Skripsi

Pengaruh Senyawa Camphor (C10H16O) terhadap Aktivitas Enzim Detoksifikasi dan Histopatologi Midgut Larva Culex quinquefasciatus (Diptera: Culicidae) di Jakarta Timur = Effect of Camphor Compounds (C10H16O) on Detoxification Enzyme Activity and Histopathology Culex quinquefasciatus (Diptera: Culicidae) in East Jakarta.

Latar belakang: Filariasis yang disebarkan oleh nyamuk Culex quinquefasciatus masih menjadi masalah kesehatan masyarakat di Indonesia. Pemberantasan filariasis dengan menggunakan insektisida sintetis menyebabkan resistensi Cx. quinquefasciatus terhadap insektisida tersebut. Tujuan penelitian ini untuk menganalisis toksisitas senyawa camphor terhadap larva Cx. quinquefasciatus dan mekanismenya yang terfokus pada enzim detoksifikasi dan kelainan histopatologi midgut. Metode: Larva Cx. quinquefasciatus diperoleh dari lapangan yaitu habitat alami di Jakarta Timur. Bioassay larva mengikuti protokol WHO. Larva tersebut dipaparkan dengan konsentrasi camphor yaitu 0,5, 1,5, 10,5, 25,5, dan 50 ppm selama 24, 48, dan 72 jam dan pengulangan dilakukan sebanyak 5 kali. Kelainan histopatologi midgut diperiksa dengan metode rutin histopatologi dengan pewarnaan hematoksilin dan eosin (HE). Enzim detoksifikasi meliputi asetilkolinesterase (AChE), glutathione S transferase (GST), dan oksidase diperiksa dengan metode CDC (Centers for Disease Control and Prevention). Hasil: Terdapat perbedaan bermakna angka mortalitas larva Cx. quinquefasciatus di setiap konsentrasi camphor (p < 0.05). Camphor dengan konsentrasi 50 ppm mengakibatkan 100% mortalitas pada larva Cx. quinquefasciatus selama 48 jam. Nilai LC50 sebesar 2,32 ppm dan LC90 sebesar 12,40 ppm. Kelainan histopatologi yang masif di seluruh midgut meliputi food bolus dan membrane peritrofik mengalami keretakan, lapisan epitelia terpecah-pecah, dan bentuk sel epitel serta mikrovili menjadi tidak teratur. Aktivitas AChE dan GST meningkat bermakna (p < 0.05), sedangkan oksidase menurun (p < 0.05). Kesimpulan: Camphor memperlihatkan aktivitas larvisida yang tinggi terhadap larva Cx.quinquefasciatus dengan mekanisme kerusakan histopatologi yang masif pada bagian midgut dan menghambat aktivitas AChE dan oksidase.
Kata kunci: Cx. quinquefasciatus, camphor, histopatologi midgut, enzim detoksifikasi.



Introduction: Filariasis transmitted by Culex quinquefasciatus mosquitoes is still a public health problem in Indonesia. Eradication of filariasis by using synthetic insecticides causes resistance to Cx. quinquefasciatus. Cx. quinquefasciatus against these insecticides. The purpose of this study was to analyze the toxicity of camphor compounds to larvae ofCx. Cx. quinquefasciatus and its mechanisms focused on detoxifying enzymes and midgut histopathological abnormalities. Method: Larvae of Cx. quinquefasciatus was obtained from the field, which is a natural habitat in East Jakarta. Larval bioassays followed the WHO protocol. The larvae were exposed to camphor concentrations of 0.5, 1.5, 10.5, 25.5, 50 ppm for 24, 48, and 72 hours and repeated 5 times. Midgut histopathological abnormalities were examined by routine histopathological methods with hematoxylin and eosin (HE) staining. Detoxification enzymes including acetylcholinesterase (AChE), glutathione S transferase (GST), and oxidase were examined using the CDC (Centers for Disease Control and Prevention) method. Result: There was a significant difference in the mortality rate of larvae Cx. quinquefasciatus in each camphor concentration (p < 0.05). Camphor with a concentration of 50 ppm resulted in 100% mortality in larvae Cx. quinquefasciatus for 48 hours. The LC50 value is 2.32 ppm and the LC90 is 12.40 ppm. Massive histopathological abnormalities throughout the midgut include the food bolus and the peritrophic membrane are fractured, the epithelial layer is fragmented, and the shape of the epithelial cells and microvilli becomes irregular. AChE and GST activities increased significantly (p < 0.05), while oxidase activity decreased (p < 0.05). Conclusion: Camphor showed high larvicidal activity against Cx. quinquefasciatus larvae with massive histopathological damage mechanism in the midgut and inhibited oxidase activity.
Keywords: Cx. quinquefasciatus, camphor, midgut histopathology, detoxification enzymes.