• Food Science of Animal Resources
• /
• v.34 no.6
• /
• pp.769-776
• /
• 2014

The goat placenta was fermented by Bacillus subtilis and the optimal fermentation parameters of strongest antioxidant capacity of peptides were obtained using response surface methodology (RSM). The effects of fermentation time, initial pH value and glucose content on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity of the goat peptides were well fitted to a quadric equation with high determination coefficients. According to the data analysis of design expert, the strongest DPPH radical scavenging capacity value was obtained with the following conditions: content of glucose was 2.23%, initial pH value was 7.00 and fermentation time was 32.15 h. The DPPH radical scavenging capacity commonly referring antioxidant activity showed a concentration dependency and increased with increasing peptide concentration. The effects of temperature and pH were assessed to determine the stability of antioxidant peptides prepared from goat placenta. Antioxidant peptides showed good stabilities when temperature was lower than $70^{\circ}C$. However, the antioxidant peptides lost antioxidant activities rapidly under alkaline and excessive acid condition. Ultrafiltration technique was performed to separate fermentation broth with different Mw (molecular weight). It was found that peptides in the range of < 3 KDa mainly accounted for the antioxidant activities.

• Journal of Microbiology and Biotechnology
• /
• v.10 no.6
• /
• pp.770-775
• /
• 2000

Several process parameters were studied to ascertain the effect on degradation of sugar cane bagasse in relation to the production of cellulase enzyme and reducing sugars by Solid Substrate Fermentation (SSF) and Submerged Culture Fermentation (SCF) of Aspergillus terreus SUK-1. The effect of air-flow rate (0-1.3 v/v/m), of different ratios of substrate weight to liquid volume (1:6, 1:10, 1:20, and 1:30 w/v, g/ml), scale-up effect (10, 20, and 100 times of 1:10 ration, w/v) and the effect of temperature (30, 40, 50, and $60^{\circ}C$) in SSF were studied. Air-flow rate of 1.0 v/v/m gave the highest enzyme activity (FPase 0.25 IU/ml, CMCase 1.24 IU/ml) and reducing sugars concentration (0.72 mg/ml). Experiment using 1:10 ratio (w/v) was found to support maximum cellulase activity (FPase 0.58 IU/ml, CMCase 1.97 IU/ml) and reducing sugar concentration (1.23 mg/ml). Scaling-up the ratio of 1:10(w/v) by a factor of 20 gave the highest cellulase activity (FPase 0.71 IU/ml, CMCase 2.25 IU/ml) and reducing sugar concentration (3.67 mg/ml). The optimum temperature for cellulase activity and reducing sugar production was $50^{\circ}C$(FPase 0.792 IU/ml, CMCase 2.25 IU/ml and 3.85 mg/ml for reducing sugar concentration). For SCF, the activity of cellulase enzyme and reducing sugar concentration was found to be lower than that obtained for SSF. The highest cellulase activity obtained in SCF was 50% lower than the highest cellulase activity in SSF, while for reducing sugar concentration, the highest concentration obtained in SCF was 90% lower than that obtained in SSF.

• Microbiology and Biotechnology Letters
• /
• v.24 no.5
• /
• pp.604-612
• /
• 1996

To improve the fermentation characteristics of the haploid starch-fermenting recombinant yeast strain K114/YIpMS$\Delta$R(LEU2/URA3) secreting both $\alpha$-amylase and glucoamylase was rare-mated with polyploid industrial yeast Saccharomyces sp. K35. The K35 strain had good fermentation-characteristics such as ethanol-tolerance, high temperature and sugar-tolerance, and high fermentation rate. Among the resulting 66 hybrids, the best strain RH51 was selected. The RH51 exhibited amylolytic activity of K114/YIpMS$\Delta$R(LEU2/URA3) as well as ethanol and sugar tolerance of K35. The optimum temperature of hybrid RH51 for starch fermentation was 34$\circ$C which was same as that of K35 but different from that (30$\circ$C) of K114/YIpMS$\Delta$R(LEU2/URA3). The optimum pH was 5.0. The optimum size of inoculum was 2% as the pellet (w/v) of yeast cells. The hybrid strain RH51 produced 7.0% ethanol (w/v) from 20% (w/v) soluble starch while K35 formed almost no ethanol, 0.3% (w/v). RH51 strain produced 7.5% (w/v) ethanol after 8 days in a 2.5 l fermenter containing 800 ml of 20% (w/v) soluble starch. The residual starch content in the fermentation medium was 1.68% (w/v), and therefore almost all the starch was fermented completely.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.8
• /
• pp.986-996
• /
• 2017

