A total of 78 samples comprising different types of street foods, sold in different locations in Malaysia, were examined for the presence of Enterobacter cloacae. E. cloacae contamination was recorded in 9% of the samples examined. Tests for susceptibility to 12 different antibiotics showed that all were resistant to six or more antibiotics, but susceptible to chloramphenicol and gentamicin. Plasmids of four different sizes were detected from the three plasmid positive isolates. RAPD analysis using four primers yielded completely different banding patterns for all E. cloacae studied. In Malaysia, no published information on street foods in the epidemiological investigation of E.cloacae related disease is available. However, their occurrences have provided compelling evidence that the risk of disease transmission caused by E. cloacae through street foods is moderate.
Studies indicate that bacterial cross-contamination occurs during food preparation where bacteria can retent on the food contact surfaces and cause illness. The study evaluated the adherence of Campylobacter spp. to cutting boards, blades of knives and hands after cutting chilled, raw broiler parts (thighs + drumsticks, wings and livers). The adherence to cucumber cuts that were cut using the unwashed boards and knives was also analyzed. Generally, utensils have higher mean of Campylobacter spp. retained to them (1.4-223.3 MPN/ml rinse) than hands (0.7-43.4 MPN/ml rinse); however, Mann-Whitney U test showed no significant differences in the bacterial numbers found among the different surfaces. The transfer rates of Campylobacter spp. from utensils to cucumber cuts varied from 0% to more than 100%. The bacteria detected could be from the utensils and cucumber contamination before purchase or due to other factors where further investigation is required. The possibility is there for Campylobacter to spread to contact surfaces during chilled broiler handling; therefore, utensils and hands involved should be washed thoroughly especially before ready-to-eat food preparation.
This study aimed to investigate the prevalence and antibiogram of Vibrio parahaemolyticus in processed bivalve molluscs in Kuala Terengganu. A total of 80 seafood samples, namely mussels (n=20), carpet clams (n=20), cockles (n=20) and scallops (n=20), were subjected to PCR and conventional plating method for the detection of V. parahaemolyticus. V. parahaemolyticus was found in green mussels (55%), carpet clam (80%), cockles (40%) and scallops (55%). Fifty-five V. parahaemolyticus isolates were subjected to 9 types antibiotic sensitivity test using discs diffusion method. All isolates were susceptible to Tetracycline and Gentamycin. Isolates showed high resistance towards Vancomycin (52.73%), Penicillin (45.45%) and Amplicillin (32.73%). Resistance towards Amikacin, Ciprofloxacin and Norfloxacin were found to be 1.82%. It can be concluded that local bivalve molluscs were contaminated with V. parahaemolyticus and isolates showed resistance towards certain antibiotics. Therefore, consumption of raw or semi-cooked bivalve molluscs is not advisable.
Vibrio parahaemolyticus is recognized as a frequent causal agent of human gastroenteritis due to the consumption of raw, undercooked or mishandled seafood in many Asian countries. The number of V. parahaemolyticus cases reported is on the rise, and this becomes a concern to the Asian countries as seafood is favoured by Asians. This study aimed to detect and quantify V. parahaemolyticus in raw oysters and to determine the risk associated with the consumption of raw oysters. A total of 30 oyster samples were collected and analysed in this study. MPN-PCR and MPN-Plating methods were employed and carried out concurrently to determine the prevalence of V. parahaemolyticus in raw oysters. The results showed that the prevalence of total V. parahaemolyticus in oysters was 50.00% (15/30) where the MPN/g range was < 3 – > 11000 MPN/g for MPN-PCR method, and 40.00% (12/30) where the MPN/g range was < 3 – 4300 MPN/g for MPN-Plating method. MPN-PCR method was able to estimate the level of virulence (tdh+ and trh+) V. parahaemolyticus in the raw oysters where 10.00% (3/30) of samples were identified to be in a range of 3 – 30 MPN/g. A microbial risk assessment was conducted based on the enumeration data obtained from MPN-PCR method using @risk. The probability of illness annually was 1.76 X 10-6 with a prediction of 31 cases to occur with respect to the exposed Malaysian population, while the rate per 100,000 people was estimated to be at 0.104. In addition, the antibiogram of V. parahaemolyticus was determined using Kirby Bauer Disk Diffusion Test and the results indicated that the isolates were highly resistant towards Bacitracin (100.00%), Vancomycin (100.00%) and were least resistant to Chloramphenicol (8.70%). The MAR index of the isolates ranged from 0.17 to 0.50. In accordance with the results from this study, the consumption of raw oysters is a risk factor for V. parahaemolyticus infection and proactive actions should be taken to reduce the risk of the pathogen in order to improve public health.
