Search results for "010401 analytical chemistry"
showing 10 items of 1284 documents
Study on mycotoxin contamination of maize kernels in Spain
2020
Abstract Mycotoxins are secondary metabolites produced mainly by fungal species belonging to the genera Fusarium, Aspergillus and Penicillium and belong to the most relevant contaminants of food and feed. Cereals are the main source of mycotoxins in the diet. The most prominent mycotoxins are aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1 and AFG2), fumonisins B1 and B2 (FB1 and FB2), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), 3- and 15-acetyl-deoxynivalenol (3- and 15-ADON), and T-2 and HT-2 toxins. Maximum levels allowed in food are very different depending on mycotoxin and food type, consumer susceptibility and current legislation in each country. Among cereals, maize a…
Ultra-High-Performance Liquid Chromatography Coupled with Quadrupole Orbitrap High-Resolution Mass Spectrometry for Multi-Residue Analysis of Mycotox…
2020
Cannabidiol (CBD) food supplements made of Cannabis sativa L. extracts have quickly become popular products due to their health-promoting effects. However, potential contaminants, such as mycotoxins and pesticides, can be coextracted during the manufacturing process and placed into the final product. Accordingly, a novel methodology using ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) was developed to quantify 16 mycotoxins produced by major C. sativa fungi, followed by a post-target screening of 283 pesticides based on a comprehensive spectral library. The validated procedure was applied to ten CBD-bas…
Occurrence and co-occurrence of Fusarium mycotoxins in wheat grains and wheat flour from Romania
2017
Abstract In this study, the presence of fourteen Fusarium mycotoxins, legislated by the European Union – deoxynivalenol, zearalenone, HT-2 and T-2 toxins (EC/1881/2006; 2013/165/EU), or non-legislated (five trichothecens and five “emerging” mycotoxins), was evaluated in 31 whole unprocessed wheat samples and 35 white wheat flour samples from different areas of Romania. For this purpose, a validated multi-mycotoxins liquid chromatography tandem mass spectrometry method was applied. Seventy three percent of the analyzed samples contained at least one mycotoxin. The highest occurrence was for enniatin B, 71% of the analyzed samples being positive (21–407 μg kg−1). Regarding the legislated myco…
Mitigation of enniatins in edible fish tissues by thermal processes and identification of degradation products.
2017
Emerging mycotoxins, such as enniatins and beauvericin, are common contaminants in vegetal matrices, but recently, the occurrence of mycotoxins in foodstuffs from animal origin has been also reported as they can be present in edible tissues of animals fed with contaminated feedstuffs. Sea bass, sea bream, Atlantic salmon and rainbow trout from aquaculture analyzed in the present survey showed contamination by emerging Fusarium mycotoxins enniatins (ENs). ENs were extracted from raw and cooked fish with acetonitrile and analyzed by Liquid Chromatography coupled to Mass Spectrometry. In this study, the stability of ENs was evaluated during food processing by the application of different cooki…
Occurrence, toxicity, bioaccessibility and mitigation strategies of beauvericin, a minor Fusarium mycotoxin.
2017
Emerging Fusarium mycotoxins include the toxic secondary metabolites fusaproliferin, enniatins, beauvericin (BEA), and moniliform. BEA is produced by some entomo- and phytopathogenic Fusarium species and occurs naturally on corn and corn-based foods and feeds infected by Fusarium spp. BEA has shown various biological activities (antibacterial, antifungal, and insecticidal) and possesses toxic activity, including the induction of apoptosis, increase cytoplasmic calcium concentration and lead to DNA fragmentation in mammalian cell lines. Cereals food processing has an important effect on mycotoxin stability, leading to less-contaminated food compared to the raw materials. Different industrial…
A study on the effect of contact pressure during physical activity on photoplethysmographic heart rate measurements
2020
Heart rate (HR) as an important physiological indicator could properly describe global subject&rsquo
Evaluation of sampling adsorbents and validation of a LC-HRMS method for determination of 28 airborne pesticides
2018
A new strategy for sampling, using a low-volume sampler, and determination of airborne pesticides by liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) has been developed. The trapping efficiency of three adsorbents (sandwich PUF-XAD2-PUF; XAD-2 and XAD-4) was tested for 33 currently used pesticides and the first adsorbent (PUF-XAD2-PUF) was selected because it presented the highest retention capacity without breakthrough. Selected PUF-XAD2-PUF had the following design: 5 g of Amberlite XAD-2 sandwiched between two cylinders of PUF (6.87 cm(3), height: 1.4 cm, diameter: 2.5 cm). A validation of the analytical methodology that includes microwave extraction with e…
Bomba rice conservation with a natural biofilm
2018
[EN] The chemical composition of commercial Syzygium aromaticum, Cinnamomum verum, and Laurus nobilis essential oils as well as their antifungal activity against four pathogenic fungi isolated from Mediterranean rice grains has been investigated. Eighty nine compounds accounting for between 98.5 and 99.4% of the total essential oil were identified. The phenylpropanoids eugenol (89.37 ± 0.29%) and eugenol (56.34 ± 0.41%), followed by eugenol acetate (19.48 ± 0.13%) were, respectively, the main compounds in clove and cinnamon essential oils, whereas large amounts of the oxygenated monoterpenes 1,8-cineole (58.07 ± 0.83%) and ¿-terpinyl acetate (13.05 ± 0.44%) were found in bay leaf essential …
Polyphenols, methylxanthines, fatty acids and minerals in cocoa beans and cocoa products
2019
In this study, the nutritional profile and some health benefit of three cocoa bean samples of different origins, including Perù, Ecuador (Criollo) and Ghana (Hybrid) and five samples of cocoa products from Criollo variety at different percentage of cocoa solids (from 70 to 100%), are investigated. The Ecuadorian beans were of the same batch used to obtain the chocolate samples (70% cocoa solids) by processing without conching. All samples were analyzed for their proximate composition, mineral content, fatty acids, total polyphenols, catechin, epicathechin theobromine and caffeine. Fatty acid profiles of the cocoa products were quite similar to those obtained in cocoa beans. The atherogenici…
Preparation of Highly Clarified Anthocyanin-Enriched Purple Sweet Potato Juices by Membrane Filtration and Optimization of Their Sensorial Properties
2016
The aim of this work was to prepare clarified anthocyanin-enriched juices from purple sweet potatoes (PSP) and to evaluate their sensorial properties, with promising prospect for antioxidant molecules. Four PSP juice samples were prepared and annotated as (1) crude PSP extract, (2) PSP extract followed by microfiltration, (3) by ultrafiltration and (4) by nanofiltration (4). Although anthocyanins retention was observed during the filtration process, PSP microfiltrated juices generated better permeate with compromising between appearance transparency and anthocyanin content. Juice sensory properties (color, flavor, mouthfeel and clarity) were optimized by an L9(34) orthogonal design using PS…