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Pure and natural essential oils of Allium species are primarily used in the food industry, but due to their low yield, production quantities can be difficult to achieve and thus can be highly expensive. Due to these problems, adulterations are a reality in this field. The purpose of this research is to develop a multi element stable isotope analysis methodology for authentication of the essential oils of leek, onion, shallot, and chive. Naturalness of these essential oils was achieved by assessment of compound specific δ13C and δ34S: an addition of 5% of synthetic compound can be detected. Chemometric models were undertaken to assess purity by distinction of the Allium samples according to their species origin using bulk stable and compound specific δ13C, δ2H, δ34S, and compositions of their major metabolites dipropyl disulfide, dipropyl trisulfide, methyl propyl disulfide, and methyl propyl trisulfide.

In this work, impedimetric sensors were developed for the detection of the four WFD heavy metals Pb2+, Cd2+, Hg2+ and Ni2+, by the modification of a gold electrode with four partially biosourced polyphosphine polymers. These polymers were obtained with satisfactory yields by polycondensation of the bis(4-fluorophenyl)(4-methylphenyl)phosphine sulfide and the bis(4-fluorophenyl)(4-methylphenyl)phosphine oxide using isosorbide or bisphenol A. The chemical structures and number-average molecular weights of the resulting polymers were determined by NMR spectroscopy (1H, 19F, and 31P) and by size exclusion chromatography. Glass transition temperatures varied between 184 and 202 &deg, C depending on the composition of polymers. The bio-based poly(etherphosphine) oxide modified sensor showed better analytical performance than petrochemical based oxide for the detection of Pb2+. A detection limit of 10&minus, 10 g/L or 0.5 pM, which is 104 times lower than that of the anodic stripping voltammetric and the potentiometric sensors. A reversibility is obtained through rinsing of the impedimetric sensor with an EDTA solution.

Neroli essential oil (EO), extracted from bitter orange blossoms, is one of the most expensive natural products on the market due to its poor yield and its use in fragrance compositions, such as cologne. Multiple adulterations of neroli EO are found on the market, and several authentication strategies, such as enantioselective gas chromatography (GC) and isotope ratio mass spectrometry (IRMS), have been developed in the last few years. However, neroli EO adulteration is becoming increasingly sophisticated, and analytical improvements are needed to increase precision. Enantiomeric and compound-specific isotopic profiling of numerous metabolites using multidimensional GC and GC-C/P-IRMS was carried out. These analyses proved to be efficient for geographical tracing, especially to distinguish neroli EO of Egyptian origin. In addition, δ2H values and enantioselective ratios can identify an addition of 10% of petitgrain EO. These results demonstrate that enantioselective and stable isotopic metabolite fingerprint determination is currently a necessity to control EOs.

Changes in fatty acid profile, lipid quality, essential oil composition, total phenolic (TPC) and flavonoid (TFC) contents, radical scavenging, antibacterial and insecticidal activities were studied during the maturation of Schinus terebinthifolius Raddi fruits. Total lipids showed their maximum at the earlier and intermediate stage (green and half-red) of maturation, whereas, the highest levels of the main components linoleic and oleic acids were found at the late stage (red). Mature fruits were also distinguished by their high lipid quality as revealed by the lower values of n-3/n-6 ratio, calculated oxidizability (Cox), oxidative susceptibility (OS), atherogenic index (AI) and thromobogenic index (TI). The contents of monoterpenes decreased while those of sesquiterpenes increased during maturation. With the exception of α-pinene which dropped remarkably from immature to mature fruits, the content of the other main components (α-phellandrene, β-phellandrene and limonene) showed irregular variations. The TPC in intact and hydrodistilled fruits was higher at the last stage of maturation, while the maximum of TFC was recorded in the intermediate stage. Concomitantly, extract from residual hydrodistilled fruits was found as the most potent radical scavengers, whereas, the oils were found as the least scavengers. Nevertheless, they showed an appreciable antibacterial activity against Enterococcus feacium and Streptococcus agalactiae and exert a strong insecticidal activity against Spodoptera littoralis and Phthorimaea operculella . Collectively, these results suggest that the fruits of S. terebinthifolius could be considered as consolidated source of lipid and essential fatty acids, which may provide some health benefits to consumers. They also showed that the essential oils of S. terebinthifolius fruits can potentially be used in S. littoralis and P. operculella control in association with integrated pest management practices. Moreover, the use of extracts from intact or hydrodistilled residual fruits for the development of functional ingredients and the production of bio-based preservatives is encouraged.

