Optimization of water extract of Cinnamomum burmannii bark to ascertain its in vitro antidiabetic and antioxidant activities

Abstract

Abstract The antidiabetic and antioxidant activity of water extract of Cinnamomum burmannii bark is well documented. This research aimed to optimize cinnamon water extraction process and verify active components instigating its in vitro antidiabetic activity. The study employed a Design Expert 7.0 program to derive factorial design and optimization conditions. The extraction step comprised of three factors (temperature, concentration and time of extraction) and two levels (low and high), with four responses observed (yield, total phenolic content, IC50DPPH antioxidant activity, and IC50 α-glucosidase inhibition). The polynomial equations revealed influence and interaction among the selected factors to the responses and obtained overlay optimization of factors to responses. The results indicated that optimal temperature, concentration, and extraction time were 98 °C, 30% and 20 min, respectively. Corresponding DPPH, α-glucosidase, TPC, and yield values were 3.45 μg/mL, 0.50 μg/mL, 259.08 μg GAE/mg of sample, 6.28%, respectively. LCMS analysis of the optimum extract confirmed typical characteristic of C. burmannii contents (coumarins, polymers of proanthocyanidins A-type and protonated heterodimer of flavan-3-ol group). The optimized water extract of C.burmannii has the potency to assist in complementary therapy to modulate diabetes mellitus.