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A proposed standard extraction and HPLC analysis method has been used to measure typical levels of various phenolic compounds in the medicinally used Echinacea species. Chicoric acid was the main phenolic in E. purpurea roots (mean 2.27% summer, 1.68% autumn) and tops (2.02% summer, 0.52% autumn), and echinacoside was the main phenolic in E. angustifolia(More)
The factors affecting oil yield and quality of essential oils from Dalmatian sage (Salvia officinalis L.) are analyzed. Distillations of oils from individual plants and GC analyses revealed the presence of three chemotypes with different proportions of alpha- and beta-thujone (alpha/beta 10:1, 1.5:1, and 1:10). Different accessions could also be classified(More)
A series of acylated phloroglucinols and triketones was synthesized and tested for activity against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecalis (VRE) and multi-drug-resistant Mycobacterium tuberculosis (MDR-TB). A tetra-methylated triketone with a C12 side chain was the most active compound (MIC of around(More)
Red-pigmented leaf margins are common, but their functional significance is unknown. We hypothesized that red leaf margins reduce leaf herbivory by signalling to herbivorous insects the presence of increased chemical defences. Leaves were collected from a natural population of Pseudowintera colorata. Margin size, herbivory damage, anthocyanin content and(More)
A rapid extraction, clean-up and RPLC procedure suitable for routine quantitative analyses of sesquiterpene lactones (SLs) in Arnica montana is described. Seven SLs were isolated of which tigloyl and methacryloyl esters of helenalin made up over 50 % of the total. This method was applied to analyses of replicated samples of different flower parts, different(More)
Rapid quantitative near-infrared Fourier transform Raman analyses of the key phytonutrients in carrots, polyacetylenes and carotenoids, are reported here for the first time. Solvent extracts of 31 carrot lines were analyzed for these phytonutrients by conventional methods, polyacetylenes by GC-FID and carotenoids by visible spectrophotometry. Carotenoid(More)
The bioactivity-directed isolation of deoxylapachol [I] from a New Zealand brown alga, Landsburgia quercifolia, is described. Compound I was active against P-388 leukemia cells (IC50 0.6 microgm/ml) and was also antifungal. 1,4-Dimethoxy-2-(3-methyl-2-butenyl)-naphthalene [3] was the major low polarity component of extracts of this seaweed, which also(More)
We evaluated the potential of apple to reduce inflammation. Phenolic compounds and triterpenes were analyzed in 109 apple cultivars. Total phenolics ranged from 29 to 7882 μg g(-1) of fresh weight (FW) in the flesh and from 733 to 4868 μg g(-1) FW in the skin, with flavanols including epicatechin and procyanidins as major components. Ursolic (44.7 to 3522(More)
Fast MS techniques have been applied to the analysis of sulfur volatiles in Allium species and varieties to distinguish phenotypes. Headspace sampling by proton transfer reaction (PTR) MS and surface sampling by desorption electrospray ionization (DESI) MS were used to distinguish lachrymatory factor synthase (LFS)-silenced (tearless; LFS-) onions from(More)
The triketone chemotype of manuka, Leptospermum scoparium (Myrtaceae), is commercially important because of its antimicrobial activity. Oils from 36 individual plants on the East Cape of New Zealand all showed similar high triketone contents (>20% total triketones) with little seasonal variation. Analyses of oils from 261 individual manuka plants collected(More)