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- Storage methods, phenolic composition, and bioactive properties of Apis mellifera and Trigona spinipes pollenPublication . Santa Bárbara, Marivalda F.; Moreira, Manuela M.; Machado, Cerilene Santiago; Chambó, Emerson Dechechi; Pascoal, Ananias; Carvalho, Carlos Alfredo Lopes de; Sodré, Geni da Silva; Delerue-Matos, Cristina; Estevinho, Leticia M.The aim of this study was to evaluate the influence of lyophilization and drying in stove on phenolic compounds content and the biological activity of Apis mellifera and Trigona spinipes pollens produced in Brazil. In general, the bee pollen produced by T. spinipes presented highest antioxidant activity in dried and fresh samples assessed either by test of plasma ferric reduction capacity (FRAP) and free radical scavenging assay (DPPH) methods. For A. mellifera bee pollen the antioxidant activity was higher on the fresh samples. Nevertheless, b-carotene bleaching assay (BCB) and linoleic acid content were higher in T. spinipes samples, mainly in the fresh ones. Higher antioxidant activity was owing to higher content in phenolic compounds. Lyophilization method was the best for phenolic compounds’ conservation for both species. The bee pollen of both species has a high amount of flavonoids: kaempferol-3-O-glucoside was the most abundant in A. mellifera while for T. spinipes the most prevalent was resorcylic acidþepicatechin. All extracts presented antibacterial activity against Saphylococcus aureus (ATCC 43300)TM, (ESA 83138150), (ESA 32), Pseudomonas aeruginosa (ATCC 15442)TM, Pseudomonas aeruginosa (MRC.4) and (MRC.10). The methods used for storage influenced the biological properties of bee pollen from both species. Regarding the content of phenolic compounds, differences were observed amongst the pollen types: for A. mellifera these were best preserved with lyophilization, while for T. spinipes the three storage methods were equivalent.
- Botanical origin, physicochemical characterization, and antioxidant activity of bee pollen samples from the northeast of PortugalPublication . Pascoal, Ananias; Chambó, Émerson Dechechi; Estevinho, Leticia M.Bee pollen is a beehive product that has increased the attention of both researchers and consumers. The main goal of the present study was to evaluate 69 heterofloral dried bee pollen samples harvested in two regions of the northeast of Portugal (Mogadouro and Vimioso). For such, the botanical origin of the samples and several physicochemical parameters (moisture, pH, water activity, reducing sugar, proteins, lipids, ash, fibers, carbohydrates, energy, total phenolic, and flavonoids) were evaluated and the antioxidant potential was studied. The average percentage of pollen grains from Erica spp. and Cytisus spp. was higher (p<0.05) in samples from Mogadouro, while Cistus spp., Castanea spp., and Echium spp. were more abundant in Vimioso samples. The pollen harvested in Vimioso presented higher values on proximate parameters as compared to other samples:moisture (4.61 ± 0.84%), lipids (4.94 ± 0.94%), ash (3.28 ± 0.93%), fiber (3.55 ± 1.11%), and carbohydrates (66.60 ± 3.52%).On the other hand, higher values were obtained on Mogadouro samples regarding water activity (0.41 ± 0.11), protein (26.09 ± 2.86%), total phenols (26.71 ± 6.19, expressed as mg of Gallic acid equivalents GAE/g), and antioxidant activity (assessed by b-carotene bleaching [3.35 ± 1.17mg/mL] or the free radical scavenging assay [2.98 ± 0.63mg/mL]). All bee pollen samples had a great botanical similarity, yet the dominant pollen types were different between the two regions allowing the classification of the samples according to the geographical origin.
