Despite the prohibition of the importation, production, distribution, marketing and use of geneti... more Despite the prohibition of the importation, production, distribution, marketing and use of genetically modified (GM) plants in Algeria, no legislation regarding their use in food and feed production has been established. The present work describes, for the first time, a full-stage study to monitor genetically modified organisms (GMO) in Algeria, based on a comprehensive survey of maize-derived foods, providing screening, event-specific identification and quantitative data targeting 11 maize events (Bt176,
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Authenticity evaluation in meat products encompasses many issues, including the fraudulent substi... more Authenticity evaluation in meat products encompasses many issues, including the fraudulent substitution of higher commercial valued meats by cheaper meats and the presence of undeclared species. Due to its characteristic and intensive flavour and its healthier composition, game meats are considered as delicacy products and command higher prices compared to other meats, thus being susceptible targets for frauds. The manufacture of traditional meat products is a long-established practice in the Northeast of Portugal, being "Aiheiras" one of the most appreciated products. "Aiheiras"are traditional smoked fermented sausages,mainly produced with pork and poultry meat in a mixture with bread and spices. Currently, game meat "Aiheiras" are also available as very attractive meat productsand prone to adulterations. To allow accurate information for consumers and avoid unfair competition among producers, it is important to develop efficient methodologiesto assess meat speciesidentification and verify the compliance with labelling. This work aimed to develop analytical tools to assess authenticity of game meat "Aiheiras", contributing to their valorisation. For this purpose, polymerase chain reaction (PCR) was the technique of choice for its specificity, fastness, accuracy and sensitivity. Meat species under study were game bird meat (partridge, pheasant and wild duck), chicken andturkey. Reference meat mixtures containing known amounts of each meat were prepared. DNA was extracted using the Wizard method. To specifically detect partridge (A/ectoris spp.) and pheasant (Phasianus co/chinus) species, specific primers targeting the mitochondrial 12S rRNA gene were used to obtain 141 bp and 113 bp DNA fragments (Rojas et al. , 2009). To detect turkey (Meleagris gallopavo), chicken (Gal/us gal/us) and duck (Anas platyrhynchos), specific primers were designed targeting the cytb gene to amplify 144 bp, 129 bp and 111 bp fragments, respectively. The results showed the specific PCR detection forall species until the level of 0.01 %addition in pork meat, except for turkey (0.1%). The proposed techniques were successfully applied to 15 commercial samples of game meat "Aiheiras". Partridge meat was detected in one out of 5 samples, while pheasant was not detected in none of the 2 samples labelled as containing partridge and pheasant, respectively. Among 7 samples declaring duck meat, its detection was verified only in 4. In opposition to these results, the detection of chicken was obtained in 13 samples, from which only 3 had this indication on the label, and turkey, which was declared in only one sample, was identified in 5 "Aiheiras". These preliminary results suggest clearly the omission of the game meat species under study and the predominant presence of undeclared chicken and turkey for its replacement. The conclusions seem to indicate the misleading labelling of game meat "Aiheiras" and the need to valorise and protect this kind of traditional products.
Do NOT write outside the grey boxes. Any text or images outside the boxes will be deleted. Do NOT... more Do NOT write outside the grey boxes. Any text or images outside the boxes will be deleted. Do NOT alter the structure of this form. Simply enter your information into the boxes. The form will be automatically processedif you alter its structure your submission will not be processed correctly. Do not include keywordsyou can add them when you submit the abstract online.
In the last years, the increase in the cultivated area of genetically modified (GM) maize has bec... more In the last years, the increase in the cultivated area of genetically modified (GM) maize has become a reality. GA2I, MON810 and MON863 maize crops are Some of the authorized maize events for food and feed under the European Union (EU) regulations. These crops of transgenic maize bring profit towards the conventional ones, as they confer resistance to some plagues and/or herbicides [1]. Concerning the raise of production and consumption of foodstuffs derived from genetically modified organisms (GMO), the EU has established new demand levels, including the labeling requirements when the product has GMO in a proportion higher than 0.9% (Regulation (BC) N .• 1829/2003).
