Percorrer por autor "Costa, Maria Angélica Carvalho"
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- Antioxidant, photoprotective and inhibitory activity of tyrosinase in extracts of Dalbergia ecastaphyllumPublication . Morais, Daniel Vieira; Costa, Maria Angélica Carvalho; Bárbara, Marivalda; Silva, Fabiane de Lima; Moreira, Manuela M.; Delerue-Matos, Cristina; Dias, L.G.; Estevinho, Leticia M.; Carvalho, Carlos Alfredo Lopes deDalbergia ecastaphyllum is a native Brazil plant with importance for beekeeping, and widely used in folk medicine. For the first time, the extracts of this plant were assessed for the presence of hydrophilic and lipophilic antioxidants, as well as inhibition of tyrosinase, free radicals scavenging and sunscreen protection. The antioxidant activity was evaluated by free radical scavenging (DPPH) andβ-carotene bleaching assay. The tyrosinase inhibitory activity was evaluated and calculated the EC50. The photoprotective activity was measured using different concentrations of D. ecastaphyllum extracts. The Sun Protection Factor (SPF) of the samples was higher than 6, and the sample from Ilhe ´us showed the most pronounced photoprotective effect. Sample from Canavieiras presented the highest antioxidant activity by free radical scavenging DPPH andβ-carotene bleaching method, with 92.41% and 48.34%, respectively. All samples inhibited the tyrosinase, especially the sample from Prado that was most effective (124.62μg.mL-1). Significant negative correlation was found between flavonoid contents and inhibition of tyrosinase. The overall results provide relevant information about the Dalbergia ecastaphyllum species, indicating as potential material to cosmetic and pharmaceutical industry.
- Chemical composition and biological activities of mono- and heterofloral bee pollen of different geographical originsPublication . Araújo, Jucilene; Chambó, Emerson Dechechi; Costa, Maria Angélica Carvalho; Silva, Samira Maria Peixoto Cavalcante; Carvalho, Carlos Alfredo Lopes de; Estevinho, Leticia M.Recent research shows variations in pollen chemical constituents and, consequently, in their therapeutic properties. Mono and multifloral bee pollen extracts were investigated for antioxidant and enzyme inhibitory activity properties, phenolic compounds and fatty acid composition. Generally, Eucalyptus spp. and multifloral extracts exhibited potent inhibitory activity against -amylase, acetylcholinesterase, tyrosinase, lipoxygenase, lipase and hyaluronidase. On the other hand, Miconia spp. demonstrated higher antihemolytic activity. Cocos nucifera and Miconia spp. extracts exhibited important antioxidant properties in the different assays (ABTS, DPPH, -carotene/linoleic acid and reducing power). Moreover, these extracts had greater amounts of total phenols and flavonoids in comparison to others. The increase in antioxidant activity (decrease in EC50 values) was accompanied by an increase in the amount of total phenols in the extracts. The pollen extracts contained linoleic acid and -linolenic acid as major fatty acids, followed by palmitic acid, and oleic acid. In this study, differences were observed in both chemical constituents and biological activities of the samples related to the geographical and botanical origin of bee pollen.
- Dalbergia ecastaphyllum leaf extracts: in vitro inhibitory against enzymes related to metabolic syndrome, inflammation and neurodegenerative diseasesPublication . Morais, Daniel Vieira; Moreira, Manuela M.; Silva, Fabiane de Lima; Costa, Maria Angélica Carvalho; Delerue-Matos, Cristina; Carvalho, Carlos Alfredo Lopes de; Estevinho, Leticia M.For the first time, the anti-hemolytic activity and the enzyme inhibitory activities of Dalbergia ecastaphyllum leaves extracts were tested against α-amylase, α-glucosidase, lipase, acetylcholinesterase, butyrylcholinesterase, tyrosinase and hyaluronidase. The phenolic profile of the obtained extracts was also investigated by high-performance liquid chromatography with photodiode array detection (HPLC-PAD). The extracts showed inhibitory activity against all enzymes evaluated, with the highest inhibitory activity reported for the enzyme hyaluronidase (28.28 ± 2.43 to 72.19 ± 1.40 μg mL-1). The obtained extracts also demonstrate anti-hemolytic activity (52.22 ± 1.62 to 71.17 ± 1.82%). Among the phenolic compounds identified, protocatechuic, vanillic and β-resorcylic acids were the most abundant (1.13 ± 0.06 to 2.53 ± 0.06, 0.90 ± 0.06 to 2.19 ± 0.06 and 1.03 ± 1.62 to 22.11 ± 1.62 mg L-1, respectively). In the statistical analysis, a significant correlation was found between the flavonoids content and all enzymes inhibitory activities. The present study showed that D. ecastaphyllum leaves extracts may have the potential to be used in the therapeutic treatment of several diseases such as Alzheimer, Parkinson, type 2 diabetes mellitus, hyperglycemia, and pigmentation, as well as those associated with oxidative stress.
- Phytochemical study and antioxidant activity of Dalbergia ecastaphyllumPublication . Lucas, Cátia Ionara Santos; Ferreira, Adailton Freitas; Costa, Maria Angélica Carvalho; Silva, Fabiane de Lima; Estevinho, Leticia M.; Carvalho, Carlos Alfredo Lopes deThe chemical profile of Dalbergia ecastaphyllum has been indicated as the botanical origin of Brazilian red propolis, an apicultural product with proven therapeutic properties. However, few studies have investigated this plant species. This study evaluated and compared microbiological quality, chemical composition, and antioxidant activity of stem and leaf samples of D. ecastaphyllum. The samples were collected in February 2015, in the southern region of the state of Bahia, Brazil. We performed the microbiological analyses, determined the contents of fatty acid, total phenol and flavonoid, and identified the chemical profile and antioxidant activit. Escherichia coli, Salmonella spp. and sulfite reducing clostridial spores were not detected in the samples. Acids of the family ω3 were recorded in the stems and ω6 in the leaves. The leaves presented better nutritional quality of the fraction, better antioxidant capacity in the tests by the DPPH method and β-carotene bleaching. There were 49 chemical compounds, of which 38 belonged to the class of flavonoids. The results indicate that stems and leaves of D. ecastaphyllum have biological properties. Leaves particularly are better for functional food formulation and as natural antioxidant.