• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.494-500
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• 2016

In order to remove acetyl group from yellow poplar, deacetylation was performed using sodium hydroxide (NaOH) prior to oxalic acid pretreatment. During the deacetylation ($60^{\circ}C$ for 80 min, 0.8% NaOH), most of the acetyl group were removed from hemicellulose. Simultaneous saccharification and fermentation (SSF) and semi-SSF were carried out based on solid loading (10, 12.5, 15%) of deacetylated biomass and pre-hydrolysis with enzymes (0, 6, 12, 24 h). The highest ethanol was obtained as 26.73 g/L after 120 h when 10% of biomass was used for SSF. It is corresponding to 88.41% of theoretical ethanol yield. At the 12.5% and 15% of biomass loading, the highest ethanol was obtained from 6 h pre-hydrolysis. It was 32.34 g/L and 27.15 g/L, respectively, and corresponding to ethanol yield of 85.58 and 59.87%. In order to remove fermentation inhibitors from hydrolysates, overliming was performed using calcium hydroxide ($Ca(OH)_2$). The highest ethanol was 5.28 g/L after 72 h of fermentation.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.360-363
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• 2008

Two barley malt samples were selected at two different stages of germination, a well-modified malt germinated for 96 hr and a poorly-modified malt for 60 hr, and were analyzed for total, insoluble, and soluble ${\beta}$-glucan contents. The total ${\beta}$-glucan content in raw barley was 3.96%, and the content was reduced during malting. The total ${\beta}$-glucan contents of the poorly- and well-modified malts were 1.02% and 0.18%, respectively. After 4 days of germination, approximately 95% of the ${\beta}$-glucan present in the barley was degraded. A significantly higher proportion of water-soluble ${\beta}$-glucan was found in the well-modified malt, suggesting that ${\beta}$-glucan solubility was dependent on cell wall modifications in the malt (${\beta}$-glucan breakdown). The proportion of water-soluble ${\beta}$-glucan was also affected by the extraction temperature. The two differently modified malts were mashed isothermally at 45, 55, 65, and 75oC for 2 hr. An increasing mashing temperature resulted in increased viscosity for the wort and the resulting beer. The viscosity of the wort from the well-modified malt was significantly low, due to its low initial malt ${\beta}$-glucan with increased solubility as well as a presumably sufficient ${\beta}$-glucanase activity during mashing.

• Applied Biological Chemistry
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• v.12
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• pp.25-31
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• 1969

The characteristics of crude enzyme produced from Trichoderma viride($O_2-1$) which isolated from half spoiled Locust acacia wood (Robinia Pseudacacia Linne) were examined in this paper. The results obtained were summarized as follows: 1) As a results of enzymatic action on several cellulose substrate it was found that there were some sorts of cellulase in crude enzyme. 2) The activity of C.M.C. ase and ${\beta}-glucosidase$ were decreased in accordance with increasing concentration of substrate, and filter paper saccharifying enzyme relatively increased in accordance with increasing concentration of substrate and enzyme in couse of time. 3) The optimal pH of each enzyme was 5.0 and the range of stability on pH generally from 3 to 6. 4) In disintegrating activity on filter paper, in decomposing activity on C.M.C. and $p-nitrophenyl-{\beta}-D-glucoside$, and in saccharifying activity on filter paper, the optimal temperatures were $50^{\circ}C.,\;60^{\circ}C,\;and\;65^{\circ}C$. 5) The order of stability on temperature was as follow; saccharifying activity on filter paper decomposing activity on C.M.C. disintegrating activity on filter paper>decomposing activity on $p-nitrophenyl-{\beta}-D-glucoside$. 6) The activity of the enzymes was inhibited with mercuric and silver ion, and activated with potassium.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.399-404
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• 2012

