| Title | Effect of light and temperature on biomass, photosynthesis and capsular polysaccharides in cultured phototrophic biofilms |
| Abstract | Phototrophic biofilms seem to be suitable candidates
for tertiary wastewater treatment due to their high
uptake capacity for nutrients and other pollutants, also
taking into account the time and cost savings derived from
easy procedures for biomass harvesting. Biomass accrual,
structure, and physiology of biofilms affect the efficiency of
nutrient removal by its microbial community. Here, we
construct a biofilm consisting of a cyanobacterium Synechocystis
sp. and the green alga Chlorococcum sp. and
determine the effect of combined variations of irradiance
and temperature on the biofilm structure and function. The
two species were isolated from phototrophic biofilms
naturally developing in an Italian wastewater treatment
plant and grown in a microcosm designed for biofilm
investigations. Phototrophic biomass accumulation, percent
species composition, photosynthetic response and the
amount and composition of capsular polysaccharides
(CPS), including anionic residues, are reported. The results
showed that biofilm development required relatively moderate
irradiances (60 ?mol photons m-2 s-1) below which
development was arrested. Both light and temperature had a strong effect on the composition of each species to the
biofilm. The CPS compositions also changed with temperature,
light and species composition. The CPS of the greenalgal-
dominated biofilm had the higher uronic acid content
indicating a potential to exploit green algae in the treatment
of waste contaminated with heavy metals. Given the
knowledge of the response of certain species to light and
temperature combinations, it may be possible to construct
biofilms of known species and CPS composition to use
them for specific applications. |
| Source | Journal of applied phycology (Dordr., Online) |
| Keywords | Phototrophic biofilm .Water treatment . Matrix . Capsular polysaccharides . Uronic acids . Photosynthesis |
| Journal | Journal of applied phycology (Dordr., Online) |
| Editor | Kluwer, Dordrecht, Paesi Bassi |
| Year | 2012 |
| Type | Articolo in rivista |
| Authors | Francesca Di Pippo & Neil Tomas William Ellwood & Antonella Guzzon & Luisa Siliato & Ernesto Micheletti & Roberto De Philippis & Patrizia B. Albertano |
| Text | 349270 2012 Phototrophic biofilm .Water treatment . Matrix . Capsular polysaccharides . Uronic acids . Photosynthesis Effect of light and temperature on biomass, photosynthesis and capsular polysaccharides in cultured phototrophic biofilms Francesca Di Pippo Neil Tomas William Ellwood Antonella Guzzon Luisa Siliato Ernesto Micheletti Roberto De Philippis Patrizia B. Albertano Department of Geological Sciences, University of Rome Roma Tre , Rome, Italy Department of Biology, University of Rome Tor Vergata , via della Ricerca scientifica s.n.c, 00133, Rome, Italy Department of Agricultural Biotechnology, University of Florence, Florence, Italy IRSA CNR Phototrophic biofilms seem to be suitable candidates for tertiary wastewater treatment due to their high uptake capacity for nutrients and other pollutants, also taking into account the time and cost savings derived from easy procedures for biomass harvesting. Biomass accrual, structure, and physiology of biofilms affect the efficiency of nutrient removal by its microbial community. Here, we construct a biofilm consisting of a cyanobacterium Synechocystis sp. and the green alga Chlorococcum sp. and determine the effect of combined variations of irradiance and temperature on the biofilm structure and function. The two species were isolated from phototrophic biofilms naturally developing in an Italian wastewater treatment plant and grown in a microcosm designed for biofilm investigations. Phototrophic biomass accumulation, percent species composition, photosynthetic response and the amount and composition of capsular polysaccharides CPS , including anionic residues, are reported. The results showed that biofilm development required relatively moderate irradiances 60 mol photons m 2 s 1 below which development was arrested. Both light and temperature had a strong effect on the composition of each species to the biofilm. The CPS compositions also changed with temperature, light and species composition. The CPS of the greenalgal dominated biofilm had the higher uronic acid content indicating a potential to exploit green algae in the treatment of waste contaminated with heavy metals. Given the knowledge of the response of certain species to light and temperature combinations, it may be possible to construct biofilms of known species and CPS composition to use them for specific applications. Published version Di Pippo et al. 2012 Di_Pippo_et_al_2012_JAP.pdf Articolo in rivista Kluwer 1573 5176 Journal of applied phycology Dordr., Online Journal of applied phycology Dordr., Online J. appl. phycol. Dordr., Online Journal of applied phycology. Dordr., Online francesca.dipippo DI PIPPO FRANCESCA |