- Microbiological quality and sensory evaluation of new cured products obtained from sheep and goat meatPublication . Tolentino, Georgina Santos; Estevinho, Leticia M.; Pascoal, Ananias; Rodrigues, Sandra; Teixeira, AlfredoThe present work aims to study the effect of species and seasoning time on the physicochemical, microbiological and sensory characteristics of cured legs of sheep and goats. Three cure periods were used: two for sheep and one for goat legs. Legs of lamb were cured for 7 and 8 months whereas legs of goat were cured for 8 months only. Samples were evaluated regarding pH, water activity and indicators of food microbial q uality and safety. A trained panel carried out the sensory analysis, with aroma, texture, appearance and taste being the evaluated parameters. Significant differences were detected between the amount of aerobic mesophiles of the products cured during 7 months and the sheep legs cured during 8 months. Moulds and yeasts were between 1.81 × 106 ± 1.73 × 106 and 3.97 × 106 ± 5.45 × 106 colony-forming units/g, whereas total coliforms varied from 2.80 × 102 ± 4.13 × 102 to 1.31 × 104 ± 2.39 × 104. All samples were negative for toxigenic species. Concerning sensory analysis, hardness and taste persistence were the attributes that presented the highest and the lowest discriminative power, respectively. In general, the panel was able to characterise and distinguish the samples. The cured legs of goats were characterised as harder and as less succulent than those obtained from sheep. Sheep meat with larger time of cure was the brightest, whereas the one with a smaller time of cure was the most succulent. However, goat meat presented higher values of rancid and acid flavour. Sheep meat submitted to longer processing presented the most intense flavour and sheep meat with an inferior cure period presented the lowest intensity in all flavour attributes. This paper describes, for the first time in Portugal, the production and characterisation of cured legs of sheep and goats as a strategy to enhance economic value to good quality products obtained from animals of second category.
- Impact of fining agents on the volatile composition of sparkling meadPublication . Pascoal, Ananias; Anjos, Ofélia; Feás, Xesús; Oliveira, José M.; Estevinho, Leticia M.Sparkling mead is obtained by secondary fermentation of the mead involving the addition of starter yeast culture, sucrose, nutrients and fining agents. The aim of this study was to evaluate the effect of different fining agents (tannins vs combined fining agents) on the volatile composition of sparkling mead. Sparkling mead was produced from a base mead using a commercial yeast strain (Saccharomyces bayanus) and the volatile compounds were determined by gas chromatography–flame ionisation detection and gas chromatography–mass spectrometry. Thirty six volatile compounds were quantified and the major groups were alcohols (73.2%), acetates (19.1%), carbonyl compounds (5.5%) and ethyl esters (1.2%), represented by 3-methyl-1-butanol, ethyl acetate, acetaldehyde and monoethyl succinate, respectively. The remaining compounds were present at <1%. Eleven volatile compounds exhibited odour activity values >1, with ethyl octanoate and ethyl hexanoate contributing to the aroma of sparkling mead, with fruity, strawberry and sweet notes. The combined fining agents caused a marked decrease in the concentration of volatile compounds compared with tannins. In general, 3-ethoxy-1-propanol, ethyl lactate, ethyl octanoate, diethyl succinate, diethyl malate, monoethyl succinate, 2-methylpropanoic acid, hexanoic acid, octanoic acid, acetaldehyde, acetoin, furfural, benzaldehyde, 5-hydroxymethylfurfural, trans-furan linalool oxide, cis-furan linalool oxide and 4-oxo-isophorone decreased in concentration. Conversely, 1-propanol and 2-methylpropanoic acid (tannins) and ethyl butyrate (combined fining agents) increased in concentration. The remaining volatile compounds were not affected. Significant differences (p < 0.05) were found for 19 volatile compounds independently of the type of fining agents used.
- Developments in the fermentation process and quality improvement strategies for mead productionPublication . Iglesias, Antonio; Pascoal, Ananias; Choupina, Altino; Carvalho, Carlos Alfredo Lopes de; Feás, Xesús; Estevinho, Leticia M.Mead is a traditional alcoholic drink derived from the fermentation of diluted honey in the presence of appropriate yeast. Its modern production, in general terms, involves the addition of nutrients to initial diluted honey, pasteurization, yeast inoculation, fermentation and removal of impurities. Undesirable events along the process have been reported; among them, we highlight: delayed or arrested fermentations, modified and unpleasant sensory and quality parameters of the final product. These problems have been linked to the inability of yeasts to accomplish their role in extreme growth conditions. Emphasis has also been placed on the long fermentation times required, ranging from weeks to months, particularly when traditional procedures are applied and when the honey concentration is low. A series of alterations to the must and technological changes have been proposed in order to optimize the mead production process. In this context, this review examines the evidence that aims to improve meads’ quality and make the production process easier and more efficient, by clarifying the source of unexpected events, describing the implementation of different fermentative microorganisms and using new methodologies.
