• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.665-673
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• 2012

A balance trial experiment was carried out to evaluate the potential relationship between an enzymatically hydrolyzed yeast (EHY) and yeast culture combined with a live Bacillus subtilis (Bs) on the productive parameters, ileal digestibility, retention of nutrient and energy and villus morphology in broilers. Seventy two 28 d old, Ross B308 male broilers were assigned to a factorial combination of 2 levels of EHY (0 and 1 kg/ton of feed) and 2 levels of Bs (0 and 125 g/ton of feed). The experiment lasted 2 weeks. Several treatment interactions were observed. EHY-fed broilers showed the lowest feed intake and feed conversion ratio whereas Bs-fed broilers showed the highest feed intake and intermediate feed conversion ratio (EHY and BS interaction, p<0.05). Also, EHY-fed broilers had greater ileal digestibility of dry matter (EHY and BS interaction, p<0.01) and energy (EHY and BS interaction, p<0.05) but these responses were counterbalanced by the combination of EHY and Bs. The thickness of the mucosa was similar between the control and EHY-fed broilers, but was lowest when Bs was added alone (EHY and BS interaction, p<0.01). The thickness of the villus was greater in EHY plus Bs-fed broilers, intermediate for the control and lower for Bs or EHY-fed broilers (EHY and BS interaction, p<0.05). The area of the villus was greater in the control and EHY plus Bs-fed broilers (EHY and BS interaction, p<0.05). In addition, EHY-fed broilers showed greater breast yield and nitrogen retention (p<0.01) and ashes digestibility (p<0.05). On the other hand, Bs-fed broilers had greater carcass and breast weight, nitrogen retention, energy excretion and villus height (p<0.05). In summary, EHY and Bs enhanced some growth, carcass and nutrient retention responses, but did not show any synergic relationship in these responses. Opposite to this, the results suggest that the positive effect of EHY on the feed conversion and digestibility of nutrients were counterbalanced by the addition of Bs.

• Korean Journal of Organic Agriculture
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• v.23 no.3
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• pp.523-534
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• 2015

Twenty four Holstein steers (average body weight $714{\pm}13.60kg$) were used in this experiment to determine the effect of supplementing of microbial culture and coated vitamin-C on growth performances and carcass characteristics in finishing Holstein steers. Holstein steers were randomly assigned to feeding groups of control group (Con, 12 kg of basal diet/head/day), microbial culture group (MC, 12 kg of basal diet + 30 g of microbial culture/head/day) and coated vitamin-C group (CVC, 12 kg of basal diet + 10 g of coated vitamin-C/head/day). MC and CVC groups were higher in ADG compared to control (P<0.05). FCR was also lower in MC and CVC groups than control group (P<0.05). Back fat thickness, rib-eye area, marbling score, meat color and yield index were not changed by supplementing microbial culture and coated vitamin-C. MC group was higher for maturity compared to control and CVC group (P<0.05). CVC group was higher for fat color compared to control and MC group (P<0.05). Based on the results obtained from the current study, supplementation of microbial culture and coated vitamin-C as an alternative to antibiotic might increase growth performances and enhance carcass characteristics in finishing Holstein steers. However, more studies are needed to find out the optimum supplementing period of microbial culture or coated vitamin-C for high quality meat production from Holstein steers.

• Journal of Life Science
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• v.6 no.2
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• pp.135-141
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• 1996

Possible yeast strains that could be used as feed for aquaculture were studied. It was shown that the maximum specific growth rate and the biomass yield of Kluyveromyces fragilis yeast and Candida utilis yeast under optimum pH and temperature were much higher than those of Saccharomyces cervisiae yeast which had been as established yeast diet for rotifer culture. Hence, this work was focussed on the growth characteristics of the two yeasts through flask dultures for mass production. With 5% inoculum dosage, the best values of $\mu$$_{max}$ and OD$_{max}$ were obtained with on 2.5% fructose medium and 2% YE medium for K. fragilis and C. utilis, respectively, where the values of $\mu$$_{max}$ and OD$_{max}$ were found to be 0.73 hr$^{-1}$ and 3.00 for K. fragilis and 0.59 hr$^{-1}$ and 2.80 for C. utilis. It was also found that the lag phase of the growth incresed with increasing initial zinc and NaCl concentrations and decreased with increasing inoculum dosage. Both yeasts could survive relatively well at 3.5% NaCl concentration, and only C. utilis yeast could utilize zinc.

