Browsing by Author "Herrero, Baudilio"
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- Antioxidant activity of twenty wild Spanish Thymus mastichina L. populations and its relation with their chemical compositionPublication . Delgado, Teresa; Marinero, Pilar; Asensio-S.-Manzanera, M. Carmen; Asensio, Carmen; Herrero, Baudilio; Pereira, J.A.; Ramalhosa, ElsaThe antioxidant activity and chemical composition of essential oils and methanolic extracts of twenty Spanish Thymus mastichina L. populations were studied. Both essential oils and methanolic extracts possessed antioxidant properties. However, the total phenol contents of the methanolic extracts varied between 2.90 and 9.15mg GAE/g extract and the EC 25 values of DPPH free radical scavenging activity between 0.90 and 3.45mg/mL for the methanolic extracts and 78-241mg/mL for essential oils, these showing low antioxidant potential. Actually, in essential oils the main compound determined was the 1,8-cineole (56.8-69.6%), whereas thymol, γ-terpinene, terpinolene and geraniol (species with considerable DPPH scavenging activity) were observed in low amounts. Concerning methanolic extracts, rosmarinic acid was the most abundant polyphenol (1.70-9.85mg/g), followed by methoxysalicylic acid, apigenin, kaempferol and luteolin.
- By-product of Lavandula latifolia essential oil distillation as source of antioxidantsPublication . Méndez-Tovar, Inés; Herrero, Baudilio; Pérez-Magariño, Silvia; Pereira, J.A.; Asensio-S.-Manzanera, M. CarmenThe objective of this work was to evaluate the antioxidant properties of Lavandula latifolia waste obtained after essential oil distillation. Samples of 12 wild populations of the Lavandula genus collected between 2009 and 2010 were hydrodistilled and their by-products were analyzed using the FolineCiocalteu, free radical scavenging activity (2,2-diphenyl-1- picrylhydrazyl), and the ferric reducing antioxidant power (FRAP) methods. Rosmarinic acid, apigenin, and luteolin contents were analyzed by high-performance liquid chromatographyediode array detection. The mean of total phenolic content ranged from 1.89 ± 0.09 mg gallic acid equivalents/g dry weight to 3.54 ± 0.22 mg gallic acid equivalents/ g dry weight. The average value of the half maximal effective concentration (EC50) for scavenging activity ranged from 5.09 ± 0.17 mg/mL to 14.30 ± 1.90 mg/mL and the variability of the EC50 in FRAP ranged from 3.72 ± 0.12 mg/mL to 18.55 ± 0.77 mg/mL. Annual variation was found among this samples and the environmental conditions of 2009 were found to be more favorable. The plants collected from Sedano showed the highest antioxidant power. Our results show that rosmarinic acid and apigenin in L. latifolia contributed to the antioxidant properties of the waste. In conclusion, the by-product of the distillation industry could be valorizing as a source of natural antioxidants.
- Identification of the geographical origin of Spanish beech nuts, Fagus sylvatica L., using a chemometric supervised approachPublication . Lamas, Sandra; Rodrigues, Nuno; Herrero, Baudilio; Casal, Susana; Cruz, Rebeca; Pereira, José Alberto; Peres, António M.In general, dry nuts, such as hazelnuts, almonds. chestnuts and walnuts, composition has been investigated and are well characterized. Nevertheless, other less unknown nuts, such as beech nuts have little information. Beech nuts proceed from the Fagus sylvatica L. tree, which is prevalent in central and southem Europe, and is commonly used for oil extraction. A study carried out by Obranovic et al. found that the chemical composition of beech nut oit varies significantly depending on the geographical origin. Siger et al. characterized the oit obtained from beech nut seeds, highlighting its high content in linoleic acid. However, scientific data regarding the physicochemical properties and composiHon of beech nuts are scarce. In this context. this work evaluated whether there are differences in terms of the physicochemical data and composition of the beech nut between regions, by applying a chemometric procedure.
