288 research outputs found
Actividad antihipóxica y actividad antioxidante de semilas de Hibiscus esculentus
The antihypoxic and antioxidant activities of Hibiscus esculentus seeds were investigated employing eight in vitro assay systems. Antihypoxic activity was investigated in two models, haemic and circulatory. The effects were pronounced in both models of hypoxia. The antihypoxic effects were dose-dependent. The results indicated that the extracts have a protective effect against hypoxia induced lethality in mice. The extracts showed antioxidant activity in some models. IC50 for DPPH radical-scavenging activity was 234 ± 8.9 μg ml-1. The extracts showed weak nitric oxide-scavenging activity between 0.1 and 1.6 mg ml-1. The extracts showed weak Fe2+ chelating ability. IC50 were 150 ± 13 μg ml-1. The extracts also exhibited low antioxidant activity in the linoleic acid model but were capable of scavenging hydrogen peroxide in a concentration dependent manner. The total amount of phenolic compounds in each extract was determined as gallic acid equivalents and total flavonoid contents were calculated as quercetin equivalents from a calibration curve. Pharmacological effects may be attributed, at least in part, to the presence of phenols and flavonoids in the extracts.La actividad antihipóxica y antioxidante de semillas de Hibiscus esculentus fue investigada empleando ocho ensayos in vitro. La actividad antihipóxica fue investigada en dos modelos, uno de caracter hemínico y otro circulatorio. Los efectos fueron pronunciados en ambos modelos de hipoxia. Los efectos antihipóxicos fueron dependientes de la dosis. Los resultados indican que los extractos tienen un efecto protector contra la letabilidad inducida por hipoxia en ratones. Los extractos mostraron actividad antioxidante en algunos modelos. El IC50 para la actividad captadora de radicales fue 234 ± 8.9 μg ml-1. Los extractos muestran una débil actividad captadora de óxido nítrico comprendida entre 0.1 y 1.6 mg ml-1. Los extractos muestran una débil capacidad quelatante de Fe2+. El IC50 fue de 150 ± 13 μg ml-1. Los extractos también muestran una baja actividad antioxidante en modelos con ácido linoleico aunque fueron capaces de eliminar peróxido de hidrógeno en una manera dependiente de la concentración. La concentración de compuestos fenólicos totales en cada extracto fue determinado como equivalents de ácido gálico y el contenido total de flavonoides fue calculado como equivalentes de quercitina para la curva de calibración. Los efectos farmacológicos pueden ser atribuidos, al menos en parte, a la presencia de fenoles y flavonoides en el extracto
The antioxidant activity of wild medlar (Mespilus germanica L.) fruit, stem bark and leaf
The medlar is an edible fruit. Modern medicine has recognized its healing properties in the treatment of some diseases. There is no scientific data in the literature about the antioxidant activity of methanol or aqueous extract of medlar fruit, leaf or stem bark. Antioxidant activities of these parts were evaluated by employing six test systems. Stem bark extract (aqueous and methanol) showed best activity in 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity with IC50 = 10.7 ± 0.6 and 11.4 ± 0.8 μgml-1, respectively. All extracts showed weak Fe2+ chelating ability. Methanol extract of fruit had better activity in nitric oxide scavenging model than others (IC50 = 247 ± 12.2 μgml-1). The leaves and bark extracts showed good reducing power than fruit extract. In reducing powers, there were no significant differences (p > 0.05) among the stem bark and leaves extracts that were comparable with vitamin C (p< 0.05). Extracts exhibited good antioxidant activity in the ferric thiocyanate (FTC) method. They manifested almost the same pattern of activity as vitamin C and butylated hydroxyanisole (BHA) at different incubation times (until 72nd hour) but stem bark extract showed higher peroxidation inhibition than vitamin C and BHA at the 96th hour (p < 0.05). The extracts were capable of scavenging H2O2 in a concentration-dependent manner. Leaves methanol extract showed good activity that was comparable with quercetin (p > 0.05). Bark and leaf extracts had higher total phenolic and flavonoid contents than fruit.Keywords: Antioxidant activity, free radical scavenging, Mespilus germanica, medlar, phenolic contents, flavonoids content
Angular right symmetricity of bounded linear operators on Hilbert spaces
We introduce and characterize angular right symmetric and approximate angular right symmetric points of the algebra of all bounded linear operators defined on either real or complex Hilbert spaces
Antioxidant activity of different parts of Tetrataenium lasiopetalum.
