ABSTRACT
The volatile components of both peel and juice of Japanese citrus, Kabosu (Citrus sphaerocarpa Hort. ex Tanaka) were investigated using SAFE (Solvent Assisted Flavor Evaporation) technique after solvent extraction. In this study, wine lactone, rose oxide, (2E)-4,5-epoxy-2-decenal, mintsulfide, and indole were newly identified from Kabosu. AEDA (Aroma Extract Dilution Analysis) of the oxygenated fraction of the peel extract showed high FD (Flavor Dilution) factors for linalool, (2E)-4,5-epoxy-2-decenal, octanal, (4Z)-decenal, beta-citronellol, geraniol, and wine lactone, while wine lactone, linalool, eugenol, geraniol, and (2E)-4,5-epoxy-2-decenal from the juice extract. The enantiomeric distribution of linalool, cis-rose oxide, beta-citronellol, and wine lactone were also determined using a multidimensional chiral GC/MS.
Subject(s)
Citrus/chemistry , Beverages/analysis , Fruit/chemistry , Gas Chromatography-Mass Spectrometry , Indicators and Reagents , Molecular Conformation , Odorants , Plant Extracts/chemistry , Solvents , StereoisomerismABSTRACT
The reactants produced by action of a purified unique dye-decolorizing peroxidase, DyP, on a commercial anthraquinone dye, Reactive Blue 5, were investigated using electrospray ionization mass spectrometry (ESI-MS), thin-layer chromatography (TLC), and (1)H- and (13)C- nuclear magnetic resonance (NMR). The results of ESI-MS analysis showed that phthalic acid, a Product 2 (molecular weight 472.5), and a Product 3 (molecular weight 301.5), were produced. Product 2 and Product 3 were generated by usual peroxidase reaction, whereas phthalic acid was generated by hydrolase- or oxygenase-catalyzed reaction. One potential associated product, o-aminobenzene sulfonic acid, was found to be converted to 2,2'-disulfonyl azobenzene by ESI-MS and NMR analyses. From these results, we propose, for the first time, the degradation pathway of an anthraquinone dye by the enzyme DyP.
