Green Technology Applied to the Purification and Encapsulation of Microalgae Biopigments Using Nanostructured Colloidal Systems.

• Grant number: 25/08056-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2025
• End date: July 31, 2026
• Field of knowledge: Engineering - Chemical Engineering - Chemical Technology
• Principal Investigator: Patricia Caroline Molgero Da Rós
• Grantee: Marina Ferraro Brocanelli
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil

Abstract

Biopigments obtained from microalgal biomass, such as chlorophylls and carotenoids, have attracted growing interest in the cosmetic and pharmaceutical industries due to their antioxidant and antimicrobial properties. However, their application is limited by intrinsic characteristics, such as low solubility in aqueous media, physicochemical instability, and reduced bioavailability, which compromise their effectiveness in bioactive formulations. In this context, the use of purification and nanoencapsulation methodologies presents a promising strategy to overcome these limitations. This project proposes to evaluate the extraction and purification processes of biopigments from microalgal biomass previously dehydrated by spray drying, as well as their subsequent purification and nanoencapsulation in micellar formulations, using aqueous two-phase systems (ATPS) as a sustainable technological approach. The microalga Dunaliella salina will be cultivated in Guillard f/2 medium in bubble column photobioreactors. The resulting biomass will be recovered through flocculation and subjected to spray drying, using the best previously established operational conditions (130 ºC and an air flow rate of 1.4 m³/min). Subsequently, the extraction and purification processes of the target biopigments (i.e., chlorophylls and carotenoids) will be carried out using ATPS composed of amphiphilic copolymers, replacing traditional extraction with volatile organic solvents, aiming for lower environmental impact, greater selectivity, economic feasibility, and preservation of the structural integrity of the target compounds. The purified biopigments will be nanoencapsulated in polymeric micelles-self-organizing structures capable of protecting bioactive compounds against degradation processes, while enhancing their solubility and stability. The central contribution of this project will be the development of an innovative and environmentally friendly platform for the purification and nanoencapsulation of biopigments extracted from microalgae, aiming at the formulation of products with potential applications in the cosmetic and pharmaceutical industries. Additionally, the execution of this project will contribute to the strengthening of strategic research lines in the Department of Chemical Engineering at the School of Engineering of Lorena (EEL/USP), aligning with the principles of innovation and sustainability advocated by FAPESP.