Antioxidant and glucosidase activities and phytochemical constituents of Chrysanthoglossum trifurcatum (Desf.)

Objective: To investigate the antioxidant and glucosidase properties and phytochemical constituents of roots, stems, leaves and flowers extracts and aerial parts oil of Chrysanthoglossum trifurcatum (Desf.) (C. trifurcatum). Methods: For extraction from roots, stems, leaves and flowers of C. trifurcatum, methanol, ethyl acetate and petroleum ether solvents were used. Phenols, flavonoids, flavonols and tannins contents were evaluated. More, C. trifurcatum aerial parts oil composition was determined using chromatography/mass spectrometry. The antioxidant effect was estimated by DPPH, ABTS and reducing power test systems. The glucosidase inhibition was determined by colorimetric assay using the enzyme from Aspergillus Niger and the p-nitrophenyl glucopyranoside (pNPG) as substrate. Results: The highest amounts of polyphenols, flavonoids, flavonols and tannins were shown by the methanolic extract of leaves. The main components of the aerial parts oil were limonene (29.21%), γ -terpinene (12.96%), 4-terpenyl acetate (12.18%) and pinene (5.76%). The activity evaluated by DPPH, ABTS and reducing power tests was important for stems (IC

Antioxidant and α-glucosidase activities and phytochemical constituents of Chrysanthoglossum trifurcatum (Desf.)

Objective:To investigate the antioxidant and α-glucosidase properties and phytochemical constituents of roots, stems, leaves and flowers extracts and aerial parts oil of Chrysanthoglossum trifurcatum (Desf.) (C. trifurcatum).Methods:For extraction from roots, stems, leaves and flowers of C. trifurcatum, methanol, ethyl acetate and petroleum ether solvents were used. Phenols, flavonoids, flavonols and tannins contents were evaluated. More, C. trifurcatum aerial parts oil composition was determined using chromatography/mass spectrometry. The antioxidant effect was estimated by DPPH, ABTS and reducing power test systems. The α-glucosidase inhibition was determined by colorimetric assay using the enzyme from Aspergillus niger and the p-nitrophenyl glucopyranoside (pNPG) as substrate.Results:The highest amounts of polyphenols, flavonoids, flavonols and tannins were shown by the methanolic extract of leaves. The main components of the aerial parts oil were limonene (29.21%), γ -terpinene (12.96%), 4-terpenyl acetate (12.18%) and α -pinene (5.76%). The activity evaluated by DPPH, ABTS and reducing power tests was important for stems (ICConclusions:Observed antioxidant and α-glucosidase activities of oil and extracts are attributed to the presence of the active phytochemicals in C. trifurcatum organs. Thus, the C. trifurcatum can be used as a source of antioxidant compounds and dietary supplement to treat patients with type 2 diabetes.

Antimicrobial activity of Tunisian Euphorbia paralias L

Objective To examine the potential antimicrobial activity of Euphorbia paralias L. (Euphorbiaeae) leaves and stems extracts. Methods The antimicrobial activity was tested against six microbial strains: Escherichia coli ATCC 8739, Bacillus subtilis ATCC 6633, Salmonella enterica CIP 8039, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9027 and Candida albicans ATCC 90028 by two different methods, the disk method and the dilution method. Results Our results showed the important antimicrobial activity of the chloroform extract of the stems towards the majority of the strains by using both methods. Bacillus subtilis was the most sensitive strain (MIC = MBC = 15 μg/mL). Conclusion Thus, some extracts of Euphorbia paralias can be used in the treatment of infectious diseases caused by microbes.