- Identification of the geographical origin of Spanish beech nuts, Fagus sylvatica L., using a chemometric supervised approachPublication . Lamas, Sandra; Rodrigues, Nuno; Herrero, Baudilio; Casal, Susana; Cruz, Rebeca; Pereira, José Alberto; Peres, António M.In general, dry nuts, such as hazelnuts, almonds, chestnuts and walnuts, composition has been investigated and are well characterized. Nevertheless, other less unknown nuts, such as beech nuts have little information. Beech nuts proceed from the Fagus sylvatica L. tree, which is prevalent in central and southern Europe, and is commonly used for oil extraction. A study carried out by Obranovic et al.1 found that the chemical composition of beech nut oil varies significantly depending on the geographical origin. Siger et al.2 characterized the oil obtained from beech nut seeds, highlighting its high content in linoleic acid. However, scientific data regarding the physicochemical properties and composition of beech nuts are scarce. In this context, this work evaluated whether there are differences in terms of the physicochemical data and composition of the beech nut between regions, by applying a chemometric procedure. Seeds were collected from three different regions in Spain, namely Burgos, León and Palencia. Moisture analysis was performed on the seeds from each region, followed by oil extraction. The extracted oil was subsequently analyzed to determine the total phenolic content, antioxidant activity (using reducing power, ABTS, and DPPH assays), tocopherols composition (including α-, β-, and γ-tocopherol), and fatty acid profiles. A linear discriminant analysis (LDA) was performed, establishing a multivariate classification model based on six variables selected as the most informative predictors, by the simulated annealing (SA) algorithm: moisture content and the relative abundance of C16:1, C18:3, C20:2, C22:0 and C22:1. The LDA-SA model allowed 100% of correct classifications for training (Figure 1). Furthermore, when using leave-one-out cross validation (LOO-CV), the model kept 100% of sensitivity, highlighting its robustness. A repeated K-fold CV was further performed to verify the accuracy of the proposed methodology, showing an average correct classification of 97.5% of the samples studied when 25% of the dataset was kept aside for internal validation. The satisfactory classification results achieved allow the conclusion that the six variables selected may be seen as geographical biomarkers and can be used to develop a robust tool for identifying the geographical origin of beech nuts.
- Potential use of the ATR-FTIR spectroscopy as an almond cultivar recognition tool: impact of sample and spectral pre-treatmentsPublication . Lamas, Sandra; Rodrigues, Nuno; Santamaria-Echart, Arantzazu; Palu, Igor; Manhique, Jocyla; Herrero, Baudilio; Lopéz-Cortés, Isabel; Pereira, José Alberto; Peres, António M.Three almond cultivars (Lauranne, Marinada, and Vairo) were studied, considering morphological parameters that showed statistical cultivar-dependence but not enabled accurate cultivar recognition. Alternatively, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was applied to whole endocarp, kernel, and ground almonds. Both transmittance spectra and respective derivatives (3400–2800 and 1900–600 cm of the three matrices were used to establish multivariate linear discriminant models, based on subsets of selected wavenumbers (6–33), allowing 90.5–99.7% of correct cultivar classification for repeated K-fold cross-validation. Ground almonds yielded the best results regardless of spectrum pre-treatment. While epicarp analysis offers less invasiveness, the use of raw transmittance spectra of ground almonds resulted into the most practical approach due to the need of fewer independent variables (less complex models), proving effective for cultivar identification via ATR-FTIR -chemometric tools. Overall, the findings point out that ATR-FTIR is a reliable tool for almond cultivar traceability.
- Thymus masticina L. – Composição e bioactividade de exemplares com diferentes origens geográficasPublication . Delgado, Teresa; Pilar, Marinero; Asensio-S.-Manzanera, M. Carmen; Asensio, Carmen; Herrero, Baudilio; Pereira, J.A.; Ramalhosa, ElsaO tomilho (Thymus sp.) e geralmente usado como especiaria e/ou erva medicinal com diversas propriedades farmacológicas, tais como anti-espasmódicas, anti-sépticas, anti-tússicas, expectorantes, entre outras. Os óleos essenciais extraídos do tomilho tem também encontrado uso na dieta humana, uma vez que tem sido demonstrada actividade antimicrobiana face a microrganismos patogénicos, tais como Staphylococcus aureus, Helicobacter pylori e Candida albicans.