Electronic Theses and Dissertation

ABSTRAK
Siput air tawar (Faunus ater) merupakan gastropoda yang banyak ditemukan di perairan
seperti muara, danau, dan sungai. Cangkangnya berwarna hitam dengan bentuk memanjang dan
sering digunakan sebagai bahan tambahan dalam masakan sayuran. Siput ini memperoleh
makanannya dengan cara menyaring substrat organik dari lingkungan sekitarnya, yang dapat
menyebabkan adanya keberadaan bakteri termasuk Enterobacter, dalam daging siput tersebut.
Penelitian ini bertujuan untuk mendeteksi dan mengidentifikasi keberadaan bakteri Bacillus cereus
pada siput air tawar (Faunus ater) yang hidup di sungai Leupung, Saney dan Gle Bruek, Aceh Besar
menggunakan analisis gen 16S rRNA. Penelitian ini dilakukan dengan mengisolasi bakteri
menggunakan media Brain Heart Infusion Broth (BHIB), Mannitol Salt Agar (MSA) dan
pewarnaaan Gram serta dilakukan uji molekuler menggunakan analisis gen 16S rRNA. Hasil
penelitian menunjukkan adanya kekeruhan pada media BHIB, terdapat koloni bewarna kekuningan
yang berbentuk bundar pada media MSA, pada pewarnaan Gram menunjukkan warna ungu sebagai
Gram positif dan berbentuk basil. Hasil analisis molekuler berupa parsial gen 16S rRNA
menunjukkan bahwa isolat memiliki kemiripan 100,00% dan nilai Quary Coverage 100% dengan
bakteri Bacillus cereus strain ARCHA-01. Secara konstruksi pohon filogenetik pada isolat
menunjukkan kedekatan dan kekerabatan dengan Bacillus cereus strain ARCHA-01, yang
ditunjukkan oleh posisi yang berdekatan pada pohon filogenetik. Kesimpulan pada penelitian ini
siput air tawar (Faunus ater) dari Sungai Leupung, Saney, dan Gle Bruek, Aceh Besar terdeteksi
mengandung bakteri Bacillus cereus berdasarkan identifikasi secara analisis molekuler gen 16S
rRNA.

ABSTRACT Freshwater snails (Faunus ater) are gastropods that are commonly found in waters such as estuaries, lakes, and rivers. Their shells are black with an elongated shape and are often used as additional ingredients in vegetable dishes. These snails obtain their food by filtering organic substrates from their surrounding environment, which can cause the presence of bacteria including Enterobacter, in the snail meat. This study aims to detect and identify the presence of Bacillus cereus bacteria in freshwater snails (Faunus ater) that live in the Leupung, Saney and Gle Bruek rivers, Aceh Besar using 16S rRNA gene analysis. This study was conducted by isolating bacteria using Brain Heart Infusion Broth (BHIB), Mannitol Salt Agar (MSA) media and Gram staining and molecular testing using 16S rRNA gene analysis. The results showed turbidity in the BHIB media, there were yellowish colonies that were round in shape on the MSA media, and Gram staining showed purple as Gram positive and bacillus-shaped. The results of the molecular analysis in the form of partial 16S rRNA gene showed that the isolate had 100.00% similarity and 100% Quary Coverage value with Bacillus cereus strain ARCHA-01 bacteria. In terms of phylogenetic tree construction, the isolate showed closeness and kinship with Bacillus cereus strain ARCHA-01, which was indicated by the adjacent position in the phylogenetic tree. The conclusion of this study was that freshwater snails (Faunus ater) from the Leupung, Saney, and Gle Bruek Rivers, Aceh Besar were detected to contain Bacillus cereus bacteria based on identification by molecular analysis of the 16S rRNA gene.