Cold nitrogen plasma modified cuminaldehyde/β-cyclodextrin inclusion complex and its application in vegetable juices preservation

Abstract

E. coli O157:H7 is one of the most common food-borne pathogens and usually related to contaminated vegetables. This study was to prepare an effective antibacterial agent and applied in vegetable juices. In this study, β-cyclodextrin inclusion complexof CUM (CUM /βCD-IC) was prepared using ultrasonication technique and then treated with cold nitrogen plasma (CNP) to observe its effect in the physicochemical and antibacterial properties of CUM/βCD-IC. Various characterization techniques such as fluorescence, fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) confirmed the formation of IC between CUM and βCD. Phase solubility and double reciprocal profiles studies proved the enhanced solubility of CUM with increasing amount of βCD and the guest/host stoichiometry of 1:1. Computational modeling and FT-IR indicated that the phenyl ring with isopropyl chain of CUM is inserted in the hydrophobic βCD. Investigations of thermal properties proved that the βCD-IC formation improved the stability of CUM. Antibacterial test results indicated that CNP-CUM/βCD-IC exhibited better antibacterial activity than CUM/βCD-IC. After CNP-CUM/βCD-IC treatment, it was observed by TEM that the cell membrane of E. coli O157:H7 was broken. In addition, the antibacterial activity of CNP-CUM/βCD-IC in vegetable juices was carried out and the findings revealed that CNP-CUM/βCD-IC has an excellent antibacterial effect on vegetable juices.