The present study was to evaluate the toxicity of damnacanthal, nordamnacanthal, betulinic acid and zerumbone isolated from local medicinal plants towards leukemia cell lines and immune cells by using MTT assay and flow cytometry cell cycle analysis. The results showed that damnacanthal significantly inhibited HL-60 cells, CEM-SS and WEHI-3B with the IC50 value of 4.0 µg/mL, 8.0 µg/mL and 3.3 µg/mL, respectively. Nordamnacanthal and betulinic acid showed stronger inhibition towards CEM-SS and HL-60 cells with the IC50 value of 5.7 µg/mL and 5.0 µg/mL, respectively. In contrast, Zerumbone was demonstrated to be more toxic towards those leukemia cells with the IC50 value less than 10 µg/mL. Damnacanthal, nordamnacanthal and betulinic acid were not toxic towards 3T3 and PBMC compared to doxorubicin which showed toxicity effects towards 3T3 and PBMC with the IC50 value of 3.0 µg/mL and 28.0 µg/mL, respectively. The cell cycle analysis exhibited that damnacanthal exerted its toxicity effect towards HL-60 cells by inducing apoptosis with value of 25% after 72 hours treatment. Thus, these compounds could be the potential anticancer drug with less toxic side effect.
Broiler part samples (80 fresh and 80 chilled) were examined for the prevalence and numbers of C. jejuni and C. coli by employing most-probable-number (MPN) and polymerase chain reaction (PCR) techniques. The prevalence of the bacteria was high where C. jejuni was detected in 92.5% fresh and 53.8% chilled samples while C. coli in 80.0% fresh and 56.3% chilled. The number of these bacteria in the positive fresh and chilled samples was from 3 to more than 2400 MPN/g and from 3 to 290 MPN/g, respectively. Antibiotic resistance test (using Kirby-Bauer disc diffusion method) on 10 C. jejuni and 13 C. coli isolates toward ampicillin, tobramycin, enrofloxacin, ciprofloxacin, tetracycline, cephalothin, gentamicin and norfloxacin revealed high resistance toward all antibiotics (20.0% - 100.0%). All isolates were resistant to at least two antibiotics. This study highlights the potential of multidrug-resistant C. jejuni and C. coli transmission to humans through fresh and chilled broiler parts. Consecutive studies with bigger sample sizes and covering all over Malaysia are warranted in future.
The aim of this study is to compare antioxidant level and activities (i.e. primary and secondary) in pulps and peels of two species of dragon fruits, Hylocereus undatus (white dragon fruit) and Hylocereus polyrhizus (red dragon fruit). Total phenolic content (TPC) assay demonstrated that peels of both Hylocereus species contained higher phenolic content than the pulps. The phenolic content in peels of H. undatus was higher than H. polyrhizus, but the phenolic content in pulps of H. undatus was much lower than H. polyrhizus. 2, 2, diphenyl-1-picrylhydrazyl (DPPH) assay showed that radical scavenging activities of peels for both species were higher than the pulps. For ferrous ion chelating (FIC) assay, peels and pulps of both Hylocereus species showed moderate metal ion chelating effect as compared to EDTA. Overall, the results suggested that the TPC showed good relationship with the primary antioxidant activities for general comparison between the peels and the pulps.
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.
The aim of this study was to assess the most probable number-polymerase chain reaction (MPNPCR) technique for detection of Listeria monocytogenes in salad vegetables in comparison with reference EN ISO 11290-2 and Food Drug Administration Bacteriological Analytical Manual method using artificial and naturally contaminated samples. Based on recovery of L. monocytogenes from artificially contaminated samples, MPN-PCR showed a moderate correlation (R=0.67) between spiking concentration and microbial levels which was better than the FDA-BAM method (R=0.642) and ISO 11290-2:1998 method (R=0.655). With naturally contaminated samples, it was found that L. monocytogenes was detected in 25% of the vegetable samples using MPN-PCR; 15% of the samples by the FDA-BAM method and 8% of samples using ISO 11290-2:1998 method. Overall, MPN-PCR was found to be a rapid and reliable method that could facilitate the enumeration of L. monocytogenes in vegetables.
