ABSTRACT
myrsine coriacea (Sw.) R. Br. ex Roem. & Schult. (Primulaceae) conhecida popularmente como capororoquinha ou capororoca, é amplamente distribuída nas regiões sul e sudeste do Brasil. As espécies desse gênero apresentam um potencial antioxidante e anti-inflamatório, que pode ser acessado na busca de novos ativos para o tratamento de desordens pigmentares da pele. Desta forma, este trabalho teve como objetivos avaliar o potencial antitirosinase e antioxidante de extratos e frações de M. coriacea e identificar os possíveis compostos responsáveis por essas atividades. Foram realizados ensaios para avaliar o potencial antioxidante das amostras através do método do DPPH, enquanto a capacidade hipopigmentante das amostras foi avaliado pela inibição da enzima tirosinase. Como complemento, foram determinados os teores de compostos fenólicos totais e flavonoides através dos métodos colorimétricos empregando o reagente Folin-Ciocalteau e AlCl3. Adicionalmente, os extratos de M. coriacea tiveram avaliados seus potenciais citotóxicos utilizando diferentes linhagens tumorais humanas. O perfil fitoquímico de M. coriacea foi analisado por cromatografia a gás acoplada com espectrometria de massas (CG-EM) e cromatografia em camada delgada (CCD) com padrões. Nessas análises foram identificados 34 compostos, sendo o ácido palmítico e o palmitato de etila os compostos majoritários nas amostras de M. coriacea. O extrato bruto das folhas apresentou o maior teor de fenólicos totais, enquanto a fração de acetato de etila das folhas teve o maior teor de flavonoides. Contudo, o extrato bruto dos frutos apresentou a melhor atividade antioxidante de todas as amostras analisadas, apresentando também a melhor atividade antitirosinase. Dentre os compostos anotados, mandenol, ácido -linoleico e o linolenato de etila foram os compostos considerados como possíveis inibidores da tirosinase, com boa interação molecular com a enzima nas análises de ancoragem molecular in silico. Das amostras analisadas com relação a inibição de crescimento frente as células tumorais, a amostra da fração de clorofórmio das folhas foi a que apresentou potencial antitumoral frente as células de adenocarcinoma de cólon (HCT116)
myrsine coriacea (Sw.) R. Br. ex Roem. & Schult. (Primulaceae) popularly known as capororoquinha or capororoca, is widely distributed in southern and southeastern Brazil. Myrsine species have an antioxidant and anti-inflammatory potential, which can be accessed in the search for new actives for the treatment of skin pigmentation disorders. Thus, this work aimed to evaluate the antityrosinase and antioxidant potential from extracts and fractions of M. coriacea and to identify the probable compounds responsible for these activities. Assays were performed to evaluate the antioxidant potential of the samples using the DPPH method, while the hypopigmentation capacity of the samples was evaluated by the tyrosinase inhibition. As a complement, the amounts of total phenolic compounds and flavonoids were determined through colorimetric methods using the Folin-Ciocalteau reagent and AlCl3. Additionally, M. coriacea extracts had their cytotoxic potential evaluated using different human tumor cell lines. M. coriacea phytochemical profile was obtained by gas chromatography coupled with mass spectrometry (GC-MS) and thin layer chromatography (TLC) with standards. In these analyses, 34 compounds were identified, with palmitic acid and ethyl palmitate as the major compounds in M. coriacea samples. The leaf crude extract presented the highest total phenolics contents, while the leaf ethyl acetate fraction had the highest flavonoid amounts. However, the fruit crude extract showed the best antioxidant and antityrosinase activities of all analyzed samples. Among the annotated compounds, mandenol, -linoleic acid and ethyl linolenate were the compounds considered as putative tyrosinase inhibitors, presenting good molecular interaction with the enzyme active site in the in silico molecular docking analysis. The leaf chloroform fraction was the only sample that showed an antitumor potential against colon adenocarcinoma cells (HCT116)
Subject(s)
Monophenol Monooxygenase/analysis , Primulaceae/metabolism , Myrsine/classification , Fruit/classification , Antioxidants/analysis , Mass Spectrometry/methods , Skin Pigmentation/immunology , Chromatography, Thin Layer/methods , Hypopigmentation/pathologyABSTRACT
The genus Nothofagus is one of the most abundant in the subantarctic Patagonian forests. Five species inhabit these ecosystems, three evergreen (Nothofagus betuloides, Nothofagus dombeyi, and Nothofagus nitida) and two deciduous (Nothofagus pumilio and Nothofagus antarctica). This is the first report on the levels of secondary metabolites and the antioxidant capacity of Patagonian tree species growing in natural environments. The aim of this work was to carry out a phytochemical screening, to determine the antioxidant capacity, the sun protection factor, and the α-glucosidase and tyrosinase inhibitory activity of foliar extracts of the five previous species. Besides, Aristotelia chilensis and Berberis microphylla, two species of Patagonian shrubs growing in the same forests, were used as reference. N. dombeyi was the Nothofagus with the best antioxidant capacity. B. microphylla differed from all studied species. Moreover, the Nothofagus was split into two groups. N. betuloides and N. dombeyi are the most similar species to A. chilensis. The α-glucosidase was completely inhibited by all studied extracts. Furthermore, N. antarctica, N.pumilio, and N. nitida inhibited about 70% of the tyrosinase activity. All the results found in this study for the species of the genus Nothofagus support further research on their potential beneficial properties for human health.
