Vibrio parahaemolyticus is a main foodborne disease in seafood and generally seafood is
easily deteriorates in quality of color and flavor. In this study, clove (Syzygium aromaticum)
extract shows potent antibacterial activity against growth of antibiotics resistant Vibrio
parahaemolyticus on seafood samples (cockles and shrimps). Vibrio parahaemolyticus was
artificial contaminates on the samples with 106 CFU/ml. The samples were treated with different
concentration of cloves extract with 10 mg/ml which are 0.5%, 5% and 10% concentration
from methanol food grade extraction in 0 hr, 5 min, 10 min, 15 min, 30 min, 60 min and
120 min. Tab water and deionized water were selected as a negative control. As a result, the
amount of 10 % cloves managed to mitigates the number of V. parahaemolyticus on seafood
samples in 5 minutes and 15 min on both samples. Therefore, our results signify the fact that
cloves can be apply as natural sanitizer which could meet consumer demands for safe and
traditionally consumed either raw without any undesirable effect when applied in the seafood
system industries.
Seafood samples obtained in seafood markets and supermarkets at 11 sites selected from four states in Malaysia were examined for the presence of nine potentially pathogenic species from the genus Vibrio between July 1998 and June 1999. We examined 768 sample sets that included shrimp, squid, crab, cockles, and mussels. We extensively examined shrimp samples from Selangor State to determine seasonal variation of Vibrio populations. Eight potentially pathogenic Vibrio species were detected, with overall incidence in the samples at 4.6% for V. cholerae, 4.7% for V. parahaemolyticus, 6.0% for V. vulnificus, 11% for V. alginolyticus, 9.9% for V. metschnikovii, 1.3% for V. mimicus, 13% for V. damsela, 7.6% for V. fluvialis, and 52% for a combined population of all of the above. As many as eight Vibrio species were detected in shrimp and only four in squid and peel mussels. The overall percent incidence of any of the eight vibrios was highest (82%) in cockles (Anadara granosa) among the seafoods examined and was highest (100%) in Kuching, Sarawak State, and lowest (25%) in Penang, Pulau Penang State, among the sampling sites. Of 97 strains of V. cholerae isolated, one strain belonged to the O1 serotype and 14 to the O139 serotype. The results indicate that the various seafood markets in Malaysia are contaminated with potentially pathogenic Vibrio species regardless of the season and suggest that there is a need for adequate consumer protection measures.
Gelatin from salmon (Salmo salar) skin with high molecular weight protein chains (α-chains) was extracted using trypsin-aided process. Response surface methodology was used to optimise the extraction parameters. Yield, hydroxyproline content and protein electrophoretic profile via sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of gelatin were used as responses in the optimization study. The optimum conditions were determined as: trypsin concentration at 1.49 U/g; extraction temperature at 45 °C; and extraction time at 6 h 16 min. This response surface optimized model was significant and produced an experimental value (202.04 ± 8.64%) in good agreement with the predicted value (204.19%). Twofold higher yields of gelatin with high molecular weight protein chains were achieved in the optimized process with trypsin treatment when compared to the process without trypsin.
Dietary intakes and lifestyle habits during adolescence may predict the occurrence of obesity and other diet-related chronic diseases later in life. The purpose of this study was to determine dietary intake of adolescents in a fishing community in Tuaran District, Sabah. A total of 199 apparently healthy adolescents comprising 94 male and 105 female subjects were purposively selected for the study. The mean age of the subjects was 15.2 f 2.2 years with female subjects having a higher mean age of 15.7 f 2.4 years compared to the males (14.6 k1.8 years). The mean BMI of the subjects was 18.4 f 2.9 kg/m2 with females having a significantly higher BMI (18.9 f 2.8 kg/m2) than the males (17.8 f 3.0 kg/m2). Based on the WHO classification (WHO, 1995), 19.6% of the subjects could be classified as thin while 4.5% were at risk of overweight. Overall for both sexes, intake of energy and most nutrients were below the Malaysian recommended nutrient intake (RNI) levels for adolescents, with the exception of vitamin C and niacin. The male subjects showed higher mean intake for vitamin A, thiamine, niacin and vitamin C than the females. Calcium and iron intake ranked among the lowest levels, at 33.4% and 47.2% respectively of the RNI values for both sexes. The main sources of energy were rice, flour products and tubers while fish and seafood were the chief sources of protein. Majority of the subjects (84%) reported taking breakfast daily, which often consisted of fried noodles, fried banana, doughnuts and coffee. Consumption of snacks was popular and commonly consumed snacks were bread, biscuits, and fried banana. The present study revealed that 25.5% and 14.3% of the male and female adolescents respectively were thin, with majority of them consuming inadequate levels of energy and several key nutrients. The results underscore the need for adolescents to be targeted for nutrition and health education as they go through a period of marked physical, physiological and psychological changes.
