21 research outputs found
Determination of non-protein amino acids and betaines in vegetable oils by flow injection triple-quadrupole tandem mass spectrometry: a screening method for the detection of adulterations of olive oils.
This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Journal of Agricultural and Food Chemistry, copyright © American Chemical Society after peer review.A novel screening method using an automated flow injection electrospray ionization tandem mass spectrometry system is proposed for the simultaneous determination of five nonprotein amino acids (β-alanine, alloisoleucine, ornithine, citrulline, pyroglutamic acid) and three betaines (glycine betaine, trigonelline, proline betaine) after derivatization with butanolic HCl. MS/MS experiments were carried out in a triple-quadrupole instrument using multiple reaction monitoring mode in <2 min. The proposed method provided high fingerprinting power to identify the presence of five of the studied compounds in different types of vegetable oils (soybean, sunflower, corn, olive) with LODs at parts per billion levels. The method was validated, and different mixtures of extra virgin olive oil with seed oils were analyzed, achieving the typification for the detection of adulterations in extra virgin olive oils up to 2% w/w. The nonprotein amino acid ornithine was confirmed as a marker for adulteration in the olive oils analyzedThe projects involved in this work have been: project CTQ2009-09022 from the Spanish Ministry of Science and Innovation (Spain), project S2009/AGR-1464 from the Comunidad Autónoma of Madrid (Spain) and European funding from FEDER programme (ANALISYC-II), and project CCG10-UAH/AGR-5950 from the University of Alcalá and the Comunidad Autónoma of Madrid (Spai
Mineral and volatile composition of agua-mel from Portugal
Agua-mel (honey-water) is a typical honey-based product produced by the Portuguese beekeepers, particularly in southern Portugal. Agua-mel was characterized by mineral content and volatiles contents. Mineral content evaluation was performed based on a random sampling of 14 samples from a total of 16 samples provided by local producers. Mineral content showed that potassium predominated in agua-mel samples (1270-4105 mg/kg). The concentration of aluminium in one sample was tenfold higher (5.8 mg/kg) than in the remaining samples (0.3-0.6 mg/kg). Agua-mel volatiles were isolated by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) from a subset of eight samples. Cluster analysis showed two poorly correlated clusters (S (corr) < 0.3). Cluster I only sample was dominated by trans-beta-ocimene (19 %), gamma-terpinene (15 %) and 2-furfural (9 %). Cluster II that included the remaining seven samples showed two moderately correlated subclusters (S (corr) < 0.5). The six samples with high correlation from subcluster IIa were dominated by 2-furfural (18-41 %) and benzene acetaldehyde (12-39 %). n-Nonadecane (14 %), n-heneicosane and 2-furfural (both 13 %) were the main components of subcluster IIb sample. Although the presence of some volatile compounds can help in the correlation between agua-mel and honey botanical source, the final product varies largely according to the preparation process even for the same producer, in different years. Agua-mel detailed characterization may assist in bringing added value to this typical Portuguese honey-based product
Making Waves : Collaboration in the time of SARS-CoV-2-rapid development of an international co-operation and wastewater surveillance database to support public health decision-making
The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities. Within this context, the NORMAN SCORE "SARS-CoV-2 in sewage" database provides a platform for rapid, open access data sharing, validated by the uploading of 276 data sets from nine countries to-date. Through offering direct access to underpinning meta-data sets (and describing its use in data interpretation), the NORMAN SCORE database is a resource for the development of recommendations on minimum data requirements for wastewater pathogen surveillance. It is also a tool to engage public health practitioners in discussions on use of the approach, providing an opportunity to build mutual understanding of the demand and supply for data and facilitate the translation of this promising research application into public health practice. (C) 2021 Elsevier Ltd. All rights reserved.Peer reviewe
Making Waves:Collaboration in the time of SARS-CoV-2 - rapid development of an international co-operation and wastewater surveillance database to support public health decision-making
The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities. Within this context, the NORMAN SCORE “SARS-CoV-2 in sewage” database provides a platform for rapid, open access data sharing, validated by the uploading of 276 data sets from nine countries to-date. Through offering direct access to underpinning meta-data sets (and describing its use in data interpretation), the NORMAN SCORE database is a resource for the development of recommendations on minimum data requirements for wastewater pathogen surveillance. It is also a tool to engage public health practitioners in discussions on use of the approach, providing an opportunity to build mutual understanding of the demand and supply for data and facilitate the translation of this promising research application into public health practice.</p
