| Title: | Occurrence of glycosidically conjugated 1-phenylethanol and its hydrolase beta-primeverosidase in tea (Camellia sinensis) flowers |
| Author(s): | Zhou Y; Dong F; Kunimasa A; Zhang Y; Cheng S; Lu J; Zhang L; Murata A; Mayer F; Fleischmann P; Watanabe N; Yang Z; |
| Address: | "Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences , Xingke Road 723, Tianhe District, Guangzhou 510650, China" |
| ISSN/ISBN: | 1520-5118 (Electronic) 0021-8561 (Linking) |
| Abstract: | "A previous study found that 1-phenylethanol (1PE) was a major endogenous volatile compound in tea (Camellia sinensis) flowers and can be transformed to glycosically conjugated 1PE (1PE-Gly). However, occurrences of 1PE-Gly in plants remain unknown. In this study, four 1PE-Glys have been isolated from tea flowers. Three of them were determined as (R)-1PE beta-d-glucopyranoside ((R)-1PE-Glu), (S)-1PE-Glu, and (S)-1PE beta-primeveroside ((S)-1PE-Pri), respectively, on the basis of NMR, MS, LC-MS, and GC-MS evidence. The other one was identified as (R)-1PE-Pri on the basis of LC-MS and GC-MS data. Moreover, these 1PE-Glys were chemically synthesized as the authentic standards to further confirm their occurrences in tea flowers. 1PE-Glu had a higher molar concentration than 1PE-Pri in each floral stage and organ. The ratio of (R) to (S) differed between 1PE-Glu and 1PE-Pri. In addition, a 1PE-Gly hydrolase beta-primeverosidase recombinant protein produced in Escherichia coli exhibited high hydrolysis activity toward (R)-1PE-Pri. However, beta-primeverosidase transcript level was not highly expressed in the anther part, which accumulated the highest contents of 1PE-Gly and 1PE. This suggests that 1PE-Gly may not be easily hydrolyzed to liberate 1PE in tea flowers. This study provides evidence of occurrences of 1PE-Glys in plants for the first time" |
| Keywords: | "Benzyl Alcohols/analysis/chemistry/isolation & purification/metabolism Camellia sinensis/*chemistry/enzymology/growth & development China Chromatography, High Pressure Liquid Crops, Agricultural/*chemistry/enzymology/growth & development Flowers/*chemistr;" |
| Notes: | "MedlineZhou, Ying Dong, Fang Kunimasa, Aiko Zhang, Yuqian Cheng, Sihua Lu, Jiamin Zhang, Ling Murata, Ariaki Mayer, Frank Fleischmann, Peter Watanabe, Naoharu Yang, Ziyin eng Comparative Study Research Support, Non-U.S. Gov't 2014/07/30 J Agric Food Chem. 2014 Aug 13; 62(32):8042-50. doi: 10.1021/jf5022658. Epub 2014 Aug 1" |
