The relative antibacterial activities of excretion/secretion (ES) from two carrion-feeding insects, Calliphora vicina Robineau-Desvoidy and Dermestes maculatus DeGeer, and a detritivore, Tenebrio molitor Linnaeus, were compared to that of Lucilia sericata Meigen, a species with ES of known antibacterial capacity, in order to explore the antimicrobial potential of other carrion and detritivore species. Viable counts were used to assess time-kill of ES against five bacterial species, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Pseudomonas aeruginosa and Proteus mirabilis. Antibacterial activity was recorded in all four insect species although T. molitor and D. maculatus were the most effective in controlling growth of P. mirabilis. The blowflies were more effective in controlling a wider range of both Gram-positive and Gram-negative bacteria. The larval ES from all species was shown to reduce bacterial growth rate although differences in antibacterial spectrum were noted and the degree of potency varied between the four species. These differences may be explained ecologically by the different colonisation times of each insect species on the corpse. Overall, this study demonstrates that research into other carrion-feeding insect species has potential to provide an increased source of antimicrobial chemicals to broaden the range of bacterial species beyond that currently controlled using L. sericata.

Secretions were induced from second (invasive) stage juveniles (J2s) of the potato cyst nematode Globodera rostochiensis by exposing them to 5-methoxy-N,N-dimethyl tryptamine oxalate (DMT). Secretions were collected from J2s in sufficient quantity to allow direct analysis. Gel electrophoresis followed by monochromatic silver staining demonstrated the presence of at least 10 proteins. The presence of several enzymes, including superoxide dismutase and proteases, was demonstrated using Western blots and activity assays. Antisera raised against the secretions recognized bands on Western blots consistent in molecular mass with those identified on silver stained gels. The antisera recognized structures implicated in the production of secretions including the subventral gland cells and surface of J2s.

Electrophoresis of secretions collected from Globodera pallida revealed a smeared region between 25 and 50 kDa, and a single band of <20 kDa. The secretions were used to raise an antiserum (LW1). Immunoblotting of parasite homogenates with LW1 differentiated G. pallida from its sibling species G. rostochiensis and revealed differences between different populations of G. pallida and G. rostochiensis. Indirect immunofluorescence studies with LW1 indicated that at least some of the secretions were surface localized and that antibody binding to the nematode surface was periodate sensitive. Periodate sensitivity indicated that these differences could be due to glycosylation differences. Glycosylation differences were also detected by blotting nematode homogenates with the lectin wheat germ agglutinin (WGA). WGA was also able to differentiate between G. rostochiensis which gave 2 bands at 130 kDa and 110 kDa, and G. pallida which produced 2 bands present at 120 kDa and 110 kDa. Further localization studies using immunoelectron microscopy demonstrated that antibody binding could be seen to secretions found in the pump chamber of the metacorpal bulb at the base of the stylet. From further specimens it could be observed that the contents of the subventral glands were heavily labelled, indicating that the material seen in the metacorpal bulb had originated from the subventral glands.