• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.61-68
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• 1975

This study was conducted (1) to isolate the film-forming yeast from the commercially available soy sauce, (2) to identify the state of soy sauce fermentation by the use of yeasts, (3) to confirm characteristics of yeasts. The result were as follows. 1. These yeast strains in the soy sauce fermentation test showed full fermentation of whole sugar content, reduction of the pure extract and relative reduction in total nitrogen. Soy sauce color was somehow faded to lower the stability of soy sauce. 2. In anti-fungal activity test butylparaben at a higher level 60 ppm., sodium propionate 2,400 ppm, sodium benzoate 800 ppm., menadion 165 ppm, showed their anti-fungal effect, while alcohol did not show the effect in the 3% additive group. 3. The optimum sodium chloride concentration for these strains in the 2% G.Y.P. medium was 5% and optimum temperature was $30^{\circ}C$. The extinction temperature was $62^{\circ}C$ for strain No-1 and No-3, and was $65^{\circ}C$ for No-2 and No-4. 4. The film-forming soy sauce turned out in the gas chromatogram to possess much flavor of low boiling point as compared with the standard. These flavors were considered due to flavor spoilage of the soy sauce. 5. These isolated yeasts were identified Saccharomyces rouxii (film-forming yeast) in the Lodder's taxanomic study.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.32-39
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• 2018

Samples of Laru (a fermentation starter) obtained from the upper part of Borneo Island were analyzed for their lactic acid bacteria (LAB) and fungal diversity using both a culture-independent method (PCR-DGGE) and culture-dependent methods (SDS-PAGE and MALDI-TOF MS). Pediococcus pentosaceus, Lactobacillus brevis, Saccharomycopsis fibuligera, Hyphopichia burtonii, and Kodamaea ohmeri were detected by all three methods. In addition, Weissella cibaria, Weissella paramesenteroides, Leuconostoc citreum, Leuconostoc mesenteroides, Lactococcus lactis, Rhizopus oryzae/Amylomyces rouxii, Mucor indicus, and Candida intermedia were detected by PCR-DGGE. In contrast, Lactobacillus fermentum, Lactobacillus plantarum, Pichia anomala, Candida parapsilosis, and Candida orthopsilosis were detected only by the culture-dependent methods. Our results indicate that the culture-independent method can be used to determine whether multiple laru samples originated from the same manufacturing region; however, using the culture-independent and the two culture-dependent approaches in combination provides a more comprehensive overview of the laru microbiota.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.250-255
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• 2001

Effect of molding temperature on the quality changes of extruded meju was studied. Meju was molded at 8$0^{\circ}C$, 6$0^{\circ}C$ and 4$0^{\circ}C$, and then stored at $25^{\circ}C$ with 50% of relative humidity for 30 days. The texture of the cooked soybean grain showed that the firmness and cohesiveness were increased, and consistency was decreased by decrease of molding temperature. The density of the meju molded at 8$0^{\circ}C$, 6$0^{\circ}C$ and 4$0^{\circ}C$ were 1.072g/mL, 1.079g/mL and 1.203g/mL, respectively. The meju molded at 4$0^{\circ}C$ had significantly higher density than those molded at 8$0^{\circ}C$ or 6$0^{\circ}C$. Also, delay of water evaporation, acidification, and rapid growth of fungal mycellium were observed on the sample with molding temperature at 4$0^{\circ}C$ during fermentation. Activity of amylase and protease, contents of total reducing sugar and amino nitrogen of 4$0^{\circ}C$-molded meju were represented lower level than those of 6$0^{\circ}C$ or 8$0^{\circ}C$-molded sample. Therefore, it was considered that the molding temperature was an important factor for meju fermentation and molding temperature of 6$0^{\circ}C$ or over would be acceptable.

• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.926-933
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• 2023

Aspergillus oryzae KCCM 11372 was used to enhance the production of β-glucan using humidity control strategies. Under conditions of 60% humidity, solid-state fermentation (SSF) increased the yields of enzymes (amylase and protease), fungal biomass (ergosterol), and β-glucan. The maximum concentrations obtained were 14800.58 U/g at 72 h, 1068.14 U/g at 120 h, 1.42 mg/g at 72 h, and 12.0% (w/w) at 72 h, respectively. Moreover, the β-glucan containing fermented brown rice (β-glucan-FBR) extracts at concentrations of 25-300 ㎍/ml was considered noncytotoxic to 3T3-L1 preadipocytes. We then studied the inhibitory effects of the extracts on fat droplet formation in 3T3-L1 cells. As a result, 300 ㎍/ml of β-glucan-FBR extracts showed a high inhibition of 38.88% in lipid accumulation. Further, these extracts inhibited adipogenesis in the 3T3-L1 adipocytes by decreasing the expression of C/EBPα, PPARγ, aP2, and GLUT4 genes.

