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MYCELIUM MATTERS - An interdisciplinary exploration of the fabrication and properties of mycelium-based materials
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Environmental pollution and scarcity of natural resources have led to an increased interest in developing more sustainable materials. The traditional construction industry, which is mostly based on the extraction of fossil fuels and raw materials, has therefore been called into question. Biological materials that are created by growing mycelium-forming fungal microorganisms on natural fibres can form a solution. In this process, organic waste streams – such as agricultural waste – are valorised, while biodegradable material is created at the end of its life cycle; a process fitting with the spirit of a circular economy. Despite this promise, these materials’ characteristics have remained mostly unexplored. More scientific insights into growing and fabrication processes are required before incorporating these biomaterials into our daily lives. Therefore, this dissertation’s main goal is to explore the principal factors affecting the biological and material properties of mycelium materials and to broaden the potential of new fabrication technologies for architectural applications using fungal organisms. Ultimately, the research provides novel insights and a comprehensive overview of several crucial aspects that come into play during the production of fungi-based lignocellulosic composites. A method for selecting fungal species that incorporates biological, chemical and mechanical performance criteria has been developed. The interaction between fungi and their feedstock and the material properties of different types of feedstocks are investigated. Then, the optimisation of mechanical properties with different types of additives is studied. A novel fabrication process to produce large-scale architectural formwork is developed. Finally, various digital additive fabrications and design strategies that improve the colonisation of the fungi in a given geometry are explored. This hybrid investigation across disciplines is guided by the motivation to explore the growth and fabrication possibilities of mycelium materials from a bioengineering, material engineering, computational fabrication and architectural perspective.
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... Architecture explores and designs MBCs' applications [46][47][48][49], and business management develops models and strategies [50]. Ultimately, multidisciplinary collaboration is paramount for driving innovation in MBCs development [49,51]. 24, 9, x FOR PEER REVIEW 4 of 25 ...
... Architecture explores and designs MBCs' applications [46][47][48][49], and business management develops models and strategies [50]. Ultimately, multidisciplinary collaboration is paramount for driving innovation in MBCs development [49,51]. [32] in a variety of fields around the world (modified from Sydor et al. [7], Li et al. [10]). ...
... Faster-growing species may expedite the manufacturing process, ensuring efficient colonization and high density on composite surfaces [20]. However, the optimal growth must align with the intended production schedule and efficiency goals [51]. Fourthly, bonding properties vary among fungal species, with some producing stronger natural binders that enhance substrate particle binding, contributing to improved material integrity in the MBCs [62]. ...
Mycelium-based green composites (MBCs) represent an eco-friendly material innovation with vast potential across diverse applications. This paper provides a thorough review of the factors influencing the production and properties of MBCs, with a particular focus on interdisciplinary collaboration and long-term sustainability goals. It delves into critical aspects such as fungal species selection, substrate type selection, substrate preparation, optimal conditions, dehydrating methods, post-processing techniques, mold design, sterilization processes, cost comparison, key recommendations , and other necessary factors. Regarding fungal species selection, the paper highlights the significance of considering factors like mycelium species, decay type, hyphal network systems, growth rate, and bonding properties in ensuring the safety and suitability of MBCs fabrication. Substrate type selection is discussed, emphasizing the importance of chemical characteristics such as cellulose, hemicellulose, lignin content, pH, organic carbon, total nitrogen, and the C: N ratio in determining mycelium growth and MBC properties. Substrate preparation methods, optimal growth conditions, and post-processing techniques are thoroughly examined, along with their impacts on MBCs quality and performance. Moreover, the paper discusses the importance of designing molds and implementing effective sterilization processes to ensure clean environments for mycelium growth. It also evaluates the costs associated with MBCs production compared to traditional materials , highlighting potential cost savings and economic advantages. Additionally, the paper provides key recommendations and precautions for improving MBC properties, including addressing fungal strain degeneration, encouraging research collaboration, establishing biosecurity protocols, ensuring regulatory compliance, optimizing storage conditions, implementing waste management practices, conducting life cycle assessments, and suggesting parameters for desirable MBC properties. Overall, this review offers valuable insights into the complex interplay of factors influencing MBCs production and provides guidance for optimizing processes to achieve sustainable, high-quality composites for diverse applications.
