• KSBB Journal
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• v.14 no.5
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• pp.561-565
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• 1999

Optimum conditions for vacuum-drying ad cultivation of yeast cells for the production of active dry yeast were examined. At lower temperature, more drying time was required to dry the yeast pellet to reach the desirable water content(8%). Optimum temperature of vaccum oven and time for drying was 63$^{\circ}C$ and 90 min, respectively. Optimum medium composition for flask culture using cane molasses as the substrate were 0.25% sugar, 0.013% $K_2$HPO$_4$, 0.1% $K_2$HPO$_4$. and 0.125% (NH$_4$)$_2$SO$_4$. Culture temperature $25^{\circ}C$ gave the highest survival rate of dired yeast. After finishing fed-batch culture and the culture was left in the fermentor without adding any sugar or nutrient, survival of the dried yeast harvested from the fermentor increased to 86.0% after 36 hr. It was also observed that the yeast cells with higher budding rates showed lower survival rate.

• Animal Bioscience
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• v.36 no.1
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• pp.63-74
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• 2023

Objective: The objective of this study was to investigate the effects of feeding active dry yeast (ADY) and yeast culture (YC) on fecal bacterial community in finishing bulls fed high-concentrate diets in the same experimental environment. Methods: Forty-five healthy finishing cattle (Simmental×Chinese Luxi yellow bulls; 24 months; 505±29 kg) were randomly divided into three groups: i) CON group (control group, only fed basal diet), ii) ADY group (fed basal diet + active dry yeast), and iii) YC group (fed basal diet + yeast culture). At the end of the trial, nine rectum fecal samples were randomly selected from each group for bacterial DNA sequencing. Results: There was no difference among groups about alpha diversity indices (all p>0.05), including ACE, Chao 1, Shannon, and Simpson indices. Principal component analysis and non-metric multidimensional scaling analysis showed a high similarity among three groups. Compared with CON group, ADY and YC groups had greater relative abundance of c_Clostridia, o_Oscillospirales, and f_Oscillospiraceae, but lesser relative abundance of g_Megasphaera, and s_Megasphaera_elsdenii (all p<0.01). And, the relative abundances of p_Firmicutes (p = 0.03), s_Prevotella_sp (p = 0.03), o_Clostridiales (p<0.01), g_Clostridium (p<0.01), f_Caloramatoraceae (p<0.01), and f_Ruminococcaceae (p = 0.04) were increased in the ADY group. The PICRUSt2 prediction results showed that the metabolic pathways had no significant differences among groups (p>0.05). Besides, the relative abundance of c_Clostridia (r = 0.42), and f_Oscillospiraceae (r = 0.40) were positively correlated to average daily gain of finishing bulls (p<0.05). Conclusion: Both of ADY and YC had no effect on diversity of fecal bacteria in finishing bulls, but the supplementation of ADY and YC can improve the large intestinal function in finishing bulls by increasing the abundance of cellulolytic bacteria and altering the abundance of lactic acid-utilizing bacteria.

• The Korean Journal of Food And Nutrition
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• v.16 no.3
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• pp.203-208
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• 2003

In wine making, to perform yeast culture effectively that is the most important factor, 5 (Montrachet, Pasteur Champagne, Epernay II, prise de Mousse, Lalvin W15) representative active dry yeasts were selected. These are results about physicochemical properties. As a consequence of examining the survival rate in both 17% ethanol solution and 200ppm sulfite solution after 72 hours, Lalvin W15 strain was the highest among the 5 representative active dry yeasts. Moreover, in 1% citric acid solution, the survival rate of Pasteur Champagne after 72 hours was the highest one. As a result of experiment of red wine that is fermented by 5 different active dry yeasts, the highest one of total acidity was must of Lalvin W15. And then, the must of the Epernay II contains the highest ethanol content. Regarding of the content of organic acid, the wine that is fermented by Prise de mousse was the highest one and the order could be explained by Tartaric > Malic > Citric.

