title: Effect of light with different wavelengths on Nostoc flagelliforme cells in liquid culture.
abstract: The effects of lights with different wavelengths on the growth and the yield of extracellular polysaccharides of Nostoc flagelliforme cells were investigated in a liquid cultivation. N. flagelliforme cells were cultured for 16 days in 500 ml conical flasks containing BG11 culture medium under 27 micromol·m-2·s-1 of light intensity and 25 degrees C on a rotary shaker (140 rpm). The chlorophyll a, phycocyanin, allophycocyanin, and phycoerythrin contents in N. flagelliforme cells under the lights of different wavelengths were also measured. It was found that the cell biomass and the yield of polysaccharide changed with different wavelengths of light. The biomass and the yield of extracellular polysaccharides under the red or violet light were higher than those under other light colors. Chlorophyll a, phycocyanin, and allophycocyanin are the main pigments in N. flagelliforme cells. The results showed that N. flagelliforme, like other cyanobacteria, has the ability of adjusting the contents and relative ratio of its pigments with the light quality. As a conclusion, N. flagelliforme cells favor red and violet lights and perform the complementary chromatic adaptation ability to acclimate to the changes of the light quality in the environment.
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Bioengineering, Tianjin University of Science and Technology, Tianjin 300457, PR China. yjdai@126.com
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Dai
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Shu-Mei
authors.initials: SM
authors.lastname: Wei
authors.forename: Nan
authors.initials: N
authors.lastname: Chen
authors.forename: Yu-Peng
authors.initials: YP
authors.lastname: Xiao
authors.forename: Zhi-Lei
authors.initials: ZL
authors.lastname: Tan
authors.forename: Shi-Ru
authors.initials: SR
authors.lastname: Jia
authors.forename: Nan-Nan
authors.initials: NN
authors.lastname: Yuan
authors.forename: Ning
authors.initials: N
authors.lastname: Tan
authors.forename: Yi-Jie
authors.initials: YJ
authors.lastname: Song
mesh_terms: D018533:Biomass; D003470:Culture Media / Q000737:chemistry; D008027:Light; D046937:Nostoc / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects*; D010100:Oxygen / Q000378:metabolism; D010860:Pigments, Biological / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D013696:Temperature
chemical_list: D003470:Culture Media; D010860:Pigments, Biological; D011135:Polysaccharides, Bacterial; D010100:Oxygen