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1.
Arch Microbiol ; 205(4): 110, 2023 Mar 08.
Article de Anglais | MEDLINE | ID: mdl-36884139

RÉSUMÉ

This study aims to identify and assess the antimicrobial activity of endophytic fungi found in the endemic plant Abies numidica. Among all isolates, the ANT13 isolate demonstrated significant antimicrobial activity in the preliminary screening, particularly Staphylococcus aureus ATCC 25923 and Candida albicans ATCC 1024, with inhibition zones of 22 and 21.5 mm, respectively. Based on its morphological and molecular features, this isolate was identified as Penicillium brevicompactum. The maximum activity was observed in the ethyl acetate extract, followed by the dichloromethane extract; however, the n-hexane extract exhibited no activity. The ethyl acetate extract demonstrated very significant activity against the five strains of multidrug-resistant Staphylococcus aureus used, with average zones of inhibition ranging from 21 to 26 mm, in contrast to more resistant Enterococcus faecalis ATCC 49452 and Bacillus cereus ATCC 10876. The ethyl acetate extract was also very active against dermatophytes, where the zones of inhibition for Candida albicans, Microsporum canis, Trichophyton mentagrophytes, Trichophyton rubrum, and Epidermophyton floccosum were 23.5, 31, 43, 47, and 53.5 mm, respectively. The MIC values for dermatophytes ranged between 100 and 3200 µg/mL. The wild isolate of Penicillium brevicompactum ANT13 discovered as an endophyte in Abies numidica may be a distinctive source of novel compounds and drug discovery to trait dermatophytes and multidrug-resistant Staphylococcus aureus infections.


Sujet(s)
Abies , Anti-infectieux , Staphylococcus aureus résistant à la méticilline , Infections à staphylocoques , Staphylococcus aureus , Tests de sensibilité microbienne , Anti-infectieux/pharmacologie , Antifongiques/pharmacologie
2.
J Ethnopharmacol ; 301: 115771, 2023 Jan 30.
Article de Anglais | MEDLINE | ID: mdl-36206871

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Species of Echium trygorrhizum Pomel, belonging to the Boraginaceae family, grow wild in North Africa. This plant is used in traditional Algerian medicine for the treatment of Diabetes, Jaundice and Tonsillitis. AIM OF THE STUDY: To our knowledge, no work has been done on the phytochemistry and biological activities of this plant. Moreover, no study has yet corroborated that the use of this plant is safe. Therefore, the present study was carried out to gather information on the various medicinal uses of this plant and to evaluate the total phenolic content and assess its safety after acute and sub-acute toxicity tests with rodents (mice and rats). MATERIAL AND METHODS: An ethnopharmacological survey was carried out using a direct questionnaire. It included some questions relating to the plant. The content of polyphénols, flavonoids and tannins present in the aqueous extract was determined by colorimetric methods. In the acute toxicity tests, three groups each containing five males and five females Albino mice were formed. The control group received water, while the test groups received different doses of aqueous extract (2000 and 5000) mg/kg body weight. In the subacute toxicity study, different doses (250, 500 and 1000 mg/kg) of the aqueous extract were administered to male and female rats for 28 consecutive days. Hematological analysis, biochemical parameters estimation and histopathological examination have been determined at the end of the treatment. RESULTS: Data from the ethnopharmacological survey showed that 25, 31% of people used this plant in Algeria as a traditional medicine for the treatment of Jaundice (100%), Diabetes (28, 33%) and Tonsillitis (10%). Results also revealed that aqueous extract contains high amounts of polyphenols, flavonoids and tannins. The extract did not cause any toxicity during the 14-days observation period after a single dose of 5000 mg/kg was administered to mice, with LD50 values greater than 5000 mg/kg. In a further step, the administration of the aqueous extract at all dose levels (250, 500, and 1000 mg/kg) to male and female rats during the 28-days study did not result in any deaths or behavioral changes, and there were no changes in body weight, relative organ weights, or food consumption as a result of this experiment. However, male rats showed a significant difference in relative liver weight in the high dose group (1000 mg/kg) (p < 0.05) and the satellite group (p < 0.01). In female rats, liver weight significantly increased only in the satellite group compared with the control group (p < 0.01). The results showed an increase in red blood cells (RBC), hemoglobin (Hb), and hematocrit (Hct) in the female groups. However, a clear decrease was observed in plasma ALP enzyme activities in females treated with the doses of 250 and 1000 mg/kg (p < 0.05) after the treatment periods. CONCLUSION: The study indicated that the single dose of 5 g/kg AQE can be considered relatively safe as it did not cause death or any signs of toxicity in mice. Repeated oral administration of AQE at doses below 250 g/kg/day for 28 consecutive days can be considered relatively safe.


