Occurrence of Multiple Mycotoxins in Various Types of Rice and Barley Samples in Thailand.

Contamination with multiple mycotoxins was found in rice and barley. BEA, DAS, ZEA, and aflatoxins were the mycotoxins most frequently found in samples. The assessed mycotoxin exposure does not represent a health risk for consumers

Multiclass analysis of antimicrobial drugs in shrimp muscle by ultra high performance liquid chromatography-tandem mass spectrometry

A reliable, selective and rapid multiclass method has been developed for the simultaneous determination of 55 antibacterial drug residues in shrimp muscle samples by ultra high performance liquid chromatography-tandem mass spectrometry. The investigated compounds comprise of eight different classes, namely fluoroquinolones, sulfonamides and synergistic agents, tetracyclines, macrolides, lincosamides, penicillins, nitroimidazole and amphenicols. A simple liquid extraction procedure was developed consisting of extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA), followed by a defatting step with n-hexane. Chromatographic conditions were optimized, obtaining a running time <10 min. Mean recoveries ranged from 74.3% to 113.3%. For precision test, relative standard deviations (RSD, %) were lower than 15.0% and 24.0% for repeatability and reproducibility, respectively. Limits of detection and quantification ranged from 1.0 to 5.0 ng/g and 3.0–10.0 ng/g, respectively. Finally, the method was applied to real samples and the results demonstrated that enrofloxacin, ciprofloxacin, pefloxacin and doxycycline were quantifiable in shrimp samples. Keywords: Antimicrobial drugs, Multiclass analysis, Shrimp, UHPLC-MS/M

Storage Fungi and Mycotoxins Associated with Rice Samples Commercialized in Thailand

The study focused on the examination of the different fungal species isolated from commercial rice samples, applying conventional culture techniques, as well as different molecular and phylogenic analyses to confirm phenotypic identification. Additionally, the mycotoxin production and contamination were analyzed using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS). In total, 40 rice samples were obtained covering rice berry, red jasmine rice, brown rice, germinated brown rice, and white rice. The blotting paper technique applied on the 5 different types of rice samples detected 4285 seed-borne fungal infections (26.8%) for 16,000 rice grains. Gross morphological data revealed that 19 fungal isolates belonged to the genera Penicillium/Talaromyces (18 of 90 isolates; 20%) and Aspergillus (72 of 90 isolates; 80%). To check their morphologies, molecular data (fungal sequence-based BLAST results and a phylogenetic tree of the combined ITS, BenA, CaM, and RPB2 datasets) confirmed the initial classification. The phylogenic analysis revealed that eight isolates belonged to P. citrinum and, additionally, one isolate each belonged to P. chermesinum, A. niger, A. fumigatus, and A. tubingensis. Furthermore, four isolates of T. pinophilus and one isolate of each taxon were identified as Talaromyces ( T. radicus, T. purpureogenum, and T. islandicus). The results showed that A. niger and T. pinophilus were two commonly occurring fungal species in rice samples. After subculturing, ochratoxin A (OTA), generated by T. pinophilus code W3-04, was discovered using LC-MS/MS. In addition, the Fusarium toxin beauvericin was detected in one of the samples. Aflatoxin B1 or other mycotoxins, such as citrinin, trichothecenes, and fumonisins, were detected. These preliminary findings should provide valuable guidance for hazard analysis critical control point concepts used by commercial food suppliers, including the analysis of multiple mycotoxins. Based on the current findings, mycotoxin analyses should focus on A. niger toxins, including OTA and metabolites of T. pinophilus (recently considered a producer of emerging mycotoxins) to exclude health hazards related to the traditionally high consumption of rice by Thai people

An overview of the toxicology and toxicokinetics of fusarenon-X, a type B trichothecene mycotoxin

Fusarenon-X (FX) is a type B trichothecene mycotoxin that is frequently observed along with deoxynivalenol (DON) and nivalenol (NIV) in agricultural commodities. This review aims to give an overview of the literature concerning the toxicology and toxicokinetics of FX. FX is primarily found in cereals grown in temperate regions, but it can also be found worldwide because of the global transport of products. The major toxicity of FX occurs through inhibition of protein synthesis, followed by the disruption of DNA synthesis. Moreover, FX has also been shown to induce apoptosis in in vitro and in vivo studies. The targets of FX are organs containing actively proliferating cells, such as the thymus, spleen, skin, small intestine, testes, and bone marrow. FX causes immunosuppression, intestinal malabsorption, developmental toxicity, and genotoxicity. In addition, sufficient evidence of carcinogenicity in experimental animals is currently lacking and the International Agency for Research on Cancer (IARC) classifies it as a group 3 carcinogen