In a stricter legislative context, greener detergent formulations are developed. In this way, synthetic surfactants are frequently replaced by bio-sourced surfactants and/or used at lower concentrations in combination with enzymes. In this paper, a LC-MS/MS method was developed for the identification and quantification of enzymes in laundry detergents. Prior to the LC-MS/MS analyses, a specific sample preparation protocol was developed due to matrix complexity (high surfactant percentages). Then for each enzyme family mainly used in detergent formulations (protease, amylase, cellulase, and lipase), specific peptides were identified on a high resolution platform. A LC-MS/MS method was then developed in selected reaction monitoring (SRM) MS mode for the light and corresponding heavy peptides. The method was linear on the peptide concentration ranges 25-1000 ng/mL for protease, lipase, and cellulase; 50-1000 ng/mL for amylase; and 5-1000 ng/mL for cellulase in both water and laundry detergent matrices. The application of the developed analytical strategy to real commercial laundry detergents enabled enzyme identification and absolute quantification. For the first time, identification and absolute quantification of enzymes in laundry detergent was realized by LC-MS/MS in a single run. Graphical Abstract Identification and quantification of enzymes by LC-MS/MS.

RATIONALE To develop more eco-friendly laundry detergents, renewable surfactants synthesized from vegetal sources are increasingly being used. In a more stringent regulation context, the determination of bio-sourced surfactant origin thus appears essential to assess the claims of detergent manufacturers. Radiocarbon determination, the standard method for the analysis of bio-sourced materials, is an expensive technique, so there is a need for a cheaper method. METHODS Here, the use of an elemental analyzer linked to isotope-ratio mass spectrometry (EA/IRMS) is evaluated as an alternative approach to the official method. The δ(18) O, δ(13) C and δ(2) H isotope-ratio values were determined to investigate the bio-sourced origin of surfactant raw materials and mixtures. RESULTS A sample library of 26 commercial surfactants representative of detergent raw materials was first analyzed by EA/IRMS. The δ(18) O, δ(13) C and δ(2) H values allowed discrimination of synthetic and bio-sourced surfactants. Moreover, in this latter group, C4 plant-derived surfactants were distinguished by their δ(13) C values. Binary and ternary mixtures made of synthetic and bio-sourced surfactants were also analyzed and indicated a linear relationship between mixture isotope-ratio values and surfactant proportions. CONCLUSIONS IRMS represents a viable alternative to radiocarbon determination for the evaluation of surfactant bio-sourced origin. It is a faster and cheaper technique, allowing discrimination of petroleum- and biomass-derived surfactants and identification of their carbon sources (C4 or C3 plants).

International audience; The fatty acid, essential oil compositions and their respective antioxidant and antibacterial activities was determined in Schinus terebinthifolius Raddi leaves and twigs. The lipid content ranged from 1.75 to 4.65% in twigs and leaves, respectively. Thirteen fatty acids were identified with α-linolenic (C18:3), palmitic (C16:0) and linoleic (C18:2) acids being the main components. The essential oils of both organs were characterized by a high amount of monoterpene hydrocarbons (68.91-74.88%) with α-phellandrene (33.06-36.18%), α-pinene (14.85-15.18%) and limonene (6.62-8.79%) being the chief components. The DPPH˙ radical scavenging assay revealed that both oils have a very weak antiradical activity. In contrast, they showed an appreciable antibacterial activity against the gram-positive Enterococcus feacium (ATCC 19434) and Streptococcus agalactiae (ATCC 13813) bacteria. These results suggest that leaves and twigs of S. terebinthifolius could be considered as an important dietary source of health promoting phytochemicals and has a good potential for use in food industry and pharmacy.

