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This study was aimed to optimise the Alcalase® enzymatic hydrolysis extraction of Asiatic hard clam (AHC) (Meretrix meretrix) protein hydrolysate in terms of hydrolysis time, hydrolysis temperature, hydrolysis pH, and concentration of enzyme. Protein hydrolysate produced from AHC (M. meretrix) meat was used to determine the optimum hydrolysis conditions. Hydrolysis of AHC meat was optimised using the Central Composite Design Response Surface Methodology (RSM) (CCD). The relationship between four parameters such as temperature (45 – 65°C), enzyme to substrate concentration (1 – 2%), hydrolysis time (60 – 180 mins), and pH (7.5 – 9.5) to the degree of hydrolysis was investigated. The optimum conditions for enzymatic hydrolysis of AHC meat to achieve the maximum degree of hydrolysis (DH) were observed at 65°C, enzyme to substrate concentration of 1%, hydrolysis time of 60 mins, and pH 7.5. The enzymatic protein hydrolysis of AHC meat was predicted using a two factors interaction (2FI) model. Under these optimum conditions, DH's predicted value was 97.41%, which was close to the experimental value (97.89%). The freeze-dried protein hydrolysate powder was characterized concerning the proximate composition. Proximate analysis revealed that the AHC meat contains 7.92±1.76% of moisture, 2.23±0.89% of crude fat, 1.98±0.82 of ash, and 10.53±0.04% of crude protein. While the Asiatic hard clam protein hydrolysate (AHCPH) composed 9.12±0.02% of moisture, 0.80±0.29% of crude fat, and 27.76±0.10% of ash. The protein hydrolysate produced also contained high protein content (50.09±0.88%) and may serve as a good protein source.

The increase in production of Municipal Solid Waste (MSW) from various sectors of the industry should be taken seriously globally. Efficient waste management has been promoted for a great and clean environment. The industry’s by-products waste such as fish and poultry waste have been gaining researchers interest to seriousness converted it to a valuable commodity like alternative gelatine. Therefore, the review on current waste from industry in Malaysia and its impacts, potentially used of fish and poultry wastes as gelatine-based film using bio-nanotechnology approaches and business opportunities was discussed. Application of nanoparticles in food packaging is growing rapidly worldwide especially the development and implementation of bio-degradable packaging system that works against moisture, gas and microbial barrier is a very useful approach to achieve the mentioned function. Replacement of petroleum-based non bio-degradable plastics by bio-degradable packaging material significantly useful for future application in order to protect human health. This is because the major risk associated with nano-sized components is their potential opposing health effects due to its migration into food.

Vibrio parahaemolyticus (V. parahaemolyticus) is a halophilic, Gram-negative human pathogen known as a leading cause of seafood-derived food poisoning. Due to high contamination rate of seafood in Asian countries, V. parahaemolyticus is considered as a food safety concern. V. parahaemolyticus is able to produce biofilm which is more resistant toward disinfectants and antibodies than its planktonic form. Thirty six V. parahaemolyticus isolates from seafood were tested for their susceptibility using 18 different antibiotics. Two V. parahaemolyticus isolates were resistant to bacitracin, chloramphenicol, rifampin, ampicillin, vancomycin, nalidixic acid, penicillin and spectinomycin. Fourteen V. parahaemolyticus isolates were found to be resistant to bacitracin, tetracycline, rifampin, ampicillin, vancomycin, penicillin and spectinomycin. The remaining two isolates were resistant to more than 2 antibiotics. Majority of the V. parahaemolyticus isolates (97.2%) showed MAR index > 0.2, indicating that these isolates were originated from high risk sources. To investigate effect of three common detergents on antibacterial-resistant V. parahaemolyticus, 16 V. parahaemolyticus isolates resistant to more than 7 antibiotics were selected. V. parahaemolyticus (ATCC 17802) was used as reference strain. Detergents were tested for their minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) and time–kill curves were constructed to assess the concentration between MIC and bactericidal activity of detergents. Detergents D1 (Linear alkyl benzene based) was found to be the most effective with MIC and MBC ranged between 97.656 and 1562.5 μg/ml and 781.25–3125 μg/ml, respectively. The time–kill curves demonstrated that the bactericidal endpoint for resistant V. parahaemolyticus isolates reached after 30 min incubation with D1 at concentration 8 × MIC. The isolate VP003 was killed at 8 × MIC within 0.5 h and the reduction in CFU/ml was 3 log units (99.9%). V. parahaemolyticus biofilms were formed in 96 wells microtiter plates at 37 °C and 24 h-old biofilm were used to test antibacterial activity of detergents. Results showed that biofilm-producing ability of antibacterial-resistant V. parahaemolyticus isolates were inhibited at 1562.5–6250 μg/ml of D1 and eradicated at 3125 – ≥50,000 μg/ml of D1. Detergents showed potential antimicrobial activity against V. parahaemolyticus