In Iranian traditional medicine, different species of the genus Tetrataenium are used as antiseptic, spice and food additives.The present study examined the possible antioxidant effects of hydro-alcoholic extracts of different parts of Tetrataenium lasiopetalum (Boiss.) Manden (Apiaceae).Laminas, stems, petioles, fruits, peduncles and flowers of T. lasiopetalum were collected, dried and then extracted by ethanol and water (70:30). Antioxidant activities of extracts were examined by employing different in vitro assays, i.e., 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating, reducing power activities and hemoglobin-induced linoleic acid system. Also, total phenolic and flavonoid contents of the extracts were evaluated.Hydro-alcoholic extract of T. lasiopetalum flower showed the highest activity in scavenging of DPPH (IC50 = 170 ± 7 μg/mL). In metal chelating assay, lamina extract possesses a better iron ion chelating activity than other extracts (230 ± 10 μg/mL). Lamina hydro-alcoholic extract demonstrated better activity in reducing the power and hemoglobin-induced linoleic acid system than other parts of T. lasiopetalum.These results showed the antioxidant activity of different parts of T. lasiopetalum based on its usage in traditional medicine
Actividad antioxidante de extractos metanólicos de Ferula assafoetida y la composición de su aceite esencial
The antioxidant activity of the aerial parts of Ferula assafoetida was determined by employing various in vitro assay systems. IC50 for DPPH radical-scavenging activity was 380 ± 12 mg ml-1. The extracts showed good nitric oxide-scavenging activity (IC50 was 270 ± 3) and Fe2+ chelating ability (IC50 was 0.57 ± 0.02 mg ml-1). The peroxidation inhibition (antioxidant activity) of the extracts exhibited values from 82% (at 24 hrs) and 88% (at 72 hrs). The extract exhibited a fairy weak reducing power at 25-800 μg ml-1 of extracts which was not comparable with Vitamin C (p < 0.001). The tested extracts exhibited very low antioxidant activity. In addition, the chemical composition of the essential oil of the aerial parts was determined. The major compounds were phenol, 2-methyl-5-(1-methyl ethyl) (18.2 %), α.-Bisabolol (10.4%) and Arsine triethyl (8.7 %). Total phenol compounds, as determined by the Folin Ciocalteu method, were 94.8 ± 5.9 mg gallic acid equivalent/g of extract powder and the total flavonoid content (by AlCl3 method) was 90.9 ± 6.3 mg quercetin equivalent/g of extract powder.La actividad antioxidante de las partes aéreas de Ferula assafoetida se determinó empleando varios sistemas de ensayos in vitro. El IC50 de la actividad captadora de radicales de DPPH fue 380 ± 12 mg ml-1. Los extractos también mostraron una buena actividad captadora de óxido nítrico (IC50 fue 270 ± 3) y capacidad quelatante de Fe2+ (IC50 fue 0.57 ± 0.02 mg ml-1). La inhibición de la peroxidación (actividad antioxidante) de los extractos mostró valores del 82% (a las 24 horas) y 88% (a las 72 horas). El extracto mostró un ligero descenso del poder reductor con 25- 800 μg ml-1 de extracto que no fue comparable con la vitamina C (p < 0.001). Los extractos ensayados mostraron una muy baja actividad antioxidante. Además, la composición química del aceite esencial de las partes aéreas fue determinada. Los principales compuestos fueron fenol, 2-metil-5-(1-metil etilo) (18.2 %), α.-Bisabolol (10.4%) and Arsine trietilo (8.7 %). Los fenoles totales, determinados por el método de Folin-Ciocalteau, fue de 94.8 ± 5.9 mg de equivalentes de ácido gálico/g de extracto en polvo y el contenido total de flavonoides (por el método del AlCl3) fue de 90.9 ± 6.3 mg de equivalentes de quercitina/g de extracto en polvo
Oleuropein and Cancer Chemoprevention: the Link is Hot
Cancer comprises a collection of related diseases characterized by the existence of altered cellular pathways resulting in an abnormal tendency for uncontrolled growth. A broad spectrum, coordinated, and personalized approach focused on targeting diverse oncogenic pathways with low toxicity and economic natural compounds can provide a real benefit as a chemopreventive and/or treatment of this complex disease. Oleuropein, a bioactive phenolic compound mainly present in olive oil and other natural sources, has been reported to modulate several oncogenic signalling pathways. This review presents and critically discusses the available literature about the anticancer and onco-suppressive activity of oleuropein and the underlying molecular mechanisms implicated in the anticarcinogenic and therapeutic effects. The existence of limitations and the promising perspectives of research on this phenolic compound are also critically analyzed and discussed.This article is the outcome of an in-house financially non-supported study. A. Sureda was
partially supported by the Spanish Ministry of Health, Social Services and Equality (CIBEROBN-B12/03/30038).
A. Mocan acknowledges funding from UEFISCDI, Romania, project no. PNII-RU-TE-2014-4-1247.info:eu-repo/semantics/publishedVersio
HE IMPACT OF ACCOUNTANTS’ ETHICAL APPROACHES ON THE DISCLOSURE QUALITY OF CORPORATE SOCIAL RESPONSIBILITY INFORMATION AN ISLAMIC PERSPECTIVE IN IRAN
Abstract. The focus of business units on maximizing profits, tackling competitive challenges, emphasizing short-term outcomes, and delivering diverse accounting services has put accountants in a climate of conflict and pressure that has led to unethical outcomes for them. Accounting plays a key role in the social and economic progress of a nation. Ethical standards are a hallmark of the accounting profession. The key question is how the ethical approaches of accountants have an impact on the disclosure quality of corporate social responsibility information. The main purpose of this study is to test a modified Multidimensional Ethics Scale (MES) to measure the ethical evaluations of accountants and financial managers todetermine the effects Accountants’ Ethical Decision Making on the CSR. Overall, The results show that there is a positive and significant relationship between the ethical approaches of accountants and the quality of disclosure of accounting information.Keywords: Ethics, Multi dimensional, Ethics Scale, CSR, ICSR
Monsoon effects on the copepod community structure in the Chabahar Bay, Oman Sea
Calanoid, cyclopoid, harpacticoid and poecilostomatoid copepods were investigated over the year at five stations in the Chabahar Bay, Oman Sea. This area is under the influence of the Indian Ocean seasonal monsoons. The samples were collected using vertical plankton tows with 100 µm mesh nets. Copepods were identified into 20 genera and 59 species. Calanoid formed about 15% to 62% and cyclopoid 26% to 39% of total copepod abundance. Harpacticoid constituted about 6% in South West (SW)-monsoon and flourished well in pre (SW)-monsoon, formed 46% of copepod abundance. Poecilostomatoid accounted for approximately 5% to 13% of the total copepods. The most dominant species were Temora turbinata, Paracalanus elegans, Oithona nana and Euterpina acutifrons. The results showed that the species composition and distribution of copepods differed between the monsoon seasons, due to changes in hydrographic conditions. Furthermore, high abundance of small-sized copepods observed in offshore stations
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