The Biodegradation of Certain Components of Town Waste by Thermophilic Fungi

Abstract

An investigation to elucidate the possible role played by the
thermophilic fungi in the process of town waste composting was carried
out since previous observations had suggested that several species were
highly cellulolytic but that very few species had ever been isolated from
composting town waste. Biochemical studies on a small town waste windrow
confirmed that a high percentage of cellulose was utilised, and that the
pH of the waste rose to alkaline values during the thermophilic phase of
composting. This suggested that those cellulolytic thermophiles which
chad been isolated from composting town waste were successful in colonising
this substrate because they were able to adapt to environmental parameters
_imposed by such a system, This was partially confirmed by a study of the
cellulolytic activity of the twelve cellulolytic thermophiles in isolation, on
cellulose perfused with pH-buffered salts, by their inter-reactions on
cellulose, and by a study of their Cx cellulase enzymes. The results
indicated that the six cellulolytic thermophiles isolated from composting
town waste could grow, sporulate, produce active cellulase enzymes and
compete together successfully on cellulose under conditions similar to those
imposed by the town waste composting process, Suggestions for future work
were outlined. The activin of the thermophilic fungi towards synthetic
polymers and siketiataies was studied since these materials are found in
intr casi quantities within town waste, Polyethylene and polyvinyl chloride
were non-biodegradable and a process in which these recalcitrant molecules
could be recycled was described. All nineteen thermophiles tested were
shown to actively produce esterase enzymes when grown upon ester
plasticisers, Finally, all thermophilic fungi under test were able to produce
humus substances which were similar in composition to substances isolated
from composted town waste.

Date of Award	1973
Original language	English