Effect of natural products on gut microbes in Formosan subterranean termite, Coptotermes formosanus

The ability of three natural products (neem extract, capsaicin, and gleditschia) to reduce the number of Formosan subterranean termite (FST) hindgut microbes was investigated. FSTs were placed in Petri dishes containing a food source soaked in one of these extracts/compounds. The numbers of three flagellated protozoan species that inhabit the FST hindgut (Pseudotrichonympha grassii, Spirotrichonympha leidyi and Holomastigotoides hartmanni) and spirochaetes were counted over a defined period and analysed for changes in abundance. The results indicated that the neem extract was capable of reducing the population of P. grassii and spirochaetes. Exposure to this extract resulted in significant FST mortality. However, gleditschia extract and capsaicin did not reduce the FST gut microbial population at the concentrations used in this study.