Maximizing the utilization of Laminaria japonica as biomass via improvement of alginate lyase activity in a two‐phase fermentation system

Abstract

Brown seaweed contains up to 67% of carbohydrates by dry weight and presents high potential as a polysaccharide feedstock for biofuel production. To effectively use brown seaweed as a biomass, degradation of alginate is the major challenge due to its complicated structure and low solubility in water. This study focuses on the isolation of alginate degrading bacteria, determining of the optimum fermentation conditions, as well as comparing the conventional single fermentation system with the two-phase fermentation system which is separately using alginate and mannitol extracted from Laminaria japonica. Maximum yield of organic acids production and volatile solids reduction obtained were 0.516 g/g and 79.7%, respectively, using the two-phase fermentation system in which alginate fermentation was carried out at pH 7 and mannitol fermentation at pH 8. The two-phase fermentation system increased the yield of organic acids production by 1.14 times and led to a 1.45-times reduction of VS when compared to the conventional single fermentation system at pH 8. The results show that the two-phase fermentation system improved the utilization of alginate by separating alginate from mannitol leading to enhanced alginate lyase activity.

Editorial: Bioengineering for a better quality of life

“…Pathway engineering, knockout and metabolic engineering approaches are used to optimize cells and control the overproduction of target products [7–12]. Novel trends searching for new protein sources and biomass are covered by Sari et al in their review on plant protein refineries [13] and by Oh et al who describe a two phase fermentation system to maximize the utilization of Laminaria japonica as a biomass source [14]. Biochemical engineering is also an important field to enable cell therapies.…”