• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.585-591
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• 2014

To evaluate the potential utility of pretreatment of raw biomass with a complex microbial system, we investigated the degradation of rice straw by BMC-9, a lignocellulose decomposition strain obtained from a biogas slurry compost environment. The degradation characteristics and corresponding changes in the bacterial community were assessed. The results showed that rapid degradation occurred from day 0 to day 9, with a peak total biomass bacterium concentration of $3.3{\times}10^8$ copies/ml on day 1. The pH of the fermentation broth declined initially and then increased, and the mass of rice straw decreased steadily. The highest concentrations of volatile fatty acid contents (0.291 mg/l lactic acid, 0.31 mg/l formic acid, 1.93 mg/l acetic acid, and 0.73 mg/l propionic acid) as well as the highest xylanse activity (1.79 U/ml) and carboxymethyl cellulase activity (0.37 U/ml) occurred on day 9. The greatest diversity among the microbial community also occurred on day 9, with the presence of bacteria belonging to Clostridium sp., Bacillus sp., and Geobacillus sp. Together, our results indicate that BMC-9 has a strong ability to rapidly degrade the lignocelluloses of rice straw under relatively inexpensive conditions, and the optimum fermentation time is 9 days.

• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.667-674
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• 2014

Twenty-five Saccharomyces cerevisiae strains were screened for the highest sugar tolerance, ethanol-tolerance, ethanol production, and inhibitor resistance, and S. cerevisiae KL5 was selected as the best strain. Inhibitor cocktail (100%) was composed of 75 mM formic acid, 75 mM acetic acid, 30 mM furfural, 30 mM hydroxymethyl furfural (HMF), and 2.7 mM vanillin. The cells of strain KL5 were treated with ${\gamma}$-irradiation, and among the survivals, KL5-G2 with improved inhibitor resistance and the highest ethanol yield in the presence of inhibitor cocktail was selected. The KL5-G2 strain was adapted to inhibitor cocktail by sequential transfer of cultures to a minimal YNB medium containing increasing concentrations of inhibitor cocktail. After 10 times of adaptation, most of the isolated colonies could grow in YNB with 80% inhibitor cocktail, whereas the parental KL5 strain could not grow at all. Among the various adapted strains, the best strain (KL5-G2-A9) producing the highest ethanol yield in the presence of inhibitor cocktail was selected. In a complex YP medium containing 60% inhibitor cocktail and 5% glucose, the theoretical yield and productivity (at 48 h) of KL5-G2-A9 were 81.3% and 0.304 g/l/h, respectively, whereas those of KL5 were 20.8% and 0.072 g/l/h, respectively. KL5-G2-A9 reduced the concentrations of HMF, furfural, and vanillin in the medium in much faster rates than KL5.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1281-1287
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• 2015

This study was performed to determine the effect of field pea silages which were the organic acid (OA) alternative of oregano and cinnamon essential oils on fermentation quality and aerobic stability. Whole crop pea was harvested at full pod stage and wilted in the laboratory at the 48 h. The chopped pea was mixed and divided into equal portions allocated to five groups: CON (non-treated), distilled water, denoted as control group; OA group, a mixture of 60% formic acid, 20% sodium formate and 20% water applied at a rate of 5 g/kg fresh forage (Silofarm Liquid, Farmavet); origanum (ORE) group, Origanum onites essential oil at 400 mg/kg fresh forage; cinnamon (CIN) group, cinnamon essential oil at 400 mg/kg fresh forage; origanum+cinnamon (ORECIN) group, a mixture of ORE and CIN applied at an equal rate of 400 mg/kg fresh forage. Cinnamon decreased acetic acid (AA), ammonia nitrogen ($NH_3-N$) and weight loss (WL) at the end of 60 days silage. Crude protein (CP) and dry matter (DM) increased by cinnamon essential oil. Yeasts were not detected in any treatments, including the control, after 7 days of air exposure. The $CO_2$ amount decreased and the formation mold was inhibited in the aerobic period by the addition of cinnamon oil. Oregano did not show a similar effect, but when it was used with cinnamon, it showed synergic effect on AA and during aerobic period, it showed antagonistic effect on mold formation and DM losses. It was found in this study that cinnamon can be an alternative to organic acids.

