Isolation and Selection of Protein-Rich Mutants of Chlorella vulgaris by Fluorescence-Activated Cell Sorting with Enhanced Biostimulant Activity to Germinate Garden Cress Seeds

• Author(s): Trovão, Mafalda ; Schüler, Lisa ; Pedroso, Humberto ; Reis, Ana ; Santo, Gonçalo Espírito ; Barros, Ana ; Correia, Nádia ; Ribeiro, Joana ; Bombo, Gabriel ; Gama, Florinda ; Viana, Catarina ; Costa, Monya M. ; Ferreira, Sara ; Cardoso, Helena ; Varela, João ; Silva, Joana ; Freitas, Filomena ; Pereira, Hugo
• Date: 2024
• Persistent ID: http://hdl.handle.net/10362/180325
• Origin: Repositório Institucional da UNL
• Project/scholarship: info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDP%2F04378%2F2020/PT; info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F04378%2F2020/PT; info:eu-repo/grantAgreement/FCT/Concurso para Atribuição do Estatuto e Financiamento de Laboratórios Associados (LA)/LA%2FP%2F0140%2F2020/PT; info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F04326%2F2020/PT; info:eu-repo/grantAgreement/FCT/Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017%2F2018) - Financiamento Programático/UIDP%2F04326%2F2020/PT; info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/LA%2FP%2F0101%2F2020/PT; info:eu-repo/grantAgreement/FCT/OE/2020.06814.BD/PT; info:eu-repo/grantAgreement/FCT/OE/2020.07229.BD/PT
• Subject(s): biostimulants; fluorescence-activated cell sorting; microalgae; protein; random mutagenesis; selection method; Ecology, Evolution, Behavior and Systematics; Ecology; Plant Science; SDG 2 - Zero Hunger; SDG 8 - Decent Work and Economic Growth
• Document Type: Journal article
• Language: English
• Contributor(s): UCIBIO - Applied Molecular Biosciences Unit; DQ - Departamento de Química; RUN

Description

This research was funded by CRESC Algarve and European Regional Development Fund through the ALG-01-0247-FEDER-069961 PERFORMALGAE project. © 2024 by the authors. Licensee MDPI, Basel, Switzerland.

Microalgae are a promising feedstock with proven biostimulant activity that is enhanced by their biochemical components (e.g., amino acids and phytohormones), which turns them into an appealing feedstock to reduce the use of fertilisers in agriculture and improve crop productivity and resilience. Thus, this work aimed to isolate protein-rich microalgal mutants with increased biostimulant activity. Random mutagenesis was performed with Chlorella vulgaris, and a selection of protein-rich mutants were sorted through fluorescence-activated cell sorting (FACS), resulting in the isolation of 17 protein-rich mutant strains with protein contents 19–34% higher than that of the wildtype (WT). Furthermore, mutant F4 displayed a 38%, 22% and 62% higher biomass productivity, growth rate and chlorophyll content, respectively. This mutant was then scaled up to a 7 L benchtop reactor to produce biomass and evaluate the biostimulant potential of this novel strain towards garden cress seeds. Compared to water (control), the germination index and the relative total growth increased by 7% and 19%, respectively, after the application of 0.1 g L−1 of this bioproduct, which highlights its biostimulant potential.