• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.313-320
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• 2014

Black liquor (BL) is a by-product of rice straw pulping process. It is a low costs raw material for production value-adding proteins and enzymes, which has been paid more and more attention to reduce its environmental pollution. Mixed cultures of micelial fungi, Trichoderma reesei Northern Regional Research Laboratory (NRRL)11236, Trichoderma reesei NRRL 6165 and Aspergillus niger strains NRC 5A, NRC 7A, and NRC 9A were evaluated for their ability to produce xylanase using crude hemicellulose (CHC) prepared from BL and peat moss as an inert support under solid state fermentation (SSF). The most potent strains, A. niger NRC 9A (818.26 U/g CHC) and T. reesei NRRL 6165 ($100.9{\pm}57.14$ U/g CHC), were used in a mixed culture to enhance xylanase production by co-culturing under SSF. In the mixed culture, xylanase production ($1070.52{\pm}12.57$ U/g CHC) was nearly1.3 and 10.6-fold increases over the activities attained in their monocultures, A. niger NRC 9A and T. reesei NRRL 6165, respectively. Optimization of the culture parameters of the mixed culture SSF process, concentration of ammonium sulfate and corn steep liquor, CHC/peat moss ratio, inoculum size and ratios of the two strains, initial pH value, initial moisture content and incubation time, exhibited a significant increase ($2414.98{\pm}84.02$ U/g CHC) in xylanase production than before optimization.

• Mycobiology
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• v.30 no.3
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• pp.166-169
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• 2002

Protein productivity by the cellulolytic fungi, Trichoderma viride(MTCC 800), Chaetomium globosum and Aspergillus terreus was compared in co-culture and mixed culture fermentations of cashewnut bran. Co-cultures were more effective in substrate saccharification, which ranged between $85{\sim}88%$ compared to the $62{\sim}67%$ saccharification shown by the monocultures. Maximum saccharification was induced by T. viride and C. globosum co-culture resulting in the highest 34% release of reducing sugars. The maximum 16.4% biomass protein and the highest protein productivity(0.58%) were shown by T. viride and A. terreus co-culture. A. terreus performed better in co-culture in the presence of T. viride rather than with C. globosum. Among the cellulolytic enzymes, FPase(Filter Paper Cellulase) activity was significantly higher in all the co-cultures and in the mixed culture than in their respective monocultures. Mixed culture fermentation involving all the three fungi was not effective in increasing the per cent saccharification or the biomass protein content over the co-cultures.

• Journal of Soil and Groundwater Environment
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• v.15 no.6
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• pp.114-121
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• 2010

Oxygen sensitivity and substrate requirement have been known as possible reasons for the intricate growth of Dehalococcoides spp. and limiting factors of for routinely applying bioaugmentation using anaerobic Dehalococcoides-containing microbes for remediating chlorinated organic compounds. To explore the effect of the short-term exposure of the short-term exposure of oxygen on Dehalococcoides capability, dechlorination performance, and hydrogen production fermentation from formate, an anaerobic reductive dechlorination mixed-culture (Evanite culture) including dehalococcoides spp. was in this study. In the results, once the mixed-culture were exposed to oxygen, trichloroethylene (TCE) degradation rate decreased and it was not fully recovered even addition of excess formate for 40 days. In contrast, hydrogen was continuously produced by hydrogen-fermentation process even under oxygen presence. The results indicate that although the oxygen-exposed cells cannot completely dechlorinate TCE to ethylene (ETH), hydrogen fermentation process was not affected by oxygen presence. These results suggest that dechlorinating microbes may more sensitive to oxygen than fermenting microbes, and monitoring dechlorinators activity may be critical to achieve an successful remediation of a TCE contaminated-aquifer through bioaugmentation using Dehalococcoides spp..

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.686-690
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• 1989

Non sticky short grain rice was liquidized by ${\alpha}-amylase$ from Bacillus species after cooking 20min at $121^{\circ}C$ and a lactic acid bacteria fermentation proceeded. The product using mixed culture of S. thermophilus, L. bulgaricus and L. plantarum was superior than the one of any single or mixed culture. The most acceptable pH of it was 3.70. It is suggested that L. plantarum is more deeply related to the product quality. Skim milk promoted lactic acid fermentation but the quality of the final product was not acceptable in the result of sensory evaluation. The acceptable dilution rate of final product was 1:3 (rice: water) by weight.

• Microbiology and Biotechnology Letters
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• v.27 no.1
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• pp.46-53
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• 1999

The purpose of this study was to optimize the conditions of continuous mixed culture of C.butyricum and R. spaeroides K-7, which were able to produce hydrogen using biomass-dreived substrate. To investigate the possibility of continuous culture, semi-continuous culture was carried out for 20 days. In semi-continuous culture using the reactor system, the replacement rate of fresh medium was 30% of total medium volume for the highest hydrogen evolution. In continuous culture, the optimum dilution rate was determined to be 0.05$h^{-1}$. The continuous culture produced 3.1 times as compared with the hydrogen on batch culture. On the other hand, the continuous mixed culture produced 1.3~2.1 times as much as hydrogen of the continuous monoculture of C. butyricum. When 10g of glucose in the media (1l) was supplied as a carbon source on continuous culture, mixed culture of C. butyricum and R. sphaeroides K-7 increased hydrogen evolution rate. Because considerable amount of glutamate was contained in waste water of glutamate fermentation, utilization of glutamate was examined in mixed culture. As a result of examination, production of hydorgen was slightly inhibited by high concentration of glutamate, more than 20mM, on continuous monoculture of R. sphaeroides K-7. On the other hand, both on continuous monoculture of C. butyricum and on mixed culture of C. butyricum and R. sphaeroides K-7, production of hydrogen was not inhibited by high concentration of glutamate such as 100mM. Hence this suggests that high concentration of waste water can be used as good substrate for hydrogen production on monoculture of C. butyricum and mixed culture of C. butyricum and R. sphaeroides K-7.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.700-703
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• 2001

