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With the increasing rate of antibiotics failure, attention has been drawn to the bacteriophage as an alternative to control multidrug resistant bacteria. Herein, two Salmonella bacteriophages SH1 and SH2, capable of infecting multiple Salmonella serovars, were isolated and characterised. The phages were isolated from chicken fillet samples using the double agar overlay plaque assay by using Salmonella Hvittingfoss as a host bacterium. SH1 and SH2, the double-stranded DNA phages which belong to the family Siphoviridae, were found to have broad host range due to the capability of inhibiting 37 and 38 out of 58 Salmonella strains, which included 17 and 16 different serovars, respectively. Both phages were found to have the optimal multiplicity of infection of 1 with good pH tolerance (pH 5 - 11) and thermal stability (4 - 50°C). For the reproduction cycle, it was discovered that SH1 and SH2 have the latent periods of 20 and 10 min with average burst sizes of 59 and 52 PFU/cell, respectively. A total of 0.31 ± 0.01 and 0.32 ± 0.04 log CFU/mL viable cells of Salmonella host were significantly reduced from the initial count after treatment with SH1 and SH2 for 24 h, respectively. Moreover, SH1 and SH2 were discovered to have an effective eradication effect towards S. Hvittingfoss with a percentage of 99.74 ± 0.17% and 89.40 ± 0.29%, respectively, after 24 h treatment. The present work suggests that SH1 and SH2 could provide a good prevention and control effect against planktonic antibiotic-resistant Salmonella and its biofilms. The present work also describes the potential of both bacteriophages to be used for biocontrol of Salmonella in food owing to their features, particularly the stability and broad host range. [ABSTRACT FROM AUTHOR]

The prevalence of Salmonella in chicken and beef sold in retails outlets in Malaysia was determined by analysing 312 raw beef and chicken meat samples including their processed products. Samples purchased from supermarkets, butcher shops and wet market, which being classified into raw, minced and processed chicken and beef. A total of 86 (27.6%) samples were found positive for Salmonella spp., with chicken meat samples (40.4%) showed greater presence compared to beef (15.4%). Highest presence of Salmonella were detected from wet market samples (35.4%), followed by supermarket (26.9%) and butcher shop (21.3%). The prevalence of Salmonella were higher in unpacked chicken meat (84.8%), followed by unpacked beef (27.8%). Salmonella serovars were identified as S. Enteritidis, S. Hadar, S. Dublin, S. Anatum, S. Stanley, S. Gallinarum, S. Choleraesuis and S. Typhimurium. Detection of 8 Salmonella serovars showed possibilities of cross contamination in various sources either at slaughtering house, processing plant or until storage at retails level. Improper cooking method on meats and hygiene practices prior to consume should be avoided in order to ensure food safety before ingestion. [ABSTRACT FROM AUTHOR]

Bacillus cereus (B. cereus) isolates are toxigenic and can cause food poisoning. Cooked rice is a potentially hazardous food, especially in tropical countries. The aim of this study was to determine the prevalence of B. cereus and B. thuringiensis in raw and cooked rice marketed in Selangor, Malaysia. A combination of Most Probable Number - Polymerase Chain Reaction (MPN-PCR) method was used to detect gyrB gene in B. cereus and B. thuringiensis. Five local varieties of raw rice samples were negative for B. thuringiensis but all (100%) were positive for B. cereus. A total of 115 cooked rice samples (nasi lemak, nasi briyani, nasi ayam and nasi putih) were studied for the presence of B. cereus and B. thuringiensis. Nasi ayam was found to have the highest prevalence (100%) of B. cereus compared to nasi putih (76.2%) and nasi lemak (70.4%). Nasi briyani had the lowest prevalence (50%) of B. cereus. The frequencies of B. thuringiensis were found to be 10, 30 and 35.2 % in nasi putih and nasi ayam, nasi briyani and nasi lemak, respectively. Occurrence of B. cereus and B. thuringiensis in the samples ranged from < 3 to 1100 MPN/g in different samples. Maximum number of B. cereus was observed in nasi lemak, nasi briyani and nasi putih ( > 1100 MPN/g) while nasi ayam showed less contamination (460 MPN/g) with B. cereus which was significantly different (P < 0.05 ) from others. The number of B. thuringiensis in nasi lemak, nasi briyani, nasi putih and nasi ayam were found to be >1100, 93, 9.2 and 3.6 MPN/g, respectively. [ABSTRACT FROM AUTHOR]

Presence of Norovirus in food can cause viral gasteroenteritis. Recently, lots of reports relating to Norovirus in food have been published. Special attention must be paid to the raw foods as they are not subjected to further heat treatment. In this study, pegaga, kesum, tauge and ulam raja (popular salad vegetables in Malaysia) were investigated for Norovirus. A total of 32 samples from each type of salad vegetables were purchased from local market and analyzed using One-step RTPCR (Reverse Transcriptase-Polymerase Chain Reaction) for both genogroups namely Norovirus Genogroup I and Genogroup II. Results showed that tauge had the highest contamination with Norovirus Genogroup I (15.6%) comparing to pegaga (9.4%), kesum (12.5%) and ulam raja (0%). Samples were free from Norovirus Genogroup II. The study showed that raw vegetables are high-risk foods and can be contaminated with Norovirus. [ABSTRACT FROM AUTHOR]

