from algal biomass. This study suggests that the pretreated algal biomass is a suitable feedstock for ethanol production and can have a positive impact on large-scale applied systems.

• Journal of Microbiology and Biotechnology
• /
• 제31권5호
• /
• pp.717-725
• /
• 2021

This study aimed to optimize medium composition and culture conditions for enhancing the biomass of Lactobacillus plantarum 200655 using statistical methods. The one-factor-at-a-time (OFAT) method was used to screen the six carbon sources (glucose, sucrose, maltose, fructose, lactose, and galactose) and six nitrogen sources (peptone, tryptone, soytone, yeast extract, beef extract, and malt extract). Based on the OFAT results, six factors were selected for the Plackett-Burman design (PBD) to evaluate whether the variables had significant effects on the biomass. Maltose, yeast extract, and soytone were assessed as critical factors and therefore applied to response surface methodology (RSM). The optimal medium composition by RSM was composed of 31.29 g/l maltose, 30.27 g/l yeast extract, 39.43 g/l soytone, 5 g/l sodium acetate, 2 g/l K₂HPO₄, 1 g/l Tween 80, 0.1 g/l MgSO₄·7H₂O, and 0.05 g/l MnSO₄·H₂O, and the maximum biomass was predicted to be 3.951 g/l. Under the optimized medium, the biomass of L. plantarum 200655 was 3.845 g/l, which was similar to the predicted value and 1.58-fold higher than that of the unoptimized medium (2.429 g/l). Furthermore, the biomass increased to 4.505 g/l under optimized cultivation conditions. For lab-scale bioreactor validation, batch fermentation was conducted with a 5-L bioreactor containing 3.5 L of optimized medium. As a result, the highest yield of biomass (5.866 g/l) was obtained after 18 h of incubation at 30℃, pH 6.5, and 200 rpm. In conclusion, mass production by L. plantarum 200655 could be enhanced to obtain higher yields than that in MRS medium

• 한국식품영양과학회지
• /
• 제24권3호
• /
• pp.434-439
• /
• 1995

단세포 단백질 자원으로 이용 가능한 균주로 알려진 Candida utilis ATCC 42416 균체를 생산하기 위하여 무를 파쇄하여 얻은 무즙을 배지로 균체배양 실험을 하였다. 무즙의 수용성 고형물과 총 당량은 각각 5.0~8.8 Brix와 3.5~6.5%였다. C. utilis ATCC 42416 균주를 무즙에 접종하여 $30^{\circ}C$에서 200rpm으로 진탕 배양하였을 때 24시간 이내에 증식이 끝났으며, 단위 소모당에 대한 최대 균체 생산량은 당농도 1% 회석 무즙에서 L당($5\;\times\;DCRI$) 21.5g의 건조균체를 생산하였다. 5배 회석무즙에 약간의 영양소 glucose(2.0%), yeast extract(0.2%), peptone(0.2%), ammonium sulfate(0.2%) 및 $KH_2PO_4(0.2%)$ 등을 각각 보강하여도 증식 속도, 균체생산 및 세포 단백질 함량 등에 차이가 거의 없어서 무즙자체가 C. utilis ATCC 42416 균체 생산에 좋은 기질이었음을 알 수 있다.

• Journal of Animal Science and Technology
• /
• 제63권3호
• /
• pp.603-613
• /
• 2021

This research improved the growth potential of Bifidobacterium animalis subsp lactis strain JNU306, a commercial medium that is appropriate for large-scale production, in yeast extract, soy peptone, glucose, L-cysteine, and ferrous sulfate. Response surface methodology (RSM) was used to optimize the components of this medium, using a central composite design and subsequent analyses. A second-order polynomial regression model, which was fitted to the data at first, significantly lacked fitness. Thus, through further analyses, the model with linear and quadratic terms plus two-way, three-way, and four-way interactions was selected as the final model. Through this model, the optimized medium composition was found as 2.8791% yeast extract, 2.8030% peptone soy, 0.6196% glucose, 0.2823% L-cysteine, and 0.0055% ferrous sulfate, w/v. This optimized medium ensured that the maximum biomass was no lower than the biomass from the commonly used blood-liver (BL) medium. The application of RSM improved the biomass production of this strain in a more cost-effective way by creating an optimum medium. This result shows that B. animalis subsp lactis JNU306 may be used as a commercial starter culture in manufacturing probiotics, including dairy products.