TY - JOUR
T1 - Predicting Dissolved Inorganic Carbon in Photoautotrophic Microalgae Culture via the Nitrogen Source
AU - Nguyen, Binh T.
AU - Rittmann, Bruce
N1 - Publisher Copyright:
© 2015 American Chemical Society.
PY - 2015/7/28
Y1 - 2015/7/28
N2 - Dissolved inorganic carbon (DIC) and pH are key factors that control the growth rate of microalgae growing photoautotrophically. Being able to quantify how DIC and pH independently affect growth kinetics requires a means to control each parameter independently. In this study, we used the Proton Condition (PC) to develop means to control pH and DIC independently. Using the PC, we found that different N sources systematically affect the alkalinity and the DIC in distinct ways. With pH controlled at a fixed level by CO2 addition, using nitrate as the N source increased the alkalinity and DIC concentration in proportion to the increase in biomass concentration. In contrast, using ammonium caused the alkalinity and DIC to decline, while using ammonium nitrate left the DIC nearly unchanged. Experiments with a model photoautotroph cyanobacterium, Synechocystis sp. PCC 6803, in batch experiments with modified BG-11 media and a pH-stat confirmed all of the DIC predictions of the PC-based model. Thus, this study provides a mechanistic basis for managing the DIC for photoautotrophic cultures through the N source. In particular, using ammonium nitrate makes it possible to control DIC and pH independently in a pH-stat.
AB - Dissolved inorganic carbon (DIC) and pH are key factors that control the growth rate of microalgae growing photoautotrophically. Being able to quantify how DIC and pH independently affect growth kinetics requires a means to control each parameter independently. In this study, we used the Proton Condition (PC) to develop means to control pH and DIC independently. Using the PC, we found that different N sources systematically affect the alkalinity and the DIC in distinct ways. With pH controlled at a fixed level by CO2 addition, using nitrate as the N source increased the alkalinity and DIC concentration in proportion to the increase in biomass concentration. In contrast, using ammonium caused the alkalinity and DIC to decline, while using ammonium nitrate left the DIC nearly unchanged. Experiments with a model photoautotroph cyanobacterium, Synechocystis sp. PCC 6803, in batch experiments with modified BG-11 media and a pH-stat confirmed all of the DIC predictions of the PC-based model. Thus, this study provides a mechanistic basis for managing the DIC for photoautotrophic cultures through the N source. In particular, using ammonium nitrate makes it possible to control DIC and pH independently in a pH-stat.
UR - http://www.scopus.com/inward/record.url?scp=84939620299&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84939620299&partnerID=8YFLogxK
U2 - 10.1021/acs.est.5b01727
DO - 10.1021/acs.est.5b01727
M3 - Article
C2 - 26218191
AN - SCOPUS:84939620299
SN - 0013-936X
VL - 49
SP - 9826
EP - 9831
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 16
ER -