- Evaluation of the sensory quality of monofloral honeyPublication . Estevinho, Leticia M.; Lopes, Sara; Pascoal, Ananias; Carvalho, MarietaHoney is an alimentary product much appreciated due to his aroma, flavor and nutritional characteristics. The sensorial analysis is important in the evaluation of the quality and authenticity of monofloral honeys. It considers attributes as color, aroma, consistence and flavor, which are interlinked and depend on the volatile compounds related with the fragrance of the flowers where the nectar was collected. The aroma and the flavor are also related directly with honeys’ color. The objective of this work was to evaluate the pollinic profile and the sensorial characteristics of four honeys from biological mode of production. The pollen analysis indicated that all of the analyzed honeys were monofloral,presenting as dominant pollen Lavandula sp. (45.83%), Erica sp. (49.69%), Prunus sp. (61.91%) and Castanea sp. (69.01%). The results obtained in the sensorial analysis performed by the consumer’s panel were treated by the Generalized Procrustes method. It was verified that the attributes that the consumers managed to evaluate more easily and whose contribution for the global appreciation was more accentuated were the color, the flavor and the consistence. The cherry tree honey presented higher values in the scale of preferences in terms of global appreciation, color, flavor, consistence and intermediate values regarding the aroma. Concerning the heather honey, aroma was the most valued attribute. Honeys from chestnut and rosemary were the ones that received lowest punctuation.
- The Role of Honey and Propolis in the Treatment of Infected WoundsPublication . Pascoal, Ananias; Feás, Xesús; Dias, Teresa; Dias, L.G.; Estevinho, Leticia M.Honey is defined as the natural substance produced by Apis mellifera bees from plant nectar, from secretions of the living parts of plants, or from the excretions of plant sucking insects feeding on the living parts of plants.1,2 Honeybees collect, transform, and combine this with specific substances of their own, and then store it and leave it in the honeycomb to ripen and mature. This natural product is generally composed of a complex mixture of carbohydrates and other less common substances, such as organic acids, amino acids, proteins, minerals, vitamins, lipids, aroma compounds, flavonoids, pigments, waxes, pollen grains, several enzymes and other phytochemicals.3 5 However, the specific composition depends on many factors, such as the nectar composition of the source plant, the species of bee, the climate, environmental and seasonal conditions, agricultural practices and treatment of honey during extraction and storage.6-9 As a natural, unprocessed and easily digested food, honey plays an important role in the human diet, and is also used in pharmaceutical and cosmetic industries.10 Modern science has studied the medical significance of honeys in healing wounds and burns,11 oncology care,12 as well as its antioxidant and antimicrobial properties.
- Biological activities of commercial bee pollens: antimicrobial, antimutagenic, antioxidant and anti-inflammatoryPublication . Pascoal, Ananias; Rodrigues, Sandra; Teixeira, Alfredo; Feás, Xesús; Estevinho, Leticia M.Bee pollen is considered, since memorable times, a good source of nourishing substances and energy. The present study aimed to evaluate the biological activities of eight commercial bee pollens purchased from the market. The origin of sample A was not specified in the labeling; samples B, C, D and G were from Portugal and the remaining were from Spain. The sample E presented the highest value of phenolics (32.15 ± 2.12 mg/g) and the H the lowest (18.55 ± 095 mg/g). Sample C had the highest value of flavonoids (10.14 ± 1.57 mg/g) and sample H the lowest (3.92 ± 0.68 mg/g). All the samples exhibited antimicrobial activity, being Staphylococcus aureus the most sensitive and Candida glabrata the most resistant of the microorganisms studied. All the samples exhibited antimutagenic activity, even though some samples were more effective in decreasing the number of gene conversion colonies and mutant colonies. Regarding the antioxidant activity, assessed using two methods, the more effective was sample B. The anti-inflammatory activity, assessed using the hyaluronidase enzyme, was highest in samples B and D. Pearson’s correlation coefficients between polyphenols, flavonoids, antioxidant activity and antimicrobial activity were computed. It was also performed a discriminant analysis.
