| Cyclodextrins (CDs) possess a hydrophilic exterior and a hydrophobic cavity. These properties enable CDs can include many guest molecules by size-fit effect and hydrophobic interaction. The solubility, chemical stability, release rate and the bioavailability of agrochemicals would be improved markedly by the formation of inclusion complexes, so CDs have important value in agrochemical formulation. In addition, CDs can promote the degradation of agrochemicals, at the same time, they can selectively recognize the agrochemical molecules. Therefore, they have very important applications in separating chiral agrochemicals and determinating agrochemical residues.However, CDs inclusion complex as a dosage form in the application of agrochemicals is still less. With increasing demands on the environment, the relationship between the biological activity and the structure of a compound was paid more attention. "More efficient" will become a direction of development of modern agrochemicals in the future. Therefore, it is meaningful and valuable to introduce CDs inclusion complex in the agricultural field.The dissertation includes following four chapters:Chapter 1:Introduction. A brief review of investigation progress of CDs inlusion complex on agriculture was summarized.Chapter 2:Study on inclusion complexation between plant growth regulator 6-benzylaminopurine andβ-cyclodextrin:Preparation, characterization and molecular modeling. An inclusion complex between the plant growth regulator 6-benzylaminopurine (6-BA) and (3-cyclodextrin (β-CD) was prepared. To reveal the inclusion interaction, phase solubility studies, thermoanalysis. NMR and FT-1R spectra were applied to characterize the formation of the complex. The stoichiometry was conformed by both elemental analysis and Job's plot. One-dimensional'H NMR and ROESY experiments indicated the mode of the complex in which the benzene ring of 6-BA was encapsulated within the f3-CD cavity. Furthermore, the molecular modeling studies including molecular docking and molecular dynamics simulations were implemented to built the three-dimensional mode of the complex. By complexation withβ-CD, the water solubility and the thermal stability of 6-BA were significantly improved, which will enlarge its application in the field of agriculture and gardening.Chapter 3:Inclusion complexation of chloropropham withβ-cyclodextrin:preparation, characterization and molecular modeling. An inclusion complex between the agrochemical chloropropham (CIPC) andβ-CD was prepared. Elemental analysis, phase solubility studies, FT-1R, thermoanalysis and1H NMR were applied to characterize the complex, indicating that the main driving forces of the complexation were hydrophobic interactions and hydrogen bonds. The experimental results showed that the structure of the complex was two (3-CD molecules respectively included one CIPC molecule's chlorphenyl and isopropyl moiety, which were confirmed by molecular modeling studies. The complexation of CIPC with (3-CD significantly improved the thermal stability and water solubility of CIPC. It supplied a new formation of agrochemical CIPC.Chapter 4:Study on inclusion complexation between carbendazim (MBC) and hydroxypropyl-β-cyclodextrin (HP-β-CD):preparation, characterization and fungicidal activity. The effect of HP-β-CD on the improvement of the fungicidal activity of MBC has been investigated. The inclusion complexation of HP-β-CD with MBC has been prepared and characterized by phase solubility diagram, fluorescence,'H NMR and FT-IR spectra. The stoichiometric ratio and stability constant were determined by Job" plot and phase solubility studies, respectively. The inclusion complex MBCHP-β-CD has exhibited different properties from MBC. The obtained inclusion complex was found to significantly improve the water solubility of MBC. In addition, the antibacterial activity indicated that the complex displayed the better fungicidal activity than MBC. The present study provided useful information for a more rational application of MBC.
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