Biological production of kojic acid from sugar beet pulp with enhanced recovery via salt-assisted liquid–liquid extraction
Year: 2026
Type: article
Abstract: Kojic acid (KA) is a high-value fungal secondary metabolite used in cosmetics and pharmaceuticals, but commercial production is limited by costly substrates and inefficient recovery. This study developed an integrated bioprocess for KA production by Aspergillus flavus . Agitated cultivation with glucose as the optimal carbon source markedly improved biosynthesis. An initial glucose concentration of 80 g/L, corn steep liquor as the nitrogen source, and an initial pH of 3.6 provided the highest performance in shake-flask cultivation, producing 47.0 g/L KA with a yield of 0.61 g/g. Under batch bioreactor cultivation, these conditions were successfully translated, increasing KA production to 52.8 g/L with a yield of 0.66 g/g. Fed-batch cultivation using pure glucose further increased KA production to 80.2 g/L. Replacement of pure glucose with non-detoxified glucose-rich SBP hydrolysate enabled efficient co-utilization of mixed sugars, producing 38.0 g/L KA in batch culture and 72.3 g/L in fed-batch fermentation, representing one of the highest reported KA titers from a lignocellulosic hydrolysate. For downstream processing, ethyl acetate extraction with 35% ( w / v ) ammonium sulphate significantly enhanced KA recovery, increasing extraction yields by 27% and 62% for glucose- and SBP hydrolysate-based fermentation broths, respectively, at >99% purity. These findings demonstrate the potential of integrating renewable SBP hydrolysate with an intensified recovery strategy for KA bioproduction, while highlighting the need for further process and product-safety validation before downstream application.
Source: Chemical Engineering Journal
Institution: Cranfield University
Language: English
Subfield: Biotechnology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,830
OpenAlex ID: W7214800593