peptones and Hypoxia

Alcaligenes faecalis kw-A selected for possessing good denitrification efficiency was used for biofilm development. The biofilm could be developed on a glass surface within 12 hr when 5%, Ix 10(8) cells/ml was used as inoculum. The microcolonies were seen in 6 hr and glycocalyx in 9 hr stage. At 24 hr the biofilm was developed fully and hence was visualised as dense mass. The biofilm protein content showed 48.5% increase in shake flask than in static condition. The exopoplymer is produced in larger amounts in biofilm as compared to the suspended cells. Also, its amount was more by 43% in the biofilm produced in shake flask condition than in static condition. The biofilm could remove 95% nitrate from nitrate-rich effluent in a bench-scale process in 36 hr. The attached growth technique demonstrated here can be utilised to study the effect of favourable as well as adverse conditions on the denitrification efficiency of a culture. The ultimate application of a denitrifying biofilm would be in attached growth or biofilm reactor.

Topics: Alcaligenes faecalis; Animals; Biochemistry; Biofilms; Cattle; Glass; Glycocalyx; Hydrogen-Ion Concentration; Hypoxia; Microscopy; Microscopy, Phase-Contrast; Nitrates; Nitrogen; Peptones; Polysaccharides; Temperature; Time Factors

Topics: Acetylcholine; Adrenal Glands; Adrenal Medulla; Angiotensins; Calcium; Calcium, Dietary; Catecholamines; Cystamine; Histamine; Hypoxia; In Vitro Techniques; Magnesium; Nicotine; Peptones; Perfusion; Pharmacology; Pilocarpine; Potassium; Rats; Research; Reserpine; Sodium