Loading...
3 results
Search Results
Now showing 1 - 3 of 3
- 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.
- Utilização de folhas de v. Vinífera fermentadas como conservante em iogurte com polpa de morangoPublication . Freitas, Lais; Estevinho, Leticia M.; Paula, Marina BrancoA fermentação é um dos métodos mais tradicionais utilizados na preservação dos alimentos, pois a condução controlada de microrganismos específicos pode contribuir para o aumento da vida de prateleira dos alimentos. O iogurte é um produto obtido a partir da fermentação láctica conduzida por bactérias termofílicas Lactobacillus delbrueckii subsp. bulgaricus e do Streptococcus salivarius subsp thermophilus, provocando a redução do pH do leite, obtendo a formação de coágulos. Esses microrganismos possuem atividades específicas que contribuem nas características específicas do produto final, como cor, odor, aspecto e sabor. Além da fermentação, outro método utilizado na preservação dos alimentos é a aplicação de aditivos químicos, que podem gerar possíveis efeitos negativos à saúde dos consumidores. Devido à conscientização do consumidor sobre esses riscos, o uso dos conservantes sintéticos têm vindo a diminuir, dando assim preferência aos conservantes naturais.
- Fermented Grapevine Leaves: Potential Preserving Agent in YogurtPublication . Freitas, Lais; Sousa-Dias, Miguel L.; Paula, Vanessa B.; Dias, L.G.; Estevinho, Leticia M.In this study, we monitored the fermentative process of Vitis vinifera L. leaves (grapevine), spontaneously or promoted by Saccharomyces cerevisiae, in both solid and liquid media. We also aimed to evaluate the effect on the bioactivity and shelf life of yogurt incorporating fermented and non-fermented grapevine leaves compared to yogurt produced with the preservative potassium sorbate. The results revealed that fermented grapevine leaf extracts increased their bioactive compounds and antioxidant activity, particularly in fermentations in a solid medium. In yogurt samples with incorporation extract from solid spontaneous fermentation and extract from solid yeast fermentation, even in small quantities, they exhibited higher levels of total phenols (1.94 and 2.16 mg GAE/g of yogurt, respectively) and antioxidant activity (5.30 and 5.77 mg TroloxE/g of yogurt; and 1.33 and 1.34 mg Fe(II)E/g of yogurt, respectively) compared to control yogurt (1.44 mg GAE/g of yogurt, 4.00 mg TroloxE/g of yogurt, and 1.01 mg Fe(II)E/g of yogurt). Additionally, yogurts supplemented with fermented grapevine leaves demonstrated the potential to inhibit microbial growth without impairing the multiplication of lactic acid bacteria.