• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.411-419
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• 2019

A comprehensive comparison of fatty acid and metabolite profiles in 8 species of perilla seeds harvested from Korea and China was carried out to understand the correlation between cultivation conditions and the quality of perilla seeds. Metabolomic studies revealed that the perilla seeds were distinct from each other, based on the partial least squares -discriminant analysis (PLS-DA) score plots; 23 compounds including metabolites, fatty acids, and phytosterols that predominantly contributed to this interspecies difference were identified. Changes in the growth environment affected these compounds. In particular, phenolic compounds were affected by rainfall and temperature. Moreover, temperature and altitude showed negative and positive correlations, respectively, to oleic acid. Although more studies on the effect of various environmental factors on cultivation of perilla plants as well as their seeds are needed, the present results provide information that would be useful in identifying perilla seeds produced in specific regions and in the cultivation of good quality perilla.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.199-209
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• 2018

Volatile organic compounds (VOCs) are increasingly been recognized as the chemical mediators of mold interactions, shaping their community dynamics, growth, and metabolism. Herein, we selectively examined the time-correlated (0 D-11 D, where D = incubation days) effects of intraspecies VOC-mediated interactions (VMI) on Aspergillus oryzae KCCM 60345 (S1), following co-cultivation with partner strain A. oryzae KACC 44967 (S2), in a specially designed twin plate assembly. The comparative evaluation of $S1_{VMI}$ (S1 subjected to VMI with S2) and its control ($S1_{Con}$) showed a notable disparity in their radial growth ($S1_{VMI}$ < $S1_{Con}$) at 5 D, protease activity ($S1_{VMI}$ > $S1_{Con}$) at 3-5 D, amylase activity ($S1_{VMI}$ < $S1_{Con}$) at 3-5 D, and antioxidant levels ($S1_{VMI}$ > $S1_{Con}$) at 3 D. Furthermore, we observed a distinct clustering pattern for gas chromatography-time of flight-mass spectrometry datasets from 5 D extracts of $S1_{VMI}$ and $S1_{Con}$ in principle component analysis (PC1: 30.85%; PC2: 10.31%) and partial least squares discriminant analysis (PLS-DA) (PLS1: 30.77; PLS2: 10.15%). Overall, 43 significantly discriminant metabolites were determined for engendering the metabolic variance based on the PLS-DA model (VIP > 0.7, p < 0.05). In general, a marked disparity in the relative abundance of amino acids ($S1_{VMI}$ > $S1_{Con}$) at 5 D, organic acids ($S1_{VMI}$ > $S1_{Con}$) at 5 D, and kojic acid ($S1_{VMI}$ < $S1_{Con}$) at 5-7 D were observed. Examining the headspace VOCs shared between S1 and S2 in the twin plate for 5 D incubated samples, we observed the relatively higher abundance of C-8 VOCs (1-octen-3-ol, (5Z)-octa-1,5-dien-3-ol, 3-octanone, 1-octen-3-ol acetate) having known semiochemical functions. The present study potentially illuminates the effects of VMI on commercially important A. oryzae's growth and biochemical phenotypes with subtle details of altered metabolomes.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.214-221
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• 2020

BACKGROUND: The demand for pesticide registration has kept increasing for minor crop cultivation in greenhouse since Positive List System (PLS) has been launched. Thus, much study on the evaluation of pesticide residues in minor crops is required to examine the demand. In this study, we evaluated residues of acetamiprid, boscalid, imidacloprid and pyraclostrobin in the minor crop mustard green to provide the potential data for their registration. METHODS AND RESULTS: Pesticide granule formulations of acetamiprid, boscalid, imidacloprid and pyraclostrobin were incorporated into soil and applied onto field soil surface at rates of 3 kg/10a, 6 kg/10a, 3 kg/10a and 6 kg/10a, respectively. The pesticides were also applied at the two times higher than the rates to compare the residues between the application rates. Mustard green seeds were sown 1 day after pesticide application and cultivated under greenhouse conditions. LC/MS/MS analyses coupled with a modified QuEChERs method were employed for determination of the pesticides in plant samples. The method limits of quantitation (LOQ) of the pesticides were 0.01 mg/kg, and the matrix calibration curves of the pesticides showed linearity with coefficient values of determination (r²) greater than 0.995. The average recovery values of the pesticides fortified in control samples at rates of LOQ and 10LOQ ranged from approximately 77.5% to 101.2% with relative standard deviation values lower than 14%. The pesticides in the mustard green samples cultivated for 53 days after sown were determined to be lower than the LOQ level. CONCLUSION: Acetamiprid, boscalid, imidacloprid and pyraclostrobin were found at a level lower than 0.01 mg/kg in the minor crop mustard green. Thus, their residues in mustard green would not violate PLS under greenhouse conditions.