Escherichia coli and Escherichia coli O157 were identified from “selom” (Oenanthe stolonifera), “pegaga” (Centella asiatica), beef, chicken, lamb, buffalo, “ulam Raja” (Cosmos caudatus) and “tenggek burung” (Euodia redlevi). The bacteria were recovered using chromagenic agar. Isolated Escherichia coli and Escherichia coli 0157 were further characterized by plasmid profiling and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The virulence genes of the isolates (VT1, VT2, LT, ST, eaeA, inV) that produces pathogenic Escherichia coli and 16S rRNA gene were screened by a multiplex PCR assay. The plasmid profiling analysis showed that out of 176 isolates, only 103 isolates contained plasmids. ERIC-PCR analysis generated amplified products in the range of ~150 bp to > 1000 bp categorizing isolates into a total of 52 different profiles. Multiplex PCR showed that 20 (32.3%) of the isolates carried eaeA gene, 6 (9.7%) isolates possessed inV genes, only 1 (1.6%) have VT2 genes and 1 (1.6%) as well carried VT1 genes, 2 (3.2%) of the isolates harboured LT genes, and only 1 (1.6%) isolate possessed ST genes. There were no correlation between plasmid, ERIC-PCR and virulence genes profiles.
As the society begin to realize the importance of combating antimicrobial resistance, going
back to silver might be the solution. Silver has been known for its potential antimicrobial
activity since ancient times and, the development of nanoparticles has increased its potential
into becoming an antimicrobial agent that can be applied in broad-spectrum. Antimicrobial
resistance has spread into an irrepressible manner which requires drastic action plan as a number
of pathogenic bacteria began to acquire resistance genes. Methicillin Resistant Staphylococcus
aureus (MRSA) is one of the earliest reported resistant clones which is the center of this study.
This study focused on the dissemination and evolution of MRSA on its resistance towards
antibiotics. Disc Diffusion Test was employed to create the antibiograms of MRSA isolates. All
isolates showed resistance towards amoxicillin, ampicillin, cefazolin, oxacillin and penicillin.
In contrast, all isolates were susceptible towards erythromycin. The findings also discovered
isolates that were vancomycin-resistant (66.7%) and vancomycin-intermediate (33.3%). As the
efficacy of antibiotic treatment is at a question, we also investigated on the antimicrobial activity
of colloidal silver in the hope as an alternative treatment. Shiga Toxin producing Escherichia
coli (STEC) and MRSA (ATCC 33591) was tested using modified Quantitative suspension
test for the evaluation of bactericidal activity for chemical disinfectants and antiseptics based
on BS EN 1276:2009. The outcome of this study indicated that the colloidal silver is working
effectively against STEC and MRSA (ATCC 33591), showing killing percentages well above
99.0% at 4 minutes and 8 minutes of contact. Vancomycin-resistant S. aureus (VRSA) and
Vancomycin-intermediate S. aureus (VISA) were also tested and the results indicated that
VISA had higher killing percentages at 4 minutes (99.83%) and 8 minutes (99.85%) compared
to VRSA at 4 minutes (96.72%) and 8 minutes (98.35%). This opens a solution to the rising
problem of antimicrobial resistance.
Vibrio parahaemolyticus is well known to be abundantly distributed in marine, coastal and
estuarine environments. Since 1951, V. parahaemolyticus had been the source of numerous
outbreaks related to contaminated or mishandled seafood. However, V. parahaemolyticus
had been detected on other types of food. This issue has prompted this study to investigate
on the prevalence of V. parahaemolyticus in various food samples and determine the risk
associated with it. The results of the MPN-plating technique of the study indicated that V.
