• Journal of Ginseng Research
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• 제5권2호
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• pp.122-131
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• 1981

An aqueous extract s of fresh ginseng roots was heated at loot for 64 hrs. and the changes of color intensity, pH and the amount of free sugars and amino acids during the various intervals of the heating time were investigated. Color intensity and absorbance of the solution at 490nm were increased in proportion to the length of the heating time. Most of brown pigments produced during the treatment were water soluble, and pH 5.1 at initial stage of the solution, was slightly decreased at the final stages of the reaction. Sucrose, glucose and fructose were major free sugars in ginseng roots, and the amounts of sucrose was over 90 % of total free sugars. Sucrose. was largely decreased approximately 50%, by 64 hrs of the treatment, whereas sharp increase in the amount of glucose and fructose was observed during the reaction in the solution. The observed increase in reducing sugars, glucose and fructose was presumed due to hydrolysis of sucrose. Evidently, glucose and fructose were not important factor to control the browning reaction of the solution. Most of free amino acids and peptides except alanine and isoleucine especially arginine, serine and threonine, were sharply decreased up to 40 : 50% of the original concentration within 2 hrs. Accordingly, the content of free amino acids and peptides seems to be extremely important factor to control the browning reaction in ginseng. A free amino acid, presumed to be nor-leucine, was found in fresh ginseng root on the basis of re mention on liquid chromatography. Kinetic analysis of the browning reaction indicated a pseudo second order with respect to amino acid concentration at the initial stage.

• 한국식품저장유통학회지
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• 제2권1호
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• pp.173-183
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• 1995

This paper was carried out to investigate changes in chromatograms of polysacctatides and soluble pectins on Sephadex G-50 and non-cellulosic neutral sugars of polysaccharides isolated from cell wall of persimmon fruits treated with polygalacturonase and $\beta$-galactosidase in vitro. The chromatogram pattern of soluble pectins extracted from cell wall treated with $\beta$-galactosidase on Sephacryl S-500 column were similar to those of untreatment, but contents of soluble pectins treated with $\beta$-galactosidase were different from those of untreatment. The patterns of chromatograms In soluble pectins extracted from cell wall treated with polygalacturonase were more complex and lower molecular polymer than those of other cell wall-degrading enzyme treatments. Non-cellulosic neutral sugar of polysaccharides in fraction I of soluble material treated with polygalacturonase was rhamnose, those in fraction II were similar to those in fraction III and contents of arabinose, xylose and glucose were higher than contents of other non-cellulosic neutral sugars. Non-cellulosic neutral sugars of polysaccharides in fraction I in soluble material by $\beta$-galactosidase treatment were rhamnose, arabinose, galactose and mannose. Content of glucose of polysaccharides in fraction II was higher than that in fraction I . Non-cellulosic neutral sugars treated with mixed enzyme were rhamnose, fucose, arabinose, xylose, mannose, galactose and glucose. Compositions of non-cellulosic neutral sugars of polysaccharides in fraction I were similar to those in fraction II and III.

• Journal of Nutrition and Health
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• 제18권1호
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• pp.36-45
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• 1985

The effects of glucose, lactose, sucrose, and potato starch on kimchi fermentation and on the stability of ascorbic acid were investigated at $7^{\circ}C$. Kimchi samples with the sugars showed the higher PH and lower total acidity until 9th day of fermentation than kimchi without sugar. Changes in the pH and total acidity were not significantly different among the samples after the 12th day. Addition of the sugars did not show any effects on the growth of lactobacilli through the fermentation period. The amounts and changes in ascorbic acid content during the fermentation did not differ significantly between the control and sugar - added samples. Ascorbic acid in most samples decreased continuously by the 9th day of fermentation. After then the vitamin increased in all the samples and then again decreased slowly after 18th day. From the multiple comparison tests the 10- panel members indicated the better flavor of sugar - added samples than control sample. However the differences in flavor were not significant.

