Determination of Total Phenolic Content and Antioxidant Activity of Six Ornamental Plants

Abstract

Total phenolic content and antioxidant activity from six Indonesian ornamental plants have been studied. Those plants are Yellow Allamanda (Allamanda cathartica L.), Bigleaf Hydrangea (Hydrangea macrophylla (Thunb.) Ser.), Crystal Anthurium (Anthurium crystallinum Linden & André), Kapok Bush (Aerva sanguinolenta (L.) Blume), Siamese Calypha (Acalypha siamensis Oliv. Ex Gage), and Wishbone Flower/Bluewings (Torenia fournieri Linden ex E. Fourn). Extraction was carried out by maceration using ethanol as the extracting solvent. Total phenolic content was determined by the Folin Ciocalteu method. Antioxidant activity was measured using the 2.2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, and cupric ion reducing antioxidant capacity (CUPRAC) method. Based on the results obtained, Bigleaf Hydrangea has the highest yield and total phenolic content about 15.45% and 13.86 mg gallic acid/g dry powder respectively. Siamese Acalypha leaves have the highest antioxidant activity for all methods used namely DPPH, reducing power, and CUPRAC with a value of 180.45; 202,17; and 589.90 µmol trolox/g dry powder, respectively. This indicates that antioxidant activity is not only derived from phenolic compounds because Siamese Acalypha leaves which have lower total phenolic levels than Bigleaf Hydrangea leaves provide higher antioxidant capacity.