Optimization of a method for preparing solid complexes of essential clove oil with ß-cyclodextrins.

BACKGROUND: Clove oil (CO) is an aromatic oily liquid used in the food, cosmetics and pharmaceutical industries for its functional properties. However, its disadvantages of pungent taste, volatility, light sensitivity and poor water solubility can be solved by applying microencapsulation or complexation techniques. RESULTS: Essential CO was successfully solubilized in aqueous solution by forming inclusion complexes with ß-cyclodextrins (ß-CDs). Moreover, phase solubility studies demonstrated that essential CO also forms insoluble complexes with ß-CDs. Based on these results, essential CO-ß-CD solid complexes were prepared by the novel approach of microwave irradiation (MWI), followed by three different drying methods: vacuum oven drying (VO), freeze-drying (FD) or spray-drying (SD). FD was the best option for drying the CO-ß-CD solid complexes, followed by VO and SD. CONCLUSION: MWI can be used efficiently to prepare essential CO-ß-CD complexes with good yield on an industrial scale. © 2016 Society of Chemical Industry.

Use of cyclodextrins to recover catechin and epicatechin from red grape pomace.

The capacity of cyclodextrins (CDs) to extract phenolic compounds from grape pomace was evaluated and compared with that of ethanol/water or aqueous extraction. The extraction method (stirring and ultrasound), temperature and time were also studied. Total phenolic compounds (TPC) and antioxidant activity were measured, and HPLC analysis was used to identify the phenolic compounds. The extracts obtained using the ethanol/water mixture presented the highest TPC content and antioxidant activity, followed by those obtained using CD solutions. The addition of CDs to the extractant agent had a selective effect on the extraction of catechin and epicatechin. The yield of catechin and epicatechin by using aqueous solutions of CDs was similar to that obtained using organic solvents as ethanol.