The microbial safety of foods continues to be a main concern to consumer, regulatory agencies and food industries around the world. In this study, a total of 394 presumptive vibrios from seafood samples (n=394) consists of cockles (Anadara granosa) ,clams (Mya arenaria), (shrimp) Penaeous spp. and (squid) Loligo opalescens have been isolated. Polymerase chain reaction revealed the 9.14% positive toxr gene, 63.8% of the presence of toxin gene V. parahaemolyticus tdh + , 22.2% trh + , and 5.56% of positive isolates possessing both tdh+ and trh+ while pandemics strain was 83.3% . The sixteen resistant isolates toward seven antibiotics were selected for further study in terms of minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Clove (Syzygium aromaticum), star anise (Illicium verum), lemon leaves (Melissa Officinalis) and curry leaves (Murraya koenigii) have been selected from 20 others herbs and spices because of the potential inhibitory activity against the resistant isolates. Time-kill curves were constructed to assess the concentration between bacteriostatic and bactericidal activity of the respective herbs and spices at concentrations ranging from 0 MIC to 8 × MIC. The activity of cloves against biofilm- producing resistant strains also evaluated. The growth of all resistant strains (n=16) including V. parahaemolyticus ATCC 17802 were inhibited by cloves at a concentration of 39.062 µg/ml and was able to kill all resistant strains with a MBC90 at 78.125 µg/ml compared to the others. The time-kill curves demonstrated that the bactericidal endpoint for resistant strain was reached after 30 min of incubation at a antimicrobials concentration of 8 × MIC. The growth of biofilm-producing isolates can be inhibited and eradicated by clove at concentrations of 156.25 µg/ml, 625 µg/ml respectively. Clove has stronger activity against biofilm-producing resistant strains than star anise, lemon Leaves and curry leaves extracts.

The purpose of this study was to investigate the biosafety of Vibrio parahaemolyticus in raw salad vegetables at wet markets and supermarkets in Malaysia. A combination of the most probable number -polymerase chain reaction (MPN- PCR) method was applied to detect the presence of V. parahaemolyticus and to enumerate their density in the food samples. The study analyzed 276 samples of common vegetables eaten raw in Malaysia (Wild cosmos=8; Japanese parsley=21; Cabbage=30; Lettuce=16; Indian pennywort=17; Carrot=31; Sweet potato=29; Tomato=38; Cucumber=28; Four-winged bean=26; Long bean=32). The samples were purchased from two supermarkets (A and B) and two wet markets (C and D). The occurrence of V. parahaemolyticus detected was 20.65%, with a higher frequency of V. parahaemolyticus in vegetables obtained from wet markets (Wet market C=27.27%; Wet Market D=32.05%) compared with supermarkets (Supermarket A=1.64%; Supermarket B=16.67%). V. parahaemolyticus was most prevalent in Indian pennywort (41.18%). The density of V. parahaemolyticus in all the samples ranged from 2,400 MPN/g, mostly

The aim of this study was to investigate the occurrence of campylobacters in chicken at farms (close-house system and open-house system), slaughtering (conventional slaughterhouse and processing plant) and retail (wet market and supermarket). Campylobacter spp. was not found in cloacal swabs in chickens aged of 4 weeks in farms with close-house system. Campylobacter spp. was found in cloacal swabs (95.0%) in four weeks old chicken in farms with open-house systems. End-slaughtering samples from conventional slaughterhouse and processing plant were contaminated with Campylobacter spp. at 84.0% and 94.0%, respectively. Campylobacter contamination on wet market and supermarket samples with 78.0% and 92.0%, respectively. Close-house system at farm level was able to prevent or delay Campylobacter spp. colonization in chickens but contamination by Campylobacter spp. at retail level was still high. Therefore, monitoring of Campylobacter spp. in chicken products at retail level is crucial to reduce risk of human ingestion of Campylobacter spp. through chicken products.

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.