• Korean Journal of Microbiology
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• v.19 no.2
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• pp.63-77
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• 1981

The growth rate of yeast population (Saccharomyces uvarum) cultivated in the Knopp's modified medium (plus various carbon sources) appeared the highest value when the Knopp's minimal medium was treated to 1.5% with disaccharide such as maltose and sucrose. Also the treatment of lactose and raffinose resulted in polulation growth as to the population size in case of maltose and sucrose. However, the gorwth of yeast was not occurred at all when a polysaccharide, such as inulin, was added as carbon source. The growth from of yeast population in Knopp's modified medium are characterized by the fact that log phase continued 100hrs after inoculation and that stationary state phase appeared in general 250hrs after inoculation. Applying the various carbon sources to respiration substrate for yeast cell, the respiration rate of yeast showed the highest value in treatment of maltose and followed in order of raffinose, lactose, glucose, and sucrose. Determined the amount of poly-phosphate and turn over pathway of poly-phosphate according to culture phase of yeast, it is revealed that the yeast synthesized 3 types of poly phosphate (poly-P A,B, and C) and postulated that turn over pathway of poly-phosphate as follows ; Inorganic phosphate is converted into each kind of polyphosphates, and then one part of poly-P-C is converted into poly-P-B, the rest poly-p-C and poly-P-B are converted into poly-P-A. The synthesized poly-phosphate is considered to have a role as energy pool utilizing to synthesis of cellular organic materials. Of the 13 carbon sources used in this experiment, the useful carbon sources for biosynthesis of poly-phosphate and cellular organic materials are confirmed as disaccharide (maltose and sucrose) as well as glucose. Protein synthesis in yeast cell showed the two peaks on 6th and 8th day after inoculation ; nucleic acid on 2nd day (48hrs), carbohydrates on 2nd day (48hrs), and phospholipid on 2nd and 8th day after inoculation, respectively.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.2
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• pp.89-102
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• 2009

Objectives : The purpose of this study was evaluated hypoglycemic effect of culture broth of germanium-fortified Tricholoma matsutake mycelium and yeast. Methods : We examined $\alpha$-glucosidase inhibitory activity, blood glucose level, concentration of serum lipid, and serum metabolic variables of Tricholoma matsutake mycelium and yeast fortified Germanium. in streptozotocin induced diabetic rat. Results : In the $\alpha$-glucosidase inhibitory activity, germanium-fortified yeast was significantly higher than germanium-fortified Tricholoma matsutake mycelium. The hypoglycemic effects of germaniumfortified Tricholoma matsutake mycelium was higher than germanium-fortified yeast. The activity of alkaline phosphatase(ALP), aspartate aminotransferase(AST) and alanine aminotransferase(ALT) was significantly lower in the germanium-fortified Tricholoma matsutake mycelium and yeast than in diabetic control(DC) group and diabetic positive control(PC) group. The concentration of total cholesterol and triglyceride of germanium-fortified yeast was significantly lower than germanium-fortified Tricholoma matsutake mycelium, DC group and PC group. Conclusions : The results suggest that germanium-fortified Tricholoma matsutake mycelium and yeast have improvement effects in blood glucose, serum lipid and liver function.

• Food Engineering Progress
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• v.15 no.4
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• pp.413-419
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• 2011

For producing a high added-value natural seasoning ingredient, a yeast extract (Yx) was supplemented with a rice protein residue fermented with Bacillus licheniformis (Rfl) or with Bacillus subtilis (Rfs). A rice protein residue was obtained after enzymatic hydrolysis of rice protein which was used for preparing a yeast culture medium. Overall acceptabilities of the supplemented yeast extracts (YxRfl or YxRfs) were higher compared to pure yeast extract. Savory taste like umami was found to increase noticeably by adding a fermented rice protein residue to yeast extract, which was confirmed in taste sensor analysis and in sensory test. Beyond the presence of savory tasting amino acids such as Glu and Asp in a fermented rice protein residue, it is assumed that other soluble peptide fractions remained play an important role in enhancing taste of the supplemented yeast extracts. Thus, the yeast extract added with a fermented rice protein residue could be applied to manufacture a natural seasoning ingredient.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.219-226
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• 1976

