• Journal of Microbiology and Biotechnology
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• v.30 no.2
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• pp.296-305
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• 2020

Tricholoma matsutake is an ectomycorrhizal fungus, related with the host of Pinus densiflora. Most of studies on T. matsutake have focused on mycelial growth, genes and genomics, phylogenetics, symbiosis, and immune activity of this strain. T. matsutake is known for its unique fragrance in Eastern Asia. The most major component of its scent is (R)-(-)-1-octen-3-ol and is biosynthesized from the substrate linoleic acid by the sequential reaction of lipoxygenase and peroxide lyase. Here, we report for the first time the biosynthesis of (R)-(-)-1-octen-3-ol of T. matsutake using the yeast Saccharomyces cerevisiae as a host. In this study, cDNA genes correlated with these reactions were cloned from T. matsutake, and expression studies of theses genes were carried out in the yeast Saccharomyces cerevisiae. The product of these genes expression study was carried out with Western blotting. The biosynthesis of (R)-(-)-1-octen-3-ol of T. matsutake in recombinant Saccharomyces cerevisiae was subsequently identified with GC-MS chromatography analysis. The biosynthesis of (R)-(-)-1-octen-3-ol with S. cerevisiae represents a significant step forward.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.767-791
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• 2023

To evaluate the effect of different cooking methods on the physicochemical quality and volatile organic compounds (VOC) of dairy beef round, twelve beef round pieces were divided into four groups: raw, boiling, microwave, and sous-vide. The sous-vide group had a higher pH than the boiling or microwave groups. The boiling group exhibited the highest shear force and CIE L^*, followed by the microwave and sous-vide groups (p<0.05). The sous-vide group received higher taste and tenderness scores from panelists (p<0.05) and showed significantly higher levels of aspartic and glutamic acids than the other groups. The sous-vide and microwave groups had the highest oleic acid and polyunsaturated fatty acid levels, respectively. The sous-vide group had significantly higher hypoxanthine and inosine levels than the other groups. However, the microwave group had higher inosine monophosphate levels than the other groups. The sous-vide group had a higher alcohol content, including 1-octen-3-ol, than the other groups. Octanal and nonanal were the most abundant aldehydes in all groups. (R)-(-)-14-methyl-8-hexadecyn-1-ol, p-cresol, and 1-tridecyne were used to distinguish the VOC for each group in the multivariate analysis. Sous-vide could be effective in increasing meat tenderness as well as taste-related free amino acid (aspartic acid and glutamic acid) and fatty acid (oleic acid) levels. Furthermore, specific VOC, including 1-octen-3-ol, 2-ethylhexanal ethylene glycol acetal, and 2-octen-1-ol, (E)-, could be potential markers for distinguishing sous-vide from other cooking methods. Further studies are required to understand the mechanisms underlying the predominant association of these VOC with the sous-vide cooking method.

• Korean Journal of Pharmacognosy
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• v.38 no.4
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• pp.376-381
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• 2007

Seven compounds were isolated from the MeOH extract of the seeds of Plantago asiatica L. and their structures were identified as ${\beta}-sitosterol$ (1), (24R)-6${\beta}$-hydroxy-24-ethyl-cholest-4-en-3-one (2), acteoside (3), geniposidic acid (4), 1-octen-3-ol 3-O-${\beta}$-D-xylopyranosyl$(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (5), plantainoside D (6) and plantamajoside (7) on the spectroscopic analysis. Among them, $(24R)-6{\beta}$-hydroxy-24-ethyl-cholest-4-en-3-one (2) and 1-octen-3-ol 3-O-${\beta}$-D-xylopyranosyl ($1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (5) were first isolated from this plant. Among them, geniposidic acid (4) showed the most potent inhibitory effect on melanogenesis, with inhibition rate of 41%.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.587-591
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• 2009

