• Horticultural Science & Technology
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• v.30 no.4
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• pp.409-416
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• 2012

The amount of cellular components including soluble sugars, amino acids, organic acids and glucosinolates (GLS) was investigated during radish root processing to develop a radish beverage. The radish root was divided into two parts, white and green tissue, and processed separately by extracting the juice from the fresh tissue and from the boiled tissue to compare differences in the components content among the preparations. The overall palatability of both the fresh and boiled extracts from the green part of the radish was higher than that of the same extracts from the white part. The sweetness of extract by boiling increased and its pungency decreased, thereby the palatability increased by being compared to the fresh radish extract. The sweetness was affected by sucrose not by glucose or fructose of monosaccharides by showing different sucrose contents according to treatment comparing palatability. Malic acid was identified as primary organic acid, and the content was higher in both the fresh and boiled extracts from the white part than in the extracts from the green part of the radish. The fresh extract from the green part of the radish contained more essential amino acids, such as threonine and valine, and more hydrophilic amino acids including glutamic acid, aspartic acid, and arginine than those of the fresh extract from the white part, suggesting the green fresh part is more palatable than the white fresh part. The main sulfur compound was ethylthiocyanate in radish, and others were butyl isothiocyanate, dimethyl-disulfide, and 4-methylthio-3-butylisothiocyanate. The four GLS were detected much more in the fresh green and fresh white parts of the radish because they evaporated during boiling. The contents of the four sulfur compounds were higher in the white fresh part than in the green fresh part, which is likely the reason the pungency was higher and the palatability was lower in the white fresh part than in the green fresh part of the radish. The ascorbic acid content was higher in the fresh extract compared to the boiled extracts from both the green and white parts. Taken together, these findings indicate that fresh radish extract is superior to obtain in terms of retaining desirable nutritional and functional components for health.

• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.211-215
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• 2015

The hydrolysis of defatted rice bran using near-critical water was performed, and the feasibility of consequent hydrolyzate as a growth medium was investigated by the cultivation of Saccharomyces cerevisiae. The near-critical water hydrolysis was carried out through a series of batch experiments, and the contents of total carbohydrates, disaccharides, and monosaccharides, total organic carbon (TOC), total nitrogen (TN), pH of products were measured. The growth rate of Saccharomyces cerevisiae was measured with optical density. The yield of total carbohydrates, TOC, and TN increased with temperature below $240^{\circ}C$, however, decreased above $240^{\circ}C$. The decrease of yields above $240^{\circ}C$ was caused by the formation of organic acids, and it agreed with the change of pH of products. The yield of glucose was a maximum at $200^{\circ}C$ and it decreased dramatically at higher temperature. The growth rate of Saccharomyces cerevisiae cultivated in the hydrolyzate was similar with that in the commercial medium under certain conditions. The growth rate was correlated with the content of glucose in hydrolyzate.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.91-95
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• 2009

To examine physico-chemical properties of the polysaccharide extracted from liquid-cultured mycelia of Schizophyllum commune, each the polysaccharide was extracted with hot water treatment and then fractionated with ethanol, alkaline solution and ultrafiltration. And we determined carbohydrate contents, composition of amino acids, infra-red spectrum and viscosity. Carbohydrate contents of polysaccharide treated with ethanol and ultrafiltration were 72.0% and 62.3%, and proteins content were 15.3% and 32.0% respectively. The carbohydrate consisted of four monosaccharides and the protein contained 16 amino acids. The polysaccharide obtained from ultrafiltration was shown an absorption band characteristic of the ${\beta}$-glycosidic linkage by infra red spectra. These results suggest that the polysaccharide extracted from Schizophyllum commune showed the characteristics of proteinbounded polysaccharide, and it was ${\beta}$-glycosidic linkage with strong viscosity.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.570-579
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• 2020

