Judul: Isolasi, dan karakterisasi bakteri selulolitik asal feses kuda (Equus caballus).
Abstrak: Penelitian ini bertujuan untuk mengisolasi dan karakterisasi bakteri selulolitik asal feses kuda yang diambil dari Equistrian center, Unit Rehabilitasi dan Reproduksi, Sekolah Kedokteran Hewan dan Biomedis Institut Pertanian Bogor (URR SKHB IPB). Penelitian dilakukan dalam tiga tahap. Tahap pertama adalah isolasi bakteri asal feses kuda dengan media N 98-5 dan media selektif selulolitik, tahap kedua dilakukan penapisan bakteri selulolitik dan tahap ketiga uji karaktererisasi isolat terpilih (uji gula-gula pereduksi, uji makroskopis, uji katalase, pewarnaan gram, dan uji aktivitas enzim selulase). Analisis aktivitas enzim menggunakan rancangan acak lengkap (RAL) pola faktorial dengan suhu, pH dan substrat yang berbeda. Suhu yang digunakan ialah 40o C, 50o C dan 60oC, pH yang digunakan ialah 5,6,7,8 serta substrat yang digunakan ialah CMC, Avicel dan Kertas Saring. Hasil penelitian ini di peroleh 3 isolat dengan nilai indeks selulolitik tertinggi yaitu isolat 1 (985.P.K.2.2), isolat 2 (985.P.K.2.3) dan isolat 3 (985.P.K.2.4). Hasil uji karakteriasi menunjukkan ketiga isolat memiliki morfologi yang berbeda. Isolat 2 dan 3, gram positif dan isolat 1, gram negatif. Hasil uji gula-gula pereduksi menunjukkan isolat 1 mampu mereduksi laktosa dan sukrosa, isolat 2 mampu mereduksi laktosa, dan isolat 3 mampu mereduksi sukrosa. Isolat 2 merupakan isolat dengan nilai indeks tertinggi dibandingkan isolat 1 dan 3 serta memiliki aktivitas enzim tertinggi. Hasil uji aktivitas enzim menunjukkan isolat 2 menghasilkan aktivitas terbaik dengan suhu optimum pada suhu 40o C dan pH optimum 5 dengan substrat kertas saring. Disimpulkan bahwa isolat 2, kandidat isolat terbaik dan hasil uji karakterisasi isolat 2 mengarah pada genus dari Bacillus., This study aimed to isolate and characterize cellulolytic bacteria from horse faeces taken from the Equistrian center, Rehabilitation and Reproduction Unit, School of Veterinary Medicine and Biomedical, Bogor Agricultural University (URR SKHB IPB). The research was conducted in three stages. The first stage was the isolation of bacteria from horse feces using N 98-5 media and selective cellulolytic media, the second stage was screening for cellulolytic bacteria and the third stage was the characterization test of the selected isolates (reducing sugar test, macroscopic test, catalase test, gram staining, and cellulase activity). The enzyme activity analysis used a factorial completely randomized design (CRD) with different temperatures, pH and substrates. The temperatures used were 40oC, 50oC and 60oC, the pH used was 5,6,7,8 and the substrates used were CMC, Avicel and filter paper. The results of this study obtained 3 isolates with the highest cellulolytic index value, namely isolate 1 (985.P.K.2.2), isolate 2 (985.P.K.2.3) and isolate 3 (985.P.K.2.4). The results of the characterization test showed that the three isolates had different morphology. Isolates 2 and 3, gram positive and isolate 1, gram negative. The results of the reducing sugar test showed that isolate 1 was able to reduce lactose and sucrose, isolate 2 was able to reduce lactose, and isolate 3 was able to reduce sucrose. Isolate 2 was the isolate with the highest index value compared to isolates 1 and 3 and had the highest enzyme activity. The results of the enzyme activity test showed that isolate 2 produced the best activity at an optimum temperature of 40oC and an optimum pH of
Keyword: bacillus, cellulolytic bacteria, enzyme activity, faeces hourse, fibrobacter