Browsing by Author "Barros, Joana"
Now showing 1 - 8 of 8
Results Per Page
Sort Options
- #088. Prevalência de periodontite apical numa população portuguesa associada aos hábitos tabágicosPublication . Herdade, Ana Isabel; Noites, Rita; Cardoso, Miguel Agostinho; Rodrigues, Cláudia; Vaz, Irene Pina; Barros, JoanaObjetivos: Determinar a prevalência de periodontite apical (PA) numa população portuguesa e perceber a influência do tabaco no status periapical. Materiais e métodos: Foram avaliados 402 processos clínicos e respetivas radiografias panorâmicas, de pacientes da Clínica Dentária do Instituto de Ciências da Saúde de Viseu da Universidade Católica Portuguesa, com pelo menos 8 dentes em boca e com mais de 18 anos, que foram tratados ou estão em tratamento desde janeiro de 2015 a março de 2016. Procedeu‐se ao registo da presença de PA associada ao hábito comportamental do tabaco, por indivíduo. A classificação quanto à severidade das lesões periapicais foi realizada segundo o índice periapical de Ørstavik (PAI). Os hábitos tabágicos foram registados em não fumadores e fumadores. Resultados: A média de idades da população estudada foi de 46,81 ± 17,5 anos, 57,2% eram do género feminino e 42,8% do género masculino, e a prevalência de indivíduos fumadores foi de 23,9% (do género masculino: 29,7% fumadores; do género feminino: 19,6% fumadores). A prevalência de PA por indivíduo foi de 53,5% sendo que, do total de indivíduos fumadores, 66,7% apresentou pelo menos uma lesão de PA (PAI > = 3). Os valores da associação entre hábitos tabágicos e prevalência de PA apresentaram‐se significativamente relacionados (p < 0,05). Conclusões: A associação entre a prevalência de PA e os hábitos tabágicos, verificada neste estudo, salienta a importância que tem sido atribuída recentemente à influência do status oral na saúde geral do indivíduo.
- Antibacterial and antioxidant potential of aqueous extracts of bio-residues from agrocybe cylindracea and pleurotus ostreatus myceliumPublication . Sousa, Ana Sofia; Nunes, Catarina; Barros, Joana; Ferreira, Inês; Freitas, Ana C.; Morais, Alcina M. M. B.; Nunes, João; Pintado, ManuelaThe production of fresh mushrooms results in a large quantity of bio-residues, which may account for more than 20% of a crop volume and contributes to production costs and environmental impact, if not used. These products consist mainly of stalks, mushrooms of irregular dimensions and shape and basal material. Thus, the main objective of MicoBioExtract project is the valorisation of these bio-residues and the development of add-value by-products with bioactive compounds such as polysaccharides and phenolic compounds produced by mushrooms. In the present work, the aqueous extracts from Agrocybe cylindracea byproducts (ACB) and Pleurotus ostreatus mycelium (POM) were evaluated for potential antioxidant and antimicrobial activities. Water soluble substances were extracted from mushrooms according to two different methods. In method 1 it was performed a hot extraction (extract 1A; 90 °C; 1 h; 500 rpms). In method 2, the biomass was submitted to an extraction at room temperature (extract 2B) and the resulting residue was extracted with hot water (extract 2C; 90 °C; 1 h; 500 rpms). The aqueous extracts from POM were obtained only by method 1. Extracts were lyophilized and their bioactivity evaluated measuring the antioxidant (ABTS, DPPH and ORAC) and antimicrobial (determination of the minimum inhibitory concentration – MIC) activities. The mutagenicity was also tested (Ames assay with and without S9). Moreover, it was determined the total phenolics content of the extracts and α and β – glucans (Folin Ciocalteu and Beta-Glucan Assay methods, respectively). The results obtained from antioxidant methods showed that all extracts from both mushrooms are a potential source of natural antioxidant and phenolic compounds. According to ABTS, extract 2B from ACB showed the best value with 8.48±0.33 mg ascorbic acid equivalent (AAE)/g dry extract and 4.14±0.52 mg AAE/g dry extract for POM. Regarding the antimicrobial activity, MIC results showed that ACB and POM extracts inhibited the growth of Gram- (Salmonella enteritidis) and Gram+ (Bacillus cereus and Listeria monocytogenes). Concerning the mutagenicity, the results showed no toxic effect except for extract 1A from ACB. Regarding the β-glucan content, the extracts from ACB presented higher content of β-glucan than the C extracts from POM. Thus, aqueous extracts from mushroom bio-residues showed potential antioxidant and antimicrobial properties and to develop a circular bioeconomy approach.
