## 4 Essential Oils as Active Secondary Compounds in Wound Dressings
An in-vitro antibacterial test proved that the thyme-formulated films could limit the growth of _Escherichia coli_ and _Staphylococcus aureus_. Viable cell counting demonstrated the antibacterial effect of nanoemulsion-films, and the release profile showed a controlled kinetic during the time (150 h) after an initial burst. Furthermore, the good value obtained by the tensile strength test confirmed these biomaterials suitable as wound dressings [103]. Oregano (_Origanum vulgare_) is a plant from the unit family native to Western and Southwestern Eurasia and the Mediterranean region. Turmeric (_Curcuma longa_) is in the ginger family and a native plant to the Indian subcontinent and southeast Asia. The essential oils of these plants have potential applications in wound healing because of their antimicrobial and antioxidant ability (Figure 3) [146]. In this respect, [PERSON] et al. fabricated different types of dressings (ointment, hydrogel, and nanofiber) with 5% turmeric, 1% oregano, and 1% chitosan nanoparticles and compared their antibacterial, antioxidant, and cytotoxicity properties with those of commercial alginate silver dressing [147]. The antioxidant test showed that ethanolic turmeric extract had better antioxidant activity than oregano, chitosan nanoparticles, and alginate silver (\(p\) value \(<\) 0.0001). Thus, the bioassay result showed that the ointment, hydrogel, and commercial alginate silver produced 100% inhibition against _S. aureus_ and _E. coli_, and nanofibers produced 50% inhibition [148]. In another study, [PERSON] et al. formulated thyme or oregano essential oils into the \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{1}{c}{**Essential Oils**} & \multicolumn{1}{c}{**Wound Dressing System**} & \multicolumn{1}{c}{**Method**} & \multicolumn{1}{c}{**Bioassay**} & \multicolumn{1}{c}{**References**} \\ \hline \multirow{4}{*}{Cinnamaldehyde} & Chitosan fibers & Centrifugal spinning & _Staphylococcus aureus_ & [130] \\ \cline{2-5}  & Chitosan/polyethylene & \multirow{2}{*}{Electrospipinning} & _Escherichia coli_ and & \multirow{2}{*}{[131]} \\  &oxide & & _Pseudomonas aeruginosa_. & \\ \hline \multirow{3}{*}{Clove and Sandalwood oils (_Syzygium aromaticum_ and _Santium_)} & Dextran/ & \multirow{3}{*}{Nanoprecipitation/casting} & _S. aureus_ and _E. coli_ & [132] \\  & nationoscopy & & & \\ \cline{1-1}  & chitosan nanocomposite membranes & & & \\ \hline \multirow{3}{*}{Eugenol oil (Clove oil- _Syzygium aromaticum_)} & Polycaprolactone/polyvinyl & \multirow{3}{*}{Emulsion electrospinningning} & _Staphylococcus aureus_ and & [133] \\  & alcohol/chitosan fiber & & & _Pseudomonas aeruginosa_ & [134] \\ \hline \multirow{4}{*}{Thyme oil (_Zaturia multifora_)} & Chitosan poly(vinyl & \multirow{3}{*}{Electrospinning} & _Staphylococcus aureus_, & \multirow{3}{*}{[134]} \\  & alcohol/gelatin & & & _Candidia albicans_ & \\ \cline{1-1}  & nationofibers & & & \\ \cline{1-1}  & chitosan/poly(vinyl & \multirow{3}{*}{Electrospinning} & _Staphylococcus aureus_, & \multirow{3}{*}{[134]} \\  & alcohol)/gelatin. into poly & & & _Pseudomonas aeruginosa_ and & \\ \cline{1-1}  & (vinyl alcohol) nanofibers & & & \\ \hline \multirow{4}{*}{Terpinen-4-ol (from _Malaleuca alternifolia_} & Liposomes-incorporated & \multirow{3}{*}{Thin-film hydration and _Escherichia coli_, & \multirow{3}{*}{[135]} \\  & chitosan/polyethylene & & & \\ \cline{1-1}  &oside electrospun & & & \\ \cline{1-1}  & nanofibrous film & & & \\ \hline \multirow{4}{*}{_Satureja mutica_ or _Oliveria accumbens_ essential oil & Chitosan/polyvinyl & \multirow{3}{*}{Electrospinning} & _E. coli_, _S. aureus_, and & \multirow{3}{*}{[136]} \\  & alcohol as core and & & & \\ \cline{1-1}  & polyvinylpyrrolidone & & & _P. Aeruginosa_ and & \\ \cline{1-1}  & done/malodextrin & & & antioxidant activity & \\ \hline \multirow{4}{*}{_Zataria multifora_ essential oil & chitosan/poly(vinyl & \multirow{3}{*}{Electrospinning} & _Staphylococcus aureus_, & \multirow{3}{*}{[137]} \\  & alcohol)/gelatin & & & \\ \hline \hline \end{tabular}
\end{table}