... The development of biocomposites as sustainable materials for engineering applications necessitates rigorous inspection protocols to ensure their quality and performance [98]. The internal and external structures of MBCs significantly influence their physical and mechanical properties, durability, and suitability for various applications [15,44]. Hence, standardizing the inspection methods for these structures is crucial for advancing the use of MBCs in industry. ...
... Firstly, the intended application and regulatory requirements play a crucial role. For instance, if these materials are intended for construction purposes, standards such as ISO 22007-2 for thermal insulation property [44] and ASTM E1050 for sound insulation absorption should be prioritized [15,111]. These standards ensure that the materials meet specific performance criteria necessary for building safety and comfort. ...
Mycelium-bound composites (MBCs) represent a promising advancement in bio-based building materials, offering sustainable alternatives for engineering and construction applications. This review provides a comprehensive overview of the current research landscape, production methodologies, and standardization ideas related to MBCs. A basic search on Scopus revealed over 250 publications on MBCs between 2020 and 2024, with more than 30% focusing on engineering and materials science. Key studies have investigated the physical and mechanical properties of MBCs, optimizing parameters such as substrate type, fungal species, incubation time, and post-processing to enhance material performance. Standardizing the inspection of MBC properties is crucial for ensuring quality and reliability. Various testing standards, including those from the American Society for Testing and Materials (ASTM), the International Organization for Standardization (ISO), the Japanese Industrial Standard (JIS), European Standards (EN), Deutsches Institut für Normung (DIN), and the Thai Industrial Standards Institute (TIS), are utilized to evaluate density, water absorption, compression strength, tensile strength, insulation, and other critical properties. This review highlights the distinction between lab-scale and apply-scale testing methodologies, emphasizing the need for comprehensive evaluation protocols. Additionally, the production process of MBCs involves critical steps like substrate preparation, fungal species selection, and mycelium growth, necessitating the implementation of good manufacturing practices (GMPs) to ensure consistency and quality. The internal and external structures of MBCs significantly influence their performance, necessitating standardized inspection methods using advanced techniques such as scanning electron microscopy (SEM), X-ray computed tomography (CT) scanning, and surface profilometry. By establishing robust inspection protocols and production standards, the industry can enhance the reliability and adoption of MBCs, contributing to innovations in materials science and promoting environmental sustainability. This review underscores the importance of interdisciplinary collaboration, advanced characterization tools, and regulatory frameworks to address challenges and advance the field of MBCs.
... Fuente: (Elsacker, 2021) Rodríguez (2006) afirma que es recomendable que el tamaño de partículas de los sustratos se encuentre entre 0.5 y 2 cm, dado que con este tamaño de partícula se han obtenido los mejores resultados de cultivo. ...
... Se emplean varios métodos para la esterilización del sustrato, lo que hace el sustrato inerte y óptimo para la inoculación del micelio sin contaminantes como bacterias u otros tipos de hongos que pudiesen estar presente en el sustrato. La esterilización puede suceder por la temperatura, como autoclave y pasteurización o tratamiento con productos químicos o microbianos agentes (Elsacker, 2021). En primer lugar, la autoclave del sustrato se puede realizar a diferentes temperaturas, entre 115 y 121°C y puede variar duraciones entre 15 y 28 minutos ( (Appels et al., 2019). ...
Diversas investigaciones han demostrado que actividades relacionadas al rubro de la construcción se consideran como una de las causantes del daño al medio ambiente, siendo parte de ello las acciones vinculadas con la fabricación de materiales de construcción.
Debido a esto es importante identificar nuevos procedimientos y materias primas que provean una mayor sostenibilidad para mitigar el efecto provocado al medio ambiente.