Subject(s)
Antioxidants/pharmacology , Enzyme Inhibitors/pharmacology , Phytochemicals/pharmacology , Trees/chemistry , Antioxidants/chemistry , Antioxidants/metabolism , Benzothiazoles/antagonists & inhibitors , Biphenyl Compounds/antagonists & inhibitors , Chile , Drug Evaluation, Preclinical , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/metabolism , Forests , Humans , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/metabolism , Phytochemicals/chemistry , Phytochemicals/metabolism , Picrates/antagonists & inhibitors , Species Specificity , Sulfonic Acids/antagonists & inhibitors , Trees/metabolism , alpha-Glucosidases/metabolismABSTRACT
To contribute enzymatic browning inhibitors to the food industry and also extend knowledge about the phytochemical profile of the anti-tyrosinase plant Lepechinia meyenii, its ethanol extract was subjected to bioguided fractionation. Three hydroxycinnamic acids, p-coumaric acid (1), caffeic acid (2) and rosmarinic acid (3), were isolated as mainly responsible for its activity. Compounds 1, 2 and 3 showed themselves highly effective for inhibiting tyrosinase with IC50 values of 0.30, 1.50 and 4.14⯵M, respectively, for monophenolase activity and 0.62, 2.30 and 8.59⯵M, respectively for diphenolase activity. This is the first report describing the isolation of the compounds causing the tyrosinase inhibitory activity of L. meyenii extract. The inhibitory kinetics of 1-3 using both L-tyrosine and L-DOPA as substrates was investigated and the results obtained were discussed at molecular level by docking analysis. The resulting compounds 1-3 and a phenolic-enriched fraction of the extract, 2.9-fold more active than the starting material, may be suitable as non-toxic and inexpensive alternatives for the control of deleterious enzymatic darkening.
Subject(s)
Coumaric Acids/chemistry , Enzyme Inhibitors/chemistry , Lamiaceae/chemistry , Monophenol Monooxygenase/antagonists & inhibitors , Agaricales/enzymology , Catalytic Domain , Coumaric Acids/isolation & purification , Coumaric Acids/toxicity , Enzyme Assays , Enzyme Inhibitors/isolation & purification , Enzyme Inhibitors/toxicity , Humans , Kinetics , Molecular Docking Simulation , Monophenol Monooxygenase/chemistryABSTRACT
It is reported in this study the effect of isolates from leaves of Aristotelia chilensis as inhibitors of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase enzymes. The aim of the paper was to evaluate the activity of A. chilensis towards different enzymes. In addition to pure compounds, extracts rich in alkaloids and phenolics were tested. The most active F5 inhibited AChE (79.5% and 89.8% at 10.0 and 20.0 µg/mL) and against BChE (89.5% and 97.8% at 10.0 and 20.0 µg/mL), showing a strong mixed-type inhibition against AChE and BChE. F3 (a mixture of flavonoids and phenolics acids), showed IC50 of 90.7 and 59.6 µg/mL of inhibitory activity against AChE and BChE, inhibiting the acetylcholinesterase competitively. Additionally, F3 showed and high potency as tyrosinase inhibitor with IC50 at 8.4 µg/mL. Sample F4 (anthocyanidins and phenolic composition) presented a complex, mixed-type inhibition of tyrosinase with a IC50 of 39.8 µg/mL. The findings in this investigation show that this natural resource has a strong potential for future research in the search of new phytotherapeutic treatments for cholinergic deterioration ailments avoiding the side effects of synthetic drugs. This is the first report as cholinesterases and tyrosinase inhibitors of alkaloids and phenolics from A. chilensis leaves.