Heterotrophic cultivation of Galdieria sulphuraria under non-sterile conditions in digestate and hydrolyzed straw. (October 2021)

• Record Type: Journal Article
• Authors: Pleissner, Daniel; Lindner, Astrid Victoria; Händel, Nicole
• Is Part Of: Bioresource technology. Volume 337(2021)
• Publication Date: 2021-10
• Subjects: Straw -- Digestate -- Anaerobic digestion -- Hydrolysis -- Agricultural residues; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2021.125477
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: - G. sulphuraria cultivation occurred on medium made from agricultural residues. - Digestate was revealed as superior nitrogen source for G. sulphuraria. - Proteolytic treatment of digestate led to increased yield of biomass and growth rate. - Produced biomass was with around 40% (w/w) rich in protein. Abstract: Non-sterile heterotrophic cultivation of Galdieria sulphuraria in presence of digestate as well as straw after hydrolysis was investigated. G. sulphuraria can be grown in pure digestate at rates of 0.9 day −1 with glucose. However, a proteolytic treatment of digestate resulted in increased growth rates (1.2 day −1 ) and doubled cell concentrations. Furthermore, G. sulphuraria can utilize glucose obtained after straw hydrolysis. Biomass yields in glucose limited cultures were around 0.9 g per g glucose, while only 0.2 g biomass was formed per g glucose in glucose sufficient cultures. Biomass composition (w/w) of G. sulphuraria grown in digestate supplemented with straw hydrolysate consisted of 20% carbohydrates, 37% proteins and 3% lipids. This study revealed the potential to utilize agricultural waste streams to form algal biomass rich in proteins and may pave the way to novel utilization strategies to be implemented in rural areas.