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The discovery of antibiotics more than 80 years ago has led to considerable improvements in human and animal health. Although antibiotic resistance in environmental bacteria is ancient, resistance in human pathogens is thought to be a modern phenomenon that is driven by the clinical use of antibiotics1. Here we show that particular lineages of methicillin-resistant Staphylococcus aureus—a notorious human pathogen—appeared in European hedgehogs in the pre-antibiotic era. Subsequently, these lineages spread within the local hedgehog populations and between hedgehogs and secondary hosts, including livestock and humans. We also demonstrate that the hedgehog dermatophyte Trichophyton erinaceiproduces two β-lactam antibiotics that provide a natural selective environment in which methicillin-resistant S. aureusisolates have an advantage over susceptible isolates. Together, these results suggest that methicillin resistance emerged in the pre-antibiotic era as a co-evolutionary adaptation of S. aureusto the colonization of dermatophyte-infected hedgehogs. The evolution of clinically relevant antibiotic-resistance genes in wild animals and the connectivity of natural, agricultural and human ecosystems demonstrate that the use of a One Health approach is critical for our understanding and management of antibiotic resistance, which is one of the biggest threats to global health, food security and development.

Tricin, one of the flavones present in edible Poaceae species, was shown to interfere with intestinal inflammatory-related carcinogenesis and suppress metastasis in colon cancer mice models. Those botanical foods and medicinal herbs which contain high content of tricin may be considered as health supplements for colon health. Hence, the present study aimed to identify and quantify the content of tricin in various medicinal herbs, edible botanicals and some agricultural by-products by LC-MS. A list of “top 10 tricin-rich botanicals/medicinal herbs” was built. From the results, the top three high tricin content botanicals are the dried culms of Triticum aestivum(wheat straw), dried culms of Oryza sativa(rice straw) and mature fruits of Imperata cylindrica. Furthermore, a simple, straightforward isolation method has been developed to isolate tricin from wheat straw which achieved 50% isolation rate (percentage yield of 0.05% w/w) with purity of not less than 98%.

The authentication of bamboo shoots found in the marketplace is complex because the chemical profile of processed and unprocessed material is different. During processing, heat derivatives of the potentially toxic cyanogenic glycoside taxiphyllin are produced. Here, we report the isolation and structure elucidation of the two major diarylbutenedinitrile derivatives, which are cisand transisomers of the rare 2,3-bis(4-hydroxyphenyl)but-2-enedinitrile from a commercial extract of bamboo shoots. These compounds, absent in fresh bamboo shoots, were produced by boiling the shoots of Bambusa vulgarisand were associated with a decrease in levels of taxiphyllin. Furthermore, (E)-2,3-bis(4-hydroxyphenyl)but-2-enedinitrile was quantified in all 16 of the commercial products tested. Its abundance was found to be highly variable, ranging from 1 to 3 mg/g in preserved bamboo shoots and from 10 to 160 mg/mL in commercial aqueous extracts. Of the 15 authenticated bamboo samples tested for taxiphyllin, it was found only in the shoots of B. vulgarisand Gigantochloa verticillata, which represent two edible bamboo species. Our results indicate that diarylbutenedinitriles can be used as markers for the authentication of boil-processed bamboo shoots obtained from taxiphyllin-containing edible species and organs.

Humans have been using biodiversity for hundreds of thousands of years, but at no time in our history has it been more crucial to accelerate our exploration of the useful properties of the species that inhabit the world around us.

Two new and seven known sesquiterpene compounds were isolated from an agar plate culture of Granulobasidium vellereum, isolated from a log of Ulmussp. The two new structures were elucidated with spectroscopic methods as an illudalane derivative, granulolactone (1), and a 15-norilludane, granulodione (9). The acaricidal and insecticidal activities of the isolated compounds were examined in vitro against two major horticultural pests, the two-spotted spider mite Tetranychus urticaeand the glasshouse thrips Heliothrips haemorrhoidalis, respectively.

