INTRODUCTION: Sustainable bio-based materials are essential for addressing the environmental challenges associated with petroleum-derived products. Filamentous fungi, often described as nature’s recyclers, possess a remarkable ability to decompose organic waste and return valuable nutrients to the environment. During growth, filamentous fungi form microfibrillar networks known as mycelium. Mycelium-based materials have attracted increasing attention across diverse application areas due to their renewability, low environmental impact, and tunable properties. Furthermore, the fungal cell wall contains biopolymers such as chitin and chitosan, which represent promising building blocks for the development of circular and sustainable materials, particularly in biomedical applications. This research explores the potential of food-waste-derived mycelium materials for use in biomedical applications.

 METHODS: Two fungal species belonging to the Ascomycota and Mucoromycota phyla were cultivated on food waste (bread residues) in bubble column bioreactors, and the process was subsequently scaled up. The harvested biomass was subjected to alkaline treatment to isolate fungal cell wall materials containing chitin– glucan (Ascomycota) and chitin–chitosan (Mucoromycota), respectively. Aerogels were fabricated from the extracted cell wall materials via acid-assisted gelation, followed by freezing and freeze-drying. The resulting aerogels were evaluated for cytotoxicity toward fibroblasts at different concentrations using a leachate-based MTT assay. Antibacterial activity was assessed against both Gram-positive and Gram-negative bacteria. 

RESULTS: Both fungal strains were successfully cultivated under submerged conditions, resulting in well-dispersed fungal biomass. Alkali-insoluble fractions corresponding to fungal cell wall materials were efficiently recovered and subsequently used for aerogel fabrication. Cytotoxicity assessment revealed greater than 80% cell viability relative to the control when fibroblasts were exposed to aerogel leachates at concentrations up to 2500 μg/mL for 48 h. Furthermore, the addition of aerogels at this concentration to Müller–Hinton broth significantly inhibited the growth of Escherichia coli (Gram-negative) and Bacillus megaterium (Gram-positive). Figure 1: Food waste derived mycelium-based aerogels for biomedical applications 

DISCUSSION & CONCLUSIONS: Aerogels were successfully fabricated from fungal cell wall materials derived from food-waste-grown fungal biomass. The resulting aerogels exhibited good biocompatibility and antibacterial activity, highlighting their potential as renewable and circular biomaterials for biomedical applications.

Stereolithography (SLA) and digital light processing (DLP) are rapidly expanding UV-curing additive manufacturing (AM) technologies, recognized for their high resolution and processing speed. In parallel, itaconic acid–based resins have emerged as promising UV-curable formulations, offering high renewable content, compatibility with established diluents, and structural versatility through facile molecular modification. Despite these advantages, the end-of-life strategies remain insufficiently investigated, hindering integration into sustainable manufacturing frameworks. Here, we present 3D-printable disulfide-based covalent adaptable networks (CANs) derived from itaconic acid. The synthesized unsaturated polyester resins were readily formulated with multiple commercial diluents. The resulting systems were evaluated with respect to printability and thermomechanical performance, resulting in 3D printed materials with a glass transition temperature range between 53 and 76 °C and elongation at break between 93 and 142%. The recyclability of the manufactured parts was evaluated through three consecutive cycles of thermal reprocessing or grinding to be utilized as component in new resin formulations. Our findings highlight the potential of disulfide-containing itaconate networks as a versatile platform for next-generation light processable AM resins. 

Growing environmental concerns associated with synthetic materials have intensified the demand for sustainable alternatives derived from renewable sources. In addition, the increasing global population has led to a surge in the demand for food products including juice, resulting in the generation of substantial quantities of byproducts, which are organic waste with the potential for valorization. This study investigated the bioconversion of carrot pomace (CP), waste generated in the juice industry, into fungal biomass to produce mycelium-based foams. Filamentous fungus (Aspergillus oryzae) was cultivated on carrot pomace through a submerged process in a bubble column bioreactor. The analysis of the scanning electron microscopy (SEM) confirmed the presence of the fungal mycelium and CP residues in the material recovered from the bioreactor. This material was mixed with water, and the suspension was subjected to different grinding cycles in an ultrafine grinder, and mycelium-based foams were then formed via freeze-molding and freeze-drying. The resulting foams exhibited an average density of 21.1 kg/m3, with compressive resistance values of 5.8 kPa at 10% deformation and 20.5 kPa at 30% deformation. These mechanical properties are comparable to those of commercial lightweight foams, as indicated by the Ashby material plot. These findings demonstrate the potential of mycelium-based foams as an alternative to synthetic materials, contributing to waste valorization and development of environmentally friendly materials.