The introduction of genes isolated from different Bacillus thuringiensis strains to express Cry-t... more The introduction of genes isolated from different Bacillus thuringiensis strains to express Cry-type toxins in transgenic crops is a common strategy to confer insect resistance traits. This work intended to extensively in silico analyse Cry1A(b)16 protein for the identification of peptide markers for the biorecognition of transgenic crops. By combining two different strategies based on several bioinformatic tools for linear epitope prediction, a set of seven peptides was successfully selected as potential Cry1A(b)16 immunogens. For the prediction of conformational epitopes, Cry1A(b)16 models were built on the basis of three independent templates of homologue proteins of Cry1A(a) and Cry1A(c) using an integrated approach. PcH_736-746 and PcH_876-886 peptides were selected as the best candidates, being synthesised and used for the production of polyclonal antibodies. To the best of our knowledge, this is the first attempt of selecting and defining linear peptides as immunogenic markers of Cry1A(b)type toxins in transgenic maize.
(Your abstract must use Normal style and must fit in this box. Your abstract should be no longer ... more (Your abstract must use Normal style and must fit in this box. Your abstract should be no longer than 300 words. The box will ‘expand’ over 2 pages as you add text/diagrams into it.) Soybean is the most important genetically modified crop in the world, comprising almost 60% of the biotechnological planted area. The doubts raised by the use of genetically modified organisms (GMO) lead to the compulsory labelling for food products containing more than 0.9% of authorised GMO in the EU. The analysis of DNA coupled with polymerase chain reaction (PCR) has been the technique of choice to monitor the presence of GMO in food. Since the approval of Roundup Ready soybean in Europe, the production of soybean oil using GM seeds has been increasing. Although several reports show the possibility of detecting DNA in crude vegetable oils, due to the chemical treatments and high temperatures used along refining, detection of DNA in refined oils is very difficult to accomplish. In this work, four methods, namely CTAB, Wizard, Nucleospin ® food kit for food and the Wizard ® Magnetic DNA purification system for food, were tested for soybean DNA extraction in commercial vegetables oils, based on previous work testing several soybean food matrices [1]. The DNA extracts were evaluated for their amplifiability by PCR targeting the lectin gene as a marker for soybean. The results showed that the Wizard ® Magnetic kit did not allow the detection of amplifiable DNA. Negative results were also obtained using the Wizard method after the pre-concentration by centrifuging 200 g of refined oil. The CTAB method using the same pre-concentrated step allowed the detection of DNA traces in some of the samples tested. The same amount of oil extracted with the Nucleospin ® kit, allowed the extraction of amplifiable soybean DNA from all tested samples labelled as containing soybean oil. This result showed that the Nucleospin food kit can be successfully used for DNA extraction from refined oils, enabling the detection of GMO in these products. [1] Mafra, I; Silva, S. A.; Moreira, E. J. M. O.; Silva, C. S. F.; Oliveira, M. B. P. P.; (2008). Comparative study of DNA extraction methods for soybean derived food products, Food Control, 19:1183-1190.
As reações alérgicas causadas pela ingestão de alimentos constituem um problema emergente na gest... more As reações alérgicas causadas pela ingestão de alimentos constituem um problema emergente na gestão da segurança alimentar. De modo fi salvaguardar a saúde dos consumidores, os ingredientes que possam causar reações alérgicas devem ser devidamente rotulados c a contaminação cruzada deve ser evitada. Entre as diversas reações provocadas pelos alimentos que contêm produtos de casca rija (chocolate, bolachas e bolos), as provocadas pelos alimentos que contêm avelã são consideradas das mais perigosas devido à sua frequência e gravidade [1]. Recentemente, a detecção de resíduos de alergénios recorrendo a técnicas baseadas no DNA, em particular, na reação em cadeia da polimerase (PCR) têm-se mostrado alternativas promissoras aos métodos imunológicos correntes. Contudo, matrizes complexas como o chocolate, contêm polissacarídeos e polifenóis que inibem a PCR. Actualmente existem diversos kits comerciais que peemitem a extração de DNA, mas apenas um número limitado permite a obtenção de DNA em quantidade e pureza adequadas para PCR. Pretendeu-se com este trabalho comparar diversos métodos de extracção de DNA (CTAB, Wizard, Nucleospin e Wizard Magnetic) com e sem a adição de polivinilpirrolidona (PVP) c/ou RNAse. Para tal, prepararam-se misturas de referência contendo quantidades conhecidas de avelã em chocolate (0.01-10%) e procedeu-se à extracção. O rendimento e pureza dos extratos foram avaliados por espectrofotometria. Para a detecção de avelã foram usados primers específicos para o gene hspl para a obtenção de fragmentos de 100 bp [2]
