Abstract

IN VITRO ANTIBACTERIAL ACTIVITY OF THE METHANOLIC AND ETHANOLIC EXTRACT OF INULA VISCOSA USED IN MOROCCAN TRADITIONAL MEDICINE

Khadija Laghrifi¹, Mostafa El Idrissi¹, Youssef Makoudi², Rachad Alnamer^{3, 4, 5}*

¹Laboratory of Organic Chemistry, Faculty of Sciences, My Ismail University, Meknes,Morocco.

²Laboratory Tafilalet of Medical Analyses, Meknes, Morocco.

³Laboratory of Biochemistry and Immunology, Department of Biology, Faculty of Science,Mohammed V Agdal University, Agdal, Rabat, Morocco.

⁴Laboratory of Pharmacology and Toxicology, Faculty of Medicine and Pharmacy,University Mohammed V Souissi, Rabat, Morocco.

⁵Departement of Pharmacology, University of Thamar, Yemen.

ABSTRACT

Inula viscosa (Dittrichia viscosa L.) had been reported in traditional medicine, to exhibit antimicrobial properties. Therefore, this study is aimed at determining the antibacterial activity of I. viscosa leaves and flowers against pathogenic microorganisms by determination the minimal inhibitory concentration and to serve as criteria to recommend the ethno pharmacological uses of the plant. Plant leaves and flowers were dried, powdered and extracted by cold maceration with methanol and ethanol for 48h. The extracts were screened against 24h broth culture of bacteria seeded in Muller Hinton Agar at concentration 5000 to 19μg/ml in sterile distilled water and incubated at 37°C, for 18h and measuring the inhibition zone diameter (IZD). Minimum inhibitory concentrations (MICs) against Gram-positive bacteria and Gramnegative bacteria were determined for the methanolic and ethanolic extracts of Inula viscosa. The ethanolic extract showed pronounced antibacterial than the aqueous extract against all of the tested microorganisms. Methanolic extract inhibited with minimal inhibitory concentration of 78, 78, 156, 156, 156, 312, 312, 312, 312, 312, 312, 625, 625, 625, 1250 and 2500μg/ml against Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli1, Escherichia coli17, Klebsiella oxytoca, Escherichia coli12, Escherichia coli15, Escherichia coli16, Providencia stuartii, Salmonella paratyphi A, Serratia marcescens, Acinetobacter baumannii, Pseudomonas aeruginosa, Salmonella paratyphi B, Citrobacter freundii, Escherichia coli14, Escherichia coli13, respectively, while the methanolic extract inhibited with minimal inhibitory concentration of 19, 39, 39, 39, 39, 78, 78, 78, 78, 78, 78, 78, 156, 156, 156, 156, 156, 156, 312 and 625μg/ml against Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli1, Escherichia coli17, Salmonella paratyphi A, Escherichia coli12, Escherichia coli15, Acinetobacter baumannii, Salmonella paratyphi B, Citrobacter freundii, Providencia stuartii, Escherichia coli14, Escherichia coli13, Klebsiella oxytoca, Pseudomonas aeruginosa, Edwardsiella tarda, Streptococcus feacalis, respectively. In conclusion, the extract of Inula viscosa contains some major bioactive compounds that inhibit the growth of microorganisms thereby proving very effective as alternative source of antibiotics. Our results support the ethno-pharmacological uses of this plant in folk medicine and could provide useful data for the utilization of this extracts in pharmaceutical, cosmetic and food industries.

Keywords: Inula viscosa, minimal inhibitory concentration, antibacterial screening, bacterial