The acquisition of Photorhabdus insect-related (Pir) toxin-like genes in Vibrio parahaemolyticus has been linked to hepatopancreatic necrosis disease in shrimp. We report the whole-genome sequences of genetically virulent and avirulent V. parahaemolyticus isolated from a Malaysian aquaculture pond and show that they represent previously unreported sequence types of V. parahaemolyticus.
The Christmas Island red crab, Gecarcoidea natalis, is an herbivorous land crab that consumes mostly fallen leaf litter. In order to subsist, G. natalis would need to have developed specialised digestive enzymes capable of supplying significant amounts of metabolisable sugars from this diet. To gain insights into the carbohydrate metabolism of G. natalis, a transcriptome assembly was performed, with a specific focus on identifying transcripts coding for carbohydrate active enzyme (CAZy) using in silico approaches. Transcriptome sequencing of the midgut gland identified 70 CAZy-coding transcripts with varying expression values. At least three newly discovered putative GH9 endo-β-1,4-glucanase ("classic cellulase") transcripts were highly expressed in the midgut gland in addition to the previously characterised GH9 and GH16 (β-1,3-glucanase) transcripts, and underscoring the utility of whole transcriptome in uncovering new CAZy-coding transcripts. A highly expressed transcript coding for GH5_10 previously missed by conventional screening of cellulase activity was inferred to be a novel endo-β-1,4-mannase in G. natalis with in silico support from homology modelling and amino acid alignment with other functionally validated GH5_10 proteins. Maximum likelihood tree reconstruction of the GH5_10 proteins demonstrates the phylogenetic affiliation of the G. natalis GH5_10 transcript to that of other decapods, supporting endogenous expression. Surprisingly, crustacean-derived GH5_10 transcripts were near absent in the current CAZy database and yet mining of the transcriptome shotgun assembly (TSA) recovered more than 100 crustacean GH5_10s in addition to several other biotechnological relevant CAZys, underscoring the unappreciated potential of the TSA database as a valuable resource for crustacean CAZys.
The aim of this study was to investigate how various diets influence testis maturation stages in mud crab (Scylla olivacea)
broodstock. Morphological and histological assessments were performed in triplicate (10 male crabs each). Daily,
subject crabs were fed a squid (Loligo sp.) and a fish (Decapterus sp.) diet at 5-10% of body weight. Diets were analyzed
following methods from the Association of Analytical Communities (AOAC). In comparison to control (wild) crabs, the
two diets generally did not cause significant differences (p>0.05) in body weight, carapace width and gonadosomatic
index (GSI), except in the GSI of squid-fed crabs (p<0.05). At the end of the experiment, crabs that reached Stage 3 testis
maturation included were 6 fish-fed individuals and 23 squid-fed individuals. Additionally, differences in crude protein
and fat levels across diets influenced the nature of male gonadal development. In conclusion, a squid diet was sufficient
to induce Stage 3 testis maturation in Scylla olivacea within 60 days of culture. Our results prove the usefulness in
developing appropriate feeding regimes for male Scylla olivacea broodstock.
