A sustainable method for potato side stream valorisation to obtain steroidal glycoalkaloids within a bioeconomic approach

Abstract

This study explores potato side streams as a source of valuable natural products, specifically steroidal glycoalkaloids (SGAs). A bioeconomic approach was envisioned for valorisation. The E-factor (environmental factor) was used as a key measurement tool to optimise the extraction of SGAs and to compare the extraction and hydrolysis with the semi synthesis of solanidine starting from diosgenin in a lab scale up to 6 g. In particular, extraction was significantly optimised through the use of a swing mill and cyclopentyl methyl ether (CPME) and dimethyl carbonate (DMC) as ‘green’ solvents. It was shown that the potato variant Innovator displayed the highest SGA content (∼20 mg per g dry weight), and flowers showed higher levels compared to leaves and berries. The results indicate that extraction with hydrolysis is a more environmentally friendly method, particularly when using fresh plant material. The study concludes that potato side streams can be valorised without affecting food streams, providing opportunities for natural products with potential applications in agriculture and beyond.