| Title: | Volatile compounds in the stem bark of Sclerocarya birrea (Anacardiaceae) possess antimicrobial activity against drug-resistant strains of Helicobacter pylori |
| Author(s): | Njume C; Afolayan AJ; Green E; Ndip RN; |
| Address: | "Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Fort Hare, Alice, South Africa" |
| DOI: | 10.1016/j.ijantimicag.2011.05.002 |
| ISSN/ISBN: | 1872-7913 (Electronic) 0924-8579 (Linking) |
| Abstract: | "The aim of this study was to isolate and identify phytochemicals with anti-Helicobacter pylori activity from the stem bark of Sclerocarya birrea. The plant crude extract was fractionated by silica gel column and thin layer chromatography techniques, initially with ethyl acetate (EA) and subsequently with a combination of ethyl acetate/methanol/water (EMW). Further fractionation and identification of the phytoconstituents was achieved by gas chromatography and mass spectrometry (GC/MS) analysis. The antimicrobial activity of the fractions and compounds was evaluated against five metronidazole- and clarithromycin-resistant strains of H. pylori as well as a reference strain ATCC 43526 using the microbroth dilution technique. Amoxicillin was included in the experiments as a positive control antibiotic. Of the 18 fractions collected, 16 demonstrated anti-H. pylori activity with 50% minimum inhibitory concentration (MIC(50)) values ranging from 310 mug/mL to 2500 mug/mL. Two of the fractions (EMW fraction 6 and EA fraction 1) revealed the presence of 5 and 24 compounds, respectively, representing 40.5% and 86.57% of the total composition. Most of the compounds were essential oils, with terpinen-4-ol being the most abundant agent (35.83%), followed by pyrrolidine (32.15%), aromadendrene (13.63%) and alpha-gurjunene (8.77%). MIC(50) ranges for amoxicillin, terpinen-4-ol and pyrrolidine were 0.0003-0.06 mug/mL, 0.004-0.06 mug/mL and 0.005-6.3 mug/mL, respectively. The inhibitory activities of terpinen-4-ol and pyrrolidine were similar to amoxicillin (P>0.05). Most of these compounds are being reported in this plant for the first time and may represent new sources of therapeutically useful compounds against H. pylori" |
| Keywords: | "*Anacardiaceae Anti-Bacterial Agents/chemistry/*pharmacology/therapeutic use Drug Resistance, Multiple, Bacterial Gastrointestinal Diseases/drug therapy Helicobacter Infections/drug therapy Helicobacter pylori/*drug effects/isolation & purification Humans;" |
| Notes: | "MedlineNjume, C Afolayan, A J Green, E Ndip, R N eng Research Support, Non-U.S. Gov't Netherlands 2011/07/15 Int J Antimicrob Agents. 2011 Oct; 38(4):319-24. doi: 10.1016/j.ijantimicag.2011.05.002. Epub 2011 Jul 14" |
