The antioxidant compounds isolated from the fruits of chinese wild raspberry Rubus Chingii Hu

Abstract

Raspberry, the fruit of Rubus Chingji Hu, is a widely distributed economic staple food in China. It has long been used as a traditional medicine in mainland China to treat kidney enuresis, nocturnal emission and premature ejaculation in clinic. In this paper, six known compounds (1 – 6) were purified from the fruits of Rubus chingji. Their structures were elucidated as (16α)-16,17-dihydroxy-ent-kauran-2-one17-O-β-D-glucopyranoside (1), (16R) -16,17-dihydroxy-ent-kaurane-2-one (2), 3,3′-di-O-methylellagic acid 4-(5′′-acetyl)-α-L-arabinofuranoside (3), quercilicoside A (4), esculetine (5) and ethyl-β-D-glucoside (6). All the compounds were isolated from Rubus Chingji Hu for the first time. Compounds 3 and 5 shown distinctive free radical scavenging activities in DPPH and FRAP assays. In addition, no cytotoxicity was observed for compounds 3 and 5 against different cancer cells, suggesting that they might be useful as potential antioxidant agents against various reactive oxygen species.

Keywords:

• Rosaceae
• Rubus chingji Hu
• terpenes
• ent-kaurane diterpene
• antioxidant activity
• cytotoxicity

Acknowledgements

The authors thank Dr. Qiang He of the Shaanxi Entry-exit Inspection and Quarantine Bureau for HRESIMS testing. This research was supported by the Scientific and Technological Projects of Shaanxi Province in China (2015SF087), the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shaanxi Province (302-253081601) and the Research Fund of Shaanxi Key Laboratory of Comprehensive Utilization of Tailings Resources (2014SKY-WK003).

Disclosure statement

The authors declare no conflicts of interest with respect to this work.