Chemical profiling of defence fluid produced by macrotermes carbonarius and globitermes sulphureus as potential natural insecticide

The usage of chemical insecticides has brought about negative implications such as adversely affecting the health in Malaysia. Nevertheless, new natural repellent and insecticide using plant as alternative have their own constrain such as growth time and require optimum environmental factors. Thus, new idea was brought in for the possible natural repellent and insecticide which was termite defense fluid. The idea of insect chemical communication was utilized in this study. The objective of this study is to evaluate the potential of Macrotermes carbonarius and Globitermes sulphureus defense fluid as a potential natural repellent and insecticide. In this work, the experiments were designed using the method of collection and identification of species, repellency, toxicity, and defense fluid compound profile in order to access the ability as potential natural insecticide. Termites were collected and identified according to width and length of termite soldier head. The termite defense fluid of both species was extracted and homogenized for 24 hours in methanol. Then, both of the extracts were tested on Macrotermes gilvus and Periplaneta americana L. In chemical profiling, Thin Layer Chromatography (TLC) was used as preliminary screening of compounds. Next, the defense fluid was injected into GC-MS (Gas Chromatography-Mass Spectrometry) for further identification of compound. G. sulphureus extract showed the highest repellent efficiency effect for seven days for M. gilvus and thirty days for P. americana L. at 20 mg/ml. Meanwhile, toxicity of G. sulphureus extract had low LC50 (16.97 mg/ml) compared to M. carbonarius extract (18.875 mg/ml) on M. gilvus. M. carbonarius extract that consisted of six insecticidal and two repellent compounds. Meanwhile, G. sulphureus extract had five insecticidal and three repellent compounds. The similarity and differences compound gave different effects and trends in repellency and toxicity. Hence, G. sulphureus defense fluid was concluded as the potential natural repellent and insecticide compared to M. carbonarius extract. Further investigations of these compounds activities are needed. The identification of both defense fluid as repellent and insecticide on M. gilvus can play a new role for alternatives in finding new sustainable resources of natural repellent and insecticide especially termiticide.