International audience; The present work aims to investigate the maturation-related changes in phenolic profile of Melia azedarach (L.) leaves (young and old) and fruits (pulp and kernel) at two developmental stages. A total of 26 phenolic compounds were identified by high-performance liquid chromatography-diode-array detector-hyphenated with tandem mass spectromdtry (HPLC-DAD-ESI MS/MS). They include phenolic acids, flavonols and flavanols which were found mostly in glycosylated forms. The main phenolic compounds were found to be rutin (5.86-21.33%, of total integrated peak area at 280 nm), quercetin-3-O-neohesperidoside (3.95-8.76%), kaempferol-3-O-rutinoside (2.73-11.23%), feruloylglucaric acid (0.85-11.84%) and feruloylquinic acid derivative (1.94-11.07%). The pattern distribution of phenolic compounds was organ-specific, and somewhat variable depending on the stage of maturation. Additionally, the total phenol content was determined as well as the antioxidant capacity using different in vitro assays. The extracts of young leaves demonstrated the highest total phenol content (85.4 mg GAE/g extract), and exhibited the strongest scavenging activity against 2,2-diphenyl-1-picrylhydrazyl DPPH and the highest oxygen radical absorbance capacity ORAC (235 and 328 mg Trolox equivalents/g extract, respectively) compared to old leaves and immature/mature fruit parts. In contrast, the highest metal chelating activity (MCA) was observed in immature pulp extracts (22.85 mg EDTA equivalents/g extract). Pearson's correlation and principal component analysis (PCA) showed that quercetin-3-O-neohesperidoside, rutin and kaempferol-3-O-rutinoside were the main contributors on the antioxidant capacity. On the basis of these results, M. azedarach could serve as an excellent source of natural antioxidants which could be used for pharmaceutical and cosmeceutical applications.

Purpose The paper aims to analyse the effect of acid hydrolysis on the chemical composition and the biological activities of Rubia tinctorum collected from the south of Tunisia. It proposes to clarify the relationship between alizarin content and the antioxidant and antimicrobial activities of Rubia extract. Design/methodology/approach The paper opted for analytical tools (HPLC) and the in-vitro study of biological activities, namely, the antioxidant activity which is evaluated using the radical scavenging assay (ABTS) and ferric reducing power assay (FRAP); the antimicrobial activity is tested using the wells agar diffusion method. Findings The paper provides information about the positive effect of acid hydrolysis, namely, the enhancement of alizarin content in the extract which has increased its antioxidant and antimicrobial activities. Originality/value This paper fulfils an identified need to study the relationship between the chemical composition, biological activities and colour enhancement.

International audience; Volatile oil constituents of Tunisian sweet orange (Citrus sinensis Osbeck) cv. Meski (MES), Valencia Late (VAL), Thomson Navel (THN) and Maltaise Blanc (MAB); mandarin (Citrus reticulate Blanco); sour orange (Citrus aurantium L cv. Amara (AM)) and pummelo (Citrus grandis Osbeck) were obtained by hydrodistillation and analysed by gas chromatography (GC) combined with a flame ionisation detector (FID) and mass spectrometry (MS). A total of 41 components accounting for more than 95% of the total essential oils were identified, and oxygenated monoterpenes (69.5-99.9%) were found as the most prominent fraction in all oil samples. The main constituents were linalool (3.1-73%), isoborneol (0-55.8%) and tepinen-4-ol (1.1-19.2%). A high degree of inter-and intraspecific chemical variability between species and cultivars was found to be genetically determined, and a set of distinctive traits (chemical markers) in the essential oils profile was established. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) of all identified components grouped the oils into two main chemotypes (linalool/isoborneol and isoborneol/linalool).

International audience; A comprehensive study on the volatile oil and phenolic constituents of Ailanthus altissima Swingle (Simaroubaceae) leaves was performed. Methanolic extracts of leaves and their hydrodistilled residues were screened for their antioxidant, antimicrobial and phytotoxic properties. The results showed that the leaf volatile oils were a complex mixture of more than a hundred components, mainly composed by non-terpenic compounds (tetradecanol, heneicosane, tricosane and docosane) and sesquiterpene hydrocarbons (α-curcumene and α-gurjunene). Methanolic extracts from leaves contain the highest level of total phenolic content, while those from the hydrodistilled residues showed the highest total flavonoid content. The most frequent phenolic compounds identified by HPLC-DAD-MS were gallic acid, chlorogenic acid, HHDP-galloylglucose, epicatechin, rutin, hyperoside and quercetin-3-galloyl hexoside. Evaluation of the antioxidant activities by using four complementary tests (DPPH, ABTS, 2-deoxyribose and FRAP) showed that both extracts exhibited strong concentration-dependent antioxidant activities. These extracts were efficient against Gram-positive bacteria, but not active against Gram-negative bacterial strains and the yeast Candida albicans. They also exhibited strong inhibitory effects on the germination and the radicle growth of the wild Daucus carota. This work provides scientific supports for the high antioxidant and phytotoxic activities of this species and thus, it may find potential applications in the development of natural herbicides and antioxidants for agro-food and pharmaceutical industries.