Heavy metal concentrations in duck eggs and potential human health risk via consumption

Heavy metals commonly found in environmental matrices are from natural or anthropogenic activities. Their contamination effects especially on human health from non-degradable properties are of major concern. The aims of this study, thus, were to determine Cd, Cu, Fe, Mn, Ni, Pb and Zn residues in duck eggshells, yolk and albumin, and to investigate the correlations of these metal residues with the surrounding environmental media (soil, water, and feed). Target hazard quotient (THQ) of individual heavy metal was used to evaluate potential human health risk via egg consumption. Thirty duck egg samples were randomly collected from each free range laying duck farm (total of 8 farms). The samples collected were analyzed for heavy metal concentrations using the flame atomic absorption spectrometry (FAAS). Results showed that average concentrations of Fe (71.96±1.33 μg/g dw) in yolk and Pb (6.76±0.21 μg/g dw) in albumin were significantly highest when compared to other investigated metals, whereas Cu concentration was mostly found in egg shells. In addition, the predominantly found metal in soil samples was Fe, whereas in water and feed samples were Ni and Pb, respectively. Principle component analysis (PCA) revealed that the concentrations of heavy metals found in eggshells and egg contents are highly correlated with their concentrations in the surrounding water and soil matrices as well as feed. The THQs for Pb, which were greater than 1, indicated that there could be potential for human health risks upon consumption of contaminated duck eggs

Using Nassarius stolatus as a potential heavy metal biomonitor

Nassarius stolatus was evaluated as the potential heavy metal (Cd, Fe, Mn, Ni and Pb) accumulator in Don Hoi Lot sandbar, Samut Songkhram province, Thailand. This selected species belongs to the Gastropoda, which is widely distributed in the coastal areas from the upper Gulf through the southern part of Thailand. From our findings, the heavy metal accumulations in N. stolatus tissues were Fe ＞ Pb ＞ Mn ＞ Ni ＞ Cd. The retrieved bioaccumulation factor (BAF) indicated that N. Stolatus has high potential to be a biomonitor for the contaminations of Fe and Mn in water and Cd, Ni and Pb in sediment

Toxicokinetics and tissue distribution of nivalenol in broiler chickens

Nivalenol (NIV), a type B trichothecene mycotoxin, is mainly produced by the fungi of Fusarium genus, which naturally occurs in agricultural commodities. Consumers are particularly concerned over the toxicity and safety of NIV in food animal products. To evaluate the toxicokinetics and persistence of residues of NIV, NIV was administered intravenously (iv) or orally (po) to broiler chickens at a dosage of 0.8 mg/kg body weight. The concentration of NIV in the plasma and various tissues was detected using liquid chromatography tandem-mass spectrometry. The plasma concentration of NIV in broilers could be measured up to 24 h and 12 h after iv and po administration, respectively. The value of elimination half-life of NIV was 5.27 ± 0.82 h and 2.51 ± 0.88 h after iv and po administration, respectively. The absolute oral bioavailability was 3.98 ± 0.08%. NIV was detected in the intestine, kidney, muscle, heart and liver after po administration. Regarding tissue residues, largest quantities of NIV were found in the small intestine. These results suggest that NIV is absorbed from the gastrointestinal tract with low bioavailability and it has the ability to diffuse into various tissues of broilers

Dispositions and tissue residue of zearalenone and its metabolites α-zearalenol and β-zearalenol in broilers

Zearalenone (ZEA) is a secondary fungal metabolite produced mainly by a Fusarium graminearum. To clarify the toxicokinetics, and residues of ZEA and its major metabolites α-zearalenol (α-ZOL) and β-zearalenol (β-ZOL) in chickens, ZEA was then administered intravenously (iv) or orally (po) to broiler chickens at a dosage of 1.2 mg/kg body weight. The concentrations of ZEA, α-ZOL and β-ZOL in the plasma and various tissues were quantified using LC–MS/MS. The plasma concentrations of ZEA were measurable up to 2 h after iv and po administration, and the concentrations of α-ZOL and β-ZOL were detected up to 4 h after both types of administration. A two-compartment model was developed to describe the toxicokinetic of ZEA in broilers. The values of t1/2β and Vd were 1.36 ± 0.29 h and 6.40 ± 0.89 l/kg, respectively. The absolute oral bioavailability was 29.66 ± 5.6%. ZEA, α-ZOL and β-ZOL were measurable in the vital organs after po administration. These results suggest that ZEA is absorbed from the gastrointestinal tract and it has ability to penetrate into the various tissues of broiler chickens