Background: Many researchers reported that the various immune activities of red ginseng are due to acid polysaccharides. But, the exact structural characteristics of the acidic polysaccharide in red ginseng have not been fully elucidated. Therefore, we isolated the acidic polysaccharide from red ginseng and characterized the structural property of the active moiety of this polysaccharide, which contributes to the immunostimulatory activity of red ginseng. Methods: A polysaccharide (RGP-AP-I) was purified from red ginseng via size-exclusion chromatography using Sephadex G-100. Immunostimulatary activity of RGP-AP-I was investigated via anti-complementory and macrophage stimulatory activity. The structure of RGP-AP-I was characterized by HPLC, sugar composition, β-glucosyl Yariv reagent and methylation analysis. Results: Peritoneal macrophages stimulated using RGP-AP-I significantly augmented the production of various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factor (TNF)-α. The primary structure of RGP-AP-I was elucidated by assessing its sugar composition and methylation analysis. RGP-AP-I is a 96 kDa acidic polysaccharide, and comprises nine different monosaccharides, which mainly include sugars such as rhamnose (Rha, 9.5%), galacturonic acid (GalA, 18.4%), galactose (Gal, 30.4%), and arabinose (Ara, 35.0%). RGP-AP-I exhibited an considerable reaction with the β-glucosyl Yariv reagent, revealing the presence of arabino-β-3,6-galactan. Methylation analysis indicated that RGP-AP-I comprises 21 different glycosyl linkages, such as 3-, 4-, 6- and 3,6-linked Galp; 5-linked Araf; 2,4-linked Rhap; and 4-linked GalAp, which are characteristics of rhamnogalacturonan I (RG-I). Conclusion: we assumed that the immunostimulatory activity of RGP-AP-I may be due to the RG-I structure, which comprises a main chain with a repeating linkage unit, [→2)-Rhap-(1→4)-GalAp-(1→] and three groups of side chains such as (1→5)-linked arabinan, (1→4)-linked galactan, and arabino-β-3,6-galactan, which branch at the C(O)4 positions of Rha residues in the main chain of RGP-AP-I.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.243-248
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• 2011

We studied the repeated-batch process for the bioethanol production from the hydrolysate of Ulva pertusa Kjellman using yeast Pichia stipitis, which is able to assimilate C6- and C5-monosaccharides. During 180-hour operations, the repeated-batch process was carried out stably, and the average bioethanol concentration reached 11.9 g/L from about 30 g/L of reducing sugar in the hydrolysate. Meanwhile, the bioethanol yields, based on the reducing sugar and the quantitative TLC analysis, were 0.40 and 0.37, respectively, which corresponded to 78.4% and 72.5% of theoretical value, respectively. Throughout the quantitative process analysis, it was also demonstrated that 39.67 g-bioethanol could be produced from 1 kg of dried Ulva pertusa Kjellman. In this study, we verified that the bioethanol production from the hydrolysate of Ulva pertusa Kjellman was feasible using a yeast Pichia stipitis, particularly during the repeated-batch operation.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.305-310
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• 2009

Yellow poplar was selected a promising biomass resources for bio-ethanol production through alkali prehydrolysis, enzymatic saccharification and fermentation using commercial cellulase mixtures (Celluclast 1.5L and Novozym 342 mixtures) and fermenting yeast. In alkali prehydrolysis, 51.1% of Yellow poplar biomass remained as residues, which chemical compositions were 82.2% of cellulose, 17.6% of xylan and 2.0% of lignin. In alkali prehydrolysis process, 96.9% of cellulose, 38.0% of xylan and 5.7% of lignin were remained. Enzymatic saccharification by commercial cellulases led to 87.0% of cellulose to glucose and 87.2% of xylan to xylose conversion. Produced glucose and xylose were fermented with fermenting yeast (Saccharomycess cerevisiae), which resulted in selective fermentation of glucose only to bio-ethanol. Residual monosaccharides after fermentation were consisted to 0.4-1.4% of glucose and 92.1-99.5% of xylose. Ethanol concentration was highest for 24 h fermentation as 57.2 g/L, but gradually decreased to 56.2 g/L for 48 h fermentation and 54.3 g/L for 72 h fermentation, due to the ethanol consumption by fermenting yeast.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.153-158
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• 2006

Changes in contents of amino acids, caffeine, trigonelline, chlorogenic acid, and monosaccharides in green coffee beans during roasting were investigated. During roasting, amino acid contents of Arabica and Robusta coffees decreased by 30%, among which cysteine, serine, lysine, and arginine contents markedly decreased, whereas those of glutamic acid, glycine, alanine, valine, isoleucine, leucine, and phenylalanine slightly decreased or increased. Caffeine contents of Arabica and Robusta were 1 and 2%, respectively, and remained unchanged during roasting. Trigonellin content of Arabica (0.87%-0.90%) was slightly higher than that of Robusta (0.74%), and 50 to 65% trigonellin degraded when green beans were heavily roasted. Chlorogenic acid levels of Robusta and Arabica were 4.82, and 4.38-4.66%, respectively. About 90% chIorogenic acid degraded with heavy roating. Total monosaccharide contents of Arabica and Robusta were 38.1-38.7 and 37.7%, respectively, and gradually decreased with roasting.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.324-331
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• 2009