- An overview of the bioactive compounds, therapeutic properties and toxic effects of apitoxinPublication . Pascoal, Ananias; Estevinho, Maria Manuela; Choupina, Altino; Sousa-Pimenta, Mário; Estevinho, Leticia M.Apitoxin, also known as bee venom (BV), is produced in two specialized abdominal glands of worker bees and is used as a defence weapon of bees’ colony (Choi et al., 2015; Zhang et al., 2016). In addition, this natural product has been used since the ancient times to relieve pain and to treat chronic inflammatory diseases such as rheumatoid arthritis, tendinitis, bursitis, skin conditions and even neurologic disorders (Moreno and Giralt, 2015). This natural product is a light-yellow liquid, characterized by a bitter taste, pungent smell and a pH ranging from 4.5 to 5.5 (Eze et al., 2016; Hossen et al., 2017). Some studies have described that 88% of BV is water, yet its specific composition varies depending on bee’ species and season (Moreno and Giralt, 2015). Indeed, BV has been reported to contain a complex of biologically active compounds among which enzymes (phospholipase A2 [PLA2], lysophospholipase, hyaluronidase, acid phosphomonoesterase; α-glucosidase, dipeptidyl peptidase IV and vitellogenin), peptides (melittin [MLT], apamin, mast cell degranulating [MCD], mastocytolytic peptide, scapin, adolapin, minimine; apidaecin; tertiapin; melittin F; cadiopep; procamine A, B, pamine, and proteaseinhibitors), biogenic amines (histamine, dopamine, noradrenaline, norepinephrine, neurotransmitters) and other compounds such as amino acids (γ-aminobutyric acid, α-amino acids), carbohydrates (glucose, fructose), pheromones (Iso-pentyl acetate, n-buttyl acetate, iso-pentanol, n-hexyl acetate, n-octyl acetate, 2-nonanol, n-decyl acetate, benzyl acetate, benzyl alcohol and (2)-11 –eicosen-1-ol) and minerals (P, Ca and Mg) (Nguyen et al., 2015; Tusiimire et al., 2015; Rady et al., 2017; Moga et al., 2018; Lee et al., 2018). Among these compounds, MLT is the main therapeutic ingredient of BV, representing between 40 and 60% of the dry weight (Abd-Elhakim et al., 2014).
- Effect of temperature on the bioactive properties of bee pollenPublication . Pascoal, Ananias; Rocha, Joana; Choupina, Altino; Pereira, Ana Paula; Santos, Luís; Estevinho, Leticia M.Bee pollen is flower pollen collected by the honey bee, Apis mellifera, for the purpose of feeding its larvae in the early stages of development. It is recognized to be a valuable apitherapeutic product with potential for medical, health and nutritional applications. The objective of this work was to compares the effect of different storage conditions in the bioactive compounds and biological properties of bee pollen. The amount in phenolics compounds determined by the method of Folin-Ciocalteu varied from 32.64 to 48.40 mg GAE/g, for the dehydrated and refrigerated samples, respectively. Significant differences were verified among the two conservation processes. the amount in total flavonoids determined by the method chloride of aluminum were not verified among significant differences in the samples (6.58 mg CAE/g) and (6.99 mg CAE/g).Concerning the amount of total flavonoids determined by the method of aluminum chloride were not significant differences between the dehydrated (6.58 mg of DEA / g) and refrigerated samples (CAE 6.99 mg / g). The antioxidant capacity of BP extracts was assessed through the scavenging effect on DPPH (2.2-diphenyl-1-picrylhydrazyl) and reducing power. The concentration-dependent antioxidative capacity was verified in DPPH and reducing power assays. Low values of EC50 on DPPH scavenging assay were obtained for fresh and dehydrated samples 0.74 and 1.16 mg/mL, respectively. For reducing power the values obtained for the refrigerated samples and dehydrated were similar. The high activity of refrigerated samples could be related with the conservation process. Regarding to phenolics compounds determined by HPLC method, were identified four (4) families, flavones being the most abundant one in the refrigerated and dehydrated samples. We also verified that the presence of pollen differentially affected the growth of bacterium Gram-positive (Staphylococcus xylosus, Staphylococcus epidermidis), Gram-negative (Shigella spp, Klebsiella pneumoniae) and yeasts (Cândida parapilosis, Cândida menbranifaciens, Cândida gllabrata) under study, depending this on the microorganism and the method of BP conservation.