Mycelium-Based Composite Materials: Study of Acceptance.

Mycelium-based composites (MBCs) are alternative biopolymers for designing sustainable furniture and other interior elements. These innovative biocomposites have many ecological advantages but present a new challenge in aesthetics and human product acceptance. Grown products, made using living mycelium and lignocellulosic substrates, are porous, have irregular surfaces and have irregular coloring. The natural origin of these types of materials and the fear of fungus can be a challenge. This research investigated the level of human acceptance of the new material. Respondents were students of architecture who can be considered as people involved in interior design and competent in the design field. Research has been performed on the authors' prototype products made from MBCs. Three complementary consumer tests were performed. The obtained results measured the human reactions and demonstrated to which extents products made of MBCs were "likeable" and their nonobvious aesthetics were acceptable to the public. The results showed that MBC materials generally had a positive or not-negative assessment. The responses after the pairwise comparison of the MBC with wall cladding samples pointed out the advantage of ceramic reference material above the MBC based on an overall assessment. The respondents also believed that the chamotte clay cladding would be easier to fit into the aesthetics of a modern interior and would in better accordance with its style. Although the MBC was less visually appealing, the respondents nevertheless found it more interesting, original, and environmentally friendly. The experiments suggested that the respondents had double standards regarding MBCs. MBCs were generally accepted as ecological, but not in their own homes. All of these results support current and future applications of MBCs for manufacturing items where enhanced aesthetics are required.

Indole Derivatives Bearing Imidazole, Benzothiazole-2-Thione or Benzoxazole-2-Thione Moieties-Synthesis, Structure and Evaluation of Their Cytoprotective, Antioxidant, Antibacterial and Fungicidal Activities.

In the search for new bioactive compounds, a methodology based on combining two molecules with biological properties into a new hybrid molecule was used to design and synthesize of a series of ten indole derivatives bearing imidazole, benzothiazole-2-thione, or benzoxazole-2-thione moieties at the C-3 position. The compounds were spectroscopically characterized and tested for their antioxidant, antibacterial, and fungicidal activities. The crystal structures were determined for five of them. Comparison of the closely related structures containing either benzothiazole-2-thione or benzoxazole-2-thione clearly shows that the replacement of -S- and -O- ring atoms modify molecular conformation in the crystal, changes intermolecular interactions, and has a severe impact on biological activity. The results indicate that indole-imidazole derivatives with alkyl substituent exhibit an excellent cytoprotective effect against AAPH-induced oxidative hemolysis and act as effective ferrous ion chelating agents. The indole-imidazole compound with chlorine atoms inhibited the growth of fungal strains: Coriolus versicolor (Cv), Poria placenta (Pp), Coniophora puteana (Cp), and Gloeophyllum trabeum (Gt). The indole-imidazole derivatives showed the highest antibacterial activity, for which the largest growth-inhibition zones were noted in M. luteus and P. fluorescens cultures. The obtained results may be helpful in the development of selective indole derivatives as effective antioxidants and/or antimicrobial agents.

Fungi in Mycelium-Based Composites: Usage and Recommendations.

Mycelium-Based Composites (MBCs) are innovative engineering materials made from lignocellulosic by-products bonded with fungal mycelium. While some performance characteristics of MBCs are inferior to those of currently used engineering materials, these composites nevertheless prove to be superior in ecological aspects. Improving the properties of MBCs may be achieved using an adequate substrate type, fungus species, and manufacturing technology. This article presents scientifically verified guiding principles for choosing a fungus species to obtain the desired effect. This aim was realized based on analyses of scientific articles concerning MBCs, mycological literature, and patent documents. Based on these analyses, over 70 fungi species used to manufacture MBC have been identified and the most commonly used combinations of fungi species-substrate-manufacturing technology are presented. The main result of this review was to demonstrate the characteristics of the fungi considered optimal in terms of the resulting engineering material properties. Thus, a list of the 11 main fungus characteristics that increase the effectiveness in the engineering material formation include: rapid hyphae growth, high virulence, dimitic or trimitic hyphal system, white rot decay type, high versatility in nutrition, high tolerance to a substrate, environmental parameters, susceptibility to readily controlled factors, easy to deactivate, saprophytic, non-mycotoxic, and capability to biosynthesize natural active substances. An additional analysis result is a list of the names of fungus species, the types of substrates used, the applications of the material produced, and the main findings reported in the scientific literature.

Bioactive Propolis-Silane System as Antifungal Agent in Lignocellulosic-Polymer Composites.