Despite contributing to healthy diets for billions of people, aquatic foods are often undervalued as a nutritional solution because their diversity is often reduced to the protein and energy value of a single food type ('seafood' or 'fish')1-4. Here we create a cohesive model that unites terrestrial foods with nearly 3,000 taxa of aquatic foods to understand the future impact of aquatic foods on human nutrition. We project two plausible futures to 2030: a baseline scenario with moderate growth in aquatic animal-source food (AASF) production, and a high-production scenario with a 15-million-tonne increased supply of AASFs over the business-as-usual scenario in 2030, driven largely by investment and innovation in aquaculture production. By comparing changes in AASF consumption between the scenarios, we elucidate geographic and demographic vulnerabilities and estimate health impacts from diet-related causes. Globally, we find that a high-production scenario will decrease AASF prices by 26% and increase their consumption, thereby reducing the consumption of red and processed meats that can lead to diet-related non-communicable diseases5,6 while also preventing approximately 166 million cases of inadequate micronutrient intake. This finding provides a broad evidentiary basis for policy makers and development stakeholders to capitalize on the potential of aquatic foods to reduce food and nutrition insecurity and tackle malnutrition in all its forms.
An acidic solution containing mercury chelating agents to eliminate mercury in raw fish (mackerel) fillet was developed. The solution contained hydrochloric acid, sodium hydroxide, cysteine, EDTA, and NaCl. The optimum conditions for mercury reduction were achieved using response surface methodology (RSM) at cysteine concentration of 1.25%, EDTA of 275 mg/L, NaCl of 0.5%, pH of 3.75, and exposure time of 18 min. The optimized conditions produced a solution which can remove up to 91% mercury from raw fish fillet. Cysteine and EDTA were identified as potential chelating agents with the greatest potential for use. The solution can be employed in fish industries to reduce mercury in highly contaminated fish.
Seafood is common item in the world diet; Asian countries have the highest rates of fish consumption in the world, which is higher than world average. Several studies have been conducted on the epidemiology and clinical characteristics of seafood allergy in different countries, and some of the fish and seafood allergens unique to those regions have been characterized. Review on published data showed that seafood allergy is very ubiquitous in some regions of the world. Fish and shellfish are the most common seafood that cause adverse allergic reactions among nations; the symptoms ranged from oral allergy syndromes to urticaria and anaphylaxis. The major identified allergens are parvalbumin in fish and tropomyosin in shellfish. Nevertheless, such studies are lacking from some regions with high fish and seafood consumption. Furthermore, the published data are mostly from small groups of populations, which large-scale epidemiological studies need to be performed.
Response surface methodology (RSM) was used to determine the optimum experimental conditions to extract methylmercury from fish samples for GC analysis. The influence of four variables - acid concentration (3-12 M), cysteine concentration (0.5-2% w/v), solvent volume (3-9 ml) and extraction time (10-30 min) - on recovery of methylmercury was evaluated. The detection limit for methylmercury analysis using a microelectron capture detector was 7 ng g(-1) in fish samples. The mean recovery under optimum conditions was 94%. Experimental data were adequately fitted into a second-order polynomial model with multiple regression coefficients (r(2)) of 0.977. The four variables had a significant effect (p < 0.05) on the recovery of methylmercury from a reference material (BCR-463). Optimum conditions for methylmercury extraction were found using an acid concentration of 12.2 M, cysteine concentration of 2.4%, solvent volume of 1.5 ml and extraction time of 35 min. The validation of the developed method to analyze methylmercury in fish samples exhibited good agreement with mercury content in the samples.
Seawater may be contaminated by harmful substances, including toxic elements released by human activities. The present study evaluates the total mercury and methylmercury concentrations and their correlations to fish body size in longtail tuna and short-bodied mackerel from Chendring, Kuantan, at east coast and Kuala Perlis at west costs of Peninsular Malaysia during May to November 2007. Total mercury and methylmercury in muscle tissue of 69 samples of longtail tuna and short-bodied mackerel, ranged from 0.180 to 1.460 μg/g and 0.0.169-0.973 μg/g and 0.251-1.470 μg/g and 0.202-1.352, whereas the methylmercury to total mercury ratio ranged from 70% to 83%, respectively. Samples of both species from the east coast showed higher levels of mercury compared to those from west coast. In all of the locations, significant positive correlations were found between fish body weight and mercury content (R(2) > 0.470). The estimated weekly intake of total mercury and methylmercury from the consumption 66.33 g/week of short-bodied mackerel and 18.34 g/week of longtail tuna (based on local dietry survey) was found to be lower than the maximum limit of 5 and 1.5 μg/kg bodyweight established by FAO/WHO and codex, respectively.