• KSBB Journal
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• v.17 no.2
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• pp.162-168
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• 2002

Human ferritin H- and L-chain genes(hfH and hfL) were cloned into the yeast shuttle vector YEp352 with various promoters, and the vectors constructed were used to transform Saccharomyces cerevisiae 2805. Three different promoters fused to hfH and hfL were used: galactokinase 1 (GAL1) promoter, glyceraldehyde-3-phosphate dehydrogenase(GPD) promoter and alcohol dehydrogenase 1(ADH1 ) promoter. SDS-polyacrylamide gel electrophoresis and Western blotting analyses displayed expression of the introduced hfH and hfL. In the production of both ferritin H and L subunits GAL1 promoter was more effective than GPD promoter or ADH1 promoter. Ferritin H and L subunits produced in S. cerevisiae were spontaneously assembled into its holoproteins as proven on native polyacrylamide gels. Both recombinant H and L-chain ferritins were catalytically active in forming iron core. When the cells were cultured in the medium containing 10 mM ferric citrate, the cell-associated concentration of iron was 174.9 $\mu\textrm{g}$ Per gram(dry cell weight) for the recombinant yeast YG-L and 148.8 $\mu\textrm{g}$ Per gram(dry cell weight) for the recombinant yeast YG-L but was 49.4 $\mu\textrm{g}$ Per gram(dry cell weight) in the wild type, indicating that the iron contents of yeast is improved by heterologous expression of human ferritin H-chain or L-chain genes.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.392-397
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• 2006

To compare the contents of amino acids in raspberry wine, 5 types of active dry yeast strains (Saccharomyces cerevisiae Montrachet (UCD #522), Saccharomyces bayanus Pasteur Champagne (UCD #595), Saccharomyces cerevisiae Epemay II (CEG), Saccharomyces bayanus Prise do Mousse (PM), Saccharomyces uvarum Latvia W15) were used. In the fermentation experiment two kinds of raspberry wine were used; Rubus coreanus Miquel(RCM), harvested in Gochang, and Rubus crataegifolius Bunge(RCB), harvested in Okcheon. In 5 kinds of RCM raspberry wines, total contents of 17 amino acids were found from $16.77mg/{\ell}$ in the fermented Prise de Mousse, the most amount, to $12.29mg/{\ell}$ in Lalvin W15, the lowest. The content of amino acid in the RCB raspberry wine fermented by Montrachet was approximately 5.5 times higher than that of the RCM raspberry wine; $90.55mg/{\ell}\;to\;16.54mg/{\ell}$. Cystine and isoleucine were detected $2.97mg/{\ell},\;0.34mg/{\ell}$, respectively, in the RCB raspberry wine but not detected in the RCM raspberry wine. The amount of alanine, aspartic acid, and serine in RCB raspberry wine were found approximately 14 to 20 times larger than that of RCM raspberry wine.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.302-308
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• 2005

To examine the difference in each ingredient between the yeast strain and two raspberry kinds (Rubus crataegifolius Bunge(RCB), Rubus coreanus Miquel(RCM)) in the making of raspberry wine, five active dry yeasts were selected. Regarding the RCM ethanol content, the raspberry wine fermented by Lalvin Wl5 was the highest, while those fermented by Prise de Mousse were the lowest. The pH of the RCM was $3.58\~3.63$, and Montrachet was the highest one of total acidity. In the case of nonflavonoid phenols, the RCM fermented by Montrachet was the highest one, and in the case of flavonoid phenol and total phenol, the RCM fermented by Epernay II was the highest. The content of organic acid in RCM were highest in the following order: citric acid > oxalic acid > malic acid, and tartaric acid was not detected at all. The average content of malic acid in RCM after malolactic fermentation was reduced by almost $65.5\%$, and the RCM fermented by Prise de Mousse, after malolactic fermentation, was $73.3\%$. This latter was the highest, while the RCM fermented by Epernay II was the lowest, at $59.1\%$.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.450-457
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• 2004

