Effects of light, CO₂ and inhibitors on the current output of biofuel cells containing the photosynthetic organism <i>Synechococcus</i> sp

Abstract

Abstract The current output of the biofuel cells containing a marine alga, Synechococcus sp. and an electron transport mediator, 2‐hydroxy‐1, 4‐naph‐thoquinone (HNQ) was increased under illumination and in the presence of CO 2 . The inhibitory effects of carbonyl cyanide m‐chlorophenylhydrazone (CCCP), 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU), 2,5‐dibromomethylisopropyl‐ p ‐benzoquinone (DBMIB), phenylmercury acetate (PMA) and N,N′‐dicyclohexyl‐carbodiimide (DCCD) on the output current of fuel cells run in the light suggested that HNQ accepts electrons mainly at the site of ferredoxin‐NADP + reductase (FNR) in the electron transfer chain. The inhibition of light‐induced generation of current output by CCCP indicates that the current is derived from photosynthetic oxidation of water. Endogenous glycogen in algae is required to sustain a steady current output from the fuel cells .