## 1 Introduction
The achieving of unique self-grown materials is based on a revolutionary approach in materials science--\"Materials that are grown are better than manufactured\" [12; 13; 16]. The structural and macroscopic properties of mycelium-based bio-composites are highly influenced by the fungal species used, the type and chemical makeup of the substrates, and the conditions during cultivation and post-cultivation processing. These factors collectively determine whether the material is suited for non-structural, semi-structural, or specialized applications. Their low density, thermal conductivity and flammability, and high acoustic absorption make them potential substitutes for foams, plastics, and wood products used for packaging or insulation. Numerous studies have stated that various mushrooms, belonging mostly to the _Trametes_, _Gnanoderma_, and _Pleurotus_ genera, can be cultivated on a range of lignocellulosic waste, including wood chips, cottonseed hulls, corn cobs, sawdust, wheat and rice straw, coconut powder, and by-products from rose flowers and lavender straw, due to their enzyme systems and high colonization rates, turning them into mycelium-based biomaterials [2; 11; 12; 14; 17; 18; 19; 20; 21; 22; 23; 24]. The physical, mechanical, and structural properties of the MBCs are key characteristics that direct them toward non-structural, semi-structural, or specific applications [2; 9; 11; 12; 13; 19; 24; 25; 26; 11; 13; 19; 27; 28]. The characteristics of MBCs strongly depend on the type of the fungal species and substrates, as well as cultivation conditions and post-cultivation processing. Even a small deviation in the above parameters could result in obtaining bio-materials with different properties and functional aspects [10]. Numerous studies focus on investigating the physical and mechanical characteristics of MBCs derived from various agricultural substrates and fungal strains, as these properties are essential for their utilization in engineering applications. The apparent density of MBCs is a critical factor that affects mechanical properties, water absorption, and thermal conductivity, determining the overall competitiveness and suitability of these materials. Studies show a wide range of apparent densities (25-954 kg/m\({}^{3}\)), influenced by the type of natural lignocellulosic substrate and fungal colonization levels [9]. High water absorption of MBCs, attributed to high open porosity, poses a challenge to their effective applications [29]. Thermal conductivity varies between 0.025 and 0.105 W/mK, with lower values indicating better insulation [25; 30; 31; 32; 33; 34]. Compressive strength, ranging from 29 to 567 kPa, is pivotal for functional mycelium bio-materials, dependent on substrate type and fungal strain [29; 35; 36; 37; 38]. In contrast to the widely studied physical and mechanical properties, the biodegradability of MBCs remains a relatively neglected field of research despite many statements about their biodegradability. Biodegradation of hemp MBCs and wood MBCs by composting has been carried out by [PERSON] et al. [39]. The results show that the mass loss of hemp and wood MBCs after 12 weeks of biodegradation was above 70%. In order to deliver a novel proof of concept of the material's biodegradability, a modified soil burial test for ISO 20200 [40] has been used by [PERSON] et al. [41]. The weight loss of MBCs obtained from _T. versicolor_, _G. resinacum_, been wood, and hemp increases after 16 days of incubation in the soil and reaches final weight loss values within the range of 19.06-43.03%. When hardwood chips and hemp are used as substrates, the weight loss reaches 70% after 12 days of incubation, which is in accordance with the claims that many factors influence the disintegration of MBCs. Beyond simple disintegration, degradation of these materials can also enable resource recovery at the end of their life cycle. For example, using MBCs in anaerobic digestion may recover a certain amount of energy through biogas production [42].