title: An acylated phloroglucinol with antimicrobial properties from Helichrysum caespititium.
abstract: A new acylated form of a phloroglucinol with significant antimicrobial properties was isolated by bioactivity guided fractionation from Helichrysum caespititium (Asteraceae). The structure elucidation, and conformation of the new phloroglucinol, 2-methyl-4-[2',4',6'-trihydroxy-3'-(2-methylpropanoyl) phenyl]but-2-enyl acetate, was established by high field NMR spectroscopic and MS data. The compound inhibited growth of Bacillus cereus, B. pumilus, B. subtilis and Micrococcus kristinae at the very low concentration of 0.5 microg/ml and Staphylococcus aureus at 5.0 microg/ml. Six fungi tested were similarly inhibited at low MICs, Aspergillus flavus and A. niger (1.0 microg/ml), Cladosporium chladosporioides (5 microg/ml), C. cucumerinum and C. sphaerospermum (0.5 microg/ml) and Phylophthora capsici at 1.0 microg/ml.
authors.affiliation: Department of Botany, University of Pretoria, South Africa.
authors.forename: A D
authors.initials: AD
authors.lastname: Mathekga
authors.forename: J J
authors.initials: JJ
authors.lastname: Meyer
authors.forename: M M
authors.initials: MM
authors.lastname: Horn
authors.forename: S E
authors.initials: SE
authors.lastname: Drewes
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry* / Q000302:isolation & purification; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification; D019659:Asteraceae / Q000737:chemistry*; D015169:Colony Count, Microbial; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010696:Phloroglucinol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D013329:Structure-Activity Relationship
chemical_list: C405013:2-methyl-4-(2',4',6'-trihydroxy-3'-(2-methylpropanoyl)phenyl)but-3-enyl acetate; D000890:Anti-Infective Agents; D000935:Antifungal Agents; D010696:Phloroglucinol