Studies on phytochemical, antioxidant, anti-inflammatory and analgesic activities of Euphorbia dracunculoides

Background: Plants provide an alternative source to manage various human disorders due to diverse metabolites. Euphorbia dracunculoides of family Euphorbiaceae is used by local practitioners in rheumatism, epilepsy, edema, snake bite, warts and also possesses diuretic and purgative effects. The present study evaluated the antioxidant, anti-inflammatory and analgesic activities of various extracts of E. dracunculoides. Further, phytochemical constituents of the leading extracts were also investigated. Methods: Dry powder of E. dracunculoides was extracted with n-hexane (EDH), acetone (EDA), ethanol (EDE), ethanol + water (1: 1) (EDEW) and methanol (EDM) and screened for phytochemical classes, total phenolic (TPC) and flavonoid content (TFC). Antioxidant effects of the extracts were manifested by in vitro multidimensional assays. The anti-inflammatory and analgesic activities of the extracts were evaluated through carrageenan induced paw edema and hot plate test in rat. In addition, GC-MS analysis of EDH and HPLC-DAD analysis of EDEW was carried out to determine the presence of active constituents. Results: Qualitative analysis of various extracts of E. dracunculoides assured the existence of tannins and coumarins while presence of anthraquinones and anthocyanins was not traced in these extracts. Maximum quantity of TPC and TFC was recorded in EDEW followed by EDE. EDEW and EDE showed significant antioxidant activities with therapeutic potential against hydroxyl and phosphomolybdate radicals, beta-carotene bleaching assay and in reducing of iron while moderate to low scavenging abilities were recorded for DPPH, nitric oxide and for iron chelation. During anti-inflammatory activity after 4 h of drug administration the 300 mg/kg body weight dose of EDH (68.660 +/- 10.502 %) and EDE (51.384 +/- 8.623 %) exhibited strong anti-inflammatory activity and reduced the carrageenan-induced paw edema in rat as compared to standard drug diclofenac sodium (78.823 +/- 6.395 %). Treatment of rats with EDH (70.206 +/- 5.445 %) and EDE (56.508 +/- 6.363 %) after 90 min showed significant increase in percent latency time in hot plate test as compared to morphine (63.632 +/- 5.449 %) treatment in rat. GC-MS analysis of EDH indicated the presence of 30 compounds predominantly of steroids and terpenoids. HPLC-DAD analysis against known standards established the presence of rutin, catechin, caffeic acid and myricetin in EDEW. Conclusion: Our results suggest that presence of various polyphenolics, terpenoids and steroids render E. dracunculoides with therapeutic potential for oxidative stress and inflammation related disorders.