International audience; A reliable database is established from the analysis of 500 French royal jellies (RJ). Diversity of geographical origins, harvesting seasons, and forage sources were taken into account. Authenticity intervals for numerous physicochemical parameters have been established from French RJs, obtained without bee-feeding with artificial sugars or proteins. RJs from Italy and non-European countries, derived from feeding experiments, were analysed and compared with the database. Differences in 10-HDA, d13C and sugars (sucrose, erlose, maltose, maltotriose) contents were observed. Sucrose and erlose contents in French RJs were less than 1.8 and 0.4%, respectively, whereas they attained 3.9 and 2.0% in some commercial samples and 7.7 and 1.7% in RJs produced by sugarcane feeding. Maltose and maltotriose contents were less than 1.0 and 0.2% in French RJs, and they can attain levels of 2.6 and 0.4% in commercial samples; they can be as high as 5.5 and 1.7% in RJs obtained by bee-feeding with starch hydrolysate syrups. RJs obtained with and without feeding exhibit d13C values ranging from 26.45 to 23.73%, and from 26.05 to 14.65%, respectively. This study could be used to discriminate different production methods and provide a useful tool for identifying unknown commercial RJs. Highlights A total of 750 royal jellies (RJs) from different origins were studied. Origins included domestic, imported, obtained by bee-feeding. French RJ samples were chemically characterised. Authenticity intervals were calculated for authentic RJs. Sucrose, erlose, maltose, maltotriose and δ13C contents are bee-feeding markers.

International audience; The present work constitutes a contribution to the phytochemical investigation of Hedysarum carnosum aiming to search for novel bioactives secondary metabolites. In this context, the fractionation of the butanolic extract of H. carnosum flowers afforded two new flavonoid glycosides quercetin 3-O-beta-D-glucopyranosyl-(1 -> 2)-alpha-L-rhamnopyranosyl-(1 -> 6)-alpha-L-rhamnopyranoside 1 and kaempferol 3-O-beta-D-glucopyranosyl-(1 -> 2)-alpha-L-rhamnopyranosyl-(1 -> 6)-alpha-L-rhamnopyranoside 2 together with a the known rutin 3 indicated for the first time in this species. Their structures were determined on the basis of spectroscopic evidences (UV, HRMS and NMR) and comparison with literature. The fatty acid composition of the hexane extract of this species was also investigated by using GC-MS. The n-butanol extract and the isolates were assessed for their antioxidant potential using DPPH center dot and ABTS(center dot+) scavenging assays and ferric reducing power (FRAP). The n-butanol extract and its fractions exhibited efficient radical scavenging activity with IC50 values ranging from 16 to 37 mu g/mL for the DPPH center dot assay. The obtained results suggest that the isolated compounds 1 and 3 could be promising antioxidant agents.

RATIONALE The analytical composition and botanical origin of honey are basic data used to determine the quality of this foodstuff. Although proteins are used to characterise the analytical composition of honey, they can be eliminated during its ultrafiltration and, in the case of honeys not saturated with their own pollen, the use of proteins does not work well. As acidity is a well-known characteristic of honey and organic acids are present at around 0.5% in honey, we therefore investigated an alternative method to the protein-based White method, using organic acids as new internal standards instead of proteins. METHODS The qualitative and quantitative analyses of 14 organic acids were carried out by ion chromatography with an electrochemical detector. The 13C/12C isotopic ratios of the honeys, and of the organic acids extracted from them with an anion exchange resin, were determined by isotope ratio mass spectrometry. RESULTS Gluconic acid is the predominant organic acid in honey, at between 1.8 and 12.7 g/kg. For fir honey the major acid is galacturonic acid at around 4.6 g/kg. The isotopic ratios of honeys and of their acids are strongly linked. Correlations between the δ13C values of the honey and the acids were significant, and better than those obtained using proteins. CONCLUSIONS This study has provided a method to differentiate honeys from seven botanical origins, based on organic acid analysis. By combining various organic acid contents and isotopic ratio values through statistical processing by Principal Component Analysis it is possible to differentiate honey samples as a function of their botanical origin. Copyright © 2012 John Wiley & Sons, Ltd.

