Biological ethanol fuel can generally be produced from land plants that produce materials such as sugar, starch, and lignocellulosic biomass. But a new biomass is required for supplying the raw material because the use of land plants becomes a problem due to competition with food resource uses of those plants and the accompanying rise in price of foods.
Brown seaweed contains up to 67% carbohydrates by dry weight, which includes materials such as alginate, laminaran, mannitol, etc., and does not contain lignin. Brown seaweed grow fast and has high production rates per unit area, its cultivation has been extensively studied, and its annual production was reported to be 7.5 – 8.0 million tons. Recently, brown seaweed have been considered as feedstock for bioethanol production, an interest in the application of brown seaweed to biotechnology fields has been rapidly increasing.
In this present work, a kind of brown seaweed, Saccharina japonica was fractionated to extract alginic acid under the various reaction temperatures, reaction times and catalyst concentrations for the production of bioethanol, and to develop an integrated process conducting alginic acid extraction and pretreatment of S. japonica simultaneously via glucan amount analysis and enzyme hydrolysis on the remaining solid after alginic acid extraction.