Modifications of plasma proteome in healthy humans fed o a coenzymen Q-10 supplemented diet

Comunicaciones a congreso

Chemical Biopreservative Effects of Red Seaweed on the Shelf Life of Black Tiger Shrimp (Penaeus monodon)

Hypnea musciformis (HM) and Acanthophora muscoides (AM) red seaweeds were evaluated for their antioxidant properties and efficacy to extend the chemical shelf life of black tiger shrimp (Penaeus monodon) during 14-daystorage. Treated shrimp were soaked in five percent ethanolic solution with 500 µg/mL of AM or HM powder for 30 min. HM had more phenols and flavonoids, increased radical scavenging activity, and greater H2O2 reducing power than AM in vitro. Biochemical quality indicators were significantly higher in the control group, followed by HM- and AM-treated samples during storage. On day 14 of storage, controls contained significantly higher amounts of biogenic amines than HM- or AM-treated samples. The shelf life of chilled stored shrimp increased due to the presence of compounds of butylated hydroxytoluene, sulfurous acid, heptadecane, mono (2-ethylhexyl), and 1,2-propanediol found in AM extract and sulfurous acid and 1,2-propanediol found in HM extract. A control group was soaked in the same ethanolic solution as treated samples without algae powder for 30 min. Each group was kept ice-cold during the soaking period. The results obtained demonstrate the usefulness of two seaweed extracts, Hypnea musciformis and Acanthophora muscoides, combined with ice by decreasing the formation of toxic biogenic amines in shrimp, enhancing its shelf life during ice storageThe authors thank the authorities of Alagappa University for providing necessary facilities to carry out the research work. The authors are grateful to Department of Science and Technology (DST)-Science and Engineering Research Board (SERB) New Delhi, Grant/Award Number: SR/FT/LS-22/2010; dt. 02.05.2012 for instrumentation facilities andEuropean Regional Development Funds (FEDER), grant ED431C 2018/05, for covering the cost of publicationS

Efecto de la cúrcuma (Curcuma longa) en la extensión de la vida útil y el control de aminas biógenas en sepia (Sepia brevimana) durante su almacenamiento refrigerado

Turmeric extract (0.5%) was applied to Sepia brevimana muscle to investigate its effects on muscle sensory evaluation, biochemical parameters, microbiological proliferation, and biogenic amine (BA) formation during storage at 4°C for 18 days. Sensory evaluation determined the shelf life of S. brevimana muscle to be 12 days for the controls and 15 days for the turmeric-treated samples. The biochemical quality index differences were significant in all instances, and the values were improved in the turmeric-treated samples compared to the control samples. Most microbiological counts were higher in the control samples than in the turmeric-treated samples after day 3. Additionally, the turmeric extract showed an inhibitory effect against some potential BA-forming bacteria. In conclusion, this study revealed the ability of turmeric extract to improve the shelf life and quality of S. brevimana muscle during chilled storage.Extracto de cúrcuma (0,5%) fue aplicado a músculo de Sepia brevimana con el fin de investigar sus efectos sobre la calidad sensorial, parámetros bioquímicos, calidad microbiológica, y la formación de aminas biogénicas durante 18 días de almacenamiento a 4°C. La evaluación sensorial determinó que la vida útil del músculo de S. brevimana alcanzó 12 días en el caso de los controles y 15 días para las muestras tratadas. Los parámetros relativos a la calidad bioquímica, fueron significativamente mejores en todos los casos en las muestras tratadas. La mayor parte de los parámetros microbiológicos mostraron mayores recuentos en las muestras controles en comparación con las muestras tratadas después del día 3. Además, el extracto de cúrcuma mostró un efecto inhibidor frente al desarrollo de bacterias potencialmente productoras de aminas biógenas. En conclusión, este estudio demostró que el extracto de cúrcuma mejora la vida útil y la calidad del músculo de S. brevimana durante el almacenamiento refrigerado.The authors gratefully acknowledge the Department of Science and Technology (DST), Science and Engineering Research Board (SERB) (Government of India, New Delhi) for their financial support [grant no. SR/FT/LS-22/2010; 2 May 2012] and to European Regional Development Funds (FEDER), grant GRC 2014/004 for covering the costs to publish in open accessS

Desarrollo de un método abreviado para la determinación cuantitativa de ácidos grasos en leche con especial énfasis en los ácidos grasos de cadena larga

