• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.383-390
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• 2010

A newly isolated active producer of raw-starch-digesting amyloytic enzymes, Rhizopus microsporus var. chinensis CICIM-CU F0088, was screened and identified by morphological characteristics and molecular phylogenetic analyses. This fungus was isolated from the soil of Chinese glue pudding mill, and produced high levels of amylolytic activity under solid-state fermentation with supplementation of starch and wheat bran. Results of thin-layer chromatography showed there are two kinds of amyloytic enzymes formed by this strain, including one $\alpha$-amylase and two glucoamylases. It was found in the electron microscope experiments that the two glucoamylases can digest raw corn starch and have an optimal temperature of $70^{\circ}C$. These results signified that amyloytic enzymes secreted by strain Rhizopus microsporus var. chinensis CICIM-CU F0088 were types of thermostable amyloytic enzymes and able to digest raw corn starch.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.487-496
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• 2021

Microalgae is one of the promising biodiesel feedstock with high growth rates compared to those of terrestrial oil crops. Despite its numerous advantages, biodiesel production from microalgae needs to reduce energy demand and material costs further to go to commercialization. During solvent extraction of microalgal lipids, lipid-extracted algae (LEA) cell residue is generated as an organic solid waste, about 80-85% of original algal biomass, and requires an appropriate recycling or economic disposal. The resulting LEA still contains significant amount of carbohydrates, proteins, N, P, and other micronutrients. This review will focus on recent advancement in the utilization of LEA as: (i) utilization as nutrients or carbon sources for microalgae and other organisms, (ii) anaerobic digestion to produce biogas or co-fermentation to produce CH₄ and H₂, and (iii) conversion to other forms of biofuel through thermochemical degradation processes. Possible mutual benefits in the integration of microalgae cultivation-biodiesel production-resulting LEA with anaerobic digestion and thermochemical conversion are also discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.254-260
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• 2012

This study was conduced to ferment high quality wine by using Omija fruit. Dry Omija farmed and dried in the Moonkyung area was used in this study. The Omija was soaked in 10~40 folds of distilled water to extract water-soluble components and the fluid was filtered after soaking for 6 hours at $50^{\circ}C$. Strains of alcoholic yeast were isolated respectively from spoiled Omija extract. Isolated alcoholic yeasts, OM-1 and OM-2, showed a round to ellipsoidal shape and formed white or milky white colonies on a solid YM medium. Two yeasts produced 10.33~11.23% alcohol from Omija extract adjusted to $10^{\circ}Brix$ with sugar. Their abilities to ferment alcohol were higher than those of other yeast strains belonging to Saccharomyces cerevisiae such as KCTC 7296 (standard strain of Korean Biological Resources Center), Makgeolli yeast, or beer yeast. The isolates OM-1 and OM-2 showed similar abilities in alcohol fermentation. However, the wine fermented by OM-2 got a better sensory score especially with color. Growth of OM-2 was significantly accelerated by addition of a 0.1% urea and 0.02% mineral mixture. A vitamin mixture was effective for the growth only when urea was added as well.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1808-1819
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• 2017

Knowledge on the functional characteristics and temporal variation of anaerobic bacterial populations is important for better understanding of the microbial process of two-stage anaerobic reactors. However, owing to the high diversity of anaerobic bacteria, close attention should be prioritized to the frequently abundant bacteria that were defined as core bacteria and putatively functionally important. In this study, using MiSeq sequencing technology, the core bacterial community of 98 operational taxonomic units (OTUs) was determined in a two-stage upflow blanket filter reactor treating pharmaceutical wastewater. The core bacterial community accounted for 61.66% of the total sequences and accurately predicted the sample location in the principal coordinates analysis scatter plot as the total bacterial OTUs did. The core bacterial community in the first-stage (FS) and second-stage (SS) reactors were generally distinct, in that the FS core bacterial community was indicated to be more related to a higher-level fermentation process, and the SS core bacterial community contained more microbes in syntrophic cooperation with methanogens. Moreover, the different responses of the FS and SS core bacterial communities to the temperature shock and influent disturbance caused by solid contamination were fully investigated. Co-occurring analysis at the Order level implied that Bacteroidales, Selenomonadales, Anaerolineales, Syneristales, and Thermotogales might play key roles in anaerobic digestion due to their high abundance and tight correlation with other microbes. These findings advance our knowledge about the core bacterial community and its temporal variability for future comparative research and improvement of the two-stage anaerobic system operation.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.653-658
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• 2012

