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Emmentaler is a hard cheese produced and consumed in many countries. The authenticity of this cheese variety is becoming a matter of national importance with the imminent opening of the cheese market in Switzerland and the introduction of the PDO label for the Emmentaler Switzerland™. This paper is the first in a series reporting the search for parameters that make possible a geographic discrimination of Emmentalers. Twenty Emmentaler cheese samples from six regions in Europe (one from Switzerland, two from France, one from Austria, one from Germany and one from Finland) were considered. In this paper, chemical, biochemical, microbiological, colour and sensory parameters were investigated leading to the following preliminary results. The presence of Lb. helveticus seemed to be a good indicator of an origin other than Swiss. The concentration of enterococci, facultative and obligate heterofermentative lactobacilli and salt tolerant bacteria was significantly lower in Emmentaler Switzerland™ than in the foreign cheeses. Chemical parameters such as fat content and pH value as well as biochemical parameters such as L- and D-lactate and pyruvate allowed us to partially discriminate between the regions when these data were combined by principal component analysis. The colour of the body also showed significant differences.

• The internal concentration of isoflavonoids in white lupin (Lupinus albus) cluster roots and the exudation of isoflavonoids by these roots were investigated with respect to the effects of phosphorus (P) supply, root type and cluster-root developmental stage. • To identify and quantify the major isoflavonoids exuded by white lupin roots, we used high-pressure liquid chromatography (HPLC) coupled to electrospray ionization (ESI) in mass spectrometry (MS). • The major exuded isoflavonoids were identified as genistein and hydroxygenistein and their corresponding mono- and diglucoside conjugates. Exudation of isoflavonoids during the incubation period used was higher in P-deficient than in P-sufficient plants and higher in cluster roots than in noncluster roots. The peak of exudation occurred in juvenile and immature cluster roots, while exudation decreased in mature cluster roots. • Cluster-root exudation activity was characterized by a burst of isoflavonoids at the stage preceding the peak of organic acid exudation. The potential involvement of ATP-citrate lyase in controlling citrate and isoflavonoid exudation is discussed, as well as the possible impact of phenolics in repelling rhizosphere microbial citrate consumers.

Within the framework of the European COST Action 816, afive-year collaboration between scientists from five Europeancountries has made an important contribution to biologicalcontrol of field and hedge bindweeds (Convolvulus arvensis and Calystegia sepium, respectively). A fungus Stagonosporaconvolvuli strain LA39, able to infect both field and hedgebindweed, was found in the UK and its biocontrol efficacyimproved by optimising mass production, formulation and storagetechniques. This fungus controlled bindweeds in both a cemeteryand in maize crops. Its use fits best in an integrated pestmanagement system where a green cover controls most of the weedsexcept the bindweeds. DNA marker analyses indicate that thefungus reproduces sexually, which could be used to furtherimprove this mycoherbicide. In addition, the insect Melanagromyzaalbocilia, which itself exhibits biocontrol potential againstbindweeds, may be used in combination with LA39 to improve theability of the fungus to penetrate the stem of bindweeds.Overall, the results suggest that S. convolvuli LA39 haspromising potential as a bioherbicide for control of field andhedge bindweed.

Electronic noses produce data which are difficult to transfer between identical instruments because of differences in the characteristics of "identical" instruments and because of sensor drift. The transportability of data is, however, essential for the setting up of databanks. Results of the present investigation, using processed cheeses and evaporated milk as reference materials, show that data transfer between two electronic noses based on mass spectrometry is possible and simple.

A short and efficient protocol for the asymmetric synthesis of cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-one (1 and 2, resp.) is described, with a phthalide annulation as the key step. Introduction of a OH substituent at position 2 was performed by Sharpless dihydroxylation of a silyl enol ether or by means of an N-sulfonyloxaziridine. The absolute configuration of each isomer was determined via Mosher-ester derivatives. By comparison with previously recorded CD spectra of our natural sample, we established that the natural trans- and cis-isomers from Ceratocystis fimbriata sp. platani were the (-)-(2S,4S)-isomer (-)-2 and the (+)-(2S,4R)-isomer (+)-1, respectively.

