Liquid–liquid extraction of commercial and biosynthesized nisin by aqueous two-phase micellar systems

• Published in: Enzyme and microbial technology Vol. 42; no. 2; pp. 107 - 112
• Main Authors: Jozala, A.F., Lopes, A.M., Mazzola, P.G., Magalhães, P.O., Vessoni Penna, T.C., Pessoa, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 2008; Elsevier Science
• Subjects: Aqueous two-phase micellar system; Biological and medical sciences; Biotechnology; Cloud-point extraction; Concentration; Fundamental and applied biological sciences. Psychology; Lactobacillus; Nisin; Protein purification; Triton X-114; Nisin; Aqueous two-phase micellar system; Cloud-point extraction; Concentration; Triton X-114; Protein purification; Biphasic system; Purification; Bacteriocin; Extraction; Protein
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/j.enzmictec.2007.08.005

Nisin is a natural additive for conservation of food, and can also be used as a therapeutic agent. Nisin inhibits the outgrowth of spores, the growth of a variety of Gram-positive and Gram-negative bacteria. In this paper we present a potentially scalable and cost-effective way to purify commercial and biosynthesized in bioreactor nisin, including simultaneously removal of impurities and contaminants, increasing nisin activity. Aqueous two-phase micellar systems (ATPMS) are considered promising for bioseparation and purification purposes. Triton X-114 was chosen as the as phase-forming surfactant because it is relatively mild to proteins and it also forms two coexisting phases within a convenient temperature range. Nisin activity was determined by the agar diffusion assay utilizing Lactobacillus sake as a sensitive indicator microorganism. Results indicated that nisin partitions preferentially to the micelle rich-phase, despite the surfactant concentration tested, and its antimicrobial activity increases. The successful implementation of this peptide partitioning, from a suspension containing other compounds, represents an important step towards developing a separation method for nisin, and more generally, for other biomolecules of interest.