Como propuesta se ha planteado un trabajo de investigación para fabricar un material compuesto de micelio cultivado en sustratos de aserrín de caoba y aserrín de pino para determinar sus propiedades mecánicas. El hongo seleccionado ha sido obtenido en el Centro de Micología Tropical de la Universidad Nacional Autónoma de Honduras, denominado “Ganoderma Lucidum”, popularmente conocido como “hongo Reishi”.
Además de fabricar un material que pudiera ser sostenible, se ha recopilado información mediante diferentes fuentes bibliográficas en la web, como lo es la base de datos “Scielo” y biblioteca del CRAI de UNITEC, acerca de las resistencias a compresión de diferentes tipos de micelio para realizar un análisis comparativo y determinar los posibles usos en la industria de la construcción.
Para la investigación se han fabricado 9 probetas cilíndricas para determinar la resistencia a la compresión y la absorción de micelio cultivado en aserrín de pino, aserrín de caoba y semillas de maicillo, donde se han obtenido que el micelio cultivado en semillas de maicillo tiene una resistencia a la compresión de 0.36 Mpa y un porcentaje de absorción promedio del 28.44 %, así mismo se observó un bajo crecimiento del micelio en el aserrín de caoba y de pino.
Palabras clave: Ganoderma Lucidum, aserrín de pino, aserrín de caoba, resistencia a compresión.
... Regenerating biomass waste into new materials is an area of research being investigated through biological interactions. Microorganisms such as bacteria and fungi can use waste as a form of feedstock to grow pliable materials investigated in areas such as architecture and material innovations [5,7,12]. Because these materials are biologically derived, they seldom use landmass in their production creating a circular raw material that has been derived from waste [11,12]. ...
... Microorganisms such as bacteria and fungi can use waste as a form of feedstock to grow pliable materials investigated in areas such as architecture and material innovations [5,7,12]. Because these materials are biologically derived, they seldom use landmass in their production creating a circular raw material that has been derived from waste [11,12]. However, in order to manufacture these biomaterials into usable textile apparel, new creative manufacturing is required. ...
The need for circular textiles has led to an interest in the production of biologically derived materials, generating new research into the bioproduction of textiles through design and interdisciplinary approaches. Bacterial cellulose has been produced directly from fermentation into sheets but not yet investigated in terms of producing filaments directly from fermentation. This leaves a wealth of material qualities unexplored. Further, by growing the material directly into filaments, production such as wet spinning are made redundant, thus reducing textile manufacturing steps. The aim of this study was to grow the bio-material, namely bacterial cellulose directly into a filament. This was achieved using a method of co-designing with the characteristics of biological materials. The method combines approaches of material-driven textile design and human-centred co-design to investigate co-designing with the characteristics of living materials for biological material production. The project is part of a wider exploration of bio-manufacturing textiles from waste. The practice-based approach brought together biological sciences and material design through a series of iterative experiments. This, in turn, resulted in designing with the inherent characteristics of bacterial cellulose, and by doing so filaments were designed to be fabricated directly from fermentation. In this investigation, creative exploration was encouraged within a biological laboratory space, showing how interdisciplinary collaboration can offer innovative alternative bioproduction routes for textile filament production.
... However, they are often undervalued and misused. In these biomass-fungi composite materials, fungi grow through the biomass particles and bind them together [4,5]. The fungi species used in the relevant studies reported in the literature include Pleurotus ostreatus, Ganoderma lucidum, and Fomes fomentarius. ...
Petroleum-derived plastic materials are used to manufacture a wide range of products [...]
... The driving force of the research was to investigate the use of mycelium in combination with wood and to observe the symbiosis of two biomaterials with different properties: While the wood performs the larger structural part at first, the mycelium creates a complex living material infill. (Vanden Elsacker, 2021). ...
