SUGAR AND PROTEIN CONTENT, HYDROGEN PEROXIDE RADICAL SCAVENGING AND TOTAL ANTIOXIDANT CAPACITY OF Polianthes tuberosa L FLOWERS GROWN IN ALGERIA

Tuberose flowers (Polianthes tuberosa L.) belong to the Amaryllidaceae family and they are widely enhanced through their absolute and essential oils, especially in the perfume industry. However, the sugar and proteins of tuberose are still unknown. For this reason, this work aimed to quantify them, particularly in flowers, besides to the evaluation of their hydrogen peroxide radical scavenging and total antioxidant capacity. The obtained results revealed 79.51±0.08 mg glucose equivalent/g extract of sugar and 0.097±0.001 mg bovine serum albumin equivalent/g extract of proteins. These metabolites were quantified using phenol-sulfuric acid and Coomassie Blue methods, respectively. Furthermore, the antioxidant activity of flower extract was investigated using total antioxidant capacity (TAC) and hydrogen peroxide radical scavenging. The TAC assay indicated the inhibitory concentration of 50% of free radicals (IC50) was 0,09±0,01 mg/mL of flower extract, however, the scavenging ability against H2O2 showed the IC50 of 7,09±0,15 mg/mL of tuberose flower extract. This work contributes to the knowledge of tuberose flowers content in proteins and sugar, in addition to the total antioxidant and the H2O2 scavenging capacities.