Spectroscopic examination and release of microencapsulated oregano essential oil

Abstract

<jats:p>&lt;p class="ADMETkeywordsheading"&gt;&lt;em&gt;Oregano essential oil (EO) of Greek origin with high carvacrol content (86.84 %) was encapsulated by spray drying using Arabic gum, modified starch and maltodextrin (75:12.5:12.5) as wall materials. The spray-dried product (EOSD) consisted of roundish particles with narrow size distribution. FT-IR and Raman spectroscopy identified the EO in EOSD, with Raman spectra showing more distinct peaks and a small shift of the peak at 1260 cm&lt;sup&gt;-1&lt;/sup&gt; (assigned to the stretching vibration of the bond of C-O of the phenol), implying only minor chemical interaction with the wall materials. Release of the EO from EOSD was described by the Hixson-Crowell equation (R&lt;sup&gt;2&lt;/sup&gt;=0.986) with apparent diffusion coefficient 8.3x10&lt;sup&gt;-10 &lt;/sup&gt;m&lt;sup&gt;2&lt;/sup&gt;/s. These findings indicate that microencapsulation by spray drying did not affect the quality of the oregano EO and provided relatively fast and complete release. &lt;/em&gt;&lt;/p&gt;</jats:p>

Improvement of the Antimicrobial Activity of Oregano Oil by Encapsulation in Chitosan—Alginate Nanoparticles

“…However, an interaction between the oregano oil and the chitosan-alginate nanoparticles is not excluded because of the changed intensity and the appearance of new peaks. Similar interaction is observed for microencapsulated oregano oil using acacia, starch, and maltodextrin [63].…”

Bioactive Properties of Nanofibres Based on Concentrated Collagen Hydrolysate Loaded with Thyme and Oregano Essential Oils

“…By incorporation of thyme and oregano essential oils into collagen hydrolysate (P2 and P3 samples), both spectra show the typical pattern of protein molecules, suggesting that the prominent bands characteristic of essential oils were overlapped with the characteristic bands of collagen. The peaks that are common in the FT-IR spectra for thyme and oregano essential oils are ascribed at: 2960 cm −1 to antisymmetrical -CH 3 stretching vibration, 1419 cm −1 to antisymmetrical -CH 3 bending and 1226-1289 cm −1 to C-O-C stretching [46] and 940-945 cm −1 γ-terpinene [47].…”

“…ATR-FTIR spectra for thyme essential oil, oregano essential oil, collagen nanofibres and collagen loaded with thyme essential oil and oregano essential oil are presented in Figure 5. The peaks that are common in the FT-IR spectra for thyme and oregano essential oils are ascribed at: 2960 cm −1 to antisymmetrical -CH3 stretching vibration, 1419 cm −1 to antisymmetrical -CH3 bending and 1226-1289 cm −1 to C-O-C stretching [46] and 940-945 cm −1 ɣ-terpinene [47].…”

Submicron-Sized Vermiculite Assisted Oregano Oil for Controlled Release and Long-Term Bacterial Inhibition

“…The characteristic peaks at 1054, 1116 and 1172 cm −1 were attributed to para-substitution of p -cymene, ortho-substitution of carvacrol and meta-substitution of thymol, respectively [ 39 ]. The characteristic peaks at (1243, 1297 cm −1 ) and (1423, 1459 cm −1 ) can be attributed to the C-O stretching [ 64 , 65 ] and C=C aromatic vibration [ 36 ] of the active components. The characteristic peaks at 1356, 1507, 1583 were attributed to the asymmetric bending of the isopropyl group, C=C stretching carvacrol, thymol and p -cymene [ 39 ].…”