Carrageenan-mediated polyelectrolytic precipitation for bromelain extraction from Ananas Comosus: evaluating the effects of bromelain solution variables and carrageenan levels on yield and specific activity

Introduction: Pineapple (Ananas comosus Merr.) is a widely popular fruit, commonly used in various fruit-based products (Ataide et al., 2019; Campos et al., 2019). The byproducts from pineapple processing, which are rich in bioactive compounds like bromelain, offer an environmentally friendly approach to waste management. Bromelain, a protease primarily found in pineapple stems, is typically extracted using techniques such as solvent precipitation and ultrafiltration (Ketnawa & Rawdkuen, 2011; Pratiwi et al., 2020; Schieber et al., 2001; Simões et al., 2022). Recently, polyelectrolyte precipitation has gained attention as a green alternative for protein concentration and purification, ensuring the integrity of proteins while facilitating their separation (Chakraborty et al., 2021; Mala et al., 2021; Rajan & Dunna, 2022). Objective: This study aimed to employ the polyelectrolytic precipitation with carrageenan (Carr) to assess a process for efficient bromelain extraction from pineapple stem and peel fractions. Several sequential steps for bromelain purification were applied to obtain the best end-product for potential commercialization, like centrifugations, pellet washing and different stock Carr concentration. Conclusion: Polyelectrolytic precipitation with Carr concentrations of 5 mg/ml, or higher, significantly impacts precipitate yield (ca. >60%) and specific proteolytic activity for both fractions. The enzyme separation pH affects the activity, exhibiting higher values for alkaline pH. Extracting bromelain from pineapple waste offers a sustainable solution for waste reduction and promotes health-focused products, supporting a zero-waste approach in pineapple production.