• Journal of Plant Biotechnology
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• v.34 no.2
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• pp.111-118
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• 2007

Global warming crisis due primarily to continued green house gas emission requires impending change to renewable alternative energy than continuously depending on exhausting fossil fuels. Bioenergy including biodiesel and bioethanol are considered good alternatives because of their renewable and sustainable nature. Bioethanol is currently being produced by using sucrose from sugar beet, grain starches or lignocellulosic biomass as sources of ethanol fermentation. However, grain production requires significant amount of fossil fuel inputs during agricultural practices, which means less competitive in reducing the level of green house gas emission. By contrast, cellulosic bioethanol can use naturally-growing, not-for-food biomass as a source of ethanol fermentation. In this respect, cellulosic ethanol than grain starch ethanol is considered a more appropriate as a alternative renewable energy. However, commercialization of cellulosic ethanol depends heavily on technology development. Processes such as securing enough biomass optimized for economic processing, pretreatment technology for better access of polymer-hydrolyzing enzymes, saccharification of recalcitrant lignocellulosic materials, and simultaneous fermentation of different sugars including 6-carbon glucose as well as 5-carbon xylose or arabinose waits for greater improvement in technologies. Although it seems to be a long way to go until commercialization, it should broadly benefit farmers with novel source of income, environment with greener and reduced level of global warming, and national economy with increased energy security. Mission-oriented strategies for cellulosic ethanol development participated by government funding agency and different disciplines of sciences and technologies should certainly open up a new era of renewable energy.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.558-561
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• 2008

Culture broth of Bacillus subtilis Y3-7 in tryptic soy broth (TSB) isolated from Korean traditional fermented food was evaluated for the inhibition of $\alpha$-glucosidase. The results of in vitro studies using the yeast $\alpha$-glucosidase demonstrated that the culture broth exerted inhibitory effects on $\alpha$-glucosidase with $IC_{50}$ value of 1.62 mg/mL, and functioned as a competitive inhibitor. Furthermore, the culture broth of B. subtilis Y3-7 significantly improved glucose tolerance in normal and streptozotocin-induced diabetic mice. The blood glucose levels in the mice receiving sucrose supplementation in the culture broth (1 g/kg, 2 g/kg) were measured at 48.7%, which corresponded to 22.2% of the levels measured in the control mice. These results indicated that the culture broth of B. subtilis Y3-7 in TSB might be considered as a useful compound for the preparation of functional foods for diabetic patients.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.238-244
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• 1983

The cooking quality of irradiated chestnut after longterm storage were evaluated. 1. Color degree and tannin content of irradiated chestnut were slightly increased with the storage, but there was a little difference according to the radiation dose after nine months storage. 2. The main component of free sugars in the irradiated chestnut were identified as sucrose, glucose, fructose and the amino acids of chestnut were identified in the decreasing order of glutamic acid, aspartic acid, leucine, arginine, glycine, alanine, serine, pheylalanine, threonine, valine, isoleucine, tyrosine, methionine and cystein. Free sugars and amino acids of 25 Krad irradiated group showed a little difference compared with those of control group after nine months storage. 3. The calorie of candied chestnut prepared from nine months stored was marked 199 Kcal/100g of edible parts compared with 159 Kcal of raw chestnut. 4. Texture and sensory evaluation of candied chestnut prepared from nine months stored were better in 20-25 Krad irradiated group than in control group.

• Journal of Ginseng Research
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• v.30 no.1
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• pp.41-48
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• 2006

In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred In initial stage of steaming fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after steaming. Browning reaction of red ginseng occurred between $60{\sim}90$ min of steaming at $100^{\circ}C$, and browning pigments of red ginseng were mostly water soluble substances. The structural characteristics of water soluble browning reaction products(WS-BRPs) isolated from Korean red ginseng were showed the presence of hydroxyl, amide carbonyl and aliphatic methane groups. From sugar analysis it was identified that L and S-1, melanoidins isolated from red ginseng, contained two kinds of sugars, glucose and xylose, and the other melanoidin S-2 contained the previous and fructose. In order to find out pertinent methods for the acceleration of browning during ginseng processing, various treatment were made on fresh ginseng with sugars, amino acids and inorganic nitrogenous compounds and the extent of browning was measured. Among sugar tested, maltose resulted in the greatest acceleration of browning followed in decreasing order by glucose and lactose, whereas pentoses, fructose, sucrose and raffinose had negligible effect. A marked browning occurred in ginseng treated with basic amino acids, while the extent of browning was not greatly increased when ginseng was treated with aliphatic amino acids, hydroxyl amino acids, or acidic amino acids. The brown color intensity gradually increased with an increase of glucose concentration far up to 0.5M. L, S-1, and S-2 were found to have an ability to donate hydrogen to DPPH, and also they had anti-oxidative activity in the experiments of hydrogen peroxide scavenging, inhibitory activity in the formation of MDA from linoleic acid, auto oxidation of ok-brain homogenates, lipid peroxidation by the enzymatic and non-enzymatic system in liver microsome fraction, and mitochondrial fraction etc. The amounts of acidic polysaccharide(AP) in red ginseng were higher than those of wild and cultured Panax quinquefolius, Panax notoginseng as well as white ginseng (Panax ginseng). In white ginseng, the AP amount is no difference in root ages or sizes, also, the AP amount of ginseng body was similar to that of rhizome, but was higher than that of leaf and epidermis. Addition of red ginseng acidic polysaccharide(RGAP) increased production of nitric oxide(NO) and tumor necrosis factor (TNF)-$\alpha$ in the rodent macrophage cultures, and treatment of RGAP in vivo stimulated tumoricidal activities of natural killer (NK) cells.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.552-556
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• 1994

