Phenolic Compounds in the Leaves of Two Alpine Pedicularis Species in Bhutan

Abstract

Phenolic compounds in the leaves of Pedicularis siphonantha and P. ludlowiana distributed in Bhutan, were surveyed. This is the first report on the phenolic composition of both plants. Five flavones, luteolin 7-O-rutinoside, luteolin 7-O-glucoside, luteolin 7-O-glucuronide, luteolin and apigenin 7-O-rutinoside, and a phenylpropanoid, acteoside (verbascoside) were identified. The flavonoid composition in the leaves of the two species showed differences in glycosylation patterns and other characteristics, and some components isolated from P. ludlowiana endemic to Bhutan were reported for the first time from plants of this genus. In this study, we succeeded in preparing samples in good condition and obtained interesting results for future analysis, including chemotaxonomic and chemical ecological findings.