In this study, we optimized fermentation conditions for burdock vinegar by response surface methodology. We confirmed the fermentation characteristics and major components of burdock vinegar. Alcohol fermentation of burdock extract added with 15% apple concentrates for vinegar production was performed. Consequently, 6.4% alcohol was produced after 5 days of fermentation. Central composite design was applied to investigate the effects of two independent variables, fermentation time (5~17 days; X1) and fermentation temperature ($26{\sim}34^{\circ}C$; X2), on fermentation of burdock vinegar. Fermentation conditions were optimized using characteristics of fermentation broth as a dependent variable. Acetic acid contents of dependent variables were 3.85~4.73% during acetic acid fermentation. The correlation coefficient ($R^2$) of the derived equation from the response surface regression for acetic acid contents was 0.9850 with significance level of 1%. Arctiin contents of all fermentation samples were 0.37~0.50 mg/100 mL, with an $R^2$ value of 0.8380 and significance level of 5%. We elicited a regression equation for each variable and superimposed the optimum area of fermentation conditions for characteristics and effective constituent contents of the fermentation broth. The predicted values for the optimum fermentation conditions for burdock vinegar were at $31^{\circ}C$ and 16 days.

• Korean Journal of Food Science and Technology
• /
• v.20 no.6
• /
• pp.883-889
• /
• 1988

The salted small shrimps(Acetes japonicus) were fermented for 3 months at room temperature. During the period of fermentation, the changes of shrimp protein properties were determined. The extractability of soluble protein was slightly decreased in 1 month fermentation, but thereafter increased. The contents of 10% TCA soluble fraction were gradually increased during 3 month fermentation, and the rate of 10% TCA soluble fraction/total soluble protein was also greatly increased during the period of fermentation. Sephadex G-100 gel filtration pattern was changed after 1 month fermentation, showing the disappearance of low molecular weight protein peaks, the decomposition and the delay of elution time of main shrimp protein peaks. Polyacrylamide gel disc electrophoresis patterns showed the degradation of main protein bands into lots of smaller bands after 1 month fermentation. The contents of total free amino acids were slightly decreased in 1 month fermentation and then gradually increased during the Period of fermentation. The rate of free amino acids/soluble protein was steadily increased during the period of fermentation, but the rate of free amino acids/10% TCA soluble fraction was decreased continually during the period of fermentation. The contents of most free amino acids were increased during the period of fermentation, but those of histidine and arginine were greatly decreased in 1 month fermentation. Ammonia was increased after 1 month fermentation. The pH value of salted shrimp was slowly changed during 3 months of fermentation, showing increase from 7.8 to 8.2.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.12
• /
• pp.1654-1659
• /
• 2008

The aim of this study was to compare the fermentation characteristics of tissue cultured mountain ginseng, extruded tissue cultured mountain ginseng, and root hair of red ginseng. Also, pH, acidity, brix, reducing sugar, total sugar, and alcohol were analyzed. The extrusion conditions were barrel temperature of 110 and $140^{\circ}C$ and moisture content of 25 and 35%. Fermentation temperature was $27^{\circ}C$ for 15 days and the cultivation was fixed with Saccharomyces cerevisiae, Aspergillus usamii, and Rhizopus japonicus. The results showed that pH, brix, reducing sugar content, and total sugar content of fermented broths were decreased after 5 days and then maintained steadily for the following 10 days. Acidity of final fermented broths were 1.12% (root hair of red ginseng), 1.19% (tissue cultured mountain ginseng), and $0.97{\sim}1.02%$ (extruded tissue cultured mountain ginseng), respectively. Alcohol content of final fermented broths were 3.82% (root hair of red ginseng), 0.91% (tissue cultured mountain ginseng), and $1.86{\sim}2.18%$ (extruded tissue cultured mountain ginseng). The fermentation efficiency of extruded tissue cultured mountain ginseng (barrel temperature $140^{\circ}C$, moisture content 25%) were the highest. In conclusion, the fermentation efficiency was increased by extrusion process.

