Tyrosinase Inhibition activity of combined camellia sinensis (L.) O. kuntze extract and oryza sativa (L.) extract.

Abstract

A multi-copper enzyme called tyrosinase is essential to produce melanin. However, the overproduction of melanin can be unsightly, so tyrosinase inhibitors are extensively studied today, especially as inhibitors in nature. In this study, the efficacy of a combination of Camellia Sinensis (green tea) and Oryza Sativa (rice bran) to inhibit the activity of tyrosinase was evaluated. While Oryza Sativa was extracted with EtOH using the ultrasonic method, Camella Sinensis was extracted using the Soxhlet method. The weight of sample obtained after C.sinensis and O.sativa extraction was 2.52g ± 0.2 and 5.08g ± 0.22, respectively. After extraction, samples were obtained to use TLC, LC-MS, and GC-MS techniques to identify and quantify the components. Consequently, whereas the rice bran sample included anthocyanins and fatty acids, the green tea sample contained several polyphenol components including GC, EGC, EC, EGCG, and ECG. Both the extracted samples and their combination showed tyrosinase activity inhibition. Due to the green tea extract's antioxidant protection, the combination of the two extracts at 100 ppm achieved the maximum percentage inhibition at the ratio C.sinensis:O.sativa (5:5) of 56.76% ± 0.15. The IC50 value of the ratio 5:5 was 66.30ppm, which was quite close to that of Kojic acid (51.35ppm). So, it had potential to replace kojic acid as an inhibitor of tyrosinase in cosmetics. The results of an evaluation of the tyrosinase inhibitory activity of two serum products (one water-based and the other oil-based) with the ratio C.sinensis:O.sativa (5:5) were 18.7% ± 0.38 and 22.5% ± 0.41, respectively