Evaluation of the chemical defense fluids of Macrotermes carbonarius and Globitermes sulphureus as possible household repellents and insecticides

Abstract

The use of chemical insecticides has had many adverse effects. This study reports a novel perspective on the application of insect-based compounds to repel and eradicate other insects in a controlled environment. In this work, defense fluid was shown to be a repellent and insecticide against termites and cockroaches and was analyzed using gas chromatography-mass spectrometry (GC-MS). Globitermes sulphureus extract at 20 mg/ml showed the highest repellency for seven days against Macrotermes gilvus and for thirty days against Periplaneta americana. In terms of toxicity, G. sulphureus extract had a low LC₅₀ compared to M. carbonarius extract against M. gilvus. Gas chromatography-mass spectrometry analysis of the M. carbonarius extract indicated the presence of six insecticidal and two repellent compounds in the extract, whereas the G. sulphureus extract contained five insecticidal and three repellent compounds. The most obvious finding was that G. sulphureus defense fluid had higher potential as a natural repellent and termiticide than the M. carbonarius extract. Both defense fluids can play a role as alternatives in the search for new, sustainable, natural repellents and termiticides. Our results demonstrate the potential use of termite defense fluid for pest management, providing repellent and insecticidal activities comparable to those of other green repellent and termiticidal commercial products.

Figure 1

Thin layer chromatography (TLC) result of the M. carbonarius defense fluid extract shows four different compounds in plate a and the standard band (red circle) in plate b.

Figure 2

Thin layer chromatography (TLC) results of G. sulphureus defense fluid extract in plate a and standard band in plate b under 254 nm UV light in a UV Viewing Chamber (UVITEC, England, United Kingdom). The red circle indicates a band obtained on both plates.