Electronic Theses and Dissertation

Bakteri endofit merupakan bakteri yang terdapat dan hidup pada tanaman inangnya tanpa merusak atau memberi efek negatif. daun jeruk purut merupakan tanaman yang dapat menghasilkan senyawa metabolit sekunder berupa saponin, tannin, flavonoid, alkaloid dan terpenoid yang memiliki potensi sebagai antibakteri. penelitian ini bertujuan untuk mengetahui jumlah isolat yang tumbuh, karakteristik, adanya aktivitas antibakteri serta kandungan metabolit sekunder yang dihasilkan. hasil penelitian didapatkan delapan isolat bakteri endofit yang berhasil diisolasi dari daun jeruk purut (citrus hystrix). berdasarkan hasil karakteristik morfologi, pewarnaan gram dan pengujian biokimia menunjukkan bahwa isolat bedj1 dan bedj3 diduga berasal dari genus neisseria, bedj2 dan bedj6 diduga berasal dari genus nitrosococcus, bedj4 diduga berasal dari genus klebsiella dan bedj5 dan bedj8 diduga berasal dari genus pseudomonas dan bedj7 diduga berasal dari genus enterobacter. terdapat tiga isolat yang hanya mampu menghambat pertumbuhan bakteri staphylococcus aureus yaitu bedj1, bedj3 dan bedj8. bakteri endofit daun jeruk purut mengandung senyawa terpenoid dan asam lemak yang berperan sebagai antibakteri. kata kunci : bakteri endofit, daun jeruk purut, citrus hystrix, antibakteri, staphylococcus aureus, terpenoid.

Endophytic bacteria are bacteria that exist and live on their host plants without damaging or having negative effects. Kaffir lime leaves are plants can produce secondary metabolites in the form of saponins, tannins, flavonoids, alkaloids and terpenoids which have potential as antibacterials. This research aims to determine the number of isolates that grow, their characteristics, their antibacterial activity and the content of secondary metabolites produced. The results of the study obtained eight endophytic bacterial isolates that were successfully isolated from kaffir lime leaves (Citrus hystrix). Based on the results of morphological characteristics, Gram staining and biochemical testing showed that isolates BEDJ1 and BEDJ3 were thought to be genus Neisseria, BEDJ2 and BEDJ6 were thought to be genus Nitrosococcus, BEDJ4 were thought to be genus Klebsiella, BEDJ5 and BEDJ8 were thought to be genus Pseudomonas and BEDJ7 were thought to be genus Enterobacter. There were three isolates only able to inhibit the growth of Staphylococcus aureus bacteria, namely BEDJ1, BEDJ3 and BEDJ8. Endophytic bacteria in kaffir lime leaves contain terpenoid compounds and fatty acids which act as antibacterials. Keywords : Endophytic bacteria, Kaffir lime leaves, Citrus hystrix, antibacterial, Staphylococcus aureus, terpenoids.