Grouper Iriovirus (GIV) is one of the most devastating viral diseases of marine and cultured groupers worldwide. In the current study, 5 presumptive Malaysian GIV isolates were characterised through PCR amplification of the major capsid protein (MCP) gene and phylogenetic analysis of the sequences. The sequences from the five GIV isolates showed 100% homology with each other and a close relationship with grouper iridovirus isolate (GIV_Tn_352), which was clustered in group 1 together with King grouper iridovirus isolate (KGIV_Cy_346), Singapore grouper iridovirus (SGIV), and Crimson snapper iridovirus isolate (CSIV). The phylogenetic tree also showed different degree of relatedness with other Ranavirus strains which were obtained from the blast of GIV MCP gene in the NCBI database. This study confirmed the GIV isolates from Malaysia are related to other isolates that were reported previously.
The practices of preparing traditional foods in the Arctic are rapidly disappearing. Traditional foods of the Arctic represent a rarity among food studies in that they are meat-sourced and prepared in non-industrial settings. These foods, generally consumed without any heating step prior to consumption, harbor an insofar undescribed microbiome. The food-associated microbiomes have implications not only with respect to disease risk, but might also positively influence host health by transferring a yet unknown diversity of live microbes to the human gastrointestinal tract. Here we report the first study of the microbial composition of traditionally dried fish prepared according to Greenlandic traditions and their industrial counterparts. We show that dried capelin prepared according to traditional methods have microbiomes clearly different from industrially prepared capelin, which also have more homogenous microbiomes than traditionally prepared capelin. Interestingly, the locally preferred type of traditionally dried capelin, described to be tastier than other traditionally dried capelin, contains bacteria that potentially confer distinct taste. Finally, we show that dried cod have comparably more homogenous microbiomes when compared to capelin and that in general, the environment of drying is a major determinant of the microbial composition of these indigenous food products.
The concentrations were ranged from 1.35 ± 0.16 to 2.22 ± 0.34 µg/g (dry weight) and 2.65 ± 0.34 to 4.36 ± 0.53 µg/g (dry weight) for Cd and Pb, respectively, in blood cockle Anadara granosa from four sites of Sabang River, namely, Kampung Sambir, Kampung Tambirat, Beliong Temple, and Kampung Tanjung Apong, which are located at Asajaya, Sarawak, Malaysia. All values exceeded safety limits set by Malaysian Food Regulation (1985). It may be the cause of serious human health problems after long term consumption. Thus, consumer should have consciousness about such type of seafood from mentioned sites and need further investigation.
Duck feet collagen was added to threadfin bream and sardine surimi to study its effect on physicochemical properties such as folding test, gel strength, cook loss, water holding capacity, expressible moisture, texture profile analysis and colour measurement. As compared to commercial fish scale collagen and cow collagen, the addition of duck feet collagen resulted in a significant improvement in the quality of the sardine surimi. Duck feet collagen was able to improve the folding test score of sardine surimi from 3.00 to 5.00; gel strength was increased from 275.70 g.mm to 2682.70 g.mm and hardness of gel was increased from 1.12kg to 6.00kg. Addition of duck feet collagen improved the gel strength of threadfin bream surimi from 1696.70 g.mm to 5579.40 g.mm and hardness of gel was increased from 4.55kg to 10.32kg. Colour of threadfin bream and sardine surimi also improve with the addition of duck feet collagen. The lightness was increased from 66.47 to 66.89 (threadfin bream) and from 62.32 to 63.60 for sardine. The results suggest that duck feet collagen has potential as an alternative source of protein additive for the improvement of the physicochemical properties of low grade surimi.