parahaemolyticus was detected in seafood (33.3%, 95% Confidence Interval [CI] 31.9 – 34.8 ,
94 – 290 MPN/g) and vegetables (10.0%, 95% CI 9.7 – 10.3 , 9.2 – 23 MPN/g) while negative
V. parahaemolyticus was detected in fruits (0.0%, 95% CI 0 – 1,
The aim of this work was to investigate the antioxidant and antimicrobial of Phyllanthus amarus, Phyllanthus niruri and Phyllanthus urinaria. P. niruri was found to possess the highest antioxidant activity, the activity decreased in the order P. niruri > P. amarus > P. urinaria for water extract. However, the activity decreased in the order P. niruri > P. urinaria > P. amarus for methanol extract. The result correlation between the antioxidant activity and total phenolic content revealed a positive correlation of 0.954 < r 2 < 1.000 for both water and methanol extract. Methanol extract showed higher total phenolic content and antioxidant activity as compared with water extract. Lowest Minimum Inhibitory Concentration (MIC) value for water extract against the selected microorganism was >2.5 mg/mL meanwhile, for methanol extract was 2.5 mg/mL and >0.625 mg/mL were the value for water and methanol extract. Methanol extract showed better inhibition potential than water extract
Escherichia coli O157:H7 is a major food-borne pathogen that has resulted in numerous
outbreaks around the world. Widespread distribution of the organism in various ecological
niches impedes the control measures. This study aimed to detect and quantify E. coli O157:H7
in beef sold in wet markets and hypermarkets in Malaysia and to determine the risk of E. coli
O157:H7 infection linked to consumption of beef. The rfbO157 and flicH7 primers targeted on
somatic antigen (O157) and flagellar antigen (H7) respectively of E. coli O157:H7 was used for
the MPN-PCR method. A total of 99 beef samples were collected from local wet markets and
hypermarkets. The highest E. coli O157:H7 contamination rate was observed in beef samples
collected from wet markets (89.50%), whereas the contamination rate in hyper market A and B
were compratively low (35.35 and 20% respectively). However, the microbial load was highest
in the beef samples from hypermarket A (1100 MPN/g) while E. coli O157:H7 bacterial load
in beef samples from hypermarket B and wet market ranged from 3 to 93 MPN/g and 3 to 240
MPN/g, respectively. Using the Quantitative Microbial Risk Assessment (QMRA) approach
the risk was estimated incorporating the findings of the prevalence study and predictions
based on home storage, cooking and consumption patterns. Three different exposure pathways
were investigated to estimate the risk associated with contaminated beef and Monte Carlo
simulation was used to determine the level of uncertainty. The developed model predicated that
consumption of contaminated beef can be accountable for 1.83E+06 E. coli O157:H7 cases per
year in Malaysia. The reliability of the model, data gaps and further research needs, is discussed.
Through continuous improvement Quantitative Microbial Risk Assessment provides valuable
insight into controlling and prevention strategies.
Cross contamination is one of the most important contributing factors in foodborne illness
originating in household environments. The objective of this research was to determine the
transfer between naturally contaminated chicken liver and leg to cutting board, hand glove,
knife and cucumber, during slicing. The microorganism tested was Campylobacter jejuni and
the results showed that the pathogen transferred to all utensils, at different transfer rate, despite
the low level of the naturally contaminating pathogen. With unknown concentration bacteria in
the naturally contaminated samples, a proportion of the utensils were still contaminated with C.
jejuni and not surprisingly, when the sample were contaminated with higher concentrations of
the pathogen, a higher proportion of the utensils had detectable C. jejuni cells present, though
in many cases cross contamination seems to be a random event. Transfer of the naturally
contaminating C. jejuni from the chicken liver and leg to the utensils were
Vibrio parahaemolyticus is a halophilic Gram-negative bacterium that is considered among
gastrointestinal pathogens. Thirty isolates were tested for their susceptibility using 14 different
antibiotics. One V. parahaemolyticus isolate was resistant to 10 antibiotics (cefotaxime,
ceftazidime, tetracycline, amikacin, ciprofloxacin, levofloxacin, ofloxacin, ampicillin,
amoxicillin-calv-acid, and cefepime). The V. parahaemolyticus isolates were resistant to
ampicillin (90%), amoxicillin–clavulanic acid (63.3%), cefotaxime (60%), ceftazidime (46.7%),
cefepime (50%), tetracycline (36.6%), and amikacin (26.7%). However, the isolates were highly
susceptible to imipenem (100%), and piperacillin and gentamicin (96.7%). Approximately
55% of the isolates showed a multiple antibiotic resistance (MAR) index of >0.2, thereby
indicating the high risk of sources where these isolates originated. The occurrence of MAR
asserted the importance of determining drug susceptibility and monitoring the antimicrobial
resistance profile to improve and ensure food safety and public health.
Food labeling in accordance with Novel Food Regulation has been enforced in the European Community since 1997 with a series of updated legislations namely, EC/258/97, EC/1139/98, EC/49/2000, EC/50/2000 and EC/1829/2003. Guidelines and labeling regulations for the use of GMOs materials in food and feed products has also been introduced in Malaysia and Vietnam. Therefore, the demand for the establishment and development of a robust and rapid operation procedure for GMO detection has increased recently in both countries. The procedure of GMO detection emphasizes not only on detection tests but also on confirmation assays. This study employed PCR technology for detection and direct DNA sequencing for confirmation procedures respectively. The results demonstrated for the first time the presence of GM plants with glyphosate-resistant trait led by the control of P35S promoter and NOS terminator in either Malaysian or Vietnamese feed with high frequency (20 positive samples out of 24 analyzed samples). The P35S promoter, EPSPS gene and NOS terminator sequences obtained showed some mutations on single-stranded and double-stranded targeted sequences caused by single nucleotide insertion or single nucleotide changes. These results reinforce the need for development of detection procedures to comply with food/feed labeling system.
