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1.
An. acad. bras. ciênc ; 89(3): 1671-1681, July-Sept. 2017. tab, graf
Article Dans Anglais | LILACS | ID: biblio-886765

Résumé

ABSTRACT Fatty acid methyl esters (FAMEs) were obtained from vegetable oils of soybean, corn and sunflower. The current study was focused on evaluating the antifungal activity of FAMEs mainly against Paracoccidioides spp., as well as testing the interaction of these compounds with commercial antifungal drugs and also their antioxidant potential. FAMEs presented small IC50 values (1.86-9.42 μg/mL). All three FAMEs tested showed antifungal activity against isolates of Paracoccidioides spp. with MIC values ranging from 15.6-500 µg/mL. Sunflower FAMEs exhibited antifungal activity that extended also to other genera, with an MIC of 15.6 μg/mL against Candida glabrata and C. krusei and 31.2 μg/mL against C. parapsilosis. FAMEs exhibited a synergetic effect with itraconazole. The antifungal activity of the FAMEs against isolates of Paracoccidioides spp. is likely due to the presence of methyl linoleate, the major compound present in all three FAMEs. The results obtained indicate the potential of FAMEs as sources for antifungal and antioxidant activity.


Sujets)
Paracoccidioides/effets des médicaments et des substances chimiques , Picrates/pharmacologie , Glycine max/composition chimique , Dérivés du biphényle/pharmacologie , Huiles végétales/pharmacologie , Zea mays/composition chimique , Helianthus/composition chimique , Antifongiques/pharmacologie , Picrates/isolement et purification , Dérivés du biphényle/isolement et purification , Huiles végétales/composition chimique , Tests de sensibilité microbienne , Résistance des champignons aux médicaments , Dose létale 50 , Chromatographie gazeuse-spectrométrie de masse , Antifongiques/isolement et purification
2.
Biol. Res ; 47: 1-6, 2014. tab
Article Dans Anglais | LILACS | ID: lil-710933

Résumé

BACKGROUND: Several plants are reported to be produced various biological active compounds. Lichens from the extreme environments such as high altitude, high UV, drought and cold are believed to be synthesized unique types of secondary metabolites than the other one. Several human pathogenic bacteria and fungi have been muted into drug resistant strains. Various synthetic antioxidant compounds have posed carcinogenic effects. This phenomenon needs further research for new effective drugs of natural origin. This manuscript aimed to screen new source of biological active compounds from plants of subarctic origin. RESULTS: A total of 114 plant species, including 80 species of higher plants, 19 species of lichens and 15 species of mosses, were collected from Oymyakon region of the Republic of Sakha (Yakutia), Russia (63˚20′N, 141˚42′E - 63˚15′N, 142˚27′E). Antimicrobial, DPPH free radical scavenging and brine shrimp (Artemia salina) toxicity of all crude extract were evaluated. The obtained result was analyzed and compared with commercial standards. A total of 28 species of higher plants showed very strong antioxidant activity (DPPH IC50, 0.45-5.0 µg/mL), 13 species showed strong activity (DPPH IC50, 5-10 µg/mL), 22 species showed moderate antioxidant activity (DPPH IC50,10-20 µg/mL) and 17 species showed weak antioxidant activity (DPPH IC50 more than 20 µg/mL). Similarly, 3 species of lichen showed strong antioxidant activity, one species showed moderate and 15 species showed weak DPPH reducing activity. In addition, 4 species of mosses showed moderate antioxidant activity and 11 species showed weak antioxidant activity. Similarly, extracts of 51 species of higher plants showed antimicrobial (AM) activity against Staphylococcus aureus and 2 species showed AM activity against Candida albicans. Similarly, 11 species of lichen showed AM activity against S. aureus and 3 species showed AM activity against Escherichia coli. One species of moss showed AM activity against S. aureus. And finally, one species of higher plant Rheum compactum and one species of lichen Flavocetraria cucullata showed the toxicity against Brine shrimp larvae in 100 µg/mL of concentration. CONCLUSION: The experimental results showed that subarctic plant species could be potential sources of various biologically active natural compounds.


Sujets)
Animaux , Anti-infectieux/pharmacologie , Antioxydants/pharmacologie , Artemia/effets des médicaments et des substances chimiques , Deuteromycota/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Anti-infectieux/analyse , Antioxydants/analyse , Aspergillus niger/effets des médicaments et des substances chimiques , Produits biologiques/pharmacologie , Dérivés du biphényle/pharmacologie , Candida albicans/effets des médicaments et des substances chimiques , Escherichia coli/effets des médicaments et des substances chimiques , Lichens/métabolisme , Picrates/pharmacologie , Russie , Rheum/composition chimique , Rhododendron/composition chimique , Rosaceae/composition chimique , Staphylococcus aureus/effets des médicaments et des substances chimiques , Tests de toxicité
3.
Indian J Exp Biol ; 2013 Jan; 51(1): 81-87
Article Dans Anglais | IMSEAR | ID: sea-147571

