Skripsi

Efek Curcumin dan Hexahydrothimol terhadap Nyamuk Betina Culex quinquefasciatus: Kajian terhadap Mortalitas, Aktivitas Enzim Detoksifikasi, dan Perilaku Menghisap Darah = The effects of Curcumin and Hexahydrothymol to Adult Female Mosquito Culex quinquefasciatus: A study on Mortality, Detoxification Enzyme Activity, and Blood Feeding Activity.

Latar belakang: Di Indonesia, filariasis merupakan masalah kesehatan masyarakat. Vektor utama dari filariasis limfatika adalah nyamuk Culex quinquefasciatus. Pengendalian vektor nyamuk menggunakan insektisida sintetis dapat menimbulkan resistensi nyamuk betina Cx. quinquefasciatus terhadap insektisida tersebut. Oleh karena itu, diperlukan insektisida alternatif dari bahan alami (curcumin (C21H20O6) dan hexahydrothymol (C10H20O)). Penelitian ini difokuskan pada aktivitas curcumin dan hexahydrothimol dalam membunuh nyamuk betina Cx. quinquefasciatus, mekanismenya yang meliputi perubahan aktivitas enzim detoksifikasi, dan pengaruhnya terhadap perilaku nyamuk betina dalam mengisap darah. Metode: Bioassay nyamuk betina Cx. quinquefasciatus mengikuti protokol WHO. Nyamuk tersebut dipaparkan dengan kertas filter yang sudah mengandung curcumin dan hexahydrothymol dengan konsentrasi masing-masing 10, 25, 50 ppm. Bioassay dilakukan dengan ulangan 3 kali. Pemeriksaan enzim asetilkolinesterease (AChE), glutation s-transferase (GST), dan oksidase dengan menggunakan metode biokimia yaitu homogenisasi yang diikuti dengan pembacaan menggunakan ELISA reader. Pengujian perilaku makan darah dan engorgement time menggunakan modifikasi dari metode Xue et al. Hasil: Curcumin dan hexahydrothymol dengan konsentrasi 50 ppm menyebabkan angka mortalitas 100% pada nyamuk betina Cx. quinquefasciatus. Curcumin memperlihatkan nilai LC50 = 0,455 ppm dan LC90 =1,360 ppm serta hexahydrothymol sebesar LC50¬ = 0,455 ppm dan LC90 =1,360 ppm. Aktivitas AChE dan GST meningkat (p < 0,05), sedangkan oksidase mengalami inhibisi (p < 0,05). Hexahydrothymol mengakibatkan perubahan perilaku waktu kenyang yang lebih singkat dan persentase makan darah yang lebih kecil dibandingkan dengan curcumin. Kesimpulan: Hexahydrothymol dan curcumin dengan konsentrasi 50 ppm mempunyai potensi sebagai insektisida alternatif untuk pengendalian populasi nyamuk Cx. quinquefasciatus
Kata kunci: Culex quinquefasciatus, curcumin, hexahydrothimol, enzim detoksifikasi, perilaku makan darah, engorgement time



Introduction: : In Indonesia, filariasis is a community health problem. The main vector of lymphatic filariasis is the mosquito Culex quinquefasciatus. Mosquito vector control using synthetic insecticide shows side effect such as female Cx. quinquefasciatus resistancy towards synthetic insecticide. Therefore, an alternative insecticide from a natural substance is needed (curcumin (C21H20O6) and hexahydrothymol (C10H20O)). This research is focused on the activity of curcumin and hexahydrothymol in the mortality of female Cx. quinquefasciatus, its mechanism which includes changes in detoxification enzyme activity, and its effect on the blood feeding behaviour of the female mosquito. Method: Bioassay of female Cx. quinquefasciatus were conducted according to the WHO protocol. The adult mosquitoes were exposed to filter paper containing curcumin and hexahydrothymol each with the concentration of 10, 25, 50 ppm. The bioassay was done with 3 replication. Biochemistry method was used to evaluate acetycholinesterase (AChE), glutathione S-transferase (GST), and oxidase enzyme activity (homogenization followed by analysis from ELISA reader). Blood feeding behaviour and engorgement time of the mosquitoes were examine according to the method used by Xue et al, with modification. Result: Curcumin and hexahydrothymol at 50 ppm concentration caused 100% mortality in females of Cx. quinquefasciatus. Curcumin show LC50 value of 0,455 ppm and LC90 value of 1,360 ppm. Hexahydrothymol show LC50 value of 0,455 ppm and LC90 value of 1,360 ppm. AChE and GST activities increased (p < 0.05), while oxidase was inhibited (p < 0.05). Hexahydrothymol resulted in a shorter engorgement time and a smaller percentage of blood feeding behaviour compared to curcumin. Conclusion: Curcumin and hexahydrothymol at 50 ppm concentration exhibit a potential to be an alternative insecticide for the control of Cx. quinquefascaiatus population.
Keywords: Culex quinquefasciatus, curcumin, hexahydrothymol, detoxification enzyme, blood feeding behaviour, engorgement time