International audience; The effects of feeding bees artificial sugars and/or proteins on the sugar compositions and (13)C isotopic measurements of royal jellies (RJs) were evaluated. The sugars fed to the bees were two C4 sugars (cane sugar and maize hydrolysate), two C3 sugars (sugar beet, cereal starch hydrolysate), and honey. The proteins fed to them were pollen, soybean, and yeast powder proteins. To evaluate the influence of the sugar and/or protein feeding over time, samples were collected during six consecutive harvests. (13)C isotopic ratio measurements of natural RJs gave values of around -25 ‰, which were also seen for RJs obtained when the bees were fed honey or C3 sugars. However, the RJs obtained when the bees were fed cane sugar or corn hydrolysate (regardless of whether they were also fed proteins) gave values of up to -17 ‰. Sugar content analysis revealed that the composition of maltose, maltotriose, sucrose, and erlose varied significantly over time in accordance with the composition of the syrup fed to the bees. When corn and cereal starch hydrolysates were fed to the bees, the maltose and maltotriose contents of the RJs increased up to 5.0 and 1.3 %, respectively, compared to the levels seen in authentic samples (i.e., samples obtained when the bees were fed natural food: honey and pollen) that were inferior to 0.2% and not detected, respectively. The sucrose and erlose contents of natural RJs were around 0.2 %, whereas those in RJs obtained when the bees were fed cane or beet sugar were as much as 4.0 and 1.3 %, respectively. The combination of sugar analysis and (13)C isotopic ratio measurements represents a very efficient analytical methodology for detecting (from early harvests onward) the use of C4 and C3 artificial sugars in the production of RJ.

International audience; The effect of stage of maturity on total lipids, fatty acids, yields and essential oil composition and their antimicrobial and free radical scavenging activities of the Schinus molle fruits was investigated. The content of total lipids varied from 2.87 to 5.35% (w/w, dw) and were rich in unsaturated fatty acids particularly linoleic acid. As maturation progress, the essential oil yield dropped from 5.18% to 1.15%. Monoterpene hydrocarbons with α-phellandrene (35.15-40.38%), limonene + β-phellandrene (21.47-36.62%), β-myrcene (7.61-24.96%) and α-pinene (1.92-2.58%) were found to be the main components. At the same time, the essential oils were evaluated for their antimicrobial and free radical scavenging activities. They were found to be active against Bacillus subtilis, Bacillus cereus, Salmonella typhymurium and Escherichia coli but they do not inhibit the growth of Candida albicans. Conversely, they showed very weak activity against the DPPH radical. In both assay, the oil derived from the intermediate stage was reported as more efficient.

The carbon and nitrogen stable ratios of royal jelly (RJ) samples from various origins are determined using an elemental analyser linked online to an isotope ratio mass spectrometer to evaluate authenticity and adulteration. The (13)C/(12)C and (15)N/(14)N stable isotope ratios are measured in more than 500 RJs (domestic, imported and derived from feeding experiments) in order to obtain isotopic measurements that take into account seasonal, botanical and geographical effects. Authenticity intervals are established for traditional beekeeping practices, without feeding, in the range -22.48 to -27.90‰ for δ(13)C. For these samples, the δ(15)N values range from -1.58 to 7.98‰, depending on the plant sources of pollen and nectar. The δ(13)C values of the commercial samples vary from -18.54 to -26.58‰. High δ(13)C values are typical of sugar cane or corn syrups which have distinctive isotopic (13)C signatures because both plants use the C4 photosynthetic cycle, in contrast to most RJs which are derived from C3 plants. These differences in the (13)C-isotopic composition allow the detection of the addition of such sugars. RJs from traditional sources and from industrial production by sugar feeding are thus successfully distinguished.

International audience; This paper presents the analysis of surfactants in complex mixtures using Raman spectroscopy combined with signal extraction (SE) methods. Surfactants are the most important component in laundry detergents. Both their identification and quantification are required for quality control and regulation purposes. Several synthetic mixtures of four surfactants contained in an Ecolabel laundry detergent were prepared and analyzed by Raman spectroscopy. SE methods, Independent Component Analysis and Multivariate Curve Resolution, were then applied to spectral data for surfactant identification and quantification. The influence of several pre-processing treatments (normalization, baseline correction, scatter correction and smoothing) on SE performances were evaluated by experimental design. By using optimal pre-processing strategy, SE methods allowed satisfactorily both identifying and quantifying the four surfactants. When applied to the pre-processed Raman spectrum of the Ecolabel laundry detergent sample, SE models remained robust enough to predict the surfactant concentrations with sufficient precision for deformulation purpose. Comparatively, a supervised modeling technique (PLS regression) was very efficient to quantify the four surfactants in synthetic mixtures but appeared less effective than SE methods when applied to the Raman spectrum of the detergent sample. PLS seemed too sensitive to the other components contained in the laundry detergent while SE methods were more robust. The results obtained demonstrated the interest of SE methods in the context of deformulation.

