Comparison of Ultrasound and Maceration Techniques for the Extraction of Polyphenols from the Mango Peel.

An investigation was carried out to extract the polyphenols from mango peels by ultrasound-assisted extraction (UAE) and maceration techniques and to assess the antioxidant potential and quantification of phenolic compounds by high performance chromatography. Results showed that highest extraction yield obtained through solvent methanol at 80% concentration level while ultrasound-assisted extraction was more efficient technique and led to comparatively higher polyphenols content than maceration. Highest polyphenols were extracted with 80% ethanol (67.58 mg GAE/g of extract) by employing UAE whereas least polyphenols (18.66 mg GAE/g of extract) were obtained with 100% ethyl acetate through maceration technique. The high antioxidant activity of mango peel extracts was exhibited in three antioxidant assays with 80% ethanolic extracts had the highest antioxidant activity 31.51 + 0.79 mM/100 g for ferric reducing antioxidant power, highest scavenging activity 83.19 + 0.96% and 67.23 + 0.85% for 2,2-Diphenyl-1-picrylhydrazyl and superoxide anion radical assays, respectively. Strong correlations between total polyphenols and antioxidant activity were observed. Practical Applications Polyphenols are the natural antioxidants in plants having a significant role in human health by prevention of certain oxidative stress-related diseases. Mango peels are the major agro-industrial wastes in fruit juice processing which are not further utilized despite being an abundant source of phenolic compounds even more than the mango pulp. The study revealed that mango peels as a potential source of phenolic compounds which may be utilized as an ingredient for the preparation of functional foods. [ABSTRACT FROM AUTHOR]