In vitro antioxidant and antidiabetic activity of essential oils encapsulated in gelatin-pectin particles against sugar, lipid and protein oxidation and amylase and glucosidase activity

The in vitro antioxidant and antidiabetic activities ofOliveria decumbens,Thymus kotschyanus,Trachyspermum ammi, andZataria multifloraessential oils incorporated into gelatin-pectin composite were investigated. The gas chromatography-mass spectrometry characterization revealed that thymol (1.2%-86.4%), carvacrol (3.2%-52.4%), gamma-terpinene (0.0%-12.7%), para-cymene (3.2%-5.2%), geraniol (0.0%-14.5%), and spathulenol (0.0%-13.6%) are the major constituents of the essential oils. Gelatin-pectin composite incorporated with the essential oils exhibited acidic pH (2.40-3.04), low conductivity (265-278 mu S/cm), low surface tension (19.0-23.5 mN/m), low Newtonian viscosity (23.7-28.5 mPa.s), negative zeta-potential (14.2-16.9 mV), and nanoscale particle size (313-336 nm). These rheological properties result in the production of globular gelatin-pectin nanoparticles with a size range of 500-700 nm. The FTIR spectra of gelatin-pectin and gelatin-pectin-essential oils to some extent were similar, suggesting the noncovalent interactions between them. Gelatin-pectin composite incorporated with the essential oils displayed antiglucose oxidation (130-150 mu g/ml) antilipid peroxidation (120-130 mu g/ml), antiprotein oxidation (150-168 mu g/ml), and antiprotein glycation (145-170 mu g/ml) as well as antiamylase (216-230 mu g/ml), and antiglucosidase (212-238 mu g/ml) activity. The essential oils strongly improved the antioxidant capacity of the gelatin-pectin composite so strongly which can be recommended as a natural compound for oxidative stress management.