Despite the prohibition of the importation, production, distribution, marketing and use of geneti... more Despite the prohibition of the importation, production, distribution, marketing and use of genetically modified (GM) plants in Algeria, no legislation regarding their use in food and feed production has been established. The present work describes, for the first time, a full-stage study to monitor genetically modified organisms (GMO) in Algeria, based on a comprehensive survey of maize-derived foods, providing screening, event-specific identification and quantitative data targeting 11 maize events (Bt176,
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Authenticity evaluation in meat products encompasses many issues, including the fraudulent substi... more Authenticity evaluation in meat products encompasses many issues, including the fraudulent substitution of higher commercial valued meats by cheaper meats and the presence of undeclared species. Due to its characteristic and intensive flavour and its healthier composition, game meats are considered as delicacy products and command higher prices compared to other meats, thus being susceptible targets for frauds. The manufacture of traditional meat products is a long-established practice in the Northeast of Portugal, being "Aiheiras" one of the most appreciated products. "Aiheiras"are traditional smoked fermented sausages,mainly produced with pork and poultry meat in a mixture with bread and spices. Currently, game meat "Aiheiras" are also available as very attractive meat productsand prone to adulterations. To allow accurate information for consumers and avoid unfair competition among producers, it is important to develop efficient methodologiesto assess meat speciesidentification and verify the compliance with labelling. This work aimed to develop analytical tools to assess authenticity of game meat "Aiheiras", contributing to their valorisation. For this purpose, polymerase chain reaction (PCR) was the technique of choice for its specificity, fastness, accuracy and sensitivity. Meat species under study were game bird meat (partridge, pheasant and wild duck), chicken andturkey. Reference meat mixtures containing known amounts of each meat were prepared. DNA was extracted using the Wizard method. To specifically detect partridge (A/ectoris spp.) and pheasant (Phasianus co/chinus) species, specific primers targeting the mitochondrial 12S rRNA gene were used to obtain 141 bp and 113 bp DNA fragments (Rojas et al. , 2009). To detect turkey (Meleagris gallopavo), chicken (Gal/us gal/us) and duck (Anas platyrhynchos), specific primers were designed targeting the cytb gene to amplify 144 bp, 129 bp and 111 bp fragments, respectively. The results showed the specific PCR detection forall species until the level of 0.01 %addition in pork meat, except for turkey (0.1%). The proposed techniques were successfully applied to 15 commercial samples of game meat "Aiheiras". Partridge meat was detected in one out of 5 samples, while pheasant was not detected in none of the 2 samples labelled as containing partridge and pheasant, respectively. Among 7 samples declaring duck meat, its detection was verified only in 4. In opposition to these results, the detection of chicken was obtained in 13 samples, from which only 3 had this indication on the label, and turkey, which was declared in only one sample, was identified in 5 "Aiheiras". These preliminary results suggest clearly the omission of the game meat species under study and the predominant presence of undeclared chicken and turkey for its replacement. The conclusions seem to indicate the misleading labelling of game meat "Aiheiras" and the need to valorise and protect this kind of traditional products.
Do NOT write outside the grey boxes. Any text or images outside the boxes will be deleted. Do NOT... more Do NOT write outside the grey boxes. Any text or images outside the boxes will be deleted. Do NOT alter the structure of this form. Simply enter your information into the boxes. The form will be automatically processedif you alter its structure your submission will not be processed correctly. Do not include keywordsyou can add them when you submit the abstract online.
In the last years, the increase in the cultivated area of genetically modified (GM) maize has bec... more In the last years, the increase in the cultivated area of genetically modified (GM) maize has become a reality. GA2I, MON810 and MON863 maize crops are Some of the authorized maize events for food and feed under the European Union (EU) regulations. These crops of transgenic maize bring profit towards the conventional ones, as they confer resistance to some plagues and/or herbicides [1]. Concerning the raise of production and consumption of foodstuffs derived from genetically modified organisms (GMO), the EU has established new demand levels, including the labeling requirements when the product has GMO in a proportion higher than 0.9% (Regulation (BC) N .• 1829/2003).