Food-waste-derived bio-based materials offer both environmental and economic advantages. We utilised waste lemon peel as substrate to generate value-added materials from chitosan-rich fungal cell wall of Rhizopus delemar and purified cellulose from pre-treated solid residues. Nutrient from lemon peel was used for fungal cultivation and the cell wall was isolated from the obtained fungal biomass using mild alkali treatment. The fungal cell wall was used to develop a hydrogel through protonation of amino groups in chitosan by lactic acid addition. This hydrogel served as spinning dope to produce fungal monofilaments using dry gel spinning with a tensile strength of 85 MPa. Simultaneously, cellulose purified from pre-treated solid residues, converted to micro-nanocellulose suspension via mechanical fibrillation and underwent dry gel spinning to produce cellulose monofilaments with a tensile strength of 298 MPa. Cellulose fraction was analysed using XRD, FTIR, TGA, and elemental analyses. The micro- and nanoscale structures of fibrillated cellulose were verified by SEM and AFM. The findings of this study demonstrate a novel holistic valorisation approach for lemon peel waste as a resource for bio-based monofilaments, which could be used as alternatives to commercial fibres in textiles.

Despite being considered a premium material, leather poses both environmental and ethical issues. Thus, sustainable alternatives such as vegan leather are in high demand. Therefore, in this study, we aimed to produce vegan leather using vegetable tannins and fungi grown on bread waste. Fungal cultivation was carried out in a bubble column bioreactor using nutrients extracted from bread as substrate. To obtain tanned biomass, the biomass was subjected to vegetable tanning (using Tara, Myrobalan, Chestnut, and Indusol ATO tannins). A mild alkali treatment isolated the fibrous cell wall material from fungal biomass. Different composite sheets were prepared by wet-laying the tanned biomass and cell wall material and placing them in a multilayer arrangement. The composites were post-treated with glycerol and a bio-based binder to improve their mechanical properties. Myrobalan-tanned biomass composites after glycerol and bio-based binder post-treatments had the highest flexibility of 14.8% elongation at break, and Tara-tanned biomass composites had the highest tensile strength of 20.5 MPa. Ashby’s chart demonstrates the relationship between the sheets produced and natural leather. SEM was used to demonstrate the softer and smoother morphologies of the Chestnut and Indusol ATO-tanned composite sheets after post-treatment. Overall, this study presents multilayer fungal biocomposites as a promising vegan alternative leather.

Protein extraction from wheat bran is challenging due to its multi-layer and fiber-rich structure. Here, opening aleurone cells, via dry and wet milling, their combination and a novel ultrafine milling, and its effect on wheat bran's protein recovery using the alkaline solubilization/isoelectric precipitation and protein structure, functionality, and phytate content were investigated. Wet milling and ultrafine milling improved protein recovery and purity but only ultrafine milling reduced bran particle size to the aleurone cells and exposed their structure. Despite this, ultrafine milling did not significantly increase protein yield compared to wet milling, which partially opened the aleurone cells, meaning that opening the cells per se is not enough for extracting their protein. Proteins extracted with the aid of ultrafine milling had smaller particle sizes with significantly better water solubility (>2-fold) and rheological properties. Both wet milling and ultrafine milling significantly improved the removal of phytate during the wet fractionation process. Altogether, optimizing milling techniques offers a promising path to enhance accessibility to wheat bran proteins and their quality if carefully fine-tuned but other assistant technologies are necessary for boosting the recovery of the released protein from aleurone cells.

Fungal mycelium is emerging as a source for sustainable bio-based materials. Fungal biomass of Aspergillus oryzae was prepared by cultivation on bread waste hydrolysate to valorize this abundant food waste. Chitin-glucan-rich alkali-insoluble material (AIM) was isolated from fungal biomass, formed into hydrogels, and wet spun into monofilaments. AIM in the form of fungal microfibers containing 0.09 g polymer of glucosamine (GlcN)/g AIM was subjected to freeze–thaw and deacetylation treatments to increase the amount of GlcN. The GlcN fraction was 0.19 and 0.34 g polymer of GlcN/g AIM, for AIM subjected to deacetylation (AIM-DAC) and freeze–thaw cycles and deacetylation (AIM-FRTH-DAC), respectively. The increased GlcN fraction enabled the formation of hydrogels via the protonation of amino groups after the addition of lactic acid. Morphological differences in the hydrogels included aggregation of the fungal microfibers in the AIM-DAC hydrogel, whereas the microfibers in the AIM-FRTH-DAC hydrogel had a porous and interconnected network. Rheological assessment revealed shear thinning behavior and gel properties of the produced hydrogels. Wet spinning of the hydrogels resulted in monofilaments with tensile strengths of up to 70 MPa and 12 % elongation at break. This demonstrates promising avenues for biomaterial development from fungal cell walls containing chitin-glucan via food waste valorization.

