Camellia japonica is a plant species belonging to the Theaceae family; it is widespread in Asia. Although Camellia sinensis (tea) is one of the best-known species, C. japonica is scarcely known beyond its current ornamental value. However, C. japonica is recorded to have been used in traditional medicine, indicating its potential health benefits. The increasing population and demand for natural products has necessitated the investigation of potential bioactive constituents of such plants, which in many cases, has been correlated with their antioxidant properties. In this work, screening was performed on the potential of extracts obtained from C. japonica leaves as a source of natural antioxidant compounds. Antioxidant activity was determined in vitro by testing their radical scavenging activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS [2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)]. Total phenolic content (TPC) was measured as gallic acid equivalents (mg GAE/g) in accordance with previously established protocols. The results showed an IC50 value of 23.74 µg/mL for both DPPH and ABTS tests. TPC was measured as 36.67 mg GAE/g dry weight. These findings indicate that C. japonica leaves may have significant antioxidant activity, which can be related to their TPC. Further investigation of the phytochemical content and bioactivities of this matrix is required for its evaluation in health-related applications such as functional foods, nutraceuticals and cosmetics.
References
Christodouleas, D. C., Fotakis, C., Nikokavoura, A., Papadopoulos, K., & Calokerinos, A. C. (2015). Modified DPPH and ABTS Assays to Assess the Antioxidant Profile of Untreated Oils. Food Analytical Methods, 8(5), 1294–1302. https://doi.org/10.1007/s12161-014-0005-6
Genwali, G. R., Acharya, P. P., & Rajbhandari, M. (2013). Isolation of Gallic Acid and Estimation of Total Phenolic Content in Some Medicinal Plants and Their Antioxidant Activity. Nepal Journal of Science and Technology, 14(1), 95–102. https://doi.org/10.3126/njst.v14i1.8928
