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In this study, the possibility of microencapsulation of Oliveria decumbens essential oil (ODEO) was investigated on the microstructure of microfibers. The fibers were produced using polymeric cellulose acetate (CA) and the essential oil was added to the electrospun solution at different concentrations (0, 15, 25, 35 and 45%). The samples were analyzed using SEM and FTIR. SEM micrographs showed that all of fibers had homogenous structure without nodes. However addition of ODEO at 45% significantly increased the diameter of fibers compared to control sample. FTIR results of control and 45% ODEO fibers showed that in both samples there are distinct peaks of CA, and in fiber containing essential oils in addition to the CA peaks, the peaks in the 812 belong to the compound containing para and in 771 and 899 are related to compounds containing meta bonds. Both of them represent the aromatic compounds of the essential oil. The results of the antimicrobial activity of the fibers showed that the inhibition of the ODEO fibers against Staphylococcus aureus was generally higher than E. coli. Antimicrobial activity was increased with increasing ODEO concentrations.

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The mixture of cellulose acetate (CA), and poly (ethylene oxide) was electrospun into Nanofibrous webs using an acetic acid solution. The impact of cellulose acetate (CA)/ polyethylene oxide (PEO) ratio (1, 1.5, 2 wt %), sodium dodecyl sulfate (SDS) (0, 1.5, 3%, w/w) and ammonium oxalate (3%, w/w) on the diameter, tensile strength, elongation and porosity (PO) of the Electrospun Nano-fibers (ENFs) were enhanced applying response surface methodology-central composite rotatable design (RSM-CCRD). The ENFs were formed of non-woven fibers with a maximum diameter of 163 nm. Second-order polynomial models with high R² values (0.86–0.97) were developed using Cubic analysis. The outcome revealed that the ENFs morphology and diameter were noticeably affected by CA, PEO, and SDS. The overall optimum condition was identified to be at the compounded level of CA to PEO ratio of 2 wt % and SDS content of 3% (w/v). At the best point, diameter, surface tension, elongation, and porosity of the fabricated electrospun nanofibers (ENFs) were 99 nm, 0.017 N/mm², 5 mm and 17.54 respectively. The most fabricated ENFs were uniform and bead-free with high active sites and mechanical strength, which could be used in different fields.