... Se utilizan varios métodos para esterilizar el sustrato, lo que lo vuelve inerte y más adecuado para la inoculación del micelio sin contaminantes como bacterias u otros tipos de hongos que puedan estar presentes en el sustrato. La esterilización se puede realizar por temperatura, como el autoclave y la pasteurización, o por tratamiento con productos químicos o agentes microbianos (Elsacker, 2021). En primer lugar, el autoclave de los sustratos se puede realizar a diferentes temperaturas de 115 a 121 °C y la duración puede variar de 15 a 28 minutos (Appels et al., 2019a). ...
Diversas investigaciones han demostrado la resistencia a la compresión del micelio cultivado
en diferentes tipos de sustratos, sin embargo, hay espacio para seguir investigando la
resistencia a la compresión y porcentaje de absorción del micelio cultivado en diferentes
tipos de sustratos debido a la falta de crecimiento del micelio en algunos sustratos como el
aserrín de pino y de caoba cultivados en Honduras en investigaciones pasadas.
Debido a esto es importante investigar las propiedades del micelio cultivado en sustratos
orgánicos encontrados con facilidad en Honduras, como lo es el aserrín de pino, casulla de
arroz y heno. El micelio utilizado han sido las especies Pleurotus Ostreatus y Ganoderma
Lucidum, obtenidas en el Centro de Micología Tropical de la Universidad Nacional Autónoma
de Honduras.
Se ha llevado a cabo la fabricación de 13 cilindros de micelio, 7 cilindros de micelio de
Pleurotus Ostreatus cultivados en semillas de maicillo; 3 cilindros de micelio de Pleurotus
Ostreatus cultivados en aserrín de pino y 3 cilindros de micelio de Ganoderma Lucidum
cultivados en semillas de maicillo. Adicionalmente se ha combinado aserrín de pino y aserrín
de pino combinado con casulla de arroz y heno, con micelio Pleurotus Ostreatus para
observar el crecimiento durante 14 días. Los cilindros de micelio han sido sometidos a
ensayos de resistencia a la compresión y se ha calculado el porcentaje de absorción a partir
de lo cual se realizó un análisis comparativo entre las diferentes probetas de micelio,
tomando en cuenta los resultados de los ensayos anteriores.
Para los cilindros de micelio de Pleurotus Ostreatus cultivado en semillas de maicillo se ha
obtenido una resistencia a la compresión de 0.03 MPa y un porcentaje de absorción de
43.10%; para los cilindros de Ganoderma lucidum una resistencia a la compresión máxima
de 1.91 MPa.
Palabras clave: Pleurotus Ostreatus, Ganoderma Lucidum, aserrín de pino, casulla de arroz,
heno, resistencia a la compresión.
... ). BC has also been explored as composite material, for example as a food source (Elsacker 2021) or as living component (Hoenerloh et al. 2022). While first steps have been made to test the viability of BC as architectural element of a façade (Morrow et al. 2015), this early-stage research is one of few. ...
In this paper we investigate the integration of living bacteria into a 3D printable biopolymer composite for architectural applications. We specifically focus on incorporating cellulose-producing bacteria to grow 3D bacterial cellulose in-situ as a localised protective skin on a printed geometry. To produce and test large-scale samples, the research relaxes controlled lab conditions and pursues a more resilient culturing method, a kombucha culture or SCOBY. This paper reports exploratory experiments that assess the compatibility of the living bacteria with the biopolymer composite matrix, the printability of this new material, and the ability to reactivate the bacteria post-printing to grow 3D bacterial cellulose films on the samples. Our findings show successful bacterial reactivation and significant bacterial cellulose growth. These findings contribute to the field by demonstrating a novel approach to creating printable engineered living materials, and by identifying their potential to enable localised adaptation in large scale architectural elements.
