title: Oil crop biomass residue-based media for enhanced algal lipid production.
abstract: The aim of this study was to evaluate the use of hydrolysates from acid hydrolysis of four different oil crop biomass residues (OCBR) as low cost culture media for algae growth. The one-factor-at-a-time method was used to design a series of experiments to optimize the acid hydrolysis conditions through examining the total nitrogen, total phosphorus, chemical oxygen demand, and ammonia nitrogen in the hydrolysates. The optimal conditions were found to be using 3% sulfuric acid and hydrolyzing residues at 90 °C for 20 h. The hydrolysates (OCBR media) produced under the optimal conditions were used to cultivate the two algae strains, namely UM258 and UM268. The results from 5 days of cultivation showed that the OCBR media supported faster algae growth with maximal algal biomass yield of 2.7 and 3 g/L, respectively. Moreover, the total lipids for UM258 and UM268 were 54 and 35%, respectively, after 5 days of cultivation, which suggested that the OCBR media allowed the algae strains to accumulate higher lipids probably due to high C/N ratio. Furthermore, over 3% of omega-3 fatty acid (EPA) was produced for the two algae strains. In conclusion, OCBR media are excellent alternative for algae growth and have a great potential for large-scale production of algae-based ingredients for biodiesel as well as high-value food and pharmaceutical products.
authors.affiliation: Center for Biorefining, Bioproducts and Biosystems Engineering Department, University of Minnesota, 1390 Eckles Ave, Saint Paul, MN, 55108, USA.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Ma
authors.forename: Wenguang
authors.initials: W
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Min
authors.forename: Yanling
authors.initials: Y
authors.lastname: Cheng
authors.forename: Paul
authors.initials: P
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Shi
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Yuhuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Roger
authors.initials: R
authors.lastname: Ruan
mesh_terms: D056804:Biofuels; D018533:Biomass; D003470:Culture Media / Q000737:chemistry*; D015525:Fatty Acids, Omega-3 / Q000096:biosynthesis*; D006368:Helianthus; D006868:Hydrolysis; D008055:Lipids / Q000096:biosynthesis*; D058086:Microalgae / Q000378:metabolism*; D013025:Glycine max; D013464:Sulfuric Acids / Q000008:administration & dosage; D013696:Temperature; D013997:Time Factors
chemical_list: D056804:Biofuels; D003470:Culture Media; D015525:Fatty Acids, Omega-3; D008055:Lipids; D013464:Sulfuric Acids; C033158:sulfuric acid