The ability to detect the presence of transgenes in crop-derived foods depends on the quantity and quality of DNA obtained from a product to be analyzed. The efficiency of DNA extraction protocols differs due to the nature of each food product. In this paper, we described two main DNA extraction protocols and their modifications that have been applied and evaluated for DNA extraction from raw and processed food as well as animal feed. The yield and quality for five categories of food and feed samples namely, raw soybean, raw maize, animal feed, smooth tofu and soymilk are discussed. The statistical interaction analyses showed that the cetyltrimethyl ammonium bromide (CTAB) method was proven to be the best method to extract DNA from raw soybean, maize and animal feed samples which not only obtained high DNA yield of 32.7, 28.4 and 33.4 ng DNA/mg sample respectively, but also produced high quality DNA with the absorbance A260/A280 ratio of 1.9, 1.9 and 2.0, respectively. These DNA were suitable for PCR amplification which produced a 164 bp DNA fragment of the lectin gene from soybean, and a 277 bp DNA fragment of the zein gene from maize. In the processed food category, the Wizard isolation method was found to be the best for the extraction of DNA from smooth tofu and soymilk with the yield of 13.2 and 3.4 ng DNA/mg sample, and the quality of the DNA at the absorbance A260/A280 ratio ranged from 1.9 to 1.7. These DNA were successfully amplified using primers specific to the lectin gene of soybean.
Vibrio parahaemolyticus is one of the most widely recognized pathogenic Vibrio species due to numerous outbreaks and its’ wide occurrence in marine environment. In this study, 32 isolates of V. parahaemolyticus isolated from cockles were tested for sensitivity to 16 antibiotics and the presence of plasmids. All the isolates were multi-resistance, defined as resistant to atleast three different antibiotics with multiple antibiotic resistance indexes ranging from 0.31 to 0.69, indicating the isolates originate from high risk sources of contamination where antibiotics are often used. In the plasmid profiling test, only 15 isolates (47%) harbored plasmid DNA, which ranged in size from 2.7 to 56.2 kb, separating the isolates into 14 plasmid profiles. Hence, food contaminated with antibiotic resistant V. parahaemolyticus could be a major threat to public health due to the distinct possibility that they can be a significant reservoir of genes encoding antibiotic resistance determinants that can be transferred intra or interspecies. As in many developing countries, raw food hygiene and antimicrobial resistance epidemiology is still in the infancy stage in the locality of the study and thus our data provide a current baseline profile of antimicrobial resistance and plasmid of V. parahaemolyticusfrom cockles in Padang, Indonesia.
Biochemical analysis was carried out for pH profiles, freshness in terms of K-values, amino acids profiles, total volatile bases (TVB), total volatile acids (TVA) and biogenic amines for fresh and preserved Macrobrachium rosenbergii. Results showed that pH profiles of Macrobrachium rosenbergii explain the inability of this parameter to be used to evaluate the quality of Macrobrachium rosenbergii. Thus changes in pH profiles of Macrobrachium rosenbergii should be combined with indicators such as total volatile acids and total volatile bases. Total volatile acids of the shrimps increased steadily in small amounts throughout the storage period. A rapid increase in TVB at 100C was detected due to the increase in total aerobic bacteria at elevated temperatures. The microbial activities caused the decrease in the amino acids arginine, lysine and histidine which correlated well with the increase in the corresponding biogenic amines such as putrescine, cadaverine and histamine respectively. Preservatives used in this study controlled the production of these biogenic amines without significantly altering the pH of preserved shrimp.