- Aqueous extracts from agrocybe cylindracea and pleurotus ostreatus as source of antioxidant coatingsPublication . Marçal, Sara; Sousa, Sofia; Antunes, Filipa; Costa, Cristina; Ferreira, Inês; Barros, Joana; Nunes, João; Pintado, ManuelaAgrocybe cylindracea and Pleurotus ostreatus mushrooms are rich in polysaccharides and phenolic compounds with antioxidant and antimicrobial properties. Therefore, these mushrooms can be a good source of natural food preservatives and edible coatings. The main goal of this study was to develop an edible coating with antioxidant activity. Edible coatings are composed of biopolymers and may be carriers of additives with bioactive properties. This study developed an aqueous extraction process that allows the extraction of biopolymers and bioactive compounds (eg. phenolic compounds) from A. cylindracea and P. ostreatus mushrooms, with antioxidant activity, which can be used as preservative edible coating. To accomplish this, after a pre-treatment by maceration of frozen mushrooms two consecutive aqueous extractions were applied, where the first was at room temperature (A) and the second (B) was hot extraction (90ºC; 1h; 5 000rpm). Extracts were lyophilized and the extraction yields were determined. Total phenolics content was determined through Folin Ciocalteu and antioxidant activity through ABTS method. The yields of extracts A and B from P. ostreatus were 33.60% ± 0.39 and 15.18% ± 0.70. The yields of extracts A and B from A. cylindracea were 30.91% ± 0.89 and 14.77% ± 1.49, respectively. These results are in agreement with yields of A. cylindracea hot-water extracts reported by Tsai, Huang and Mau,2006. Phenol content of extracts from A. cylindracea (extract A: 13.35 ± 0.55; extract B: 12.79 ± 0.67 mg gallic acid equivalent (GAE) per g of dry extract) were higher than phenol content of extracts from P. ostreatus (extract A: 10.28 ± 0.70; extract B: 11.52 ± 0.62 mg GAE per g of dry extract). The ABTS radical cation-scavenging activity was also higher in extracts from A. cylindracea (extract A: 12.04 ±1.26; extract B: 6.78 ± 0.44mg ascorbic acid equivalent (AAE) per g of dry extract) than extracts from P.ostreatus (extract A: 6.39 ± 1.45; extract B: 5.75 ± 0.49mg AAE per g of dry extract). Results of this study indicate that A. cylindracea has more antioxidant activity than P. ostreatus, but both mushrooms are potential sources of natural antioxidant preservatives and polysaccharides to produce bioactive edible coatings.
- Phenolics content and antioxidant activity of aqueous extracts from bio-residues of agrocybe cylindraceaPublication . Sousa, Ana Sofia; Marçal, Sara; Nunes, Catarina; Barros, Joana; Ferreira, Inês; Freitas, Ana C.; Morais, Alcina M. M. B.; Nunes, João; Pintado, ManuelaMushrooms are known as a rich source of functional and bioactive compounds. Among these, phenolic compounds as important antioxidants are included. In the present work, the antioxidant potential and total phenolic compounds from bio residues obtained from edible mushroom production were evaluated in order to develop a circular bioeconomy approach. The studied species was Agrocybe cylindraceae. The extraction was performed using water as the only solvent, in order to obtain a process as green as possible and with minimal costs and it can be easily scaled up at industrial level. The aqueous extracts were obtained according to two different methods (1 and 2). In method 1, a hot extraction was performed (90°C; 1h; 500 rpms; extract 1A). In method 2, a temperature room extraction was done (extract 2A) and the resulting residue was subsequently extracted with hot water (90 °C; 1 h; 500 rpms; extract 2B). Extracts were freeze-dried and the extraction yields were determined. The content of total phenolic compounds was determined using Folin-Ciocalteu method. The antioxidant activity was also evaluated by ABTS, DPPH and ORAC assays. The extraction yields relative to aqueous extracts 1A, 2A and 2B from A. cylindraceae were 39.5 ± 1.5 %, 34.4 ± 1.2 % and 11.4± 0.8 %. The total phenolic contents obtained was 13.4 ± 0.3, 12,28 ± 0.01 and 12.3 ± 0.3 mg gallic acid equivalents per g dry extract for extracts 1A, 2A and 2B, respectively, which values are again lower than values reported in literature for ethanolic extracts, as expected. Regarding the antioxidant activity the results showed that the extracts of A. cylindraceae are a possible source of natural antioxidants. According to ABTS assay, the results were: 10 ± 1 (1A); 8.4 ± 0.1 (2A); 8.3 ± 0.9 (2B) mg ascorbic acid equivalent per g dry extract. According to the results, these extracts could still be considered as a natural source of antioxidants. Thus, the valorisation of these bio-residues through the development of value-added “green” products is an opportunity to increase the sustainability of the mushroom production chain.