Species of Aristolochiaare used as herbal medicines worldwide. They cause aristolochic acid nephropathy (AAN), a devastating disease associated with kidney failure and renal cancer. Aristolochic acids I and II (1and 2) are considered to be responsible for these nephrotoxic and carcinogenic effects. A wide range of other aristolochic acid analogues (AAAs) exist, and their implication in AAN may have been overlooked. An LC-MS- and 1H NMR-based metabolomic analysis was carried out on 43 medicinally used Aristolochiaspecies. The cytotoxicity and genotoxicity of 28 Aristolochiaextracts were measured in human kidney (HK-2) cells. Compounds 1and 2were found to be the most common AAAs. However, AA IV (3), aristolactam I (4), and aristolactam BI (5) were also widespread. No correlation was found between the amounts of 1or 2and extract cytotoxicity against HK-2 cells. The genotoxicity and cytotoxicity of the extracts could be linked to their contents of 5, AA D (8), and AA IIIa (10). These results undermine the assumption that 1and 2are exclusively responsible for the toxicity of Aristolochiaspecies. Other analogues are likely to contribute to their toxicity and need to be considered as nephrotoxic agents. These findings facilitate understanding of the nephrotoxic mechanisms of Aristolochiaand have significance for the regulation of herbal medicines.

Different negative ion electrospray (ES) source conditions are required to concentrate the ion current in [M–H]–for malonylated and non‐malonylated ginsenosides. However, both can be ionised optimally in a single liquid chromatography/mass spectrometry (LC/MS) analysis by employing switchable voltages in the post‐source ion optics of a quadrupole ion trap mass spectrometer. Coupled with automatic MS/MS scanning and post‐acquisition neutral loss data analysis, this method provides a means of profiling the malonylated and acetylated ginsenosides in ginseng extracts. Analyses revealed numerous malonylated ginsenosides that could be partially characterised by serial MS/MS experiments. The ratio of mRb1to other isomeric forms present and to mRb2and mRc appears to show consistent differences among Panax ginseng(Asian ginseng), P. quinquefolius(American ginseng) and P. notoginseng(Sanchi ginseng). The ratio of malonylated to non‐malonylated ginsenosides is reduced in the red form of Asian ginseng compared with the white form and there is a concomitant increase in the levels of the corresponding acetylated ginsenosides. The ability to analyse malonylated ginsenosides is an important contribution to the range of chemical characteristics that can be used to authenticate the different species of ginseng and will assist in quality control and standardisation. Copyright © 2002 John Wiley & Sons, Ltd.

Different negative ion electrospray (ES) source conditions are required to concentrate the ion current in [M–H]^– for malonylated and non-malonylated ginsenosides. However, both can be ionised optimally in a single liquid chromatography/mass spectrometry (LC/MS) analysis by employing switchable voltages in the post-source ion optics of a quadrupole ion trap mass spectrometer. Coupled with automatic MS/MS scanning and post-acquisition neutral loss data analysis, this method provides a means of profiling the malonylated and acetylated ginsenosides in ginseng extracts. Analyses revealed numerous malonylated ginsenosides that could be partially characterised by serial MS/MS experiments. The ratio of mRb1 to other isomeric forms present and to mRb2 and mRc appears to show consistent differences among Panax ginseng (Asian ginseng), P. quinquefolius (American ginseng) and P. notoginseng (Sanchi ginseng). The ratio of malonylated to non-malonylated ginsenosides is reduced in the red form of Asian ginseng compared with the white form and there is a concomitant increase in the levels of the corresponding acetylated ginsenosides. The ability to analyse malonylated ginsenosides is an important contribution to the range of chemical characteristics that can be used to authenticate the different species of ginseng and will assist in quality control and standardisation. Copyright © 2002 John Wiley & Sons, Ltd.

The Iranian species of Nepetawere investigated as part of a phylogenetic study of the genus. The relationships among species revealed the status of some taxa including three new species. The new species are recognized by differences in morphology as well as molecular characters. Nepeta balouchestanica, N. mahanensis, and N. hormozganicaare described as new and their relationships with closely related taxa discussed.

