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Effect of particle size on mechanical properties of mycelium composites: a stress–stretch curves, and b the dependence of the loading modulus (Ec\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ E_{\text{c}} $$\end{document}) and c unloading modulus (Ecu\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ E_{\text{c}}^{\text{u}} $$\end{document}) on filler size. The error bars represent the range of four test samples

Effect of particle size on mechanical properties of mycelium composites: a stress–stretch curves, and b the dependence of the loading modulus (Ec\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ E_{\text{c}} $$\end{document}) and c unloading modulus (Ecu\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ E_{\text{c}}^{\text{u}} $$\end{document}) on filler size. The error bars represent the range of four test samples

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This work investigates the mechanical behavior of mycelium composites reinforced with biodegradable agro-waste particles. In the composite, the mycelium acts as a supportive matrix which binds reinforcing particles within its filamentous network structure. The compressive behavior of mycelium composites is investigated using an integrated experimen...

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... After incubation, the composites were oven-dried at 40°C for 72 hours, but as fungal growth was not yet fully terminated, an additional heat treatment of 100°C for 2 hours was conducted. Hence, expanding the investigated temperature range is crucial to fully comprehend the behaviour of mycelium composites, particularly in terms of terminating mycelium growth, rendering the material biologically inactive and achieving desired material properties (Islam et al., 2018). ...
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Mycelium, a root-like fungi network, possesses distinctive characteristics that render it an appealing contender for replacing polystyrene (PS). Drying in the oven is one of the most commonly used methods for producing mycelium composites. However, achieving its desired properties requires proper control of the drying temperature. This research aims to develop a mycelium-based composite by utilising an edible mushroom, specifically Pleurotus ostreatus (oyster mushroom), as an alternative to non-biodegradable materials for packaging applications. The composite is developed by inoculating Pleurotus ostreatus fungi into the substrate, mainly consisting of kenaf, wheat bran and CaCO3. Afterwards, the composite was incubated for 20 days and then subjected to drying at different oven temperatures (e.g. 40°C, 60°C, and 80°C) for 24 hours. Our findings indicate that the desirable mechanical properties of mycelium composite were found at 60°C, where flexural strength, flexural modulus and impact strength were obtained at 0.11 MPa, 4.15 GPa and 635.8 N, respectively. The moisture content was 26.13%, and the shrinkage was 20.73%. The obtained density of 0.15 g/cm3 was compared to the density of PS, which is 1.04 g/cm3. This research indicates that a lightweight composite material, consisting of a network of interconnected hyphae that function as a natural adhesive, holds significant potential as a viable solution for achieving a more sustainable and environmentally friendly future, primarily due to its biodegradability.
... The developed mycelium-based composites consist exclusively of biocompatible components, making them fully biodegradable and not a burden on the environment, similar to mycelium-based bioproducts studied by other authors [59,60]. Previous studies have indicated that after using mycelial biocomposites, they can be composted or re-used, for example as animal supplies, organic fertilisers, soil conditioners, and substrates for seedlings [4,61,62]. An important challenge in the technology of mycelial-based biomaterials is to simultaneously increase the durability of the composites during application while maintaining their biodegradable nature after application, which requires further research [63]. ...
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This study explores the potential use of mould biomass and waste fibres for the production of agrotextiles. First, 20 mould strains were screened for efficient mycelium growth, with optimized conditions of temperature, sources of carbon and nitrogen in the medium, and type of culture (submerged or surface). A method was developed for creating a biocomposite based on the mould mycelium, reinforced with commercial bleached softwood kraft (BSK) pulp and fibre additives (cotton, hemp). The best properties, including mechanical, water permeability, and air permeability, were shown by the biocomposites containing 10–20% Cladosporium cladosporioides mycelium grown in surface or submerged cultures, milled with BSK pulp, cotton, and hemp (10–20%). The mould mycelium was refined with cellulosic fibrous material, formed, pressed, and dried, resulting in a biomaterial with good mechanical parameters, low water permeability, and high air permeability. The biocomposite was fully biodegradable in soil after 10 days in field conditions. The use of the biocomposite as a crop cover shortened the germination time and increased the percentage of germinated onion, but had no effect on parsley seeds. This study shows the potential of using mould mycelium for the production of biomaterial with good properties for applications in horticulture.
... Still, only a few publications on mycelium composites tried to estimate this mass fraction so far. Jones et al. [55] and Islam et al. [56] based their quantification on ergosterol, which is only present in fungi, some algae, and protozoa [57]. The concentration was determined by high performance liquid chromatography and converted to fungal biomass via a linear relationship [55,56]. ...