White lupins (Lupinus albus L.) respond to phosphate deficiency by producing special root structures called cluster roots. These cluster roots secrete large amounts of carboxylates into the rhizosphere, mostly citrate and malate, which act as phosphate solubilizers and enable the plant to grow in soils with sparingly available phosphate. The success and efficiency of such a P-acquisition strategy strongly depends on the persistence and stability of the carboxylates in the soil, a parameter that is influenced to a large extent by biodegradation through rhizosphere bacteria and fungi. In this study, we show that white lupin roots use several mechanisms to reduce microbial growth. The abundance of bacteria associated with cluster roots was decreased at the mature state of the cluster roots, where a burst of organic acid excretion and a drastic pH decrease is observed. Excretion of phenolic compounds, mainly isoflavonoids, induced fungal sporulation, indicating that vegetative growth, and thus potential citrate consumption, is reduced. In addition, the activity of two antifungal cell wall-degrading enzymes, chitinase and glucanase, were highest at the stage preceding the citrate excretion. Therefore, our results suggest that white lupin has developed a complex strategy to reduce microbial degradation of the phosphate-solubilizing agents.

The goal of this work was to classify European Emmental cheeses according to their geographic origin using analytical approaches. Twenty-five analytical parameters (factors) were measured in 183 samples. Results were combined by multivariate statistical analysis. Discriminant analysis (DA) and an artificial neural network (ANN) delivered similar results when all regions and factors were included; 95% and 91%, respectively, of the samples were correctly classified in the validation procedure. To reduce the analytical costs and the risk of overfitting, a DA based on a selection of only 11 factors was calculated. In this case, the Jackknifed validation delivered 95% correct assignments. Finally, a system was optimised to discriminate between the Swiss samples and cheeses from other regions. Building a new model for each of the six pairs, Switzerland vs. another region, 100% correct classification could be achieved for the Swiss samples.

A comprehensive review is presented on extracts of a lichen, oakmoss (Evernia prunastri), that are used in the fragrance industry. Analytical aspects are discussed in detail, from both qualitative and quantitative standpoints, mainly in relation to the industrial processing of the lichen. It is shown that more than 170 constituents have been identified so far in oakmoss extracts, including 47 depsides or depside-derived compounds and 25 triterpenes or steroids. A survey of industrially relevant synthetic products with an oakmoss odour is included. Toxicology issues related to the use of oakmoss extracts in cosmetics and fragrance formulations are critically reviewed.

This is a comprehensive review of extracts from the lichen Pseudevernia furfuracea (treemoss) that are used in the fragrance industry. Qualitative and quantitative analytical aspects are critically reviewed and the results are compared to those of the related oakmoss extracts. It is shown that more than 90 constituents have been identified so far in treemoss extracts, including 42 depsides, depsidones or depside-derived compounds, and 42 triterpenes or steroids. Constituents of certain host trees, mainly Pinus species, generate specific analytical and toxicological issues which need to be considered in addition to those related to the known degradation products of lichen compounds. A new classification of lichen extracts used as raw materials in fragrance compounding is proposed.

Two clerodane diterpenoids, Bafoudiosbulbins A 1, and B 2, together with five known compounds: tetracosanoic acid, 1-(tetracosanoyl)-glycerol, trans-tetracosanylferulate, β-sitosterol and 3-O-β-d-glucopyranosyl-β-sitosterol were isolated from the tubers of Dioscorea bulbifera L. var sativa. Their structures were established by spectroscopic methods (1D and 2D-NMR, MS) and X-ray crystallographic diffraction analysis of compound 1. The CH2Cl2-soluble portion of the crude extract and the two clerodanes were screened for anti-bacterial activity using both agar diffusion and broth dilution techniques against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella typhi, Salmonella paratyphi A and Salmonella paratyphi B. They both showed significant activities against P. aeruginosa, S. typhi, S. paratyphi A and S. paratyphi B.

Columns containing different types of cyclodextrin derivatives have been evaluated for chiral gas chromatographic separation of atropisomeric PCBs, o,p´-DDT and o,p´-DDD. Separation was attempted on columns containing mixed chiral selectors, and the performance of two closely related selectors was also examined. The cyclodextrins were: permethylated- β -CD (PM- β -CD), heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-β-CD (2,3-M-6-TBDMS- β -CD), heptakis(2,3-di-O-methyl-6-O-tert-hexyldimethylsilyl)- β -CD (2,3-M-6-THDMS- β -CD), and heptakis(2,3-di-O-ethyl-6-O-tert-hexyldimethylsilyl)- β -cyclodextrin (2,3-E-6-THDMS- β -CD). The cyclodextrins were dissolved in OV-1701 or in a dimethylsiloxane/silarylene copolymer containing 5% phenyl in the backbone. The application of mixed chiral selectors led to improved separations, however; at most eleven PCB congeners were separated on a single column. Chiral resolution of o,p´-DDD was achieved. The use of a dimethylsiloxane/silarylene copolymer as a matrix for the cyclodextrins is a promising approach. With such a matrix, blocking of the CD cavities by silicone substituent groups can be avoided, and a reasonable CD solubility can be provided. The selectivity of heptakis(2,3-di-O-ethyl-6-O-tert-hexyldimethylsilyl)- β -CD and heptakis(2,3-di-O-methyl-6-O-tert-hexyldimethylsilyl)- β -CD was quite different, the former selector could separate four congeners, while the latter separated ten congeners.

