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- Melipona scutellaris geopropolis: chemical composition and bioactivityPublication . Coutinho, Sónia; Matos, Vanessa; Seixas, Natália; Rodrigues, Hellen; Paula, Vanessa B.; Freitas, Lais; Dias, Teresa; Santos, Francisco de A.R.; Dias, L.G.; Estevinho, Leticia M.Geopropolis has been used in traditional medicine for centuries. In this study, the botanical origin, physicochemical profile, and biological activities of geopropolis from Melipona scutellaris harvested during rainy and dry seasons were investigated. Palynological analysis identified over 50 pollen types, with Schinus terebinthifolius and Cecropia being the predominant types. The analytical results were in line with those reported in the literature. Rainy-season geopropolis exhibited higher total phenol and flavonoid content (determined using High Performance Liquid Chromatography-25.13% and 3.92%, respectively) compared to the dry season (19.30% and 2.09%); the major peaks (naringin, gallic acid, and catechin) were similar among samples. Antioxidant capacity was assessed via DPPH, reducing power, and beta-carotene/linoleic acid discoloration assays. Rainy-season samples displayed superior antioxidant activity across methods. Antimicrobial effects were determined using microdilution, while the impact on the cholinesterase enzyme was quantified using 5-thio-2-nitrobenzoic acid accumulation. Anti-inflammatory and antimutagenic activities were assessed through hyaluronidase enzyme inhibition and by utilizing Saccharomyces cerevisiae ATCC-20113 cells. Both samples exhibited anti-inflammatory and antimutagenic properties. Moreover, a significant inhibition of acetylcholinesterase was observed, with IC50 values of 0.35 mu g/mL during the rainy season and 0.28 mu g/mL during the dry season. Additionally, the geopropolis displayed antimicrobial activity, particularly against Staphylococcus aureus. These findings suggest the therapeutic potential of M. scutellaris geopropolis in the context of inflammatory, oxidative, and infectious diseases.
- Quality of bee pollen submitted to drying, pasteurization, and high-pressure processing-A comparative approachPublication . Anjos, Ofélia; Seixas, Natália; Antunes, Carlos A.L.; Campos, Maria G.; Paula, Vanessa B.; Estevinho, Leticia M.Bee Pollen is a valuable and useful natural food product that can be used for different purposes, among which medical ones. This matrix is deemed a superfood because of its chemical composition, which is rich in nutrients and possesses significant bioactivities, including antioxidant and microbiological properties. Nevertheless, the storage conditions and processing methods must be optimized to maintain their properties and maximise their application. This work investigates the best bee pollen conservation process and its impact on individual con-stituents. Monofloral bee pollen was analysed for 30 and 60 days after three different storage processes (drying, pasteurization, and high-pressure pasteurization). The results showed a decrease mainly in fatty acid and amino acid content for the dried samples. The best results were obtained with high-pressure pasteurization, maintaining the proteins, amino acids and lipids characteristics of pollen and the lowest microbial contamination.
- The Effect of Incorporating Fermented Elderberries (Sambucus nigra) into Bread: Quality, Shelf Life, and Biological EnhancementPublication . Seixas, Natália; Paula, Vanessa B.; Dias, Teresa; Dias, Luís G.; Estevinho, Letícia M.Elderberries, known for their antioxidant, anti-inflammatory, and antiviral properties, have traditionally been used to prevent and treat infections and boost the immune system. By increasing the quantity and quality of certain compounds, fermentation can potentially make them more effective as food additives. The aim of this study was to evaluate the effect of incorporating fermented elderberries on the bioactivity and shelf life of a traditional bread. The elderberry fermentation process was optimised using Saccharomyces cerevisiae, guided by a Plackett–Burman experimental design. The aim was to assess the impact of incorporating fermented elderberries into bread on its bioactive properties and shelf life. The fermentation of the elderberries was found to enhance their bioactive compounds and antioxidant activity. The total phenolic content ranged from 8.63 to 20.56 mg GAE/g (in samples without and with 2% extract, respectively). The antioxidant capacity, measured using the FRAP method, also showed a significant increase with the addition of the extract (from 9.16 to 26.66 mg Fe (II) E/g of the sample). Furthermore, bread enriched with fermented elderberry extracts demonstrated an extended shelf life during the study period.