• Korean Journal of Agricultural Science
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• v.29 no.2
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• pp.20-34
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• 2002

This study was conducted to examine the effects of an Aspergillus oryzae fermentation culture on the in vitro digestibilities of dry matter, crude fiber, acid detergent fiber (ADF), neutral detergent fiber (NDF), crude protein, and pH in in vitro experiment of diets for dairy cows. A fungal species, Aspergillus oryzae was supplied by Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea (KCTC 1229). The experimental diets were commercial compound feed (concentrate) and total mixed ration (TMR) for lactating cows, of which chemical analyses were determined at Research and Development Institute, Woosung Feed Co., Ltd., while the digestibilities were done at the laboratory of Chungnam National University. Aspergillus oryzae culture products were added to compound feed and TMR at the rate of 0, 1.0, 2.0, 3.0% respectively. The experimental diet with the rumen fluid sampled from Holstein fresian milking cows were used and digested for 24 hrs, 48hrs and 72hrs in the shaking incubator. The residues of the digesta were digested for 48hrs in the incubator in which put 30ml of 0.1N HCl with 0.2% pepsin at $39^{\circ}C$. The final precipitates were dried for 48hrs in the drier at $60^{\circ}C$. These experimental procedures were triplicated to determine the in vitro digestibility of dry matter, crude fiber, ADF, NDF, crude protein and pH. Compared to control diet, not added Aspergillus oryzae, the DM digestibility of fungal diets were improved 2.1%(63.1%), 9.7%(68.5%) and 9.0%(68.0%) for 24 hour fermentation in compound feed while 4.8%(60.0%), 6.4%(61.1%) and 2.9%(58.8%) in TMR. On the contrary, for 48 hour and 72 hour digestibilities, the effects of Aspergillus oryzae culture on the digestibility of dry matter were relatively lowered compared to 24 hour digestibility. Referring to the digestibility of dietary fiber, Aspergillus oryzae was believed to significantly improve digestibilities of crude fiber, ADF and NDF. Those were increased up to 13.3%(53.3%) for 24 hour fermentation, while 2.4%(54.6%) for 3.0% added for 72 hour fermentation in compound feed. However, there were no significant differences among the treatments for the inclusion rate of Aspergillus oryzae, even though the more inclusion rate, the better digestibility. The protein digestibilities were significantly improved from 0.4%(79.7%) to 9.4%(71.8%) by adding Aspergillus oryzae into compound feed. However, there were no significant differences between the two experimental diets, 2.0% and 3.0% Aspergillus oryzae included diets. In case of TMR, the protein digestibilities were significantly improved from 4.0%(70.4%) to 6.3%(65.1%) by adding Aspergillus oryzae. However, there were no significant differences between the two experimental diets, 2.0% and 3.0% Aspergillus oryzae included diets. In this study, there were no significant differences among the treatments in pH. On the contrary, there were slightly decrease in pH by adding Aspergillus oryzae into experimental diets but not significant. Summarizing the results of this examination, Aspergillus oryzae fermentation culture is believed to improve the digestibilities of dry matter, fiber and crude protein in cattle diets. However, more detailed research for the mechanism of the fungal culture is required to improve ruminal environment.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.259-269
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• 2019

Brown spot and sheath rot of rice are caused by fungal pathogens such as Curvularia lunata, Cochliobolus miyabeanus, and Sarocladium oryzae, and cause losses such as reduced rice yield and quality, which is an enormous problem with serious long-term effects. To search biological control agents of phytopathogenic fungi, five kinds of useful Bacillus-like isolates which are excellent in extracellular enzyme activity and produce siderophore were selected from paddy soil of Sunchang in Korea. The selected isolates were tested for excellent antifungal activity against three of the phytopathogenic fungi that frequently occur in rice, and JSRB 177 strain had the most excellent antifungal activity. Based on the experimental results, JSRB 177 is finally selected as a candidate for biological control and identified to Bacillus subtilis through 16S rRNA sequence analysis. In addition, physiological characteristics of JSRB 177 confirmed by analysis of carbohydrate fermentation patterns and enzyme production ability. Based on the above results, JSRB 177 is expected to be used as a biological control agent for the rice pathogenic fungi. In the future, further studies related to industrialization such as port test and establishment of mass production process are needed.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1400-1410
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• 2004