It was aimed to study the chemical characteristics and volatile compounds of juices extracted by press (PE) and centrifugal extractors (CE). Citrons cut up cross direction were used as samples in PE. Proportion ratio of peel, flesh, and seed of citron were 43.9, 39.4 and 16.7%, respectively. Yield of juice increased with weight to 120g of citron fruit. pH, brix, pulp, oily materials, amino nitrogen and yield of juice extracted by CE were higher than those of juice by PE. Acidity and transmittance of juice extracted by PE were higher than those of juice by CE. Free sugars of citron juice were consisted of fructose, glucose and sucrose. Free sugar contents of juice by CE were twice as much as those of PE. Major volatile compounds of total steam distillation matters of citron juice extracted by PE were dl-limonene, ${\gamma}-terpinene\;{\beta}-farnesene$, sabinene, linalool, ${\beta}-myrcene$ and terpinolene, while those by CE were dl-limonene, ${\gamma}-terpinene$, sabinene, ${\beta}-myrcene,\;{\alpha}-pinene$, linalool and terpinolene. dl-Limonene and ${\gamma}-terpinene$ consisted of $73{\sim}83%$ of total volatile compounds. dl-Limonene of juice by CE increased about 6% that of juice by PE. ${\beta}-Farnesene$ were observed trace in juice by CE but presented in 7% in juice by PE. The results would suggested that chemical characteristics and volatile compounds of citron juice seemed to depend on extraction methods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1516-1521
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• 2010

This study was conducted to investigate the physicochemical and quality characteristics of alcohol fermentation of tomato. For yeast, Saccharomyces bayanus Lalvin EC-1118 displayed the highest alcohol content (11.8%), whereas titratable acidity and pH did not differ significantly between different yeasts. Alcohol fermentation conducted at higher temperature ($25^{\circ}C$) resulted in higher alcohol content and lower sugar level. The highest alcohol content was produced using 11.4% sucrose and 11.1% fructo-oligosaccharide. These two saccharides were suitable for tomato alcohol fermentation. Lycopene levels were similar regardless of sugar type, and were approximately 4.2 mg%. To improve lycopene content, three types of fruit wine with low-dose lycopene (LDL), medium-dose lycopene (MDL), and high-dose lycopene (HDL) were made. Their alcohol contents were not significantly different (10.0~10.8%). Lycopene contents of LDL, MDL, and HDL wine were 4.25 mg%, 11.40 mg%, and 20.45 mg%, respectively. Therefore, HDL tomato wine should be manufactured.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.390-398
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• 2018

Miscanthus is a perennial energy plant that reproduces via rhizomes and has C4 metabolism. The flowering pattern of a wild type M. sacchariflorus (WTM) is affected by environmental conditions such as photoperiod and soil water status. Geodae-Uksae 1 (Geodea), which is a new M. sacchariflorus cultivar, has a lower heading rate than WMS; however the mechanism with why this happens is unknown. To confirm the effects of drought or waterlogging stresses on the growth of WTM and Geodea at the reproductive stage, we investigated variations in morphological characteristics and nutrient contents of the two Miscanthus species after four months of three water treatments. Morphological traits of the two Miscanthus species under the drought condition were similar to those under the control condition. But, the height of Geodea increased by 30% in response to the waterlogging stress. In WTM, the heading rate under the drought condition was lowest, while there was no significant difference between the waterlogging and control conditions. In the two Miscanthus species, nutrient contents, such as sucrose, total N, $P_2O_5$, K and Mg, were the highest under the drought condition, wherea Ca and Mg contents under the waterlogging condition were more than three times lower than those under the drought condition. The current study results showed that drought stress accelerated senescence and then inhibited nutrient mobilization in WTM, while waterlogging stress promoted the growth. This study is the first report to confirm that waterlogging stress promotes flowering of M. sacchariflorus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.335-341
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• 2013