The internal transcribed spacers of nuclear ribosomal DNA (nrITS) from 43 species of Nepetaand representatives of closely related genera (Lallemantia, Dracocephalumand Agastache) and outgroups (Lavandula, Stachys, Newcasteliaand Prostanthera) were sequenced. Parsimony analysis indicated that Nepetais monophyletic and composed of five major monophyletic groups, most of which comprise species belonging to more than one section in previous classifications. These five clades are composed of: (1) sect. Spartonepeta; (2) sects. Macronepeta+ Spicatae; (3) sects. Nepeta+ Micranthaep.p. + Oxynepeta+ Schizocalyx+ Macrostegiae; (4) sects. Capituliferae+ Denudatae+ Micranthaep.p. + Micronepetap.p.; and (5) sect. Psilonepeta. The phylogenetic relationships among species of these groups are congruent with the distribution of some floral characters, including corolla shape, bract texture, color and pollen exine ornamentation.

Targeted liquid chromatography/serial mass spectrometry (LC/MS/MS) analysis, using a quadrupole ion‐trap mass spectrometer, permitted the detection of aristolochic acids I and II in crude 70% methanol extracts of multi‐component herbal remedies without any clean‐up or concentration stages. The best ionisation characteristics were obtained using atmospheric pressure chemical ionisation (APCI) and by including ammonium ions in the mobile phase. Limits of detection for aristolochic acids were influenced by the level of interference created by other components in the sample matrix. They were determined to be between 250 pg and 2.5 ng on‐column within a matrix containing compounds extracted from 2 mg of herbal remedy. With a herbal remedy that only permitted the higher limit of detection, this sensitivity was sufficient to detect the aristolochic acids extracted from 0.1% dry weight of Aristolochia manshuriensisincluded in the preparation. Copyright © 2002 John Wiley & Sons, Ltd.

Atmospheric pressure chemical ionisation (APCI) and electrospray (ES) are compared as ion sources in the analysis of polyhydroxyalkaloids (PHAs) by liquid chromatography mass spectrometry (LC-MS) and collision induced dissociation (CID) product ion spectra, from tandem mass spectrometry (MS-MS) experiments in a quadrupole ion trap, are reported for 12 naturally occurring PHAs. APCI was found to be a more useful source than ES, as APCI could be used to generate deprotonated molecule ions in negative mode and for some isomeric PHAs the negative CID product ion spectra were more diagnostic than the positive product ion spectra. On-column detection limits were also approximately 32 times lower by positive APCI than ES. The work provides data that will facilitate screening and characterisation of this group of important natural products in plant and fungal extracts.

Direct MS analysis, utilizing first‐order MS and subsequent MS2and MS3product ion analyses, is shown to provide a rapid means of characterizing polyhydroxyalkaloid glycosides and aglycones in aqueous methanol plant extracts that have been crudely purified on ion exchange resin. Analysis of species known to synthesize polyhydroxyalkaloids resulted in the discovery of the first diglycosides of these compounds. These were detected in Omphalea diandraand Syzygium oleosum. A monoglycoside was also detected as a minor component in Castanospermum australe. Copyright © 1999 John Wiley & Sons, Ltd.

Investigations of the antifeedant mode of action of azadirachtin and four synthetic analogues, 22,23-dihydroazadirachtin, 3-tigloylazadirachtol, 11-methoxydihydroazadirachtin and 22,23-bromoethoxydihydroazadirachtin have revealed that both polyphagous and oligophagous insects are behaviourally responsive to azadirachtin, with the most responsive species being able to differentiate extremely small changes in the parent molecule. In Lepidoptera the antifeedant response is correlated also with increased neural activity of the chemoreceptors. When locusts are treated on crop plants, the antifeedant and physiological actions of azadirachtin and analogues work in concert and result in feeding deterrence, growth and moulting aberrations and mortality with the same order of potency as for antifeedancy. Specific binding studies using [³H]dihydroazadirachtin carried out on locust testes and Spodoptera Sf9 cells have shown that the competitive binding of the different analogues of azadirachtin to these binding sites occurs in a similar order of potency to that found with antifeedant and IGR bioassays. This suggests a causal link between specific binding to membrane proteins and the ability of the molecule to exert biological effects. © 1998 Society of Chemical Industry

