1,720,971 research outputs found
Sample preparation techniques coupled to advanced chromatographic methods for marine organisms investigation
No full textObjective: of this work was to develop suitable extraction methodologies for the isolation of lipids from fish, mussels and clams from the Mediterranean sea, and their successive analysis by means of advanced chromatographic instrumentation. More specifically, three different sample preparation methodologies were adopted: Folch's, Bligh & Dyer's and maceration. The lipidic extracts, after application of two different methylation procedures, were subjected to monodimensional and comprehensive two-dimensional GC analyses, in order to compare the fingerprints of samples derived from different extraction and transesterification methodologies. Triacylglycerols (TAGs) were analyzed by an off-line combination of silver-ion liquid chromatography with non-aqueous reversed phase liquid chromatography. In both LC and GC analyses, mass spectrometric detectors were used, which greatly supported the identification procedure. In particular, with respect to HPLC, mass spectrometry with atmospheric pressure chemical ionization in positive mode was applied
Developmentand Validation of SPE-based Protocol for the GC-MS Determination of FAMEs and FAEEs in EVOO
No full textAn in-depth study of the volatile variability of chinotto (Citrus myrtifolia Raf.) induced by the extraction procedure
No full textA variety of extraction methodologies were applied to chinotto (Citrus myrtifolia) fruits from Sicily, along with sensory and chemical analyses. By gas chromatographic techniques, either in monodimensional (GC-FID, GC–MS) or in multidimensional (MDGC) fashion, it was established how the isolation procedure affected the volatile fingerprint of such fruit. In general, limonene, linalyl acetate, myrcene, β-pinene, α-pinene, (E)-β-ocimene, linalool and geranyl acetate resulted to be the predominant volatiles. However, although revealed at lower levels, other compounds, such as trans-linalool oxide, perilla alcohol, trans-limonene oxide, may be responsible for peculiar olfactory notes. Compounds such as linalool, myrcene, β-pinene, octanal, decanal, and geranyl and perillyl acetates were selectively extracted by blending plus the addition of solvents. (E)-β-Ocimene and nootkatone were considerably expressed in hand-squeezed and solvent-extracted samples, respectively. On the other hand, linalyl acetate was the most abundant compound in samples extracted by solvent. Concerning the sensory evaluations, odor characters varied depending on the oil extraction methodology. Indeed, the flowery and citrus notes were perceived in all samples by the majority of panelists; conversely, the minty attribute was the one least smelled in five out of six samples. Enantio-MDGC analysis highlighted seven chiral pairs, with the following enantiomeric ratios: (−)/ (+) limonene (1.8/98.2), (−)/(+) linalyl acetate (99.4/0.6), (+)/(−) β-pinene (99.8/0.2), (−)/(+) linalool (5.5/94.5), (+)/(−) terpinen-4-ol (48.9/51.1), (−)/(+) α-pinene (22.3/77.7) and (−)/(+) α-terpineol (20.5/79.5)
15th Euro Fed Lipid Congress 27-30 August 2017- Uppsala- Swden " Oil, Fats and Lipids: New Technologies and Applications for a Healthier Life
No full textEffects of fasting and refeeding on the digestive tract of zebrafish (Danio rerio) fed with Spirulina (Arthrospira platensis), a high protein feed source
No full textIn the present work, morphological and molecular effects of short-term feed deprivation and refeeding with Spirulina (Arthrospira platensis) on zebrafish digestive tract were determined. Once elucidated the proximate composition of Spirulina feed, immunohistochemical and western blot analyses of peptide transporter (PepT1) and cholecystokinin (CCK8) were carried out in the gastrointestinal tract of zebrafish, previously morphologically investigated. Two and five fasting days caused not only morphostructural alterations, but also the downregulation of PepT1 and CCK8 proteins. Conversely,
the recovery of normal morphological conditions, along with an increased PepT1 and CCK8 expression, were observed after refeeding with Spirulina. The increase of PepT1 expression in zebrafish may be responsible for the enhanced CCK8 secretion, so that both proteins may contribute to an improved digestion process during refeeding.