• 한국해양바이오학회지
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• 제15권2호
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• pp.96-102
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• 2023

Salicornia herbacea, a noted halophyte, has been widely researched for its diverse physiological activities. The continuous exploration of its compounds is essential. This study employed gas chromatography (GC) coupled with mass spectrometry (MS) for qualitative analysis. This involved pretreatment including trimethylsilyl (TMS) derivatization of the S. herbacea extract, facilitating its GC analysis. Five compounds, including various fatty acids and β-sitosterol, were identified by direct analysis of the methanol extract of S. herbacea without pretreatment by GC-MS. Conversely, the analysis of the TMS-derivatized extract revealed 28 distinct peaks. Quantitative analysis further indicated that the predominant compounds in the S. herbacea extract were sugars and sugar derivatives, notably glucose, fructose, and glucitol. The collective concentration of these sugars and its derivatives amounted to 116.45 mg/g, representing 11.6% of the dry weight of the raw S. herbacea. Following sugars and their derivatives, fatty acids constituted the next most abundant group of compounds. However, the presence of amino acids and organic acids was relatively low.

• 한국균학회지
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• 제46권4호
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• pp.511-518
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• 2018

Aspergillus nidulans와 Botrytis cinerea와 같은 사상균들은 당과 같은 영양분이 존재하지 않은 조건에서는 발아하지 않는다. 본 연구에서는 A. nidulans의 포자에 당을 인식하는 기구가 존재할 것이라는 증거를 제시하였다. A. nidulans의 포자에 증류수를 가하였을 때에는 발아가 관찰되지 않는 반면에 5%의 글루코오스를 가해 주었을 때에는 98%이상의 포자가 발아하였다. 뿐만 아니라 프록토오스, 설탕, 녹말과 같은 단당류, 이당류, 다당류를 가해 주어도 유사한 결과를 관찰할 수 있었다. 특이한 것은L-형의 아라비노오스를 가해 준 포자는 발아관을 형성하였으나D-형의 아라비노오스를 가해주면 증류수를 가해주었을 때와 같이 발아관을 형성하지 못 하였다. 포자를 트립신으로 처리한 후에 글루코오스를 가해주면 발아율이 25%롤 감소하였다. 포자 표면에 존재하는 단백질을 용출하여 분리한 후 MALDI-TOF 질량분석기로 단백질을 동정한 결과 동정된 10종의 단백질 중 8종의 단백질은 당의 대사와 관련된 효소들 임을 확인하였다.

• Korean Chemical Engineering Research
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• 제50권1호
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• pp.141-148
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• 2012

바이오에탄올 생산을 위한 대체 바이오매스 자원으로 갈조류인 다시마의 활용 가능성을 평가하기 위하여 산 가수분해와 에탄올 발효 특성을 검토하였다. 산 가수분해는 발효 가능한 당류의 생산량을 증가시켜 에탄올 생산량을 크게 증가시켰다. 최대 환원당 생산량은 묽은 황산(1.0 N)을 이용하여 $130^{\circ}C$에서 6시간 가수분해하는 조건에서 다시마 건조무게 기준 135 mg/g이었다. Saccharomyces cerevisiae(ATCC 24858)는 글루코오스, 갈락토오스 및 만노오스와 같은 $C_6$-당을 에탄올로 발효시킬 수 있지만 아라비노오스나 자일로오스와 같은 $C_5$-당은 에탄올 발효기질로 이용하지 못하였다. 최적 발효시간은 글루코오스 48시간, 갈락토오스 72시간, 만노오스 96시간으로 단당류에 따라 달랐다. 그럼에도 불구하고 S. cerevisiae를 이용하여 $35^{\circ}C$에서 96시간 발효를 통해 가수분해물로부터 얻을 수 있는 에탄올 생산량은 가수분해물 중의 총환원당으로부터 얻을 수 있는 이론적 생산량에 비해 4배 정도 높은 다시마 건조무게 기준 242 mg/g에 달하였다. 이는 가수분해물에 용존되어 있는 비환원당과 올리고당류들이 에탄올 발효에서 중요한 역할을 하고 있음을 나타낸다. 가수분해 용액 대비 다시마의 주입비율을 1에서 5%(w/v)로 증가시킴에 따라 에탄올 농도는 2.4에서 9.2 g/L로 증가하는 반면 단위무게당 에탄올 생산량은 242에서 185 mg/g으로 감소하였다. 다시마의 에탄올 생산성은 대략 7,400~9,600 kg/ha/year 정도로 평가되어 다시마가 바이오에탄올 생산을 위한 바이오매스 자원으로 매우 유용함을 알 수 있었다.