A crudely purified polyhydroxyalkaloid (PHA) extract of Hyacinthoides non‐scripta(Hyacinthaceae) was studied by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/sequential mass spectrometry (LC/MSn) and direct infusion atmospheric pressure chemical ionisation‐mass spectrometry (APCI‐MS) to determine the best method for screening plant extracts for PHAs. Direct infusion was determined to be the technique of choice to carry out rapid screening, whereas LC/MS has the potential to reveal isomeric compounds with appropriate high performance liquid chromatography (HPLC) separation, and we report here a successful HPLC separation of underivatised PHAs in a crude extract. The requirement to derivatise PHAs for GC/MS analysis was found to confuse screening due to the formation of multiple derivatives. Also, the electron ionization (EI) mass spectra were of limited diagnostic value and GC/MS failed to detect high molecular weight PHA derivatives such as those of PHA‐diglycosides. Two glycosides not previously reported in Hyacinthaceae were detected by direct infusion APCI‐MS. Copyright © 1999 John Wiley & Sons, Ltd.

Direct MS analysis, utilizing first-order MS and subsequent MS² and MS³ product ion analyses, is shown to provide a rapid means of characterizing polyhydroxyalkaloid glycosides and aglycones in aqueous methanol plant extracts that have been crudely purified on ion exchange resin. Analysis of species known to synthesize polyhydroxyalkaloids resulted in the discovery of the first diglycosides of these compounds. These were detected in Omphalea diandra and Syzygium oleosum. A monoglycoside was also detected as a minor component in Castanospermum australe. Copyright © 1999 John Wiley & Sons, Ltd.

A crudely purified polyhydroxyalkaloid (PHA) extract of Hyacinthoides non-scripta (Hyacinthaceae) was studied by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/sequential mass spectrometry (LC/MSⁿ) and direct infusion atmospheric pressure chemical ionisation-mass spectrometry (APCI-MS) to determine the best method for screening plant extracts for PHAs. Direct infusion was determined to be the technique of choice to carry out rapid screening, whereas LC/MS has the potential to reveal isomeric compounds with appropriate high performance liquid chromatography (HPLC) separation, and we report here a successful HPLC separation of underivatised PHAs in a crude extract. The requirement to derivatise PHAs for GC/MS analysis was found to confuse screening due to the formation of multiple derivatives. Also, the electron ionization (EI) mass spectra were of limited diagnostic value and GC/MS failed to detect high molecular weight PHA derivatives such as those of PHA-diglycosides. Two glycosides not previously reported in Hyacinthaceae were detected by direct infusion APCI-MS. Copyright © 1999 John Wiley & Sons, Ltd.

Two diterpenoids have been isolated from Scutellaria rubicunda subsp. linneana : (11 S ,13 S ,15 R and S , 16 R ,19 S )-6 α -acetoxy-19-tigloyloxy-2 α ,19;4 α ,18;11,16;15,16-tetraepoxy-neo-clerodan-15-ol (scutecyprol B) and (11 S ,13 S ,15 R and S , 16 R ,19 S )-6 α -acetoxy-2 α ,19;4 α ,18;11,16;15,16-tetra-epoxy-neo-cleroda-15,19,diol (scutalbin C). Both compounds were tested for antifeedant activity against larvae of some species of Lepidoptera. Scutecyprol B shows potent activity at 100 ppm.

