Iranian Journal of Fisheries Sciences
مجله علوم شیلاتی ایران
IJFS
Agriculture
http://jifro.ir
1
admin
1562-2916
10.18869/acadpub.ijfs
en
jalali
1399
8
1
gregorian
2020
11
1
19
6
online
1
fulltext
en
Research Article: Isolation, biochemical and molecular detection of Bacillus subtilis and Bacillus licheniformis from the digestive system of rainbow trout (Oncorhynchus mykiss) and its inhibitory effect on Aeromonas hydrophila
aquaculture
aquaculture
پژوهشي
Orginal research papers
Our study was focused on characterization of dominant Bacillus bacteria isolated from the digestive tract of <em>Oncorhynchus mykiss</em>. After 8 weeks, the fish fed with probiotic-free diet were dissected under strictly controlled conditions. Fish intestines were eviscerated and its content diluted to 10<sup>−4</sup> using Ringer solution. Two isolated bacteria were Gram-positive, catalase-positive, and oxidase-negative, based on the biochemical tests. A mixed of the two strains was the most efficient isolates determined in <em>O. mykiss. </em>Molecular characterization using PCR-Ribotyping was carried out using sequencing the 16S rRNA gene of both strains, which isolated two bacteria, <em>Bacillus subtilis</em> Ahari.H1 and <em>B. licheniformis</em> Ahari. H2<em>.</em> The isolated bacteria could tolerate 0.3% bile salt and non-hemolytic in nature. They also showed resistance to pH at 2.5 and 4 for acid test and 2.3 and 7 for gastric juice, pepsin and trypsin. It is concluded that the efficiency of the isolated probiotics can be candidates as probiotic in fish culture. It was unveiled that these strains can successfully diminish <em>Aeromonas hydrophila</em> pathogenicity in rainbow trout.<br>
Rainbow trout, Probiotic, Bacillus subtilis Ahari.H1, Bacillus licheniformis Ahari.H2, PCR
2824
2845
http://jifro.ir/browse.php?a_code=A-10-3473-1&slc_lang=en&sid=1
S.M.A.
Ebne al-Torab
100319475328460038289
100319475328460038289
No
Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, Tehran, Iran
H.
Ahari
Assoc.Prof.
100319475328460038290
100319475328460038290
Yes
Agricultural Sciences and Food Technology, Science and Research Branch, Islamic Azad University, Tehran, Iran
S.
Kakoolaki
bsh443@gmail.com
100319475328460038291
100319475328460038291
No
Iranian Fisheries Sciences Research Institute, Agricultural Research, Education and Extension Organization, Tehran, Iran