• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.822-832
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• 2017

This study analyzed contents of organic acids, free sugars, and volatile flavor compounds by type of Jerusalem artichoke (Helianthus tuberosus L.). Organic acids in dried Jerusalem artichoke were mainly composed of malic acid, citric acid, and succinic acid. Sucrose, fructose, and glucose were the major sugar components of dried Jerusalem artichoke. Free sugars were more abundant in the white colored sample than in the purple colored sample. In contrast, purple colored sample contained more organic acids than the white colored one. Volatile compounds in Jerusalem artichoke were investigated using the solid-phase micro-extraction method of gas chromatography/mass spectrometry. A total of 117 volatile compounds were identified in Jerusalem artichoke, and chemical classification was as follows: 5 acids, 13 alcohols, 19 aldehydes, 12 hydrocarbons, 15 ketones, 8 miscellaneous, 27 pyrazines, and 18 terpenes in all samples. Terpene was the most abundant in Jerusalem artichoke, and ${\beta}$-bisabolene was the main component in terpenes. The second most common compound was aldehyde, and hexanal was the highest. Pyrazines were the most abundant in the roasted samples, and 2,5-dimethyl-3-ethylpyrazine was present at the highest level, followed by 2,5-dimethylpyrazine. Compared with purple samples, main compounds contained in white samples were aldehydes and hydrocarbons, whereas the major compounds in purple samples were terpenes and alcohols.

• Clean Technology
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• v.28 no.3
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• pp.232-237
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• 2022

Biorefineries, in which renewable resources are utilized, are an eco-friendly alternative based on biomass feedstocks. Alginic acid, a major component of brown algae, which is a type of marine biomass, is widely used in various industries and can be converted into value-added chemicals such as sugars, sugar alcohols, furans, and organic acids via catalytic hydrothermal decomposition under certain conditions. In this study, ruthenium-supported activated carbon and magnesium oxide were mixed and applied to the depolymerization of alginic acid in a batch reactor. The addition of magnesium oxide as a basic promoter had a strong influence on product distribution. In this heterogeneous catalytic system, the separation and purification processes are also simplified. After the reaction, low molecular weight alcohols and organic acids with 5 or fewer carbons were produced. Specifically, under the optimal reaction conditions of 30 mL of 1 wt% alginic acid aqueous solution, 100 mg of ruthenium-supported activated carbon, 100 mg of magnesium oxide, 210 ℃ of reaction temperature, and 1 h of reaction time, total carbon yields of 29.8% for alcohols and 43.8% for a liquid product were obtained. Hence, it is suggested that this catalytic system results in the enhanced hydrogenolysis of alginic acid to value-added chemicals.

• Korean journal of food and cookery science
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• v.19 no.1
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• pp.1-10
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• 2003

All optional ingredient, Jasoja(Perillae semen) was adopted to improve Dongchimi in qualify during fermentation. Free sugar, free amino acid, non-volatile organic acid and volatile compounds were determined during fermentation at 10$^{\circ}C$ for 45 days. Free sugar content was slightly higher in 0.5%-Jasoja-treated samples than that of control. The contents of free amino acids in control Dongchimi (without jasoja) increased slowly during fermentation while those in 0.5 %-treated samples began to decrease after reaching their maximum value on the day 11 when Dongchimi became most acceptable. There were 6 non-volatile organic acids, such as lactic, fumaric, succinic, malic, tartaric, and citric acid. Among these, only lactic and succinic acid increased consistently with fermentation while others decreased. Volatile components in Dongchimi were mostly identified as sulfur-containing compounds by gas chromatography. Their numbers and % peak areas in the gas chromatogram decreased slightly with the increase in organic acids and alcohols during fermentation period. On the other hand, Dongchimi prepared with Jasoja maintained its contents of total acids as well as the level of sulfur-containing compounds.

