Mycelial Mattress from a Sporangia Formation-Delayed Mutant of Rhizopus stolonifer as Wound Healing-Enhancing Biomaterial

Abstract

A mycelial mattress of Rhizopus stolonifer obtained from a liquid static culture was utilized for wound dressing and biomedical use. Following screening of mutants induced by UV radiation, F6, exhibiting delayed sporangium formation was selected because its sporangium maturation exhibited a 5-day delay without significant loss of mycelial weight compared to the wild type. The sporangium-free mycelial mattress from the sporangiospore culture of F6 was treated with 1N sodium hydroxide at 85°C for 2 h to produce a sponge-like membrane named Rhizochitin. The trifluoroacetic acid hydrolysate of Rhizochitin contained 36% N-acetylglucosamine and 53% hexose respectively detected by the Elson-Morgen and phenol-sulfuric acid methods. Results indicated the wound area in rats covered with Rhizochitin was 40% less than that of the uncovered group. Rhizochitin decreased the expression of PDGF in the proliferation stage, increased the expression of TGF-β in the inflammation and proliferation stages, and increased the expression of VEGF in the inflammation and proliferation stages. Rhizochitin inhibited secretion of matrix metalloproteinase-9 on days 1, 7, 9, and 12 and matrix metalloproteinase-2 on days 3, 7, 9, and 12. It was concluded that Rhizochitin has beneficial properties of biocompatible, biodegradable, and wound healing.

Fungal exopolysaccharides: Properties, sources, modifications, and biomedical applications

“…The in vivo studies also confirmed the wound healing efficacy of the mycelial mattress (Fig. 5) (Chien et al, 2015) indicated by the epidermal layer formation and resemblance of the healed wound to normal skin.…”

“…Additionally, as P. blakesleeanus sample, which had the highest chitin content (91%), showed better proliferation activity than that of A. oryzae with a chitin content of 37%, indicating that the proliferative impact could be associated with their chitin quantity (Chung et al, 1994). Also, Mei-Yin Chien et al showed that a chitin-containing mycelial mattress of Rhizopus stolonifera (called Rhizochitin) can be used for wound dressing (Chien et al, 2015).…”

Advanced mycelium materials as potential self-growing biomedical scaffolds

“…Examples are the Saccachitin reported by Su and colleagues and the Rhizochitin produced by Chien et al . , where the chitin extracted from mycelia is casted in membranes tested as skin substitute and for the growth of fibroblasts 49 , 50 or for its immunomodulatory activity 93 .…”

“…Membranes produced by simply casting these extracts, such as the Saccachitin reported by Su et al 49 and the Rhizochitin produced by Chien et al . 50 , showed positive effects on fibroblast and keratinocytes growth. As far as we know, only the work by Narayanan et al .…”

From Nature to Design: Tailoring Pure Mycelial Materials for the Needs of Tomorrow

“…Another process included the mycelium isolation of a non-dikaryotic species called Rhizopus stolonifera . The sporangia-producing mucoromycete was studied for the creation of a thick “mycelium mattress” that was deproteinized and dried for wound healing purposes [ 2 , 111 ].…”