Camelina sativa meal hydrolysate as sustainable biomass for the production of carotenoids by Rhodosporidium toruloides
Journal article, 2020

Background: As the circular economy advocates a near total waste reduction, the industry has shown an increased interest toward the exploitation of various residual biomasses. The origin and availability of biomass used as feedstock strongly affect the sustainability of biorefineries, where it is converted in energy and chemicals. Here, we explored the valorization of Camelina meal, the leftover residue from Camelina sativa oil extraction. In fact, in addition to Camelina meal use as animal feed, there is an increasing interest in further valorizing its macromolecular content or its nutri- tional value.

Results: Camelina meal hydrolysates were used as nutrient and energy sources for the fermentation of the carot- enoid-producing yeast Rhodosporidium toruloides in shake flasks. Total acid hydrolysis revealed that carbohydrates accounted for a maximum of 31 ± 1.0% of Camelina meal. However, because acid hydrolysis is not optimal for sub- sequent microbial fermentation, an enzymatic hydrolysis protocol was assessed, yielding a maximum sugar recovery of 53.3%. Separate hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF), and

SSF preceded by presaccharification of Camelina meal hydrolysate produced 5 ± 0.7, 16 ± 1.9, and 13 ± 2.6 mg/L of carotenoids, respectively. Importantly, the presence of water-insoluble solids, which normally inhibit microbial growth, correlated with a higher titer of carotenoids, suggesting that the latter could act as scavengers.

Conclusions: This study paves the way for the exploitation of Camelina meal as feedstock in biorefinery processes. The process under development provides an example of how different final products can be obtained from this side stream, such as pure carotenoids and carotenoid-enriched Camelina meal, can potentially increase the initial value of the source material. The obtained data will help assess the feasibility of using Camelina meal to generate high value- added products.

Camelina meal

Bio-based products

Biorefinery

Renewable resources

Simultaneous saccharification and fermentation (SSF)

Carotenoids

Separate hydrolysis and fermentation (SHF)

Enzymatic hydrolysis

Rhodosporidium toruloides

Author

Stefano Bertacchi

University of Milano-Bicocca

Maurizio Bettiga

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

EviKrets Biobased Processes Consultants

Danilo Porro

University of Milano-Bicocca

Paola Branduardi

University of Milano-Bicocca

Biotechnology for Biofuels

1754-6834 (eISSN)

Vol. 13 1 47

Driving Forces

Sustainable development

Subject Categories

Renewable Bioenergy Research

Chemical Process Engineering

Bioenergy

Areas of Advance

Energy

Health Engineering

DOI

10.1186/s13068-020-01682-3

PubMed

32190112

More information

Latest update

8/28/2020