title: Encapsulation of tea tree oil by amorphous beta-cyclodextrin powder.
abstract: An innovative method to encapsulate tea tree oil (TTO) by direct complexation with solid amorphous beta-cyclodextrin (β-CD) was investigated. A β-CD to TTO ratio of 90.5:9.5 (104.9mg TTO/g β-CD) was used in all complexation methods. The encapsulation was performed by direct mixing, and direct mixing was followed by the addition of water (13-17% moisture content, MC) or absolute ethanol (1:1, 1:2, 1:3 and 1:4 TTO:ethanol). The direct mixing method complexed the lowest amount of TTO (60.77mg TTO/g β-CD). Powder recrystallized using 17% MC included 99.63mg of TTO/g β-CD. The addition of ethanol at 1:2 and 1:3 TTO:ethanol ratios resulted in the inclusion of 94.3 and 98.45mg of TTO/g β-CD respectively, which was similar to that of TTO encapsulated in the conventional paste method (95.56mg TTO/g β-CD), suggesting an effective solid encapsulation method. The XRD and DSC results indicated that the amorphous TTO-β-CD complex was crystallized by the addition of water and ethanol.
authors.affiliation: School of Agriculture and Food Sciences, The University of Queensland, QLD 4072, Australia.
authors.forename: Meena
authors.initials: M
authors.lastname: Shrestha
authors.affiliation: School of Agriculture and Food Sciences, The University of Queensland, QLD 4072, Australia.
authors.forename: Thao M
authors.initials: TM
authors.lastname: Ho
authors.affiliation: School of Agriculture and Food Sciences, The University of Queensland, QLD 4072, Australia. Electronic address: b.bhandari@uq.edu.au.
authors.forename: Bhesh R
authors.initials: BR
authors.lastname: Bhandari
mesh_terms: D000431:Ethanol / Q000737:chemistry*; D011208:Powders; D020947:Tea Tree Oil / Q000737:chemistry*; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D011208:Powders; D047392:beta-Cyclodextrins; D000431:Ethanol; D020947:Tea Tree Oil
keywords: Amorphous β-cyclodextrin powder; Crystallization; Ethanol; Molecular encapsulation; Tea tree oil