Degradative Ability of Mushrooms Cultivated on Corn Silage Digestate

Abstract

<jats:p>The current management practice of digestate from biogas plants involves its use for land application as a fertilizer. Nevertheless, the inadequate handling of digestate may cause environmental risks due to losses of ammonia, methane and nitrous oxide. Therefore, the key goals of digestate management are to maximize its value by developing new digestate products, reducing its dependency on soil application and the consequent air pollution. The high nitrogen and lignin content in solid digestate make it a suitable substrate for edible and medicinal mushroom cultivation. To this aim, the mycelial growth rate and degradation capacity of the lignocellulosic component from corn silage digestate, undigested wheat straw and their mixture were investigated on Cyclocybe aegerita, Coprinus comatus, Morchella importuna, Pleurotus cornucopiae and Pleurotus ostreatus. The structural modification of the substrates was performed by using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Preliminary in vitro results demonstrated the ability of P. ostreatus, P. cornucopiae and M. importuna to grow and decay hemicellulose and lignin of digestate. Cultivation trials were carried out on C. aegerita, P. cornucopiae and P. ostreatus. Pleurotus ostreatus showed the highest biological efficiency and fruiting body production in the presence of the digestate; moreover, P. ostreatus and P. cornucopiae were able to degrade the lignin. These results provide attractive perspectives both for more sustainable digestate management and for the improvement of mushroom cultivation efficiency.</jats:p>

Sustainable Management of Anaerobic Digestate: From Biogas Plant to Full-Scale Cultivation of Pleurotus ostreatus

“…Several previous works have shown that different species of Pleurotus are able to grow on various agro-residues, including grape pomace [2], hazelnut shells [23], banana leaves, sunflower stalk, cotton stalk, and sugar cane straw, proving their potentiality [10]. The mycelial growth of different fungi on digestate, including Pleurotus spp., has already been demonstrated in previous works [24,25]. Nevertheless, there is a general lack of research on the industrial application of this promising cultivation substrate.…”

A Comparative Analysis of Biodegradation and Bioconversion of Lentinula edodes and Other Exotic Mushrooms

“…Comparatively, P. eryngii (Km = 0.2; BE = 39.6 kg dt −1 ) converted more substrate into biomass, indicating that this species was the most effective exotic mushroom for biotransformation, followed by F. velutipes (Km = 0.15; BE = 30.4 kg dt −1 ) and A. aegerita (Km = 0.05; BE = 31.8 kg dt −1 ), based on biodegradability. A study by Fornito et al [33] on the degradative ability of mushrooms on silage consisting of corn reported incomplete colonization of the substrate by A. aegerita. The mycelial network of the exotic fungus was not capable of completely colonizing the substrate; thus, the bioconversion of labile C (an unstable fraction of the total C pool in raw materials) into biomass decreased, as did the biological efficiency, which is consistent with the lowest biodegradability of A. aegerita in this study.…”

Valorization of Hazelnut Shells as Growing Substrate for Edible and Medicinal Mushrooms

“…The substrates from in vitro test were analyzed after 30 days of mycelial growth, as previously described by Fornito et al, 2020 [44]. Parts of dried fruiting bodies (cap, hymenophore, and stipe) grown on the HS and WS-BC of each species were placed on the diamond crystal, and pressure was applied with a compression clamp.…”

“…In an earlier study, it was also used to show how physical harm had an effect on tissue structure and the aging process [43]. The most intriguing application of this technique is currently the degradation processes of various agricultural waste for mushroom cultivation [44,45].…”