Mushrooms are capable of bioconverting organic residues into food. Understanding the relationship between high-quality yields and substrate biomass from these residues is critical for mushroom farms when choosing new strains. The objective of this exploratory study was, therefore, to analyze whether exotic mushrooms, namely, Pleurotus eryngii, Flammulina velutipes, and Agrocybe aegerita, could biologically convert the substrate into edible mushrooms as effectively as Lentinula edodes (baseline). Five experiments were carried out. Biological efficiency, biodegradability coefficient, mass balance and chemical characterization of the substrate were evaluated. Strategically hydrating the sawdust enabled L. edodes to achieve the greatest biodegradability and biological efficiency of 0.5 and 94.2 kg dt⁻¹, respectively. The values for L. edodes on wheat straw without hydration were 0.2 and 68.8 kg dt⁻¹, respectively. From 1000 kg of fresh substrate, P. eryngii produced 150.1 kg of edible mushrooms, making it technically competitive with L. edodes on wheat straw (195.9 kg). Hence, P. eryngii was the most reliable option for scaling among the exotic mushrooms. The analytical insights from our study provide further knowledge to advance the field’s prominence in high-throughput mushroom-producing systems, particularly for exotic mushrooms.

The shiitake mushroom (Lentinula edodes) is globally valued for its nutrition and medicinal properties. New technologies aim to increase production with less environmental impact, considering materials such as charcoal for substrate enrichment. This manuscript evaluated the effect of fine charcoal (FC) on the substrate formulation of two L. edodes strains (LED 20/11 and LED 20/12). The substrate consisted of 72% eucalyptus sawdust, 12.5% rice bran, 12.5% wheat bran, and 3% calcium carbonate (control treatment without charcoal). Treatments with FC proportionally reduced the use of sawdust, with doses of 1%, 2%, 4%, 8%, and 16% (relative to the substrate material). Yield, mushroom number, and mushroom weight were evaluated. The concentration of FC significantly affected the parameters analyzed, especially at the 4% dose. A negative correlation between mushroom number and weight was observed. For yield, the control treatment and the lowest dose of FC (1%) had the highest yields for the first harvest. Strain LED 20/12 showed lower yield variability due to the percentage of FC applied to the substrate. The incorporation of FC into the substrate for shiitake cultivation demonstrates efficacy; however, both the concentration and strain used are limiting factors for its applicability.

Although considered relatively sustainable, mushroom production generates significant waste at the end of cultivation. This study investigated the reuse of Spent Mushroom Substrate (SMS) to formulate new substrates for Pleurotus ostreatus cultivation. Substrates with high (higher bran content) and low (lower bran content) nitrogen levels were prepared and supplemented with 5%, 10%, or 20% SMS across three successive cycles P. ostreatus crops. Cultivation performance was evaluated based on biological efficiency, number of mushrooms, fresh weight, and number of clusters. Substrates were chemically characterized for total nitrogen, carbon, C/N ratio, electrical conductivity, and pH. The inclusion of SMS, along with reduced bran content, did not improve P. ostreatus yield and led to lower productivity compared to control substrates. No consistent correlations were observed between chemical variables and yield, although high-N substrates generally performed better. SMS reuse, under these conditions, is not viable, but results encourage further research.

Mushroom production is a sustainable practice but requires improvements, such as in Lentinula edodes (Berk) Pegler cultivation, which has high water and labor demands. In this context, this study proposed replacing the traditional primordia induction method by submersion with a water injection method. Two primordia induction methods (submersion and injection) and two cultivation block formats were compared: rectangular cube (2 kg) and cylindrical (3.5 kg). The substrate, composed of eucalyptus sawdust (72%), wheat bran (12.5%), rice bran (12.5%), CaCO₃ (1%), and CaSO₄ (2%), was inoculated with strain LED 19/11 and incubated for 80 days at 26 ± 5 °C and 85 ± 15% humidity. After this period, the blocks were washed and transferred to the production environment. Fruiting was induced either by submersion or water injection, and production was evaluated over four harvest flushes. The 2 kg blocks had higher yields with submersion (16.62%), while the 3.5 kg blocks responded better to injection (13.01%), showing more homogeneous production. Increasing the substrate quantity contributes to greater harvest stability across production cycles. Water injections proved to be a viable alternative, reducing handling and facilitating large-scale production. The use of this technique demonstrates great importance in reducing water use and also the need for labor in cultivation.

The valorization of agro-industrial residues is essential for advancing circular bioeconomy systems. This study integrated the natural colorant and edible mushroom industries by evaluating annatto (Bixa orellana) residues as substrates for Pleurotus ostreatus cultivation. Two experiments were conducted, testing field and industrial residues at three incorporation levels (32.5%, 42.5%, and 52.5%, w/w on a dry weight basis) combined with different supplementation strategies (corn bran, wheat bran, and their mixture) in a completely randomized design. Field residues showed greater yield and biological efficiency, while industrial residues exhibited higher variability. Total yield reached 38.92%, while the lowest value was 24.28%, representing an increase of up to 65% depending on residue origin and supplementation strategy. Biological efficiency exceeded 140% under optimal conditions, with gains above 70% compared to the lowest-performing treatments. Field residues also promoted a higher number of bunches and greater average bunch mass. Overall, substrate origin, supplementation, and residue proportion were decisive for fungal performance, demonstrating that annatto residues are promising low-cost substrates for scalable mushroom production within circular economy systems.