Phytochemical composition and biological screening of two Lophophytum species / Composición fitoquímica y cribado biológico de dos especies de Lophophytum

Lophophytum species are holoparasites that grow on tree roots. The objectives of the work were to explore the chemical composition of the tubers of two Lophophytum species and to analyze the antioxidant, anti-inflammatory and antilithiatic activity of their extracts using in vitro methods. The chemical composition was determined by histochemical, phytochemical and TLC tests. In addition, the profile of phenolic compounds was determined by HPLC-MS. The presence of secondary metabolites of recognized activity was demonstrated. The results of the HPLC-MS/MS allowed the tentative identification of catechin, luteolin and glycosides of eriodictyol, naringenin and luteolin in the extract of Lophophytum leandriand eriodictyol, naringenin, luteolin and their glycosylated derivatives in Lophophytum mirabile. The extracts showed promising antioxidant (DPPH, ABTS and ß-carotene-linoleic acid), anti-inflammatory (inhibition of 5-LOX) and anti-urolytic (by bioautographic TLC) activity. It is noteworthy that these are the first results of the phytochemical composition and biological activity of L. mirabile. However, in vivo studies are required to corroborate these activities.

Las especies de Lophophytumson holoparásitas que crecen en raíces de árboles. Los objetivos del trabajo fueron explorar la composición química del túber de dos especies de Lophophytum y analizar la actividad antioxidante, antiinflamatoria y antilitiásica de sus extractos usando métodos in vitro. La composición química se determinó mediante pruebas histoquímicas, fitoquímicas y por TLC. Además, se determinó el perfil de compuestos fenólicos por HPLC-MS/MS. Se demostró presencia de metabolitos secundarios de reconocida actividad. Los resultados del HPLC-MS/MS permitieron identificar tentativamente catequina, luteolina y glucósidos de eriodictiol, naringenina y luteolina en el extracto de Lophophytum leandriy eriodictiol, naringenina, luteolina y sus derivados glicosilados en Lophophytum mirabile. Los extractos mostraron prometedora actividad antioxidante (DPPH, ABTS y ß-caroteno-ácido linoleico), antiinflammatoria (inhibición de la 5-LOX) y antiurolitiásica (por TLC bioautográfica). Es de destacar que estos son los primeros resultados de composición fitoquímica y actividad biológica de L. mirabile. Sin embargo, se requieren estudios in vivo para corroborar dichas actividades.

Modulatory effect of baicalein on gene expression and activity of antioxidant enzymes in streptozotocin-nicotinamide induced diabetic rats

Oxidative stress plays the central role in the pathogenesis and progression of diabetic complications. The present study aims to investigate the beneficial effect of oral administration of flavone baicalein in streptozotocin-nicotinamide (STZ-NA) induced diabetic rats by measuring oxidative stress markers, antioxidant enzyme activities and expression analysis of antioxidant genes. Experimental diabetes was induced by a single intraperitoneal (i.p.) injection of STZ (55 mg /kg b.wt), 15 min after the i.p. administration of NA. At the end of the experimental period, thiobarbituric acid reactive substances (TBARS), activities of antioxidant enzymes and expression levels of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GPx) were measured in diabetic rats along with serum biochemical parameters namely total cholesterol (TC), total triglyceride (TG), aspartate transaminase (AST) alanine transaminase (ALT) and glycosylated hemoglobin (HbA1c). Oral administration of baicalein (40 mg/kg b.wt/day) demonstrated a significant ameliorative effect on all studied biochemical and oxidative stress parameters. Biochemical findings were corroborated by qPCR expression analysis which showed significant upregulation of antioxidant genes in diabetic rats. These results suggest that baicalein supplementation may reduce diabetes and its complications by suppressing oxidative stress and enhancing gene expression and antioxidant enzyme activities in diabetic rats.

Phytochemical analysis of hydroethanolic extract of Turnera diffusa Willd and evaluation of its effects on astrocyte cell death / Análise fitoquímica do extrato hidroetanólico de Turnera diffusa Willd e avaliação de seus efeitos na morte de astrócitos

ABSTRACT Objective To evaluate the phytochemical composition of hydroethanolic extracts from powdered aerial parts of Turnera diffusa Willd (Turneraceae; T. diffusa), as well as its toxicity in astrocytes. Methods Chemical analyses of hydroethanolic extract from powdered aerial parts ofT. diffusa were carried out using HPLC-DAD-ESI-MS/MS.In vitro assays using astrocytes culture were performed to evaluate cell death. Results Flavone-C, O-diglycosides, such as, luteolin-8-C-[6-deoxy-2-O-rhamnosyl]-xylo-hexos-3-uloside, apigenin-8-C-[6-deoxy-2-O-rhamnosyl]-xylo-hexos-3-uloside and apigenin-7-O-6”-p-coumaroylglucoside were the main compounds found in this hydroethanolic extract. Concentration time-effect demonstrated the toxicity of this extract at a concentration of 1,000µg/mL in astrocyte culture, after 6 and 24 hours of incubation. Conclusion In phytochemical analyses, important antioxidants (mainly flavonoids) were observed. T. diffusa extracts presented cytotoxic effect in high concentrations, leading to increased cell death in astrocyte culture.