Sujet(s)
Echium , Amygdalite , Mâle , Femelle , Rats , Animaux , Souris , Algérie , Extraits de plantes/composition chimique , Rat Wistar , Tests de toxicité aigüe , Eau , Tanins , Flavonoïdes , Poids
3.
Comb Chem High Throughput Screen ; 25(6): 1058-1071, 2022.
Article de Anglais | MEDLINE | ID: mdl-33655855

RÉSUMÉ

BACKGROUND: Due to the strong association between the chemistry of medicinal plants and their biological properties, it is important to determine their phytochemical composition to justify experimental tests. OBJECTIVE: The aim of this study was to evaluate the in vitro antioxidant and the enzyme inhibitory properties and to identify the bioactive compounds present in the extracts of Ephedra nebrodensis growing in Algeria. METHODS: Total phenolic and flavonoids content in these extracts were quantified by Folin- Ciocalteu and aluminum chloride methods. The antioxidant capacity was assessed using DPPH, ABTS, ß-carotene/linoleic acid, CUPRAC and FRAP assays, and in vitro cholinesterase activity against acetylcholinesterase and butyrylcholinesterase were evaluated. The chemical constituents of the extracts were analyzed by high-performance liquid chromatography coupled with mass spectrometric detection and gas chromatography. For the acute toxicity study, extracts were administered to mice at single dose of 2 g/kg and 5 g/kg by gavage. RESULTS: Plant extracts were rich in phenolic compounds. Ethyl acetate extract presented the highest phenolic (238.44 ± 1.50 µg GAE /mg of extract) and flavonoid (21.12 ± 0.00 µg QE /mg of extract) contents. Likewise, ethyl acetate extract showed potent radical scavenging and reducing properties. Ethanol-acetone extract showed inhibitory activity against acetylcholinesterase, and was a potent inhibitor of butyrylcholinesterase. In all extracts, flavonoids were the most abundant compounds. The phytochemical investigation showed the presence of alkaloids (ephedrine and pseudo-ephedrine). In the acute toxicity, the LD50 was superior to 5 g/kg body weight. There were no alterations in the histology of the liver and kidneys. CONCLUSION: This study demonstrated a good antioxidant potential and anticholinesterase activity of aerial parts of E. nebrodensis.


Sujet(s)
Antioxydants , Ephedra , Acetylcholinesterase , Animaux , Antioxydants/composition chimique , Butyrylcholine esterase/analyse , Éphédrine/analyse , Flavonoïdes/composition chimique , Flavonoïdes/pharmacologie , Souris , Phénols/composition chimique , Composés phytochimiques/composition chimique , Composés phytochimiques/pharmacologie , Parties aériennes de plante/composition chimique , Extraits de plantes/composition chimique , Extraits de plantes/pharmacologie
4.
J Ethnopharmacol ; 271: 113881, 2021 May 10.
Article de Anglais | MEDLINE | ID: mdl-33508369

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Erica arborea known as Khlenj in Algeria is a small shrub belonging to Ericaceae family. E. arborea Aqueous extract (EAAE) is used in traditional medicine for anti-inflammatory, diuretic, antimicrobial, and antiulcer purposes. AIM OF THE STUDY: To our knowledge, no data reveal the combination between in-vivo anti-inflammatory and toxicological studies of EAAE. For this purpose, the aim of this study is to evaluate the biological activity cited above and assess its safety. MATERIAL AND METHODS: Anti-inflammatory activity was undergone using carrageenan-induced paw edema and croton oil-induced ear edema. The acute and sub-acute toxicity were conducted following the OECD guidelines 423 and 407, respectively. Phytochemical identification was carried out using HPLC-DAD-MS. Quantitative evaluation of polyphenols; flavonoids and antioxidant activity of EAAE were also determined. RESULTS: Oral administration of EAAE (250 and 500 mg/kg) significantly (p < 0.05) reduced the edema induced by carrageenan. Administration of EAAE dosed at 250 and 500 mg/kg exhibited efficacy in reducing edema induced by croton oil. The acute administration of EAAE at doses of 2000 and 5000 mg/kg did not cause any mortality or adverse effects indicating that the LD50 is above 5000 mg/kg. The prolonged administration of EAAE (500 and 1000 mg/kg) showed a significant reduction in triglycerides levels in male and female rats whereas no significant changes in other biochemical and hematological parameters were observed. Histopathological damages were recorded in both liver and kidney animal's tissues of both sexes treated with medium and maximum doses of EAAE. Phytochemical characterization of EAAE revealed a high amount of phenolic compounds, HPLC-DAD-MS analysis led to the identification of chlorogenic acid and five flavonol glycosides: myricetin pentoside, quercetin-3-O-glucoside, myricetin-3-O-rhamnoside, quercetin-3-O-pentoside, and quercetin-3-O-rhamnoside. CONCLUSION: In the light of the results obtained in this study, EAAE corroborates the popular use to treat the anti-inflammatory impairments. EAAE can be considered as non-toxic in acute administration and exhibited a moderate toxicity in sub-acute administration. High phenolic content and in-vitro antioxidant activity observed indicate that EAAE may reduce oxidative stress markers in-vivo.


