References of "Lorge, Stéphanie"
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See detailOptimisation of a semiochemical slow-release alginate formulation attractive towards Aphidius ervi Haliday parasitoids
Heuskin, Stéphanie ULg; Lorge, Stéphanie; Godin, Bruno et al

in Pest Management Science (2011)

BACKGROUND: Optimisation of alginate formulations is described in order to develop semiochemical (E-β-farnesene and E-β-caryophyllene) slow-release devices in biological control approaches by attracting ... [more ▼]

BACKGROUND: Optimisation of alginate formulations is described in order to develop semiochemical (E-β-farnesene and E-β-caryophyllene) slow-release devices in biological control approaches by attracting predators and parasitoids of aphids. Various formulation criteria were optimised with respect to semiochemical encapsulation capacity. Moreover, the optimised formulation was characterised by texturometry and confocal microscopy. The slow-release rates of semiochemicals were calculated in laboratory controlled conditions. The attractiveness of semiochemical formulations towards Aphidius ervi was demonstrated by olfactometry. RESULTS: Two major parameters were highlighted in encapsulation optimisation: the type of alginate (Sigma L) and the type of crosslinker ion (Ca2+). Other formulation parameters were optimised: ionic strength (0.5M), Ca2+ (0.2 M) and alginate (1.5%) concentrations and the maturation time of beads in CaCl2 solution (48 h). After physical characterisation of beads, semiochemical slow-release measurements showed that alginate formulations were efficient sesquiterpene releasers, with 503 μg of E-β-farnesene and 1791 μg of E-β-caryophyllene totally released in 35 days. The efficiency of semiochemical alginate beads as attractants for female parasitoids was demonstrated, with high percentages of attraction for semiochemical odours (88 and 90% for E-β-farnesene and E-β-caryophyllene respectively) and significant statistical results. CONCLUSION: Semiochemical alginate beads can be considered as efficient slow-release systems in biological control. These formulations could be very useful to attract aphid parasitoids on crop fields. [less ▲]

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See detailDevelopment of biological control formulations incorporating components of plant origin
Heuskin, Stéphanie ULg; Lorge, Stéphanie; Verheggen, François ULg et al

in Journée Scientifique annuelle de la Société Royale de Chimie: Jeudi 14 octobre 2010, Gembloux Agro-Bio Tech, Université de Liège, Chimie verte (2010, October 14)

Semiochemicals – informative molecules used in insect-insect or plant-insect interactions – have been considered within various integrated pest management IPM strategies. Herein, two sesquiterpenoids: E-β ... [more ▼]

Semiochemicals – informative molecules used in insect-insect or plant-insect interactions – have been considered within various integrated pest management IPM strategies. Herein, two sesquiterpenoids: E-β-farnesene and E-β-caryophyllene have been formulated for their potential properties as aphid enemies attractants. Indeed, E-β-farnesene, the alarm pheromone of many aphid species [1], has also been identified as a kairomone by attracting and inducing oviposition of aphid predators (Episyrphus balteatus De Geer (Diptera: Syrphidae)) [2-5] and by attracting aphid parasitoids (Aphidius ervi Haliday (Hymenoptera: Braconidae)) [6, 7]. E-β-caryophyllene was identified as a potential component of the aggregation pheromone of the Asian ladybird, Harmonia axyridis Pallas [8, 9]. The two products have been purified from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae) [10, 11]. Natural and biodegradable slow-release devices have been investigated in order to deliver these molecules. Moreover, due to their sensitivity to oxidation, the sesquiterpenes needed to be protected. For this purpose, alginate (hydrophilic matrix with low oxygen permeability) was used as polymer for the formulations: the main objective was to hold and deliver semiochemical substances in a controlled way. Consequently, a careful selection of alginates was realised for encapsulation. Formulated beads showed different structural and encapsulation properties depending on factors such as polymer concentration, ionic strength, type and concentration of cross-linker ion,... The gel structure influenced diffusion properties. Alginate formulations were characterized by texturometry and by confocal microscopy in order to observe the distribution of semiochemicals in alginate network. The last step consisted in studying release rate of semiochemicals in laboratory-controlled conditions by adapted trapping and Fast-GC procedures [10,11]. [less ▲]

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See detailBiological control formulations incorporating essential oils' components
Heuskin, Stéphanie ULg; Lorge, Stéphanie; Wathelet, Jean-Paul ULg et al

in Lochynski, Stanislaw; Wawrzenczyk, Czeslaw (Eds.) 41th International Symposium on Essential Oils - Programme and Book of Abstracts (2010, September)

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See detailOptimisation of slow-release formulations as biological control devices
Heuskin, Stéphanie ULg; Lorge, Stéphanie; Debatty-Mestdagh, Michelle et al

Poster (2010, May 05)

E-β-Farnesene, the alarm pheromone of many aphid species and β-caryophyllene, recently identified as one of the possible component of the aggregation pheromones of the Asian ladybeetles Harmonia axyridis ... [more ▼]

E-β-Farnesene, the alarm pheromone of many aphid species and β-caryophyllene, recently identified as one of the possible component of the aggregation pheromones of the Asian ladybeetles Harmonia axyridis Pallas, are considered as two sesquiterpenes attractive for aphids’ predators and parasitoids, Epysirphus balteatus De Geer and Aphidius ervi Haliday, respectively. In the present research, alginate gel beads formulations were optimised as semiochemical slow-release devices. The formulations were evaluated in terms of volatiles release capacity, protection efficiency of sesquiterpenes against oxidation, and biological activity towards Epysirphus balteatus and Aphidius ervi. Moreover, the sesquiterpenes used in the formulations were obtained from natural matrices. Indeed, they were purified by flash chromatography fractionation of essential oils of Matricaria chamomilla L. and Nepeta cataria L., for obtaining E-β-farnesene and β-caryophyllene, respectively. The purities of the fractions were determined by means of a fast GC analytical method optimised for a good resolution of terpenes in less than five minutes. The experiments can conclude that the alginate gel beads formulations are efficient as biological control devices considering the results obtained with the various biological tests led on predators and parasitoids. Moreover, the sesquiterpenes are more protected when formulated in alginate beads than without formulation. The devices allow also a slow-release of semiochemicals during a long time (at least 40 days) depending on physico-chemical parameters (temperature, relative humidity). A mathematical modelisation of semiochemicals release is presently in study. [less ▲]

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See detailA fast gas chromatographic method for the study of semiochemical slow release formulations
Heuskin, Stéphanie ULg; Lorge, Stéphanie; Leroy, Pascal ULg et al

Poster (2010, January)

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See detailValidation of a fast gas chromatographic method for the study of semiochemical slow release formulations
Rozet, Eric ULg; Heuskin, Stéphanie ULg; Lorge, Stéphanie et al

in Journal of Pharmaceutical & Biomedical Analysis (2010), 53

The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-β-farnesene and β-caryophyllene) to be used in an integrated pest management ... [more ▼]

The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-β-farnesene and β-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days. [less ▲]

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See detailContribution to the study of semiochemical slow release formulations. Development of flash chromatographic methods.
Heuskin, Stéphanie ULg; Farmakidis, Julien; Lorge, Stéphanie et al

Poster (2009)

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