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The antimycobacterial components of hops ( Humulus lupulus ) and their dereplication
Author(s) -
Stavri Michael,
Schneider Ruth,
O'Donnell Gemma,
Lechner Doris,
Bucar Franz,
Gibbons Simon
Publication year - 2004
Publication title -
phytotherapy research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.019
H-Index - 129
eISSN - 1099-1573
pISSN - 0951-418X
DOI - 10.1002/ptr.1527
Subject(s) - humulus lupulus , antimycobacterial , chemistry , linoleic acid , oleic acid , palmitic acid , chromatography , fatty acid , food science , organic chemistry , biochemistry , mycobacterium tuberculosis , medicine , tuberculosis , pathology , pepper
Bioassay‐guided fractionation of a hexane extract of strobile hops ( Humulus lupulus ) was undertaken to isolate and characterize the antimycobacterial constituents using the fast‐growing mycobacterial species Mycobacterium fortuitum . Activity was associated with a low polarity fraction and 1 H NMR spectra indicated the presence of a fatty acid mixture with unsaturated components. GC‐MS of the derivatives indicated the presence of palmitic, stearic and oleic acids with small quantities of lignoceric, arachidic, behenic and linoleic acids. These compounds were assessed against M. fortuitum and all saturated fatty acids were inactive at concentrations greater than 256 µg/ml, whereas the unsaturated fats oleic and linoleic acids displayed minimum inhibitory concentrations of between 4 and 16 µg/ml against the fast‐growing species tested. The widespread occurrence of these components could render screening for antimycobacterials from natural sources highly problematic without adequate dereplication. We propose that GC‐MS of derivatised components of lipophilic extracts be a rst step before any antimycobacterial bioassay‐guided study, as this technique is the method of choice for dereplication of fatty acids. Copyright © 2004 John Wiley & Sons, Ltd.