Insights from Syzygium aromaticum Essential Oil: Encapsulation, Characterization, and Antioxidant Activity

• Published in: Pharmaceuticals (Basel, Switzerland) Vol. 17; no. 5; p. 599
• Main Authors: Mergulhão, Naianny L O N, Bulhões, Laisa C G, Silva, Valdemir C, Duarte, Ilza F B, Basílio-Júnior, Irinaldo D, Freitas, Johnnatan D, Oliveira, Adeildo J, Goulart, Marília O F, Barbosa, Círia V, Araújo-Júnior, João X
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 08.05.2024
• Subjects: alginate; Antioxidants; clove essential oil; eugenol; Food; freeze drying; Humidity; ionic gelation; Moisture content; Oils & fats; Oxidation; Pharmaceutical industry; Polymers; Solvents; alginate; ionic gelation; eugenol; freeze drying; clove essential oil
• ISSN: 1424-8247; 1424-8247
• DOI: 10.3390/ph17050599

Alginate encapsulates loaded with clove essential oil (CEO) were prepared by ionic gelation, with subsequent freeze-drying. The objective of the present work was to develop a product with the ability to protect CEO against its easy volatility and oxidation. The following techniques were used to characterize the formulations: eugenol release, degree of swelling, GC/MS, TGA/DSC, and SEM. The alginate solution (1.0%) containing different concentrations of CEO (LF1: 1.0%; LF2: 0.5%; LF3: 0.1%) was dropped into a 3.0% CaCl solution. After lyophilization, the encapsulated samples were wrinkled and rigid, with high encapsulation power (LF3: 76.9% ± 0.5). Three chemical components were identified: eugenol (the major one), caryophyllene, and humulene. The antioxidant power (LF1: DPPH IC 18.1 µg mL ) was consistent with the phenol content (LF1: 172.2 mg GAE g ). The encapsulated ones were thermally stable, as shown by analysis of FTIR peaks, eugenol molecular structure was kept unaltered. The degree of swelling was 19.2% (PBS). The release of eugenol (92.5%) in the PBS solution was faster than in the acidic medium. It was concluded that the low-cost technology used allows the maintenance of the content and characteristics of CEO in the three concentrations tested, offering a basis for further research with essential oil encapsulates.