Volatiles in Artemisia princeps Pampan. cv. sajabal (sajabalssuk) and A. princeps Pampan. (ssuk) treated with different processing were analyzed using headspace-solid phase microextraction (HS-SPME)/gas chromatography- a mass selective detector (GC-MS). Sajabalssuk and ssuk were treated with steam distillation (SD) and freeze-dried/steam distillation (FD/SD) while controls were raw sajabalssuk and raw ssuk. Sajabalssuk had significantly more total volatiles than ssuk in control and FD/SD treated samples (p<0.05). Major volatiles in raw sajabalssuk were 2-hexenal, 1,8-cineol, trans-caryophyllene, and hexanal while those in raw ssuk were 1-hexanol, ${\beta}$-myrcene, limonene, and 2-hexenal, which implies that substantial lipid oxidation occurred in raw samples. Sajabalssuk with SD and FD/SD treatment had higher peak areas of 1,8-cineole, 4-terpineol, 1-octen-3-ol, and ${\alpha}$-terpineol while ssuk with SD and FD/SD treatment possessed 1,8-cineol, camphor, borneol, artemisia ketone, ${\alpha}$-thujone, and 1-octen-3-ol, which showed that steam distillation produced more volatiles from terpenoids than raw samples. Based on the results of HS-SPME/GC-MS, relative amounts of volatiles from lipid oxidation including 2-hexenal, hexanal, and 1-hexanol were reduced in sajabalssuk and ssuk with freeze-drying and/or steam distillation treatment.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.171-178
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• 2014

The purpose of this study was to analyse the volatile components of Thymus magnus Nakai extracted by different extraction methods and reproduce scent close to original plant based on the results. For this purpose, the essential oil of T. magnus was extracted by supercritical fluid extraction (SFE), water and steam distillation (WSD) and simultaneous steam distillation and extraction (SDE) methods. The compositions of the essential oil were analyzed by gas chromatography-mass spectrometry (GC-MS). Consequently, linalool (0.1%) and trans-sabinene hydrate (0.9%) contents in the essential oil extracted by SFE method of $40^{\circ}C$ - 400 bar condition were relatively higher than compositions of the essential oil extracted by different conditions. The contents of borneol (3.82%), terpinen-4-ol (0.3%) and caryophyllene oxide (2.2%) were relatively higher at $50^{\circ}C$ - 400 bar and the contents of ${\beta}$-bisabolene (5.88%), 1-octen-3-ol (0.31%), caryophyllene (2.91%), p-cymene (2.04%) and ${\gamma}$-terpinene (0.52%) were extracted relatively higher at $50^{\circ}C$ - 300 bar. The compositions of the essential oil extracted by SFE method of $50^{\circ}C$ - 200 bar condition contained relatively higher contents of thymol (77.63%) and carvacrol (5.65%). The contents of ${\alpha}$-bisabolol (0.17%), caryophyllene (6.46%), cis-${\alpha}$-bisabolene (1.52%) and ${\beta}$-bisabolene (20.65%) in the essential oil extracted by WSD method were relatively higher than compositions of the essential oil extracted by SFE method, and by SDE method we couldn't obtained essential oil. The results of this study could be utilized to reproduce scent close to original scent of T. magnus.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.76-85
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• 2009

This study determined the effect of refrigerated and thermal storage on the volatile profile of commercial aseptic soymilk. Volatile components in commercial aseptic soymilk stored either under refrigerated ($4^{\circ}C$) or thermal ($55^{\circ}C$) conditions for 30 days were periodically analyzed by combined solvent-assisted flavor evaporation-gas chromatography-mass spectrometry (SAFE-GC-MS). The concentrations of most of the volatile components, including aldehydes, ketones, alcohols, acids, nitrogen- and sulfur-containing compounds, alkylfurans, furan derivatives and phenolic compounds, were affected to a greater extent by thermal storage compared with refrigerated storage. Profound increases in some volatile compounds with low odor detection thresholds, such as hexanal, octanal, (E)-2-octenal, (E,E)-2,4-decadienal, 1-octen-3-ol, 3-ethyl-2,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, 2-pentylfuran, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, dimethyl trisulfide, guaiacol, 4-vinylguaiacol and 4-vinylphenol, were observed in thermal stored soymilk. The volatile profile changes caused by thermal storage may influence the aroma quality of thermal-stored aseptic soymilk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.236-242
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• 2005