The aim of the work was to develop an analytical procedure able to quantify traces of 13 neonicotinoids and pyrethroids as well as carboxamide in beeswax at low levels (ng g−1) to evaluate the contamination. For this purpose, an efficient sample preparation procedure was developed based on solid–liquid extraction using dispersive diatomaceous earth and acetonitrile. This step was followed by a selective and sensitive analysis based on ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (ESI-MS/MS). This analytical procedure was validated based on International Conference on Harmonization guidelines. The limits of quantification ranged from 1 ng g−1 (thiamethoxam, clothianidin, imidacloprid, acetamiprid, thiacloprid and boscalid) to 40 ng g−1 (lambda-cyhalothrin). The method was then successfully applied to 60 samples of beeswax collected in several areas of France. The presence of thiacloprid, boscalid, imidacloprid and deltamethrin in beeswax was confirmed. The most frequently quantified pesticide was boscalid.

Chromatographic methods have made so much progress that they are today the method of choice in analytical laboratories. Not all molecules can be separated by the desired method. Derivatization reactions are simple chemical modification of the sample that will render it compatible with the selected separation method. Gas chromatography (GC) can separate volatile and thermostable compounds. The possible derivatization reactions that will enhance both volatility and thermal resistance of the solutes are summarized and the protocols are outlined. Liquid chromatography (LC) can separate solutes soluble in the mobile phase. The main problem is to detect them. Derivatization reactions in LC will modify the solutes adding a chomophore for easy UV detection or a fluorophore for sensitive fluorescent detection. Different protocols including pre- or postcolumn reactions are described. Capillary electrophoresis (CE) separates solutes by difference in electrophoretic mobility. Derivatization reactions in CE are similar to derivatization in LC when detection is the problem. On-column and postcolumn derivatizations are common in CE. Derivatization to change the solute electrophoretic mobility can also be performed. Keywords: adduct formation; capillary electrophoresis; chiral separations; derivatization; gas chromatography; liquid chromatography

International audience; Gas chromatography and liquid chromatography have been used simultaneously to analyze sugars in honey. After statistical processing by principal components analysis, additions of exogenous sugars could be detected by the appropriate fingerprints of adulteration. Application to acacia, chestnut and lavender honeys enabled the detection of fraud resulting from 5 to 10% addition of sugar syrups. This method may be considered as a replacement of isotopic analysis, that has some limitations.

We thank the beekeepers from GPGR for providing freshly harvested RJ samples and imported samples.; International audience; Royal jelly (RJ) is a high added value product, which can be spoiled and may lose its health-promoting properties according to the storage temperature and duration. Furosine, a compound generated at the early stages of the Maillard reaction, is a good marker of the freshness of RJ which can be used to detect heat treatments or prolonged storage of RJ samples. The determination of furosine content of RJ has been developed and validated by LC-MS. This new analytical method has the advantages of being sensitive and rapid. Moreover it avoids the time-consuming and cost-intensive SPE purification step of the usual HPLC-UV method. The influence of the storage temperature was studied on 55 French RJs. Ten of them were additionally analyzed just after harvest which exhibited furosine contents around 20.1 mg/100 g of protein. The furosine content remained stable when stored 9 months at −18 °C, whereas a slight increase was observed for a storage temperature of +2/+5 °C, with values increasing up to 61.3 mg/100 g of protein. The analysis of 27 commercial RJs, after 9 months of storage at +2/+5 °C, displayed higher furosine contents up to 219.9 mg/100 g of protein with a mean at 97.1 mg/100 g of protein. These results underline that furosine is a suitable marker for assessing the quality of storage conditions and freshness of RJ