The main objective of the present study was to investigate the effects of the frying media and storage time on the fatty acid composition (FAC) and iodine value (IV) of deep-fat fried potato chips. The frying experiment was conducted at 180ºC for five consecutive days. Six frying media were considered as the main treatments: refined, bleached, deodorized (RBD) palm olein (A), canola oil (C), RBD palm olein/sesame oil (AB, 1:1 w/w), RBD palm olein/canola oil (AC, 1:1, w/w), sesame oil/canola oil (BC, 1:1, w/w), and RBD palm olein/sesame oil/canola oil (ABC, 1:1:1, w/w/w). The initial degrees of unsaturation of the consumed oils, A, C, AB, AC, BC, and ABC, were 58.6, 94.0, 68.0, 72.2, 87.7, and 75.8 (g/100 g), respectively. The fatty acid analysis showed that there was a decrease in both the linolenic acid (C18:3) and linoleic acid (C18:2) contents, whereas the palmitic acid (C16:0) increased with a prolonged frying time. The chemical analysis showed that there was a significant (p < 0.05) difference in terms of the IV for each frying oil during the five consecutive days of frying (day 0 to 5). Oil C had the least stability in terms of deep-fat frying due to a high level of unsaturated fatty acids. Conversely, oil AC had the best stability due to the smallest reduction of the C18:2/C16:0 ratio and the IV.
Protein efficiency ratio (PER) and protein digestibility are important parameters used in protein quality determination. Protein nutritive values of selected protein sources: buffalo meat, casein, soy protein isolate, and tempeh, with sodium caseinate as a reference formulation, were evaluated. Determination of proximate analysis, protein quality and protein digestibility were monitored. Procedures for evaluation of protein quality and digestibility included PER using the rat bioassay and in vivo Apparent Protein Digestibility (APD). The rats fed with buffalo meat had the highest mean increase in body weight (102.73g±8.95) while rats fed with tempeh had the lowest mean for increase in body weight (16.34g±9.11). Although the mean for body weight gained showed significant differences between all treatments (P0.05) found between casein and soy protein isolate for total food intake. For the PER value, buffalo meat had the highest value (2.99), followed by sodium caseinate (2.41), casein (1.93), soy protein isolate (1.52) and tempeh (1.10). The PER value for buffalo meat (2.99) was higher than sodium caseinate (2.41) while the rest of the treatment were comparatively lower than sodium caseinate. For the in vivo apparent protein digestibility, tempeh had the highest value (91.41%±3.76), followed by casein (91.34%±3.15), buffalo meat (90.79%±1.44), soy protein isolate (89.52%±2.96) and sodium caseinate (89.47%±2.31).
The antioxidant properties of skin, flesh and kernel of Canarium odontophyllum fruit were determined. The methanolic extracts of the fruit were screened for their total phenolic content and antioxidant properties. The averaged antioxidant properties (mM TE/g FM) in skin, flesh, and kernel of Canarium odontophyllum were 16.46 ± 0.24, 20.54 ± 0.35, and 8.89 ± 0.29, respectively by DPPH assay; 151.24 ± 9.75, 70.58 ± 2.98, and 5.65 ± 0.02, respectively by FRAP assay; and 47.9 ± 0.00, 11.61 ± 1.14, and 3.00 ± 0.00, respectively by β-Carotene bleaching method. The averaged OH scavenging activity (mg DMSOE/mg FM) in skin, flesh, and kernel of Canarium odontophyllum were 43.33 ± 13.85, 7.81 ± 1.42, and 3.31 ± 0.80, respectively. While averaged total phenolic content (mg GAE/100g FM) were 387.5 ± 33.23, 267.0 ± 4.24, and 51.0 ± 0.00 for skin, flesh, and kernel respectively. Antioxidant activities were positively correlated with the total phenolic content (0.71 ≤ r ≤ 0.84).
The whole plant extract of plant Sceletium tortuosum, plant native to South Africa, has been known
traditionally to have mood enhancing and stimulant properties. These properties have been confirmed before by proving serotonin-uptake inhibition activity. A further confirmation by using CB1 receptor binding assay has been performed in this study. The unfermented alkaloid extract was proved to posses a higher activity to bind CB1 receptor compared to that of the fermented one. GC-MS analysis confirmed that unfermented alkoloid extract contain more alkaloids than the fermented one. The ethanol extract was also more active than the fermented one, suggesting that non-alkaloid compounds in this extract could posses this activity. An additional test to check wether this extract can improve cognitive function and memory was performed by acetylcholinesterase inhibitory assay. Both fermented and unfermented alkaloid extracts could inhibit acetylcholinesterase with IC50 being 0.303 mg/ml and 0.330 mg/ml, respectively. However, the major alkaloid in the extract, mesembrine, did not show inhibition of the enzyme. A TLC based test proved that other alkaloids in the extract were responsible to the activity.
Phytates have been considered as a threat in human diet due to its antinutrients behaviour which
known as strong chelators of divalent minerals such as Ca2+, Mg2+, Zn2+ and Fe2+. Phytic acid has a potential for binding positively charged proteins, amino acids, and/or multivalent cations or minerals in foods. The resulting complexes are insoluble, difficult for humans to hydrolyze during digestion, and thus, typically are nutritionally less available for absorption. The reduction of this phytates can be achieved through both enzymatic and nonenzymatic removal. Enzymatic degradation includes addition of either isolated form of wild-type or recombinant exogenous phytate-degrading enzymes microorganisms in the food matrix. Non-enzymatic hydrolysis of phytate occurred in the final food during food processing or physical separation of phytate-rich parts of the plants seed. The application of phytase with respect to breadmaking process, probiotics, animal feed supplement and transgenic crops are emphasised in this paper.