Eight crossbred (75% Holstein Friesian) cows in mid-lactation were randomly assigned to a switchback design with a 2x2 factorial arrangement to evaluate two nonstructural carbohydrate (NSC) sources (corn meal and cassava chips) with different rumen degradability and used at two levels of NSC (55 vs. 75%) with protein source (supplied by urea in the concentrate mix). The treatments were 1) Low degradable low level of corn (55%) 2) Low degradable high level of corn (75%) 3) High degradable low level of cassava (55%) and 4) High degradable high level of cassava (75%). The cows were offered the treatment concentrate at a ratio to milk yield at 1:2. Urea-treated rice straw was offered ad libitum as the roughage and supplement with 1 kg/hd/d cassava hay. The results revealed that total DM intake, BW and digestion coefficients of DM were not affected by either level or source of energy. Rumen fermentation parameters; NH3-N, blood urea nitrogen and milk urea nitrogen were unaffected by source of energy, but were dramatically increased by level of NSC. Rumen microorganism populations were not affected (p>0.05) by source of energy, but fungal zoospores were greater for cassava-based concentrate than corn-based concentrate. Milk production and milk composition were not affected significantly by diets containing either source or level of NSC, however concentrate than corn-based concentrate averaging (4.4 and 4.2, respectively). Likewise, income over feed, as estimated from 3.5% FCM, was higher on cassava-based concentrate than corn-based concentrate averaging (54.0 and 51.4 US$/mo, respectively). These results indicate that feeding diets containing either cassava-based diets and/or a higher of oncentrates up to 75% of DM with NPN (supplied by urea up to 4.5% of DM) can be used in dairy rations without altering rumen ecology or animal performance compared with corn-based concentrate.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1557-1565
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• 2016

Itaconic acid (IA) is a dicarboxylic acid included in the US Department of Energy's (DOE) 2004 list of the most promising chemical platforms derived from sugars. IA is produced industrially using liquid-state fermentation (LSF) by Aspergillus terreus with glucose as the carbon source. To utilize IA production in renewable resource-based biorefinery, the present study investigated the use of lignocellulosic biomass as a carbon source for LSF. We also investigated the production of fumaric acid (FA), which is also on the DOE's list. FA is a primary metabolite, whereas IA is a secondary metabolite and requires the enzyme cis-aconitate decarboxylase for its production. Two lignocellulosic biomasses (wheat bran and corn cobs) were tested for fungal fermentation. Liquid hydrolysates obtained after acid or enzymatic treatment were used in LSF. We show that each treatment resulted in different concentrations of sugars, metals, or inhibitors. Furthermore, different acid yields (IA and FA) were obtained depending on which of the four Aspergillus strains tested were employed. The maximum FA yield was obtained when A. terreus was used for LSF of corn cob hydrolysate (1.9% total glucose); whereas an IA yield of 0.14% was obtained by LSF of corn cob hydrolysates by A. oryzae.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.253-257
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• 2002

The time-dependent changes of red pigments production in solid-state plant scale fermentor using barley cultured with Monascus sp., instead of rice which was traditionally used, were investigated in this study. A steady increase in the yield of red pigments in barley occurred between the 3rd and 6th days. The optimized conditions (inoculation volume = 6∼8%, initial pH = 6, air supply = 0.6∼0.8 m) promoted the production of red pigments. Short-time steaming of barley (< 20 min) decreased fungal growth and pigments production due to the insufficient gelatiniza-tion. The optical density of the red pigments under the optimized conditions was 120 at 500 ]nm per gram of barley. In addition, the metabolites from the fermented barley with Monucus sp. showed antibacterial effects against Escherichia coli and Salmonella typhimurium. Barley was shown to be one of the best grain sources for solid-state fermentation with Monascu sp., fur obtaining natural pigments and also functional food materials.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1494-1500
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• 2012

Fermentation with filamentous fungi in a bioreactor is a complex dynamic process that is affected by flow conditions and the evolution of the rheological properties of the medium. These properties are mainly affected by the biomass concentration and the morphology of the fungus. In this work, the rheological properties of a fermentation with the fungus Beauveria bassiana under different hydrodynamic conditions were studied and the rheological behavior of this broth was simulated through a mixture of carboxymethyl cellulose sodium and cellulose fibers (CMCNa-SF). The bioreactor was a 10 L CSTR tank operated at different stir velocities. Rheological results were similar at 100 and 300 rpm for both systems. However, there was a significant increase in the viscosity accompanied by a change in the consistence index, calculated according to the power law model, for both systems at 800 rpm. The systems exhibited shear-thinning behavior at all stir velocities, which was determined with the power law model. The mixing time was observed to increase as the cellulose content in the system increased and, consequently, the efficiency of mixing diminished. These results are thought to be due to the rheological and morphological similarities of the two fungal systems. These results will help in the optimization of scale-up production of these fungi.