To develop a new detection method using irradiation-induced volatile marker compounds of red pepper powder (RP), the volatile compounds of irradiated RP (0, 1, 3, 5, and 10 kGy) were analyzed by purge and trap (P&T)/solid phase microextraction (SPME)/gas chromatography/mass spectrometry (GC/MS) methods. A total of 51 and 31 compounds were detected in IRP by SPME and P&T methods, respectively. Among these, 25 compounds, which were composed of 4 hydrocarbons, 7 aldehydes, 1 ketone, 3 alcohols, 4 aromatic compounds, 2 esters and 4 miscellaneous compounds, showed irradiation dependent manner with significant positive correlation (p<0.01 or p<0.05) between irradiation dose and relative concentration. However, all compounds except 1,3-bis(1,1-dimethylethyl)benzene were not suitable as marker compounds because of their low determination coefficients ($R^2$<0.80) between irradiation dose and their concentrations, and detectablilty in nonirradiated sample. Therefore, only one compound, 1,3-bis(1,1-dimethylethyl)benzene, was tentatively identified as a volatile marker compound to detect irradiated RP.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1171-1176
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• 1996

The changes in volatiles of the model system were analyzed by GC and GC-MS before and after retorting. The GC data were analyzed statistically by applying the analysis of variance, and 42 peaks were selected at 5% significance level. Multivariate statistical analysis was performed with these 42 peaks as independent variables. Through the stepwise discriminant analysis, 8 peaks, which corresponded to the compounds such as 2-heptanone, cis-3-hexenal, 2-pentyl-furan, 1-methyl-trans-1,2-cyclohexanediol, 2-hexanone, 3-octanone, trans, trans-nona-2,4-dienal and 1-octen-3-ol, were obtained in sequence to distinguish the samples with and without retorting. The principal component analysis of a set of 8 independent variables resulted in 3 principal components which accounted for 96.1% of the variance, while the first principal component (PC 1) explained 76.5% of the total variance. In addition, through the factor analysis of the principal components, the peaks 11, 20 and 21 could be grouped togather in accordance with the direction and the size while the peaks 9, 33 and 39 constituted the second group in the direction.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.325-333
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• 2007

One bacterium with high proteinase production and spore-forming ability was isolated from korean traditional soybean paste(doenjang). The isolated strain was identified as Bacillus subtilis, based on gram-staining, biochemical properties and l6S rRNA gene sequencing, and designated as B. subtilis DJI. Its growth rate was very fast, and it reached its stationary phase within 9 h, and then started to form spores. Bacterial-koji and doenjang were prepared using B. subtilis DJI. Chemical components of the doenjang were determined after 2 months of aging period: amino nitrogen 507 mg%, crude protein 14.3%, crude fat 4.8% and water 54.9%. The composition of total and free amino acids and their ratios of doenjang were changed during the aging period. Among total amino acids in DJI doenjang, glutamic acid, aspartic acid, leucine and arginine were the major amino acids. The fibrinolytic activities of DJI doenjang and traditional doenjangs were 909.7 units/ml and $363.3{\sim}618.6\;units/ml$, respectively. Flavor compounds of DJI doenjang and traditional doenjang were extracted by SDE(simultaneous steam distillation and extraction), and analyzed by GC/MS; DJI doenjang possessed the typically favorable flavor compounds in traditional korean doenjang, with reduced off-flavor compounds.

• Food Science and Preservation
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• v.23 no.1
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• pp.117-126
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• 2016

This study was performed to provide information for improving the quality characteristics of tangerine peel Soksungjang. Tangerine peel Soksungjangs were prepared with 10% tangerine peel powder by addition of different koji such as Rhizopus oligosporus (RS, RTS) and Aspergillus oryzae (AS, ATS). As a result, the moisture content was not changed and crude protein content decreased during fermentation in all samples. The pH of RS (Soksungjang manufactured with Rhizopus oligosporus koji) and RTS (Soksungjang manufactured with Rhizopus oligosporus koji and 10% tangerine peel powder) was not changed, whereas pH of AS (Soksungjang manufactured with Aspergillus oryzae) and ATS (Soksungjang manufactured with Aspergillus oryzae koji and 10% tangerine peel powder) decreased rapidly after 10 days of fermentation. The acidity values of all the samples increased during fermentation. The major free sugars were glucose, fructose, and maltose; while, the major organic acids were citric acid, succinic acid, acetic acid, and lactic acid in all the samples. The amino nitrogen content and protease activity were highest in the AS and ATS. Conversely, the reducing sugar content and ${\alpha}$-amylase activity were highest in the RS and RTS. The major free amino acids in all samples were glutamic acid, lysine, leucine, and arginine. Sixty kinds of volatile flavor compounds were identified from all samples; the majority of which were 21 alcohols, 14 hydrocarbons, 5 esters, and others identifies as acids, ketones, and aldehydes.