Modified cyclodextrin type and dehydration methods exert a significant effect on the antimicrobial activity of encapsulated carvacrol and thymol

Abstract

BACKGROUND The antimicrobial activity of essential oils and their constituents has led to increasing interest in using them as natural preservative agents. However, their high sensitivity to light and oxygen, their volatility and their low aqueous solubility are all obstacles to their application in the food, cosmetic or pharmaceutical industries. Encapsulation in cyclodextrins (CDs) is a solution for the application of such essential oils. RESULTS The complexation of carvacrol and thymol with hydroxypropyl (HP)‐α‐, HP‐β‐ and HP‐γ‐CD, the behavior of the solid complexes prepared by freeze‐drying and spray‐drying methods and the antibacterial activity of solid complexes were studied. Kc values of HP‐α‐ and HP‐γ‐CD complexes with carvacrol (118.4 and 365.7 L mol−1) and thymol (112.5 and 239.7 L mol −1) were far lower than those observed for HP‐β‐CD complexes with carvacrol (2268.2 L mol −1) and thymol (881.6 L mol −1). The lower stability of HP‐α‐ and HP‐γ‐CD complexes increased the release of compounds, thereby affecting the antimicrobial activity of carvacrol and thymol to a lesser extent than complexation with HP‐β‐CD, normally used in the encapsulation of carvacrol and thymol. HP‐β‐CD encapsulation of carvacrol and thymol markedly reduced their antimicrobial activity. The freeze‐drying method barely affected the antimicrobial activity of carvacrol and thymol after encapsulation, while spray drying could be considered for the production of solid complexes in combination with the appropriate CD. CONCLUSIONS It was thus demonstrated that HP‐α‐ and HP‐γ‐CD are very suitable alternatives for the encapsulation of carvacrol and thymol with the purpose of preserving their bacteriostatic and bactericidal activities. © 2020 Society of Chemical Industry

Oleanolic Acid Complexation with Cyclodextrins Improves Its Cell Bio-Availability and Biological Activities for Cell Migration

“…The dehydration yield (DY) values were around 90% for both CDs. These values indicate a high level of complex recovery and were similar to those previously obtained in complex dehydration using the freeze drying technique [43].…”

“…Cyclodextrins are natural macromolecules that show a unique tridimensional structure; they have a hydrophilic surface that confers high water solubility and a hydrophobic cavity that encapsulates a wide variety of hydrophobic compounds [39][40][41][42]. Many authors have shown the potency of cyclodextrins to deliver drugs since they reinforce their biological activities [39,[43][44][45][46][47]. There are three types of native cyclodextrins, α, β, and γ, that differ in the number of D-glucose units that formed them, 6, 7, or 8, respectively, which progressively increase the size of the hydrophobic cavity [48].…”

Cyclodextrin Derivatives as Promising Solubilizers to Enhance the Biological Activity of Rosmarinic Acid

“…Depending on the compound to be incorporated into the cavity of the CD, the effect of different CDs on the solubility of the molecule can vary; for example, in the case of curcumin, HP-β-CD caused an increase in solubility ~57 times, while better results were obtained for HP-γ-CD, which caused an increase in solubility ~123 times [ 43 , 44 ]. In another study, HP-α-CD, HP-β-CD, and HP-γ-CD impacted the solubility of phenolic monoterpenes thymol and carvacrol [ 45 ]. For both substances, the most efficient increase in solubility was caused by the influence of HP-β-CD.…”

Preparation of PET‐EG‐β‐CD mat for the preservation of chilled pork

“…β ‐cyclodextrin ( β ‐CD) was a relatively mature wall material, which had the advantages of loading hydrophobic and hydrophilic substances, low cost and low toxicity (Liu et al ., 2008). Santiago et al have demonstrated that carvacrol embedding in cyclodextrins and their derivatives could decrease volatility, and increase its oxidation and antimicrobial activity (López‐Miranda et al ., 2021). Although there were some studies on antimicrobial mats or embedding β ‐CD, little was known about the effect of adding EG to β ‐CD‐PET on meat preservation.…”