Polymer composites with renewable lignocellulosic fillers, despite their many advantages, are susceptible to biodegradation, which is a major limitation in terms of external applications. The work uses an innovative hybrid propolis-silane modifier in order to simultaneously increase the resistance to fungal attack, as well as to ensure good interfacial adhesion of the filler-polymer matrix. Polypropylene composites with 30% pine wood content were obtained by extrusion and pressing. The samples were exposed to the fungi: white-rot fungus Coriolus versicolor, brown-rot fungus Coniophora puteana, and soft-rot fungus Chaetomium globosum for 8 weeks. Additionally, biological tests of samples that had been previously exposed to UV radiation were carried out, which allowed the determination of the influence of both factors on the surface destruction of composite materials. The X-ray diffraction, attenuated total reflectance-Fourier transform infrared spectroscopy, and mycological studies showed a significant effect of the modification of the lignocellulose filler with propolis on increasing the resistance to fungi. Such composites were characterized by no changes in the supermolecular structure and slight changes in the intensity of the bands characteristic of polysaccharides and lignin. In the case of systems containing pine wood that had not been modified with propolis, significant changes in the crystalline structure of polymer composites were noted, indicating the progress of decay processes. Moreover, the modification of the propolis-silane hybrid system wood resulted in the inhibition of photo- and biodegradation of WPC materials, as evidenced only by a slight deterioration in selected strength parameters. The applied innovative modifying system can therefore act as both an effective and ecological UV stabilizer, as well as an antifungal agent.

Chemical Changes of Wood Treated with Caffeine.

Earlier studies have revealed that wood treated with caffeine was effectively protected against decay fungi and molds. However, there is a need to establish how the caffeine molecule behaves after wood impregnation and how it can protect wood. The objective of the research was to characterize the interaction between caffeine and Scots pine (Pinus sylvestris L.) wood as well as to assess the stability of the alkaloid molecule in lignocellulosic material. For this purpose, an elementary analyzer was used to assess the nitrogen concentration in the treated wood. The results showed that caffeine is easily removed from the wood structure through large amounts of water. The changes occurring in the wood structure after impregnation were evaluated with regard to the results obtained by Fourier transform infrared (FTIR) spectroscopy of two model mixtures with caffeine and cellulose or lignin for the purpose of conducting a comparison with the spectrum of impregnated and non-impregnated samples. The observed changes in FTIR spectra involve the intensity of the C=O(6) caffeine carbonyl group and signals from guaiacyl units. It might indicate favorable interactions between caffeine and lignin. Additionally, molecular simulation of the caffeine's interaction with the guaiacyl ß-O-4 lignin model compound characteristic for the lignin structure using computational studies was performed. Consequently, all analyses confirmed that caffeine may interact with the methylene group derived from the aromatic rings of the guaiacyl group of lignin. In summary, scanning electron microscope (SEM) observations suggest that caffeine was accumulated in the lignin-rich areas of the primary walls.

Propolis and Organosilanes as Innovative Hybrid Modifiers in Wood-Based Polymer Composites.

The article presents characteristics of wood/polypropylene composites, where the wood was treated with propolis extract (EEP) and innovative propolis-silane formulations. Special interest in propolis for wood impregnation is due to its antimicrobial properties. One propolis-silane formulation (EEP-TEOS/VTMOS) consisted of EEP, tetraethyl orthosilicate (TEOS), and vinyltrimethoxysilane (VTMOS), while the other (EEP-TEOS/OTEOS) contained EEP, tetraethyl orthosilicate (TEOS), and octyltriethoxysilane (OTEOS). The treated wood fillers were characterized by Fourier transform infrared spectroscopy (FTIR), atomic absorption spectrometry (AAS), and X-ray diffraction (XRD), while the composites were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and optical microscopy. The wood treated with EEP and propolis-silane formulations showed resistance against moulds, including Aspergillus niger, Chaetomium globosum, and Trichoderma viride. The chemical analyses confirmed presence of silanes and constituents of propolis in wood structure. In addition, treatment of wood with the propolis-silane formulations produced significant changes in nucleating abilities of wood in the polypropylene matrix, which was confirmed by an increase in crystallization temperature and crystal conversion, as well as a decrease in half-time of crystallization parameters compared to the untreated polymer matrix. In all the composites, the formation of a transcrystalline layer was observed, with the greatest rate recorded for the composite with the filler treated with EEP-TEOS/OTEOS. Moreover, impregnation of wood with propolis-silane formulations resulted in a considerable improvement of strength properties in the produced composites. A dependence was found between changes in the polymorphic structures of the polypropylene matrix and strength properties of composite materials. It needs to be stressed that to date literature sources have not reported on treatment of wood fillers using bifunctional modifiers providing a simultaneous effect of compatibility in the polymer-filler system or any protective effect against fungi.

Mycelium-Based Composites in Art, Architecture, and Interior Design: A Review.