• Applied Biological Chemistry
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• v.43 no.4
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• pp.253-259
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• 2000

In order to study the effects of the maturing temperature of kanjang(Korean traditional soy sauce) mash on the distributions of chemical compositions and sensory characteristics of kanjang, test kanjang mash prepared by mixing one part of meju and three parts of 20% salt solutions was matured at 15, 30 and $45^{\circ}C$ for 60 days respectively. It was found that although the higher the maturing temperature upto $45^{\circ}C$ for 60 days of maturing the higher total nitrogen, total free amino acids and pigment content in kanjang could be obtained, better quality kanjang containing the lower acetic acid, butyric acid and pyroglutamic acid with the higher ratio of the glutamic acid to the total free amino acids and the higher sensory evaluation scores could be prepared by maturing kanjang mash at $15^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1409-1418
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• 2017

Two typical microbial communities from Chinese rice wine fermentation collected in Yichang city and Suzhou city in China were investigated. Both communities could ferment glutinous rice to rice wine in 2 days. The sugar and ethanol contents were 198.67 and 14.47 mg/g, respectively, for rice wine from Yichang city, and 292.50 and 12.31 mg/g, respectively, for rice wine from Suzhou city. Acetic acid and lactic acid were the most abundant organic acids. Abundant fungi and bacteria were detected in both communities by high-throughput sequencing. Saccharomycopsis fibuligera and Rhizopus oryzae were the dominant fungi in rice wine from Suzhou city, compared with R. oryzae, Wickerhamomyces anomalus, Saccharomyces cerevisiae, Mucor indicus, and Rhizopus microsporus in rice wine from Yichang city. Bacterial diversity was greater than fungal diversity in both communities. Citrobacter was the most abundant genus. Furthermore, Exiguobacterium, Aeromonas, Acinetobacter, Pseudomonas, Enterobacter, Bacillus, and Lactococcus were highly abundant in both communities.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.397-402
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• 2006

The treatment characteristics of leachate produced from pretreatment facilities like composting and feeding were investigated in a mesophilic anaerobic treatment. Experiments were performed in two phase which were acidification and methane fermentation. The acidification step was optimized for OLR from 1 to $4.5kg\;COD/kg\;VS{\cdot}day$ without adding NaOH. As experiment dates became longer, the solubilization ratio of particles increased up to 30% over 70 days. TVA was generated up to maximum 9,970mg HAc/L at OLR of $2kg\;COD/kg\;VS{\cdot}day$. But TVA was generated to minimum 6,519mg HAc/L at OLR of $4.5kg\;COD/kg\;VS{\cdot}day$. The acidification ratio was analyzed from 10.9% to 3.8% at OLR of $2kg\;COD/kg\;VS{\cdot}day$ and $4.5kg\;COD/kg\;VS{\cdot}day$ respectively. After 55 days, salt contents in the acid fermenter were accumulated and stabilized at the concentration of 3,150mg/L. Sodium ion($Na^+$) concentration was stabilized at 1,300mg/L. At methane fermentation step, biogas was generated up to 750ml and 937.5ml at the feeding volume of 20ml and 25ml respectively for acid fermented liquid during 25 days. About 80% of total biogas was generated during early 15 days and 95% were generated during 18 days respectively. After 25 days of the BMP test, acetic acid was removed approximately 97% and 98%, in case of those two experimental conditions.

• KSBB Journal
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• v.18 no.2
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• pp.145-148
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• 2003

The hydrogen-producting bacterium was isolated from fresh water and identified as Enterbacter cloacae. The isolated was named Enterobacter cloacae YJ-1. In batch culture, The optimum cultivation temperature and pH of strain YJ-1 was 35$^{\circ}C$ and 7.5, respectively. All of the added glucose was consumed completely during fermentation even though pH was not controlled. Amount of hydrogen produced on each condition of 2% glucose, 4% sucrose and 5% fructose was 950, 1000 and 948 mL/L, respectively and resulted in increasing hydrogen production approximately 2.5-times more than controlled condition. The macimum hydrogen production was obtained when 50mM phosphate was added. was obtained when 50mM phosphate was added. In repeated0batch culture, yeast extract, but the production amount was not changed on the condition of over 0.5%, Most of the organic acides produced during the fermentation were formic and acetic acid, and propionic acid was moiety also generated.

