Amadou Dicko

Chlorogenic acid, a polyphenol from Prunus domestica (Mirabelle), with coupled anxiolytic and antioxidant effects

BACKGROUND Oxidative stress is linked to neurodegenerative diseases, cancer, cardiovascular diseases and to some behaviors, such as anxiety and depression. In particular, recent research observed a close relationship between oxidative stress and anxiety. METHODS We investigated the anxiolytic effect of chlorogenic acid, a dietary antioxidant present in fruits, in mouse models of anxiety including the light/dark test, the elevated plus maze and the free exploratory test. Moreover, the antioxidative effect of chlorogenic acid on peripheral blood granulocytes was investigated. RESULTS Chlorogenic acid (20 mg/kg) induced a decrease in anxiety-related behaviors suggesting an anxiolytic-like effect of this polyphenol. The anti-anxiety effect was blocked by flumazenil suggesting that anxiety is reduced by activation of the benzodiazepine receptor. In vitro, chlorogenic acid protected granulocytes from oxidative stress. CONCLUSIONS Chlorogenic acid is one of the most abundant polyphenols in fruits. We demonstrated in vivo and in vitro for the first time, that chlorogenic acid has anxiolytic effects coupled with antioxidant activity. Thus, fruits such as plums (Mirabelle), apples and cherries may provide health-promoting advantages to consumers.

Phytochemical Composition and Antioxidant Capacity of Three Malian Medicinal Plant Parts

This study evaluates the levels of total polyphenolic compounds in three Malian medicinal plants and determines their antioxidant potential. Quantitative and qualitative analysis of polyphenolics contained in plants extracts were carried out by RP-C18 RP–HPLC using UV detector. The antioxidant activity was determined by three tests. They are phosphomolybdenum, DPPH (2,2-diphenyl-1 picrylhydrazyl) and ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic)] tests. The total phenolic and the total flavonoid contents varied from 200 to 7600 mg 100 g−1 dry weight (dw), expressed as gallic acid equivalents and from 680 to 12 300 mg 100 g−1 dw expressed as catechin equivalents, respectively. The total anthocyanin concentrations expressed as cyanin-3-glycoside equivalent varied from 1670 to 28 388 mg 100 g−1 dw. The antioxidant capacity was measured by determining concentration of a polyphenolic (in mg ml−1) required to quench the free radicals by 50% (IC50) and expressed as vitamin C equivalent antioxidant capacity. The IC50 values were ranked between 2.68 and 8.80 μg ml−1 of a solution of 50% (v/v) methanol in water. The uses of plants are rationalized on the basis of their antioxidant capacity.

The Therapeutic Benefits of Essential Oils

Since ancient times, essential oils are recognized for their medicinal value and they are very interesting and powerful natural plant products. They continue to be of paramount importance until the present day. Essential oils have been used as perfumes, flavors for foods and beverages, or to heal both body and mind for thousands of years (Baris et al., 2006; Margaris et al., 1982; Tisserand, 1997; Wei & Shibamoto 2010). Record findings in Mesopotamia, China, India, Persia and ancient Egypt show their uses for many treatments in various forms. For example, in the ancient Egypt, the population extracted oils by infusion. Later; Greeks and Romans used distillation and thus gave aromatic plants an additional value. With the advent of Islamic civilization, extraction techniques have been further refined. In the era of the Renaissance, Europeans have taken over the task and with the development of science the composition and the nature of essential oils have been well established and studied (Burt, 2004; Peeyush et al., 2011; Steven, 2010; Suaib et al., 2007). Nowadays, peppermint, lavender, geranium, eucalyptus, rose, bergamot, sandalwood and chamomile essential oils are the most frequently traded ones.

Assessment of polyphenolic compounds, in vitro antioxidant and anti-inflammation properties of Securidaca longepedunculata root barks

The present study was carried out to evaluate the antioxidant activities of the root bark extract of Securidaca longepedunculata. This plant material is commonly used in folk medicine in several parts in the world. The bark extracts of S. longepedunculata were evaluated for their total phenols, flavonoids, anthocyanins, tannins content and total antioxidant capacity. The compounds were identified and quantified both by RP-HPLC and UV spectrophotometer; the antioxidant capacity was assessed by ABTS and DPPH tests and expressed as IC(50). The total phenolic compounds determinate was 9.86mg gallic acid equivalents/g dw, the total flavonoid contents was 5.85mg catechin equivalents/g dw, the total anthocyanin contents was 0.032mg cyanidin-3-glycosyl equivalents/g dw and the condensed tannins content were 1.03mg catechin equivalents/g dw. The major compound identified using RP-HPLC was quercetin (0.98mg/ml). The IC(50) value reached 5.5microg/ml, revealing that the root barks of S. longepedunculata have a very high antioxidant and anti-inflammation properties.

New extraction technique for alkaloids

A method of extraction of natural products has been developed. Compared with existing methods, the new technique is rapid, more efficient and consumes less solvent. Extraction of alkaloids from natural products such as Hyoscyamus muticus, Datura stramonium and Ruta graveolens consists of the use of a sonicated solution containing a surfactant as extracting agent. The alkaloids are precipitated by Mayer reagent, dissolved in an alkaline solution, and then extracted with chloroform. This article compares the results obtained with other methods showing clearly the advantages of the new method.