Genetically modified organisms (GMO) are increased remarkably from year to year and the estimated global area cultivated with genetically modified (GM) crops reached 125 million hectares in year 2008. However, insect resistance maize based on Bacillus thuringienses (Bt) is of the most cultivated GM crop in worldwide. Bacillus thuringiensis (Bt) is an aerobic, gram-positive bacterium that synthesize one or more Cry protein that are toxic to various types crop and forestry insects pests. To date, several cry genes have been introduced into GM plant to combat with various type of insect. Worldwide commercialization of GM crops has raised the customers’ concern about the Biosafety issues, and thus, many countries have implemented the labeling legislations for GM food and their derivatives. In this study, we introduced the quantitative analysis method based on the recombinant plasmid DNA as calibrators that can be used to determine the percentage of GMO content in various types of food and feed samples. Therefore, we have reported 7.5% (6/80) of the samples were contained StarLink maize and 1.25% (1/80) samples were contained Bt176 maize. Additionally, the percentage of GM content in each positive sample were further determined with the developed quantitative method. The percentage of the StarLink corns that present in the positive samples were varies from 0.09% to 2.53% and Bt176 corn that present in the positive sample was 16.90%. The present study demonstrated that the recombinant plasmid DNA that used in quantitative real-time method as good alternative quantitative analysis of GM content.
The objectives of this study were predicting the transmission and survival of L. monocytogenes in cooked ham during supply chain. Cooked ham are frequently contaminated with L. monocytogenes during postprocessing steps through contact on surface of processing, handling, packaging equipment. Transfer rate of L. monocytogenes on static and dynamic condition in various surface type was investigated. The prevalence and level of L. monocytogenes in cooked ham at plant as well as the prevalence of unsatisfactory processing at retail were studied. A Monte Carlo simulation model was created by using @risk. The simulation predicted that the prevalence was 11.76 % with 90% confidence interval of 2% to 25% and estimated level was -4.02 log CFU/cm2. It was estimated to be occurred on slicing step at plant. Our results suggest that, the prevalence and level of L. monocytogenes can be reduced by Good Handling Process application and/or HACCP application.
Changes of physico-chemical properties such as size, weight, moisture content, total soluble solid
(TSS), colour, pH, total acidity and sugar content of red seedless watermelon during storage at room temperature (± 28ºC; 70-80% RH) were investigated. The average weight, diameter and length of red seedless watermelon were 5.94 kg, 22.0 cm and 21.8 cm respectively. The length to diameter ratio was 1.02. The statistical analysis indicated that total soluble solids of fruit decreased significantly (p
Caenorhabditis elegans (C. elegans) have been widely used as an infection model for mammalian related pathogens with promising results. The bacterial factors required for virulence in non-mammalian host C. elegans play a role in mammalian systems. Previous reported that Salmonella found in vegetable and poultry meat could be potential health hazards to human. This study evaluated the pathogenicity of various serovars of Salmonella enterica (S. enterica) that recovered from local indigenous vegetables and poultry meat using C. elegans as a simple host model. Almost all S. enterica isolates were capable of colonizing the intestine of C. elegans, causing a significant reduction in the survival of nematodes. The colonization of Salmonella in C. elegans revealed that the ability of S. enterica in killing C. elegans correlates with its accumulation in the intestine to achieve full pathogenicity. Using this model, the virulence mechanisms of opportunistic pathogenic S. enterica were found to be not only relevant for the interactions of the bacteria with C. elegans but also with mammalian hosts including humans. Hence, C. elegans model could provide valuable insight into preliminary factors from the host that contributes to the environmental bacterial pathogenesis scenario.
Forty three (n=43) genomic DNA of Escherichia coli (11 isolates from eggs and 32 isolates from imported beef meats) were characterized by shiga toxin 1 (stx1), enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) and random amplified polymorphic DNA-PCR (RAPD-PCR) analyses. In the shiga toxin 1 (stx1) gene detection with primer stx 1F (5’-TTCTTCGGTATCCTATTCCC-3’) and stx 1R (5’- CTGTCACAGTAACAACCGT-3’), 9 E. coli of beef meats isolates were positive toward sxt1 gene. The results of the ERIC-PCR and RAPD-PCR were analyzed using GelCompar II software. ERIC-PCR with primer ERIC1 (5’-CACTTAGGGGTCCTCGAATGTA -3’) and ERIC2 (5’-AAGTAAGTGACTGGGGTGAGCG-3’) discriminated the E. coli into 6 clusters and 10 single isolates at 80% similarity. RAPD-PCR with primer Gen8 and Gen9, produced 10 clusters and 15 single isolates and 12 clusters and 14 single isolates of 80%, respectively. These results demonstrated that both ERIC-PCR and RAPD-PCR are useful and suitable tools for molecular typing of those isolates examined.
