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Rice weevil (Sitophilus oryzae) and the lesser grain borer (Rhyzopertha dominica) are very important warehouse pests and, therefore, their control is crucial. At a key moment in the life of adult Sitophilus spp., the obligatory symbiotic nature of the Sodalis pierantonius bacterium opens up a new perspective for natural antibiotics and bactericides. In this study, we used nanopore sequencing for 16S rRNA barcoding to evaluate the internal bacteriome of S. oryzae and R. dominica and sterilized the insects’ internal microbiome with gentamicin. The treatment of the interior of S. oryzae with gentamicin (30 mg·g−1) hampered insect functioning (supposed lack of DOPA (4-dihydroxyphenylalanine) synthesis, stabilizing the exoskeleton by Sodalis pierantonius symbiont) and elicited a lethal effect in the first stages of this pest’s adult life. In addition, we identified biochemical biomarkers (enzymatic activity and substrate utilization) active in living individuals, but inactive in dead individuals (e.g., C8 esterase/lipase and α-chymotrypsin).

Pursuant to the principles of sustainable development, so as not to diminish the chances of living on our planet for future generations, special attention should be paid to certain aspects of our economy, including waste management. This paper presents an alternative way of recycling Styrofoam, by employing larvae of one of the common warehouse pests, the mealworm beetle (Tenebrio molitor L.). The aims of the research were to assess the biometric and enzymatic parameters of T. molitor larvae fed on Styrofoam, and to evaluate their possible use to decompose polystyrene waste. The experiment consisted of maintaining larvae for 10 weeks on nutrient substrates composed of foamed polystyrene (the control substrate was composed of oatmeal flakes). During the experiment, the mass of insects and the mass of ingested substrate were controlled. On the termination of the culture, digestive tracts of larvae from each replication was dissected to determine the enzymatic activity of the digestive system cells. To the biochemical analyses were made using the API® type assays. It has been demonstrated that owing to the enzymatic activity of the larval digestive tract and that of the gut microflora, mealworm larvae were able to digest waste slow to biodegrade, including polystyrene. A solution has been proposed, where providing suiTable conditions it will be possible to use mealworm larvae to utilise polystyrene waste.

The traditional demolition process for brickwork buildings results in a significant volume of mixed debris. The debris consists of ceramic bricks (and other wall elements), mortar, thermal insulation (usually expanded polystyrene or rockwool), smaller steel elements, pieces of wood, and glass. Such mixed debris is difficult to recycle. Separating thermal insulation that is “glued” by cement mortar to brickwork is probably the most difficult and time-consuming task in processing mixed debris. This task can be performed in a very different and fully “automatized” manner using Tenebrio molitor mealworms. The mealworms remove expanded polystyrene from brickwork surfaces and transform it into frass. In the paper, a research program aiming to prove the concept of using the mealworms of Tenebrio molitor for processing mixed debris is presented. The tests were conducted using two models of a three-layered brickwork wall, which is very common in Europe. The proposed approached was successful. Both types of used expanded polystyrene foam (EPS) were fully removed from multilayer wall specimens. The possibilities and limitations of the proposed processing method were discussed and analyzed. The conducted research proved that it is feasible to clean brickwork debris from the EPS using Tenebrio molitor mealworms. Differences in the speed of cleaning process regarding the type of EPS were noted. More research is needed to scale the process, and to find the best method for using frass. By using Tenebrio molitor mealworms, one can make the demolition process much cleaner.