Chemical Composition and, Cellular Evaluation of the Antioxidant Activity of Desmodium adscendens Leaves

Desmodium adscendens plant is widely used as juice or tea in various parts of the world against a wide range of diseases. This study determines the quality and the quantity of polyphenols, flavonoids, anthocyanins, and tannins in D. adscendens leaves by UV-spectrophotometry and RP-HPLC methods. In addition, the antioxidant capacity of these phenolic compounds is evaluated by ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic)), DPPH (2,2-diphenyl-1 picrylhydrazyl), and Cellular tests. D. adscendens leaves are mainly composite of flavonoid compounds with 12.8 mg of catechin equivalent (CE)/g dw. The amounts of total polyphenol compounds are 11.1 mg of gallic acid equivalent (GAE)/g dw. The quantity of total anthocyanin and total tannin compounds is not considerable 0.0182 mg CgE/g dw and 0.39 mg CE/g dw, respectively. A direct correlation between phenolic compounds and antioxidant activity is observed (R 2 = 0.96). The RP-HPLC analyses reveal that the main phenolic compound identified in the methanol-water extract is quercetrin dihydrat (2.11 mg/mL). According to the results, it is observed that D. adscendens leaves possess a considerable scavenging antioxidant and antiradical capacity, therefore these antioxidant properties might increase the therapeutic value of this medicinal plant.

Medium effects in unsymmetrical disulfides compounds synthesis from bunte salts

Abstract The present study allows us to show the influence of the polarity of the reaction medium as well as the electron-donating and withdrawing character of para substituents of α-halogeno toluenes in the preparation of unsymmetrical disulfides using the Bunte salt method. The use of DMSO as a reaction solvent permits not only to dissociate the sodium salt, but also to synthesise unsymmetrical disulfides from compounds which are inadequate using conventional methods.

Chemical Composition and Antioxidant Potential of Ruta montana L. Essential Oil from Algeria

The essential oil of aerial parts of Ruta montana L. growing in the Oran region in the west of Algeria was obtained by hydrodistillation with a 1.63% yield on a dry weight basis. Gas chromatography (GC) and GC/mass spectrometry (MS) analyses were carried out to identify the chemical composition of R. montana essential oil. Moreover, spectrophotometric analyses were employed to highlight the scavenger capacity of this oil using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test. Twenty compounds were identified by GC and CG/MS analyses, and the bulk of the compounds of the oil were undecan-2-one (32.8%), nonan-2-one (29.5%), nonanol-2-acetate (18.2%), and psoralen (3.5%). The results obtained using the DPPH test show that R. montana essential oil possesses antiradical activity in a concentration-dependent manner. Thus, a linear correlation (correlation coefficient R(2) = 0.971, P < .001) was found between the reduction of DPPH stable free radical and the concentration of R. montana essential oil.

Étude ethnobotanique et historique des tamaris (Tamarix sp., tamaricaceae) et leurs usages actuels en Afghanistan

Resumé:Cette étude ethnobotanique portant sur les tamaris comporte une présentation des espèces répertoriées en Afghanistan, une tentative de précision de la place qu’ont occupée ces arbres ou arbustes au cours de l’Histoire et une comparaison entre les usages thérapeutiques de diverses parties des tamaris dans la pratique actuelle de la médecine traditionnelle afghane, en relation avec leur composition chimique, et enfin les données mentionnées dans les ouvrages anciens arabo-persans.Abstract:In this ethno-botanical survey, in the first time different species of tamarisk indexed in Afghanistan are presented. and the importance of this tree or bush in times past is made clear. In a second time the historical aspect of these trees is make clear during some old civilizations. Finally, Comparisons are made between the actual present uses of the different parts of the tamarisk species in the traditional Afghan medicine therapy of Afghanistan in relation to their chemical composition, and finally the data are compared with the data mentioned in the old arabo-persian texts.

Caractérisation et bioévaluation des polyphénols: nouveaux domaines d’application en santé et nutrition

RésuméDans cette étude, nous avons montré que plusieurs variétés de prunes permettent la protection des granulocytes contre le stress oxydant par leur potentiel inhibiteur d’accumulation intracellulaire des espèces réactives de l’oxygène (ERO) qui sont très cytotoxiques et impliquées dans de nombreux troubles. Ainsi, la consommation de 100 g de prunes fraîches correspondrait en effet antioxydant à l’équivalent de 614 et 2 138 mg de vitamine C. Le profil chimique des polyphénols majoritaires des prunes a été établi par nos études grâce à des méthodes analytiques de chromatographie (CLHP) montrant que l’acide néochlorogénique est le polyphénol prédominant. Les prunes se sont également révélées une source de polyphénols ayant un double effet: antioxydant et anxiolytique, tels que l’acide chlorogénique, ce qui donne aux polyphénols de nouveaux champs d’applications dans le domaine de la prévention.AbstractIn the present study, we have shown that plums protected granulocyte cells from oxidative stress by their potential to inhibit the intracellular reactive oxygen species accumulation. The consumption of 100 g of fresh plums can provide antioxidants equivalent to 613.98–2137.59 mg of vitamin C. The major polyphenols in plums were identified and quantified using reversed-phase high-performance liquid chromatography (HPLC), which revealed that neochlorogenic acid was the predominant polyphenol. Plums are a source of polyphenols with dual effects: antioxidant and anxiolytic, like chlorogenic acid, which may provide health-promoting advantages to the consumer.