Investigation of Antioxidant Potential of the Ethanolic Extract from <i>Nelumbo Nucifera</i> by Immersion and Ultrasound-assisted Extraction Techniques

Abstract

Bioactive compounds such as antioxidants play a fundamental role in human health and nutrition. Furthermore, aquatic plants are considered a valuable and appropriate resource of antioxidants. Nelumbo nucifera is one of the native aquatic plants of the Anzali International Wetland. The current research aimed to produce ethanolic extracts of several segments (leaf, flower, fruit, and stem) of N. nucifera using IE and UAE (in three durations of 20, 40, and 60 min) procedures. Then, the TPC, TFC, DPPH, and FRAP assays to examine antioxidant attributes in diverse treatments were appraised. The results highlighted that the highest amount of TPC was related to the leaf ethanolic extract at 40 min at the rate of 102.38±16.87 µg GAE/g DW by the UAE method. In contrast, the ethanolic extract of the leaf at 60 min at the rate of 185.16±43.79 µg QE/g DW by the UAE method illustrated the maximum level of TFC. In part of DPPH; the highest amount of antioxidant properties was obtained in the flower ethanolic extract at the rate of 0.70±0.01% by IE method and also the topmost value of FRAP was related to the ethanolic extract of leaf at 60 min at the rate of 321.56±16.08 mg GAE/g DW by UAE method. Overall, the UAE method appeared more efficient analogized to the IE method. These findings suggest that the ethanolic extract of N. nucifera can be regarded as a confident source of bioactive compounds such as natural antioxidants for nutritional, pharmaceutical, nutraceutical, and medical intentions.