Integrative platform for the selective recovery of intracellular carotenoids and lipids from: Rhodotorula glutinis CCT-2186 yeast using mixtures of bio-based solvents

Made available in DSpace on 2021-06-25T10:18:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-07 Natural bioactive compounds have been attracting growing interest from the industries as a greeneralternative to synthetic raw materials/products. Rhodotorula glutinis yeast naturally synthesizes added value compounds such as lipids and carotenoids, commonly used for cosmetic, pharmaceutical, and food applications. R. glutinis constitutes a rigid cell-wall structure, requiring energy-saving and efficient cell disruption methods for a sustainable recovery of the intracellular compounds. A simple and ecofriendly technology using mixed bio-based solvents (biosolvents) was evaluated here as an alternative platform to permeabilize yeast cells and to improve the selective recovery of β-carotene, torularhodin, torulene and lipids. The extraction ability of pure and solvent mixtures (methanol, ethanol, ethyl acetate, isopropanol, cyclohexane and 2-methyl tetrahydrofuran) was initially screened, demonstrating the clear impact of using mixtures to improve the extraction yields (up to three-fold increase). After identifying ethyl acetate/ethanol/water as the solvent mixture with a greater capacity to extract carotenoids and lipids, the selective recovery of carotenoids and lipids was enhanced by optimizing the solvent mixture composition ratio. Envisioning the industrial application, an integrated biosolvent-based downstream platform was designed. Two different strategies were investigated to further isolate carotenoids and lipids from R. glutinis biomass and to recycle the ethyl acetate/ethanol/water mixture: (i) precipitation using cold acetone; (ii) sequential liquid-liquid extraction. The integrated process for each strategy was compared with a conventional extraction procedure in terms of recovery efficiencies and its environmental impact. Regardless of the strategy, it is shown that the mixture of ethyl acetate, ethanol and water (15/27/58% w/w) can be reused up to three consecutive extractive cycles, ensuring high extraction efficiency yields, while decreasing the process carbon footprint by about 75% compared to the conventional method. Department of Engineering Bioprocesses and Biotechnology School of Pharmaceutical Sciences Saõ Paulo State University (UNESP) CICECO Aveiro Institute of Materials Department of Chemistry University of Aveiro Department of Marine Faculty of Fisheries and Marine Universitas Airlangga Jalan, Mulyorejo Kampus C CESAM Centre for Environmental and Marine Studies Department of Environment and Planning University of Aveiro Univ Coimbra CIEPQPF Department of Chemical Engineering, Rua Sílvio Lima Pólo II-Pinhal de Marrocos Department of Engineering Bioprocesses and Biotechnology School of Pharmaceutical Sciences Saõ Paulo State University (UNESP)