## 4 Discussion
All the recorded peaks were identical with the reported EPS levan and showed that the purified levan is \(\beta\)-(2\(\rightarrow\)6)-linked fruct [17; 37]. In accordance with previous recorded information from \({}^{13}\)C NMR studies [10], six signals in the range of 60-110 ppm range were characteristic of ideal polysaccharide spectra. The chemical shift signals of 104.18 (C-2) and 63.37 ppm (C-6) are due to the presence of \(\beta\)-(2\(\rightarrow\)6)-linked fruct [27]. Researchers and industries have been interested in microbial polysaccharides because of their non-toxic and biodegradable nature as well as their wide range of features that make them suitable for a variety of applications [38]. Commercial production and many industrial uses have sparked a lot of interest in levan due to its applications as a sweetener, gum, stabilizer, emulsifier,encapsulating agent, thickener, and an appropriate raw material for the manufacturing of green plastics. [31]. Many applications of levan have been documented in relation to its unique properties when compared to other polysaccharides. In our study, antibacterial, antibiofilm-forming, and burn healing properties of the produced levan were determined. Our results of levan as an antibiofilm-forming agent agreed with [37], which mentioned that the reduction of biofilm formation was related to increasing the concentration of levan. Additionally, they reported that the bactericidal effect of EPS is not responsible for the biofilm formation inhibition. It could be due to the inhibition of the attachment mechanism in the early stages of bacterial development as well as to changes to the cell surface that reduce auto-aggregation and bacterial cell interaction. Burns are traumatic injuries that cause the skin to be destroyed or broken. Burn injuries are associated with a high morbidity and mortality rate [39]. A burn becomes healed when a new epithelium forms over the injury, as evidenced by visual examination [40]. Synthetic drugs used to treat burn injuries are currently limited due to their high cost and potential side effects, such as allergy or drug resistance [41]. As a result, these problems must be solved by developing a therapy that promotes wound healing while simultaneously addressing therapeutic needs. Previous skin substitutes relied on naturally occurring components in the wound that could be stimulated during the healing process. Inflammation, proliferation, and modification of the extracellular matrix in the skin are the three stages of wound healing. Angiogenesis, collagen deposition, epithelialization, and wound contraction are among the events that occur during the proliferative phase [39]. Polysaccharides derived from plants have shown to have amazing impacts on human skin cells [42]. The significant increases in proliferation rates and cell viability in human or animal skin fibroblasts and keratinocytes suggest that various carbohydrates have a beneficial influence on skin regeneration [42]. Additionally, plant polysaccharides activate polymorphonuclear cells, the complement system, fibroblasts, and vascular endothelial cells during the inflammatory phase [43]. In the current research, levan accelerated the process of the healing of the burn area, which could be attributed to the ability of levan to activate matrix metalloproteinase (MMPs) enzymes. These enzymes are necessary for the degradation of collagen, a very important step in tissue repair [44]. Metalloproteinases play a vital role in the healing of burned or mechanically damaged tissues [45]. Furthermore, levan showed relatively weak antibacterial activity, and its ability to activate MMPs is very important in preventing wound and burn infection [46]. The antibacterial activity may help to accelerate the healing process. However, a variety of events and conditions can potentially interfere wound healing. The colonization of the wound bed by microorganisms is one issue that delays the progression of the wound healing effect [40].