Diketopiperazine indole alkaloids from hemp seed

Publication date: December 2016 Source:Phytochemistry Letters, Volume 18 Author(s): Xiaoli Yan, Yuefang Zhou, Jiajing Tang, Mei Ji, Hongxiang Lou, Peihong Fan Hemp seeds from non-drug varieties of Cannabis sativa L. are an important source of food and medicine. In continuation of our ongoing study on hemp seed, two pairs of stereoisomers of diketopiperazine indole alkaloid (12S, 22R)-Dihydroxyisoechinulin A (1), (12S, 22S)-Dihydroxyisoechinulin A (2) and (12R/S)-Neoechinulin A (3) were isolated. Their structures were elucidated with UV, IR, NMR, MS, CD spectra, ECD and chiral HPLC analysis techniques. This type of alkaloid is more often reported from fungi, such as Aspergillus and Eurotium, than from plant sources. Since common molds can contaminate herbal medicines, various hemp seed samples and the metabolites of the main fungi isolated from hemp seed were analyzed using HPLC. The data suggested that the isolated compounds are rare constituents of hemp seed, rather than fungal contamination. Thus, in this study, these compounds were isolated from hemp seed for the first time, and a previous study’s prediction of endogenous indole alkaloids in hemp was confirmed. Meanwhile, Neoechinulin A could promote SIRT1 expression in HEK293 cell lines. SIRT1 is becoming an important drug target for new therapies in the treatment of neurodegenerative diseases. Graphical abstract
Source: Phytochemistry Letters - Category: Chemistry Source Type: research