• Food Science and Preservation
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• v.12 no.4
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• pp.402-410
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• 2005

In order to manufacture the alcoholic drinks using cultured wild ginseng roots(CWGR) of 5 and $10\%$ (w/v), sugar content of fermentation media was adjusted to 24-25 $^{\circ}$Brix with white sugar and glucose. And 3 kinds of yeast (S. cerevisiae(KCCM 50757), S. cerevisiae (KCCM 50583) and S. bayanus(ATCC 10601) were used and then the quality of alcoholic drinks was analyzed by physical, chemical and sensory evaluation. Alcohol content was highest value of $15.8\%$ in $10\%$ of CWGR, white sugar, and S. bayanus(ATCC 10601). Major alcohols were ethanol and 1-propanol. Number of yeast cells increased to 5 days fermentation and slightly decreased afterwards. The pH was decreased abruptly from 5.0 in initial fermentation to 3.1-4.1 in 5 days fermentation. Total sugar contents were decreased continuously with fermentation periods and showed 7.0-10.5 $^{\circ}$Brix in 20 days fermentation. Saponin patterns and contents were various and higher in wine treated with S. bayanus(ATCC 10601). From the sensory evaluation, the highest score of overall quality was observed in the alcoholic beverage of $10\%$(w/v) of CWGR, glucose, and S. cerevisiae(KCCM 50583).

• Plant Biotechnology Reports
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• v.2 no.3
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• pp.179-189
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• 2008

We established an efficient plant regeneration system for Catharanthus roseus L. (G.) Don through somatic embryogenesis. Embryogenic callus was induced from hypocotyl of seed germinated in vitro. Somatic embryogenesis in Catharanthus has been categorized into three distinct stages: (1) initiation and proliferation of embryo; (2) maturation, and; (3) germination or plantlet conversion. Beside plant growth regulators, various stages of embryogenesis were screened for their response to a wide variety of factors (pH, gelrite, light, sugar alcohols, polyethyleneglycol and amino acids), which affect embryogenesis. All of the tested factors had a small to marked influence on embryogeny and eventual conversion to plantlets. The plantlets were acclimatized successfully in a greenhouse. To our knowledge, this is the first report describing a detailed study of various cultural factors which regulate embryogenesis in C. roseus. The results discussed in this paper may be used in mass propagation to produce medicinal raw material, and the embryo precursor cells could be used in genetic modification programmes that aim to improve the alkaloid yield as well.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.99-104
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• 2005

Microbacterium laevaniformans levansucrase synthesized various hetero-oligosaccharides by transferring fructosyl residue from sucrose to various saccharides as acceptors. The acceptor specificity test showed that reducing saccharides were more favorable acceptors than nonreducing saccharides. The transfructosylated product, fructosyl galactose, was produced in the presence of D-galactose as an acceptor. The chemical structure of the resulting fructosyl galactose was analyzed by yeast invertase and NMR, and identified as O-$\alpha$-D-galactosyl-(1${\to}$2)-$\beta$-D-fructofuranoside. These results indicate that the main transfructosylation activity of the enzyme is to make nonreducing transferred products via a transfer of fructosyl residue to acceptor molecules having reducing group. When nonreducing sugars, such as methyl $\alpha$-D-glucoside and methyl $\alpha$-D-galactoside, were used as an acceptor, the transfer product was also formed in spite of the reducing group blocked with methyl group. The fact that no transfer product was formed with sugar alcohols as acceptors was suggested to be due to marked conformational difference of acceptors.

• Mycobiology
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• v.42 no.4
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• pp.353-360
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• 2014

Makgeolli is a traditional Korean alcoholic beverage. The flavor of makgeolli is primarily determined by metabolic products such as free sugars, amino acids, organic acids, and aromatic compounds, which are produced during the fermentation of raw materials by molds and yeasts present in nuruk, a Korean fermentation starter. In this study, makgeolli was brewed using the wild yeast strain Saccharomyces cerevisiae Y98-5, and temporal changes in the metabolites during fermentation were analyzed by ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. The resultant data were analyzed by partial least squares-discriminant analysis (PLS-DA). Various metabolites, including amino acids, organic acids, sugar alcohols, small peptides, and nucleosides, were obviously altered by increasing the fermentation period. Changes in these metabolites allowed us to distinguish among makgeolli samples with different fermentation periods (1, 2, 3, 6, 7, and 8 days) on a PLS-DA score plot. In the makgeolli brewed in this study, the amounts of tyrosine ($463.13{\mu}g/mL$) and leucine ($362.77{\mu}g/mL$) were high. Therefore, our results indicate that monitoring the changes in metabolites during makgeolli fermentation might be important for brewing makgeolli with good nutritional quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.572-578
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• 1999