The influence of process conditions on highly branched glucooligosaccharides production by mixed culture of Leuconostoc mesenteroides ATCC 13146 and Lipomyces starkeyi ATCC 74054 was studied. We divided the batch culture fermentations into two groups according to inoculation method. One-point inoculation was performed by coinoculation of L. mesenteroides and L. starkeyi at the ration of 10 to 1, and two-point inoculation by L. mesenteroides inoculation first and L. starkeyi inoculation after L. mesenteroides grew to the end of the log phase of growth. Two-point inoculation improved the yield of oligosaccharide by 1.5 to 20 fold more than one-point inoculation. In this process, the highest yield of oligosaccharides (48% of theoretical yield) and productivity (0.85 g/l/h) were obtained with starch as an initial substrate for L. starkeyi growth. The estimated composition of the end product consisted of 31.5% oligosaccharides, 17.6% dextran, and 46.5% mannitol.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.533-538
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• 1989

The enhanced growth and lactic fermentation of L. acidophilus, when mixed with S. uvarum, was investigated. Spent medium of S. uvarum, at 10%, stimulated the growth and lactic fermentation of L. acidophilus, and also increased the content of monosaccharide while decreased the contents of sucrose, raffinose, and stachyose in soymilk. While single culture of L. acidophilus consumed only the monosaccharides in soymilk, the mixed culture of L. acidophilus and S. uvarum consumed almost all the oligosaccharides as well as the monosaccharides in soymilk. Thus it was assumed that S. uvarum converted the oligosaccharides into monosaccharides so that L. acidophilus can produce more lactic acid and cell mass by using the increased monosaccharides.

• Journal of the Korean Society of Food Culture
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• v.26 no.2
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• pp.190-197
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• 2011

Chungtaejeon is a traditional tea introduced in the age of the Three States and is the only "Don-cha" culture in the world that survived on the southwestern shore of Korea. To restore Chungtaejeon and to make the tea with consistent quality, the microorganisms involved in traditional type fermentation of Chungtaejeon were isolated, and the tea was prepared with high fermentation ability starters. The sensuous characteristics of Chungtaejeon were also examined. Only Bacilli were found in 3 and 5 year aged Chungtaejeon samples. The Lactobacilli were isolated from properly fermented kimchi and one of them showed high growth capability in media containing green tea extract and also showed strong antagonistic activity against methicillin-resistant Staphylococcus aureus, S. aureus, Salmonella, and E. coli. It was identified and named Lactobacillus plantarum CHO25. Chungtaejeon was fermented with a single starter of L. plantarum CHO25 and with a mixed starter (L. plantarum CHO25, Saccharomyces cerevisiae and Bacillus amyloliquefaciens CHO104). The single fermented sample had the highest cell growth after 5 days of inoculation and the level decreased slowly thereafter. The mixed fermented sample showed strong growth of S. cerevisiae. The highest hunter values were the a value of the single fermented sample and the b value of the mixed sample. The single fermented tea showed the best incense score.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.4
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• pp.275-287
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• 2000

Fermentation strategies for recombinant protein production in Pichia pastoris have been investigated and are reviewed here. Characteristics of the expression system, such as phenotypes and carbon utilization, are summarized. Recently reported results such as growth model establishment, app58lication of a methanol sensor, optimization of substrate feeding strategy, DOstat controller design, mixed feed technology, and perfusion and continuous culture are discussed in detail.

• Journal of Animal Science and Technology
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• v.62 no.2
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• pp.227-238
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• 2020

Use of raw feedstuffs for livestock is limited by low digestibility. Recently, fermentation of feedstuffs has been highlighted as a new way to improve nutrient absorption through the production of organic acids using inoculated microorganisms, which can also play a probiotic role. However, standard procedures for feedstuff fermentation have not been clearly defined because the process is influenced by climatic variation, and an analytical standard for fermented feedstuffs is lacking. This study aimed to evaluate the microbiological and biochemical changes of feedstuffs during fermentation at temperatures corresponding to different seasons (10℃, 20℃, 30℃, and 40℃). We also investigated the effects of yeast, lactic acid bacteria (LAB), and Bacillus spp. on fermentation and determined the results of their interactions during fermentation. The viable cells were observed within 8 days in single-strain fermentation. However, when feedstuffs were inoculated with a culture of mixed strains, LAB were predominant at low temperatures (10℃ and 20℃), while Bacillus spp. was predominant at high temperatures (30℃ and 40℃). A significant drop in pH from 6.5 to 4.3 was observed when LAB was the dominant strain in the culture, which correlated with the concentrations of lactic acid. Slight ethanol production was detected above 20℃ regardless of the incubation temperature, suggesting active metabolism of yeast, despite this organism making up a marginal portion of the microbes in the mixed culture. These results suggested that fermentation temperature significantly affects microbiological profiles and biochemical parameters, such as pH and the lactic acid concentration, of fermented feedstuffs. Our data provide valuable information for the determination of industrial standards for fermented feedstuffs.