Living organisms have been progressively used by designers to propose alternative design outcomes aiming towards more ecological aspects. The design development and manufacturing of new materials or design components from living organisms are more achievable in textile, fashion, or product design than in architecture and construction due to the scale, multi-layer constraints, and requirements. The aim of this paper is to investigate the interdisciplinary framework, the opportunities, and limitations of introducing living organisms into the design process, including the implementation from the design ideas to prototyping until commercialization. In this paper, we focus on three types of living organisms: algae, bacteria, and fungi. Firstly, we overviewed and studied existing projects and experimentations to understand the design process and fabrication of living organisms in other domains in comparison to architecture. Secondly, we selected three case studies in architecture for each organism to analyze. We collected the data and conducted interviews with multidisciplinary experts involved in each case. Our findings show a better understanding of the potential to integrate living organisms in architectural design, the advantages, and the difficulties towards ecological awareness. The results from the interview and a comparative analysis show the advantages and constraints of each case. The future outlooks towards the use of living organisms as part of design in architecture are also discussed.
Adsorption of organic phase-change materials (PCMs) by the porous matrix of microfibrillar cellulose (MFC) is a simple and versatile way to prepare shape-stable phase-change composites, which are promising as sustainable thermoregulating additives to construction materials. However, due to MFC inherent morphology, the resulting composites have relatively low poured density that complicates their introduction in sufficient amounts, for instance, into mortar mixes. Unlike MFC, fungal mycelium has, by an order, less fibrils thickness and, thus, possesses significantly higher poured density. Herein, we studied the feasibility of fungal mycelium-based matrices as alternative biopolymeric porous supports for preparation of sustainable and shape-stable phase-change composites. Two methods were employed to prepare the porous mycelium-based supports. The first one was the solid-state fermentation, which resulted in partial biotransformation of MFCs to mycelium hyphae, while the second one was the liquid-state surface fermentation, used to cultivate the reference matrix of Trametes hirsuta hyphae. The phase-change composites were prepared by adsorption of model organic PCMs on porous biopolymer matrices. The mass ratio of support/PCM was 40/60 wt%. The composites were studied with respect to their structure, composition, poured density, latent heat storage properties, and thermal and shape stability. The employment of the partially transformed to mycelium-hyphae MFC fibers was found to be a suitable way to prepare phase-change composites with improved poured density while preserving a reasonable latent heat capacity and shape stability as compared to the MFC/PCM composites.
Living building materials (LBMs) were engineered that are capable of both biological and structural functions. LBMs were created by inoculating an inert structural sand-hydrogel scaffold with Synechococcus sp. PCC 7002, a photosynthetic cyanobacterium. The scaffold provided structural support for Synechococcus, which toughened the hydrogel matrix via calcium carbonate biomineralization. Temperature and humidity switches were utilized to regulate the metabolic activity of the microorganisms and achieve three successive regenerations of viable LBMs from one parent generation. Microbial viability in LBMs maintained in at least 50% relative humidity for 30 days was 9%–14%, which far exceeded literature values of microorganisms encapsulated in cementitious materials for similar timeframes (0.1%–0.4%). While structural function was maximized at ultradesiccated conditions, prolonged dehydration compromised microbial viability. Despite this tradeoff in biological-structural function, LBMs represent a platform technology that leverages biology to impart novel sensing, responsive, and regenerative multifunctionality to structural materials for the built environment.
Significant efforts exist to develop living/non-living composite materials—known as biohybrids—that can support and control the functionality of biological agents. To enable the production of broadly applicable biohybrid materials, new tools are required to improve replicability, scalability, and control. Here, the Hybrid Living Material (HLM) fabrication platform is presented, which integrates computational design, additive manufacturing, and synthetic biology to achieve replicable fabrication and control of biohybrids. The approach involves modification of multimaterial 3D-printer descriptions to control the distribution of chemical signals within printed objects, and subsequent addition of hydrogel to object surfaces to immobilize engineered Escherichia coli and facilitate material-driven chemical signaling. As a result, the platform demonstrates predictable, repeatable spatial control of protein expression across the surfaces of 3D-printed objects. Custom-developed orthogonal signaling resins and gene circuits enable multiplexed expression patterns. The platform also demonstrates a computational model of interaction between digitally controlled material distribution and genetic regulatory responses across 3D surfaces, providing a digital tool for HLM design and validation. Thus, the HLM approach produces biohybrid materials of wearable-scale, self-supporting 3D structure, and programmable biological surfaces that are replicable and customizable, thereby unlocking paths to apply industrial modeling and fabrication methods toward the design of living materials.
