Abstract

Background: Medicinal plants are considered as a useful source of antioxidants against diseases due to reducing free radicals. Caralluma tuberculata is one of such sources utilized by Iranian population as a traditional herbal medicine. Objectives: The present study aimed at investigating antioxidant activity, total phenolic content (TPC), and total flavonoid content (TFC) of C. tuberculata root hydroalcoholic extract (CRE) and aerial parts hydroalcoholic extract (CAE). Methods: Antioxidant properties were assessed using DPPH (1,1-dipheny 1,2-picryl hydrazyl), superoxide anion (O-2(center dot-)), nitric oxide (NO), ferric reducing antioxidant power, and anti-lipid peroxidation methods. TPC (mg pyrogallol/g extract) and TFC (mg quercetin/g extract) were measured by colorimetric methods. Results: The findings showed that both CAE and CRE were rich in phenolic and flavonoid compounds. TPC (40.12 +/- 1.2) and TFC (20.22 +/- 0.62) were higher in CAE compared to CRE (TPC = 25.01 +/- 0.85, TFC =15.11 +/- 0.71). Likewise, both CAE and CRE showed significant scavenging effects on DPPH, O-2(center dot-), and NO radicals and the effects of CAE was more potent (P < 0.05) compared to that of CRE. Also, plant extracts significantly inhibited lipid peroxidation in a dose-dependent manner (P < 0.05). Furthermore, CAE exhibited a more potent ferric reducing activity compared to CRE (510.21 +/- 8.2 vs. 450.2 +/- 9.3 mu M Fe2+/g extract, respectively) (P < 0.05). Conclusions: Based on the study findings, both CAE and CRE could be considered as potential sources of antioxidants and CAE was more effective than CRE.