To survey the authenticity of Emmental cheese from some of the main European countries of origin, samples of cheeses manufactured during winter (110 samples) and summer (73 samples) were collected. From a preliminary study, a series of promising analytical methods were selected and applied: total nitrogen, water soluble nitrogen (WSN), 12% TCA soluble nitrogen (TCA-SN), pH-value, volatile short-chain acids, chloride, organic acids, enterococci, obligate heterofermentative lactobacilli (OHL), Lactobacillus helveticus, sodium, copper, zinc, magnesium and stable isotope ratios (δ2H, δ13C, δ15N, δ34S). The data were analysed by univariate statistical methods according to the geographic origin and the season of production. Significant differences between the regions of origin were found for all parameters investigated (P≤0.001). Cheeses from some regions showed very specific properties. Seasonal differences were observed in certain regions for acetate, propionate, caproate, WSN, TCA-SN, pyruvate, OHL, zinc and δ13C levels.

Within the framework of the European COST Action 816, afive-year collaboration between scientists from five Europeancountries has made an important contribution to biologicalcontrol of field and hedge bindweeds (Convolvulus arvensis and Calystegia sepium, respectively). A fungus Stagonosporaconvolvuli strain LA39, able to infect both field and hedgebindweed, was found in the UK and its biocontrol efficacyimproved by optimising mass production, formulation and storagetechniques. This fungus controlled bindweeds in both a cemeteryand in maize crops. Its use fits best in an integrated pestmanagement system where a green cover controls most of the weedsexcept the bindweeds. DNA marker analyses indicate that thefungus reproduces sexually, which could be used to furtherimprove this mycoherbicide. In addition, the insect Melanagromyzaalbocilia, which itself exhibits biocontrol potential againstbindweeds, may be used in combination with LA39 to improve theability of the fungus to penetrate the stem of bindweeds.Overall, the results suggest that S. convolvuli LA39 haspromising potential as a bioherbicide for control of field andhedge bindweed.

The regioselective synthesis of two new acetylenic compounds, sterehirsutinal (1) and sterehirsutinol (2), isolated recently from culture medium of the fungus Stereum hirsutum, is reported.

White lupins (Lupinus albus L.) respond to phosphate deficiency by producing special root structures called cluster roots. These cluster roots secrete large amounts of carboxylates into the rhizosphere, mostly citrate and malate, which act as phosphate solubilizers and enable the plant to grow in soils with sparingly available phosphate. The success and efficiency of such a P-acquisition strategy strongly depends on the persistence and stability of the carboxylates in the soil, a parameter that is influenced to a large extent by biodegradation through rhizosphere bacteria and fungi. In this study, we show that white lupin roots use several mechanisms to reduce microbial growth. The abundance of bacteria associated with cluster roots was decreased at the mature state of the cluster roots, where a burst of organic acid excretion and a drastic pH decrease is observed. Excretion of phenolic compounds, mainly isoflavonoids, induced fungal sporulation, indicating that vegetative growth, and thus potential citrate consumption, is reduced. In addition, the activity of two antifungal cell wall-degrading enzymes, chitinase and glucanase, were highest at the stage preceding the citrate excretion. Therefore, our results suggest that white lupin has developed a complex strategy to reduce microbial degradation of the phosphate-solubilizing agents.

A short and efficient protocol for the asymmetric synthesis of cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-one (1 and 2, resp.) is described, with a phthalide annulation as the key step. Introduction of a OH substituent at position 2 was performed by Sharpless dihydroxylation of a silyl enol ether or by means of an N-sulfonyloxaziridine. The absolute configuration of each isomer was determined via Mosher-ester derivatives. By comparison with previously recorded CD spectra of our natural sample, we established that the natural trans- and cis-isomers from Ceratocystis fimbriata sp. platani were the (-)-(2S,4S)-isomer (-)-2 and the (+)-(2S,4R)-isomer (+)-1, respectively.