RESUMO Objetivo Avaliar a composição fitoquímica do extrato hidroetanólico das partes aéreas de Turnera diffusa Willd (Turneraceae; T. diffusa) e sua toxicidade em astrócitos. Métodos Análises químicas do extrato hidroetanólico de partes aéreas de T. diffusa foram feitas por HPLC-DAD-ESI-MS/MS. Os ensaiosin vitro utilizaram culturas de astrócitos para avaliar morte celular. Resultados Flavonas-C, O-diglicosídeos, como, luteolina-8-C-[6-deoxi-2-O-raminosil]-xilo-hexos-3-ulosideo, apigenina-8-C-[6-deoxi-2-O-raminosil]-xilo-hexos-3-ulosideo e apigenina-7-O-6”-p-cumaroilglucosídeo foram os principais constituintes encontrados neste extrato hidroetanólico. Uma curva tempo-concentração demonstrou toxicidade desse extrato na concentração de 1.000µg/mL, na cultura de astrócitos após 6 e 24 horas de incubação. Conclusão Nas análises fitoquímicas, importantes antioxidantes, sobretudo flavonoides, foram observados. Extratos de T. diffusa apresentaram efeitos citotóxicos em altas concentrações, ocasionando aumento de morte celular em cultura de astrócitos.

13C NMR spectral data and molecular descriptors to predict the antioxidant activity of flavonoids / Dados espectrais de RMN 13C e descritores moleculares para prever a atividade antioxidante dos flavonóides

Tissue damage due to oxidative stress is directly linked to development of many, if not all, human morbidity factors and chronic diseases. In this context, the search for dietary natural occurring molecules with antioxidant activity, such as flavonoids, has become essential. In this study, we investigated a set of 41 flavonoids (23 flavones and 18 flavonols) analyzing their structures and biological antioxidant activity. The experimental data were submitted to a QSAR (quantitative structure-activity relationships) study. NMR 13C data were used to perform a Kohonen self-organizing map study, analyzing the weight that each carbon has in the activity. Additionally, we performed MLR (multilinear regression) using GA (genetic algorithms) and molecular descriptors to analyze the role that specific carbons and substitutions play in the activity.

Danos aos tecidos devido ao estresse oxidativo estão diretamente ligados ao desenvolvimento de muitos, senão todos, os fatores de sedentarismo e de doenças crônicas. Neste contexto, a busca de moléculas naturais, que participam da nossa dieta e que possuam atividade antioxidante, flavonóides, torna-se de grande interesse. Neste estudo, nós investigamos um conjunto de 41 flavonóides (23 flavonas e 18 flavonóis), relacionando suas estruturas e atividade antioxidante. Os dados experimentais foram submetidos à análise de QSAR (relações quantitativas estrutura-atividade). Dados de RMN 13C foram utilizados para realizar um estudo do mapa auto-organizável de Kohonen, analisando o peso que cada carbono tem na atividade. Além disso, realizamos uma MLR (regressão múltipla) usando GA (algoritmos genéticos) e descritores moleculares para avaliar a influência de carbonos e substituições na atividade.

pharmacognostical study of the Rhizomes and roots of Iris florentina L. cultivated in Egypt [part I]

Four isoflavonoids were isolated from the rhizomes and roots of Iris florentina L. and identified as irisflorentin [1], irisolone [2], irigenin [3], which were previously isolated from the plant [1] and 5-hydroxy, 8,4'-dimethoxy 7-0-isoflavone glucoside [4] isolated for the first time from I. florentina. Macro- and micromorphological characters of the rhizomes and roots were also studied in order to establish its diagnostic features in both entire and powdered forms

Phytochemical investigation of sonchus oleraceus l growing in Egypt

The preliminary phytochemical screening and proximate analysis of Sonchus oleraceus L. [Asteraceae family] were presented. The methanolic extract of the herb was successively extracted with light- petroleum, chloroform, ethyl acetate and n-butanol. Lipoidal contents were detected in the light-petroleum and chloroformic extracts, while flavonoids were found in the ethyl acetate and n-butanol extracts. GLC investigation of fatty acid methyl esters of the saponifiable fraction of the light-petroleum extract revealed the presence of palmitic, linoleic and linolenic acids as the major components. Beta- sitosterol, cholesterol, beta-amyrin and taraxasterol in addition to a series of hydrocarbons [n-Cl7-n-C30] were isolated and /or identified in the unsaponifiable fraction. The pentacyclic triterpene, friedelane-3, 21-dione, 25-o1 was isolated and identified in the chloroform extract. The percentage of total flavonoids determined by complexation with aluminum chloride was 0.1% w/w. Three flavonoid glycosides viz. Luteolin-7-O glucoside, apigenin7-0-glucuronide and quercetrin were isolated and identified in the combined ethyl acetate and n-butanol extracts

Trifolexin: a new flavanonol derivative from trifolium alexandrinum seeds

Quercetin, quercetrin and the new flavanonol derivative, 6-hydroxymethyl-2R, 3R-trans-dihydroquercetin [trifolexin] were isolated from the seeds of Trifolium alex and rinum L. The chemical identities of these compounds were established by spectroscopic methods

Identificaçäo cromatográfica de flavonóides contidos em drágeas / Chromatographic identification of flavonoids in coated tablets

Os flavonóides Rutina e Hesperidina foram isolados e identificados em drágeas que os continham por cromatografia em camada delgada