- Phenolics content and antioxidant activity of aqueous extracts from bio-residues of agrocybe cylindraceaPublication . Sousa, Ana Sofia; Marçal, Sara; Nunes, Catarina; Barros, Joana; Ferreira, Inês; Freitas, Ana C.; Morais, Alcina M. M. B.; Nunes, João; Pintado, ManuelaMushrooms are known as a rich source of functional and bioactive compounds. Among these, phenolic compounds as important antioxidants are included. In the present work, the antioxidant potential and total phenolic compounds from bio-residues obtained from edible mushroom production were evaluated in order to develop a circular bioeconomy approach. The studied species was Agrocybe cylindraceae. The extraction was performed using water as the only solvent, in order to obtain a process as green as possible and with minimal costs and it can be easily scaled up at industrial level. The aqueous extracts were obtained according to two different methods (1 and 2). In method 1, a hot extraction was performed (90°C; 1h; 500 rpms; extract 1A). In method 2, a temperature room extraction was done (extract 2A) and the resulting residue was subsequently extracted with hot water (90 °C; 1 h; 500 rpms; extract 2B). Extracts were freeze-dried and the extraction yields were determined. The content of total phenolic compounds was determined using Folin-Ciocalteu method. The antioxidant activity was also evaluated by ABTS, DPPH and ORAC assays. The extraction yields relative to aqueous extracts 1A, 2A and 2B from A. cylindraceae were 39.5 ± 1.5 %, 34.4 ± 1.2 % and 11.4± 0.8 %. The total phenolic contents obtained was 13.4 ± 0.3, 12,28 ± 0.01 and 12.3 ± 0.3 mg gallic acid equivalents per g dry extract for extracts 1A, 2A and 2B, respectively, which values are again lower than values reported in literature for ethanolic extracts, as expected. Regarding the antioxidant activity the results showed that the extracts of A. cylindraceae are a possible source of natural antioxidants. According to ABTS assay, the results were: 10 ± 1 (1A); 8.4 ± 0.1 (2A); 8.3 ± 0.9 (2B) mg ascorbic acid equivalent per g dry extract. According to the results, these extracts could still be considered as a natural source of antioxidants. Thus, the valorisation of these bio-residues through the development of value- added“green” products is an opportunity to increase the sustainability of the mushroom production chain.
- Pleurotus ostreatus and Pleurotus eryngii as a source of phenolic compoundsPublication . Marçal, Sara; Vale, Pedro; Sousa, Ana Sofia; Nunes, Catarina; Barros, Joana; Ferreira, Inês; Nunes, João; Pintado, ManuelaThe intake of phenolic compounds from food products and supplements has been associated to prevention of degenerative diseases, mainly due to their antioxidant activity. The phenolic compounds can be found in plant foods and mushrooms. The main goal of this study was to quantify the total phenolic compounds of aqueous extracts from two mushrooms species, Pleurotus ostreatus and Pleurotus eryngii, and evaluate their antioxidant activity. The aqueous extracts from P. ostreatus and P. eryngii were obtained through two extraction methods (M1 and M2). In M1, a hot extraction was performed (extract M1) (90 ºC, 500 rpm, 1 h). In M2, a room temperature extraction (extract M2A), followed by a hot extraction (extract M2B) (90 ºC, 500 rpm, 1 h) of extract M2A residue, was done. Extracts M1, M2A, and M2B obtained from each mushroom species were lyophilized, and the extraction yields were determined. Total phenolics content was quantified through Folin Ciocalteu method. The results were expressed as gallic acid equivalents (GAEs). In its turn, the antioxidant activity was determined through ABTS and ORAC methods. The results of the two methods were expressed as ascorbic acid equivalents (AAEs) and trolox equivalents (TEs), respectively. The cytotoxicity (PrestoBlue) and mutagenicity (Ames) of all extracts also were evaluated.The extraction yield of extracts M1, M2A and M2B from P. ostreatus were 41.33% ± 4.29, 33.60% ± 0.39 and 15.18% ± 0.70, respectively. In its turn, the extraction yield of extracts M1, M2A, and M2B from P. eryngii were 46.03 ± 2.18, 44.46 ± 3.96, 12.58 ± 0.94. All extracts from both mushroom species were good sources of phenolic compounds. The extracts M1, M2A and M2B from P. ostreatus had 15.80 ± 1.54, 16.57 ± 0.26 and 16.65 ± 1.01 mg GAEs / g dry extract, while extracts M1, M2A and M2B from P. eryngii had 9.06 ± 0.63, 7.90 ± 0.46, 9.25 ± 0.28 mg GAEs / g dry extract. Antioxidant activity was observed in all extracts. The antioxidant activity of extracts from P. ostreatus (M1: 5.78 ± 0.31; M2A: 6.33 ± 0.83; M2B: 4.39 ± 1.12 mg AAEs / g dry extract) was higher than antioxidant activity of extracts from P. eryngii (M1: 5.48 ± 0.03; M2A: 2.23 ± 0.15; M2B: 3.87 ± 0.39 mg AAEs / g dry extract). No extract showed any genotoxic or cytotoxic effect. The results of this study indicate that aqueous extracts from P. ostreatus and P. eryngii are a source of phenolic compounds. Possibly, these extracts have the potential to be used in the development of food products and nutraceuticals enriched in phenolic compounds associated to other relevant properties ascribed to these mushrooms.
