• Mycobiology
• /
• v.42 no.4
• /
• pp.353-360
• /
• 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 Magnetic Resonance Society
• /
• v.21 no.2
• /
• pp.44-49
• /
• 2017

Coffee is one of the top selling products in the world. There are various coffee bean species around the world. Among them, Coffea Arabica is the most popular species. However, there are few studies on the metabolites of coffee beans so far. This study demonstrates effects of the planted regions on the metabolite concentrations of coffee beans. The metabolites of coffee beans can be affected by growing area even although same species are grown. Accordingly, we studied coffee bean metabolites extracted from the same species in different regions (The brand names, Kona from Hawaii, Mocha Matari from Yemen, and Blue Mountain from Jamaica) by using mixed solvent of methanol: water: chloroform. A comparative analysis by NMR spectroscopy was performed and the statistical techniques were used to figure out the differences. As a result, we found that chlorogenic acid, caffeine, citrate, and sucrose mainly contributed to the separation of the three groups. When compared with Kona and Blue Mountain, concentrations of chlorogenic acid, caffeine, and sucrose in Mocha Matari were observed to be relatively down-regulated. In addition, compared with the two other groups, concentration of citrate in Kona was observed to be up-regulated.

• Korean Journal of Agricultural Science
• /
• v.49 no.2
• /
• pp.331-339
• /
• 2022

Deforestation and conservation of coniferous forest have been recognized as critical issues in Korea due to climate change. The main purpose of this research was to monitor changes of secondary metabolite contents and growth of Korean fir (Abies koreana) according to the temperature change in Mt. Halla. The Korean fir located at three different regions, Yeongsil, Witseoreum, and Jindallaebat, was monitored in April, July, and October from 2016 to 2018 and secondary metabolites, specifically lutein, α-carotenoid, and β-carotenoid, were analysed with high performance liquid chromatography. The results showed that average concentrations of lutein, α-carotenoid, and β-carotenoid were 0.82 - 23.30, 0.02 - 2.01, and 0.11 - 2.84 ㎍·g-1 and the highest concentration of secondary metabolite was observed in October compared to April and July. The average length and width of Korean fir in the three regions were 11.84 - 20.70 and 1.78 - 2.41 mm from 2016 - 2018. A correlation analysis showed that the concentrations of all three secondary metabolites were negatively correlated with temperature and a significant difference was observed between temperature and lutein concentration in Korean fir. Overall, growth and production of secondary metabolites in Korean fir highly depended on the temperature, and global warming thus might have an adverse effect on the growth and physiological changes of Korean fir in Mt. Halla.

• Journal of Wetlands Research
• /
• v.9 no.1
• /
• pp.99-105
• /
• 2007

Nonylphenol polyetoxylates (NPnEOs) metabolites; nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenoxyacetic acid (NPEC) (collectively referred to "NPE-c") were examined for their degradations by using of lab-scale UV/photocatalytic silicagel (ultraviolet photocatalytic degradation in the presence of silicagel coated with titanium dioxide as a catalyst) reactor. NPE-c degradations by UV/photocatalytic silicagel treatment reached approximately 85-93 % after 40 min irradiation independently of its initial concentration (between ca. 0.5 and 2.0mg/l). Any intermediates under the NPE-c degradation were not identified by GC/MS sample analysis. Degradations of NPE-c were followed pseudo first-order kinetics. Then, the effectiveness of UV/photocatalytic silicagel treatment for degradation of NPE-c was in the order of NPEC > NP > NP1EO.

• 한국균학회소식:학술대회논문집
• /
• 2018.05a
• /
• pp.49-49
• /
• 2018

A variety of bioactive secondary metabolites have been reported from plant-associated microorganisms. Halophytes, plants that can only grow in hypersaline area, were reported to host beneficial microorganisms such as plant growth-promoting endophytes. The microorganisms have been reported to show notable mutualistic symbiosis with halophytes to help them survive in high saline condition. Finding out bioactive secondary metabolites as well as elucidation of relationship(s) between microbes and the host halophyte has been paid attention, because of their functional diversity. Novel microbes often have associated with novel natural products. In an effort to investigate natural compounds with interesting structures from fungi, we selected plants from a distinct environmental setting which could be a promising source. Several fungi were isolated from halophyte or medicinal plants. Some strains of the fungi were cultivated on a large scale and extracted with ethyl acetate, which were subjected to a series of chromatographic methods, leading to the isolation of tens of compounds. The isolated compounds were identified by analysis of spectroscopic methods such as 1D-, 2D-NMR, and MS. Details of isolation, structure determination, and biological activities will be discussed.