This study was conducted to investigate processing condition and characteristics of chestnut paste. The kinds of chestnut powder processed with blanching and drying of raw material were four named RH(not blanched, hot air dried), RF(not blanched, freeze dried), BH(blanched, hot air dried) and BF(blanched, freeze dried). Blanching affected the reduction of drying time in chestnut. Water absorption index of the blanched samples were higher than the nonblanched. Blanching affected the viscosity of pastes when water was added to process paste also, but drying methods did not affected to it. The proper ratio of water to the powder to process paste was 1.3 to 1.5 times in RH and RF, whereas 2.7 times in BH and BF by sensory evaluation. Soluble tannin content of paste was higher in RF and RH paste than BF and BH. Vitamin C content was the highest(88.49mg/100g) in RF paste and reducing sugar content was the highest in RF paste. Hunter's L and a values were the highest in BF and RH pastes, respectively, among the all paste samples. Volatile compounds detected from chestnutpastes were hydrocarbons, alcohols, phenols, ketones. The major volatile compound in all the pastes was 2,6 bis(1,1 dimethylethyl) 4 methyl phenol.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.2
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• pp.109-116
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• 1988

Oriental tobacco (KA 101) was transplanted from Mar. 25 to May 5 with 10 days interval in 1984 and 1985, and its agronomic characteristics, chemical properties ware compared to determine the Proper transplanting time of aromatic tobacco In Korea. As the transplanting was delayed, days to flowering of plant was shortened, length and width of largest leaf, leaf area index tended to decrease. Yield was highest for the Apr. 5th transplanting followed by Mar. 25th planting, then decreased as the planting date was delayed. Quality by price decreased as the transplanting was delayed later than Apr. 25. Delaying transplanting increased nicotine, total nitrogen and ash content, but decreased reducing sugar and petroleum ether extract of cured leaves, The content of volatile organic acids such as 3-methyl pentanoic acid was lower when it was transplanted later than Apr. 25th. Neophytadiene content increased as the transplanting was delayed, but there were no trends with the content of alcohols, aldehydes esters and ketones. Several quality indices including the ratio between the content of volatile organic acids plus petroleum ether extract and ash content plus pH was higher for the Apr. 5th transplanting.

• Mycobiology
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• v.50 no.2
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• pp.110-120
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• 2022

The goal of the present study was to investigate the antibacterial properties, enzyme production, and metabolic profiling of a new Ceratorhiza hydrophila strain isolated from the submerged aquatic plant Myriophyllum spicatum. Furthermore, the fungus' morphological characterization and DNA sequencing have been described. The fungus has been identified and submitted to the GenBank as Ceratorhiza hydrophila isolate EG19 and the fungus ID is MK387081. The enzyme analyses showed its ability to produce protease and cellulase enzymes. According to the CSLI standard, the ethyl acetate extract of C. hydrophila showed intermediate antibacterial activity against Streptococcus pneumonia, Micrococcus luteus, and Staphylococcus aureus. Metabolic profiling has been carried out using 700 MHz NMR spectroscopy. Based on the ¹H and ¹H-¹³C heteronuclear single quantum coherence (HSQC) NMR data and NMR databases, 23 compounds have been identified. The identified metabolites include 31% amino acids, 9% sugars, 9% amines, 4% sugar alcohols, and 4% alkaloids. This is the first report for the metabolic characterization of C. hydrophila, which gave preliminary information about the fungus. It is expected that our findings not only will pave the way to other perspectives in enormous applications using C. hydrophila as a new promising source of antimicrobial agents and essential metabolites, but also it will be valuable in the classification and chemotaxonomy of the species.