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In this study, star anise (Illicium verum) essential oils (SAEOs) were extracted by hydrodistillation (HD), ethanol solvent extraction (ESE), supercritical CO2 (SCD) and subcritical extraction (SE) via electronic nose (E-nose), gas chromatography-mass spectrometry (GC-MS), and GC-ion mobility spectrometry (GC-IMS). GC-MS and GC-IMS were used to identify the volatile compounds, and GC-MS was also used to determine their concentrations. Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to visualise volatile compounds and differentiate samples. The results showed that anethole and limonene were the main volatile compounds in SAEOs extracted using the four methods and their components were similar, albeit in different proportions. In addition, the fingerprints of their volatile components were established via E-nose and GC-IMS analyses. In general, GC-MS, GC-IMS, and E-nose combined with PCA and LDA analysis could accurately distinguish SAEOs extracted using different extraction methods, and GC-IMS was identified as the most suitable method because of its accuracy and rapidity. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) have good natural antioxidant and antimicrobial properties; however, their volatility, intense aroma, poor aqueous solubility, and chemical instability limit their applications in the food industry. The encapsulation of EOs in β-cyclodextrins (β-CDs) is a widely accepted strategy for enhancing EO applications. The complexation of cinnamon essential oil (CEO) with five types of β-CDs, containing different substituent groups (β-CD with primary hydroxyl, Mal-β-CD with maltosyl, CM-β-CD with carboxymethyl, HP-β-CD with hydroxypropyl, and DM-β-CD with methyl), inclusion process behaviors, volatile components, and antioxidant and antibacterial activities of the solid complexes were studied. The CEOs complexed with Mal-β-CD, CM-β-CD, and β-CD were less soluble than those complexed with DM-β-CD and HP-β-CD. Molecular docking confirmed the insertion of the cinnamaldehyde benzene ring into various β-CD cavities via hydrophobic interactions and hydrogen bonds. GC-MS analysis revealed that HP-β-CD had the greatest adaptability to cinnamaldehyde. The CEO encapsulated in β-, Mal-β-, and CM-β-CD showed lower solubility but better control-release characteristics than those encapsulated in DM- and HP-β-CD, thereby increasing their antioxidant and antibacterial activities. This study demonstrated that β-, Mal-β-, and CM-β-CD were suitable alternatives for the encapsulation of CEO to preserve its antioxidant and antibacterial activities for long-time use. [ABSTRACT FROM AUTHOR]

Compared with traditional liquid–liquid embedding method and solid–liquid embedding method of inclusion complexes of β‐cyclodextrin (β‐CD) inclusion of essential oil to form stable properties, the gas–liquid embedding method was applied to encapsulate vaporized illicium verum essential oil (IvEO), with β‐CD as wall materials so that core and wall materials molecules are in active state during complexing process. At optimal conditions with a mass ratio of 1:10, temperature of 80°C, time of 1 h, the β‐CD‐IvEO inclusion complexes (β‐CD‐IvEO‐ICs) had an encapsulation efficiency (EE) of 84.55 ± 2.31%. Fourier transform infrared spectroscopy (FTIR) revealed the encapsulation of IvEO into inclusion complexes, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) demonstrated the enhanced thermal stability of IvEO after embedding. Furthermore, the reducing power and 2‐phenyl‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide (PTIO)‐scavenging capacity displayed certain capacity of antioxidation in a short time but stronger antioxidative activities as reaction time was extended. The diameter of growth zone (DGZ) indicated stronger antibacterial activity of β‐CD‐IvEO‐ICs against Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. Moreover, the β‐CD‐IvEO‐ICs could induce the bacteria producing more reactive oxygen species (ROS) than IvEO, resulting in bacterial death. [ABSTRACT FROM AUTHOR]

Plant essential oils have excellent antioxidant and antibacterial properties, which can greatly reduce microbial resistance. However, the odor and cost issues caused by their high concentration use remain the main bottlenecks in their application as antibacterial agents. The present study was conducted to evaluate inhibitory activity of essential oils (EOs) against Escherichia coli and Staphylococcus aureus, and focus on synergistic activity of EOs against Malassezia furfur. The minimum inhibitory concentrations and the active components of various EOs and their combination were determined using the agar dilution method and gas chromatography–mass spectrometry, respectively. The synergistic effect of EO combination on Malassezia furfur was evaluated by analyzing its growth, morphology, and cell membrane fluidity using growth curve analyses, scanning electron microscopy, and N-phenyl-1-naphthylamine method, respectively. Additionally, the antioxidant activity of the EOs combination was evaluated using the free radical scavenging method. The mixture of EOs exerted a synergistic effect on M. furfur , causing logarithmic growth phase lag, cell damage, decreased membrane fluidity, and the mixture of EOs also had synergistic effect on DPPH free radical scavenging. Conclusively, the combination of EOs investigated in this study exhibited good antibacterial ability against M. furfur, may have potential applications in seborrheic dermatitis. • CEO and TEO had synergistic effect on antimicrobial activities, DPPH free radical scavenging. • Escherichia coli , Staphylococcus aureus and Malassezia furfur were inhibited. • The synergistic effect reduced the required doses of essential oil. [ABSTRACT FROM AUTHOR]