- Phenolic Class Analysis in Honey: Comparison of Classical and Single UV Spectrum MethodologiesPublication . Paula, Vanessa B.; Sousa-Dias, Miguel L.; Seixas, Natália; Combarros-Fuertes, Patricia; Estevinho, Leticia M.; Dias, L.G.The analytical results from a study of 16 honey samples (extra white to dark honey color range) of phenolic compounds obtained using the single UV spectrum methodology and classical spectrophotometric methods (Folin–Ciocalteu and AlCl3 methods) are presented. The first method quantified all classes of phenolic compounds in honey’s SPE-C18 extract: the total hydroxybenzoic acid content (concentrations between 0.37 ± 0.05 and 4.46 ± 0.37 mg of gallic acid/g of honey), total hydroxycinnamic acid content (0.13 ± 0.03 and 2.76 ± 0.13 mg of ferulic acid/g of honey), and total flavonoid content (0.15 ± 0.03 and 1.63 ± 0.17 mg of quercetin/g of honey). The total phenolic contents were, on average, 1.86 ± 0.72 and 1.78 ± 0.79 times higher than the results obtained for raw honey and the SPE-C18 extract, respectively, using the classical Folin–Ciocalteu method. The total flavonoid contents, on average, were 6.02 ± 3.14 times larger and 0.66 ± 0.33 times smaller than the results obtained using the classical AlCl3 method for raw honey and SPE-C18 extract, respectively.
- Análise preliminar de formulações Ayurvédicas como fonte potencial para cosméticosPublication . Zacharias, Alessandra; Martins, Valter; Paula, Vanessa B.; Morais, Jorge Sá; Sousa, Maria JoãoGhee (manteiga clarificada) é uma preparação Ayurvédica (medicina tradicional indiana) rica em PUFA’s, com potencial anti-inflamatório e antioxidante. Além do uso culinário, é usado em queimaduras, cicatrização e tratamento de doenças cutâneas. Rosmarinus officinalis L. e Rosa spp. apresentam atividades antibacteriana, anti-inflamatória, anti tumoral e antioxidante. Desde a antiguidade, estas plantas são utilizadas medicinalmente e na perfumaria. Com objetivo de avaliação para desenvolvimento de um cosmeceutico inspirado nesta etnofarmacologia, foram preparadas duas emulsões, utilizando, extrato aquoso e lipídico: 1- Alecrim (A); 2- Rosas (R). Foi avaliado o pH inicial A=7,71 e R=7,38 e após 7 dias A=7,75 e R=7,75. Para teste de estabilidade as amostras ficaram em fotoperíodo de luz day-light (16h/dia;8h/escuro), não apresentado alterações nas qualidades organoléticas da formulação mantendo a estabilidade. Na análise de cromatografia gasosa (GC) para deteção dos ácidos gordos verificou-se a presença de ácidos gordos saturados e insaturados nas duas amostras. Na amostra A os ácidos Palmítico, Mirístico e Esteárico foram os com maior expressão; na amostra R foram os ácidos Oléico, Palmítico e Linoleico. Foi testada resistência ás infeções microbiológicas da formulação com Staphylococos aureos, Echerichia coli, Pseudomonas aeruginosa e Candida albicans observando-se sensibilidade a estes agentes o que indica a necessidade de adicionar um conservante para tempos de prateleira longos. Como continuação da investigação pretende-se analisar a composição fitoquímica e bioatividades de extratos e óleos essenciais de novas plantas ayurvedicas, como a Centella asiatica L. para incorporação no cosmético a desenvolver.
- Mead production using immobilized cells of saccharomyces cerevisiae: Reuse of sodium alginate beadsPublication . Sousa-Dias, Miguel L.; Paula, Vanessa B.; Dias, L.G.; Estevinho, Leticia M.This work studied the production of mead using second category honey and the immobilized cells of Saccharomyces cerevisiae in sodium alginate, with concentrations of 2% and 4%, and their reuse in five successive fermentations. The immobilized cells with 4% alginate beads were mechanically more stable and able to allow a greater number of reuses, making the process more economical. The fermentation’s consumption of sugars with free cells (control) and immobilized cells showed a similar profile, being completed close to 72 h, while the first use of immobilized cells finished at 96 h. The immobilized cells did not significantly influence some oenological parameters, such as the yield of the consumed sugars/ethanol, the alcohol content, the pH and the total acidity. There was a slight increase in the volatile acidity and a decrease in the production of SO2. The alginate concentrations did not significantly influence either the parameters used to monitor the fermentation process or the characteristics of the mead. Mead fermentations with immobilized cells showed the release of cells into the wort due to the disintegration of the beads, indicating that the matrix used for the yeast’s immobilization should be optimized, considering the mead production medium.
- Recent advances in applied microbiology: EditorialPublication . Estevinho, Leticia M.; Combarros-Fuertes, Patricia; Paula, Vanessa B.The importance of microbiology has grown exponentially since the development of genomics, transcriptomics, and proteomics, making it possible to clarify microbial biogeochemical processes and their interactions with macroorganisms in both health and disease. Particular attention is being payed to applied microbiology, a discipline that deals with the application of microorganisms to specific endeavors, whose economic value is expected to exceed USD 675.2 billion by 2024. In the Special Issue “Recent Advances in Applied Microbiology”, twenty-four papers were published (four reviews and twenty original research papers), covering a wide range of subjects within applied microbiology, including: microbial pathogenesis, the health-promoting properties of microorganisms and their by-products, food conservation, the production of alcoholic beverages, bioremediation and the application of microbiology to several industrial processes.