The objective of this study was to investigate the efficient pretreatment method for bioethanol production from rice hull. Ammonia and sodium hydroxide as an alkaline solution and dilute sulfuric acid as an acidic solution were used in a batch reactor under high-temperature and high-pressure conditions. The highest enzymatic saccharification efficiency of 82.8% and ash removal rate of 94.7% were obtained in the dilute sulfuric acid treated sample after the sodium hydroxide solution treatment. The enzymatic saccharification efficiencies and ash removals of pretreated rice hull samples have very similar variation tendency. This means that the maximum obstructive factor for the enzymatic saccharification of rice hull is the ash (silicate) content in biomass. The findings suggest that the combined sodium hydroxide-dilute sulfuric acid treatment system under high-temperature and high-pressure conditions is a promising pretreatment method to enhance the enzymatic saccharification of the silica-rich biomass.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.306-311
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• 2012

This study was performed to evaluate the effects on saccharification and alcohol fermentation, according to the size of the ground rice (12, 20, 35 mesh) and ultra sonication process (15, 30, 60, 120 min). After saccharification of the ground rice samples for 3 h at $60^{\circ}C$, sugar content was observed to be high in the order of cooked ground rice (CGR) > ultrasonicated ground rice (UGR) > ground rice (GR), in all sizes of ground rice. Further, higher sugar content was obtained by increasing the time of ultrasonication process. Almost 90% saccharification of CGR ($11.5^{\circ}Bx$) could be reached up to $10.2^{\circ}Bx$ by ultrasonicating 35 mesh ground rice for 120 min. After alcohol fermentation on the 35 mesh saccharified-UGR for 4 days at $25^{\circ}C$, 16.7% alcohol concentration could be obtained, as high as of CGR (17.2%). After 4 days of alcohol fermentation, UGR showed a lower pH and a higher acidity (pH 4.06-4.17, 0.99-1.1%) than CGR (pH 4.27, 0.75%).

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.308-312
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• 2010

Deinococcus geothermalis is a moderate thermophillic radiation resistant bacterium producing greater abundance of sugar metabolism enzymes than other Deinococcus species. In this study, optimal condition for xylanolytic activity of D. geothermalis was determined and xylooligosaccharides from oat spelt, beechwood, and birchwood xylan hydrolysates by this organism were analyzed through HPLC. Reducing sugar yield was increased in the order of beechwood, birchwood, and oat spelt xylan. D. geothermalis displayed maximal xylanolytic activity at $40^{\circ}C$ and pH 8.0. Magnesium ion increased xylanolytic activity upto 7.5 fold. Six kinds of xylooligosaccharides (xylose, xylobios, xylotriose, xylotetraose, xylopentaose, and xylohexalose) were detected from beechwood and birchwood xylan reaction products. Among them, xylose was the major product. However, only three kinds of xylooligosaccharides (xylose, xylopentaose, and xylohexalose) were clearly detected from oat spelt xylan. Gamma-ray (50 kGy) treatment of beechwood xylan, birchwood xylan and oat spelt xylan increased xylanolytic activity of D. geothermalis. The results indicate that D. geothermalis and pretreatment of radiation is useful for xylooligosaccharides production.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.18 no.1
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• pp.64-80
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• 1992

Considerable interest has been generated in age-related non-enzymatic glycosylation and crosslinking of collagen in view of its extracellular nature, and its long biological half-life. The effects of UVA, which penetrates deep in dermis, and reactive oxygen species (ROS) on age- related changes of dermal collagen were studied. The amount of nonenzymatic glycosylation, fragmentation, and crosslinking of collagen were monitored from the mixtures of Type I collagen from calf skin and glucose, irradiated by UVA, with or without scavengers of ROS. At both high and low glucose dosages, non-enzymatic glycosylation was not affected by UVA irradiation. At high glucose dosage, however, glycosylation was reduced by the scavengers of superoxide radical and singlet oxygen, bolt not by hydroxyl radical scavengers. Fragmentation was increased by UVA and decreased by all ROS scavengers. Crosslinking was also enhanced by UVA, and effectively blocked crosslinking. Superoxide radical and singlet oxygen, which were produced by autoxidation of glucose independently to UVA, may encounter the initial phase of glycation. ROS generated from Amadory compounds by UVA enhanced fragmentation and crosslinking Hydroxyl radical was thought to be a major ROS affecting crosslinking. These results suggest that UVA and ROS are able to enhance age-related structural changes of collagen, as affecting many other tissue and cellular components.