A new and simple method was developed for the extraction and derivatization of fatty acid (FA) in milk. Lipid extraction of milk was carried out in H2SO4/methanol. Methylation was performed for 2 h at 60°C, and FA methyl esters were recovered for chromatographic analysis by the addition of hexane. The method parameters were optimized and the simple method was compared to the official reference procedure for the extraction and methylation of FAs in milk samples. For most of the 24 FAs determined, similar or significantly higher recoveries were obtained by the simple method than by the conventional method. The simple method allows processing a high number of samples, at the same time, minimizing the sample manipulation and, consequently, the sample loss and contamination. In conclusion, the proposed method is simple, rapid, low cost, and achieves good resultsUn nuevo método abreviado se desarrolló para la extracción y derivatización de ácidos grasos en leche. La extracción de los lípidos de la leche se llevó a cabo en H2SO4/metanol. La metilación se realizó a 60°C durante 2 h y los ésteres metílicos de los ácidos grasos fueron recuperados para el análisis cromatográfico mediante la adición de hexano. Los parámetros del método fueron optimizados y el método abreviado fue comparado con el método de referencia para la determinación de ácidos grasos en leche. En la mayor parte de los 24 ácidos grasos analizados, el método abreviado mostró recuperaciones similares o mejores que el método convencional. El método simple permite procesar un alto número de muestras al mismo tiempo, minimizando la manipulación de la muestra y consecuentemente la pérdida de la misma y su contaminación. En conclusión, el método propuesto es simple, rápido, económico y logra buenos resultadosThe authors thank Consellería do Medio Rural (FEADER 2008/32 and FEADER 2008/33) and Dirección Xeral de Investigación Desenvolvemento e Innovación (Xunta de Galicia, Lucas Labrada program) for financial supportS

Magnetic molecularly imprinted stirring bar for isolation of patulin using grafting technique

The 19th International Electronic Conference on Synthetic Organic Chemistry session Polymer and Supramolecular ChemistryMycotoxins are low-molecular-weight natural products with great structural diversity produced as secondary metabolites by fungi. One of the principal toxic fungal metabolites is patulin (PAT), produced by over 30 genera of mold including species as Penicillium expansum or Penicillium griseofulvum, and normally related to vegetable-based products and fruit, mainly apple. These mold grow easily in damaged fruit or in derived-product as juices if storage conditions are deficient. Some of the most serious effects of PAT ingestion are agitation, convulsions, edema, ulceration intestinal, inflammation and vomiting. Thus, European Regulation 1881/2006 established a maximum content of 10 ppb in infant fruit juices, 50 ppb for fruit juices in adults and 25 ppb in fruit-derived products. Nowadays, the official analytical method for food adopted by AOAC International is HPLC with UV detection, using clean-up with ethyl acetate and sodium carbonate. However, the diverse drawbacks of this method (poor stability of PAT under alkaline extraction, poor resolution between PAT and co-extracted hydroxymethylfurfural) have originated interest in alternative options, such as LC methods coupled to mass spectrometry. In the last years, purification with molecularly imprinted polymers (MIP) started to be used, and are becoming promising materials for extracting different analytes present in food. Mycotoxins are too toxic or too expensive to be used as template molecules in MIP preparation. Template “bleeding” may be an additional problem, especially when dealing with very low detection levels. In the present work, a rapid and selective method based on magnetic molecularly imprinted stir-bar (MMIB) extraction has been developed for the isolation of PAT. A structural analogue, 2-oxindole, was used as dummy template. The polymer was grafted to the silanized glass surface of the stir ba

Development of a novel molecularly imprinted stir-bar for isolation of aflatoxins

