Microwave assisted extraction and evaluation of in vitro antioxidant activity of Cinnamomum aromaticum

Cinnamomum aromaticum or Chinese cinnamon, belonging to the laurel family (Lauraceae) is an evergreen tree native to southern China, Bangladesh, India, and Vietnam. The dried bark of C. aromaticum is used as a spice. In this study, extraction and evaluation of in vitro antioxidant activity of C. aromaticum bark with ethanol using microwave - assisted extraction and soxhlet extraction were carried out. Antioxidant properties of two extracts were investigated employing various established systems in vitro including 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, ABTS assay, total antioxidant activity, hydroxyl radical assay and total reducing power. Total phenolic content of microwave - assisted extract (MCA) and conventional extract of C. aromaticum (CCA) reached 546.2±0.45 and 543.9±0.86 mg/g dry weight, respectively, expressed as gallic acid equivalents, which were quantified using Folin-Ciocalteau reagent. Subsequently, total flavonoids content of MCA and CCA extracts were found to be 126±0.18 and 121±0.34 mg/g dry weight, respectively, expressed as rutin equivalents (P < 0.05). MCA and CCA showed excellent antioxidant in all test systems compared to standard ascorbic acid and the antioxidant activities of MCA were all superior to those of CCA. The results obtained in this study clearly indicate that C. aromaticum has a significant potential to use as a natural anti-oxidant agent.