title: Effect of ultraviolet radiation on photosynthesis, biomass, and fatty acid content and profile of a Scenedesmus rubescens-like microalga.
abstract: The effects of ultraviolet radiation (UVR) and nitrogen (NaNO(3)) concentration on photosynthesis, biomass, and fatty acid content and profile of a Scenedesmus rubescens-like microalga were measured in an outdoor 8-day culture study. UV-induced photoinhibition decreased from 42.6% to 3.5%, in the presence of 75 mg/L NaNO(3) (HN) and from 52.9% to 22.6% in the presence of 7.5mg/L NaNO(3) (LN) nitrogen concentration, respectively. The concentrations of UV-absorbing compounds increased 4.3 and 4.9 times under HN and LN, respectively. Biomass accumulation was suppressed (10.7%) by UVR under HN, but not under LN conditions. Carotenoid content decreased from 1.05 ± 0.06 to 0.96 ± 0.15 (with UV radiation) and to 0.91 ± 0.07 (without UV radiation), respectively, under HN, while it decreased to 0.05 ± 0.04 (with UV radiation) and to 0.11 ± 0.08 (without UV radiation), respectively, under LN. The content of C18:1n9 fatty acids increased by about 430%, whereas that of C18:3n3 decreased by about 65% in both radiation treatments during nitrogen starvation. The results showed that the absence of UVR screening does not change the fatty acid content and profile of S. rubescens-like algae cultivated outdoors under HN and LN conditions.
authors.affiliation: Vero Beach Marine Laboratory, Florida Institute of Technology, Vero Beach, FL 32963, USA. liping@stu.edu.cn
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Junda
authors.initials: J
authors.lastname: Lin
mesh_terms: D018533:Biomass; D005227:Fatty Acids / Q000032:analysis*; D010788:Photosynthesis; D044444:Scenedesmus / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D005227:Fatty Acids