Emmentaler is a hard cheese produced and consumed in many countries. The authenticity of this cheese variety is becoming a matter of national importance with the imminent opening of the cheese market in Switzerland and the introduction of the PDO label for the Emmentaler Switzerland™. This paper is the first in a series reporting the search for parameters that make possible a geographic discrimination of Emmentalers. Twenty Emmentaler cheese samples from six regions in Europe (one from Switzerland, two from France, one from Austria, one from Germany and one from Finland) were considered. In this paper, chemical, biochemical, microbiological, colour and sensory parameters were investigated leading to the following preliminary results. The presence of Lb. helveticus seemed to be a good indicator of an origin other than Swiss. The concentration of enterococci, facultative and obligate heterofermentative lactobacilli and salt tolerant bacteria was significantly lower in Emmentaler Switzerland™ than in the foreign cheeses. Chemical parameters such as fat content and pH value as well as biochemical parameters such as L- and D-lactate and pyruvate allowed us to partially discriminate between the regions when these data were combined by principal component analysis. The colour of the body also showed significant differences.

Electronic noses produce data which are difficult to transfer between identical instruments because of differences in the characteristics of "identical" instruments and because of sensor drift. The transportability of data is, however, essential for the setting up of databanks. Results of the present investigation, using processed cheeses and evaporated milk as reference materials, show that data transfer between two electronic noses based on mass spectrometry is possible and simple.

• The internal concentration of isoflavonoids in white lupin (Lupinus albus) cluster roots and the exudation of isoflavonoids by these roots were investigated with respect to the effects of phosphorus (P) supply, root type and cluster-root developmental stage. • To identify and quantify the major isoflavonoids exuded by white lupin roots, we used high-pressure liquid chromatography (HPLC) coupled to electrospray ionization (ESI) in mass spectrometry (MS). • The major exuded isoflavonoids were identified as genistein and hydroxygenistein and their corresponding mono- and diglucoside conjugates. Exudation of isoflavonoids during the incubation period used was higher in P-deficient than in P-sufficient plants and higher in cluster roots than in noncluster roots. The peak of exudation occurred in juvenile and immature cluster roots, while exudation decreased in mature cluster roots. • Cluster-root exudation activity was characterized by a burst of isoflavonoids at the stage preceding the peak of organic acid exudation. The potential involvement of ATP-citrate lyase in controlling citrate and isoflavonoid exudation is discussed, as well as the possible impact of phenolics in repelling rhizosphere microbial citrate consumers.

This is a comprehensive review of extracts from the lichen Pseudevernia furfuracea (treemoss) that are used in the fragrance industry. Qualitative and quantitative analytical aspects are critically reviewed and the results are compared to those of the related oakmoss extracts. It is shown that more than 90 constituents have been identified so far in treemoss extracts, including 42 depsides, depsidones or depside-derived compounds, and 42 triterpenes or steroids. Constituents of certain host trees, mainly Pinus species, generate specific analytical and toxicological issues which need to be considered in addition to those related to the known degradation products of lichen compounds. A new classification of lichen extracts used as raw materials in fragrance compounding is proposed.

A short and efficient protocol for the stereoselective synthesis of racemic trans- and cis-3,4-dihydro-3,4,8-trihydroxynaphthalen-1(2H)-one (1 and 2, resp.), is described, comprising nine and eight steps starting from commercial juglone (=5-hydroxynaphthalene-1,4-dione; 12) (Scheme 4). Furthermore, an attempt to obtain 1 and 2 via phthalide annulation as the key step (Schemes 2 and 3) and a regioselective oxidation of the intermediate 1,2,3,4-tetrahydronaphthalene-1,2,4,5-tetrols 27 and 28 with activated MnO2 were carried out (Scheme 4).

A comprehensive review is presented on extracts of a lichen, oakmoss (Evernia prunastri), that are used in the fragrance industry. Analytical aspects are discussed in detail, from both qualitative and quantitative standpoints, mainly in relation to the industrial processing of the lichen. It is shown that more than 170 constituents have been identified so far in oakmoss extracts, including 47 depsides or depside-derived compounds and 25 triterpenes or steroids. A survey of industrially relevant synthetic products with an oakmoss odour is included. Toxicology issues related to the use of oakmoss extracts in cosmetics and fragrance formulations are critically reviewed.

The goal of this work was to classify European Emmental cheeses according to their geographic origin using analytical approaches. Twenty-five analytical parameters (factors) were measured in 183 samples. Results were combined by multivariate statistical analysis. Discriminant analysis (DA) and an artificial neural network (ANN) delivered similar results when all regions and factors were included; 95% and 91%, respectively, of the samples were correctly classified in the validation procedure. To reduce the analytical costs and the risk of overfitting, a DA based on a selection of only 11 factors was calculated. In this case, the Jackknifed validation delivered 95% correct assignments. Finally, a system was optimised to discriminate between the Swiss samples and cheeses from other regions. Building a new model for each of the six pairs, Switzerland vs. another region, 100% correct classification could be achieved for the Swiss samples.