- Análise preliminar da manteiga clarificada como fonte de um potencial cosmecêuticoPublication . Zacharias, Alessandra; Martins, Valter; Paula, Vanessa B.; Morais, Jorge Sá; Sousa, Maria JoãoGhee (manteiga clarificada) é uma preparação Ayurvédica (medicina tradicional indiana) rica em ácidos gordos essenciais com propriedades anti-inflamatória e antioxidante. Além do uso culinário, é usado na cicatrização de feridas, queimaduras e tratamento de doenças cutâneas. Shatadhauta ghrita é uma emulsão obtida, tradicionalmente, por cem lavagens do ghee, aumentando sua absorção cutânea. Mantém a pele hidratada, proporcionando baixa carga bacteriana potenciando a regeneração celular e histológica. Rosmarinus officinalis L. (Alecrim) e Rosa spp (Rosa) apresentam atividades antibacteriana, anti-inflamatória, antitumoral e antioxidante. Desde a antiguidade, estas plantas são utilizadas medicinalmente e na perfumaria. Com objetivo de avaliação para desenvolvimento de um cosmecêutico inspirado nesta etnofarmacologia, foram preparados dois shatadhautas, utilizando maceração lipídica com Alecrim (A) e Rosas (R) e extrato aquoso dessas plantas para as lavagens. Foi avaliado o pH inicial A=7,71 e R=7,38 e após sete dias A=7,75 e R=7,75. Para teste de estabilidade as amostras ficaram em fotoperíodo de daylith (16/dia;8/escuro), não apresentado alterações nas qualidades organoléticas da formulação mantendo a estabilidade, no final do ensaio. Foi testada resistência ás infeções microbiológicas da formulação com Staphylococos aureos, Echerichia coli, Pseudomonas aeruginosa e Candida albicans observando-se sensibilidade a estes agentes o que implica a necessidade de adicionar um conservante para tempos de prateleira longos. A cromatografia gasosa (GC) para deteção dos ácidos gordos verificando-se a presença de ácidos gordos saturados e insaturados. Na amostra A ác. Palmítico e ác. Mirístico; na R ác. Oléico e ác. Palmítico foram os com maior expressão.
- Propolis microencapsulation by double emulsion solvent evaporation approach: Comparison of different polymeric matrices and extract to polymer ratioPublication . Paulo, Filipa; Paula, Vanessa B.; Estevinho, Leticia M.; Santos, LúciaPropolis, a heterogeneous matrix produced by honeybees, is an antioxidant amongst other valuable biological properties. Nevertheless, the practical application of propolis, especially for the food industry, is still limited due to its relative high hydrophilicity and strong/unpleasant taste and aroma. Accordingly, microencapsulation arises a potential alternative approach to protect propolis compounds while allowing to mask its unpleasant sensory properties. The purpose of this study was to microencapsulate propolis extracts in lipophilic polymer-carriers using alternative propolis extract to polymer ratios – 1/4, 1/2 and 3/4 – by double emulsion solvent evaporation approach. The product yield was higher than the previously reported in the literature (80.3 ± 3.7% versus 68%). The encapsulation efficiencies (considering the encapsulated antioxidants and phenolic compounds) were independent from the propolis extract to polymer ratio, for the studied lipophilic polymer-carriers. The results of this work provide promising approaches for the manufacture of propolis extracts-loaded microparticles for further incorporation in functional matrices.
- Microbiological and Physicochemical Evaluation of Hydroxypropyl Methylcellulose (HPMC) and Propolis Film Coatings for Cheese PreservationPublication . Paula, Vanessa B.; Dias, L.G.; Estevinho, Leticia M.Dairy products are highly susceptible to contamination from microorganisms. This study aimed to evaluate the efficacy of hydroxypropyl methylcellulose (HPMC) and propolis film as protective coatings for cheese. For this, microbiological analyses were carried out over the cheese' ripening period, focusing on total mesophilic bacteria, yeasts and moulds, lactic acid bacteria, total coliforms, Escherichia coli, and Enterobacteriaceae. Physicochemical parameters (pH, water activity, colour, phenolic compounds content) were also evaluated. The statistical analysis (conducted using ANOVA and PERMANOVA) showed a significant interaction term between the HPMC film and propolis (factor 1) and storage days (factor 2) with regard to the dependent variables: microbiological and physicochemical parameters. A high level of microbial contamination was identified at the baseline. However, the propolis films were able to reduce the microbial count. Physicochemical parameters also varied with storage time, with no significant differences found for propolis-containing films. Overall, the addition of propolis to the film influenced the cheeses' colour and the quantification of phenolic compounds. Regarding phenolic compounds, their loss was verified during storage, and was more pronounced in films with a higher percentage of propolis. The study also showed that, of the three groups of phenolic compounds (hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids), hydroxycinnamic acids showed the most significant losses. Overall, this study reveals the potential of using HPMC/propolis films as a coating for cheese in terms of microbiological control and the preservation of physicochemical properties.