Three acylated iridoid glycosides (E)‐6‐O‐(2″, 4″‐diacetyl‐3″ ‐O‐p‐methoxycinnamoyl)‐α‐L‐rhamnopyranosyl catalpol (scopolioside A) (1), (E)‐6‐O‐(2″‐acetyl‐3″, 4″‐di‐O,O‐p‐methoxycinnamoyl)‐α‐L‐rhamnopyranosyl catalpol (scrophuloside A4) (2) and (E)‐6‐O‐(2″,3″‐diacetyl‐4″‐O‐p‐methoxycinnamoyl)‐α‐L‐rhamnopyranosyl catalpol (scrovalentinoside) (3) have been isolated from the dried seed pods of Scrophularia nodosaby HPLC. Their structures were determined by 1D and 2D NMR, UV/Vis and mass spectroscopy and by comparison with published data. All three compounds were shown in vitroto stimulate the growth of human dermal fibroblasts. The effect was negatively dose‐dependent for 2and 3for which fibroblast growth stimulation was highest at 0.78 μg/mL but was not significantly different from the control at 100 μg/mL. The presence of these compounds in the mature seed pods may explain the ethnobotanical use of this plant in Europe for healing wounds. Copyright © 2002 John Wiley & Sons, Ltd.

Three acylated iridoid glycosides (E)-6-O-(2", 4"-diacetyl-3" -O-p-methoxycinnamoyl)-α-L-rhamnopyranosyl catalpol (scopolioside A) (1), (E)-6-O-(2"-acetyl-3", 4"-di-O,O-p-methoxycinnamoyl)-α-L-rhamnopyranosyl catalpol (scrophuloside A4) (2) and (E)-6-O-(2",3"-diacetyl-4"-O-p-methoxycinnamoyl)-α-L-rhamnopyranosyl catalpol (scrovalentinoside) (3) have been isolated from the dried seed pods of Scrophularia nodosa by HPLC. Their structures were determined by 1D and 2D NMR, UV/Vis and mass spectroscopy and by comparison with published data. All three compounds were shown in vitro to stimulate the growth of human dermal fibroblasts. The effect was negatively dose-dependent for 2 and 3 for which fibroblast growth stimulation was highest at 0.78 μg/mL but was not significantly different from the control at 100 μg/mL. The presence of these compounds in the mature seed pods may explain the ethnobotanical use of this plant in Europe for healing wounds. Copyright © 2002 John Wiley & Sons, Ltd.

Phytochemical investigation of the acetone extract of the aerial parts of Onopordum illyricumL. afforded five known sesquiterpenoids: compounds 3 and 4 already isolated from O. illirycum, and 8α-[4′-hydroxymethacryloyloxy]-sonchucarpolide (1), 8α-[4′-hydroxymethacryloyloxy]-4-epi-sonchucarpolide (2) and 8-(4′-hydroxymethacryloyl)-dehydromelitensin (5), not previously detected in this species. Compounds 4 and 5 showed moderate antifeedant activity against larvae of Spodoptera littoralis.

A total of 16 phenolic compounds, including one new and five known N-cinnamoyl phenylethylamides, one new pyrrole alkaloid named portulacaldehyde, five phenylpropanoid acids and amides, and derivatives of benzaldehyde and benzoic acid, were isolated and identified from a polar fraction of an extract of Portulaca oleracea. Their structures were determined through spectroscopic analyses.

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Seven guaianolides were isolated from the acetone extract of the aerial parts of Centaurea hololeuca Boiss. The antifeedant activity of the natural compounds (1–7) and of four chloro derivatives (8–11), synthesized from repin (1) and janerin (3) were tested against larvae of Spodoptera littoralis. Cebellin J (6) and chlorojanerin (11) showed significant antifeedant activity at 100 ppm, whereas at this concentration cebellin G (4) and 15-deschloro-15-hydroxychlorojanerin (7) stimulated feeding. Cebellin G (4) stimulated larvae of S. littoralis to feed at low concentration, but deterred feeding at high concentrations. The addition of chlorine to repin (1) resulted in an increase in antifeedant activity.

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