This cross sectional study aimed to explored the pattern of socio-demographic distribution, to assess the level of KAP of food safety; and the relationship with the level of premise cleanliness in the food courts at Putrajaya. Distribution of food handlers socio-demographic profile was Malaysian (62.0%), male (70.4%), working experienced in food industry (82.0%) and attended food handler training (85.0%). The mean age was 28.7 years and 85.4% having income not less than RM 1,500 monthly. 78.5% of the food handlers at educational level were found as primary/secondary school. 15.0% of the respondents had not attended the food sanitation training. The findings reveal that food handlers’ KAP were high with a mean percentage score more than 79.0%.The majority of the food courts in Putrajaya had consistently moderate level of cleanliness (63.5%) with the mean of 83.03%. Only 27.4% of the food courts were in the level of clean situation (>89% of premise cleanliness score) and 9.1% were not in the clean condition (
The continued and increasing development of antimicrobial resistant bacteria among the
foodborne pathogens had caused worldwide to be alarmed. Being the earliest to develop
antimicrobial resistance, Staphylococcus aureus is constantly monitored for any new
resistance development. The resistance development is often linked to wastewater and the
treatment plants where the pressure of antibiotic is the highest. Hence, this study
investigated on the prevalence of high antimicrobial resistant S. aureus in the wastewater
eluted from a poultry slaughterhouse. A total of thirty wastewater samples were collected
from a poultry slaughterhouse in Semenyih, Selangor. Most probable number (MPN)-
plating method was employed to enumerate the S. aureus count in the wastewater. The
results indicated that S. aureus was highly present whereby all samples (100%) were
positive and the concentration ranged between 11 – 2.1 x 104 MPN/ml. Isolated S. aureus
strains were screened for their antimicrobial susceptibility using the Kirby-Bauer Disk
Diffusion Test method to classify their antimicrobial resistance eleven antibiotics. The
MAR index measured was between 0.18 and 0.91, inferring that the strains are highly
antimicrobial resistance. All S. aureus strains were 100% resistant to ampicillin (25 µg)
and cefazolin (30 µg). 94.1% of the strains were resistant to penicillin (10 µg) which
phenotypically indicated these strains are Methicillin-resistant S. aureus (MRSA).
Notably, 17.6% of the strains developed resistance to vancomycin and was categorized as
Vancomycin-resistant S. aureus (VRSA). There is a need to take drastic preventive
measures to control the resistance development in S. aureus to conserve public health.
Street food is popular in Asia due to its availability, low price and good taste. The safety of
street food has been always questionable due to its poor handling which probably leads to
microbial contamination. The objective of this study was to determine the surviving quantities
of V. parahaemolyticus under various conditions in street-vended food, namely satar and otakotak
after anticipated cross-contamination to support policy and regulatory documents. The
satar and otak-otak were prepared from minced and unminced fish flesh, respectively, together
with other ingredients. Each satar and otak-otak were prepared with 0, 0.5, 1.5 and 3% of
sodium chloride (NaCl), respectively. V. parahaemolyticus inoculum at approximately 8.66 log
CFU/ml were inoculated into the samples and incubated for up to 6 h. Samples were taken at 0,
1, 3 and 6 h for enumeration of V. parahaemolyticus using spread plate method on Thiosulphate
Citrate Bile Salts Sucrose (TCBS) agar. For control samples, V. parahaemolyticus was not
immediately inactivated in distilled water even though significant better survivability was
observed in Phosphate Buffer Saline (PBS). The numbers of V. parahaemolyticus was found
to decrease by varying amounts based on the salt content and duration of holding. However,
significant amounts survived to indicate potential risk.
Listeria monocytogenes is a gram positive, facultative intracellular pathogen with the capacity to cause
food poisoning outbreaks as well as severe illness in vulnerable human population groups. It can cause a rare but serious disease called listeriosis with high fatality rates (20–30%) compared with other foodborne microbial pathogens. Although Listeria monocytogenes is infective to all human population groups, it is more likely to cause severe problems among pregnant women, immunocompromised individuals, the elderly and neonates. There are a variety of phenotyphic and genotyphic methods for the detection of Listeria monocytogenes in foods. Recent technological advances have increased the ability of scientists to detect Listeria monocytogenes. The purpose of this review is to discuss molecular characteristics of the Listeria monocytogenes pathogen, standard detection methods of this pathogen in foods based on culture methods, confirmation of species and subtyping based on phenotypic and genotyphic methods.
Listeria monocytogenes (L. monocytogenes) is a serious food-borne pathogen for immunocompromised individuals. L. monocytogenes is capable of producing biofilm on the surface of food processing lines and instruments. The biofilm transfers contamination to food products and impose risk to public health. Transfers contamination to food products, and impose risk hazard to public health. The aim of this study was to investigate biofilm producing ability of L. monocytogenes isolates. Microtitre assay was used to measure the amount of biofilm production by ten L. monocytogenes isolates from minced chicken / meat, sausages and burgers. Results showed that all 10 L. monocytogenes isolates were able to form biofilm after 24 h at 20˚C on polystyrene surface (the common surface in food industries). Some strains were capable of forming biofilm more than the others. All strains showed a slight raise in the quantities of attached cells over 48 and 72 h. L. monocytogenes strains isolated from minced chicken, minced meat and burgers were better biofilm-producers comparing to the strains isolated from sausages.