ABSTRACT
Alginate oligosaccharides (AOS) showed various biological activities. Traditional protocol for producing AOS was a multiple-step and high-pollution procedure. In this study, a rapid and efficient AOS producing method was developed directly from Laminaria japonica. Natural sun-dried L. japonica with a feed ratio of 1:7 (w/v) was pretreated using cellulase with a dry weight of 3%, for releasing the fermentable sugars (8.5â¯g/L glucose and 15.2â¯g/L mannitol). Then, the engineered yeast Yarrowia lipolytica strain with alginate lyase activity was grown using an algae-based medium. After fermentation for 72â¯h, glucose and mannitol were completely consumed, and 71.8â¯mM AOS was extracted from the fermentation supernatant. The degree of polymerization (DP) was ranging from 2 to 3. The recovery yield of AOS was about 91.7%. The purity of the extracted AOS was 92.6%. Overall, our work provided new insights for the development of green biotechnologies for oligosaccharide production from seaweed.