Title: Improving biomass and lipid yields of Desmodesmus armatus and Chlorella vulgaris through mutagenesis and high-throughput screening

Abstract

Advancement of microalgae for use as biofuel feedstock depends on bioprospecting novel strains and then applying classical strain improvement techniques to enhance desirable traits. Here we successfully demonstrate this approach using two novel strains of green algae, identified as Desmodesmus armatus and Chlorella vulgaris, to improve biomass and lipid yields. UV irradiation was utilized to generate random mutations and the resulting populations were analyzed via flow cytometry to quantify lipid fluorescence while enriching for high lipid variants using fluorescence activated cell sorting. Secondary screening was performed via in situ fluorescence staining to identify the single highest lipid producing mutants from each strain. This approach produced a Desmodesmus armatus mutant that exhibited both increased biomass productivity and higher lipid content, which doubled lipid yield from the culture. The resulting Chlorella vulgaris mutant exhibited an increase in growth only, resulting in a 33% increase in lipid yield.

Authors:

Smalley, Tressa  ^[1];

• Search DOE PAGES for author "Smalley, Tressa"
• Search DOE PAGES for ORCID "0000-0001-9938-0274"

Fields, Francis J.  ^[1];

• Search DOE PAGES for author "Fields, Francis J."
• Search DOE PAGES for ORCID "0000-0003-1152-2405"

Berndt, Anthony J. E. ^[1]; Ostrand, Joseph T. ^[1]; Heredia, Vanessa  ^[1];

• Search DOE PAGES for author "Heredia, Vanessa"
• Search DOE PAGES for ORCID "0000-0002-4057-6237"

Mayfield, Stephen P. ^[1]

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+ Show Author Affiliations

1. Univ. of California, San Diego, La Jolla, CA (United States)

Publication Date:

Wed Sep 23 00:00:00 EDT 2020

Research Org.:

Global Algae Innovations, San Diego, CA (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE)

Contributing Org.:

Global Algae Innovations

OSTI Identifier:

1712419

Alternate Identifier(s):

OSTI ID: 1664575; OSTI ID: 1712417

Report Number(s):

DOE-GAI-7689-1
Journal ID: ISSN 0961-9534

Grant/Contract Number:  

EE0007689

Resource Type:

Accepted Manuscript

Journal Name:

Biomass and Bioenergy

Additional Journal Information:

Journal Volume: 142; Journal Issue: 105755; Journal ID: ISSN 0961-9534

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

09 BIOMASS FUELS; 59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES; Microalgae; mutagenesis; strain improvement; FACS; Nile; red; biofuel