Silk fibroin nanofibers loaded with hydroxytyrosol from hydrolysis of oleuropein in olive leaf extract

Abstract

The purpose of this study was to prepare antimicrobial silk fibroin nanofibers from the aqueous formic acid solutions of silk fibroin and hydroxytyrosol with the in situ hydrolysis of oleouropein present in olive leaf extract using electrospinning method. With the use of aqueous formic acid solution of olive leaf extract and silk fibroin resulted in more uniform and beadless nanofibers. Morphological properties of electrospun nanofibers were investigated using Scanning Electron Microscope (SEM). The diameter of electrospun nanofibers ranged between 70 nm to 150 nm. The nanofiber diameter did not changed much with increasing concentration of olive leaf extract added into silk fibroin solution to be used in electrospinning process. The increase in olive leaf extract concentration resulted in beadless and uniform nanofiber structures. The average diameter of the nanofibers prepared with fibroin solution having 10 % olive leaf extract was determined as 85 ± 10 nm. Results revealing the formation of smoother and uniform nanofibers was attributed to the crosslinking effect of oleuropein and polyphenols present in olive leaf extract with certain functional groups in silk fibroin structure. Antibacterial properties of hydroxytyrosol loaded nanofibers against Staphylococcus epidermidis (Gram +) and Escherichia coli (Gram-) were confirmed with the clear inhibition zones observed in disc diffusion tests. Silk Fibroin nanofibers loaded with hydroxytyrosol may offer a new alternative biomaterial to be used in wound dressing or medical textile applications.

Double-Layer Membranes of Chitosan and Sodium Alginate Added to Natural Olive Leaf Extract for Potential Use in Skin Lesions

“…However, the pure membranes (CS/SA) did not show an inhibition zone for either of the two strains studied (Escherichia coli and Staphylococcus aureus). Bayraktar [61] also observed the absence of inhibition in his silk fibroin nanofibers without olive leaf extract for the studied species (Staphylococcus epidermidis and Escherichia coli) in his work. Similarly, Avila et al [38] verified inhibition halos of 8.77 ± 0.31 mm for E. coli and 9.32 ± 0.21 mm for S. aureus in chitosan and zein fiber bilayer films with added jaboticaba peel extract, whereas the films without extract showed no inhibition against the microorganisms evaluated.…”

Controlled-Release Wedelia trilobata L. Flower Extract Loaded Fibroin Microparticles as Potential Anti-Aging Preparations for Cosmetic Trade Commercialization

“…One potential approach is the encapsulation of WT flower extract in a biomaterial-based drug delivery system that is both safe for humans, effective in protection against external influences, and controlled releases of active ingredients. 21 To this end, microparticles fabricated from silk fibroin are an interesting system. Fibroin, a protein commonly extracted from Bombyx mori silk, possesses favorable properties of high stability, non-toxicity, high biocompatibility, and biodegradability.…”

“…29,30 Nevertheless, most studies focus on only one pure antioxidant such as curcumin, 31,32 resveratrol, 33 and quercetin. 34 To the best of our knowledge, limited studies have explored the potentials of FMPs in delivering plant extracts, 21,28 and no report has mentioned about the application of FMPs for anti-aging purpose.…”

New Nanofibers Based on Protein By-Products with Bioactive Potential for Tissue Engineering

“…The main advantage of electrospun fibers is the greater surface area to volume ratios of 1-3 orders of magnitude larger than thin films made of the same material [4], which allows increased contact with skin, sensing analyte, and pollutant substance, or for other applications. Nanofibers based on ethylene-co-vinyl alcohol (EVOH) [5], xanthan polysaccharide [6], silk fibroin [7], chitosan/poly(ethylene oxide) [8], poly(ethylene oxide) (PEO), and poly(vinyl alcohol) (PVA) [9] have been achieved by electrospinning. Although synthetic polymers show good rheological and mechanical properties, their biocompatibility has some limitations and can produce inflammation [10].…”