- Pleurotus ostreatus bio-residues: a source of bioactives with antioxidant and antimicrobial activityPublication . Sousa, Ana Sofia; Nunes, Catarina; Barros, Joana; Ferreira, Inês; Freitas, Ana C.; Morais, Alcina M. M. B.; Nunes, João; Pintado, ManuelaMushrooms are known to be a rich source of functional and bioactive compounds. Among these, phenolic compounds and polysaccharides, mainly β-glucans, stand out due to their antioxidant and immunomodulatory effects, respectively. In the present work, the total phenolic compounds content, the content in β-glucans and bioactivity properties from the bio-residues obtained from mushroom production were evaluated in order to develop a circular bioeconomy approach. Pleurotus ostreatus, one of the most cultivated species worldwide, was studied. The extraction was performed using water as the only solvent to obtain the possible greener process and easy to scale up at the industrial level.The aqueous extracts were obtained according to two different methods (1 and 2). In method 1, a hot extraction was performed (90 °C; 1 h; 500 rpm; extract 1A). In method 2, a room temperature extraction was carried out (extract 2A), and the resulting residue was subsequently extracted with hot water (90 °C; 1 h; 500 rpm; extract 2B). Extracts were freeze-dried, and the content of total phenolic compounds (TPC) was determined using the Folin-Ciocalteu method. β-glucans content was determined according to the "β-Glucan Assay Kit (Yeast & Mushroom)" assay. Moreover, the extracts' bioactivity was evaluated by assessing the antioxidant (ABTS, DPPH and ORAC) and antimicrobial (minimum inhibitory concentration – MIC) activities. The mutagenicity and cytotoxicity were evaluated by Ames and PrestoBlue assays, respectively. The TPC obtained was 11.94 ± 1.50, 9.95 ± 0.50 and 12.39± 0.57 mg gallic acid equivalent per g of dry extract for extracts 1A, 2A and 2B, respectively. Regarding the β-glucan content the results were: 10.67 ± 0.19 (1A), 7.62 ± 0.09 (2A), 5.96 ± 0.03 (2B) g per 100 g of dry mushroom. The extracts M2B and M1 were the ones that presented the highest results for the phenolic compounds and β-glucans, respectively. Furthermore, all extracts showed antioxidant activity (lower activity in the DPPH assay) and antimicrobial activity against the tested bacteria (Salmonella enterica, Escherichia coli, Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas tolaasii, Pseudomonas agarici, Yersinia enterocolitica, Staphylococcus aureus, Bacillus cereus e Listeria monocytogenes), with the 2A extract standing out as an inhibitor of bacterial growth. The extracts did not show mutagenicity or cytotoxicity at the tested concentrations (40 mg/mL). Thus, the aqueous extracts from P. ostreatus bio-residues could be considered a promissory natural source of bioactives, namely phenolic compounds and β-glucans with relevant biological properties. Besides, the valorisation of these bio-residues presents an opportunity to promote the mushroom production chain sustainability.
- Sustainable silk-based particulate systems for the controlled release of pharmaceuticals and bioactive agents in wound healing and skin regenerationPublication . Bernardes, Beatriz G.; Veiga, Anabela; Barros, Joana; García-González, Carlos A.; Oliveira, Ana LeiteThe increasing demand for innovative approaches in wound healing and skin regeneration has prompted extensive research into advanced biomaterials. This review focuses on showcasing the unique properties of sustainable silk-based particulate systems in promoting the controlled release of pharmaceuticals and bioactive agents in the context of wound healing and skin regeneration. Silk fibroin and sericin are derived from well-established silkworm production and constitute a unique biocompatible and biodegradable protein platform for the development of drug delivery systems. The controlled release of therapeutic compounds from silk-based particulate systems not only ensures optimal bioavailability but also addresses the challenges associated with conventional delivery methods. The multifaceted benefits of silk proteins, including their inherent biocompatibility, versatility, and sustainability, are explored in this review. Furthermore, the intricate mechanisms by which controlled drug release takes place from silk-based carriers are discussed.