Polyacrylonitrile (PAN) nanofiber mats for mushroom mycelium growth investigations and formation of mycelium-reinforced nanocomposites

Abstract

Mycelium-bound composites are new environmentally friendly, cost-effective and sustainable materials, enable energy-saving bio-composite fabrication, and provide an alternative to synthetic materials. Current research on mycelium-based composites reports on relatively coarse material compositions such as rice husks, cotton residues, sawdust, leaves and bio-waste, etc. According to research, very few publications report on mycelium-reinforced composites with the use of nanomaterials and this topic is under-researched and this study helps to fill this gap. The focus of this study deals with the preparation of mycelium-reinforced nanocomposites including nanofiber mats and the investigation of the different nanofiber mat morphologies on the growth of fungal mycelium. The mycelium macrofibers from Pleurotus ostreatus fungi were grown on polyacrylonitrile (PAN) nanofiber mats. Different morphologies of nanofiber mats such as fibrous and non-fibrous membrane areas or a mixture of both were used for mycelial growth with an additional nutrient. Moreover, mycelium/PAN nanocomposites were oxidative stabilized and carbonized and mycelium retains its morphology. For faster color differentiation between mycelium and nanofibers, PAN nanofiber mats were dyed in a one-step process by adding dye powder to the electrospinning solution as an additional tool. No significant differences in mycelial growth and morphology were observed regarding the different nanofiber mat types and the use of dye. These mycelium-reinforced nanocomposites are promising for many applications such as medicine and biotechnology, air and water purification and filtration, vertical farming, architecture, etc., and enable energy-saving bio-composite fabrication.

Current situation and future perspectives for the use of fungi in the biomaterial industry and proposal for a new classification of fungal-derived materials

“…As with mycocomposites, hybrid mycelium materials are compounds based on fungal mycelium (Table S4), with the difference that the latter can be added with organic and inorganic compounds (Attias, 2020;Trabelsi et al, 2021;Elsacker et al, 2021;Elsacker, De Laet & Peeters, 2022). The role of additives in the composition of these hybrids arises as a response to the need to improve the mechanical behavior of mycocomposites in natura (only mycelium and substrate).…”

“…Among the additives described are cellulose derivatives, whether microfibrils or cellulosic nanomaterials, the latter include cellulose nanocrystals (CNC), cellulose nanofibrils (CNF), and bacterial nanocellulose (NCB). Other additives are carbon nanotubes (CNT), polyacrylonitrile nanofibers (PAN), montmorillonite nanoclay, ground Full-size  DOI: 10.7717/peerj-matsci.31/fig- 7 glass, and latex, among others (Nawawi et al, 2020a;Trabelsi et al, 2021;Sayfutdinova et al, 2022;Elsacker, De Laet & Peeters, 2022). Of special attention is the need for separation between compositions of coarse materials, a term used for compounds of agricultural residues or biowaste linked to the mycelium, and compositions with refined or sensitive materials, a term used when nanomaterials are part of the composition.…”

“…Of special attention is the need for separation between compositions of coarse materials, a term used for compounds of agricultural residues or biowaste linked to the mycelium, and compositions with refined or sensitive materials, a term used when nanomaterials are part of the composition. The exploitation of the latter for the production of materials derived from mycelium is more recent and has a smaller number of publications, and this nanobiotechnology is considered promising for the future (El Naschie, 2006;Trabelsi et al, 2021).…”

“…The growth of nanofiber mats associated with biological structures may be suitable to increase the mechanical stability of the product compared to the pure nanofiber mat. In this case, the mycelium confers good mechanical properties (Sabantina et al, 2019;Trabelsi et al, 2021). In the aforementioned studies, the polyacrylonitrile nanofiber mat was adopted, a synthetic acrylic polymer widely used in the manufacture of rugs, carpets, furniture upholstery, and clothes, since PAN is petroleum-derived and non-biodegradable.…”

“…In conclusion, heavy metals sorption was observed in the mycomaterial, when compared to the hybrid nanocomposite-mycelium without the fungal growth. Thus, hybrid nanocomposite-mycelium materials are promising for the fields of biotechnology in medicine, agriculture, environment, architecture, food packaging, and textile industry, among others (Sun et al, 2019;Sabantina et al, 2019;Irbe et al, 2021;Trabelsi et al, 2021).…”