Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2021
A comparative study on surface/interface mechanism and antibacterial properties of different hybrid materials prepared with essential oils active ingredients and palygorskite
Abstract
Abstract Six active ingredients of essential oils were chosen to prepare organic/inorganic antibacterial hybrid materials based on natural palygorskite by mechanical grinding. Fourier transform infrared spectroscopy, X-ray diffraction and Thermo gravimetric analysis were employed to comparatively study the stability of different organic/inorganic hybrid materials, and the density functional theory calculation revealed that the key factor for formation of the stable hybrid materials was ascribed to the hydrogen bond between the oxygen-containing group of the essential oils ingredients and the Si-OH and Mg-OH2 groups of palygorskite. The minimum inhibitory concentration value against Escherichia coli and Staphylococci aureus was measured to test the antibacterial activity of hybrid materials. It was found that thymol/palygorskite hybrid materials exhibited the best antibacterial activity with the minimum inhibitory concentration values of 2.0\xa0mg/mL, which was equal to that of carvacrol/palygorskite due to the similar molecular structures of thymol and carvacrol. Furthermore, the cymene/palygorskite, limonene/palygorskite and terpinene/palygorskite hybrid materials show a better bioavailability than their corresponding essential oils ingredients due to the increase in their hydrophilia and dispersion in aqueous solution. Based on the understanding on the surface/interface mechanism of essential oils ingredients and palygorskite, it is expected to guide the preparation of stable green antibacterial materials with excellent antibacterial activity combining with natural palygorskite and essential oils ingredients.