In wine making, to perform yeast culture effectively, which is the most important factor, 5 strains of representative active dry yeasts were selected : Montrachet, Pasteur Champagne, Epernay II, Prise do Mousse, Lalvin W15. The results about fermentation properties were as follows. After 1 day of fermentation, the ethanol contents of Lalvin W15 wine and Montrachet wine were 5.4% and 4.0%. After 2 days of fermentation, the ethanol content of Lalvin W15 wine was 9.2%, which is the highest degree among all experimental groups. As for the content of sugar solution, the wine fermented by Lalvin W15 was the highest one. In acidic solution, fermentation activity of Prise de Mousse, Lalvin W15, Montrachet were highest degrees and Red wine fermentation activity of Prise de Mousse has shown the highest degree in its fermentation activity, if only initial SO$_2$ amounts were 200 ppm. In regard to the foaming tendency during fermentation, the size of foams in Montrachet was big and the amount of foams was a lot. The change in Brix during the fermentation became evident after two days. The Brix of Montrachet wine and Lalvin W15 wine was 3.0, a high initial fermentation speed. After 10 days of fermentation, total acidity of Lalvin W15 wine was 0.99g/100m1, the highest degree. After 3 days of fermentation, the ethanol content of Lalvin W15 wine was 7.4%, the highest degree. But after 9 days of fermentation Epernay II showed the higher ethanol concentration to 13.8%.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.856-863
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• 2013

An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane ($CH_4$) production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress $CH_4$ production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells), control (no live yeast cells) and yeast (YST) supplementation groups (supplemented with live yeast cells, YST1 or YST2). The yeast cultures contained $1.8{\times}10^{10}$ cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc${\times}$Landrace${\times}$Yorkshire pigs, mixed with a phosphate buffer (1:2), and incubated anaerobically at $39^{\circ}C$ for 24 h using 500 mg substrate (dry matter (DM) basis). Total gas and $CH_4$ production decreased (p<0.05) with supplementation of yeast. The methane production reduction potential (MRP) was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD) and total volatile fatty acids (VFA) concentration increased (p<0.05) in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05), but that of acetate decreased (p<0.05), which led to a decreased (p<0.05) acetate: propionate (A: P) ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05) with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05) with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro $CH_4$ production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic bacteria, both of which serve as a competitive pathway for the available H2 resulting in the reduction of methanogenic archaea.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.739-742
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• 2010

In order to select a superior yeast, 8 kinds of commercial active dry yeasts (Lalvin 1116, Lalvin 1118, Lalvin D-47, Lalvin Bourgovin, Parisienne, Fermivin, Red Star Monrachet, and Red Star Premier Cuvee) were utilized for omija wine fermentation. During fermentation, the physicochemical characteristics and sensory properties of the various omija wines were evaluated. According to the results, pH and titratable acidity were in ranges of 3.0-3.3% and 1.8-2.4%, respectively. Sugar content was $24^{\circ}Bx$ at early fermentation and changed to $8.4-10.2^{\circ}Bx$ at 24 days of fermentation. While the omija wines fermented by Lalvin D-47 and Red Star Premier Cuvee showed the highest alcohol contents (13.0%), the omija wine fermented by Parisienne showed the lowest alcohol content (10.8%). The omija wine fermented by Lalvin 1118 had an alcohol content of 12.0% and showed the lowest yeast count of 5.8 log CFU/mL. Hunter's values (L, a, and b) were all different among the 8 omija wines. Moreover, the omija wine fermented by Lalvin 1118 showed the highest scores for taste ($6.75{\pm}1.68$), swallowing ($6.65{\pm}1.50$), and overall acceptability ($6.70{\pm}1.34$). It is concluded that Lalvin 1118 was the best yeast among 8 tested commercial active dry yeasts, having a high potential for omija wine fermentation.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1053-1056
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• 2011

Optimal conditions for a high cell density fermentation were investigated in a recombinant Escherichia coli producing salmosin, a platelet aggregation inhibitor. The optimized carbon and nitrogen sources were glycerol 10 g/l, yeast extract 30 g/l, and bacto-tryptone 10 g/l, yielding the dry cell weight (DCW) of 10.61 g/l in a 500 ml flask culture. The late-stage induction with 1% L-arabinose in a 5 l jar fermentor showed the highest DCW of 65.70 g/l after 27 h of the fed-batch fermentation. Around 2,200 mg/l of the protein was expressed as an inclusion body that was then refolded to obtain the active salmosin of 96 mg/l. We also confirmed the inhibitory activity against platelet aggregation of the active salmosin from the high cell density fermentation.