Effect of common foods as supplements for the mycelium growth of Ganoderma lucidum and Pleurotus ostreatus on solid substrates

The transition from a linear to a circular economy is urgently needed to mitigate environmental impacts and loss of biodiversity. Among the many potential solutions, the development of entirely natural-based materials derived from waste is promising. One such material is mycelium-bound composites obtained from the growth of fungi onto solid lignocellulosic substrates, which find applications such as insulating foams, textiles, packaging, etc. During growth, the fungus degrades and digests the substrate to create a web-like stiff network called mycelium. The development of the mycelium is influenced by several factors, including the substrate composition. As food waste accounts for nearly 44% of total municipal solid waste, incorporating food in the substrate composition could be a means to increase the nutrients absorbed by the fungus. In this paper, we study the effects of the addition of food supplements on the growth of two fungal species, Ganoderma lucidum and Pleurotus ostreatus. The substrates, the food supplements, and the mycelia are characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and optical microscopy. Our results show that addition of barley as a supplement significantly boosts the growth of G. lucidum and P. ostreatus. Using a common food as a nutritious enrichment for the development of mycelium is a simple and straightforward strategy to create waste-based mycelium-bound biocomposites for a large range of applications, on-site, therefore promoting a circular economy

Development of an extrudable paste to build mycelium-bound composites

Mycelium-bound composites are promising materials for sustainable packaging, insulation, fashion, and architecture. However, moulding is the main fabrication process explored to date, strongly limiting the ability to design the complex shapes that could widen the range of applications. Extrusion is a facile and low energy-cost process that has not yet been explored for mycelium-bound composites with design freedom and structural properties. In this study, we combine cheap, easily and commonly available agricultural waste materials, bamboo microfibres, chitosan, and mycelium from Ganodermalucidum, to establish a composite mixture that is workable, extrudable and buildable. We study the impact of bamboo fibre size, chitosan concentration, pH and weight ratio of bamboo to chitosan to determine the optimum growth condition for the mycelium as well as high mechanical stiffness. The resulting materials have thus low energy costs, are sustainable and can be shaped easily. The developed composition is promising to further explore the use of mycelium-bound materials for structural applications using agricultural waste

Temporal characterization of biocycles of mycelium-bound composites made from bamboo and Pleurotus ostreatus for indoor usage

Mycelium-bound composites (MBCs) are materials obtained by growing fungi on a ligno-cellulosic substrate which have various applications in packaging, furniture, and construction industries. MBCs are particularly interesting as they are sustainable materials that can integrate into a circular economy model. Indeed, they can be subsequently grown, used, degraded, and re-grown. Integrating in a meaningful biocycle for our society therefore demands that MBCs fulfil antagonistic qualities which are to be at the same time durable and biodegradable. In this study, we conduct experiments using MBCs made from the fungus species Pleurotus ostreatus grown on bamboo microfibers substrate. By measuring the variations of the mechanical properties with time, we provide an experimental demonstration of a biocycle for such composites for in-door applications. We found that the biocycle can be as short as 5 months and that the use of sustainable coatings is critical to increase the durability of the composites while maintaining biodegradability. Although there are many scenarios of biocycles possible, this study shows a tangible proof-of-concept example and paves the way for optimization of the duration of each phase in the biocycle depending on the intended application and resource availability

Mechanical Properties of Bamboo Through Measurement of Culm Physical Properties for Composite Fabrication of Structural Concrete Reinforcement

Bamboo fibers with high mechanical properties can be a sustainable alternative to synthetic fibers for application in fiber reinforced polymer composites. The first aim of this study is to evaluate the dependence of mechanical properties of Dendrocalamus asper, known as bamboo Petung from Indonesia, on physical properties of the culm, including culm diameter, wall thickness, height, moisture content and specific density. Correlations between mechanical properties including tensile strength, modulus of rupture and modulus of elasticity in flexure and tension and culm physical properties have been studied. The results demonstrate that specific density is directly correlated with all these mechanical properties of bamboo while the moisture content values are correlated only with value of modules of rupture. Although wall thicknesses value of the culm are correlated with all of the mechanical properties studied, the culm diameter was only correlated with modulus of rupture and modulus of elasticity in flexure. Therefore, measurements of the culm geometry and specific density of raw bamboo have the potential for rapid, non-destructive evaluations of the quality of the bamboo, particularly in nurseries and forests where there is limited access to testing facilities. The second aim of this study is to evaluate whether such tests allow for an evaluation of the mechanical potential of the bamboo for production of high performance bamboo fiber reinforced polymer composites. Use of these formulas is illustrated through a case study of bamboo composite reinforcement for structural concrete. Pull-out tests and beam testing using this composite successfully validate the usefulness of this strategy for sustainable construction

The characterization of oxaliplatin-induced peripheral neuropathy using electromyography in gastrointestinal cancer patients

Oxaliplatin-induced peripheral neuropathy (OIPN) is a common dose-dependent chemotherapy complication in gastrointestinal cancer (GIC). This side effect may restrict therapeutic dose elevation of oxaliplatin. Here, OIPN frequency and determinants of neuropathy appearance in oxaliplatin-treated GIC patients. A total of 102 GIC patients who underwent chemotherapy with fluorouracil, folinic acid and oxaliplatin (FOLFOX4) regimen participated in this longitudinal study. Electromyography (EMG) was accomplished for ulnar, radial, sural, peroneal nerves and superficial peroneal nerve (SPN) before, 3, and 6 months after treatment. National Cancer Institute-Common Toxicity Criteria V.3 and clinical version of the Total Neuropathy Score were used for the neuropathy diagnosis at six months after treatment onset. Of all entered patients, twelve people discontinued this study, and five patients passed away. About 85 patients remained three and six months after chemotherapy onset. Approximately 95% of patients three months after chemotherapy demonstrated OIPN manifestations. Finally, data for 81 patients having neuropathy were analyzed. Mean age of patient 64.0±10.9 years. There were about 3.7%, 30.9%, 63% grade III, II, I of neuropathy, respectively. Interestingly, a significant decrease in action potential (AP) amplitude of SPN, sural and radial nerves but not ulnar and peroneal was observed after treatment onset. However, only the ulnar nerve indicated a substantial deceleration of nerve conduction. Age, sex, weight, past medical diseases, smoking and acute neuropathy were not significantly associated with OIPN. The occurrence of OIPN is detectable by electrophysiological changes of SPN, radial, and sural nerves at three and six months after starting chemotherapy with the FOLFOX4 regimen