Determinação simultânea de resíduos de cloranfenicol, tianfenicol e florfenicol em leite bovino por cromatografia eletrocinética micelar
A micellar electrokinetic chromatographic method (MEKC) is described for determining residues of amphenicols(chloramphenicol,thiamphenicol and florfenicol) in bovine milk. MEKC is conducted by using a separation buffer consisting of 20 mM Na2HPO4, 10 mM Na2B4O7, 50 mM SDS at pH 8.0; UV detection at 210 nm and 10 kV of voltage. The limit of detection ranged from 4.3-5.3 µg L-1. The MEKC method was applied for the simultaneous determination of amphenicols in milk samples spiked with amphenicols at three concentration levels: 10, 30 and 50 µg L-1. Recoveries ranging from 91-105% were obtained by following a simple extraction/preconcentration procedure
Determinação simultânea de resíduos de cloranfenicol, tianfenicol e florfenicol em leite bovino por cromatografia eletrocinética micelar
A micellar electrokinetic chromatographic method (MEKC) is described for determining residues of amphenicols(chloramphenicol,thiamphenicol and florfenicol) in bovine milk. MEKC is conducted by using a separation buffer consisting of 20 mM Na2HPO4, 10 mM Na2B4O7, 50 mM SDS at pH 8.0; UV detection at 210 nm and 10 kV of voltage. The limit of detection ranged from 4.3-5.3 µg L-1. The MEKC method was applied for the simultaneous determination of amphenicols in milk samples spiked with amphenicols at three concentration levels: 10, 30 and 50 µg L-1. Recoveries ranging from 91-105% were obtained by following a simple extraction/preconcentration procedure
Simultaneous determination of chloroamphenicl, thianphenicl and florfenicl residues in bovine milk by micellar electrokinetic chromatography
A micellar electrokinetic chromatographic
method (MEKC) is described for determining residues of amphenicols(chloramphenicol,thiamphenicol and florfenicol) in bovine
milk. MEKC is conducted by using a separation buffer consisting of 20 mM Na2HPO4, 10 mM Na2B4O7, 50 mM SDS at pH 8.0;
UV detection at 210 nm and 10 kV of voltage. The limit of detection ranged from 4.3-5.3 μg L-1. The MEKC method was
applied for the simultaneous determination of amphenicols in milk samples spiked with amphenicols at three concentration
levels: 10, 30 and 50 μg L-1. Recoveries ranging from 91-105% were obtained by following a simple extraction/preconcentration
procedure
Metabolomic fingerprinting of saffron by LC/MS: novel authenticity markers
An untargeted metabolomic approach using liquid chromatography coupled to electrospray ionization-time of flight-mass spectrometry was developed in this work to identify novel markers for saffron authenticity which is an important matter related to consumer protection, quality assurance, active properties, and also economical impact (saffron is the most expensive spice). Metabolic fingerprinting of authentic and suspicious saffron samples from different geographical origin was obtained and analysed. Different extracting protocols and chromatographic methodologies were evaluated to obtain the most adequate extracting and separation conditions. Using an ethanol/water mixture at pH 9.0 and an elution gradient with a fused core C18 column enabled obtaining the highest number of significant components between authentic and adulterated saffron. By using multivariate statistical analysis, predictive classification models for authenticity and geographical origin were obtained. Moreover, 84 and 29 significant metabolites were detected as candidates for markers of authenticity and geographical origin, respectively, from which only 34 metabolites were tentatively identified as authenticity markers of saffron, but none related to its geographical origin. Six characteristic compounds of saffron (kaempferol 3-O-glucoside, kaempferol 3-O-sophoroside, kaempferol 3,7-O-diglucoside, kaempferol 3,7,4´-O-triglucoside, kaempferol 3-O-sophoroside-7-O-glucoside, and geranyl-O-glucoside) were confirmed by comparing experimental MS/MS fragmentation patterns with those provided in scientific literature being proposed as novel markers of authenticity.Authors thank financial support from the Spanish Ministry of Science and Innovation (project CTQ2009-09022), the Comunidad of Madrid (Spain) and European funding from \ud
35 \ud
FEDER program (project S2013/ABI-3028, AVANSECAL-CM), and the University of Alcalá (project UAH2011/EXP-020). M. Guijarro-Díez thanks the Ministry of Science and Innovation for his predoctoral contract (BES-2010-033465). Authors also thank the kind gift of saffron samples by Carmencita Company and the group of Prof. Coral Barbas for the one month stay of M.G.D. in her laboratory to work with the different chemometric techniques used in this work