Background: Renewable materials made using environmentally friendly processes are in high demand as a solution to reduce the pollution created by the fashion industry. In recent years, there has been a growing trend in research on renewable materials focused on bio-based materials derived from fungi. Results: Recently, fungal cell wall material of a chitosan producing fungus has been wet spun to monofilaments. This paper presents a modification for the fungal monofilament spinning process, by the development of a benign method, dry gel spinning, to produce continuous monofilaments and twisted multifilament yarns, from fungal cell wall, that can be used in textile applications. The fungal biomass of Rhizopus delemar, grown using bread waste as a substrate, was subjected to alkali treatment with a dilute sodium hydroxide solution to isolate alkali-insoluble material (AIM), which mainly consists of the fungal cell wall. The treatment of AIM with dilute lactic acid resulted in hydrogel formation. The morphology of the hydrogels was pH dependent, and they exhibited shear thinning viscoelastic behavior. Dry gel spinning of the fungal hydrogels was first conducted using a simple lab-scale syringe pump to inject the hydrogels through a needle to form a monofilament, which was directly placed on a rotating receiver and left to dry at room temperature. The resulting monofilament was used to make twisted multifilament yarns. The process was then improved by incorporating a heated chamber for the quicker drying of the monofilaments (at 30⁰C). Finally, the spinning process was scaled up using a twin-screw microcompounder instead of the syringe pump. The monofilaments were several meters long and reached a tensile strength of 63 MPa with a % elongation at break of 14. When spinning was performed in the heated chamber, the tensile strength increased to 80 MPa and further increased to 103 MPa when a micro-compounder was used for spinning. Conclusion: The developed dry gel spinning method shows promising results in scalability and demonstrates the potential for renewable material production using fungi. This novel approach produces materials with mechanical properties comparable to those of conventional textile fibers. 

Cheese whey is an industrial by-product that is generated in excess during the cheese production process in the dairy industry. Despite the potential utility of whey, it continues to pose environmental threats in the industry. This study comprehensively evaluates the utilization of two fermentation techniques (solid-state fermentation and submerged fermentation) for producing fungal biomass from cheese whey powder, employing Aspergillus oryzae, Rhizopus oryzae, and Neurospora intermedia for sustainable food production. It has been observed that submerged fermentation is more effective in increasing the protein content of whey powder compared to solid-state fermentation. The highest biomass yield was achieved with A. oryzae (5.29 g/L, 0.176 g biomass/g substrate), followed by N. intermedia (3.63 g/L, 0.121 g biomass/g substrate), and R. oryzae (1.9 g/L, 0.063 g biomass/g substrate). In the bubble column reactor, the protein content of the substrate (78.65 g/kg) increased by 165.54 and 176.69% with A. oryzae (208.85 g/kg) and N. intermedia (217.62 g/kg), respectively. This study has demonstrated that whey powder can be converted into protein-rich biomass through fungal bioconversion. The obtained biomass has the potential to be developed as an alternative food and feed source, contributing to waste management and sustainable food production. 

A fungal biorefinery is presented to valorize food waste to fungal monofilaments with tunable properties for different textile applications. Rhizopus delemar is successfully grown on bread waste and the fibrous cell wall is isolated. A spinnable hydrogel is produced from cell wall by protonation of amino groups of chitosan followed by homogenization and concentration. Fungal hydrogel is wet spun to form fungal monofilaments which underwent post-treatments to tune the properties. The highest tensile strength of untreated monofilaments is 65 MPa (and 4% elongation at break). The overall highest tensile strength of 140.9 MPa, is achieved by water post-treatment. Moreover, post-treatment with 3% glycerol resulted in the highest elongation % at break, i.e., 14%. The uniformity of the monofilaments also increased after the post-treatments. The obtained monofilaments are compared with commercial fibers using Ashby's plots and potential applications are discussed. The wet spun monofilaments are located in the category of natural fibers in Ashby's plots. After water and glycerol treatments, the properties shifted toward metals and elastomers, respectively. The compatibility of the monofilaments with human skin cells is supported by a biocompatibility assay. These findings demonstrate fungal monofilaments with tunable properties fitting a wide range of sustainable textiles applications.