Study on the Antioxidant Activities of Gel Containing <i>Tagetes erecta</i> (L.)

Abstract

Tagetes erecta Linn. (Asteraceae), commonly known as marigold, is a common garden plant in Thailand. It was reported that antioxidant, antimycotic, and analgesic activities were found in Tagetes erecta. In this study, the alcoholic crude extracts of flowers of Tagetes erecta were evaluated its free radical scavenging properties by using 2,2diphenyl-1-picrylhydrazyl (DPPH) free radical. Butylated hydroxytoluene (BHT) was used as standard antioxidant. Tagetes erecta extract possessed the potency of DPPH radical scavenging activity (EC50 6.56±1.46 μg/ml) more than BHT (EC50 11.06±1.75 μg/ml). Later, it was prepared in gel formulation at concentration of 0.1 % w/w Tagetes erecta extract which Carbopol Ultrez 21 or Sepigel 305 was used as a gelling agent. Propylene glycol, Uniphen P-23, triethanolamine, and distilled water were used as ingredients. The physicochemical property was evaluated in terms of physical appearances, pH, viscosity, and antioxidant activity. All formulations possessed good antioxidant activity. In addition, it has good physical appearances, and pH ranged of 4 to 6. However, the viscosity depended on a polymer type and concentration of polymer.