Assessing the potential of a sustainable bean leaf extract with abscisic acid in pear ripening restoration

Introduction: Rocha pear (Pyrus communis L. cv Rocha) is a Portuguese cultivar stored with 1-MCP in controlled atmosphere to extend storage life and prevent postharvest issues. However, 1-MCP obstructs the normal ripening, impacting pear quality for consumers. Several strategies have been applied to reboot the ripening of pear under 1-MCP effect, such as the application of higher temperatures, exogenous ethylene or a combination of both. However, these treatments demand high energy consumption. Some phytohormones, like abscisic acid (ABA), have been shown to accelerate ripening by stimulating ethylene production, firmness loss, coloring, among other ripening markers. Objective: In this study, leaves from bean plants derived from agri-food wastes were explored to extract phytohormones with focus on ABA, using a sustainable approach. Further the study aimed to investigate the potential of this green extract as a ripening inducer for pears under the 1-MCP effect. Time course physiological and biochemical analysis comparison with ‘Rocha’ pear treated with synthetic ABA was performed. Conclusions: The extraction approach developed in this study extracted ABA from bean leaves using only water under cold conditions. This suggests a sustainable approach by repurposing agricultural by-products; Bean leaves extract and synthetic ABA treatment of pears, under the influence of 1-MCP, resulted in increased respiration and ethylene production after 15 days. This was accompanied by higher SSC, color and firmness loss suggesting that ABA may be inducing the ripening process; Evaluating natural and synthetic ABA on pear ripening is essential to determine the effectiveness of the natural source relative to the conventional synthetic version. Despite lower ABA concentration in the natural extract, similar responses to synthetic ABA suggest the involvement of not only ABA but other bioactive compounds; The results of this study could have implications for the development of eco-friendly and sustainable practices in agri-food waste utilization and fruit post-harvest management.