Pulp and paper industry side-stream materials as feed for the oleaginous yeast species Lipomyces starkeyi and Rhodotorula toruloidesShow others and affiliations
2025 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669Article in journal (Refereed) Epub ahead of print
Abstract [en]
The pulp and paper industry in Sweden annually produce millions of tons of side-stream materials as black liquor, pulp and paper mill sludge, sulfite liquor and lignosulfonate. These lignocellulosic based materials can be more utilized today in biorefinery processes with microorganisms to produce high-value products as lipids, proteins and biofuels. In this work, we used five side-stream materials as carbon source in fermentation with two oleaginous yeasts, Lipomyces starkeyi and Rhodotorula toruloides. We analyzed lipid production, fatty acid profiles, inhibitors, phenolics, free sugars and metals before and after batch fermentation in 2 L bioreactors. Steam-exploded hardwood media was used as reference as it's known to be a good substrate for the oleaginous yeast species and after fermentation the lipid yield for R. toruloides was 17 % (w/w) and for L. starkeyi 13 % (w/w). The side-stream materials contained less than 30 % of free sugar compared to the reference media and the total lipid yield was thus less than 2.7 %, (w/w). R. toruloides utilized various sugars during fermentation and L. starkeyi mostly consumed glucose and xylose. Both yeast species also showed a possible ability to utilize various phenolics indicating their metabolic potential to convert depolymerized lignin along with wood-based sugars to lipids and proteins.
Place, publisher, year, edition, pages
Walter de Gruyter GmbH , 2025.
Keywords [en]
Fatty acid methyl esters (FAMEs) analysis, fermentation, industrial waste, lipid production, oleaginous yeast
National Category
Bioprocess Technology
Identifiers
URN: urn:nbn:se:miun:diva-53611DOI: 10.1515/npprj-2024-0039ISI: 001392576900001Scopus ID: 2-s2.0-85215954607OAI: oai:DiVA.org:miun-53611DiVA, id: diva2:1928067
2025-01-162025-01-162025-02-04Bibliographically approved