International audience; The essential oil of Chrysanthemum coronarium (Garland) flowerheads was analyzed by gas chromatography-mass spectrometry and essayed for its in vitro scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and its antimicrobial activities against Escherichia coli, Salmonella typhymurium, Candida albicans, Bacillus cereus and Staphylococcus aureus. The aqueous extracts were tested for their allelopathic properties on seed germination and seedling growth of two annual weeds (Sinapis arvensis and Phalaris canariensis) and two crops (Triticum durum and Zea mays) and the identity of the phenolic components was determined by using HPLC-PDA-MS. A total of 40 components, representing 96.58% of the total oil were identified, and the most plentiful constituents were found to be cis-chrysanthenyl acetate (21.82%), trans-chrysanthenyl acetate (12.78%), (E)-β-farnesene (8.97%), germacrene-D (8.92%) and camphor (6.03%). The oil was unable to reduce the DPPH radical, while it exhibited a good antimicrobial activity against the gram-positive bacteria B. aereus and S. aureus. The aqueous extracts suppress the germination and reduce the seedling growth of the target species. The phytotoxic effect was found to be selective towards weeds with the effects being more pronounced in S. arvensis and P. canariensis. HPLC-PDA-MS analysis allowed the identification of chlorogenic acid acid, di-cafeoylquinic acids isomers, rutin, luteolin, luteolin-7-O-glucoside, myricetin-3-O-galactoside and tricin. The latter components were reported in C. coronarium for the first time. It is suggested that the identified components may be at least, a key factors in the observed phytotoxic activity and the data presented may contribute to the development of naturally occurring herbicides. Highlights The chemical composition of the essential oil of Chrysanthemum coronarium flowerheads was investigated. cis-Chrysanthenyl acetate, trans-chrysanthenyl acetate, (E)-β-farnesene, germacrene-D and camphor were the major components. The oil had a weak antioxidant and antimicrobial activities. The aqueous extract showed a strong and selective allelopathic activity against weeds. The main bioactive components di-cafeoylquinic acids isomers, luteolin-7-O-glucoside, myricetin-3-O-galactoside and tricin.

New biosourced chiral cross-linkers were reported for the first time in the synthesis of methyltestosterone (MT) chiral molecularly imprinted polymers (cMIPs). Isosorbide and isomannide, known as 1,4:3,6-dianhydrohexitols, were selected as starting diols. The cMIPs were synthesized following a noncovalent approach via thermal radical polymerization and monitored by Raman spectroscopy. These cross-linkers were fully characterized by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry. The cross-polarization magic angle spinning 13C NMR, Fourier transform infrared spectroscopy, scanning electron microscopy, and specific surface areas following the Brunauer-Emmett-Teller (BET) method were used to characterize the cMIPs. The effect of stereochemistry of cross-linkers on the reactivity of polymerization, morphology, and adsorption-recognition properties of the MIP was evaluated. The results showed that the cMIP exhibited an obvious improvement in terms of rebinding capacity for MT as compared with the nonimprinted polymer (NIP). The highest binding capacity was observed for cMIP-Is (27.298 mg g−1) for high concentrations (500 mg L−1). However, the isomannide homologue cMIP-Im showed higher recovery—up to 65% and capacity for low concentrations (15 mg L−1). The experimental data were properly fitted by the Freundlich adsorption isothermal model.

International audience; A gas chromatographic method was developed to quantify the major and minor sugars of 400 Royal Jellies (RJs). Their contents were compared in relation to the geographical origins and different production methods. A reliable database was established from the analysis of 290 RJs harvested in different French areas that took into account the diversity of geographical origin, harvesting season, forage sources available in the environment corresponding to natural food of the bees: pollen and nectar. Around 30 RJ samples produced by Italian beekeepers, about sixty-ones from French market, and around thirty-ones derived from feeding experiments were analysed and compared with our database. Fructose and glucose contents are in the range 2.3-7.8% and 3.4-7.7%, respectively, whatever the RJ's origin. On the contrary, differences in minor sugar composition are observed. Indeed sucrose and erlose contents in French RJs are lesser than 1.7% and 0.3%, respectively, whereas they reach 3.9% and 2.0% in some commercial samples and 5.1% and 1.7% in RJs produced from feeding experiments. This study could be used to discriminate different production methods and provide an additional tool for identifying unknown commercial RJs.

