Aedes aegypti is a major vector for Dengue, a deadly disease causing death of millions of people in developing countries both in urban and rural populations. Ae. aegypti control using chemical insecticide was always carried out and lead to a widespread insecticide resistance. Therefore, mosquito biological control is needed to replace the usage of chemical insecticide. A chitinolytic bacteria, was isolated from shrimp's waste (head and shell). The isolate showed chitinolytic activity as a

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... arent zone in colony inside the synthetic media, containing (w/v)-0,3 % colloidal chitin, 1% pepton, 0,5% yeast extract, 0,1% NaCl, 0,1% K2HPO4, 0,05% MgSO4.7H2O, 0,001% FeSO4.7H2O, 0,001% ZnSO4.7H2O, and each of 0,0001% CuSO4.5H2O, MnSO4.nH2O and CaCl2.2H2O at pH 7 and 30 0 C after 72 h of incubation. The isolate was identified as gram positive group based on gram staining. In the experimental method, four concentrations of chitinolytic bacteria (4%, 8%, 16% and 32%) was exposed to Ae. aegypti larvae. The result showed that chitinolytic bacterium degrades exoskeleton of third instar larvae of Ae. aegypti. Degradation of exoskeleton started on the 2 nd days and occurred in thorax region. Probit analysis showed LC50 value was obtaninedat concentration of 2%. Abstrak. Aedes aegypti merupakan vektor utama Dengue, penyakit yang menyebabkan kematian jutaan orang di negara-negara berkembang baik pada populasi perkotaan dan pedesaan. Pengendalian Ae. aegypti menggunakan insektisida kimia selalu dilakukan dan menyebabkan resistensi insektisida secara luas. Oleh karena itu, pengendalian nyamuk secara biologis diperlukan untuk menggantikan penggunaan insektisida kimia. Bakteri kitinolitik telah diisolasi dari limbah udang (kepala dan cangkang). Isolat menunjukkan aktivitas kitinolitik berupa zona bening di sekitar koloni dalam media sintetik yang mengandung (w/v)-0,3% koloidal kitin, 1% pepton, ekstrak ragi 0,5%, 0,1% NaCl, 0, 1% K2HPO4, 0,05% MgSO4.7H2O, 0001% FeSO4.7H2O, 0001% ZnSO4.7H2O, dan masing-masing 0,0001% CuSO4.5H2O, MnSO4.nH2O dan CaCl2.2H2O pada pH 7 dan suhu 30 0 C setelah 72 jam inkubasi. Isolat diidentifikasi sebagai kelompok positif gram berdasarkan pewarnaan gram. Dalam metode eksperimen, empat konsentrasi bakteri kitinolitik (4%, 8%, 16% dan 32%) dipaparkan pada larva Ae. aegypti. Hasil penelitian menunjukkan bahwa bakteri kitinolitik mendegradasi eksoskeleton larva instar ketiga Ae. aegypti. Degradasi eksoskeleton dimulai pada hari ke-2 dan terjadi di wilayah dada. Hasil analisa probit menunjukkan nilai LC50 pada konsentrasi 2%.