• Journal of the East Asian Society of Dietary Life
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• v.1 no.1
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• pp.99-111
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• 1991

In each nuruk using today, effect of pH on glucoamylase activity and viable cell count of yeast and bacteria was measured. Common components during fermentation, alcohol, acetaldehyde and acetone, amino acid composition, and total sugars and mineral content were determined in yakju(korean wine) brewed from different ingredients and by different methods. Results are summarized as follows ; 1. The lower the pH, the lower the glucoamylase activity in JK, BK, JK-S BK-S and JN. But the higher the glucoamylase activity ratio in Koji and KN. 2. Yeast and bacteria cell count could not determined in nuruk inoculated of seed. In JK, BK and JN, yeast cell count was 50${\times}$104∼80${\times}$104, bacteria cell count was 5${\times}$106∼24${\times}$106. 3. In yakju during fermentation, pH was higher in RU, total acidity content was higher in ST-N, ST-K, RU and ST-RUPO and alcohol content was lower in RUPO and ST-RUPO. 4. Ethanol and acetaldehyde content were highest in dukyunju. Trace amount of acetone was determined only in ST-K, RUPO and ST-RUPO . n-Propyl alcohol content was higher in ST-K, ST-RUPO and ST-N, iso-butyl alcohol content was higher in L-RUPO, Dukyunju and Songyupju and iso-amyl alcohol content was higher in Songyupju, RU, L-RUPO and Dukyunju. 5. In amino acids composition of each yakju, Pro, Ala and Val content was higher than other amino acids. Total amino acids content was the highest in Dukyunju and second highest in ST-N, NH3 was higher in ST-N, Dukyunju, RUPO than other samples. 6. Total sugars content was the highest in ST-N and second highest in RU. 7. P, K and Mg content were higher in Dukyunju and ST-N than in other samples. In Dukyunju, Ca and P ratio was 0.075 because of low Ca content and high P content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.801-804
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• 1999

Quality characteristics of yakju prepared by different yeast strains such as Saccharomyces cerevisiae S 2, Saccharomyces cerevisiae S 6 and Saccharomyces cerevisiae IFO 1950 were investigated during fermentation. The pH in all kinds of yakju was gradually decreased until 6 days and then it was constant. In stage of fermentation, acidity of yakju made of Saccharomyces cerevisiae S 6 was higher than others. At the beginning stage of fermentation, ethanol contents were in the range of 0~2% increased to 9.5~11.5% after 10 days. Yakju made of Saccharomyces cerevisiae S-2 showed higher ethanol contents than others. Free sugars in yakju were found to be glucose and maltose. The contents of free sugars were decreased until 6 days and they were not detected. The content of ethanol in yakju showed the highest value at the 6th day and those of yakju A, B and C were 11.9, 9.5, 10.9%, respectively. Main organic acids in yakju were citric acid and lactic acid. The content of citric acid in yakju B was higher than others.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.22-27
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• 2006

Contents of free sugars and sorbitol and their distributional profiles in Tsugaru, Fuji, Jonathan (Hong-Ok), and New Jonagold (Sin-Heung) apple cultivars were evaluated. Average total sugar contents of Tsugaru, Fuji, Jonathan, and New Jonagold were 9.62, 11.79, 11.20, and 10.28%, respectively. HPLC results showed sucrose, glucose, fructose, and sorbitol contents of apples ranged 0.72-3.26, 1.81-3.16, 5.08-6.96, and 0.22-0.96%, respectively. Ratios of individual sugar and sorbitol to sum of fructose, glucose, sucrose, and sorbitol (TS+S) were estimated for all apples. Fructose/TS+S and glucose/TS+S ratios did not differ significantly among cultivars, whereas sucrose/TS+S and sorbitol/TS+S ratios varied. Fructose/glucose ratios were 2.295, 2.244, 2.161, and 2.393 for Tsugaru, Fuji, Jonathan, and New Jonagold, respectively.