Sujet(s)
Anti-inflammatoires/administration et posologie , Anti-inflammatoires/effets indésirables , Oedème/traitement médicamenteux , Ericaceae/composition chimique , Parties aériennes de plante/composition chimique , Extraits de plantes/administration et posologie , Extraits de plantes/effets indésirables , Administration par voie orale , Algérie , Animaux , Anti-inflammatoires/toxicité , Antioxydants/pharmacologie , Poids/effets des médicaments et des substances chimiques , Carragénane/toxicité , Huile de croton/toxicité , Oedème/induit chimiquement , Femelle , Rein/effets des médicaments et des substances chimiques , Foie/effets des médicaments et des substances chimiques , Mâle , Médecine traditionnelle , Composés phytochimiques/administration et posologie , Composés phytochimiques/effets indésirables , Composés phytochimiques/analyse , Composés phytochimiques/toxicité , Extraits de plantes/toxicité , Rat Wistar , Appréciation des risques , Triglycéride/métabolisme , Eau/composition chimique
5.
Molecules ; 22(10)2017 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-28991218

RÉSUMÉ

Extracts from an endophytic fungus isolated from the roots of the Algerian plant Globularia alypum showed prominent antimicrobial activity in a screening for novel antibiotics. The producer organism was identified as Dendrothyrium variisporum by means of morphological studies and molecular phylogenetic methods. Studies on the secondary metabolite production of this strain in various culture media revealed that the major components from shake flasks were massarilactones D (1) and H (2) as well as two new furanone derivatives for which we propose the trivial names (5S)-cis-gregatin B (3) and graminin D (4). Scale-up of the fermentation in a 10 L bioreactor yielded massarilactone D and several further metabolites. Among those were three new anthranilic acid derivatives (5-7), two known anthranilic acid analogues (8 and 9) and three cyclopeptides (10-12). Their structures were elucidated on the basis of extensive spectroscopic analysis (1D- and 2D-NMR), high-resolution mass spectrometry (HRESIMS), and the application of the modified Mosher's method. The isolated metabolites were tested for antimicrobial and cytotoxic activities against various bacteria, fungi, and two mammalian cell lines. The new Metabolite 5 and Compound 9 exhibited antimicrobial activity while Compound 9 showed cytotoxicity activity against KB3.1 cells.


Sujet(s)
Anti-infectieux/composition chimique , Ascomycota/métabolisme , Furanes/composition chimique , ortho-Aminobenzoates/composition chimique , Animaux , Antibactériens/composition chimique , Antibactériens/isolement et purification , Antibactériens/pharmacologie , Anti-infectieux/isolement et purification , Antifongiques/composition chimique , Antifongiques/isolement et purification , Antifongiques/pharmacologie , Antinéoplasiques/composition chimique , Antinéoplasiques/isolement et purification , Antinéoplasiques/pharmacologie , Bioréacteurs , Extrait cellulaire/composition chimique , Lignée cellulaire , Survie cellulaire , Fermentation , Furanes/isolement et purification , Furanes/pharmacologie , Humains , Phylogenèse , Métabolisme secondaire , Relation structure-activité , ortho-Aminobenzoates/isolement et purification , ortho-Aminobenzoates/pharmacologie
6.
J Nat Prod ; 80(5): 1531-1540, 2017 05 26.
Article de Anglais | MEDLINE | ID: mdl-28398049

RÉSUMÉ

Six novel bioactive bicyclic polyketides (1-6) were isolated from cultures of an endophytic fungus of the medicinal plant Globularia alypum collected in Batna, Algeria. The producer organism was identified as Preussia similis using morphological and molecular phylogenetic methods. The structures of metabolites 1-6, for which the trivial names preussilides A-F are proposed, were elucidated using a combination of spectral methods, including extensive 2D NMR spectroscopy, high-resolution mass spectrometry, and CD spectroscopy. Preussilides were tested for antimicrobial and antiproliferative effects, and, in particular, compounds 1 and 3 showed selective activities against eukaryotes. Subsequent studies on the influence of 1 and 3 on the morphology of human osteosarcoma cells (U2OS) suggest that these two polyketides might target an enzyme involved in coordination of the cell division cycle. Hence, they might, for instance, affect timing or spindle assembly mechanisms, leading to defects in chromosome segregation and/or spindle geometry.


