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This study examined the volatile organic compounds (VOCs) and metabolites of glucosinolate (GLS) contained in kimchi and analyzed GLS using myrosinase. The analysis was conducted using gas chromatography-time of flight (GC-TOF), and VOC and the metabolite quantities were detected and analyzed. Based on 22 samples, tests were conducted, and 12 metabolites and 52 VOCs were found. When the detected metabolites were compared in general, the rate of isothiocyanate, which is well known for its anticancer effects and various other activities, was the highest. A total of 52 VOCs, including 15 aliphatic hydrocarbons, 7 acids, and 6 alcohols, were detected by GC-TOF. Therefore, the analytical methods provide a good basis to examine VOC and GLS metabolites; furthermore, the methods are of great help to secure excellent kimchi and evaluate its quality.

A new compound, 9-dihydroxyl-2'-O-(Z)-cinnamoyl-7-methoxy-aloesin (1), and eight known compounds (2–9) were isolated from Aloe vera. Their structures were elucidated using 1D/2D nuclear magnetic resonance and mass spectra. Compound 9 exhibited reversible competitive inhibitory activity against the enzyme tyrosinase, with an IC50 value of 9.8 ± 0.9 µM. A molecular simulation revealed that compound 9 interacts via hydrogen bonding with residues His244, Thr261, and Val283 of tyrosinase. Additionally, compounds 3 and 7 were shown by half-leaf assays to exhibit inhibitory activity towards Pepper mild mottle virus.

A sensitive and robust HPLC method with fluorescence detector (FLD), photochemical reaction device (PHRED) was developed to determine Aflatoxins (B1, B2, G1, and G2) and Ochratoxin A in animal feeds. Immunoaffinity columns (IAC) was used to purify the samples. According to monitoring resulted with the established method, aflatoxin and ochratoxin A were found in 44 of 496 domestic commercial samples (8.9% detection rate) and the concentration ranges were 1.76–162.69 μg/kg for Aflatoxin B1, 23.01–45.42 μg/kg for Ochratoxin A in 2015. In 2016, % detection rate was 22.2% (115 of 518 samples) and the concentration ranges are 1.76–43.69 μg/kg for Aflatoxin B1, 3.38–15.80 μg/kg for Ochratoxin A. The developed method was specific and reliable and is suited for the routine analysis of aflatoxin in animal feed.

A novel and simple method for detecting five glucosinolates (glucoalyssin, gluconapin, glucobrassicanapin, glucobrassicin, and 4-methoxyglucobrassicin) in kimchi was developed using liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS). The chromatographic peaks of the five glucosinolates were successfully identified by comparing their retention times, mass spectra. The mobile phase was composed of A (acetonitrile) and B (water). As for glucosinolate, the relative quantities were found through sinigrin, and five different compounds that have not been previously discovered in kimchi were observed. Monitoring was carried out on the glucosinolate in 20 kimchis distributed in markets, and this study examined the various quality and quantity compositions of the five components. The glucoalyssin content ranged from 0.00 to 7.07 μmol/g of day weight (DW), with an average content of 0.86 μmol/g of DW, whereas the gluconapin content ranged from 0.00 to 5.85 μmol/g of DW, with an average of 1.17 μmol/g of DW. The content of glucobrassicanapin varied between 0.00 and 11.87 μmol/g of DW (average = 3.03 μmol/g of DW), whereas that of glucobrassicin varied between 0.00 and 0.42 μmol/g of DW (average = 0.06 μmol/g of DW). The 4-methoxyglucobrassicin content ranged from 0.12 to 9.36 μmol/g of DW (average = 3.52 μmol/g of DW). A comparison of the contents revealed that, in most cases, the content of 4-methoxyglucobrassicin was the highest.

A rapid high performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD), using a carbohydrate column, was developed for simultaneous determination of N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc) in dairy foods. Sample preparation was performed by precipitation using acetonitrile. The limits of detection were 2.097 mg/L for GlcNAc and 3.247 mg/L for GalNAc. The limits of quantification were 6.043 mg/L for GlcNAc and 9.125 mg/L for GalNAc. Accuracy ranged from 96.4 to 105.7% for GlcNAc and from 97.1 to 104.1% for GalNAc. The precision of the method was