A new monoterpene glucoside and complete assignments of dihydroflavonols of Pulicaria jaubertii: potential cytotoxic and blood pressure lowering activity

Abstract

One new monoterpene glucoside and five dihydroflavonols were isolated for the first time from the aerial parts of Pulicaria jaubertii and identified as p-menthane-2-O-β-D-glucopyranoside [1], dihydroquercetin (taxifolin) [2], 7,3′-di-O-methyltaxifolin [3], 3′-O-methyltaxifolin [4], 7-O-methyltaxifolin (padmatin) [5] and 7-O-methyl-dihydrokampferol (7-O-methylaromadenderin) [6]. The structures of these compounds were unambiguously assigned on the basis of NMR spectroscopic data (¹H, ¹³C, DEPT, HSQC, HMBC) and MS analysis. 2D-NMR methods required revision of assignments of H-6 and H-8 for dihydroflavonol compounds. Possible cytotoxic activity as well as blood pressure (BP) lowering activity were tested. The alcoholic extract showed cytotoxic activity against prostate carcinoma (PC-3), breast carcinoma (MCF-7) and hepatocellular carcinoma (HepG-2) human cell lines with IC₅₀ 19.1, 20.0 and 24.1 μg, respectively. The higher dose levels of the alcoholic extract significantly reduced normal BP of rats in a dose-dependent manner.

Keywords:

• Pulicaria jaubertii
• phytoconstituents
• cytotoxic activity
• blood pressure lowering effect

Acknowledgment

The authors would like to thank the Deanship of Scientific Research and the Institute of Scientific Research and Revival of Islamic Heritage at Umm Al-Qura University (Project ID: 4331009) for the financial support of biological evaluation and NMR analysis.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental data and research materials

Supplemental data for this article can be accessed at http://dx.doi.10.1080/14786419.2015.1055492.

Additional information

Funding

This work was financially supported by the Institute of Scientific Research and Revival of Islamic Heritage at Umm Al-Qura University, Saudi Arabia [grant number 4331009].