• Korean Journal of Pharmacognosy
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• v.9 no.2
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• pp.83-88
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• 1978

From phytochemical screening of the seven species of Caryophyllaceae, that is, one species of Melandrium, and Dianthus and Pseudostellaria, two species of Stellaria and Cerastium the following compounds were identified. 1) aldehyde, sugars, other reducing compounds and glycosides from the above mentioned seven species of Caryophyllaceae were identified by thin layer chromatography method and comparison of Rf values with the standard substances. 2) Saponins, steroids and terpenoids showed positive reaction with the Froth testing in all of seven plants. Five species of plant showed positive reaction with Liebermann-Buchard test. 3) Flavonoid and polyphenolic compounds were identified by the spots in TLC-test and chlorogenic acid showed the same Rf values with the standard substances. 4) The spots of alkaloid were shown at Rf=0.68 (Stellaria aquatica) and at Rf=0.71 (Pseudostellaria palibiniana) and at Rf=0.70, and 0.44 (Dianthus sinensis).

• Journal of Sensor Science and Technology
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• v.22 no.4
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• pp.281-285
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• 2013

In this study a biosensor was developed by using Drosophila cells expressing a gustatory receptor Gr5a and an ion sensitive field effect transistors (ISFETs) sensor device, which demonstrated significant compatibility with the Drosophila cells expressing Gr5a and their response to sugar. These results suggested that the newly developed cell based biosensor has a potential as a simple and easy screening device for Alzheimer's disease in the future.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.107-113
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• 2022

A number of studies have been conducted to confirm the preventive effect of xylitol on dental caries as a whole or partial alternative to dietary sugars. This study reviewed the oral health effects of xylitol on the prevention mechanism of dental caries, the prevention of dental caries, the inhibition of mother-to-child transmission, and the oral health effects in the elderly based on existing studies on the oral health of xylitol. Carbohydrates and dietary sugars in food are fermented by acid-producing microorganisms in the mouth and produce dental plaque and acid, which cause dental caries. However, most dental decay-causing bacteria cannot produce acids by metabolizing xylitol. Xylitol, stored in cells as a non-metabolizable metabolite by Streptococcus mutans (S. mutans), affects bacterial glucose metabolism and inhibits bacterial growth. Xylitol consumption also reduces the amount of plaque and the population of S. mutans in both plaque and saliva. In addition, xylitol acts in the remineralization process. Xylitol has been confirmed to effectively prevent dental caries, inhibit mother-to-child transmission of MS, prevent dental caries, and increase salivary flow in the elderly. In conclusion, xylitol is an adequate sugar substitute for dental health, from infants to the elderly. For future studies, the researchers recommend reviewing the effects of xylitol on the oral and intestinal microbial environment and the side effects of excessive intake.

• Food Science and Preservation
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• v.23 no.6
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• pp.866-875
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• 2016

In this study, we investigated the variation in free sugars, amino acids, antioxidant activity, and anti-inflammatory activity of Solanum nigrum Linne based on harvest time. Major amino acids identified by HPLC analysis were proline, histidine, and serine. The highest content of total amino acids were found in S. nigrum aerial parts and roots harvested on July 10th and August 10th. Four kinds of free sugars (fructose, glucose, sucrose, maltose) were detected in S. nigrum, and the free sugar content varied significantly with harvest time. The fructose content of S. nigrum decreased with as harvest time increased. The total polyphenol content of S. nigrum was highest in those harvested on August 30th. The antioxidant activity of ethanol extract from S. nigrum collected at different harvest times were measured by DPPH and ABTS radical scavenging assays. The anti-inflammatory activity of these extracts were assayed via nitric oxide suppression in C6 glioma cells with a lipopolysaccharide (LPS)-induced inflammatory response. The anti-inflammatory activity and antioxidant effects were the highest in the extract from S. nigrum collected on August 30th. Good correlations were observed between antioxidant and anti-inflammatory activities in ethanol extract of S. nigrum roots harvested on August 30th.