Wood-Veneer-Reinforced Mycelium Composites for Sustainable Building Components

The demand for building materials has been constantly increasing, which leads to excessive energy consumption for their provision. The looming environmental consequences have triggered the search for sustainable alternatives. Mycelium, as a rapidly renewable, low-carbon natural material that can withstand compressive forces and has inherent acoustic and fire-resistance properties, could be a potential solution to this problem. However, due to its low tensile, flexural and shear strength, mycelium is not currently widely used commercially in the construction industry. Therefore, this research focuses on improving the structural performance of mycelium composites for interior use through custom robotic additive manufacturing processes that integrate continuous wood fibers into the mycelial matrix as reinforcement. This creates a novel, 100% bio-based, wood-veneer-reinforced mycelium composite. As base materials, Ganoderma lucidum and hemp hurds for mycelium growth and maple veneer for reinforcement were pre-selected for this study. Compression, pull-out, and three-point bending tests comparing the unreinforced samples to the veneer-reinforced samples were performed, revealing improvements on the bending resistance of the reinforced samples. Additionally, the tensile strength of the reinforcement joints was examined and proved to be stronger than the material itself. The paper presents preliminary experiment results showing the effect of veneer reinforcements on increasing bending resistance, discusses the potential benefits of combining wood veneer and mycelium’s distinct material properties, and highlights methods for the design and production of architectural components

Engineering microbes to sense and eradicate Pseudomonas aeruginosa, a human pathogen

A synthetic genetic system is designed and characterized that allows Escherichia coli to sense and eradicate Pseudomonas aeruginosa, providing a novel antimicrobial strategy that could potentially be applied to fighting infectious pathogens

Engineering microbes to sense and eradicate a human pathogen

Synthetic biology has allowed us to design and construct new biological systems that have the potential to resolve important issues related to healthcare. Considering the stalled development of advanced antibiotics and the emergence of antibiotic-resistant pathogens, we must now strive to exploit synthetic biology approaches for designing a new treatment regimen for infectious diseases. In this study we engineer microbes to detect and kill a pathogen using synthetic biology principles. We synthesize a genetic system comprised of quorum sensing, killing, and lysing devices. This system enables Escherichia coli (E. coli) to sense and kill a pathogenic strain of Pseudomonas aeruginosa (P. aeruginosa) through the production and release of pyocin S5.To reach our objective, we first design and characterize individual devices to understand their functionalities, which help us to construct the final system and verify its behavior. In the following steps, we show that our engineered E. coli detects and kills planktonic state P. Aeruginosa, evidenced by a >99% reduction in viable cells. Moreover, we confirm that our engineered E. coli inhibits the formation of P. aeruginosa biofilm by 90%, leading to much sparser and thinner biofilm matrices. Finally, to further optimize our system, we develop mathematical models using Computer Aided Design (CAD) tools that simulate both the dynamic and static performance of standard parts. We model the pathogen-sensing device of our sensing-killing system that produces Green Fluorescent Protein (GFP) as reporter in the presence of Acyl Homoserine Lactone (AHL). The parameters of the model are based on experimental results. Since it is important that these models are searchable and readable by machines, standard SBML (System Biology Markup Language) format is used to store the model. All parts and reactions are fully annotated to enable easy searching, and the model follows the Minimum Information Requested In the Annotation of Models (MIRIAM) compliance as well as the Minimum Information About a Simulation Experiment (MIASE). The model accurately simulates experimental results. In this thesis, we demonstrate that E. coli carrying the genetic circuit to sense and kill P. aeruginosa may provide a novel synthetic biology-based antimicrobial strategy. This approach could potentially be applied to struggle P. aeruginosa as well as other infectious pathogens. With the help of CAD tools we also show that the sensing device behaves as expected. This method can be used to model other parts of our system in order to make the entire system fully predictable.DOCTOR OF PHILOSOPHY (SCBE

Application of Mycelium-Bound Composite Materials in Construction Industry: A Short Review

Mycelium-bound composite materials are a new class of sustainable and affordable biocomposites that have been recently introduced into packaging, fashion, and architecture as alternative to traditional synthetic materials. In recent years extensive investigation and research studies have been dedicated to explore methods of production and processing as well as to find potential applications for mycelium-bound composite materials. However, application of this novel biocomposite within the construction industry has been limited to only small-scale prototypes and exhibition installations. The problems with low mechanical properties, high water absorption and lack of standard methods for production and testing of mycelium-bound composite materials remain as main challenges that need to be addressed when used as non-structural or semi-structural elements. This short review aims to display the potential of mycelium-bound composite materials for their use within the construction sector in the form of thermal and acoustic insulation as well as replacement for drywalls and tiles. This review summarizes the main available information with regards to the properties of mycelium-bound composites that have been used in construction sector while suggesting the direction for the future research and development on these biocomposites for their applications within the construction industry.ISSN:2327-096

Mechanical properties of dense mycelium-bound composites under accelerated tropical weathering conditions

10.1038/s41598-021-01598-4Scientific Reports1112211