MK1 strain, an obligate aerobic heterotrophic bacterium isolated from the rotten tissue of Neungee mushroom (Sarcodon aspratus), produces a copious amount of exopolysaccharide (EPS), which could evoke macrophage activation. Investigations on optimal culture conditions of MK1 and physical properties of MK1 EPS were made. Glucose, galactose, fructose, and sucrose supported well growth of MK1, but potato starch and dextrin did not. However, lactose seemed to be a less favorable carbon source. Optimal growth of MK1 was obtained at pH 7.0, $30^{\circ}C$, and 200 rpm with 2% glucose, and 0.2~0.05% $(NH_4)_2SO_4$. $EPS_{opt}$ obtained from an optimal growth condition constituted of carbon (37.1%), nitrogen (2.2%), oxygen (49.3%), and hydrogen (6.4%), but no sulfur. Paper chrogromatogram of the acid-hydrolysate of $EPS_{opt}$ suggested that MK1 EPS seemed to be hetropolysaccharide composed of a few number of monosaccharides including amino- and acidic-sugars. Its molecular mass determined by SDS-polyacrylamide gel electrophoresis varied from 14.8 to 47.9 kDa. Physical properties of $EPS_{glu}$ obtained from cell grown in glucose medium, such as relative viscosity ($_{rel}$) and crystalline morphology were rather affected by pH of the growth medium. Relative viscosity ($_{rel}$) of exopolysaccaride (0.1 g/ml) harvested from cells grown at medium pH ranging from 6.0 and 7.5 was 1.23 and 1.39, respectively. The freeze-dried exopolysaccharide obtained at low pH (6.0 and 6.5) was fine crystaloid and water-soluble, whereas those obtained at high pH (7.0 and 7.5) was rather gluey and less water-soluble.

• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.325-331
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• 1995

The effect of cultural conditions on mycelial growth, polysaccharide production in Phellinus linteus and its monosaccharide composition was studied. P. linteus showed the highest growth (0.9 g/100 ml) on glucose but the polysaccharide production was the highest (13.7%) on mannose. The fungus grew very well at neutral pH (0.9 g/100 ml) but the growth was reduced to 0.47 g per 100 ml at alkaline pH. For the different pH, the yield of polysaccharide was in the range of $5{\sim}8%$. The highest yield of 7.94% was obtained at pH 5. Also a variation in monosaccharide composition was observed for different carbon sources and pH. The composition ranges of glucose, mannose, and galactose of polysaccharide were $80{\sim}95%,\;3{\sim}12%,\;and\;2{\sim}10%$ depending on carbon sources, respectively. In contrast, the variation of composition range of three monosaccharides was narrower for different pH than that for carbon sources. These results suggested the possibility of the improvement of production and the physiological modification of the polysaccharide.

• Korean Journal of Ecology and Environment
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• v.36 no.2 s.103
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• pp.108-116
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• 2003

To investigate bacteria with algal Iytic activities against Anabaena cylindrica when water blooming occurs and to study enzyme profiles of alga-Iytic bacteria, various bacterial strains were isolated from surface waters and sediments in eutrophic lakes or reservoirs in Korea. Abacterial strain AK-07 was characterized and identified as Acinetobacter johnsonii based on its16S rDNA base sequence. When AK-07 was co-cultivated with A. cylindrica, bacterial cells propagated to $8\;{\times}\;10^8$ cfu $ml^{-1}$ and Iyses algal cells. However, culture filtrates of AK-07 did not exhibit algal Iytic activities. That suggesting the enzymes on the surfaces of the bacterium might be effective algal Iytic agents to cause Iyses of cells. Acinetobacter johnsonii AK-07 exhibited high degradation activities against A. cylindrica, and formed alginase, caseinase, lipase, fucodian hydrolase, and laminarinase. Moreover, glycosidases for example ${\beta}$-galatosidase, ${\beta}$-glucosidase, ${\beta}$-glucosaminidase, and ${\beta}$-xylosidase, which hydrolyzed ${\beta}$-0-glycosidic bonds, were found in cell-free extracts of A. johnsonii AK-07. Other glycosidase such as ${\alpha}$-galctosidases, ${\alpha}$-N-Ac-galctosidases, ${\alpha}$-mannosidases, and ${\alpha}$- L-fuco-sidases, which cleavage ${\alpha}$-0-glycosidic bondsare not detected. In the results, enzyme systemsof A. johnsonii AK-07 were very complex to do-grade cell walls of cyanobacteria. The polysaccharides or peptidoglycans of A. cylindrica maybe hydrolyzed and metabolized to a range of easily utilizable monosaccharides or other low molecular weight organic substances by strain AK-07 of A. johnsonii.