Sujet(s)
Anti-infectieux/isolement et purification , Anti-infectieux/pharmacologie , Penicillium/composition chimique , Polycétides/isolement et purification , Polycétides/pharmacologie , Anti-infectieux/composition chimique , Humains , Spectroscopie par résonance magnétique , Structure moléculaire , Phylogenèse , Polycétides/composition chimique
7.
Pharmacogn Mag ; 11(Suppl 1): S102-9, 2015 May.
Article de Anglais | MEDLINE | ID: mdl-26109754

RÉSUMÉ

BACKGROUND: Rhamnus alaternus (Rhamnaceae) L. has been traditionally used for treatment of many diseases. OBJECTIVE: In this study, we determined the antioxidant/free radical scavenger properties, the flavonoid profile and the cytotoxicity of aqueous and methanolic extracts obtained by maceration from Algerian R. alaternus bark, like also of aqueous extract prepared by decoction according to the traditional method. This to estimate the usefulness of the drug traditional preparation and compare it with those made in the laboratory. MATERIALS AND METHODS: The antioxidant activity of the extracts was evaluated using five different redox-based assays, all involving one redox reaction with the oxidant. High-performance liquid chromatography/diode array detection/electrospray ionization mass spectrometry analysis was used to identify and quantify the flavonoids content. Cytotoxicity on human monocytic leukemia cells (U937) was also carried out. RESULTS: All the extracts tested showed a good antioxidant/free radical scavenger activity and a similar flavonoid fingerprint. However, the methanolic one presented the best antioxidant activity that can be due to the highest flavonoid amount and significantly reduced the proliferation of leukemia cells. The results confirm that the extract prepared by decoction contains efficient antioxidant compounds and this justifies in part the therapeutic and preventive usefulness. Moreover, the methanolic extract exerted excellent cytotoxicity on U937 that could be attributed to kaempferol and rhamnocitrin glycosides.

8.
Biosci Microbiota Food Health ; 33(1): 11-23, 2014.
Article de Anglais | MEDLINE | ID: mdl-24936378

RÉSUMÉ

In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133.

9.
Biosci Biotechnol Biochem ; 77(1): 151-60, 2013.
Article de Anglais | MEDLINE | ID: mdl-23291759

RÉSUMÉ

A bacteriocin-producing (11,000 AU mL(-1)) strain was isolated from the rhizosphere of healthy Algerian plants Ononis angustissima Lam., and identified as Brevibacillus brevis strain GM100. The bacteriocin, called Bac-GM100, was purified to homogeneity from the culture supernatant, and, based on MALDI-TOF/MS analysis, was a monomer protein with a molecular mass of 4375.66 Da. The 21 N-terminal residues of Bac-GM100 displayed 65% homology with thurincin H from Bacillus thuringiensis. Bac-GM100 was extremely heat-stable (20 min at 120 °C), and was stable within a pH range of 3-10. It proved sensitive to various proteases, which demonstrated its protein nature. It was also found to display a bactericidal mode of action against gram-negative (Salmonella enteric ATCC 43972, Pseudomonas aeruginosa ATCC 49189, and Agrobacterium tumefaciens C58) and gram-positive (Enterococcus faecalis ENSAIA 631 and Staphylococcus aureus ATCC 6538) bacteria, and a fungistatic mode of action against the pathogenic fungus Candida tropicalis R2 CIP 203.


Sujet(s)
Anti-infectieux/isolement et purification , Anti-infectieux/métabolisme , Protéines bactériennes/isolement et purification , Protéines bactériennes/métabolisme , Bactériocines/isolement et purification , Bactériocines/métabolisme , Brevibacillus/composition chimique , Algérie , Anti-infectieux/pharmacologie , Bacillus thuringiensis/composition chimique , Protéines bactériennes/pharmacologie , Bactériocines/composition chimique , Bactériocines/pharmacologie , Brevibacillus/génétique , Brevibacillus/isolement et purification , Candida tropicalis/effets des médicaments et des substances chimiques , Candida tropicalis/croissance et développement , Enterococcus faecalis/effets des médicaments et des substances chimiques , Enterococcus faecalis/croissance et développement , Fabaceae/microbiologie , Température élevée , Concentration en ions d'hydrogène , Viabilité microbienne/effets des médicaments et des substances chimiques , Masse moléculaire , Phylogenèse , Stabilité protéique , Pseudomonas aeruginosa/effets des médicaments et des substances chimiques , Pseudomonas aeruginosa/croissance et développement , Rhizosphère , Salmonella enterica/effets des médicaments et des substances chimiques , Salmonella enterica/croissance et développement , Staphylococcus aureus/effets des médicaments et des substances chimiques , Staphylococcus aureus/croissance et développement
10.
Commun Agric Appl Biol Sci ; 77(3): 245-8, 2012.
Article de Anglais | MEDLINE | ID: mdl-23878980

