Electronic Theses and Dissertation

Tantia utari. (2026). eksplorasi, isolasi, dan identifikasi bakteri dari dinding gua ek leuntie aceh besar terhadap potensi pembentukan senyawa organik dan anorganik. [skripsi. universitas syiah kuala]. dibawah bimbingan dr. rahmad rizki fazli, s.pd., m.si. dan drs. zulfadli, m.si. gua ek leuntie merupakan habitat kelelawar yang kaya akan mikroorganisme, termasuk bakteri yang berpotensi dimanfaatkan dalam bidang bioteknologi dan rekayasa lingkungan. penelitian ini bertujuan untuk mengeksplorasi, mengisolasi, dan mengidentifikasi bakteri dari dinding gua ek leuntie, aceh besar, serta mengevaluasi kemampuan isolat bakteri dalam menghasilkan biosurfaktan dan menginduksi presipitasi kalsium karbonat (caco₃) melalui mekanisme microbial induced calcium carbonate precipitation (micp). penelitian menggunakan metode deskriptif kualitatif dan kuantitatif dengan teknik quota sampling. isolat dikarakterisasi berdasarkan morfologi koloni, pewarnaan gram, uji urease, oil spreading test, uji presipitasi caco₃, dan kurva pertumbuhan. hasil penelitian menunjukkan bahwa isolat yang diperoleh diduga termasuk ke dalam genus staphylococcus, pseudomonas aeruginosa, bacillus mycoides, dan acinetobacter. sebagian besar isolat menunjukkan aktivitas urease yang mengindikasikan potensi sebagai bakteri penginduksi micp. isolat batu berlumut menghasilkan presipitat caco₃ tertinggi sebesar 0,899 g, sedangkan aktivitas biosurfaktan tertinggi ditunjukkan oleh genus staphylococcus dengan diameter zona bening 5,5 cm. kurva pertumbuhan menunjukkan fase lag, eksponensial, stasioner, dan kematian secara berurutan. berdasarkan hasil penelitian, bakteri yang diisolasi dari dinding gua ek leuntie berpotensi sebagai agen biomineralisasi melalui mekanisme micp dan penghasil biosurfaktan sehingga berpotensi dikembangkan untuk aplikasi bioteknologi dan rekayasa lingkungan. kata kunci: bakteri gua, gua ek leuntie, isolasi bakteri, identifikasi bakteri, microbial induced calcium carbonate precipitation (micp), biosurfaktan, urease

Tantia Utari. (2026). Exploration, Isolation, and Identification of Bacteria from the Walls of Ek Leuntie Cave, Aceh Besar, Regarding Their Potential for Organic and Inorganic Compound Formation. [Thesis. Syiah Kuala University]. Under the supervision of Dr. Rahmad Rizki Fazli, S.Pd., M.Si. and Drs. Zulfadli, M.Si. Ek Leuntie Cave is a bat-inhabited cave rich in microorganisms, including bacteria with potential applications in biotechnology and environmental engineering. This study aimed to explore, isolate, and identify bacteria from the walls of Ek Leuntie Cave, Aceh Besar, and to evaluate their ability to produce biosurfactants and induce calcium carbonate (CaCO₃) precipitation through the Microbial Induced Calcium Carbonate Precipitation (MICP) mechanism. This research employed descriptive qualitative and quantitative methods using a quota sampling technique. The bacterial isolates were characterized based on colony morphology, Gram staining, urease activity, oil spreading test, CaCO₃ precipitation test, and bacterial growth curve analysis. The results showed that the isolates exhibited diverse morphological characteristics and were presumed to belong to the genera Staphylococcus, Pseudomonas aeruginosa, Bacillus mycoides, and Acinetobacter. Most isolates demonstrated urease activity, indicating their potential as MICP-inducing bacteria. The moss-covered rock isolate produced the highest CaCO₃ precipitate (0.899 g), while the highest biosurfactant activity was observed in the Staphylococcus isolate, with a clear zone diameter of 5.5 cm. The bacterial growth curve consisted of a lag phase, an exponential phase, a stationary phase, and a death phase. In conclusion, bacteria isolated from the walls of Ek Leuntie Cave have the potential to serve as biomineralization agents through the MICP mechanism and as biosurfactant producers, highlighting their promising applications in biotechnology and environmental engineering Keywords: cave bacteria; Ek Leuntie Cave; bacterial isolation; bacterial identification; Microbial Induced Calcium Carbonate Precipitation (MICP); biosurfactants; urease