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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.

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.

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.

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.