1 research outputs found
Utilization of Sweet Sorghum Juice for the Production of Astaxanthin as a Biorefinery Co-Product by <i>Phaffia rhodozyma</i>
This work investigates
cultivating the red-pigmented yeast Phaffia rhodozyma in sweet sorghum juice (SSJ) to
assess the production of astaxanthin as a potential biorefinery co-product.
Shake flask cultures on defined sugar medium indicated that all three
sugars (sucrose, glucose, and fructose) could be consumed with adequate
nitrogen and nutrient supplementation. Only modest biomass growth
and astaxanthin production could be achieved in SSJ without nitrogen
supplementation; however, combining nitrogen supplementation with
yeast extract in diluted SSJ could metabolize all sugars present in
168 h. A 2 L bioreactor trial with full strength (i.e., undiluted)
SSJ produced up to 29 g/L of biomass, 65.4 mg/L of astaxanthin, an
overall cell astaxanthin content of 2.49 mg astaxanthin/g dry cell
mass, and a volumetric astaxanthin productivity of 0.389 mg/L/h after
168 h of cultivation. Further process optimization is needed since
glucose metabolism was incomplete in undiluted SSJ