Demand for milk has increased in Malaysia due to the increased in awareness of healthy foods consumption.
Hence, research of milk is crucial to ensure that it is not contaminated with Escherichia coli. This study
evaluated the survival of Escherichia coli at different temperature and haemolysin activity of Escherichia
coli on blood agar. A total of 8 samples of raw fresh and pasteurized milk were collected from nearby farm
and market in Negeri Sembilan, Malaysia. After an overnight exposure to four different temperatures of
0
0C, 280C, 350C and 450C, the bacteriological test of milk was evaluated for the presence of Escherichia
coli. Overall, all raw fresh milk sampled exceeded the acceptable limit of bacterial count of 1 x 105 CFU/ml.
Raw fresh milk recorded the highest count at 35oC with 4.4 x 107 CFU/ml and the lowest at 0oC with 8.3 x
104 CFU/ml. The presence of Escherichia coli was detected in 7/20(35%) of the total raw fresh milk
samples. All pasteurized milk showed no presence of Escherichia coli due to the effectiveness of heat
treatment. Haemolysin test showed no haemolytic activity. Milk contaminated with Escherichia coli can
cause diarrheal, gastrointestinal diseases and urinary infection. Hence, it is important to study the survival
rate of Escherichia coli and its pathogenicity in milk to ensure public safety.
Smoked food was one of the most authentic dishes in Malaysian cuisines. However, local consumers were still unaware on the hygienic level of these smoked products. Nowadays, the smoked products were smoked in an open space that allowed the contamination of bacteria on the food. This study aimed to determine the occurrence and antibiotic resistance of Salmonella in the smoke catfish and meat at the local street stalls in Kuala Pilah, Negeri Sembilan by MPN-PCR methods. The microbial concentration of Salmonella sp. in smoked catfish was 2.4 x 10-8 MPN/g in smoked catfish and 2.9 x 10-7 MPN/g in smoked meat and were confirmed by culturing on selective agar of Salmonella Shigella agar. The prevalence of Salmonella sp. was found to be 68% in both samples by MPN-PCR approach. Salmonella sp. were 100% detected in smoked catfish followed by smoked meat by 44% respectively. All the positive isolates from MPN-PCR were continued with antibiotic susceptibility to determine the resistance level of Salmonella sp. towards selected antibiotics. As result, the isolates showed a multi-resistance patters from one to four antibiotics tested with MAR indices ranging from 0.25 to 1.00. The outcome indicated a high rate of foodborne pathogens which indicated the need to create the awareness on the safety and proper handling of smoked products to minimization of any potential health hazard caused by this foodborne pathogen.
Salmonellosis outbreaks involving typhoid fever and human gastroenteritis are important diseases in tropical countries where hygienic conditions are often not maintained. A rapid and sensitive method to detect Salmonella spp., Salmonella Typhi and Salmonella Typhimurium is needed to improve control and surveillance of typhoid fever and Salmonella gastroenteritis. Our objective was the concurrent detection and differentiation of these food-borne pathogens using a multiplex PCR. We therefore designed and optimized a multiplex PCR using three specific PCR primer pairs for the simultaneous detection of these pathogens. The concentration of each of the primer pairs, magnesium chloride concentration, and primer annealing temperature were optimized before verification of the specificity of the primer pairs. The target genes produced amplicons at 429 bp, 300 bp and 620 bp which were shown to be 100% specific to each target bacterium, Salmonella spp., Salmonella Typhi and Salmonella Typhimurium, respectively.