Beta-Cyclodextrin (beta-CD) is an amphipathic toroid consisting of seven D-(+)-glucopyranose units linked by beta-(1-4) bounds with a hydrophobic cavity that is capable of forming inclusion complex with hydrophobic guests of suitable size and shape and an outer hydrophilic surface [1]. Beta-CD has the ability to form inclusion complexes resulting in significant improvement in water solubility and stability of the guest molecule whose taste and odor are partially masked. Beta-CD is produced from a renewable natural material (starch) by a sustainable biotechnological process, it is commercially available in large bulk at relatively cheap price, it is nontoxic in consumable concentration and it is biodegradable. Its use in pharmaceutical, textile, food industry and recently in cosmetics and detergents is widely known, however, a few examples are present in agriculture as sustainable matrix to improve agrochemicals effect. Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), spotted-wing drosophila, has recently become a common and serious pest of temperate fruit crops (small fruits, cherries and kaki) in many countries [2]. Crop damage is caused when adult females, using a serrated ovipositor, lay eggs in ripe and partially ripe fruit before harvest. Developing larvae cause soft and unmarketable fruit, moreover oviposition wounds provide access to pathogens that may enhance fruit deterioration leading to increased risk of secondary rot infections with an economic losses up to 80%. Push-pull strategies (stimulus deterrent diversionary strategies) attempt to reduce crop injury by modifying pest distribution using adversative stimuli to push the pest organism away from the crop while also using attractive stimuli to pull the pest organism out of the crop [3]. A novel and more sustainable method for repelling D. suzukii was evaluated by spraying edible repellents (alone and in mixture) on fruit surface during ripening period in combination with conventional natural attractive traps. The project, started in March 2018, join expertise in organic chemistry, physical chemistry, entomology, insect physiology and crop protection. Both edible repellents and synergists were selected from commercially available natural occurring compounds and their inclusion complexes with beta-cyclodextrin (betaCD) were prepared under sustainable conditions. All beta-CD complexes were characterized by 1NMR spectroscopy and release time of the guest were calculated in aqueous solution. Preliminary studies on effectiveness of complexes were carried out with laboratory-reared D. suzukii on artificial fruits. Under electrophysiological assay D. suzukii appeared to be sensitive to all selected edible repellents. Field experiments have been planned.
Beta-CYCLODEXTRIN INCLUSION COMPLEXES OF NATURAL OCCURRING COMPOUNDS AND THEIR EVALUATION AS INSECT REPELLENTS IN A PUSH-PULL STRATEGY
M A Dettori;D Fabbri;L Loru;G Delogu
2018
Abstract
Beta-Cyclodextrin (beta-CD) is an amphipathic toroid consisting of seven D-(+)-glucopyranose units linked by beta-(1-4) bounds with a hydrophobic cavity that is capable of forming inclusion complex with hydrophobic guests of suitable size and shape and an outer hydrophilic surface [1]. Beta-CD has the ability to form inclusion complexes resulting in significant improvement in water solubility and stability of the guest molecule whose taste and odor are partially masked. Beta-CD is produced from a renewable natural material (starch) by a sustainable biotechnological process, it is commercially available in large bulk at relatively cheap price, it is nontoxic in consumable concentration and it is biodegradable. Its use in pharmaceutical, textile, food industry and recently in cosmetics and detergents is widely known, however, a few examples are present in agriculture as sustainable matrix to improve agrochemicals effect. Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), spotted-wing drosophila, has recently become a common and serious pest of temperate fruit crops (small fruits, cherries and kaki) in many countries [2]. Crop damage is caused when adult females, using a serrated ovipositor, lay eggs in ripe and partially ripe fruit before harvest. Developing larvae cause soft and unmarketable fruit, moreover oviposition wounds provide access to pathogens that may enhance fruit deterioration leading to increased risk of secondary rot infections with an economic losses up to 80%. Push-pull strategies (stimulus deterrent diversionary strategies) attempt to reduce crop injury by modifying pest distribution using adversative stimuli to push the pest organism away from the crop while also using attractive stimuli to pull the pest organism out of the crop [3]. A novel and more sustainable method for repelling D. suzukii was evaluated by spraying edible repellents (alone and in mixture) on fruit surface during ripening period in combination with conventional natural attractive traps. The project, started in March 2018, join expertise in organic chemistry, physical chemistry, entomology, insect physiology and crop protection. Both edible repellents and synergists were selected from commercially available natural occurring compounds and their inclusion complexes with beta-cyclodextrin (betaCD) were prepared under sustainable conditions. All beta-CD complexes were characterized by 1NMR spectroscopy and release time of the guest were calculated in aqueous solution. Preliminary studies on effectiveness of complexes were carried out with laboratory-reared D. suzukii on artificial fruits. Under electrophysiological assay D. suzukii appeared to be sensitive to all selected edible repellents. Field experiments have been planned.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