• 한국식품과학회지
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• 제27권1호
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• pp.36-40
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• 1995

한국산 마의 주요 품종인 D. batatas, D. aimadoimo 및 D. japonica 등 3가지 품종의 일반성분을 분석하여 비교하였고 각 시료들을 동결건조하여 분말로 만든 다음 분획하여 HPLC에 의한 탄수화물의 조성과 함량, DNS법에 의한 환원당을 정량하였다. 탄수화물 중 유리당을 구성하는 주된 조성은 fructose, glucose, sucrose 및 maltose 등이었고 이 중 D. batatas에서는 glucose와 sucrose, D. aimadoimo와 D. japonica에서는 fructose와 sucrose가 가장 많은 부분을 차지하고 있었다. 총당은 주로 mannose와 glucose로 구성 되었고 3가지 품종 모두 mannose가 80% 이상으로, 이는 마가 감자나 고구마보다 끈끈한 점질물로 알려진 mannan이 많기 때문인 것으로 생각된다. Soluble fraction과 전체 마에서의 환원당 정량결과 soluble fraction에서 당함량은 D. aimadoimo가 가장 많았고, insoluble fraction에서 당함량은 D. japonica가 가장 많았다.

• 미생물학회지
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• 제25권4호
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• pp.360-366
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• 1987

For the production of pullulan from the high concentration of sugar, the utilization of sugars by a pullulan-producing fungus, Aureobasidium pullulans was examined. A. pullulans showed the different utilization patterns for sugars such as sucrose, maltose, and maltotriose. Especially for maltotriose, the hydrolysis of sugar was accompanied by a transferase activity. Glucose and maltose showed the inhibitory effect on the cell growth and the pullulan production at the sugar concentration higher than 0.28M, but sucrose showed the inhibitory effect at the sugar concentration higher than 0.14M. Among the sugars examined, sucrose gave the best result for the pullulan production. 27.5g/l of pullulan was obtained from 5% sucrose.

• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.663-671
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• 2022

The saccharification of cellulose and hemicellulose is essential for utilizing lignocellulosic biomass as a biofuel. While cellulose is composed of glucose only, hemicelluloses are composed of diverse sugars such as xylose, arabinose, glucose, and galactose. Sulfolobus acidocaldarius is a good potential candidate for biofuel production using hemicellulose as this archaeon simultaneously utilizes various sugars. However, S. acidocaldarius has to be manipulated because the enzyme that breaks down hemicellulose is not present in this species. Here, we engineered S. acidocaldarius to utilize xylan as a carbon source by introducing xylanase and β-xylosidase. Heterologous expression of β-xylosidase enhanced the organism's degradability and utilization of xylooligosaccharides (XOS), but the mutant still failed to grow when xylan was provided as a carbon source. S. acidocaldarius exhibited the ability to degrade xylan into XOS when xylanase was introduced, but no further degradation proceeded after this sole reaction. Following cell growth and enzyme reaction, S. acidocaldarius successfully utilized xylan in the synergy between xylanase and β-xylosidase.

• 대한영양사협회학술지
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• 제24권1호
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• pp.62-74
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• 2018

The purpose of this study was to investigate dietitians or nutrition teachers' perception of sugar reduction and usage of sugars in school meal service. A survey was conducted for dietitians or nutrition teachers at elementary, middle, and high schools in Gyeonggi and Incheon. Survey data were analyzed according to the experience period and school types of dietitians or nutrition teachers. The numbers of subjects according to work experience period were 134 (44.2%) for <5 years, 68 (22.4%) for ${\geq}5$ and <10 years, and 101 (33.3%) for ${\geq}10years$. Among the subjects, 168 (55.4%) were nutrition teachers at kindergarten/elementary schools, and 135 (44.6%) were at middle/high/special schools. Perceptions of sugar reduction programs were higher in kindergarten/elementary schools than in middle/high/special schools. The perception of added sugar use increased with more work experience, and interest in sugar reduction was higher in kindergarten/elementary schools than in middle/high/special schools. Practice for added sugar reduction increased with more work experience, and the most common method for reducing sugar was use of natural sugars. The main reason for not reducing added sugars in school meals was due to preference. Nutritional education for students increased with more work experience and was higher in kindergarten/elementary schools than in middle/high/special schools. The major nutritional education methods were using school homepage (37.4%), sending family letters (37.4%), and using principle's discretion time (18.4%). Organic sugar and rice taffy were used more at kindergarten/elementary schools, and white sugar, brown sugar, and white syrup were used more at middle/high/special schools. The most common menu using added sugars was stir-fried dishes (stir-fried pork, chicken, and vegetables).