• ALGAE
• /
• v.33 no.3
• /
• pp.205-214
• /
• 2018

Red algae in the genus Portieria produce secondary halogenated monoterpenes, which are effective deterrents against herbivores, as secondary metabolites. Portieria hornemannii samples from various sites contain different concentrations of these metabolites, suggesting the existence of genetic diversity and cryptic species. To evaluate the genetic diversity and species distribution of Portieria in the northwest Pacific, we analyzed rbcL sequences of samples collected from Korea, Japan, and Taiwan. The phylogenetic analysis revealed five distinct lineages at the species level. One was recognized as Portieria japonica and the others were cryptic lineages in P. hornemannii. The rbcL haplotypes of P. japonica were genetically fragmented into two subgroups of geographic origin; Korean and Japanese. The four cryptic lineages within P. hornemannii were also geographically structured at a much finer scale. These results suggest that different genetic lineages in Portieria evolved from variable microhabitats, consequently influencing secondary metabolites. Further study is required to resolve the relationships between genetic and secondary metabolite variations in Portieria.

• Journal of the Korean Magnetic Resonance Society
• /
• v.8 no.2
• /
• pp.115-126
• /
• 2004

Four secondary metabolites from an unidentified tunicate were isolated by treatment with trichloroethyl chloroformate(TECF) or acetic anhydride in pyridine. Their structures were determined by an extensive NMR analysis and the configuration of diacetyl derivatives(3a, 4a) was assigned by comparing with NMR data of a similar compound. Three new naturally occurring compounds (1, 3, 4) showed potent brine shrimp lethality and antifungal effect against Candia albicans.

• Journal of Pharmaceutical Investigation
• /
• v.40 no.3
• /
• pp.155-160
• /
• 2010

A gas chromatographic-mass spectrometric (GC-MS) method was developed for the simultaneous determination of valproic acid (VPA) and its toxic metabolites, 4-ene-VPA and 2,4-diene-VPA in rat plasma. Extraction was performed in weak acidic condition (pH 5.2) to avoid degradation of 4-ene-VPA and 2,4-diene-VPA. The recoveries for 4-ene-VPA and 2,4-diene-VPA were more than 70% and that for VPA was 33-42%. R value for each compounds exceeded 0.998 in calibration curve during all the analysis. Accuracy and precision ranged from 88.3 to 113.2% and from 2.16 to 14.2%, respectively The method was successfully applied to monitor plasma concentrations of VPA, 4-ene-VPA and 2,4-diene-VPA after intravenous administration of VPA at the dose of 100 mg/kg, suggesting that these toxic metabolites may involved in the hepatotoxicity induced by VPA.

• Biomolecules & Therapeutics
• /
• v.19 no.2
• /
• pp.149-154
• /
• 2011

Matrix assisted laser desorption ionization (MALDI) mass spectrometry is commonly used to analyze biological molecules such as proteins, peptides and lipids from cells or tissue. Recently MALDI Imaging mass spectrometry (IMS) has been widely applied for the identification of different drugs and their metabolites in tissue. This special feature has made MALDI-MS a common choice for investigation of the molecular histology of pathological samples as well as an important alternative to other conventional imaging methods. The basic advantages of MALDI-IMS are its simple technique, rapid acquisition, increased sensitivity and most prominently, its capacity for direct tissue analysis without prior sample preparation. Moreover, with ms/ms analysis, it is possible to acquire structural information of known or unknown analytes directly from tissue sections. In recent years, MALDI-IMS has made enormous advances in the pathological field. Indeed, it is now possible to identify various changes in biological components due to disease states directly on tissue as well as to analyze the effect of treated drugs. In this review, we focus on the advantages of MALDI tissue imaging over traditional methods and highlight some motivating findings that are significant in pathological studies.

• Journal of Plant Biotechnology
• /
• v.49 no.3
• /
• pp.230-239
• /
• 2022

Holostemma annulare (Family Asclepiadaceae) is an invaluable vulnerable medicinal plant; the root tubers are used in Ayurveda medicine and by folk healers to treat various ailments. In this study, Schenk and Hildebrandt medium fortified with the cytokinins 6-benzyl adenine, kinetin, and auxins, including indole 3-butyric acid, indole 3-acetic acid, α-naphthaleneacetic acid, and 2,4-dichlorophenoxyacetic acid, were checked for their efficiency on root tuber induction from different explants. Adventitious root tubers were more successfully induced from in vitro leaf segments and shoots when cultured in Schenk and Hildebrandt medium supplemented with 0.5 mg/l of α-naphthaleneacetic acid. In addition, preliminary phytochemical analysis of in vitro root tubers and identification of different secondary metabolites were conducted. Thin layer chromatography and high performance thin layer chromatography analysis of the crude methanolic extracts of the in vitro root tuber identified the presence of lupeol, a bioactive triterpene. Adventitious root tuber induction offers a novel method for the in vitro production of bioactive metabolites that can be scaled up by bioreactors, thus ensuring the conservation and sustainable utilization of H. annulare. The study warrants further scale-up production and pharmacological investigation that can be extended for pharmaceutical needs.