The 19th International Electronic Conference on Synthetic Organic Chemistry session Polymer and Supramolecular ChemistryMycotoxins are natural substances produced as secondary metabolites by a wide variety of different species of filamentous fungi. One of the most important groups in terms of occurrence and toxicity, is the group of aflatoxins (AFs). The major members of this group are aflatoxin B1, B2, G1, G2, M1 and M2. Exposure to AFs can cause chronic and acute toxic effects or death, as they can be carcinogenic, mutagenic, teratogenic and immunosuppressive. AFB1 is considered as the strongest carcinogen of natural origin and it is normally predominant in crops as well as in food products. Aflatoxin M1 is a major metabolite of aflatoxin B1 in humans and animals and it may be present in milk from animals fed with contaminated feed. Although the toxicity of M1 is about ten times lower than B1, it is known for its hepatotoxic and carcinogenic effects. Solid phase extraction (SPE) or the clean-up with organic solvents or immunoaffinity columns (IAC) have been frequently applied in the analysis of mycotoxins from cereals and/or milk. IAC in combination with HPLC are increasingly used as reference method due to their high selectivity and good elimination of matrix interferences. However, the cost of analysis is usually high. In recent years, molecularly imprinted polymers (MIP) have been become very popular and promising materials for extracting different analytes. AFs are too toxic to be used in MIP preparation and template bleeding may be an additional problem, especially when dealing with very low levels. For this reason, a dummy template was preferred for MIP synthesis. A rapid and selective extraction method based on magnetic MIP (MMIP) has been developed for the isolation of aflatoxins (B1, B2, G1, G2, M1) using a combination of imprinted polymer and magnetite. The successful MMIP stirring “cake” (used as a stir-bar) has been combined with HPLC-MS/MS for the determination of AFM1 in milk powder (infant formulas) to demonstrate its applicability to real sample

Ternary Quantum Dots in Chemical Analysis. Synthesis and Detection Mechanisms

Ternary quantum dots (QDs) are novel nanomaterials that can be used in chemical analysis due their unique physicochemical and spectroscopic properties. These properties are size-dependent and can be adjusted in the synthetic protocol modifying the reaction medium, time, source of heat, and the ligand used for stabilization. In the last decade, several spectroscopic methods have been developed for the analysis of organic and inorganic analytes in biological, drug, environmental, and food samples, in which different sensing schemes have been applied using ternary quantum dots. This review addresses the different synthetic approaches of ternary quantum dots, the sensing mechanisms involved in the analyte detection, and the predominant areas in which these nanomaterials are usedThe authors give thanks to the CONACYT support for the grant number 771019S

Preservative Effect of Aqueous and Ethanolic Extracts of the Macroalga Bifurcaria bifurcata on the Quality of Chilled Hake (Merluccius merluccius)

This work addressed the preservative behaviour of different icing media containing extracts from the alga Bifurcaria bifurcata. A comparative study of the antimicrobial and antioxidant effects of aqueous and ethanolic extracts of this macroalga was carried out. Whole hake (Merluccius merluccius) pieces were stored in ice containing either kind of extract and analysed for quality changes throughout a 13-day storage period. A progressive loss of microbial and biochemical quality was detected in all batches as chilling time increased. A significant inhibitory effect (p < 0.05) on microbial activity could be observed as a result of including the aqueous (lowering of psychrotrophic and lipolytic counts and pH value) and ethanolic (lowering of psychrotrophic and lipolytic counts) extracts. Additionally, both kinds of extract led to a substantial inhibition (p < 0.05) in the lipid hydrolysis rate (formation of free fatty acids), greater in the case of the batch containing ethanolic extract. Concerning lipid oxidation, a similar inhibitory effect (p < 0.05) on the formation of secondary compounds (thiobarbituric acid substances) was noticed in fish specimens corresponding to both alga extracts; however, more (p < 0.05) peroxide formation was detected in fish corresponding to the ethanolic extract batch. A preservative effect can be concluded for both kinds of extract; this effect agrees with previous studies reporting the presence of hydrophilic and lipophilic bioactive compounds in B. bifurcataThis research was funded by CONSEJO SUPERIOR DE INVESTIGACIONES CIENTÍFICAS (CSIC, Spain), GRANT NUMBER 2013-70E001S

Impedimetric Biosensor Based on a Hechtia argentea Lectin for the Detection of Salmonella spp.

A sensitive electrochemical detection method for Salmonella spp. was described, based on the use of Hechtia argentea lectin immobilised on a screen-printed gold electrode. The lectin was extracted from Hechtia argentea, a plant belonging to the Bromeliaceae family. The lectin with molecular weight near 27.4 kDa showed selectivity towards D-mannose, contained on the lipopolysaccharide cell wall of Salmonella spp. Carbohydrate selectivity of the lectin was measured as a change in impedance with respect to concentration. The binding of the bacteria to the biosensor surface increased impedance with increasing concentrations of Salmonella spp., achieving a linear range of detection of 15–2.57 × 107 CFU mL−1, with a limit of detection of 5 CFU mL−1. Increases in impedance were measured using electrochemical impedance spectroscopy and analysed using Nyquist plots. The biosensor was applied in analysis of hen egg samples, and the results were consistent with those obtained using the official analysis methodologyS