Infectious disease cause by antibiotic resistant bacteria has been more difficult to treat because the ability of these bacteria to avoid the effect of antibiotic medication. Nowadays, water environment especially river has become the reservoir for the dissemination of antibiotic resistant bacteria due to antibiotic contamination derived from human activities. The exposure to antibiotic resistance bacteria in water increase the health risks associated with the waterborne bacteria in animals and humans. Therefore, this study was carried out to investigate the presence of antibiotic resistant bacteria from two rivers; Ibai River and Terengganu River in Terengganu. A total of 24 bacterial strains were isolated from both rivers. Antibiotic susceptibility of the bacteria isolates was assayed according to the Kirby-Bauer disk diffusion method using six types of antibiotics such as ampicillin, rifampicin, gentamicin, tetracycline, ciprofloxacin and chloramphenicol. The results of this study indicate that 100% of bacterial strains were resistant to at least two antibiotics tested. The multiple antibiotic resistant (MAR) index of these bacteria was calculated and 23 bacterial strains show MAR index of more than 20%. Among the 23 isolates, a total of 10 bacterial strains (2A, 2B, 2C, 2I, 3A, 3B, 4A, 4C, 4D and 4E) were successfully identified as Chromobacterium violaceum, Enterobacter tabaci, Bacillus wiedmannii, Acinetobacter baumannii, Klebsiella quasipneumoniae subsp. quasipneumoniae, Chromobacterium aquaticum, Cupriavidus metallidurans, Weeksella massiliensis, Cupriavidus necator and Acinetobacter nosocomialis. The results from this study show that both of the rivers are exposed to high level of antibiotics compound which may lead the bacteria to develop mechanism of antibiotic resistant. This may cause a serious threat to the public health and environment.

Antibiotic resistant bacteria have been a major concern due to the problems that they may pose in terms of public and environmental health. This present study aimed to investigate the presence of antibiotic resistance among bacterial strains isolated from rivers and to determine the impact of various human activities on the distribution of antibiotic resistant bacteria. Bacteria were isolated from river water samples of Lebir River (Point 1 and Point 2) and Kelantan River (Point 3 and Point 4). A total of 27 bacterial isolates were successfully isolated from the rivers, followed by characterization and identification of the isolates using a series of biochemical tests. All the isolated bacteria were predicted as Actinomyces sp., Arachnia sp.,

The intensive use of antibiotics in aquaculture results in the proliferation of antibiotic. In this study, antibiotic resistant bacteria from six different aquaculture sources (pond of Fisheries Research Institute (FRI), and rivers of Kukup, Pulai, Pendas Laut, Sungai Melayu and Kong Kong) were isolated. These isolates were tested for antibiotic resistance against seven antibiotics via the disc diffusion method. Finally, phenotypic and genotypic identification via 16S rRNA sequencing and phylogenetic analysis were carried out. The results show that 58 out of 118 bacterial isolates are resistant to multiple antibiotics. The highest isolate resistance was observed towards rifampicin (89.66%), followed by ampicillin (79.31%) and sulfafurazole (67.24%). The isolates with multiple antibiotic resistant (MAR) index values with more than 20% were subjected to 16S rRNA gene sequencing. The majority of the bacterial strains exhibit multiple antibiotic resistance, indicating that they were isolated from highly contaminated sources based on the tested water qualities profiles, which showed the high level of turbidity and total dissolved solid (TDS) in most sampling sites with the high number of MAR bacteria obtained.Keywords: Antibiotic resistance, Multiple antibiotic resistance, Aquaculture sources,MAR index value, 16S rRNA gene sequencing

Nowadays, combination therapy has become one of the most effective clinical practices in treating infections due to the emergence of multi-resistant microorganisms. In this study, minimum inhibitory concentrations (MICs) of six selected antibiotics; ampicillin, gentamicin, tetracycline, rifampicin, chloramphenicol, and ciprofloxacin were screened towards five Bacillus cereus isolates; KS2, E2, F2, F6, and K2W2 isolated from aquaculture sources and river in Kukup, Johor, Malaysia. Determination of MICs on tested antibiotics showed that all B. cereus isolates were resistant towards ampicillin and rifampicin but most sensitive to chloramphenicol, ciprofloxacin, and gentamicin. Apart from that, this investigation also provides the synergistic effect of ampicillin and chloramphenicol against the B. cereus isolates. On contrary, K2W2 resulted as an antagonism while F6 resulted as indifference. In particular, synergy or double therapy of antibiotics may be required to treat multiresistant organisms. Furthermore, the observed synergy between ampicillin and chloramphenicol opens a new window of using bacteriocins and antibiotics in combination therapy of infections.

The emergence of antibiotic resistant bacteria in aquatic environment has led to an increase in waterborne health risks to an alarming extent. This study attempts to investigate the population of certain antibiotic resistant strains in Peninsular Malaysia. From the samples of 14 rivers from 7 different states in Peninsular Malaysia, a total of 203 isolates were successfully isolated. These are from rivers in Negeri Sembilan, Melaka, Selangor, Kuala Lumpur, Kedah, Kelantan and Terengganu with 35, 15, 37, 39, 24, 26 and 27 isolates, respectively. The isolates were tested for their susceptibility towards 6 broad spectrum of antibiotics which are gentamicin, ampicillin, rifampicin, chloramphenicol, tetracycline, and ciprofloxacin. A total of 117 isolates were identified to have more than 20% MAR index value with 47 of the isolates possess minimum MAR index value of 50%. Based on MAR index value, 59% of isolates are high risk threats indicating a serious emergence of antibiotic resistant bacteria in the rivers in Peninsular Malaysia. Isolates with MAR index value of more than 50% were selected for 16S rRNA gene sequencing for further identification.Based on 16s rRNA gene sequencing, the isolates are a mixture of pathogenic and commensals bacteria. This also implies that the environment especially rivers can be a reservoir for genetic jugglery