Biomaterial Database

Heterotrophic growth and nitrogen fixation in the filamentous blue-green alga Anabaena sp. 1981

J Sahu, and S P Adhikary

Experiments were conducted to study the effect of five different organic substrates viz. lactose, fructose, mannose, xylose and sodium acetate on the heterotrophic growth characteristics with emphasis on growth, pigment composition, heterocyst frequency and nitrogen fixation of Anabaena sp. under light and dark conditions. Lactose was found to be the best carbon source to support the heterotrophic growth of the alga. Phycoerythrin pigments were synthesized in photoheterotrophic cultures but pigment production was not observed in dark-grown cultures. The alga fixed nitrogen to a limited extent in the dark in pure inorganic medium. But when suitable organic substrates were supplemented, appreciable nitrogen fixation was observed in dark heterotrophic as well as in photoheterotrophic cultures.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D009586	Nitrogen Fixation	The process in certain BACTERIA; FUNGI; and CYANOBACTERIA converting free atmospheric NITROGEN to biologically usable forms of nitrogen, such as AMMONIA; NITRATES; and amino compounds.	Diazotrophy,Diazotrophic Activity,Dinitrogen Fixation,N2 Fixation,Activities, Diazotrophic,Activity, Diazotrophic,Diazotrophic Activities,Fixation, Dinitrogen,Fixation, N2,Fixation, Nitrogen
D003624	Darkness	The absence of light.	Darknesses
D000085	Acetates	Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.	Acetate,Acetic Acid Esters,Acetic Acids,Acids, Acetic,Esters, Acetic Acid
D000458	Cyanobacteria	A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.	Algae, Blue-Green,Blue-Green Bacteria,Cyanophyceae,Algae, Blue Green,Bacteria, Blue Green,Bacteria, Blue-Green,Blue Green Algae,Blue Green Bacteria,Blue-Green Algae
D050260	Carbohydrate Metabolism	Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.	Metabolism, Carbohydrate