Chemical Processing and Various Applications of Starch Extracted from Avocado Seeds: A Step towards Sustainable Food Waste Management

Abstract

A sustainable food waste management methodology has been proposed for the discarded seeds of avocados (Persia Americana mill) where starch is extracted from the seeds through a microwave assisted heating process using only water, and this starch is modified through chemical treatment into acrylamide starch and carboxymethylated starch. Native as well as modified variants of starch are characterized using fourier transform infrared spectroscopy (FTIR), which confirms the extraction of native starch and its chemical modification. The extracted and modified variants are then analyzed for their antioxidant properties against oxidative stress by checking their scavenging activity against DPPH (2,2-diphenyl-1-picrylhydrazyl). Moreover, the three variants of starch are tested for hemolytic activity in order to determine whether they are harmful to human blood, finally these three variants are checked for their activity against Escherichia coli and Staphylococcus bacteria, the root cause in most cases of bacterial infection in humans. The starch variants are found to be excellent antioxidants and all three starch variants indicate a very low hemolytic activity and significant antibacterial activity in comparison to widely used antibiotic Ciproflaxin. All these results indicate that avocado seeds waste can be an excellent non-conventional source of starch that can be used for sustainable applications in food and pharmaceutical industries.