The Phytochemical and Biological Investigation of Root Native to the Kingdom of Saudi Arabia.

Extensive phytochemical analysis of different root fractions of Courb. (Euphorbiaceae) has resulted in the isolation and identification of 22 secondary metabolites. 6-hydroxy-8-methoxycoumarin-7--β-d-glycopyranoside () and 2-hydroxymethyl -methyltryptamine () were isolated and identified as new compounds along with the known diterpenoid (, , , and ), triterpenoid ( and ), flavonoid (, , , , and ), coumarinolignan (⁻), coumarin (), pyrimidine (), indole (, ), and tyramine-derived molecules (⁻). The anti-inflammatory, analgesic, and antipyretic activities were evaluated for fifteen of the adequately available isolated compounds (⁻, ⁻, , , , , and ). Seven (, , , , , and of the tested compounds showed a significant analgesic effect ranging from 40% to 80% at 10 mg/kg in two in vivo models. Compound could also prove its analgesic property (67.21%) when it was evaluated on a third in vivo model at the same dose. The in vitro anti-inflammatory activity was also recorded where all compounds showed the ability to scavenge nitric oxide (NO) radical in a dose-dependent manner. However, eight compounds (, , , , , , , and ) out of the fifteen tested compounds exhibited considerable in vivo anti-inflammatory activity which reached 64.91% for compound at a dose of 10 mg/kg. Moreover, the tested compounds exhibited an antipyretic effect in a yeast-induced hyperthermia in mice. The activity was found to be highly pronounced with compounds , , , , , and which decreased the rectal temperature to about 37 °C after 2 h of the induced hyperthermia (~39 °C) at a dose of 10 mg/kg. This study could provide scientific evidence for the traditional use of as an anti-inflammatory, analgesic, and antipyretic.