To meet the need of protein feed and fine more efficient ways of returning waste to resources, we have carried out the study of the production of yeast for foods and feeds from the corn starch cake. The present study includes the method for acid-hydrolysis, the selection of yeast capable of utilizing hydrolyzate of the corn starch cake, and culture condition of Candida tropicalis under the liquid culture and the semisolid culture. Obtained results were as follows. 1. Hydrochloric acid was more excellent on the hydrolysis of the corn starch cake than sulfuric acid, and the yield of sugar was maximum, 57.2%, when the corn starch cake was hydrolyzed with 1.0% of hydrochloric acid at 2.0kg/cm for 30 minutes. 2. As the acid solution content was increased, more sugar was liberatedfrom the mixture, until the acid solution-substrate ratio reached 10:1. Beyond this point, no further increase was observed. To prepare the cultural medium of semisolid fermentation, a acid solution to substrate ratio of 3:1 appeared to be optimum. 3. Out of 6 yeast strains, Candida tropicalis had excellent growth on the hydrolyzate of the corn starch cake, and optimum temperature and initial pH were $30^{\circ}C$ and 6.0 respectively. 4. Optimum liquid medium of Candida tropicalis is ures 0.3%, potassium phosphate monobasic 0.15g and magnesium sulfate 0.04g in 100ml of the hydrolyzate of the corn starch cake, while optimum semisolid medium is ammonium chloride 0.4g, potassium phosphate monobasic 0.1%, magnesium sulfate 0.04%. 5. Candida tropicalis could assimilate the sugar in the hydrolyzate up to more than 88.75%, and a yield of dry yeast reached 19.13% to the corn starch cake under the liquid culture. 6. Compared to the that of the untreated corn starch cake, the cellulose content of the semisolid fermented cake decreased by 3.76% to 14.7%, whereas dry yeast contents increased by 13.89%.

• Korean Journal of Pharmacognosy
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• v.27 no.4
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• pp.289-294
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• 1996

In previous paper, we described the induced callus of Corydalis remota contains a significant amount of alkaloids. This study describes an optimal condition to maximize alkaloid production. The suspension cultures maintained alkaloid production ability after fifth subculture and a small amount of alkaloid seemed to be released out of cells. The yields of alkaloid by cultured cells was varied depending on the concentrations of NAA, carbon sources and phosphate ion and depending on the vitamin combinations and concentrations. Biosynthetic precursor and an elicitor treatment also affected the total alkaloid yield of the cultures. The optimal conditions for alkaloid production were as follows: 1) MS basal salt containing 30 g/l of glucose, 1.0 mg/l of NAA, and vitamins of LS medium should be used. 2) The culture should be treated with tyrosine 20 mg/l, and yeast extract 1.5 ml/l after the culture reached a stationary phase of growth. Five alkaloids were isolated from the cultures and they were characterized. The spectral data unambiguously revealed that the isolated compounds were dihydrosanguinarine, protopine. tetrahydropalmatine, allocyptopine and ambinine, respectively.

• Journal of the Korean Society of Food Culture
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• v.30 no.4
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• pp.475-480
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• 2015

Jeju citrus, which contains an abundance of calcium and vitamin, was used to develop fermented citrus peel extract. A total of seven probiotic strains were applied to tangerine dermis to select the best growing bacteria in citrus peel extracts. B. longum, B. bifidum, and L. mesenteroides were found to grow best in citrus peel extract culture containing glucose, yeast extracts, peptone, and potassium phosphate. Citrus peel extract culture consisting of 1% yeast extract, 5% peptone, and 0.1% phosphate was the best environment for growth of probiotics. The pH, acidity, and viable cell numbers of these fermented extracts were measured. The initial pH level of fermented extracts with nutrients was 5.25 and dropped rapidly to 3.39 after 72 hours of fermentation. The acidity of fermented extracts increased to 4.08 % after 72 hours of fermentation, and the viable cell number in fermented extracts after refrigeration for 2 weeks was $1.3{\times}10^{10}CFU/mL$. The antimicrobial activity of citrus peel fermented extracts against Campylobacter jejuni was determined, and concentrations more than 25,000 ppm showed antimicrobial activity.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.696-699
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• 1990

Some mixed culture systems consisting of koji molds and yeast were tested for the ethanol production by simultaneous saccharification and fermentation using polished rice as the substrate. Aspergillus shirousamii showed the highest ethanol production in the mixed culture with Saccharomyces cerevisiae on steamed rice added with 150 ml water in 250 ml Erlenmeyer flask. The optimum initial pH, temperature and specific surface for the ethanol production in this system were 6.5, $30^{\circ}C$, and 0.1, respectively. Under this condition, 12.9% ethanol was produced with inoculation with $5{\times}10^2$ conidia/ml of A. shirousamii and $5{\times}10^6\;cells/ml$ of S. cerevisiae in 10 days.