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Plantamajoside is a bioactive caffeic acid derivative, a dihydroxyphenethyl glucoside in the group of polyphenolic compounds. It is one of the principal caffeic acid glycoside in the Plantago Digitalis, Hemiphragma, Lagotis, Picrorhiza, Rehmannia, Veronica, Wulfeniopsis and Wulfenia genera within the Plantaginaceae family. This compound is also present in the genera Aeschynanthus and Chirita of the Gesneriaceae family and the genus Boschniakia of the Orobanchaceae family. Plantamajoside is present in the greatest concentrations in roots of young plants, but it is also found in seeds, flower stalks, stems, leaves, in vivo cultivated plant cells and transgenic root cultures. Plantamajoside is used as a biomarker in chemotaxonomical studies, and is a compound with numerous biological applications and considerable pharmacological potential. It is a protective agent against ultra-violet light in plants and acts as antioxidant agent with very low toxicity. In addition, plantamajoside can also be industrially synthesized. This review aims to give an overview of plantamajoside in various plantago species as well as its potential as a biomarker and as a new drug compound.

Summary Two simple and rapid methods for early detection of the effects of herbicides using two different groups of plant biomarkers are presented. The methods are based on High Performance Planar Chromatography (HPPC) and have been developed as field-tests (Herbicide Weed Response test (HWR-Test ® ). Phytochemical changes can be detected before any morphological changes are visible on the plants. These changes are defined as biomarkers and can be detected by HPPC-screening. After overall identification of the phytochemical biomarker pattern by HPPC-screening, two different biomarker groups, carbohydrates and amino acids, were detected using modified HPPC reagents for color reactions. The color reactions of the two biomarker groups four days after exposure were correlated with biomass reduction 21 days after exposure in extracts of unexposed plants and plants exposed to herbicides. The method can, thus, be used as an early indicator for predicting the extent of the effects of herbicides on plants.

Enchytraeids are small soil living oligochaete worms with high sensitivity to low soil moisture. The effects of acute and chronic desiccation on survival and reproduction were determined in Enchytraeus albidus and Enchytraeus crypticus. Further, effects of acute drought stress on the water balance physiology and accumulation of osmolytes were investigated in E. albidus. Survival of E. crypticus and E. albidus was significantly influenced by exposure time. Reproduction was much more sensitive to desiccation than survival and was significantly reduced from -0.06 bar, which was surprising because no dehydration or change in the body fluid osmolality of E. albidus occurred until much harsher drought regimes occurred. The body fluid osmolality of E. albidus was relatively high, about 500 mOsm. Congruent with this no water loss or changes in osmotic pressure occurred until equivalent or higher water potential values of the environment were reached. Two osmolytes, glucose and alanine, were up-regulated in drought exposed E. albidus. Even though enchytraeids display moderate physiological protection to rapid changes in soil moisture (by having a high osmotic pressure) in the short term, populations subjected to long-term drought stress can be severely reduced even under moderate drought levels.

Microcosm and mesocosm studies evidence that pyrethroid insecticides may have a severe effect on zooplankton populations. The effect may cascade to phytoplankton communities and thus worsen the impact of eutrophication and algal blooms. In natural freshwater systems, pyrethroids are usually only detectable during the first 24 h after application to adjacent areas, a period too short for mesocosm and microcosm studies to reveal potential effects. In this study we compare the effects of environmentally realistic concentrations of the pyrethroid cypermethrin on: (i) the swimming ability of Daphnia magna; (ii) the feeding efficiency, measured as the content of chlorophyll pigments in the gut; and (iii) the total body carbohydrate content. The latter two were measured using a newly developed high performance planar chromatography (HPPC) system. Sublethal effects on the gut content of chlorophyll pigments, carbohydrate substances and the swimming ability of D. magna were observed at nominal concentrations between 0.05 and 0.6 microg cypermethrinL(-1), which lies within the concentration range occurring in freshwater systems after pesticide application. In addition, the content of chlorophyll pigments in the gut was significantly reduced (>50%) after only 6 h of exposure to 0.1 microg cypermethrinL(-1). Most of the D. magna had recovered 3 days after exposure doses lower than 0.2 microg cypermethrinL(-1). We conclude that HPPC analysis of the gut content of chlorophyll pigments was the most sensitive endpoint of our study due to its capacity to detect significant reductions in feeding within hours of exposure to environmentally realistic concentrations of cypermethrin.