• YAKHAK HOEJI
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• v.60 no.1
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• pp.29-35
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• 2016

Traditional Korean medicines may be managed more scientifically, through the development of logical criterion to verify their cultivation region. It contributes to advance the industry of traditional herbal medicines. Volatile compounds were obtained from 14 samples of domestic Taeksa and 30 samples of Chinese Taeksa by steam distillation. The metabolites were identified by NIST mass spectral library in the obtained gas chromatography/mass spectrometer (GC/MS) data of 35 training samples. The multivariate statistical analysis, such as Principal Component Analysis (PCA), Partial Least Squares Discriminant Analysis (PLS-DA), and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), were performed based on the qualitative and quantitative data. Finally trans-(2,3-diphenylcyclopropyl)methyl phenyl sulfoxide (47.265 min), 1,2,3,4-tetrahydro-1-phenyl-naphthalene (47.781 min), spiro[4-oxatricyclo[5.3.0.0.(2,6)]decan-3-one-5,2'-cyclohexane] (54.62 min), 6-[7-nitrobenzofurazan-4-yl]amino-morphinan-4,5-epoxy (54.86 min), p-hydroxynorephedrine (55.14 min) were determined as marker metabolites to verify candidates for the origin of Taeksa. The statistical model was well established to determine the origin of Taeksa. The cultivation areas of test samples, each 3 domestic and 6 Chinese Taeksa were predicted by the established OPLS-DA model and it was confirmed that all 9 samples were precisely classified.

• Journal of Biosystems Engineering
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• v.41 no.1
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• pp.51-59
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• 2016

Purpose: This study examined the performance of two spectroscopy methods and multivariate classification methods to discriminate viable pepper seeds from their non-viable counterparts. Methods: A classification model for viable seeds was developed using partial least square discrimination analysis (PLS-DA) with Fourier transform near-infrared (FT-NIR) and Raman spectroscopic data in the range of $9080-4150cm^{-1}$ (1400-2400 nm) and $1800-970cm^{-1}$, respectively. The datasets were divided into 70% to calibration and 30% to validation. To reduce noise from the spectra and compare the classification results, preprocessing methods, such as mean, maximum, and range normalization, multivariate scattering correction, standard normal variate, and $1^{st}$ and $2^{nd}$ derivatives with the Savitzky-Golay algorithm were used. Results: The classification accuracies for calibration using FT-NIR and Raman spectroscopy were both 99% with first derivative, whereas the validation accuracies were 90.5% with both multivariate scattering correction and standard normal variate, and 96.4% with the raw data (non-preprocessed data). Conclusions: These results indicate that FT-NIR and Raman spectroscopy are valuable tools for a feasible classification and evaluation of viable pepper seeds by providing useful information based on PLS-DA and the threshold value.

• Environmental Analysis Health and Toxicology
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• v.25 no.4
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• pp.295-306
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• 2010

Objectives : This study was undertaken to examine the metabolomic changes due to gender and diurnal variation at sampling time and to identify an appropriate time point for urine sampling in epidemiologic studies using metabolomic profiles. Methods : Urine samples were collected twice a day (morning and afternoon) from 20 healthy Korean adults after fasting for 8 hours. The metabolomic assay was investigated using $^1H$ NMR spectroscopy coupled with the principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The metabolites responsible for differentiation between groups were identified through the loading plot of PLS-DA and quantified using Chenomx NMR Suite with a 600 MHz library. Results : Metabolites responsible for differentiation in gender and sampling time were creatinine, trimethyl anine oxide (TMAO), hippurate, mannitol, citrate and acetoacetate. Dimethylamine showed difference only as a factor of diurnal time. The level of creatinine was higher in men compared to women, and the levels of citrate, TMAO, hippurate, mannitol, and acetoacetate were higher in women compared to men. The levels of creatinine, TMAO, hippurate, dimethylamine and mannitol were higher in the morning rather than the afternoon while those of citrate and acetoacetate were higher in the afternoon rather than the morning. Conclusions : Since urinary metabolomic profiles varied by gender and diurnal cycle, urine sampling should be performed at the same time point for all participants in epidemiologic studies using metabolomic profiles.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.301-313
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• 2017

