Acute toxicity and antioxydant property of Striga hermonthica (Del.) Benth (Scrophulariaceae)

Plants containing flavonoids have been reported to possess strong antioxidant properties. The aqueous acetone extract of Striga hermonthica was further separated into aqueous and ethyl acetate fractions and assayed for their in vitro antioxidant properties using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Thecrude extract exhibits a weak antioxidant activity (IC50 of 95.27±2.30 ìg/ml) and an insignificant acute toxicity on mice (LD50: 1753±44 mg/kg). Luteolin was isolated and identified by mean of its spectral data as the main DPPH radical scavenger of the ethyl acetate fraction, exhibiting an IC50 value of 6.80±1.46 ìg/ml. These results suggest an antioxidant potential for S. hermonthica

Anti-proliferative effect of Scoparia dulcis L. against bacterial and fungal strains

Scoparia dulcis L. was sequentially extracted with hexane, chloroform and methanol and soaked with aqueous-acetone (80%) to check for its antimicrobial activities against five bacterial and four fungal strains.250μg of each extract loaded on a whatman paper disc exhibited significant antimicrobial activities on all the fungus and against Gram-negative and Gram-positive bacteria. Therefore, P. mirabilis is less sensitive to all the extracts while B. cereus, a â-lactamase producer bacterium, was resistant to the activity of the polar methanol and aqueous-acetone extracts. By the microdilution method, the most active extracts were chloroform extract on B. cereus with minimal inhibitory concentration (MIC) of 1.56 mg/ml and Aqueous-acetone extract on S. typhimurium (MIC = 1.56 mg/ml); the antifungal activity was strongest for hexane extract (MIC = 6.25 mg/ml) on both A. niger and P. roquefortii.Keywords: Scoparia dulcis, Antibacterial, Antifungal, Polyphenols

The phytochemical composition and <i>in vitro</i> antiviral activity of decoctions from galls of <i>Guiera senegalensis</i> J.F. Gmel. (<i>Combretaceae</i>) and their relative non-toxicity for chickens

Aqueous decoctions obtained from the galls of Guiera senegalensis were screened to determine their phytochemical composition and in vitro antiviral activity against fowlpox virus. In addition, we wanted to investigate the toxic effects, if any, of crude extracts in chickens. Steroids as well as cardiac glycosides not previously reported, an alkaloid, polyphenols and saponins were detected in the various fractions of organic solvents used for extracting the decoctions. Antiviral activity was determined by cytopathic effect inhibition assay in primary chicken embryo skin cells. The 50 % inhibitory concentration (EC50) was shown to be 15.6 µg/ml. Toxicity for cells was established by determining the 50 % cytotoxic concentration (CCy50). A value of 90 µg/ml and a selectivity index (CCy50/EC50) of 5.8 were obtained. In vivo studies of toxicity were performed in chickens that were dosed orally with decoctions of several concentrations for 2 weeks and then monitored for 3 months. No significant changes in several blood chemical parameters were obtained, except for a significant decline in SGOT levels in birds dosed with 100 mg/kg. These levels were nevertheless within the accepted normal range. The findings suggest that aqueous decoctions of galls from G. senegalensis are non-toxic for chickens when administered orally, even at a daily dose of 100 mg/kg for 14 days

Experimental design optimization for screening relvant free phenolic acids from various preparations used in Burkina Faso folk medicine

International audienc

VARIABILITY OF ROSMARINIC ACID, CARNOSIC ACID AND ANTIOXIDANT ACTIVITY IN THE SAGE COLLECTION OF THE GENEBANK IN GATERSLEBEN

Salvia officinalis L. (common sage) is a well-known medicinal plant with a variable essential oil composition, and an interesting anti-oxidative potential which is due predominantly to two main substances and their derivatives, rosmarinic and carnosic acid. In this study the rosmarinic acid, caffeic acid and some anti-oxidative parameters (total flavonoids, total phenolics, DPPH, FRAP) of 19 accessions of sage were evaluated in the sage collection of the genebank in Gatersleben (Germany). The aerial parts of 10 individual plants of each accession cultivated in 2006, were collected two times (2007 and 2008, from the same experimental field) at the beginning of the flowering period, and used for this study. The rosmarinic acid content was 6-46 mg/g in 2007 and 9-25 mg/g in 2008, and correlated well with all the other antioxidant parameters e.g. total flavonoid, total phenolics, DPPH (2,2-diphenyl-1-picrylhydrazyl ) and FRAP (Ferric reduction antioxidant power)antioxidant activities. The carnosic acid evaluated only with 2008 sample was varying from 0.5 to 4.3 mg/g and had low significant correlation with the antioxidant parameters. The results showed altogether the high potential of S. officinalis which is already in use as a natural antioxidant, due to its main phenolic compound, rosmarinic acid and carnosic acid. The present study showed a high variability between and also within accessions through the studied parameters, which could be exploited by plant breeders in sage genotype selection

THE VARIABILITY OF THE ESSENTIAL OIL COMPOSITION IN THE SAGE COLLECTION OF THE GENEBANK GATERSLEBEN

Genebanks are valuable resources for ex-situ conservation and breeding of economic plants and wild plant relatives. Analysing plant secondary compounds of such collections delivers useful information about the variability (heterogeneity) in the collection and enables plant breeders to pre-select accessions when breeding for specific plant secondary compounds like essential oil content and/or composition. For garden sage (Salvia officinalis L.), 10 individual plants of each of the 19 accessions available in the genebank were analysed for their essential oil content and composition. The essential oil content was in the range of 0.8% to 2.4%. The essential oil composition was comparable to results already published with the exception of two accessions, which were very low in α-thujone (3%) and β-thujone

Antibacterial Potential of Aqueous Acetone Extracts from Five Medicinal Plants Used Traditionally to Treat Infectious Diseases in Burkina Faso

Abstract: Polyphenol contents, in vitro antioxidant and antimicrobial activities of leaves and barks from of Anogeissus leiocarpus, Khaya senegalensis, Sterculia setigera, Solanum incanum and Pterocarpus erinaceus extracts obtained with aqueous acetone 80% (WAE) were investigated in this study. The present study was conducted to evaluate the total phenolic contents, in vitro antioxidant and antibacterial properties. Folinciocalteu and AlCl 3 methods, respectively were used for polyphenol contents. The antioxidant potential of the samples was evaluate using two separate methods, inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Iron (III) to iron (II) reduction activity (FRAP). In vitro antibacterial capacity of aqueous acetone extracts were investigated by agar disc diffusion, micro-well dilution (MIC) and Minimum Bactericidal Concentration (MBC) assay against five bacteria. Our extracts contained high levels of phenolics and exhibited antibacterial activity against bacteria. S. aureus and B. cereus were the most sensitive; while E. coli was the most resistant. There were highly positive relationships (R 2 = 0.8454-0.9780) between phenolic contents and antioxidant, activity antibacterial capacity and phenolic contents of the tested extracts against each bacterium. This suggested that the antibacterial activity of the tested extracts was closely associated with their phenolic constituents. In this study, the extract of Anogeissus leiocarpus leaves was presented the best results among all extracts