• Korean journal of food and cookery science
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• v.7 no.2
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• pp.81-88
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• 1991

The changes of the contents of chemical components and sensory evaluation of kimchi which were prepared by addition of different amount of ginseng were investigated during fermentation 50 days at $4^{\circ}C$. The data analysis revealed followings; 1. While saltiness was maintained at around 2.3% level during the entire fermentation periods. Kimchi containing 2% and 4% ginseng showed higher pH, reducing sugar, hardness by Instron and lower acidity than kimchi without ginseng. 2. Results from analysis of organic acids contains by HPLC revealed that all three groups contained relatively high concentration of oxalic acid, lactic acid and malic acid. 3. A result of sensory evaluation revealed that kimchi containing 2% and 4% ginseng was higher in hardness, savory taste and carbonated taste, and lower in sour taste, moldy off flavor than kimchi without ginseng, thus scoring high in overall eating quality. Considering all results obtained throughout this experiments, it can be concluded that the addition of small amount of ginseng to kimchi improve overall acceptability and retard rancidity thus increasing the period during which kimchi is eatable.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.509-516
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• 2013

This study estimated the fermentation characteristics and nutrient value of corn-lablab bean mixture silages relative to corn silages. The effects of feeding corn-lablab bean mixture silages on nutrient apparent digestibility and milk production of dairy cows in northern China were also investigated. Three ruminally cannulated Holstein cows were used to determine the ruminal digestion kinetics and ruminal nutrient degradability of corn silage and corn-lablab bean mixture silages. Sixty lactating Holstein cows were randomly divided into two groups of 30 cows each. Two diets were formulated with a 59:41 forage: concentrate ratio. Corn silage and corn-lablab bean mixture silages constituted 39.3% of the forage in each diet, with Chinese wildrye hay constituting the remaining 60.7%. Corn-lablab bean mixture silages had higher lactic acid, acetic acid, dry matter (DM), crude protein (CP), ash, Ca, ether extract concentrations and ruminal nutrient degradability than monoculture corn silage (p<0.05). Neutral detergent fiber (NDF) and acid detergent fiber (ADF) concentrations of corn-lablab bean mixture silages were lower than those of corn silage (p<0.05). The digestibility of DM, CP, NDF, and ADF for cows fed corn-lablab bean mixture silages was higher than for those fed corn silage (p<0.05). Feeding corn-lablab bean mixture silages increased milk yield and milk protein of dairy cows when compared with feeding corn silage (p<0.05). The economic benefit for cow fed corn-lablab bean mixture silages was 8.43 yuan/day/cow higher than that for that fed corn silage. In conclusion, corn-lablab bean mixture improved the fermentation characteristics and nutrient value of silage compared with monoculture corn. In this study, feeding corn-lablab bean mixture silages increased milk yield, milk protein and nutrient apparent digestibility of dairy cows compared with corn silage in northern China.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.53-59
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• 1993

In situ degradability and fermentation characteristics in the rumen of goats fed whole crop corn forage ensiled with (MS silage) or without (CS silage) 30% of cage layer manure (CLM) were investigated. The two silages were well preserved. To adjust nitrogen intake of CS silage to that of MS silage, the 3rd group of goats was given urea with CS silage at feeding time (US silage). Each goat was given a diet of 2% of the body weight (dry matter basis) daily. In situ degradability of dry matter (DM) and crude protein (CP) of MS silage in the rumen were higher than those of CS and US silages. Total potentially degradable portions of DM and CP in MS silage were also higher than those in CS and US silages. Blood urea nitrogen and rumen ammonia nitrogen concentration of goats fed US and MS silages were significantly (p<0.05) higher than those of goats fed CS silage. Acetic, propionic and butyric acids in ruminal fluids of goats fed MS silage were significantly (p<0.05) higher than those of goats fed CS and US silages.