The photoelectrochemical (PEC) production of syngas from water and CO2 represents an attractive technology towards a circular carbon economy. However, the high overpotential, low selectivity and cost of commonly employed catalysts pose challenges for this sustainable energy-conversion process. Here we demonstrate highly tunable PEC syngas production by integrating a cobalt porphyrin catalyst immobilized on carbon nanotubes with triple-cation mixed halide perovskite and BiVO4 photoabsorbers. Empirical data analysis is used to clarify the optimal electrode selectivity at low catalyst loadings. The perovskite photocathodes maintain selective aqueous CO2 reduction for one day at light intensities as low as 0.1 sun, which provides pathways to maximize daylight utilization by operating even under low solar irradiance. Under 1 sun irradiation, the perovskite–BiVO4 PEC tandems sustain bias-free syngas production coupled to water oxidation for three days. The devices present solar-to-H2 and solar-to-CO conversion efficiencies of 0.06 and 0.02%, respectively, and are able to operate as standalone artificial leaves in neutral pH solution.
The construction industry faces severe problems resulting from low productivity and increasing shortages of skilled labor. The purposeful digitalization and automation of all relevant stages, from design and planning to the actual construction process appears to be the only feasible solution to master these urgent challenges. Additive concrete construction has a high potential to be a key part of the solution. In the first place, technologies are of interest which would enable large-scale, on-site manufacturing of concrete structures in accordance with the demands of contemporary architectural and structural design. The article at hand evaluates the state-of-the-art with respect to these requirements and presents the CONPrint3D concept for on-site, monolithic 3D-printing as developed at the TU Dresden. This concept is driven by the demands and boundary conditions of construction practice. It complies with common architectural norms, valid design codes, existing concrete classes and typical economic constraints. Furthermore, it targets the use of existing construction machinery to the highest possible extent. The interdisciplinary team of authors illuminates various perspectives on the new technology: those of mechanical engineering, concrete technology, data management, and construction management. Some representative results of completed work in these fields are presented as well.
This paper describes how 3D-printed formwork can be used to facilitate the integration of functional features in structurally optimised concrete slabs. The weight of concrete slabs represents the largest portion of the weight of a concrete framed, multi-storey building. Despite this significant share, slabs are usually designed as monolithic, oversized boxes due to various construction constraints. Optimised design alternatives, featuring funicular shapes, differentiated ribs, profiled soffits and hollow sections use significantly less material and can moreover integrate building services within the thickness of the slab, such as heating, cooling and ventilation. Nevertheless, both the optimised external geometry and the internal network of functional voids present very complex fabrication challenges for concrete. This is because standard commercial formwork systems are not suitable for bespoke designs. To address this limitation, this research demonstrates how fused-deposition 3D printing can be used for the fabrication of custom formwork for a functionally integrated concrete slab. The resulting prototype efficiently uses material and integrates provisions for an active beam ventilation system within the standard structural depth of the slab. All these intricate geometric features are achieved with an ultra-lightweight 3D-printed formwork, which weighs less than 15 kg for the 660 kg concrete slab.
