Optimization of phenolic yield of Carthamus oxyacantha Bieb. leaves and flowers extracts pertaining to the antioxidant and antidiabetic effect by response surface methodology.

Abstract

The study was designed to establish the pharmacognostic and pharmacological validation of Carthamus oxyacantha (C. oxyacantha) leaves and flowers crude extracts, the optimization of crude extracts as per Box-Behnken's experimental design, indicated that ethanolic leaves and flowers extracts of C. oxyacantha prepared at extraction conditions of run # 3 and 8 (ELE-3 and EFE-8) respectively, presented the highest level of dependent variables, while, the alpha-amylase IC₅₀ value (5.976 µg/mL) of ELE-3 was relatively closer to that of standard acarbose (3.524 µg/mL). Chromatographic fingerprinting of ELE-3 resulted in the identification of bioactive phenolic compounds (quantitatively; 11.47 µg/mL of gallic acid and 8.27 µg/mL of quercetin). Furthermore, acute oral toxicity of ELE-3 suggested the LD₅₀ > 2000 mg/kg. The findings of an in vivo antidiabetic study indicated that ELE-3 (100 and 500 mg/kg) produced a significant reduction in alloxan induced hyperglycemia of diabetic rats. Thus, the present study demonstrated the pharmacognostic and pharmacological implications of C. oxyacantha leaves and flowers crude extracts and revealed the remedial role of optimized extract (ELE-3) for the management of diabetes mellitus owing to its oxidative stress-lowering tendency and presence of bioactive phenolic compounds.