Antibacterial, antioxidant, anti-cholinesterase potential and flavonol glycosides of Biscutella raphanifolia [Brassicaceae]

Different extracts of the aerial parts of Biscutella raphanifolia [Brassicaceae], which has not been the subject of any study, were screened for the phytochemical content, anti-microbial, antioxidant and anti-cholinesterase activities. We used four methods to identify the antioxidant activity namely, ABTS[*+], DPPH[*] scavenging, CUPRAC and ferrousions chelating methods. Since there is a relationship between antioxidants and cholinesterase enzyme inhibitors, we used two methods to determine the in vitro anti-cholinesterase activity by the use of the basic enzymes that occur in causing Alzheimer's disease: acetylcholinesterase [AChE] and butyrylcholinesterase [BChE]. The extracts were also tested in vitro antimicrobial activity against various bacteria. The phytochemical study of B. raphanifolia afforded four flavonol glycosides; namely, quercetin-3-O- beta -D-g1ucoside, quercetin-3-O-[beta -D-glucosyl[1[right wards]2]-O- beta -D-glucoside], quercetin-3- O-[beta -D-glucosyl[1[right wards]3]-O- beta -D-glucoside] and kaempferol-3-O-[beta -D-glucosyl[1[right wards]2]-[[6'''p-coumaroyl]- beta -D-glucoside], being isolated here for the first time from Biscutella raphanifolia and the genus. The ethyl acetate extract showed the highest activity in ABTS[*+], DPPH[*] and CUPRAC assays, while the petroleum ether extract demonstrated optimum efficiency metal chelating activity. The dicloromethane and petroleum ether extracts showed a mild inhibition against AChE and BChE. However, the petroleum ether extract showed a good antibacterial activity against the pathovars Enteropathogenic E. coli [EPEC], Enterotoxigenic E. coli [ETEC] and Enterococcus feacalis, whereas the Enterohemorrhagic E. coli [EHEC] strain was more sensitive to dichloromethane and n-butanol extracts

Etiology of acute diarrhea in tunisian children with emphasis on diarrheagenic escherichia coli: prevalence and identification of E.coli virulence markers

Diarrheal diseases can be caused by viral, bacterial and parasitic infections. This paper provides a preliminary image of diarrhea with regards to etiology and epidemiologic factors in Tunisian children less than five years of age. Overall, 124 diarrhoeal stools were collected from patients suffering from acute diarrhea and 54 stool samples from healthy children. All stools were examined for the presence of enteric pathogens. In diarrheagenic children, 107 pathogenic bacteria were isolated [12 Salmonella spp. [9.7%] and 95 diarrheagenic Escherichia coli strains [76.6%]: 29 enteroaggregative E.coli [EAEC] [23.4%], 15 enteroinvasive E.coli [EIEC] [12.1%], 17 enteropathogenic E.coli [EPEC] [13.7%], 26 enterotoxigenic E.coli [ETEC] [21%] and 2 enterohemoragic E.coli [EHEC] [1.6%]. However, in the control group, 23 pathogenic E.coli strains were isolated [42.6%] 8 EAEC [14.8%], 12 EIEC [22.2%] and 3 EPEC [5.5%]. Among diarrheagenic E.coli [DEC], only ETEC strains were significantly recovered from diarrheagenic children than from healthy controls [P < 0.0003]. Group A rotavirus was identified in 33.9% [n=42] of diarrheagenic children and in 11.1% among the control group [n=6]. Concerning norovirus, 8.9% [n=11] of the samples collected from diarrheagenic children and 9.2% [n=5] from the control group were positive. The prevalence of rotaviruses and Salmonella spp were also significantly higher in patients with diarrhea than in controls [P = 0.002 and P < 0.019, respectively]. Finally, enteropathogenic parasites [Entamoeba coli and cryptosporidium Oocystes] were isolated from 4.8% and 9.2% of diarrheagenic and control children, respectively. These results provide baseline data about the relative importance of different enteropathogens in Tunisian children

Evolutionary pattern of 5'-UTR of enteroviruses and primer update for the detection of enteroviral RNA in environmental samples

OBJECTIVE@#To study the recombination events among enterovirus strains and the development of specific primers for the detection of enteroviruses in environmental samples.@*METHODS@#Nucleotide sequence analysis of enteroviruses deposited in the international database GenBank (www.ncbi.nlm.nih.gov/Genbank) was conducted to develop specific primers for the detection of these viruses. The specificity and sensitivity of the method were tested using coxackievirus B3 strain Nancy, environmental isolate of human hepatitis A virus and human rotavirus strain WA. Seventy sewage samples were analyzed.@*RESULTS@#Enterovirus genome was detected in all positive samples. The genome of enterovirus was not detected in negative samples. The level of detection of these viruses was 10(2) TCID(50)/mL.@*CONCLUSIONS@#The development of new primers is an important issue for the detection of enteroviruses in the environment and the assessment of risk factors to human health.