... Jones et al. [55] and Islam et al. [56] based their quantification on ergosterol, which is only present in fungi, some algae, and protozoa [57]. The concentration was determined by high performance liquid chromatography and converted to fungal biomass via a linear relationship [55,56]. Islam et al. [56] presented their results in volume percent and did not distinguish between mycelium and pores, leading to a distribution of around 30 vol.% substrate and 70 vol.% ...
... The concentration was determined by high performance liquid chromatography and converted to fungal biomass via a linear relationship [55,56]. Islam et al. [56] presented their results in volume percent and did not distinguish between mycelium and pores, leading to a distribution of around 30 vol.% substrate and 70 vol.% mycelium (+ pores) for their composites of mycelium (fungal species not mentioned) and corn stover particles. ...
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Mycelium composite materials are comprised of renewable organic substrates interconnected by fungal mycelium, allowing full biodegradability after use. Due to their promising material properties, adaptability, and sustainable nature, these biomaterials are investigated intensively. However, one crucial aspect that has hardly been covered so far is the proportion of fungal biomass in the composites, which would be necessary to assess its contribution to the material characteristics. Since a complete physical separation of mycelium and substrate is not feasible, we approached this issue by isolating the fungal DNA and relating it to the mass of mycelium with the help of quantitative PCR. Overall, 20 different combinations of fungi and biogenic side streams were evaluated for their handling stability, and growth observations were related to the quantification results. Ganoderma sessile was able to form stable composites with almost all substrates, and a positive correlation between mycelial biomass and composite stability could be found. However, the amount of mycelium required for fabricating firm materials strongly depends on the combination of substrate and fungal species used. Less than five mass percent of fungal biomass can suffice to achieve this, as for example when combining Trametes versicolor with sugar beet pulp, whereas a mass fraction of twenty percent leads to crumbly materials when using Pleurotus pulmonarius on green waste. These results indicate that the mycelial biomass is an important factor for the composite’s stability but that the properties of the fungal hyphae, as well as those of the substrate, are also relevant. The presented quantification method not only allows to estimate fungal growth during composite production but can also improve our understanding of how the mycelium influences the material.
... The average density of the PP/sawdust was slightly higher than PO/sawdust composite. It was found that the density of mycelium composites in this study was within the density range of oyster mushroom mycelium/sawdust composite (100-270 kg/m 3 ) mentioned in several literatures (Islam et al., 2017(Islam et al., , 2018Elsacker et al., 2018;Appels et al., 2019;Elsacker et al., 2020). Generally, the density of a mycelium-based composite comes from the density of the mycelium that binds the particulate substrate together. ...
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Mycelium-based composite (MBC) offers an excellent sustainable alternative to hydrocarbon-based materials, especially styrofoam for packaging, due to its abundance of fungal mycelium that grows quickly on agricultural substrates, its biodegradable and its lightweight. The mycelium of a commercial mushroom species, Pleurotus ostreatus (PO), is used to fabricate MBC for packaging materials. Another species, Pleurotus pulmonarius (PP), prefers warmer weather, making it more common in tropical countries. Nevertheless, there is a lack of studies of PP mycelium-based composites and their mechanical and physical properties. This study investigated the physical and mechanical properties of PP mycelium/sawdust composite and compared to PO mycelium/sawdust composite. The results showed that the average density of PP/sawdust and PO/sawdust composites were 292.14 and 272.17 kg/m3, respectively, which fell within the range of low-density polyurethane foam. The final mass gain due to water absorption into PO/sawdust specimens was 144.04%, 1.41 times lower than PP/sawdust specimens. Furthermore, PP/sawdust composite exhibited 7.5 times faster water absorption rate than PO/sawdust composite, indicating that PO/sawdust had better water resistance. The PP/sawdust composite produced an equivalent compressive modulus to the PO/sawdust composite under compression up to 1.34 MPa of maximum value. Thus, the PP/sawdust composite showed excellent potential for substitution of biodegradable packages made from PO/sawdust composite as they contributed the equivalent strength; however, the PO/sawdust composite exhibited superior water resistance to the PP/sawdust composite. Consequently, PO/sawdust should be more advantageous if the biodegradable packaging is required to be of strength as high as the low-density polyurethane foam and of compatible water resistance.
... However, lignin found in coir-pith prevents microorganisms from decomposing it as easily as sawdust, giving it a far longer shelf life than sawdust [7], [12]. The trial-and-error method is used to determine the 3:2 ratio [19]- [21]. The physical and chemical properties of raw materials used to develop the biocomposite samples are shown in Table 1. ...
