Chelating, film-forming, and coagulating ability of the chitosan-glucan complex from Aspergillus niger industrial wastes.

Waste mycelia of Aspergillus niger from a citric acid production plant are simply treated with boiling 30-40% NaOH aqueous solutions for 4-6 hr to obtain the insoluble chitosan-glucan complex whose infrared, ESR, and x-ray diffraction spectra are reported. A number of transition- and post-transition-metal ions are chelated and collected by chitosan-glucan with higher yields than by animal chitosan. Immediate flocculation occurs upon mixing chitosan-glucan dispersions with alginate and polymolybdate solutions. Membranes are also obtained from chitosan-glucan dispersions in acetic acid or in chloral and dimethyl formamide mixtures.