Liquid–liquid extraction of pectinase produced by Aspergillus oryzae using aqueous two-phase micellar system

•We optimized the extraction of pectinase produced by Aspergillus oryzae.•We used the industrial residue passion fruit peel.•The micellar Triton X-114/buffer system was efficient in contaminants removal.•This system can be exploited as low cost pectinase purification method.

Separation and purification of proteins, organic compounds and other biomolecules are feasible by liquid–liquid extraction based on phase separation in aqueous micellar solution. This work aimed to optimize the extraction of the pectinase enzyme produced by Aspergillus oryzae in a passion fruit peel media, using a micellar Triton X-114/sodium phosphate buffer system. Best condition for this extraction was evaluated in a 23 experimental factorial design with a centered face and three repetitions at the central point. The variable analyzed was the pectinase activity, and in this design, it varied from 0.233 to 0.601 U mL−1. The highest activity was obtained in the top phase at conditions 25 °C, 8% Triton X-114 (wt/wt) and 20% concentrated crude extract (wt/wt). The results indicated that this aqueous two-phase micellar system (ATPMS) was able to remove visible pigments and possible pectinase inhibitors present in fermented broth, that partitioned in the bottom phase. Therefore, this system can be exploited as a first step in pectinase purification from a low cost production system with potential industrial application.