RÉSUMÉ

The emergence of antibiotic-resistant micro-organisms calls for inventive research and development strategies. The screening for antimicrobial compounds from endophytes is a promising way to meet the increasing threat of drug-resistant strains of human and plant pathogens. Endophytes may be defined as "microbes that colonize living, internal tissues of plants without causing any immediate, overt negative effects". Endophytes are relatively unstudied as potential sources of novel natural products for exploitation in medicine, agriculture, and industry. The purpose of this study was to evaluate several isolated fungi from wheat (Triticum durum Desf.) Mohamed Ben Bachir variety and to select endophytic fungi for further evaluation of its antimicrobial, antioxidant activities and host growth promotion. A total of 20 endophytic fungi have been isolated. Antimicrobial activity was evaluated for crude ethyl acetate extracts using an agar diffusion assay. All extracts showed inhibitory activity on at least one or more pathogenic microorganism, with an average zone of inhibition varied between 7 mm to 25 mm, a large zone of 23 and 25mm against candida albicans and Escherichia coli respectively. The antioxidant capacity of the extracts was evaluated by beta-carotene/linoleic acid assay. Results showed that 70% of these extracts have antioxidant activity, exhibiting 50, 57% to 78, 96% inhibitions. While 30% from them, their inhibitory activity for oxidation of linoleic acid Were less than 50%. Growth promotion ability of these endophytes was tested on seed germination among ten isolates tested, two isolates showed significant growth promotion effects on wheat seeds. From the present work we can conclude that these microorganisms could be promising source of bioactive compounds, growth promotion and warrant further study.


Sujet(s)
Antioxydants/métabolisme , Endophytes/physiologie , Champignons/physiologie , Triticum/microbiologie , Bactéries , Lutte biologique contre les nuisibles , Feuilles de plante , Racines de plante
11.
Saudi Med J ; 30(11): 1422-5, 2009 Nov.
Article de Anglais | MEDLINE | ID: mdl-19882054

RÉSUMÉ

OBJECTIVE: To search whether xanthine oxido-reductase (XOR) present in the synovium is also liberated, to determine its activity in synovial fluid and to establish a possible relationship between XOR levels in rheumatoid arthritis (RA) and non-RA patients. METHODS: This study was carried out in the Laboratory of Immunology, University Ferhat Abbas, Setif, Algeria from 2001-2008. This study is a retrospective controlled study matching cases with RA to non rheumatoid joint inflammations. Synovial fluid (SF) samples were collected with consent of the patients, at Setif University Hospital, from adults suffering from RA (n=36) or only with joint inflammations (n=52). After its detection in SF with indirect enzyme-linked immunosorbent assay (ELISA) and dot-immunobinding, using anti-bovine XOR as first antibodies, XOR was assayed with capture ELISA. RESULTS: Xanthine oxidoreductase is found in all studied SF. Capture ELISA showed levels up to 0.762 and 0.143 mg/mL in SF of RA and other joint inflammations patients, respectively. In most cases, more than 50% of synovial XOR is present as oxidase form. Positive correlation was observed between enzyme level and the disease severity since RA patients had a significantly high enzyme amount compared to patients with other less severe arthritic pathologies. CONCLUSION: These results suggest that the enzyme could well be involved in joint inflammation probably by producing reactive oxygen species.


Sujet(s)
Polyarthrite rhumatoïde/sang , Synovie/enzymologie , Xanthine oxidase/métabolisme , Adulte , Arthrite/sang , Arthrite/diagnostic , Polyarthrite rhumatoïde/diagnostic , Marqueurs biologiques/sang , Études cas-témoins , Test ELISA , Femelle , Humains , Immunotransfert , Mâle , Adulte d'âge moyen , Arthrose/sang , Arthrose/diagnostic , Pronostic , Études rétrospectives , Indice de gravité de la maladie , Xanthine oxidase/analyse
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