Bioactive Sheath/Core nanofibers containing olive leaf extract

Abstract

This study aimed at producing silk fibroin (SF)/hyaluronic acid (HA) and olive leaf extract (OLE) nanofibers with sheath/core morphology by coaxial electrospinning method, determining their antimicrobial properties, and examining release profiles of OLE from these coaxial nanofibers. Optimum electrospinning process and solution parameters were determined to obtain uniform and bead-free coaxial nanofibers. Scanning electron microscopy and transmission electron microscopy (TEM) were used to characterize the morphology of the nanofibers. The antimicrobial activities of nanofibers were tested according to AATCC test method 100. Total phenolic content and total antioxidant activity were tested using in vitro batch release system. The quality and quantity of released components of OLE were determined by high-performance liquid chromatography. The changes in nanofibers were examined by Fourier-transform infrared spectroscopy. Uniform and bead-free nanofibers were produced successfully. TEM images confirmed the coaxial structure. OLE-loaded nanofibers demonstrated almost perfect antibacterial activities against both of gram-negative and gram-positive bacteria. Antifungal activity against C. albicans was rather poor. After a release period of 1 month, it was observed that $70-95% of the OLE was released from nanofibers and it was still bioactive. Overall results indicate that the resultant shell/core nanofibers have a great potential to be used as biomaterials. Microsc.

Encapsulation of fish oil in a coaxial electrospun nanofibrous mat and its properties

“…12 It was reported that olive leaf extract was successfully encapsulated into coaxial silk broin/hyaluronic acid nano-bers, which exhibited favourable antibacterial properties and release stability. 13 Lópezrubio et al found that coaxial electrospinning was a more efficient method to entrap living bidobacteria cells and improve their viability compared with single electrospinning. 14 Zein is the major storage protein of corn, and has extensive application in encapsulation of bioactive substances.…”

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

“…The hydrolysis of oleuropein into hydroxytrosol and its derivatives helped the enhancement of the antibacterial activity of the olive leave extract having oleuropein as main constituent. Antimicrobial activity of oleuropein and hydroxytyrosol were also reported in the literature[23,24]. Hydroxytyrosol has higher antimicrobial activity compared with that of oleuropein.…”

Adsorption/desorption and biofunctional properties of oleuropein loaded on different types of silk fibroin matrices

“…Among these techniques, electrospinning is usually preferred as it allows versatility in the control of the size of nanofibers, convenience for scaleup, and flexibility in terms of the materials used for nanofiber production [5]. Different biopolymers, such as collagen, silk fibroin, hyaluronic acid, and zein can be used to prepare nanofibers by electrospinning [2,6,7]. The silk fibroin used in this study is an important natural biopolymer and has been used to prepare electro-spun nanofibers that are used in many biotechnological applications such as in medical textiles, drug delivery and tissue scaffolding [8].…”

“…However, less toxic, naturally occurring antimicrobial agents are still needed for biotechnological applications. Recently, nanofibers incorporating bioactive natural compounds have received much attention for biomedical and tissue engineering applications [5,6]. There is intense interest in the use of plant-derived natural compounds having different bioactivities for many biotechnological applications [18].…”

“…However, natural compounds have a tendency to lose their stability along with their bioactivities due to interactions with other components in blend solutions and under harsh conditions. Instead of directly mixing natural compounds into polymer solutions for electrospinning, it would be better to either prepare coaxial nanofibers encapsulating natural compounds in the core region [6], or to adsorb the natural compounds selectively on the surface of prepared nanofibers to avoid stability problems [5].…”