SYNERGETIC FLOCCULATION OF THE BIOFLOCCULANT FIX EXTRACELLULARLY PRODUCED BY NOCARDIA AMARAE

Abstract

The fractionation of bioflocculant FIX produced by Nocardia amarae YK1 revealed that the flocculant was a mixture of more than three substances. Although individual fractions did not exhibit the ability of flocculation at pH 5 to 7, synergetic flocculation was observed at pH 7 after mixing the fractions. Infrared spectrophotometry suggested that the chief components of fractions might be peptides. Enzymatic digestion of peptide moiety resulted in disappearance of flocculation activity. One of the ingredients of FIX carried high contents of glycine (25.6%), alanine (13.8%), and serine (12.3%), of which R groups were relatively small.