[Resistance in gram negative bacteriae: what is the current situation?]

Emergence of antibiotic resistance put an end to the antibiotic miracle. According to recent review data, the number of cases of multiresistant bacteria, which are resistant to all antibiotics available, is increasing as well in the developed countries as in the developing countries. To face the emergence of these bacteria, it is necessary to evaluate the situation in Tunisian hospitals and act consequently. This review provide recent data on antibiotic resistance in Gram negative bacilli in Tunisian hospitals by focusing on some emergent resistances, which represent a daily challenge for the medical profession, such as extended spectrum beta-lactamases, carbapenem resistance, and fluoroquinolone resistance

[Detection of enteric viruses in wastewater of Monastir region by RT PCR method]

Wastewater frequently has been contaminated by enteric viruses, which can cause gastroenteritis, hepatitis, and other viral diseases. Since current water treatments do not ensure their complete removal and they become contaminants of the water environment. In order to monitor and assess the prevalence and the seasonal incidence of enteric viruses contaminating wastewater, a total of 93 samples were collected from the stations of Sayada-Lamta-Bouhjar and El Frina. The purpose of this study is to establish a rapid, sensitive and specific RT-PCR method using highly conserved primers to detect enteric viruses [caliciviruses, enteroviruses and hepatitis A viruses] circulating in the area of Monastir, during the period from October 2005 to July 2006. Our study shows that the caliciviruses were detected in 67.56%of the wastewater samples and present an essentially winter distribution with a specific peak in spring. The enteroviruses were detected in 35.13%of the samples tested and present a regular circulation during the year with a predominance in the summer and early fall. Finally, the presence of hepatitis A viruses was noted especially in winter in 10.81%of the wastewater samples. We notice that current wastewater treatment methods are sometimes not efficient to eliminate enteric viruses

In vitro antimicrobial activity of four ficus carica latex fractions against resistant human pathogens [antimicrobial activity of ficus carica latex]

Methanolic, hexanoi'c, chloroformic and ethyl acetate extracts of Ficus carica latex were investigated for their in vitro antimicrobial proprieties against five bacteria species and seven strains of fungi. The green fruit latex was collected from Chott Mariam Souse, Middle East coast of Tunisia. The antimicrobial activity of the extracts was evaluated and based respectively on the inhibition zone using the disc - diffusion assay, minimal inhibition concentration [MIC] for bacterial testing and the method by calculating inhibition percentage [1%] for fungi-inhibiting activities. The methanolic extract had no effect against bacteria except for Proteus mirabilis while the ethyl acetate extract had inhibition effect on the multiplication of five bacteria species [Enterococcus fecalis, Citobacter freundei, Pseudomonas aeruginosa, Echerchia coll and Proteus mirabilis]. For the opportunist pathogenic yeasts, ethyl acetate and chlorophormic fractions showed a very strong inhibition [100%]; methanolic fraction had a total inhibition against Candida albicans [100%] at a concentration of 500 micro g/ml and a negative effect against Cryptococcus neoformans. Microsporum canis was strongly inhibited with methanolic extract [75%] and totally with ethyl acetate extract at a concentration of 750 micro g/ml. Hexanoi'c extract showed medium results

Antibacterial and cytotoxic activity of the acetone extract of the flowers of salvia sclarea and some natural products

The aim of this study was to investigate the antibacterial and the cytotoxic activity of the acetone extract of the flowers of Salvia sclarea and of some natural products [sclareol, sclareolide and ambrox]. The antibacterial and the cytotoxic activity were determined by the dilution method. Sclareolide, ambrox and sclareol demonstrated a good antibacterial activity against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27950, Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212. The acetonic extract of the flowers of Salvia sclarea has a significant cytotoxic activity against Hep-2 cells

Etude de l'activite cytotoxique in vitro des derives du cyclopentanone

The cytotoxicity of 30 cyclopentanone derivatives was studied in vitro, in a clonogenic assay using murine leukemia LI 210. Results are compared to those obtained with reference medicaments. 17 derivatives exhibit activities against L1 210 cells.