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- Enzyme inhibitory potential of Ligustrum lucidum Aiton berriesPublication . Paula, Vanessa Branco; Delgado, Teresa; Campos, Maria da Graça; Anjos, O.; Estevinho, Letícia M.Ligustrum lucidum Aiton and its berries have been used in Chinese traditional medicine for around two thousand years. In the present study, L. lucidium berries harvested in two regions of Portugal were studied. Haemolytic activity and inhibition of oxidative haemolysis as well as the enzyme inhibitory activities (α-amylase enzyme and acetylcholinesterase) were assessed. Results suggest that the different biological activities varied according to the region where samples were collected. Results demonstrated that the sample obtained from region R1 was the most efficient extract for all parameters evaluated, presenting the lowest values of IC50, 10.67 ± 0.46 μg/mL for the inhibition of erythrocyte oxidative haemolysis, 58.28 ± 3.77 μg/mL for the α-amylase enzyme and 67.67 ± 2.10 μg/mL for the acetylcholinesterase inhibition. L. Lucidum berries may be an interesting source of compounds for use in the development of the therapeutic armamentarium for diseases where enzymatic disruption is believed to play a role
- Computational intelligence applied to discriminate bee pollen quality and botanical originPublication . Gonçalves, Paulo; Estevinho, Letícia M.; Pereira, Ana Paula; Sousa, João M.C.; Anjos, O.The aim of this work was to develop computational intelligence models based on neural networks (NN), fuzzy models (FM), and support vector machines (SVM) to predict physicochemical composition of bee pollen mixture given their botanical origin. To obtain the predominant plant genus of pollen (was the output variable), based on physicochemical composition (were the input variables of the predictive model), prediction models were learned from data. For the inverse case study, input/output variables were swapped. The probabilistic NN prediction model obtained 98.4% of correct classification of the predominant plant genus of pollen. To obtain the secondary and tertiary plant genus of pollen, the results present a lower accuracy. To predict the physicochemical characteristic of a mixture of bee pollen, given their botanical origin, fuzzy models proven the best results with small prediction errors, and variability lower than 10%.
- Influence of the storage conditions (frozen vs dried) in health‐related lipid indexes and antioxidants of bee pollenPublication . Estevinho, Letícia M.; Dias, Teresa; Anjos, O.Following harvest, bee pollen must be submitted to processing in order to maintain properties for consumers’ health insurance. In this study, the changes on the lipid profile, contents of vitamin C, β‐carotene and lycopene of bee pollen samples submitted to two conservation methods (freezing and drying) are evaluated. Eleven fatty acids, eight saturated, one monounsaturated, and two polyunsaturated are quantified. The PUFA/SFA ratio ranges from 1.18 to 3.95 g 100−1 g−1 and is significantly higher in the frozen extracts. On the other hand, the ratio n6:n3 (ranging between 0.36 and 0.86 g 100−1 g−1) did not differ among processing methodologies, for most of the cases. The atherogenicity (AI) and thrombogenecity (TI) indexes are similar among preservation processes and coherent with the found on other health‐promoting foods. The contents of vitamin C, β‐carotene and lycopene are, for all samples, significantly superior in the frozen bee pollen.
- FTIR–ATR spectroscopy applied to quality control of grape-derived spiritsPublication . Anjos, O.; Santos, António J.; Estevinho, Leticia M.; Caldeira, IldaThe Fourier transform infrared (FTIR) spectroscopic method with attenuated total reflectance (ATR) was used for predicting the alcoholic strength, the methanol, acetaldehyde and fusel alcohols content of grape-derived spirits. FTIR-ATR spectrum in the mid-IR region (4000-400 cm(-1)) was used for the quantitative estimation by applying partial least square (PLS) regression models and the results were correlated with those obtained from reference methods. In the developed method, a cross-validation with 50% of the samples was used for PLS analysis along with a validation test set with 50% of the remaining samples. Good correlation models with a great accuracy were obtained for methanol (r(2)=99.4; RPD=12.8), alcoholic strength (r(2)=97.2; RPD=6.0), acetaldehyde (r(2)=98.2; RPD=7.5) and fusel alcohols (r(2) from 97.4 to 94.1; RPD from 6.2 to 4.1). These results corroborate the hypothesis that FTIR-ATR is a useful technique for the quality control of grape-derived spirits, whose practical application may improve the efficiency and quickness of the current laboratory analysis.
