Elhalis, H., Helmy, M., Ho, S., Leow, S., Liu, Y., Selvarajoo, K., Chow, Y. (2024). Identifying Chlorella vulgaris and Chlorella sorokiniana as sustainable organisms to bioconvert glucosamine into valuable biomass. Biotechnology Notes, 5, 13–22. https://doi.org/10.1016/j.biotno.2024.01.003
Abstract:
Chitin is a major cell wall component of various organisms such as crustacean shells, filamentous fungi, and insects that is very difficult to degrade in nature. Recently, food-safe biological and chemical processes converting chitin to glucosamine have been developed. Here, we studied microalgae that can uptake glucosamine as vital carbon and nitrogen sources for valuable alternative protein biomass. Utilizing data mining and bioinformatics analysis, we identified 29 species that contain the required enzymes for glucosamine to glucose conversion. The growth performance of the selected strains was examined, and glucosamine was used in different forms and concentrations. Subsequently, pretreatment of glucosamine with hydrolytic enzymes and strain evolution processes were carried out to improve glucosamine utilization. Glucose at a concentration of 2.5 g/L was required to initiate glucosamine metabolic degradation by Chlorella vulgaris and Chlorella sorokiniana. Glucosamine HCL and glucosamine phosphate showed maximum cell counts of about 8.5 and 9.0 log/mL for C. sorokiniana and C. vulgaris, respectively. Enzymatic hydrolysis of glucosamine using α-amylase and amyloglucosidase increased growth performance with C. sorokiniana by about 3 folds. Half-generation time and doubling of the produced dry biomass were observed using adapted strains. In addition, adapted C. sorokiniana was able to tolerate three times glucosamine concentration in the medium. The study illustrated possible strategies for employing C. sorokiniana and C. vulgaris to convert glucosamine-based waste into valuable biomass in a more sustainable way.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This research / project is supported by the A*STAR - Singapore Food Story R&D Programme (1st Alternative Protein Seed Challenge)
Grant Reference no. : W20W2D0017