Changes in the constituents and UV-photoprotective activity of Astragalus membranaceus caused by roasting / 한국영양학회지

PURPOSE: Astragalus membranaceus (AM) is an important traditional medicinal herb. Pharmacological research has indicated that AM has various physiological activities such as antioxidant, anti-inflammatory, immunoregulatory, anticancer, hypolipidemic, antihyperglycemic, and hepatoprotective activities. The bioactive substances responsible for the physiological activities in AM, including many antioxidant substances, change during the roasting process. This study investigated and compared the changes in the antioxidant constituents of AM caused by roasting. METHODS: DPPH (1,1-diphenyl-2-picryl hydrazyl) and ABTS⁺ (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) radical scavenging activities and their total phenolic content (TPC) were measured. High-performance liquid chromatography (HPLC) analysis was performed to confirm any changes in the isoflavonoids of roasted AM (R-AM),. The cell viability of UVB-induced HDF (Human dermal fibroblast) cells treated with AM and R-AM extracts was investigated. The comet assay was used to examine the inhibitory effects of R-AM extracts on DNA damage caused by oxidative stress. RESULTS: The DPPH and ABTS⁺ radical scavenging activities were 564.6±20.9 and 108.2±3.1 (IC₅₀ value) respectively, from the 2R-AM. The total phenol content was 47.80±1.40 mg GAE/g from the 1R-AM. The values of calycosin and formononetin, which are the known isoflavonoid constituents of AM, were 778.58±2.72 and 726.80±3.45 µg/g respectively, from the 2R-AM. Treatment of the HDF cells with R-AM (50 ~ 200 µg/mL) did not affect the cell viability. Furthermore, the R-AM extracts effectively protected against UVB-induced DNA damage. CONCLUSION: The findings of this study indicate that R-AM increases its isoflavonoid constituents and protects against UVB-induced DNA damage in HDF cells.

Análise fitoquímica e atividade fotoprotetora de extrato etanólico de Euphorbia tirucalli Linneau (Euphorbiaceae) / Phytochemical analysis and photoprotective activity of theethanolic extract of Euphorbia tirucalli Linneau (Euphorbiaceae)

RESUMO Euphorbia tirucalli Linneau, conhecida popularmente como "avelós", "cachorro pelado" ou "pau-pelado", é utilizada na medicina popular para o tratamento de câncer, antibiótico e antivirótico. As plantas medicinais são, frequentemente, utilizadas com o intuito de substituir ou auxiliar as terapias convencionais no tratamento de várias doenças, inclusive para evitar os malefícios causados por radiações ultravioletas. Com isso, o objetivo desta pesquisa foi avaliar o potencial fotoprotetor e a triagem fitoquímica do extrato etanólico das partes aéreas de avelós. A atividade fotoprotetora foi avaliada por meio de ensaios in vitro segundo o método adaptado de Mansur, utilizando extrato etanólico das partes aéreas. Os resultados obtidos mostraram que o estudo fitoquímico evidenciou a presença de açúcares redutores, alcaloides, fenóis, flavonoides, taninos, saponinas, esteroides e triterpenóides na fração etanólica. O extrato apresentou capacidade antioxidante (EC50) de 16,98 ± 0,35 µg.mL-1, teor de compostos fenólicos de 96,18 ± 1,33 mg EqAG/g e flavonoides de 63,57 ± 2,74 mg EqC/g que podem favorecer a atividade fotoprotetora. Avaliando o fator de proteção solar, pode-se observar que todas as concentrações testadas (0,01 a 0,1 µg.mL-1) apresentaram potencial de fotoproteção da radiação ultravioleta com variação de FPS de 6,05 a 19,84, respectivamente. Esses resultados sugerem que o extrato etanólico de Euphorbia tirucalli Linneau apresenta possível efeito fotoprotetor

ABSTRACT Euphorbia tirucalli Linneau, popularly known as "avelos", "naked cock" or "naked dog", is used in popular medicinein order to treat cancer, antibiotic and antiviral diseases. Herbal medicines are often employed in order to assist or replace conventional therapies for the treatment of several diseases, including the prevention of the damage caused by ultraviolet radiation. Thus, the aim of this research was to evaluate the photoprotective potential and phytochemical screening of the ethanol extract of the aerial parts of avelos. The photoprotective activity was assessed by in vitrotrials according to the method adapted from Mansur, using the ethanol extract of the aerial parts. The results showed that the phytochemical study revealed the presence of reducing sugars, alkaloids, phenols, flavonoids, tannins, saponins, steroids and triterpenoids in ethanolic fraction. The extract showed antioxidant activity (EC50) of 16,98 ± 0,35 µg.mL-1, phenolic contents of 96,18 ± 1,33 mg EqAG/g and 63,57 ± 2,74 flavonoids from mg EqC/g that can advantage the photoprotective activity. Assessing the sun protection factor, it can be observed that all the tested concentrations (0,01 to 0,1 µg.mL-1) showed potential for photoprotection from ultraviolet radiation with a range of 6,05 to 19,84 FPS, respectively. These results suggest that the ethanol extract of Euphorbia tirucalli Linneau presents possible photoprotective effect

In vitro antioxidant and photoprotective activities of dried extracts from Neoglaziovia variegata (Bromeliaceae).

The phytochemical screening, antioxidant and photoprotective activities of dried extracts from the leaves of Neoglaziovia variegata were investigated. It was also evaluated the total phenolic and flavonoid contents by the Folin-Ciocalteu and aluminum chloride methods, respectively. Antioxidant activities of the extracts were evaluated by using of 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging and β-carotene-linoleic acid bleaching and compared with ascorbic acid, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) used as reference compounds. The photoprotective effect was evaluated by the spectrophotometric method. Preliminary analysis demonstrated that the extracts were found to be positive for the presence of anthracene derivatives, flavonoids, tannins, mono and diterpenes, naphthoquinones, coumarins, triterpenoids and steroids. The most significant total phenolic and flavonoid contents was of 608.50 ± 14.74 mg of gallic acid equivalent/g and 272.50 ± 9.25 mg of catechin equivalent/g, respectively, for ethyl acetate fraction (Nv-AcOEt). The Nv-AcOEt also presented the best antioxidant activity (IC50 3.51 ± 0.18 μg/ml) for DPPH scavenging. The chloroform fraction (Nv-CHCl3) and Nv-AcOEt showed characteristic absorption bands in regions UVB and UVA in a concentration-dependent manner. Nv-AcOEt presented the highest sun protection factor SPF (27. 68 ± 4.03). It shows the possibility to use this extract as sunscreen in pharmaceutical preparations.