- Standard methods for pollen researchPublication . Campos, Maria da Graça; Anjos, O.; Chica, Manuel; Campoy, Pascual; Nozkova, Janka; Almaraz-Abarca, Norma; Barreto, Lídia; Nordi, João Carlos; Estevinho, Letícia M.; Pascoal, Ananias; Paula, Vanessa Branco; Chopina, Altino; Dias, Luis G.; Tešić, Živoslav L. J.; Mosić, Mirjana D.; Kostić, Aleksandar Ž.; Pešić, Mirjana B.; Milojković-Opsenica, Dušanka M.; Sickel, Wiebke; Ankenbrand, Markus J.; Grimmer, Gudrun; Steffan-Dewenter, Ingolf; Keller, Alexander; Förster, Frank; Tananaki, Chrysoula H.; Liolios, Vasilios; Kanelis, Dimitrios; Rodopoulou, Maria-Anna; Thrasyvoulou, Andreas; Paulo, Luísa; Kast, Christina; Lucchetti, Matteo A.; Glauser, Gaëtan; Lokutova, Olena; Muradian, Lígia Bicudo de Almeida; Szczęsna, Teresa; Carreck, Norman L.“Bee pollen” is pollen collected from flowers by honey bees. It is used by the bees to nourish themselves, mainly by provid ing royal jelly and brood food, but it is also used for human nutrition. For the latter purpose, it is collected at the hive entrance as pellets that the bees bring to the hive. Bee pollen has diverse bioactivities, and thus has been used as a health food, and even as medication in some countries. In this paper, we provide standard methods for carrying out research on bee pollen. First, we introduce a method for the production and storage of bee pollen which assures quality of the product. Routine methods are then provided for the identification of the pollen’s floral sources, and determination of the more important quality criteria such as water content and content of proteins, carbohydrates, fatty acids, vitamins, alkaloids, phen olic and polyphenolic compounds. Finally, methods are described for the determination of some important bioactivities of bee pollen such as its antioxidant, anti-inflammatory, antimicrobial and antimutagenic properties.
- Development of blueberry liquor: influence of distillate, sweetener and fruit quantity.Publication . Caldeira, Ilda; Lopes, Daniel; Delgado, Teresa; Canas, Sara; Anjos, O.In this work different formulations of blueberry liquor were tested and characterised based on their physico-chemical and sensory characteristics.
- Sugar identification of Lavandula spp. honeyPublication . Estevinho, Letícia M.; Elamine, Youssef; Miguel, Maria Graça; Anjos, O.Sugar identification of Lavandula spp. Honey.
- HPLC/DAD fingerprint of standardize extracts from Ligustrum lucidum Aiton berries, for bioactive activity screening.Publication . Delgado, Teresa; Paula, Vanessa Branco; Campos, Maria da Graça; Farinha, Nelson; Caeiro, André; Estevinho, Letícia M.; Anjos, O.HPLC/DAD fingerprint of standardize extracts from Ligustrum lucidum Aiton berries, for bioactive activity screening.
- Effect of extreme heat processing on the Moroccan Zantaz’ honey antioxidant activitiesPublication . Elamine, Youssef; Anjos, O.; Estevinho, Letícia M.; Lyoussi, Badiâa; Aazza, Smail; Miguel, Maria GraçaThe effect of an extreme heat processing on Zantaz honey samples was studied using a panel of physicochemical parameters, antioxidant activities and FTIR-ATR spectroscopy. Honey samples were heated at 121 °C for 30 min and the heat processing effect was confirmed indirectly through the assessment of hydroxymethylfurfural content, for which the values increased significantly (p < 0.01), and diastase activity, which was totally absent after the thermal processing. Besides, the effects of the heat on the antioxidant activities were diverse. Indeed, while the ability to scavenge 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid cation radicals (ABTS·+) and 2,2-diphenyl-1-picrylhydrazyl radicals was enhanced (p < 0.05 only for ABTS·+), after the heat processing, nitric oxide radicals scavenging activity was reduced drastically (p < 0.01). Regarding the chelating power, it was totally abolished following heating. Other activities showed no significant alteration. The initial values of antioxidant activities seem to be determinant in the changes occurring after the heat processing. Amongst the analysed parameters, following the heat processing, the honey colour was the variable where the influence of baseline values was the greatest. The spectral analyses confirmed that FTIR-ATR is a useful technique to discriminate the chemical differences occurring in honey after heat processing.
- Evaluation of FT-Raman and FTIR-ATR spectroscopy for the quality evaluation of Lavandula spp. HoneyPublication . Anjos, O.; Guiné, Raquel P.F.; Santos, António J.; Paula, Vanessa Branco; Pereira, Helena; Estevinho, Letícia M.Monofloral Lavandula spp. honey is very appreciated by consumers due to its characteristic and pleas antaroma and flavor. Given the economic importance of this ype of honey, it is important to develop a rapid and nonexpensive methodology that allows certifying its quality. In this context, this study aimed to compare the applicability and accuracy of FTIR-ATR and FT-Raman techniques for the quality evaluation of Lavandula spp. honey. Calibration models, with PLS regression models, were obtained for both methodologies concerning the following parameters: total acidity, reducing sugars, hidroximetilfurfural (HMF), electrical conductivity, ash, proline content, diastase activity, apparent sucrose, total flavonoids, and total phenolic contents. The calibration models had high regression coefficients, r 2 (FTIR-ATR: 0.965–0.996; FT-Raman: 0.983–0.999), high ratios of performance to deviation, RPD (FTIR-ATR: 5.4–15.7; FT-Raman: 7.6–53.7), and low root mean square errors (RMSEs; FTIR-ATR: 0.005–3.0; FT-Raman: 0.004–1.02). These results corroborate the potentiality of FTIR-ATR and FT-Raman for quality evaluation and evaluation of the chemical properties of Lavandula spp. honey even though FT-Raman technique provided more accurate models.