<![CDATA[ABSTRAK Tapak dara (Catharanthus roseus) merupakan tanaman yang berpotensi sebagai obat tradisional.Tanaman ini tumbuh liar maupun dibudidayakan sebagai tanaman hias. Tanaman tapak dara mengandung senyawa metabolit sekunder seperti alkaloid, saponin, tanin, triterpenoid, dan flavonoid yang berfungsi sebagai antimikroba, dan antivirus. Penelitian ini bertujuan untuk mengetahui diameter zona hambat dari ekstrak etanol daun Tapak dara (Catharanthus roseus) terhadap pertumbuhan bakteri Escherichia coli dengan konsentrasi ekstrak 60%, 70%, 80%, 90%. Metode yag digunakan yaitu eksperimental secara difusi disk. Hasil penelitian yang didapatkan terhadap Pertumbuhan Bakteri Escherichia coli pada konsentarsi berturut-turut yaitu 60%, 70%, 80%,90% diperoleh zona hambat rata-rata 13,3 mm, 18,6 mm, 20,6 mm, dan 22,6. Berdasarkan hasil, maka dapat disimpulkan bahwa ekstark etanol daun tapak dara mampu menghambat pertumbuhan bakteri Escherichia coli yang ditandai dengan adanya zona bening di sekitar Paper disk. Kata Kunci :Daun tapak dara, difusi disk, daya hambat, Escherichia coli, ABSTRACT Tapak dara (Catharanthus roseus) is a plant that has the potential as a traditional medicine. This plant grows wild or is cultivated as an ornamental plant. Tapak dara plants contain secondary metabolite compounds such as alkaloids, saponins, tannins, triterpenoids, and flavonoids that function as antimicrobials and antiviruses. This study aims to determine the diameter of the inhibition zone of ethanol extract of Tapak dara leaves (Catharanthus roseus) on the growth of Escherichia coli bacteria with extract concentrations of 60%, 70%, 80%, 90%. The method used is experimental by disk diffusion. The results of the study obtained on the Growth of Escherichia coli Bacteria at consecutive concentrations of 60%, 70%, 80%, 90% obtained an average inhibition zone of 13.3 mm, 18.6 mm, 20.6 mm, and 22.6. Based on the results, it can be concluded that the ethanol extract of tapak dara leaves is able to inhibit the growth of Escherichia coli bacteria which is indicated by the presence of a clear zone around the Paper disk. Keywords: Tapak dara leaves, disk diffusion, inhibition, Escherichia coli]]>