These observations could be supported not only by compensatory mechanisms induced by fasting and refeeding but also by an higher protein quality of Spirulina-based diet
Effects of long-term exposure of Mytilus galloprovincialis to thiacloprid: A multibiomarker approach
No full textThiacloprid is a neonicotinoid insecticide widely exploited in agriculture and easily mobilized towards aquatic environments by atmospheric agents. However, little information about its toxicological effects on aquatic invertebrate bioindicators is available. In this study, specimens of the mussel Mytilus galloprovincialis were exposed to thiacloprid at environmental (4.5 μg L−1) and 100 times higher than environmental (450 μg L−1) concentrations for 20 days. Thiacloprid affected haemolymph biochemical parameters, cell viability in the digestive gland, antioxidant biomarkers and lipid peroxidation in the digestive gland and gills at environmentally relevant concentrations (4.5 μg L−1). In addition, thiacloprid exposure caused histological damage to the digestive gland and gills. Interestingly, the pesticide was detected at levels equal to 0.14 ng g−1 in the soft tissues of sentinels exposed for 20 days to 450 μg L−1 thiacloprid in seawaterμ. Due to its harmful potential and cumulative effects after long-term exposure of M. galloprovincialis, thiacloprid may pose a potential risk to nontarget aquatic organisms, as well as to human health. This aspect requires further in-depth investigation
Nano Liquid Chromatography Directly Coupled to Electron Ionization Mass Spectrometry for Free Fatty Acid Elucidation in Mussel
No full textRecently the miniaturization of liquid
chromatography (LC) systems
and progresses in mass spectrometry instrumentation have enabled direct
introduction of the effluent coming from a nanoLC column into the
high-vacuum region of an electron ionization source. In the present
research, a nanoLC system was directly coupled to an electron ionization
mass spectrometer (EI-MS) without any interface or modification of
the ion source. The advantage with respect to atmospheric pressure
ionization techniques, normally coupled with LC, is major identification
power because of a more extensive and reproducible fragmentation pattern,
without any matrix effect or mobile-phase interference. In particular,
a nanoLC/EI-MS method was developed for elucidation of the free fatty
acid profile in mussel samples, avoiding a previous derivatization
step, required when gas chromatographic analysis is involved. A total
of 20 fatty acids were reliably identified through the comparison
with commercial libraries. A quantitative determination was also carried
out by using the response factors approach along with the internal
standard method, allowing for quantification of 14 fatty acids. Among
them, palmitic acid resulted the most abundant, followed by ω6
arachidonic acid. The quantitative data were compared with those obtained
by a well-established technique, such as gas chromatography with flame
ionization detection (GC-FID). Both nanoLC/EI-MS and GC-FID methods
were validated and similar results were obtained in terms of limit
of detection and quantification, resulting in the picomole range,
and sensitivity as well was not significantly different, as demonstrated
by comparing the slope values of the calibration curves (p t-test)
Effect of Dietary Enrichment with Flaxseed, Vitamin E and Selenium, and of Market Class on the Broiler Breast Meat—Part 2: Technological and Sensorial Traits
Full text linkThe influence of diet enrichment with flaxseed, selenium and vitamin E, and market class on breast meat was investigated in terms of technological and sensorial quality of breast meat. A randomized complete block design with an experimental unit of n = 6000 broilers receiving a standard or enriched diet, and slaughtered at 37 (light class), 47 (medium class), or 57 (heavy class) days of life, was developed. Then, enriched and standard breast muscles from every market class were studied for their technological and sensorial traits—both at 24 h post-mortem and after one month of frozen storage—by a statistical multiple linear model. Redness and yellowness of muscles significantly (p < 0.05) increased and decreased with increasing market age. Moreover, the yellowness significantly (p < 0.05) raised after frozen storage. However, obtained data were always indicative of a normal meat color. The water holding capacity improved following fed enrichment and significantly (p < 0.05) worsened after frozen storage. For the sensory analysis, juiciness and chewing rest of meat resulted significantly (p < 0.05) improved with increasing slaughtering age and diet enrichment, as well as their mutual interaction, while they deteriorated after frozen storage. Overall, fresh and enriched muscles from heavy broilers had the best technological and sensorial traits, thus, confirming that market size and diet should be highly considered to obtain breast meat with greater consumer acceptance
Development of an antioxidant formula based on peanut by‐products and effects on sensory properties and aroma stability of fortified peanut snacks during storage
Full text linkAn antioxidant formula based on peanut skins and hulls, was developed and characterized for total and single polyphenols, and antioxidant power, considering the contribution provided by each peanut by‐product. Then, it was evaluated for its effect on sensory properties and aroma stability of peanut bars over a 100‐day period. To this purpose, snacks fortified and not with the natural additive were experimentally produced
Properties of a new food supplement containing actinia equina extract
Full text linkMarine species represent a great source of biologically active substances; Actinia equina (AE),
an Anthozoa Cnidaria belonging to the Actinidiae family, have been proposed as original food and have
already been included in several cooking recipes in local Mediterranean shores, and endowed with
excellent nutraceutical potential. The aim of this study was to investigate some unexplored features
of AE, through analytical screening and an in-vitro and in-vivo model. An in-vitro study, made on
RAW 264.7 stimulated with H2O2, showed that the pre-treatment with AE exerted an antioxidant
action, reducing lipid peroxidation and up-regulating antioxidant enzymes. On the other hand,
the in-vivo study over murine model demonstrated that the administration of AE extracts is able
to reduce the carrageenan (CAR)-induced paw edema. Furthermore, the histological damage due
to the neutrophil infiltration is prevented, and this highlights precious anti-inflammatory features
of the interesting food-stu. Moreover, it was assessed that AE extract modulated nuclear factor
kappa-light-chain-enhancer of activated B cells (NF-kB) and The nuclear factor erythroid 2–related
factor 2 (Nrf-2) pathways. In conclusion, our data demonstrated that thanks to the antioxidant and
anti-inflammatory properties, AE extract could be used as a new food supplement for inflammatory
pathology prevention
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