Microwave-Assisted Pyrolysis of Leather Waste
The processing of leather into leather is one of the oldest known manufacturing practices. The subsequent refinement of this technique over recent centuries has led to an increase in production, which in turn has led to an increase in waste production. Today, many of the by-products and waste streams from the leather industry have applications in industries such as petfood and in the production of collagen and derivatives, while others, such as waste from trimming and scraping the material, are disposed of in landfills, causing a detrimental environmental impact. For this reason, new alternatives for the treatment of these wastes, such as pyrolysis, are being investigated. The aim of this work is to assess the feasibility of recovering non-recyclable waste from the leather industry by pyrolysis. Waste from the tanning of cowhides with vegetable tannins and tanning with chrome salts, without pre-treatment, were used as raw materials. The operating conditions of the microwave-assisted pyrolysis were analysed by varying the time (15–30 min), the power (600–1000 W) and the dopant (carbon from the pyrolysis itself) in a batch reactor that allows to treat about 30 g of a sample. Three fractions (liquid, solid and gaseous) were obtained from the waste treatment, and the liquid and gaseous fractions were characterised using different analytical techniques. The solid fraction can be used as fuel due to its high calorific value of more than 20 MJ/kg and its low ash content, with the residue containing vegetable tannins giving the best results with a calorific value of up to 28 MJ kg−1. In addition, the solid fraction can be used as activated carbon after activation treatment, which allows for a more technical use, e.g., in the chemical industry. The liquid fraction contains significant amounts of phenolic groups, such as pyrrole and phenol, as well as other derivatives. Pyridine, aniline, cresol and succinimide, among others, were also found. This makes it a valid source of chemical compounds of high added value in the chemical industry. In addition, the heavy liquid fraction has a good heat capacity of more than 21 MJ/kg, which makes it suitable for use as a fuel. The microwave-assisted pyrolysis process results in the possibility of obtaining products from waste that would otherwise be destined for landfill, thereby obtaining a large number of products and bioproducts with the ability to be reintroduced into the value chain quickly and easily
Microwave-Assisted Pyrolysis of Leather Waste
The processing of leather into leather is one of the oldest known manufacturing practices. The subsequent refinement of this technique over recent centuries has led to an increase in production, which in turn has led to an increase in waste production. Today, many of the by-products and waste streams from the leather industry have applications in industries such as petfood and in the production of collagen and derivatives, while others, such as waste from trimming and scraping the material, are disposed of in landfills, causing a detrimental environmental impact. For this reason, new alternatives for the treatment of these wastes, such as pyrolysis, are being investigated. The aim of this work is to assess the feasibility of recovering non-recyclable waste from the leather industry by pyrolysis. Waste from the tanning of cowhides with vegetable tannins and tanning with chrome salts, without pre-treatment, were used as raw materials. The operating conditions of the microwave-assisted pyrolysis were analysed by varying the time (15–30 min), the power (600–1000 W) and the dopant (carbon from the pyrolysis itself) in a batch reactor that allows to treat about 30 g of a sample. Three fractions (liquid, solid and gaseous) were obtained from the waste treatment, and the liquid and gaseous fractions were characterised using different analytical techniques. The solid fraction can be used as fuel due to its high calorific value of more than 20 MJ/kg and its low ash content, with the residue containing vegetable tannins giving the best results with a calorific value of up to 28 MJ kg−1. In addition, the solid fraction can be used as activated carbon after activation treatment, which allows for a more technical use, e.g., in the chemical industry. The liquid fraction contains significant amounts of phenolic groups, such as pyrrole and phenol, as well as other derivatives. Pyridine, aniline, cresol and succinimide, among others, were also found. This makes it a valid source of chemical compounds of high added value in the chemical industry. In addition, the heavy liquid fraction has a good heat capacity of more than 21 MJ/kg, which makes it suitable for use as a fuel. The microwave-assisted pyrolysis process results in the possibility of obtaining products from waste that would otherwise be destined for landfill, thereby obtaining a large number of products and bioproducts with the ability to be reintroduced into the value chain quickly and easily