Mycelium-based composites (MBCs) have attracted growing attention due to their role in the development of eco-design methods. We concurrently analysed scientific publications, patent documents, and results of our own feasibility studies to identify the current design issues and technologies used. A literature inquiry in scientific and patent databases (WoS, Scopus, The Lens, Google Patents) pointed to 92 scientific publications and 212 patent documents. As a part of our own technological experiments, we have created several prototype products used in architectural interior design. Following the synthesis, these sources of knowledge can be concluded: 1. MBCs are inexpensive in production, ecological, and offer a high artistic value. Their weaknesses are insufficient load capacity, unfavourable water affinity, and unknown reliability. 2. The scientific literature shows that the material parameters of MBCs can be adjusted to certain needs, but there are almost infinite combinations: properties of the input biomaterials, characteristics of the fungi species, and possible parameters during the growth and subsequent processing of the MBCs. 3. The patent documents show the need for development: an effective method to increase the density and the search for technologies to obtain a more homogeneous internal structure of the composite material. 4. Our own experiments with the production of various everyday objects indicate that some disadvantages of MBCs can be considered advantages. Such an unexpected advantage is the interesting surface texture resulting from the natural inhomogeneity of the internal structure of MBCs, which can be controlled to some extent.

Antifungal, anticancer, and docking studies of colchiceine complexes with monovalent metal cation salts.

Complexes of colchiceine with monovalent cation perchlorates and iodides have been obtained and characterized by spectroscopic methods. DFT and spectroscopic studies reveal that the dihedral angle ω1-1a-12-12a , crucial for colchicine biological mechanism of action, that is, binding to tubulins depends on the diameter of the complexed metal cation. Biological tests indicated no antifungal properties of colchicine (it was active only toward A.pullulans), in contrast to its derivative-(colchiceine). Complexation of colchiceine with metal cations improved significantly the antifungal potency, even below MIC <1 µg/ml. The colchiceine complexes were more potent than colchiceine, and some of them were even more potent than the fungicidal standard IPBC. The highest potency of colchiceine complexes was noted against A. pullulans (MIC = 0.5 µg/ml). In contrast to the findings concerning antifungal potency, the anticancer studies showed complexes of colchicine more active (~IC50  = 2 nM) than those of colchiceine (~IC50  = 6 µM). MDA-MB-231 breast cancer cell lines and human lung fibroblasts CCD39Lu were also tested.

7-Deacetyl-10-alkylthiocolchicine derivatives - new compounds with potent anticancer and fungicidal activity.

A series of new semi-synthetic 7-deacetyl-10-alkylthiocolchicne derivatives with ethyl, n-propyl, i-propyl and n-butyl substituents were synthesised and characterised by spectroscopic methods, elemental analysis, DFT calculations and molecular docking simulations. All the synthesized compounds have been tested for fungicidal and anticancer activities against SKOV-3, LoVo, MCF-7, MDA-MB-231 and the lung-derived fibroblast CCD39Lu. All the new colchicine derivatives exhibit significantly higher cytotoxicity towards the SKOV-3 tumour cell line than the natural product - colchicine. The most effective cytotoxic agents were 7-deacetyl-10-n-buthylthiocolchicine and 7-deacetyl-10-i-propylthiocolchicine. Among all the compounds tested, 7-deacetyl-10-n-buthylthiocolchicine exhibited the highest fungicidal activity. Molecular modeling indicated that several mutations found in the ß-tubulin unit of the tested fungal strains are crucial for antifungal activity and selectivity of 7-deacetyl-10-n-buthylthiocolchicine. The obtained results may be useful for the development of selective colchicine derivatives as effective fungicidal and/or anticancer drugs.

Distinguishing the Signs of Fungal and Burial-Induced Degradation in Waterlogged Wood from Biskupin (Poland) by Scanning Electron Microscopy.

A scanning electron microscopy (SEM) investigation of pine (Pinus sylvestris) and oak (Quercus sp.) wood samples exposed to various types of natural degradation is presented with the aim of discussing the correct identification of multiple degradation signs in waterlogged wood. This is part of an experiment performed at the archeological site of Biskupin (Poland) to evaluate the dynamics of short-term wood degradation during reburial and the suitability of excavated wood as substrate for the fungal attack. The final aim is to support and inform the in situ conservation strategy currently applied to archeological woods. To replicate the burial conditions, wood samples were put into lake water and peat. The samples were removed from the burial environments after 4, 6, 8, and 10 years, and then exposed to laboratory-controlled attack by a brown rot fungus Coniophora puteana and a white rot fungus Coriolus versicolor. SEM images were acquired for all samples before and after the fungal attack. The results showed a slight degradation occurred in the burial environments (soft rot and bacteria). In addition, both typical and previously neglected features of fungal attack were observed, highlighting that the extent of the fungal decay varies according to the previous degree of wood degradation. Some comparisons are provided with archeological wood samples from the Biskupin site.