A new and simplified method for extraction of ergosterol (ergosta-5,7,22-trien-3beta-ol) from fungi in soil and litter was developed using pre-soaking extraction and paraffin oil for recovery. Recoveries of ergosterol were in the range of 94-100% depending on the solvent to oil ratio. Extraction efficiencies equal to heat-assisted extraction treatments were obtained with pre-soaking extraction. Ergosterol was detected with thin-layer chromatography (TLC) using fluorodensitometry with a quantification limit of 8 ng. Using visual evaluation of images of TLC plates photographed in UV-light the quantification limit was 16 ng.

Summary 1. Physiological and biochemical responses to desiccation were studied in two species of hygrophilic Collembola, Folsomia fimetaria L. and Protaphorura armata Tullberg. The temporal changes in water content, body fluid osmotic pressure, and accumulation of sugars and polyols during desiccation stress, equivalent to severe soil drought are reported. 2. Both species initially lost about 50% of their initial content of osmotically active water. Within 7 days F. fimetaria had re-established their preliminary water content by absorbing water vapour from the atmosphere. Protaphorura armata also significantly increased their water content over the following 10 days. 3. Both species were able to resume their hyperosmotic status relative to the desiccating environment they were placed in. The accumulation of myo-inositol and two other unidentified compounds ( F. fimetaria ) and trehalose ( P. armata ) made an important contribution to this phenomenon. 4. These results suggest that water vapour absorption by accumulation of sugars and polyols may be widespread in soil-dwelling Collembola.

The optimal conditions were established for extraction of paralytic shellfish toxins from a Danish clone of Alexandrium tamarense using extraction with acetic acid and HCl in the concentration range 0.01–1.0 N. Physical destruction of the cells was investigated microscopically to select the most efficient extraction procedure.

Batch cultures of the dinoflagellate Alexandrium ostenfeldii (Paulsen) Balech et Tangen were characterized by an exponential growth phase ending after 10 days. Three different paralytic shellfish poison (PSP) toxin patterns (A, B, and C) occurred at days 3, 6 and 10, respectively. The main toxins in pattern A were: 53% GTX6, 26% C4, 17% GTX5; B: 62% GTX4, 17% GTX6, 16% C3; C: 31% GTX4, 28% GTX6, 26% C4, 13% C3. Batch cultures (with identical pattern A) were challenged (elicted) on day 3 with various organic compounds and extracts of Alexandrium tamarense . After elicitation each toxin concentration changed on both day 6 and 10. A causal relation between properties of the elicitor and the resulting toxin pattern could not be established. It is proposed that toxins responding with small relative standard variations from the mean concentration (STX, neoSTX, GTX3, GTX4, GTX6 and C3) are characteristic for the batch culture. Toxins with high variability (GTX1, GTX2, GTX5, C2 and C4) change concentration as a result of stress provoked by the elicitors. The toxicity (estimated from standard values) of some elicited cultures had increased by a factor of 4 on day 10 indicating that stimulation of blooms of A. ostenfeldii may have substantial consequences regarding the problem of paralytic shellfish poisoning.

The four known phenolic compounds, 3,4-dihydroxyphenethyl alcohol-6- O -caffeoyl-β- d -glucoside, acteoside (verbascoside), plantaginin and plantamajoside, and a new phenylpropanoid glycoside, hellicoside, were isolated from the aerial parts of Plantago asiatica , which is used in oriental medicine ‘Plantaginis Herba’. The structure of hellicoside was deduced from chemical and spectral evidence to be 3,4,7-trihydroxy-β-phenethyl- O -β- d -glucopyranosyl-(1 → 3)-4- O -caffeoyl-β- d -glucopyranoside. Plantamajoside and hellicoside showed high inhibition of cyclic AMP phosphodiesterase and 5-lipoxygenase. Acteoside showed high inhibition of lens aldose reductase.