• Applied Biological Chemistry
• /
• v.27 no.4
• /
• pp.217-224
• /
• 1984

Effect of a thermophilic yeast (strain T-71) on the ethanol fermentation of raw starchy materials was investigated. The maximum temperature of the thermophilic yeast for the growing and fermentation was a little higher than that of ordinary yeasts and their resistance to ethanol was also high. Even though the optimum temperature of the thermophilic yeast for fermenting ethanol of several raw starchy materials was different depending upon the concentration of mashing, their optimum fermentation temperature was higher than the ordinary yeasts in all cases studied, and their fermentation efficiency was good enough to use. It was also found from the study that the period of fermentation could be shortened for about one to two days by using the thermophilic yeast.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.12
• /
• pp.1654-1663
• /
• 2013

Rice straw is closely associated with meju fermentation and it is generally known that the rice straw provides meju with many kinds of microorganisms. In order to elucidate the origin of meju fungi, the fungal diversity of rice straw was examined. Rice straw was collected from 12 Jang factories where meju are produced, and were incubated under nine different conditions by altering the media (MEA, DRBC, and DG18), and temperature ($15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$). In total, 937 strains were isolated and identified as belonging to 39 genera and 103 species. Among these, Aspergillus, Cladosporium, Eurotium, Fusarium, and Penicillium were the dominant genera. Fusarium asiaticum (56.3%), Cladosporium cladosporioides (48.6%), Aspergillus tubingensis (37.5%), A. oryzae (31.9%), Eurotium repens (27.1%), and E. chevalieri (25.0%) were frequently isolated from the rice straw obtained from many factories. Twelve genera and 40 species of fungi that were isolated in the rice straw in this study were also isolated from meju. Specifically, A. oryzae, C. cladosporioides, E. chevalieri, E. repens, F. asiaticum, and Penicillium polonicum (11.8%), which are abundant species in meju, were also isolated frequently from rice straw. C. cladosporioides, F. asiaticum, and P. polonicum, which are abundant in the low temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $15^{\circ}C$ and $25^{\circ}C$, whereas A. oryzae, E. repens, and E. chevalieri, which are abundant in the high temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $25^{\circ}C$ and $35^{\circ}C$. This suggests that the mycobiota of rice straw has a large influence in the mycobiota of meju. The influence of fungi on the rice straw as feed and silage for livestock, and as plant pathogens for rice, are discussed as well.

• Korean journal of food and cookery science
• /
• v.13 no.3
• /
• pp.364-368
• /
• 1997

The vitamin C contents in Mulkimchi (watery kimchi prepared with Yulmoo, leaf radish) were analyzed during its fermentation and storage at 30$^{\circ}C$, 15$^{\circ}C$ and 4$^{\circ}C$, respectively. The total amount of vit. C in Mulkimchi fermented for 1 day at 30$^{\circ}C$ was rapidly increased to the highest level of 20 mg％. At this time, Mulkimchi showed pH 4.5 and 0.2% of total acidity expressed in lactic acid. The total microbes of the kimchi amounted to 10$\^$8/ cfu/$m\ell$ which are mostly found to be lactic acid bacteria. However, the amount of vitamin C in Mulkimchi was decreased gradually during the storage at 30$^{\circ}C$, 15$^{\circ}C$ and 4$^{\circ}C$ for 9 days. In the Mulkimchi fermentated at 15$^{\circ}C$, the maximum amount of vitamin C was 15 mg％ at 4 to 5 day-fermentation. The pH of this kimchi was 4.0 and its acidity was 0.15% as lactic acid. When the storage temperature was dropped to 4$^{\circ}C$ after 1 day-fermentation at 15$^{\circ}C$, its vitamin C didn't reach the above level after 9 day storage. As the fermentation temperature was kept at 4$^{\circ}C$, the content of vitamin C in Mulkimchi remained at 10 mg％ of its initial storage and didn't change through the 9 days storage.

• Journal of Korea Foresty Energy
• /
• v.24 no.2
• /
• pp.1-9
• /
• 2005

After manufacturing fermentation system for degrading pig manure using environmentally friendly technique, performance of the system and characteristics of wood chips and pig manure fermented in the system were analyzed. Results from this study shows that proper fermentation temperature($55{\sim}60^{\circ}C$) reached 3days after the system started and degradation rate, which expresses fermentation performance of system, was $180{\iota}$/day. Even as progressing the fermentation of wood chips and pig manure mixture, the amount of extractives drawn out by alkali, and alcohol-benzene and lignin content was not varied. However, ash content in wood was increased. The inorganic compounds in pig manure seem to be transferred into wood chip. On the other hand holocellulose contents in wood were decreased a little. Holocellulose seems to be consumed as the second carbon source in fermentation process. Results through analysis of inorganic- and heavy metal elements contents in wood chips and pig manure fermented in long term process shows that inorganic elements($Ca^{2+},\;Mg^{2+},\;K^+,\;Na^+$ etc.) contents were increased with fermentation time and heavy metal elements(Cd, As, Cu etc.) which cause environmental pollution were not detected. Number of microorganisms including bacteria, actinomycetes, and fungi, the number of C.F.U(Colony Forming Unit) was increased while temperature in fermentation system was abruptly increased.