<![CDATA[AbstractThe red Rosella (Hibiscus sabdariffa L.) is medicinal plant that empirically has been used as an antituberculous drug. Rosella’s calix contains anthocyanins and other nutrients such as calcium, niacin, riboflavin and iron. This study was conducted experimentally starting with the making of Rosella flower extract by maceration method followed by examination of chemical content of extract. The antibacterial effect was performed by in-vitro method using 6 treatment groups, the negative control group, containing media and aquadest, the ethanol control group, containing media and 70% ethanol, the positive control group, containing media and isoniazid, and three groups of extracts each containing media and extracts with a concentration of 2.5 mg / mL , 5 mg / mL and 10 mg / mL. Mycobacterium tuberculosissuspension was shed over the entire surface and thenthe growth of Mycobacterium tuberculosis was observed after incubated for 21 days. The results showed that the ethanol extract of Rosella flower contain essential oils, fatty oil, tannins, reducing sugars, flavonoids, coumarins, triterpenoids, and anthocyanins. The 70% ethanol extract of calixs of Rosella flower (Hibiscus sabdariffa L.) at a concentration of 10mg/mLpossessinhibit the growth of Mycobacterium tuberculosis from the first week until the third week observation.                                                                                                                                 Keywords: antibacterial, 70% ethanol extract, rosella (hibiscus sabdariffa l.) AbstrakRosella merah (Hibiscus sabdariffa L.) merupakan salah satu tanaman obat yang secara empiris telah digunakan sebagai obat antituberkulosis.  Kaliks bunga Rosella mengandung antosianin serta berbagai zat gizi lain seperti kalsium, niasin, riboflavin dan zat besi.Penelitian ini bertujuan untuk mengetahui aktivitas ekstrak etanol 70% kaliks bunga rosella (Hibiscus sabdariffa L.) terhadap Mycobacterium tuberculosis strain H37Rv. Penelitian dilakukan secara eksperimental diawali dengan pembuatan ekstrak bunga Rosella secara maserasi dilanjutkan dengan penapisan kandungan kimia ekstrak. Efek antibakteri dilakukan secara in-vitro menggunakan 6 kelompok perlakuan, yaitu kelompok kontrol negatif, berisi media dan aquadest, kelompok kontrol pelarut, berisi media dan etanol 70%, kelompok kontrol positif, berisi media dan isoniazid, dan tiga kelompok ekstrak masing-masing berisi media dan ekstrak dengan konsentrasi 2,5 mg/mL, 5 mg/mL dan 10 mg/mL. Suspensi Mycobacterium tuberculosis dituangkan ke seluruh permukaan media diamati pertumbuhannya setelah diinkubasi selama 21 hari. Hasil penelitian menunjukkan ekstrak etanol kaliks bunga Rosella  mengandung minyak atsiri, minyak lemak, tannin, gula pereduksi, flavonoid, kumarin, triterpenoid, dan antosianin. Ekstrak etanol 70% kaliks bunga Rosella (Hibiscus sabdariffa L.) pada konsentrasi 10% memiliki efek antibakteri terhadap Mycobacterium tuberculosisdengan menghambat pertumbuhan Mycobacterium tuberculosis mulai dari mingu pertama sampai mnggu ketiga pengamatan. Kata kunci : antibakteri, ekstrak etanol 70%, rosella (hibiscus sabdariffa l.) ]]>