The presence and distribution of endocrine-disrupting chemicals (EDCs) in the mariculture fish from Pulau Kukup, Johor of Malaysia have been studied along with the impact on human health. Six different species of mariculture fish were collected, due to their high consumption in the Asian region-especially Malaysia, to assess their levels of EDCs. The highest concentration of EDCs detected in the muscle was dexamethasone (2.37-15.84 ng/g) and (0.77-13.41 ng/g), in the liver was dexamethasone (<2.54-43.56 ng/g) and progesterone (2.23-9.78 ng/g), and in the reproductive organ are dexamethasone (<2.54-37.23 ng/g) and caffeine (0.21-18.92 ng/g). The human health risk assessment in the current study suggested that there is no potential risk to the consumer because the hazard index was below 1 (HI
Endocrine disrupting compound (EDC) contamination in food is a global concern. Concerning potential environmental and human health exposed to EDCs via food intake, an experiment was conducted on the selected EDCs concentration in the mariculture fish, Trachinotus blochii (golden pomfret), Lutjanus campechanus (snapper), and Lates calcarifer (sea bass) at Pulau Kukup, Johor. Mariculture activity at Pulau Kukup involves active export of fishes to Singapore and Indonesia. The recovery of BPA (bisphenol A), 4OP (4-octylphenol), and 4NP (4-nonylphenol) were 61.54%-93.00%, 16.79%-17.13%, and 61.24%-71.49%, respectively. Relatively high concentration of BPA was recorded in T. blochii (0.322ng/g), followed by L. calcarifer (0.124ng/g) and L. campechanus (0.023ng/g). Furthermore, 4OP and 4NP were detected only in T. blochii at concentrations of 0.084ng/g and 0.078ng/g, respectively. The results of the present study provide insights on monitoring and managing mariculture activity in relation to environmental protection and food safety.
The intake of heterocyclic amines is influenced by the amount and type of meat and fish ingested, frequency of consumption, cooking methods, cooking temperature, and duration of cooking. In this study, the dietary intake of heterocyclic amines in Malaysia and their main sources were investigated. Forty-two samples of meat and fish were analysed by high-performance liquid chromatography with photodiode array detector to determine the concentration of the six predominant heterocyclic amines, namely: 2-amino-3-methylimidazo[4,5-f] quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f] quinoline(MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f] quinoxaline (4,8-DiMeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f] quinoxaline (7,8-DiMeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Dietary intake data were obtained using a food-frequency questionnaire when interviewing 600 Malaysian respondents. The level of total heterocyclic amines in food samples studies ranged from not detected to 38.7 ng g(-1). The average daily intake level of heterocyclic amine was 553.7 ng per capita day(-1). The intake of PhIP was the highest, followed by MeIQx and MeIQ. The results reveal that fried and grilled chicken were the major dietary source of heterocyclic amines in Malaysia. However, the heterocyclic amine intake by the Malaysian population was lower than those reported from other regions.
Gelatin from fish skin is known to be an alternative source for mammalian gelatin. However, it has weaker properties compared to bovine and porcine gelatin, which limits its use in the industry. The conventional method for fish gelatin extraction requires long production time and could cause serious water pollution and chemical treatments are often being used to enhance the yield of fish gelatin and its properties but it may affect the amino acid content of the gelatin. In this regard, High-Pressure Processing (HPP) is a novel method suggested for fish gelatin extraction. The HPP method is classified as green technology as it requires low electricity throughout the process. This study will discuss the impact of HPP the technique gelatin extracted from fish skin. Skins from four types of fish, namely red tilapia (Oreochromis niloticus), black tilapia (Oreochromis mossambicus), grouper (Epinephelus areolatus) and threadfin bream (Nemipterus tambuloides), were used. High pressure was applied at either pretreatment in citric acid solution or during thermal extraction; and the pressure was maintained at 250 MPa with pressure holding time of 10 minutes and 18 hours of water extraction. Gelatin extract from traditional acid-base method was prepared as a standard for comparison. The study found that there was an increment in the yield of gelatin and the concentration of gelatin extract, and the pre-treatment time was also reduced.