Towards New-Biomaterial Produced by Microorganism-Bioflocculant and Bioabsorbent-

Abstract

Rhodococcus erythropolis produces a kind of microbial flocculant. This bioflocculant was able to efficiently flocculate all the suspended solids tested in an aqueous solution. Among those tested were microorganisms such as E. coli. and baker's yeast, activated sludge, algae, kaolin clay, muddy water, river bottom sediment, ash and charcoal powder. The bioflocculant NOC-1 from Rhodococcus erythropolis has a wide flocculating activity against both organic and inorganic materials.
From an aqu eous solution of a water-soluble pigment, removal of the water-soluble pigment was attained by the bioflocculant NOC-1. The bioflocculant NOC-1 was able to efficiently flocculate and precipitate the soluble pigment in an aqueous solution tested. Among those efficiently tested were black ink, melanoidin pigment (blackish brown pigment) and black colored pigment of the black liquor of pulping industry.
Culture conditions for producing the bioflocculant w ere also tested. More than 90% of the flocculating activity was found in the culture broth and less than 10% in the cells.
This bioflocculant was purified, and was found to be composed mainly of p rotein. This bioflocculant is biodegradable flocculant which causes no problem of environmental pollution.
The microbial Alcaligenes latus produces a super bioabsorbent which can absorb u p to 1000times of water to its own weight about 5 times greater than currently available synthetic superabsorbents used in sanitary protection and baby diaper products.
Saline absorption rate is very high when compared with s ynthetic polymers and water retention in dry environments is also superior. This bioabsorbent may be environmentally safe for almost all applications, even those such as preventing drying out of desert soil and so on.