The current physical goods economy produces materials by extracting finite valuable resources without taking their end of the life and environmental impact into account. Mycelium-based materials offer an alternative fabrication paradigm, based on the growth of materials rather than on extraction. Agricultural residue fibres are inoculated with fungal mycelium, which form an interwoven three-dimensional filamentous network binding the feedstock into a lightweight material. The mycelium-based material is heat-killed after the growing process. In this paper, we investigate the production process, the mechanical, physical and chemical properties of mycelium-based composites made with different types of lignocellulosic reinforcement fibres combined with a white rot fungus, Trametes versicolor. This is the first study reporting the dry density, the Young’s modulus, the compressive stiffness, the stress-strain curves, the thermal conductivity, the water absorption rate and a FTIR analyse of mycelium-based composites by making use of a fully disclosed protocol with T. versicolor and five different type of fibres (hemp, flax, flax waste, softwood, straw) and fibre processings (loose, chopped, dust, pre-compressed and tow). The thermal conductivity and water absorption coefficient of the mycelium composites with flax, hemp, and straw have an overall good insulation behaviour in all the aspects compared to conventional materials such as rock wool, glass wool and extruded polystyrene. The conducted tests reveal that the mechanical performance of the mycelium-based composites depends more on the fibre processing (loose, chopped, pre-compressed, and tow), and size than on the chemical composition of the fibres. These experimental results show that mycelium-composites can fulfil the requirements of thermal insulation and have the potential to replace fosile-based composites. The methology used to evaluate the suitability and selection of organic waste-streams proved to be effective for the mycelium-material manufacturing applications.
A kind of novel sustainable mycelium/cotton stalk composite were prepared in laboratory by growing white rot fungus of Ganoderma lucidum on cotton stalk and stored in a block mold followed by hot-pressing process. To improve the mechanical properties, the composites were, respectively, subject to water immersion prior to hot-pressing at various water uptake (20%, 30%, 40% and 50%). The mechanical properties including flexural and internal bonding properties were tested. The results showed that with increasing water uptake, the mechanical properties of the composites increased at first after reaching the maximum at water uptake of 30 wt% in accordance with the saturation point of cotton stalk. Therefore, the water contributed to the good interface between mycelium and cotton stalk particles, where the flexural and internal bonding strength met the standard for non-load bearing particleboard listed in ANSI A208.1-2016. However, at water uptake higher than 30 wt%, no further improvement occurred due to the excessive water located in cell lumen rather than in the cell wall.
Recent convergence of biotechnological and design tools has stimulated an emergence of new design practices utilizing natural mechanisms to program matter in a bottom-up approach. In this paper, the fibrous network of mycelium—the vegetative part of fungi—is employed to produce sustainable alternatives for synthetic foams. Current research on mycelium-based materials lacks essential details regarding material compositions, incubation conditions, and fabrication methods. The paper presents the results of ongoing research on employing mycelium to provide cleaner architecture and design products with sustainable lifecycles. The paper opens with a critical review of current projects, products, and scientific literature using mycelium in design and architecture. In the second section, material properties of varied fungi-substrate compositions and fabrication methods are evaluated and compared through changes in essential chemical parameters during fermentation, visual impression, water absorbency, and compression strength tests. Then, potential architecture and design implications related to the material properties are discussed. Results indicate a clear correlation between fungi, substrate, mold properties, and incubation conditions on final material characteristics, depicting a clear effect on material density, water absorbency, and the compressive strength of the final bio-composite. Finally, two primary case studies demonstrate implications for mycelium-based composites for circular design and architectural applications. The study shows that in order to produce desirable designs and performance within an inclusive circular approach, parameters such as material composition and fabrication conditions should be considered according to the target function of the final product throughout the design process.
A novel sustainable mycelium/cotton stalk composite was prepared in laboratory by growing cotton stalk with white rot fungus of Ganoderma lucidum in a block mold followed by hot-pressing process. The effects of pressing temperature (160, 180, and 200 °C) on physical, mechanical, and thermal properties of the composites were investigated. The results showed that with increasing pressing temperature, most properties of the composites increased significantly owing to the improved interfacial bonding at high temperature. However, it showed slight negative effect to the thermal decomposition resistance, while with increasing hot-pressing temperature, the thermal decomposition resistance of the composites was improved. After cultivation of mycelium, the structure of the cotton stalk particles was destroyed and main components, such as hemicelluloses and lignin degraded. However, after hot-pressing, the structures of the composites became compact and new chemical bonds between mycelium and cotton stalk particles occurred. The optimal group of this study was achieved under 200 °C hot-pressing, where the flexural and internal bonding strength was comparable to non-load bearing fibreboard.