RESUMO
<b>Background and Objective:</b> Diseases caused by microbes vectored by mosquitoes are still a health problem in tropical countries today. DHF and Malaria are the two primary diseases vectored by mosquitoes, the morbidity and mortality rates have increased in low countries until now. However, the best way to control these two diseases is to control vectors, namely mosquitoes. Research has been conducted to determine the bioactive content and larvicidal activity of local plant extracts of North Sulawesi. <b>Materials and Methods:</b> The clove and trumpet flower samples were obtained from Minahasa, while the nutmeg samples were obtained from Sitaro Regency. Empirically, people use plant parts to repel mosquitoes. Extraction of plant simplicia was carried out by the maceration method. Qualitative and quantitative methods carried out the phytochemical content analysis. Qualitative analysis uses Harborne's (1996) method while qualitative analysis uses the UV Vis Spectrophotometer method. Toxicity tests were carried out on mosquito larvae developed in the laboratory. <b>Results:</b> The results showed that combining clove leaf extract, nutmeg flesh extract and trumpet flower synergistically increased the bioactive content. Flavonoids increased in the combination of extracts compared to partial extracts. The combination of extracts showed the highest toxicity to mosquito larvae (LC<sub>50</sub>: 22.541 mg L<sup>1</sup>), while the lowest was the partial extract of clove leaves with LC<sub>50</sub> (54.965 mg L<sup>1</sup>). <b>Conclusion:</b> The combination of extracts showed the best toxicity activity on mosquito larvae. Research on bioactive characteristics and toxicity in adult mosquitoes needs to be carried out in the future.