Résumé

Leaf extracts of C. vamana, endemic to Kerala state in India, were found to inhibit cell cycle progression in synchronous cultures of P. polycephalum in a concentration and phase-specific manner. Crude alkaloid extract (CAE) elicited maximum cell cycle delays in comparison to soxhletted chloroform, acetone and aqueous extracts. Total alkaloid content of CAE was found to be 64.9 mg/g. CAE showed lowest DPPH radical scavenging activity. Other extracts with higher free radical scavenging activity exhibited lesser cell cycle inhibiting potential. Upto 21% decrease in nuclear DNA was observed in CAE treated samples. However, genotoxicity as evidenced by comet assay was not observed. The extracts were also found to be non-toxic to human RBCs at the highest concentration tested (750 µg/mL). CAE treatment completely suppressed a 63 kDa polypeptide with a concomitant, but weak induction of a 60 kDa polypeptide suggesting that these may be cell cycle related. CAE was found to possess potent antiproliferative activity against PBLs. The study clearly demonstrates the cell cycle inhibitory activity of C. vamana leaf extracts, with CAE being the most potent of them.


Sujets)
Alcaloïdes/pharmacologie , Dérivés du biphényle/pharmacologie , Cycle cellulaire , Noyau de la cellule/métabolisme , Prolifération cellulaire , Test des comètes/méthodes , Curcuma/métabolisme , Altération de l'ADN , Relation dose-effet des médicaments , Cytométrie en flux/méthodes , Radicaux libres/composition chimique , Humains , Lymphocytes/cytologie , Mitose , Modèles biologiques , Physarum polycephalum/métabolisme , Picrates/pharmacologie , Extraits de plantes/pharmacologie , Feuilles de plante/métabolisme
4.
Biol. Res ; 39(2): 281-288, 2006. ilus, tab
Article Dans Anglais | LILACS | ID: lil-432430

Résumé

Free radicals induce numerous diseases by lipid peroxidation, protein peroxidation, and DNA damage. It has been reported that numerous plant extracts have antioxidant activities to scavenge free radicals. Whether Polygonum aviculare L. (Polygonaceae) has antioxidant activity is unknown. In this study, dried Polygonum aviculare L. was extracted by ethanol, and the extract was lyophilized. The antioxidant activities of extract powder were examined by free radical scavenging assays, superoxide radical scavenging assays, lipid peroxidation assays and hydroxyl radical-induced DNA strand scission assays. The results show that the IC50 value of Polygonum aviculare L. extract is 50 µg/ml in free radical scavenging assays, 0.8 µg/ml in superoxide radical scavenging assays, and 15 µg/ml in lipid peroxidation assays, respectively. Furthermore, Polygonum aviculare L. extract has DNA protective effect in hydroxyl radical-induced DNA strand scission assays. The total phenolics and flavonoid content of extract is 677.4 ± 62.7 µg/g and 112.7 ± 13 µg/g. The results indicate that Polygonum aviculare L. extract clearly has antioxidant effects.


Sujets)
Animaux , Mâle , Souris , Antioxydants/pharmacologie , Altération de l'ADN/effets des médicaments et des substances chimiques , Piégeurs de radicaux libres/pharmacologie , Peroxydation lipidique/effets des médicaments et des substances chimiques , Polygonum/composition chimique , Flavonoïdes/analyse , Hydroxybenzoates , Souris de lignée BALB C , Bleu de nitrotétrazolium/pharmacologie , Picrates/pharmacologie , Extraits de plantes/pharmacologie , Thiobarbituriques/pharmacologie
5.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 198-200, 2003.
Article Dans Anglais | WPRIM | ID: wpr-635324

Résumé

To investigate the effects of the free radical, 1,1-Diphenyl-2-picylhydrazyl, on cochlear blood flow, 20 guinea pigs were divided into 3 groups at random, 6 for control group, 6 for 1 mmol/L group and 8 for 0.1 mmol/L group. 2 microliters vehicle or drugs were dropped into round window membrane (RWM). Cochlear microcirculation was monitored by laser Doppler flowmeter (LDF), and mean arterial blood flow (MABP), which was transferred by pressure conductor sensor and preamplifier, was simultaneously recorded on the computer. Our results showed that MABP was stable throughout the experiment. Cochlear blood flow (CBF) increased by 10.32% (P < 0.05) in 1 mmol/L group, and decreased by 4.89% in 0.1 mmol/L group (P < 0.05). In control group cochlear microcirculation showed no significant changes. It is concluded that DPPH exerted effects on cochlear microcirculation.


Sujets)
Vitesse du flux sanguin , Cochlée/vascularisation , Radicaux libres/pharmacologie , Fluxmétrie laser Doppler , Microcirculation/effets des médicaments et des substances chimiques , Picrates/pharmacologie , Répartition aléatoire
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