Purpose: This study was conducted to discriminate between normal hulled barley and Fusarium (Fusarium asiaticum and Fusarium graminearum) infected hulled barley by using the near-infrared spectroscopy (NIRS) technique. Methods: Fusarium asiaticum and Fusarium graminearum were artificially inoculated in hulled barley and the reflectance spectrum of the barley spike was obtained by using a near-infrared spectral sensor with wavelength band in the range 1,175-2,170 nm. After obtaining the spectrum of the specimen, the hulled barley was cultivated in a greenhouse and visually inspected for infections. Results: From a partial least squares discriminant analysis (PLS-DA) prediction model developed from the raw spectrum data of the hulled barley, the discrimination accuracy for the normal and infected hulled barley was 99.82% (563/564) and 100% (672/672), respectively. Conclusions: NIRS is effective as a quick and nondestructive method to detect whether hulled barley has been infected with Fusarium. Further, it expected that NIRS will be able to detect Fusarium infections in other grains as well.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.411-419
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• 2012

Purpose: Nondestructive evaluation of seed viability is a highly demanded technique in the seed industry. In this study, hyperspectral imaging system was used for discrimination of viable and non-viable radish seeds. Method: The spectral data with the range from 400 to 1000 nm measured by hyperspectral reflectance imaging system were used. A calibration and a test models were developed by partial least square discrimination analysis (PLS-DA) for classification of viable and non-viable radish seeds. Either each data set of visible (400~750 nm) and NIR (750~1000 nm) spectra and the spectra of the combined spectral ranges were used for developing models. Results: The discrimination accuracy of calibration was 84% for visible range and 76.3% for NIR range. The discrimination accuracy of test was 84.2% for visible range and 75.8% for NIR range. The discrimination accuracies of calibration and test with full range were 92.2% and 92.5%, respectively. The resultant images based on the optimal PLS-DA model showed high performance for the discrimination of the nonviable seeds from the viable seeds with the accuracy of 95%. Conclusions: The results showed that hyperspectral reflectance imaging has good potential for discriminating nonviable radish seeds from massive amounts of viable seeds.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.924-937
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• 2020

The purpose of this study was to investigate the meat metabolite profiles related to differences in beef quality attributes (i.e., high-marbled and low-marbled groups) using nuclear magnetic resonance (NMR) spectroscopy. The beef of different marbling scores showed significant differences in water content and fat content. High-marbled meat had mainly higher taste compounds than low-marbled meat. Metabolite analysis showed differences between two marbling groups based on partial least square discriminant analysis (PLS-DA). Metabolites identified by PLS-DA, such as N,N-dimethylglycine, creatine, lactate, carnosine, carnitine, sn-glycero-3-phosphocholine, betaine, glycine, glucose, alanine, tryptophan, methionine, taurine, tyrosine, could be directly linked to marbling groups. Metabolites from variable importance in projection plots were identified and estimated high sensitivity as candidate markers for beef quality attributes. These potential markers were involved in beef taste-related pathways including carbohydrate and amino acid metabolism. Among these metabolites, carnosine, creatine, glucose, and lactate had significantly higher in high-marbled meat compared to low-marbled meat (p<0.05). Therefore, these results will provide an important understanding of the roles of taste-related metabolites in beef quality attributes. Our findings suggest that metabolomics analysis of taste compounds and meat quality may be a powerful method for the discovery of novel biomarkers underlying the quality of beef products.

• Journal of Ginseng Research
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• v.37 no.2
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• pp.248-253
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• 2013

Leaves from Panax ginseng Meyer (Korean origin and Chinese origin of Korean ginseng) and P. quinquefolius (American ginseng) were harvested in Haenam province, Korea, and were analyzed to investigate patterns in major metabolites using HPLC-based metabolic profiling. Partial least squares discriminant analysis (PLS-DA) was used to analyze the the HPLC chromatogram data. There was a clear separation between Panax species and/or origins from different countries in the PLS-DA score plots. The ginsenoside compounds of Rg1, Re, Rg2, Rb2, Rb3, and Rd in Korean leaves were higher than in Chinese and American ginseng leaves, and the Rb1 level in P. quinquefolius leaves was higher than in P. ginseng (Korean origin or Chinese origin). HPLC chromatogram data coupled with multivariate statistical analysis can be used to profile the metabolite content and undertake quality control of Panax products.