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Mycelium biocomposite materials have been established as a sustainable alternative to polystyrene in single use applications like packaging. However only little investigations are done on improving their resistance to fire and heat, which can find use in newer applications. This paper focuses on the development and characterization of a mycelium-based sawdust-coir pith biocomposite material treated with a combination of fire-retardant compounds (borax and boric acid). The outcomes of fire resistance tests, such as flammability, flame penetration and rate of burning demonstrated a significant improvement in values with respect to untreated samples. However, samples having 30% boron compounds by weight in it exhibited the best fire resistance properties. The thermal analysis of treated samples indicated that the presence of fire-retardant chemicals has not significantly affected their thermal stability. The glass transition temperature (Tg) of treated mycelium composite material was found to be 212.75 °C against a value of 207.78 °C for untreated samples. The fire retardant treated mycelium composite samples having 30% boron by weight in it, exhibited an average sound absorption coefficient of 0.38 compared with a sound absorption coefficient of 0.29 for polyurethane foam. The prepared mycelium biocomposite has a self-extinguishing nature and exceptional fire resistance capabilities with an LOI value of 50%. The mechanical testing revealed that the presence of fire-retardant chemicals has significantly improved the flexural properties. However, only a marginal increase was visible in the compression strength of mycelium biocomposites.
... Za osnovo vodenja postopka smo uporabili blažji program sušenja, primeren za težje sušeče lesne vrste, razdeljen po fazah, s postopnim naraščanjem temperature od začetne 40 °C do končne 70 °C. Glivne biokompozite se suši pri temperaturah med 60 in 110 °C (Arifin & Yusuf, 2013;Islam et al., 2018Islam et al., , 2017Teixeira et al., 2018), kjer se višje temperature uporablja v kombinaciji s kontaktnim segrevanjem in tlačnim stiskanjem v stiskalnicah. S tem dosežemo propad glive, kar preprečuje rast gob iz končnega izdelka, obenem pa ne poškodujemo micelija, kar je ključno za doseganje ustreznih končnih lastnosti materiala. ...
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As the need for a circular economy grows, so does the need for new sustainable materials. Biocomposites made from fungi are a sustainable alternative to synthetic foams. The key to commercializing this technology is knowing how to produce large quantities of such materials with the appropriate properties. As part of our experimental work, we have produced a larger mycelium biocomposite with a low density, a volume of 47 litres and a length of two metres. The final fungal biocomposite was produced by growing the mycelium in three stages; first in culture bags, then in two larger moulds, which were combined in a third stage. We used a culture of Ganoderma resinaceum and a specially formulated substrate to achieve a low density. The final biocomposite with a density of 80 kg/m³ met the target dimensions, remained infection-free and withstood lighter loads. The main disadvantage of the material was the small surface indentations caused by air inclusions in the substrate when the mycelium-laden substrate was transferred to the moulds.
... Mycelium-based materials, where a fungal cellular mass propagates via hyphal tip extension and branching and results in a bottom-up microscopic fibrous network, are prominent examples of biological material fabrication (Fricker et al. 2007). The mycelium consists of a three-dimensional network of hyphae that are 2-30 µm in diameter (Islam et al. 2018). This growth process can be used to assemble fibrous networks needed in composites and non-woven materials for a range of applications (Jones et al. 2017(Jones et al. , 2018(Jones et al. , 2021. ...
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This work explored whether partial cellulose bioconversion with fungal mycelium can improve the properties of cellulose fibre-based materials. We demonstrate an efficient approach for producing cellulose-mycelium composites utilizing several cellulosic matrices and show that these materials can match fossil-derived polymeric foams on water contact angle, compression strength, thermal conductivity, and exhibit selective antimicrobial properties. Fossil-based polymeric foams commonly used for these applications are highly carbon positive, persist in soils and water, and are challenging to recycle. Bio-based alternatives to synthetic polymers could reduce GHG emissions, store carbon, and decrease plastic pollution. We explored several fungal species for the biofabrication of three kinds of cellulosic-mycelium composites and characterized the resulting materials for density, microstructure, compression strength, thermal conductivity, water contact angle, and antimicrobial properties. Foamed mycelium-cellulose samples had low densities (0.058 – 0.077 g/cm³), low thermal conductivity (0.03 – 0.06 W/m∙K at + 10 °C), and high water contact angle (118 – 140°). The recovery from compression of all samples was not affected by the mycelium addition and varied between 70 and 85%. In addition, an antiviral property against active MS-2 viruses was observed. These findings show that the biofabrication process using mycelium can provide water repellency and antiviral properties to cellulose foam materials while retaining their low density and good thermal insulation properties. Graphical Abstract
... When using dry mycelium as a material for packaging and construction, it is important to understand the mechanical behavior under tensile or compressive loads [36,37], while living pellet structures in biotechnological cultures are exposed to both normal and shear forces due to turbulent flow [38]. However, there is currently a lack of research on the mechanical behavior of mycelial network structures. ...
