In recent years, a significant increase in mosquito-borne diseases has been recorded worldwide. Faced with the limitations of existing methods for controlling the vector mosquito population, the development of attractants to bait traps and repellents to limit host-vector contacts could be promising and environmentally-friendly control strategies. The purpose of this study was to evaluate the effect of hydroxycoumarins and their alkyls derivatives against Aedes albopictus, the main vector of several arboviruses. Synthesis, bioassays and field trials were carried out in Madagascar. The results showed that 3, 4 and 6-hydroxycoumarins are attractive to this mosquito, 4-hydroxycoumarin being the most effective both in the laboratory and under field conditions. In addition, a good synergistic effect was found with octenol to attract mosquitoes and especially Ae. albopictus in comparison to other mosquito species living in sympatry. On the contrary, the 4-s-butoxycoumarin and 4-s-pentoxycoumarin derivatives had a repellent effect with the former showing the most significant effect. Further optimization of the dose and structure of these products will be carried out in order to maximize their utility for the control of Ae. albopictus and other mosquitoes.

Mosquito-borne diseases like malaria are a major public health problem in tropical countries, such as Madagascar. Female Anopheles mosquito vectors the human malaria parasites (Plasmodium spp.) and is important indicator in malaria surveillance activities. Among the various means of vector control in Madagascar, the use of attractants for mass trapping of target species could be an alternative to insecticides. The aim of this study is to evaluate whether 4-hydroxycoumarin can be used as an attractant for anthropophilic Anopheles spp. vectors of malaria. For this, a field study was conducted using CDC light traps in the village of Ambohidray, Madagascar. 16 days of trapping was conducted and four replicates nights were performed for each product tested. 4-hydroxycoumarin, octenol and two types of blend of these products were tested. The results showed that 4-hydroxycoumarin (2 mg) have a significant attractive effect on Anopheles spp. and significant selectivity towards Anopheles gambiae s.l, and Anopheles mascarensis which are both significant malaria vectors in Madagascar. A synergy of 4-hydroxycoumarin with octenol was found to attract these mosquito vectors. A significant decrease in vector populations was observed during this experiment. These results suggest that 4-hydroxycoumarin could be useful for malaria surveillance and the control of vector populations. Mosquito-borne diseases present a major public health threat in tropical and subtropical areas and disproportionately impact developing nations, such as Madagascar 1. Among numerous mosquito vectors existent in Madagascar several Anopheles species are responsible for the transmission of malaria parasites 2-4. Due to their distribution, malaria is endemic to 90% of the country 5 and is the fourth leading cause of death in Madagascar 6. In order to limit the transmission of malaria, several methods of control have been implemented such as the use of long lasting insecticide-treated mosquito nets (LLINs) 7 , and indoor residual spraying (IRS) 8 to protect populations in regions with a high potential for epidemics 9. These control methods have shown significant efficacy, but they are also insufficient in the long term due to the rapid amplification of insecticide resistance in vector populations 10,11. In addition, controlling mosquito populations through the use of larvicides and adulticides has found to have negative impacts on ecosystems 12-14. For these reasons, the explorations of other more sustainable and environmentally friendly alternatives are encouraged worldwide 15,16. The use of attractants for selective and mass trapping has been suggested as a promising complementary to insecticide for malaria vector surveillance, control and reduction 17-19. A recent study has shown that 4-hydroxycoumarin, a compound derived from coumarin, a natural substance of plant origin, has a significant attractiveness activity on the mosquito Aedes albopictus, a mosquito vector of Dengue and Chikungunya, in

Cassava starch hydrolysis using poly(4‐vinylpyridine) hydrochloride gave 82% yield of edible glucose at 95 °C with only 2% of 5‐hydroxymethylfurfural as an easy to separate by‐product. Poly(4‐vinylpyridine) can be recovered and regenerated by water wash. The process doesn’t need prior treatment.