Metabolic effects in rapeseed ( Brassica napus L.) seedlings after root exposure to sublethal concentrations of glyphosate were examined in order to evaluate the possibilities of using a response pattern in plants as a measure of exposure to glyphosate through the growth media, more sensitive than the well-known biomarker shikimate. Rapeseed seedlings were grown in hydroponic nutrient solutions containing varying sublethal concentrations of glyphosate (1–50 μM). After 9 days of glyphosate exposure, the shoots of the seedlings were analysed with respect to the effects on selected metabolites downstream from the primary affected metabolite shikimate, which accumulated linearly in response to glyphosate exposure (from 0 to ∼126 μmol/g DW). The selected metabolites analysed, comprising the free amino acids, and the glucosinolates derived therefrom, showed complex patterns in response to glyphosate exposure. Most noteworthy was though that they responded at the lowest concentrations of exposure to glyphosate (1 μM), where no visual effects, decrease in shoot DW or shikimate could be detected, indicating that a biomarker response more sensitive than that of shikimate can be established for plants exposed to glyphosate.

Summary Dose-splitting or reduced dose repeat application, i.e. the application of a herbicide twice to the same plant, is likely to become a more common scenario in future, if farmers adopt the use of novel techniques for prediction of herbicide efficacy shortly after application. Fourteen pot experiments were conducted to study whether graminicides applied to annual grass weeds as dose-splitting treatments were as effective as single applications. The influence of time interval between applications and the ratio of the doses of the two applications were studied. Two statistical approaches were applied: comparison of the ED90 of the single treatments and a joint action model. The study revealed that flupyrsulfuron, iodosulfuron, sulfosulfuron, clodinafop and glyphosate could be applied as repeat treatments with up to 14 days’ interval between the two applications without loss of activity. In some experiments, particularly with iodosulfuron, dose-splitting enhanced herbicide performance. By contrast, prosulfocarb responded adversely, most likely due to the pronounced impact of weed growth stage on the activity of this herbicide. The ratio of the doses and the timing between the two applications had no significant influence on herbicide responses. The results of the present studies showed that even if a reduced dose of a graminicide results in an unsatisfactory control and it is necessary to re-spray, the overall use of herbicide will not increase, if methods are available that can predict the efficacy of a herbicide application within the first 1–2 weeks after application.

International audience; A new, easy, rapid and relatively inexpensive method using microscopy has been developed for the detection of herbicide effects in leaves of grass weed species displaying no visual signs of damage. The method has potential to be used as a tool to indicate future death of grass species due to herbicide exposure by observing phytochemical effects, i.e. early-warning effects. In the present study, Apera spica-venti(L.) Beauv., Bromus hordeaceus L., Alopecurus myosuroides Huds., Lolium perenne L. and Poa annua L. were exposed to lethal rates of four herbicides with different mode of action. The herbicides investigated were the thiocarbamate: prosulfocarb, the sulfonylurea: iodosulfuron, the aryloxyphenoxypropionate: fenoxaprop-P-ethyl and the organophosphate glyphosate. Autofluorescence of leaves was studied under a microscope using ultraviolet and blue light. The fluorescence of leaves treated to enhance flavonoids was also examined. To confirm the results, microspectrofluorometry was performed. Effects indicating future death of the grasses were observed in visually healthy leaves following treatment with prosulfocarb, glyphosate and iodosulfuron. No changes were detected following treatment with fenoxaprop-P-ethyl. After exposure to glyphosate or iodosulfuron, changes in the content of flavonoids and other compounds with a conjugation system and rigid structure and a decrease in the content of chlorophyll were detected in the leaves. Prosulfocarb treatment resulted in changes in the content of flavonoidsand other compounds with a conjugation system and rigid structure and an increase in the content of chlorophyll in the leaves. The results obtained from microspectrofluorometry indicated that exposure to prosulfocarb caused a reduction in the flavonoids quercetin, naringenin and/or naringin.

Eleven free amino acids were identified in the grass weed loose silky-bent (Apera spica-venti) after exposure to four rates of the thiocarbamate herbicide prosulfocarb. A new HPTLC method was developed for quantification of amino acids in raw plant extracts. A pattern of significant changes in the content of glutamine, glycine, alanine, and proline due to exposure were detected. The content of all four amino acids increased at increasing exposure rates. Quantitative analyses 7 and 21 days after herbicide application showed that over time the amount of proline increased, the alanine and glycine content decreased, and that at high exposure rates the amount of glutamine increased. Visual effects were evaluated and the biomass was measured. The visual symptoms increased and the biomass decreased with increasing exposure rates. A significant correlation between the changes in the content of the four amino acids and the visual effects and the biomasses were found.