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Filamentous microorganisms enable the production of a wide range of industrially relevant substances, such as enzymes or active pharmaceutical ingredients, from renewable side products and waste materials. The microorganisms' growth is characterized by the formation of complex, porous networks (mycelium) of tubular, multi-branched cells (hyphae). The mycelium is increasingly used in textiles, packaging, food and construction materials, in addition to the production of chemical substances. Overall, the mycelium's mechanical behavior is essential to many applications. In submerged cultures, spherical hyphal networks (pellets) are formed. The pellets are subjected to mechanical stress during cultivation, which can lead to structural changes affecting product titer and process conditions. To numerically investigate the mechanical behavior of pellets under normal stresses, the discrete element method (DEM) was used for the first time to simulate pellet compression. Initially, pellet structures were generated using a biological growth model and represented by a flexible fiber model. Force–displacement curves were recorded during compression to investigate the influencing factors. The effects of pellet size, fiber segment length, biological growth and DEM model parameters were studied. A strong influence of the growth parameters on the radial hyphal fraction and thus on the compression force was shown. Furthermore, the mechanical properties of the fiber joints significantly determined the pellet mechanics in the considered compression range. Overall, the simulation approach provides a novel tool for the digital investigation of stress on different mycelia, which may be used in the future to enhance mycelial structures through genetic and process engineering methods.
... A mycelium itself is a biopolymer network, properties of which depend on individual filament behavior [3]. The properties of mycelial-developed composites (including their porosity) can also vary depending on their substrates [4][5][6][7]. Modifications of pure mycelium material have allowed for an even wider adaptation of their properties, adding, for example, hydrophobicity and elasticity [8,9], as well as thermodynamic and physical mechanical properties of biocomposites based on mycelium. A review is given by Girometta et al. [1], who mention that mycelium bio-composites demonstrate the same accuracy in the results of research as synthetic materials or monocomponent natural materials in relation to mechanical and thermodynamic parameters. ...
... They mentioned that, when stretched, the reaction of the material is a linear elastic one. An analysis of mycelium-based particulate composite mechanics is given by Islam et al. [6]. They mentioned that composite properties are largely insensitive to the size of the particles for this volumetric fraction of the filler. ...
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Balanced and sustainable development has challenges in utilizing the best efficiency technologies , using new types of materials with reduced environmental impact, including composite types, reusable materials, and easily recyclable consumer adaptable products. One understudied biologically produced material is mycelium, the scientifically studied and improved cultivation of which produces an environmentally friendly material with unique properties with a wide range of applications. In this work, filtration fillers from mycelia of different cultivation periods and their abilities to filter airflow from solid particles were experimentally studied. Numerical modeling studied the interaction and trapping of particles in the flow with the surface of mycelium filters. The results of the research revealed a high airflow filtration efficiency of more than 91%, as well as differences and advantages in the properties and structure of mycelia of different growth periods, and the need for further study of this biomaterial.
... With fungal sensors, there is a challenging question of how they could be integrated into large-scale structures while being kept alive. Academic and commercial interest is currently focused on the use of mycelium to bind lignocellulosic material into composites [148][149][150][151] and films, [152][153][154] which are then deactivated. The use of living fungi in materials presents unique challenges beyond those typically associated with fungal materials. ...
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Signaling pathways in fungi offer a profound avenue for harnessing cellular communication and have garnered considerable interest in biomaterial engineering. Fungi respond to environmental stimuli through intricate signaling networks involving biochemical and electrical pathways, yet deciphering these mechanisms remains a challenge. In this review, an overview of fungal biology and their signaling pathways is provided, which can be activated in response to external stimuli and direct fungal growth and orientation. By examining the hyphal structure and the pathways involved in fungal signaling, the current state of recording fungal electrophysiological signals as well as the landscape of fungal biomaterials is explored. Innovative applications are highlighted, from sustainable materials to biomonitoring systems, and an outlook on the future of harnessing fungi signaling in living composites is provided.