Review on application of herbal extracts in biomacromolecules-based nanofibers as wound dressings and skin tissue engineering

The skin, which covers an area of 2 square meters of an adult human, accounts for about 15 % of the total body weight and is the body's largest organ. It protects internal organs from external physical, chemical, and biological attacks, prevents excess water loss from the body, and plays a role in thermoregulation. The skin is constantly exposed to various damages so that wounds can be acute or chronic. Although wound healing includes hemostasis, inflammatory, proliferation, and remodeling, chronic wounds face different treatment problems due to the prolonged inflammatory phase. Herbal extracts such as Nigella Sativa, curcumin, chamomile, neem, nettle, etc., with varying properties, including antibacterial, antioxidant, anti-inflammatory, antifungal, and anticancer, are used for wound healing. Due to their instability, herbal extracts are loaded in wound dressings to facilitate skin wounds. To promote skin wounds, skin tissue engineering was developed using polymers, bioactive molecules, and biomaterials in wound dressing. Conventional wound dressings, such as bandages, gauzes, and films, can't efficiently respond to wound healing. Adhesion to the wounds can worsen the wound conditions, increase inflammation, and cause pain while removing the scars. Ideal wound dressings have good biocompatibility, moisture retention, appropriate mechanical properties, and non-adherent and proper exudate management. Therefore, by electrospinning for wound healing applications, natural and synthesis polymers are utilized to fabricate nanofibers with high porosity, high surface area, and suitable mechanical and physical properties. This review explains the application of different herbal extracts with different chemical structures in nanofibrous webs used for wound care.