This study evaluated lipid oxidation in refrigerated (±4ºC) duck meatballs treated with novel antioxidants over 21 days of storage. The duck meatballs were treated with a control substance, Cosmos caudatus (ulam raja) or Polygonum minus (kesum) extract, or BHT (butylated hydroxytoluene), and data was collected every three days. These results showed that Cosmos caudatus and Polygonum minus had better antioxidant effects on duck meatballs than BHT or the control. Folding and microbial potency test results were not significantly different among the three antioxidants tested but were better in antioxidant-treated samples than in control samples. However, Cosmos caudatus and Polygonum minus were slightly more effective in preventing microbial growth. This result suggests that Cosmos caudatus and Polygonum minus may be potentially useful natural resources for enhancing the shelf life of duck meatballs.
Proximate content, fatty acid and mineral compositions were determined for the ten species of deepsea fish from Southern Java Ocean and Western Sumatra Ocean, Indonesia. The proximate composition was found to be 23.0-24.8 % protein, 1.9-4.1% fat , 0-1.75 % carbohydrate, 1.7-2.4 % ash and 70.1-72.1% water, whereas the fatty acid compositions consisted of 0.86 - 49.63 % saturated fatty acids (SFA), 0.29 - 50.09 % monounsaturated fatty acid (MUFA) and 2.85 % - 46.32 % polyunsaturated fatty acids (PUFAs). Among them, those occurring in the highest proportions were myristic acid (C14:0, 0.12-7.59%), palmitic acid (C16:0, 0.02–20.5%), stearic acid (C18:0, 0.42–49.19), oleic acid (C18:1, 0.29–50.09 %), linoleic acid (C18:2, 0.23– 44.91%), eicosapentaenoic acid (EPA, C20:5n3, 0.41– 4.61%) docosahexaenoic acid (DHA, C22:6n3, 0.28– 3.44%). The rest of the microelements, Cd, Hg, and Pb were all present in amounts below toxic levels.
This study evaluated the effects of different flours (tapioca, wheat, sago and potato) on the physicochemical properties of duck sausage. The examined physicochemical properties included proximate composition, cooking yield, color (lightness, redness and yellowness), folding, texture profile (hardness, elasticity, cohesiveness, gumminess and chewiness) and sensory properties. The study found that different flours have no effect on the cooking yield of duck sausage. The tapioca formulation showed a mid-range lightness value, folding score and textural properties. Duck sausages made with wheat flour had higher protein content and lightness value and a harder texture. Sausages made with potato flour had a darker color, the lowest folding scores and a softer texture. The addition of sago flour resulted in a higher folding score, greater elasticity and increased overall acceptability of sausage due to higher scores for texture and juiciness. These results show that the properties of duck sausage are influenced by the type of flour used.
Sulfonamides (SAs), synthetic antibiotics, are commonly used by veterinarians in chicken for therapeutic, prophylactic or as growth promoter and halt the growth of bacteria in animal production. Four common SAs, Sulfadiazine (SDZ), Sulfamethazine (SMZ), Sulfamethoxazole (SMX) and Sulfaquinoxaline (SQX), were determined in chicken breast and liver samples using reverse phase HPLC using UV detector at 266nm. The concentration of SAs detected in samples from 11 states in Peninsular Malaysia ranged from 0.006-0.062 µg/g in breast meat samples and 0.08-0.193 µg/g in liver samples. Except for sample from Johor, concentration of SAs in all the samples were lower than MRLs established by Malaysia (0.1 µg/g). Exposure of sulfonamides in Malaysian consumers ranged from 0.002-0.088 µg/kg body wt. /day. The highest value of sulfonamides exposure was found in Johor with an estimated daily intake (EDA) of Sulfamethoxazole (SMX) in Johor.
The objective of this study was to examine the effects of different storage conditions of star fruit (Averrhoa carambola) juice on the activity of acetylcholinesterase in various organs of Sprague Dawley (SD) rats. The effect of oral administration of star fruit on serum lipid profiles was also examined in this study. A total of 15 female rats were assigned into three groups with five animals per group (n=5). The first group served as control group and given only distilled water (vehicle) while the other two groups were given different star fruit preparations, i.e. freshly prepared star fruit juice and after 3 hours storage, respectively. From the results obtained, a significant decrease in the hepatic acetylcholinesterase activity was observed in rats treated with star fruit juice. In conclusion, the star fruit juice at different storage conditions is selectively targeted on the acetylcholinesterase activity in rat liver but not in kidney and heart.