New isolation process for bioactive food fiber from wild strawberry leaf

Abstract

Much attention has been paid recently to developing greener and sustainable technologies in the herbal medicine industry, which produces large amounts of waste. This work proposes a clean approach to isolating bioactive food fiber as polyphenolic-polysaccharide conjugates (PPCs) by combining ultrafiltration (UF) with shortening the process time, lowering the energy input, improving the water management, and reducing the organic solvent consumption while maintaining an acceptable yield and biological activity with higher selectivity for PPCs. A simple procedure using UF has high potential for industrial approaches. Leaves of wild strawberry (Fragaria vesca L.), which are waste from plant cultivation, were used. The study schedule was planned using modern experimental design with response surface methodology. The chemical character of the optimal product, its bioactivity, and its mechanisms of action were found to be similar to those of the isolate obtained conventionally. The product was highly branched arabinogalacturonan complexed with a lignin-type polyphenolic matrix containing three fractions with molar masses (Mp) of approximately 180 × 103, 12 × 103, and 6 × 103 g × mol−1. The optimal product and its fractions had anticoagulant activity on human blood plasma by serving as a Factor Xa inhibitor when mediated by antithrombin or as a Factor IIa inhibitor through the creation of complex with heparin cofactor II. The optimal product was more selective in its action than the conventionally obtained product.