The introduction of genes isolated from different Bacillus thuringiensis strains to express Cry-t... more The introduction of genes isolated from different Bacillus thuringiensis strains to express Cry-type toxins in transgenic crops is a common strategy to confer insect resistance traits. This work intended to extensively in silico analyse Cry1A(b)16 protein for the identification of peptide markers for the biorecognition of transgenic crops. By combining two different strategies based on several bioinformatic tools for linear epitope prediction, a set of seven peptides was successfully selected as potential Cry1A(b)16 immunogens. For the prediction of conformational epitopes, Cry1A(b)16 models were built on the basis of three independent templates of homologue proteins of Cry1A(a) and Cry1A(c) using an integrated approach. PcH_736-746 and PcH_876-886 peptides were selected as the best candidates, being synthesised and used for the production of polyclonal antibodies. To the best of our knowledge, this is the first attempt of selecting and defining linear peptides as immunogenic markers of Cry1A(b)type toxins in transgenic maize.
(Your abstract must use Normal style and must fit in this box. Your abstract should be no longer ... more (Your abstract must use Normal style and must fit in this box. Your abstract should be no longer than 300 words. The box will ‘expand’ over 2 pages as you add text/diagrams into it.) Soybean is the most important genetically modified crop in the world, comprising almost 60% of the biotechnological planted area. The doubts raised by the use of genetically modified organisms (GMO) lead to the compulsory labelling for food products containing more than 0.9% of authorised GMO in the EU. The analysis of DNA coupled with polymerase chain reaction (PCR) has been the technique of choice to monitor the presence of GMO in food. Since the approval of Roundup Ready soybean in Europe, the production of soybean oil using GM seeds has been increasing. Although several reports show the possibility of detecting DNA in crude vegetable oils, due to the chemical treatments and high temperatures used along refining, detection of DNA in refined oils is very difficult to accomplish. In this work, four methods, namely CTAB, Wizard, Nucleospin ® food kit for food and the Wizard ® Magnetic DNA purification system for food, were tested for soybean DNA extraction in commercial vegetables oils, based on previous work testing several soybean food matrices [1]. The DNA extracts were evaluated for their amplifiability by PCR targeting the lectin gene as a marker for soybean. The results showed that the Wizard ® Magnetic kit did not allow the detection of amplifiable DNA. Negative results were also obtained using the Wizard method after the pre-concentration by centrifuging 200 g of refined oil. The CTAB method using the same pre-concentrated step allowed the detection of DNA traces in some of the samples tested. The same amount of oil extracted with the Nucleospin ® kit, allowed the extraction of amplifiable soybean DNA from all tested samples labelled as containing soybean oil. This result showed that the Nucleospin food kit can be successfully used for DNA extraction from refined oils, enabling the detection of GMO in these products. [1] Mafra, I; Silva, S. A.; Moreira, E. J. M. O.; Silva, C. S. F.; Oliveira, M. B. P. P.; (2008). Comparative study of DNA extraction methods for soybean derived food products, Food Control, 19:1183-1190.
As reações alérgicas causadas pela ingestão de alimentos constituem um problema emergente na gest... more As reações alérgicas causadas pela ingestão de alimentos constituem um problema emergente na gestão da segurança alimentar. De modo fi salvaguardar a saúde dos consumidores, os ingredientes que possam causar reações alérgicas devem ser devidamente rotulados c a contaminação cruzada deve ser evitada. Entre as diversas reações provocadas pelos alimentos que contêm produtos de casca rija (chocolate, bolachas e bolos), as provocadas pelos alimentos que contêm avelã são consideradas das mais perigosas devido à sua frequência e gravidade [1]. Recentemente, a detecção de resíduos de alergénios recorrendo a técnicas baseadas no DNA, em particular, na reação em cadeia da polimerase (PCR) têm-se mostrado alternativas promissoras aos métodos imunológicos correntes. Contudo, matrizes complexas como o chocolate, contêm polissacarídeos e polifenóis que inibem a PCR. Actualmente existem diversos kits comerciais que peemitem a extração de DNA, mas apenas um número limitado permite a obtenção de DNA em quantidade e pureza adequadas para PCR. Pretendeu-se com este trabalho comparar diversos métodos de extracção de DNA (CTAB, Wizard, Nucleospin e Wizard Magnetic) com e sem a adição de polivinilpirrolidona (PVP) c/ou RNAse. Para tal, prepararam-se misturas de referência contendo quantidades conhecidas de avelã em chocolate (0.01-10%) e procedeu-se à extracção. O rendimento e pureza dos extratos foram avaliados por espectrofotometria. Para a detecção de avelã foram usados primers específicos para o gene hspl para a obtenção de fragmentos de 100 bp [2]
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