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.278-285
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• 2010

We examined the distribution of exopolysaccharide (EPS) producing bacteria population in rhizosphere soils of domestic medicinal herbs; Angelica sinensis, Atractytodes japonica, Achyranthes japonica, Anemarrhena asphodeloides, and Astragalus membranaceus. Fifty-six percent of the total isolates from rhizosphere soil of Angelica sinensis were EPS producing bacteria, suggesting the dominance of EPS producing bacteria in rhizosphere soil of Angelica sinensis. EPS producing bacteria were enumerated in root system (rhizosphere soil, rhizoplane, inside of root) of Angelica sinensis. Bacterial density of rhizosphere soil, rhizoplane, and inside of root were distributed $9.0{\times}10^6CFU/g{\cdot}soil$, $7.0{\times}10^6CFU/g{\cdot}soil$, and $1.4{\times}10^3CFU/g{\cdot}soil$, respectively. EPS producing bacteria from rhizosphere soil were categorized into five major phylogenetic groups: Alphaproteobacteria (4 strains), Betaproteobacteria (6 strains), Firmicutes (2 strains), Actinobacteria (3 strains), and Bacteroidetes (1 strain) subdivisions. Also, the EPS producing isolates from rhizoplane were distributed as 7 strains in Alphaproteobacteria, 3 strains in Betaproteobacteria, 2 strains in Actinobacteria, 3 strains in Bacteroidetes, and 1 strain in Acidobacteria subdivisions. All of the EPS producing bacteria inside of root belong to genus Chitinophaga. Burkholderia caribiensis DR14, Terriglobus sp. DRP35, and Rhizobium hainanense SAP110 were selected in 112 EPS producing bacteria. These appeared to have produced high levels of exopolysaccharide 6,555 mpa.s, 3,275 mpa.s, and 1,873 mpa.s, respectively. The purified EPS was analyzed Bio-LC. As neutral sugars, glucose, galactose, mannose were detected and as amino sugars, galactosamine and glucosamine were detected. Especilally, analysis of Bio-LC showed that Rhizobium hainanense SAP110 produced glucose (60~89%) and glucosamine (8.5%) as major neutral sugar and amino sugar, respectively.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.849-857
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• 2016

In the growth of the Rubus coreanus Miquel fruits, the unripened (10 days) and ripened (25 days) fruits after flowering were harvested. The chemical characteristics of different maturational stages of the unripened and ripened fruits were investigated. Total amount of phenolic compounds was 4.00-7.56% in the unripened fruits and 3.78-5.57% in the ripened fruits, respectively. Furthermore, total amounts of organic acids such as malic, citric, succinic, and oxalic acids were 16.40 mg/100 g in the unripened fruits and 28.82 mg/100 g in the ripened fruits, respectively. In organic acids of the unripened and the ripened fruits, citric acid (8.76-15.47 mg/100 g) was the highest amount among other organic acids. Soluble sugars were significantly increased from 11.07 to 21.54% in the unripened and ripened fruits. Therefore, ripened fruits had the high levels of phenolic compounds, organic acids and soluble sugars. For the biological studies of R. coreanus, methanol extracts of R. coreanus leaves, fruits, and stems were evaluated for their insecticidal activities against Myzus persicae (Hemiptera: Aphididae), Plutella xylostella (Lepioptera: Plutellidae) and Spodoptera litura (Lepioptera: Noctuidae) by leaf dipping method. From these results, the extract of R. coreanus leaves revealed potent insecticidal activity against P. xylostella. However, the methanol extracts of R. coreanus fruits and stems had no any insecticidal activity against M. persicae, P. xylostella and S. litura. The R. coreanus leaves have promising potential as new insecticidal agent against P. xylostella.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.229-235
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• 1997

The chemical components of 5 domestic wheats(Kru, Suwon 257, Eunpa, Chokwang and Tapdong), Australian standard white wheat(ASW) and dark northern spring wheat(DNS) were determined in terms of amino acids, sugars and minerals for whole wheat and white wheat flour of 70% milling yield. The protein content of whole Eunpa and Tapdong was approximately 15%, and reduced its content approximately 1% after milling compared to that of whole wheats. The high levels of glutamic acid and proline were observed in domestic wheats. The limiting amino acid of domestic wheat was higher than that of ASW, but lower than that of DNS. Especially, Suwon 257 and Tapdong exhibited the higher limiting amino acid content than other domestic wheats. Glutamic acid and proline content increased, while lysine and threonine was decreased after milling. In general, whole wheat exhibited the higher levels of arabinose and xylose, and the lower level of glucose than flour. The results also showed domestic wheat contained the higher amount of arabinose and xylose than the foreign wheats. Domestic wheat and flour possessed the higher amount of mineral such as P, K, Na and Ca than ASW and DNS, while Al and Si were similar to others.