| Autor: |
Sinze Metiave AA; Natural Products Chemistry Research Unit, Department of Chemistry, Faculty of Science, University of Dschang, Dschang, Cameroon., Tedonkeu AT; Natural Products Chemistry Research Unit, Department of Chemistry, Faculty of Science, University of Dschang, Dschang, Cameroon., Tamokou JD; Research Unit of Microbiology and Antimicrobial Substances, Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon., Nanfack ARD; Natural Products Chemistry Research Unit, Department of Chemistry, Faculty of Science, University of Dschang, Dschang, Cameroon., Matsuete-Takongmo G; Research Unit of Microbiology and Antimicrobial Substances, Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon., Kamtcha Wetadieu D; Natural Products Chemistry Research Unit, Department of Chemistry, Faculty of Science, University of Dschang, Dschang, Cameroon., Tsopmo A; Food Science Program, Department of Chemistry, and Institute of Biochemistry, Carleton University, Ottawa, Canada., Tene M; Natural Products Chemistry Research Unit, Department of Chemistry, Faculty of Science, University of Dschang, Dschang, Cameroon. |
| Abstrakt: |
Two new stigmastane steroids ( 1 and 2 ) were isolated from the methanol extract of the leaves of Vernonia glabra , together with seventeen known compounds ( 3-19 ) including one fatty acid, four triterpenoids, four steroids, one trinitropropanoyl glucoside, and seven flavonoids. The structures of compounds 1 and 2 were assigned based on their IR, NMR and MS data, and by comparison with literature values. The MeOH extract, its fractions and isolated compounds were subjected to in vitro antibacterial assay against two Gram-positive ( Staphylococcus aureus ATCC25923 and Streptococcus pneumoniae ATCC49619) and two Gram-negative ( Escherichia coli ATCC8739 and Klebsiella pneumoniae ATCC10031) bacteria, using broth microdilution method. The extract and fractions exhibited (16 ≤ MIC ≤ 512 μg/mL) antibacterial activities. The isolated and tested compounds were also active (16 ≤ MIC ≤ 128 μg/mL) against the four pathogenic bacteria, with compound 2 being the most active and E. coli , the most sensitive microorganism. |