Kyungokgos purchased in local markets in Korea vary in their combination and mixing ratios during processing. This study was investigated qualities of Kyungokgos manufactured traditionally to evaluating its qualities. The general components of Kyungokgos were moisture (18.62~49.78%), ash (0.198~1.211%), protein (0.89~3.58%), lipid (0.16~1.14%) and carbohydrates (47.95~77.08%). The color values of L, a, and b were 26.49~73.87, 16.51~38.64, and 45.41~88.94, respectively. The viscosity was classified into three non-Newtonian type groups: high, medium, and non-dilatant, according to the increase of loop execution times. Three extracts (KOG-1, -7, and -8, in a 30-fold dilution) showed no cytotoxicity toward RAW 264.7 cells, while the extracts of KOG-2, -4, and -5 showed a low cytotoxic effect. KOG-1 and -2 extracts with low cytotoxicity markedly inhibited the production of the inflammatory mediators-nitric oxide (NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in LPS-stimulated RAW 264.7 cells. These results indicate that KOG-1 and -2 extracts have anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophages.

• Journal of Applied Biological Chemistry
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• v.54 no.2
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• pp.126-134
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• 2011

In this study, the characteristics of alcohol fermentation using ripe Daebong persimmon juice were studied in static fermentation condition by Saccharomycess cerevisiae CS02 in an effort to develop new types of functional wine. Attempts were made to modify the ripe Daebong persimmon juice in order to find suitable conditions for alcohol fermentation. The modified ripe Daebong persimmon juice that was most suitable for alcohol fermentation contained $24^{\circ}brix$ of sugar supplemented with sucrose as a carbon source and 0.5 g/L of $(NH_4)_2HPO_4$ as a nitrogen source. After 9 days of fermentation at $25^{\circ}C$, $12.2{\pm}0.02%$ of alcohol was produced from the modified juice and its pH markedly decreased to $3.97{\pm}0.02$. The wine contained free sugar such as fructose ($0.12{\pm}0.02$ g/L), some organic acids such as malic acid ($35.92{\pm}0.24$ g/L), succinic acid ($8.12{\pm}0.03$ g/L), oxalic acid ($22.14{\pm}0.11$ g/L), and citric acid ($13.63{\pm}0.08$ g/L), as well as some flavanols and phenolic acids such as catechin gallate ($38.99{\pm}0.32$ mg/L), epicatechin gallate ($110.21{\pm}0.16$ mg/L), gallic acid ($163.88{\pm}1.11$ mg/L), epigallocatechin ($15.97{\pm}0.18$ mg/L), and tannic acid ($13.36{\pm}0.02$ mg/L). In addition, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (84.25%) and $ABTS^{\cdot+}$ radical (99.65%) scavenging activities were increased significantly with a corresponding increased in the organic acid and phenolic acid contents, but decreased in the flavonoids.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.550-555
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• 1997

Vibrio cholerae non-O1 (V. cholerae non-O1) was previously called nonagglutinable or noncholera vibrios, since it fails to react with polyvalent O1 antisera. This organism is biochemically and genetically indistinguishable from V. cholerae O1 except serological difference. V. cholerae non-O1 strains are often detected in the environment including bays, estuaries, and fresh water, and also found in food. Therefore it is designated food borne bacterium in Japan. However, research papers on V. cholerae non-O1 are very rare in Korea. In order to investigate bacteriological characteristics of V. cholerae non-O1, we isolated V. cholerae non-O1 from the environmental sea water. Among the isolated V. cholerae non-O1 strains, we selected the strain which had the most strong hemolytic activity, named as V. cholerae non-O1 FM-3. The optimum growth conditions of V. cholerae non-O1 FM-3 were $37^{\circ}C$ and pH 8.5 in BHI broth (containing $0.5\%$ sodium chloride), and it grew better than V. cholerae non-O1 ATCC 25872. But both were not able to grow in BHI broth added $5.0\%$ of sodium chloride or adjusted to pH 5.0. According to the experimental results on the susceptibility test against various antibiotics, there were no significant differences between the isolated strain and reference strain (V. cholerae non-O1 ATCC 25872). Most of the antibiotics examined had bacteriostatic action against V. cholerae non-O1 FM-3 while vancomycin, oxacillin, colistin, polymyxin B, and sulfadiazine had no bacteriostatic activity.