A total of 49 isolates of V. parahaemolyticus and 8 isolates of V. cholerae isolated from freshwater fish of patin (Pangasius hypopthalmus) and red tilapia (Oreochromis sp.) were purchased from different retail level in Selangor, Malaysia. All of the isolates showed a multiple resistances towards all 15 antibiotics tested. Some of the isolates show a high resistance to different antibiotics including bacitracin, vancomycin, tetracycline, furazididone, cephalothin and erythromycin. However, both species was susceptible towards imipenem. Overall antibiotics resistance patterns of all isolates were resistant from 2 to 14 resistance patterns with multiple antibiotic resistance (MAR) index ranging from 0.13 to 0.93 respectively. As the results obtained in the dendrogram produced from both species had indicates that these antibiotics were intensively used whether in the aquaculture farm through feeds during culture or at the hatchery production of seed. Thus, this study will provides an essential information of the MAR index and also the clustering analysis in order to determine the biosafety of Vibrio spp. in freshwater aquaculture fish sold at different retail level in Malaysia. [ABSTRACT FROM AUTHOR]

A time course study on the growth of Salmonella Enteritidis on raw vegetables used a part of the ingredients for sandwiches at room temperature and at 4°C, with initial microbial load of log 3 and log 1 spiked onto the lettuce and cucumber slices. The growth of Salmonella Enteritidis were higher at room temperature and were dose dependent. The information obtained in this study may contribute towards food handling solutions in order to be able to control the food safety of fresh produce. [ABSTRACT FROM AUTHOR]

In this study, the prevalence of Vibrio spp. and V. cholerae in flavored drinks and fruit juices sold at hawker stalls and in restaurants were determined using the most probable number (MPN) method and polymerase chain reaction (PCR) assay. One hundred and twenty drinks samples of four types of drinks (Iced Milk Rose Syrup, n=25; Iced Milk Corn Syrup, n=20; Apple Juice, n=37 and Iced Carrot Milk, n=28) were collected at two different settings; mainly hawker stalls and restaurants. Upon analysis, the prevalence of Vibrio spp. and V. cholerae in fruit juices and flavored drinks for hawker stalls were 93.3% and 36.7%, respectively whereas for the restaurants, were 93.3% and 20% respectively. Overall, the prevalence of Vibrio spp. and V. cholerae in all the drink samples were 93.3% and 28.3% respectively, highlighting the needs for the improvement of the hygiene and sanitation practice in the settings studied. [ABSTRACT FROM AUTHOR]

Little is known on the biosafety level of Vibrio spp. in freshwater fish in Malaysia. The purpose of this study was to investigate the prevalence and concentration of Vibrio spp. and V. parahaemolyticus in freshwater fish using the Most Probable Number-Polymerase Chain Reaction (MPN-PCR) method. The study was conducted on 150 samples from two types of freshwater fish commonly sold at hypermarkets, i.e. Pangasius hypophthalmus (catfish) and Oreochromis sp. (red tilapia). Sampling was done on the flesh, intestinal tract and gills of each fish. The prevalence of Vibrio spp. and V. parahaemolyticus was found to be 98.67% and 24% respectively with higher percentages detected in samples from the gills followed by the intestinal tract and flesh. Vibrio spp. was detected in almost all red tilapia and catfish samples. V. parahaemolyticus was detected in 25% of the catfish samples compared to 22.6% of red tilapia fish. The density of Vibrio spp. and V. parahaemolyticus in the samples ranged from 0 to 1.1x107 MPN/g. Although the maximum value was 1.1x107 MPN/g, most samples had microbial loads ranging from 0 to >104 MPN/g. The outcome on the biosafety assessment of Vibrio spp. and V. parahaemolyticus in freshwater fish indicates another potential source of food safety issues to consumers. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine vegetarian burger patties manufactured by two producers in Malaysia for the presence of Listeria monocytogenes. Brand A was produced by an established food manufacturer while Brand B was produced by a small-scaled food producer. A total of 108 samples of vegetarian burger patties produced by both manufacturers were sampled from retail market and were analyzed by combined MPN-PCR and MPN plating method. Of all the samples tested, ten (9.3%) were found to be contaminated with L. monocytogenes. The L. monocytogenes contamination level in vegetarian burger patties manufactured by producer A (20.9% of the samples were contaminated with 3-1100 MPN/g of L. monocytogenes) was significantly higher (P<0.05) than vegetarian burger patties manufactured by producer B (1.5% of the samples harbored 9.2 MPN/g of L. monocytogenes). Based on the detection and isolation rate obtained with MPN-PCR and MPN-plating, the recovery rate of the L. monocytogenes was estimated to be only 40.0% by MPN-plating approach. [ABSTRACT FROM AUTHOR]