• Food Science and Preservation
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• v.21 no.4
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• pp.573-580
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• 2014

The enzymatic activity of Nuruk and the quality properties of Yakju were investigated according to different fungi. The fungi that were used in this study were Aspergillus kawachii KCCM 32819, Aspergillus niger KCCM 32005, Rhizopus japonicus KCCM 11604, Rhizopus oryzae KCCM 11272, Rhizopus oryzae KCCM 11273, Rhizopus oryzae KCCM 11276, and Mucor rouxii KCCM 60148. The study results are as follows. The saccharogenic power of Rhizopus oryzae KCCM 11272 Nuruk was the highest (3,647.72 SP/g) among all the samples. The ${\alpha}$-amylase production and protease activities were highest (3.76 DU and 4.7 tyrosine mg/min, respectively) in the Rhizopus japonicus KCCM 11604 Nuruk. The pH levels of the Yakju made with commercial Nuruk and Rhizopus japonicus KCCM 11604 Nuruk were 4.14 and 4.07, respectively. The total titratable acid content of the Yakju made with Rhizopus oryzae KCCM 11273 Nuruk was the highest (0.56%) among all the samples. Rhizopus japonicus KCCM 11604 and Rhizopus oryzae KCCM 11272 had the highest ethanol yields (15.18% and 15.10%, respectively). In the sensory evaluation carried out in this study, the panel preferred the Yakju made with Rhizopus japonicus KCCM 11604 Nuruk. Overall, however, the panel did not like the Yakju made with Aspergillus niger KCCM 32005 Nuruk.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.350-354
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• 1985

For the purpose of studying the possibility to use the barley as a raw material in vinegar manufacturing process, several factors related to the fermentation of acetic acid were investigated. The optimum quantity of sweet liquor prepared by koji method in medium was 30-40%. When koji of A. oryzae, commercial enzyme products and malt were used for the saccharification of the barley, the production rates of acetic acid during log period were 0.056%/hr, 0.025%/hr, 0.03896/hr and lag period were 22 hours, 48.5 hours and 25 hours, respectively. These results indicate that the saccharifying method using koji of A. oryzae is superior to that by the commercial enzyme products or malt for the acetic acid fementation. The optimum initial acidity was 2% and the proper initial ethanol degree were 4-6% in metium. In a submerged culture process using a jar fermentor, lag period was 15 hours, and acetic acid fermetation period was about 45 hours. In the sensory test of barley vinegar and commercial vinegar of the market, barley vinegar was superior to the vinegar in market with respect to tastes.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.349-357
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• 2019

The purpose of this study was to investigate the effects of body mass index(BMI) on insulin. fasting blood sugar(FBS), and hemoglobin A1c(HbA1c). This study analyzed the data of 2015, The Sixth KNHANES, and it was included to 4554 subject over 20 years old. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression analysis(SPSS 25.0). The major findings, BMI was positively correlated with insulin(r=0.397, p<0.001), FBS(r=0.241, p<0.001), and HbA1c(r=0.237, p<0.001). Factors affecting insulin are overweight(${\beta}=.130$, t=8.193, p<0.001), obesity(${\beta}=.390$, t=24.390, p<0.001) and age. the explanatory power is 13.1% (F=53.584, p<0.001). Factors affecting FBS were overweight(${\beta}=.072$, t=4.478, p<0.001), obesity(${\beta}=.186$, t= 11.485, p<0.001), age, the explanatory power was 10.6% (F=42.351, p<0.001). Factors affecting HbA1c were overweight(${\beta}=.059$, t=3.712, p<0.001), obesity(${\beta}=.190$, t=11.895, p<0.001) age and sex, the explanatory power is 14.1% (F=58.134, p<0.001). Based on this study result, diabetes mellitus prevention and management programs should include interventions related to obesity.