Preparation, characterization, and antifungal activity of (E)-2-octenal/β-cyclodextrin inclusion complex against the blue mold in citrus fruit caused by a prochloraz-resistant Penicillium italicum strain

AimsTo overcome the hydrophobicity and effumability restriction of the essential oil in practice, we aim to fabricate the (E)-2-octenal-β-cyclodextrin inclusion complex (O/β-CDIC) and investigate its encapsulation mechanism.Methods and ResultsThe O/β-CDIC was fabricated using saturated aqueous solution method combined with freeze-dried method. The encapsulation efficiency and loading content of O/β-CDIC were 45.61 ± 1.37% and 2.97 ± 0.08%. In vitro assays, the MIC (Minimum Inhibitory Concentration) and MFC (Minimum Fungicidal Concentration) of the O/β-CDIC were 2.00 and 8.00 mg·mL⁻¹ for P. italicum XX5 mycelial growth, respectively. In addition, the O/β-CDIC effectively reduced the incidence of blue mold in citrus fruit and maintained fruit quality. The detailed structure characterization combined with the molecular docking study, molecular electrostatic potential, and independent gradient model based on Hirshfeld analysis collectively demonstrated that (E)-2-octenal was entrapped successfully within the β-CD cavity.ConclusionsThe O/β-CDIC significantly enhanced the thermal stability and phase solubility of (E)-2-octenal while effectively preserving its antifungal activity. Characterization analyses confirmed the presence of non-covalent interactions between β-CD and (E)-2-octenal.