This study was conducted to estimate the potential acid production value (PAPV) of major diets and to determine the relationship between dietary PAPV and dairy production traits. Estimation of PAPV of major cattle feeds was based on an in vitro technique, which determined the degree of Ca dissociation from $CaCO_3$. Data on feeds and production traits were collected on 744 multiparous lactating Holstein dairy cows from five different farms. Grains had high PAPV with variable protein sources and by-products. High PAPV feedstuffs had a higher total gas production and lower pH compared to those with low PAPV. Dietary PAPV had a positive correlation with intake of dry matter, NDF, ADF, milk yield and milk solid production but a negative correlation with milk protein and milk fat concentration. Current results indicate that dietary PAPV can be utilized in predicting dairy production traits.

• Biomedical Science Letters
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• v.27 no.4
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• pp.291-297
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• 2021

Codonopsis lanceolata, called deodeok in Korean, has been verified for various effects, including anti-aging and anti-inflammatory effects and insomnia improvement, and is one of the healthy foods that Koreans enjoy eating. In this study, the saponin content, lansemaside A content, and total saponin content of deodeok were analyzed using high-pressure sterilization and solid fermentation by mixed lactic acid bacteria. The antioxidant effect was compared to determine improved processing methods of deodeok. The lansemaside A content of deodeok samples depending on the preprocessing methods was analyzed: 2,594.10 mg/kg for dried deodeok, 2,100.93 mg/kg for steamed deodeok, and 1,151.31mg/kg for fermented deodeok. The total saponin content was found to be 7,209 mg/kg for dried deodeok and 8,605 mg/kg for steamed deodeok, showing a high saponin content. The total polyphenol content was highest for dried deodeok, steamed deodeok, and fermented deodeok. As for the antioxidant effect, it was analyzed that the effect of dried deodeok was the highest, followed by steamed deodeok and fermented deodeok; Dried deodeok had the highest value in total polyphenol content, not in total saponin content, which is considered to have a positive influence on its antioxidant effect. The content of lansemaside A was the highest for dried deodeok. When fermented deodeok is consumed, more beneficial effects on health can be expected by ingesting it with lactic acid bacteria cultured using saponins and polyphenols. Therefore, this study suggests the possibility of manufacturing products suitable for the needs of consumers, such as the flavor of deodeok, according to the processing methods.

• KSBB Journal
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• v.23 no.4
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• pp.345-349
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• 2008

To enhance the value as a feedstuff of distiller's dried grain (DDG) and develop fermented feedstuff, we investigated the effects of the culture conditions affecting glucoamylase activity, such as pH in submerged culture and moisture content in solid-state culture. Also, we investigated the optimal mixing ratio of DDG and wheat bran for the production of fermented feedstuff containing high content of amino acids. In culture conditions for high fermented activity, pH and moisture were optimum at pH 4 and 60%, respectively. In the case of mixing ratio, the glucoamylase activity was decreased with increase of DDG content. On the other hand, the content of crude protein was increased slowly. For the development of fermented feedstuff, the optimal mixing ratio of DDG and wheat bran was 1 to 4. Finally, we could produce approximately 1 ton (dry matter) of trial product in incubator of pilot-scale. The glucoamylase activity and the crude protein content were 1,024 U/g and 33.6%, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.87-95
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• 2003

