EFFICIENCY OF USING GALLERIA MELLONELLA L. (LEPIDOPTERA: PYRALIDAE) FOR WASTE PROCESSING OF SYNTHETIC POLYMERS

Abstract

The problem of waste processing of synthetic polymers makes scientific society look for biodestructors that can digest them. Recently there have appeared some studies that claimed that caterpillars Galleria mellonella L. can influence the integrity of synthetic polymers. In terms of evolution, this species is related to beehives and can digest bee wax. The capability of this insect to digest polyethylene is still under issue. During the research, it was analyzed how the addition of polyethylene to the artificial nutrient medium affects the biological parameters of Pyralidae when cultured in the laboratory. It was shown that adding polyethylene to the standard nutrient medium in proportions of 1/4 та 1/3 does not influence the biological parameters of the species. The viability of caterpillars and chrysalides stays within the control framework. Adding polyethylene to the artificial nutrient medium in proportions of 1/2 leads to 23% lower viability during the pupa phase. The viability of chrysalides was within control framework and their individual fertility did not differ significantly. When the artificial nutrient medium contained 3/4 of polyethylene, the viability of chrysalides decreased significantly by 61%. Increasing the quantity of polyethylene in the artificial nutrient medium led to the extinguished viability which means polyethylene cannot be digested (processed). In this case, the experiment showed a delay in the development and the population reproduction was impossible. In addition to that, the individual fertility of females decreased 6 times if compared to the control group. The development phase under the conditions when the artificial nutrient medium contained ½ of polyethylene was 30 days longer than the development phase of the control group. The sex correlation in this research was 44 % of females and 56 % of males on average. As the results demonstrated the decrease of biological parameters of Galleria mellonella species when using polyethylene, we can assert that caterpillars do not digest polyethylene but in their digestive system, they have enzymes or bacteria that can influence the integrity of polyethylene.