title: Biomass and pigments production in photosynthetic bacteria wastewater treatment: Effects of photoperiod.
abstract: This study aimed at enhancing the bacterial biomass and pigments production in together with pollution removal in photosynthetic bacteria (PSB) wastewater treatment via using different photoperiods. Different light/dark cycles and light/dark cycle frequencies were examined. Results showed that PSB had the highest biomass production, COD removal and biomass yield, and light energy efficiency with light/dark cycle of 2h/1h. The corresponding biomass, COD removal and biomass yield reached 2068mg/L, 90.3%, and 0.38mg-biomass/mg-COD-removal, respectively. PSB showed higher biomass production and biomass yield with higher light/dark cycle frequency. Mechanism analysis showed within a light/dark cycle from 1h/2h to 2h/1h, the carotenoid and bacteriochlorophyll production increased with an increase in light/dark cycle. Moreover, the pigment contents were much higher with lower frequency of 2-4 times/d.
authors.affiliation: School of Environment & Natural Resource, Renmin University of China, 59 Zhongguancun Street, Beijing 100872, China. Electronic address: zqq2012@126.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China. Electronic address: panyue_zhang@bjfu.edu.cn.
authors.forename: Panyue
authors.initials: P
authors.lastname: Zhang
authors.affiliation: School of Environment & Natural Resource, Renmin University of China, 59 Zhongguancun Street, Beijing 100872, China. Electronic address: zgm@ruc.edu.cn.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zhang
authors.affiliation: School of Environment & Natural Resource, Renmin University of China, 59 Zhongguancun Street, Beijing 100872, China. Electronic address: pengmeng2010@gmail.com.
authors.forename: Meng
authors.initials: M
authors.lastname: Peng
mesh_terms: D049109:Cell Proliferation / Q000502:physiology / Q000528:radiation effects; D008027:Light; D058433:Photobioreactors / Q000382:microbiology; D017440:Photoperiod; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects; D010860:Pigments, Biological / Q000096:biosynthesis* / Q000302:isolation & purification; D011829:Radiation Dosage; D012241:Rhodopseudomonas / Q000502:physiology / Q000528:radiation effects; D062065:Wastewater / Q000032:analysis / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D010860:Pigments, Biological; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Light/dark cycle; Photoperiod; Photosynthetic bacteria; Photosynthetic pigments