International audience; Isotope ratio mass spectrometry online coupled with capillary gas chromatography (GC-Py-IRMS) on column INNOWAX is used in the origin specific analysis and the authenticity control of the phenolic essential oils (EOs). Isotopic data delta(2)H(V-SMOW) of thymol and carvacrol in natural essential oils were evidently more depleted than synthetic products (from -49 to 7 per thousand for thymol and -61 per thousand for carvacrol). delta(2)H(V-SMOW) values of p-cymene, gamma-terpinene and thymol in authentic thyme oils (Thymus vulgaris L. and Thymus zygis L.) were found from -300 to -270 per thousand, from -285 to -248 per thousand and from -259 to -234 per thousand, respectively. delta(2)H(V-SMOW) values of carvacrol and p-cymene in authentic oregano oils (Origanum heracleoticum L., Coridothymus capitatus L. and Origanum compactum L.) varied from -223 to -193 per thousand and from -284 to -259 per thousand, respectively. For authentic Satureja montana subsp. montana essential oils, the mean delta(2)H(V-SMOW) value for aromatic compounds were found to be the following: gamma-terpinene -273 per thousand (SD=4.6 per thousand) and p-cymene -283 per thousand (SD=3.0 per thousand), thymol -245 per thousand (SD=1.8 per thousand) and carvacrol -226 per thousand (SD=1.7 per thousand). In addition, p-cymene was previously found as a precursor of the biosynthesis of thymol and carvacrol in thyme oil, thus, we considered p-cymene as an endogenous reference compound (ERC) for D/H ratio analysis. The isotopic fractionation factors alpha(thymol/p-cymene)=1.05 and alpha(carvacrol/p-cymene)=1.08 were obtained and also used to control the authenticity of the phenolic EOs.

International audience; Enantioselective capillary GC on a Supelco beta-DEX 225 column (heptakis(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-beta-cyclodextrin SPB 20poly--20% diphenyl, 80% dimethylsiloxane) and isotope-ratio mass spectrometry, coupled online with capillary GC on an HP5 column have been used for origin-specific analysis and authenticity control of essential oils, for example lemon (Citrus limon), lemongrass (Cymbopogon citratus and Cymbopogon flexuosus), citronella (Cymbopogon nardus L.--Ceylon type and Cymbopogon winterianus--Java type), Litsea cubeba, Lippia citriodora, lemon myrtle (Backhousia citriodora), lemon gum (Eucalyptus citriodora), and, especially, precious lemon balm oil (Melissa officinalis L.). Isotope data (delta13C(PDB) and delta2H(V-SMOW)) for citral (neral + geranial) and citronellal from on-line GC-C/Py-IRMS and chiral data for citronellal in these essential oils are reported. The possibility of using these data to determine the origin of these essential oils and to detect adulteration is discussed. Principal-components analysis (PCA) of specific compounds in two essential oils of lemongrass and Litsea cubeba was performed as a practical statistical method for distinguishing between these two types of oil.

International audience; The control of the floral quality of honey has become a priority issue as a result of the number of abuses observed and the relative ease of getting around existing control methods. We conducted chromatographic analyses of honey sugars to determine new criteria for authenticating an origin. The work involved creating databases by analysing a large number of authentic honeys from seven monofloral varieties, followed by statistical processing of the results by a principal components analysis. Differences in composition could thus be demonstrated, such as the presence of trisaccharides in fir honey, that provide an additional tool for authenticating unknow commercial honeys.

International audience; Honey samples were analyzed by stable carbon isotopic ratio analysis by mass spectrometry (SCIRA-MS) and site-specific natural isotopic fractionation measured by nuclear magnetic resonance (SNIF-NMR) to first determine their potentials for characterizing the substance and then to combat adulteration. Honey samples from several geographic and botanical origins were analyzed. The δ13C parameter was not significant for characterizing an origin, while the (D/H)I ratio could be used to differentiate certain single-flower varieties. Application of the official control method of adding a C4 syrup (AOAC official method 998.12) to our authentic samples revealed anomalies resulting from SCIRA indices that were more negative than -1‰ (permil). A filtration step was added to the experimental procedure and provided results that were compliant with the natural origin of our honey samples. In addition, spiking with a C4 syrup could be detected starting at 9-10%. The use of SNIF-NMR is limited by the detection of a syrup spike starting only at 20%, which is far from satisfying.

International audience; Amino acid analysis of honey by high-performance liquid chromatography (HPLC) was used first to discriminate different botanical origins and then to combat adulteration. Pure honeys of seven selected floral varieties were examined. A principal component analysis (PCA) was carried out on the results after selection of the most discriminating parameters. Lavender honeys were thus perfectly characterized, but complete satisfaction was not obtained with the six other varieties. This method (analysis by HPLC and statistical processing by PCA) enabled us to detect the addition of sugar syrup to rape and fir honeys.