1 Department of Terrestrial Ecology, National Environmental Research Institute, Vejlsovej 25, Post Office 314, DK-8600 Silkeborg, Denmark 2 Danish Institute of Agricultural Sciences, Department of Crop Protection, Flakkebjerg, DK-4200 Slagelse, Denmark 3 University Montpellier 1, Faculty of Pharmacy, Laboratory of Botany, Phytochemistry and Mycology, 15, Avenue Charles-Flahault, FR-34093 Montpellier Cedex 5, France

The seasonal variation and distribution of rosmarinic acid and caffeic acid in leaves and roots-rhizomes of eelgrass (Zostera marina L.) were examined by using an isocratic high-performance liquid chromatography (HPLC) method developed for separation and quantification of the two phenolic compounds in crude plant extracts. The variation in phenolic content was compared to variations in tissue concentrations of nitrogen and phosphorus, in order to test a proposed relationship between nutrient status of the plant and biosynthesis of the secondary metabolites. The concentration of rosmarinic acid (not previously found in a monocotyledon) plus caffeic acid ranged from 0.4 to 19.2 mg (g dw)-1 with rosmarinic acid being the quantitatively most important component. The figures represent low estimates due to loss of phenolics during sample preparation. High phenolic concentrations occurred in spring and low concentrations during summer and fall, and the highest concentrations were most often found in the...

The structure of plantamajoside, a phenylpropanoid glycoside isolated from Plantago major subs major , is deduced from chemical, spectral and other physical evidence, to be 3,4-dihydroxy-β-phenethyl- O -β- d -glucopyranosyl-(1 →3)-4- O -caffeoyl-β- d -glucopyranoside. The Minimum Inhibitory Concentration value has been evaluated for seven plant pathogenic bacteria and for E. coli (ML 30) and S. aureus (502 A) after preliminary investigations by the agar diffusion method.

Seven caffeic acid derivatives were tested for their activity against two plant-pathogenic fungi and seven plantpathogenic bacteria. A determination of minimum inhibitory concentration (MIC) in solid media was used for the fungi, and for the bacteria agar diffusion, as well as determintion of the MIC in liquid media, were used. A distinct concentration related activity was seen for most of the compounds. The molar activity of the caffeoyl esters against the bacteria was similar to that of tartaric acid, higher than that of phenol, but much lower than that of streptomycin. For most host plants, their ‘own’ compounds were less active against their pathogens than foreign ones. Of the tested compounds, ferulic acid, caffeic acid, esculine, esculetin and orobanchoside were the most active against the two fungi, and similarly, ferulic acid and esculetin were the most active against the bacteria.

In this review, the distribution of phenylpropanoic acids in dicotyledons is visualized by using the Dahlgren diagram. Notably derivatives of caffeic acid show a close correlation with the taxonomic arrangement of plant families and orders. Generally, the hydroxycinnamic acids are ester bound to various alcohols, most frequently sugars, giving mono-, di- and trisaccharide esters. The monosaccharide esters are fairly common in all dicotyledons, whereas di- and trisaccharide esters occur exclusively in sympetalous orders. In these orders, rosmarinic acid and quinic acid esters, i.e. chlorogenic acid, have an alternative distribution to that of the disaccharide esters. Hence, chlorogenic acid is common in Asteraceae, Solanaceae and Rubiaceae, whereas rosmarinic acid and related compounds are restricted to Lamiaceae and Boraginaceae, and the disaccharide esters mainly to Scrophulariaceae and Oleaceae. Of more restricted occurrence are ferulic acid in Caryophyllales and derivatives with sinapic acid in Brassicaceae. The distribution is discussed in relation to the supposed evolution of chemical structures by derivation of intermediates in the biosynthetic route. Hence, the most derived compounds are found in the most remote groups of the Lamianae, e.g. Orobanchaceae.