Research On Microorganisms And Enzyme Activities During The Initial Stage Of Aerobic Degradation Of Municipal Organic Waste

Vegetable wastes in Hefei agricultural market were composted on bench scale for 6 days, simulating the industrialized composting process according to its temperature change by manually regulating incubator temperature. The initial stage of aerobic composting process was researched and evaluated from the angles of microbiology and enzymology, revealing the inside biochemical mechanisms behind the close correlations between microorganisms, enzyme activities and organic biodegradation. Total microorganism,bacteria,actinomyces and fungi were incubated in 37℃, 45℃and 55℃, respectively. Reducing sugar, lipase activity, protease activity, amylase activity, pectase activity, cellulase activity and xylanase activity were determinated.Results demonstrated: the reached-peak-time of the quantities of 37℃-cultured, 45℃-cultured and 55℃-cultured microorganisms, respectively, were delayed about two days. Composting-temperature-cultured microorganisms, quantitatively indicating the high-low-high, were only those who kept active in whole microbial population. The six hydrolytic enzyme activities decreased with temperature increase and started to rise at the late stage of high temperature. The increase in lipase activity, protease activity, amylase activity, cellulase activity and xylanase activity indicated still immaturity of compost as a result of existence of much substrate.Biodegradation of Organic matters was performed quickly before and after high temperature, whereas slow during high temperature because active microorganisms under high temperature stress reduced the secretion of enzymes. The fermentation temperature slower than 55℃was proved suitable for organic degradation in aerobic composting processs.