Although extensive studies were conduced on hydrogen fermentation of organic wastewaters, little is known about biohydrogen production from organic solid wastes. The leaching-bed reactor treating food waste by heat-shocked anaerobic sludge was, therefore, operated at D of 2.1, 3.6, 4.5 and $5.5d^{-1}$ to find optimal D for hydrogen production. Successful operation of a reactor can be accomplished when it is operated at proper dilution rate (D). Operation at high D leads to the washout of biomass in the reactor while operation at low D leads to product inhibition due to the accumulation of excess VFA. These appear to limit the production of hydrogen to reach a higher level. All the reactors showed that, on day 1-3, hydrogen production was dominant and VFA concentration was higher than ethanol. Butyrate and acetate were major components of VFAs over the whole operation, though lactate was very high on day 1-2. Compared with other D values, D of $4.5d^{-1}$, resulted in higher butyrate/acetae (B/A) ratios during the fermentation. The trend of B/A ratios was similar to the hydrogen production, suggesting that butyrate formation favored hydrogen production. Ethanol increased significantly from day 4 when hydrogen Production stopped. It indicated that heat-shocked sludge was able to induce a metabolic flow from hydrogen-and acid-producing pathway to solvent-producing pathway. Operation at D of $4.5d^{-1}$ led to higher fermentation efficiency (58%) than those (51.5, 55.3 and 53.7%) at 2.1, 3.6 and $5.5d^{-1}$. The COD removed was convened to hydrogen (10.1%), VFA (30.9%), and ethanol (17.0%).

• Journal of Life Science
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• v.34 no.7
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• pp.485-492
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• 2024

Sea cucumbers contain more than 50% protein in their solid content, and they also possess various bioactive substances such as saponins and mucopolysaccharides. This study analyzed the activities of various enzymes derived from Bacillus and lactic acid bacteria and determined to degrade the components of sea cucumbers. Among the analyzed strains, B. subtilis K26 showed the highest activities in protease and xylanase and relatively high activity in cellulase. Accordingly, samples of sea cucumber and water were mixed in equal proportions, sterilized, and then fermented by inoculating them with B. subtilis K26. Following this, a higher amino acid content was observed between 1.5 and 7.5 hr, a lower residual solid content in this time, and a lesser fermentation odor. The saponin content in fermented sea cucumber powder extracted with butanol was measured to be 1.12 mg/g. The chondroitin sulfate content was evaluated to be 5.11 mg/g in raw sea cucumber. The total polyphenol content, flavonoid content, and antioxidant activities were 6.95 mg gallic acid equivalent/g, 3.69 mg quercetin equivalent/g, and 3.69 mg quercetin equivalent/g in raw sea cucumber, respectively. Moreover, the DNA damage protective effect of fermented sea cucumber extract was found to be concentration-dependent, with a very strong effect at very low concentrations. Overall, we suggest that sea cucumber fermented with B. subtilis K26 has a high potential as a food for inhibiting oxidation, enhancing immunity, and improving muscle function in the human body thanks to its high free amino acid content.

• Food Science and Preservation
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• v.18 no.6
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• pp.891-897
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• 2011

Oak barrel have been used for a long time for the aging of wine. Instead of oak barrel aging, however, roasted oak chips can be directly added in the wine before aging. In this study, Korean oak chips roasted for different time durations were used for the red wine aging, and the properties of wine aged through the addition of the roasted oak chips were characterized. No significant differences were observed in the alcohol, soluble-solid, reducing-sugar and total-acid contents based on the oak chips aging, but the total phenol content increased. The methanol, ethyl acetate, propanol, isobutanol and isoamyl alcohol contents also increased. Especially, the methanol and propanol contents increased as the roasting time was prolonged. Although the hue values were similar to one another, the intensity as well as the lightness, redness, and yellowness values were high in the wine aged with the roasted oak chips. In the sensory evaluation, the wine aged with oak chips roasted for 2 h showed the highest scores in the flavor, taste, and overall preference.