In Vitro Fermentation of Edible Mushrooms: Effects on Faecal Microbiota Characteristics of Autistic and Neurotypical Children

Abstract

Children with autism spectrum disorder (ASD) often suffer gastrointestinal disturbances consistent with gut microbiota (GM) alterations. Treatment with pro/prebiotics may potentially alleviate gut symptoms, but the evidence for prebiotics is scarce. This study aims to evaluate the effects of edible mushrooms (Pleurotus, Basidiomycota) and prebiotic compounds on GM composition and metabolite production in vitro, using faecal samples from autistic and non-autistic children. Specific microbial populations were enumerated after 24 h of fermentation by quantitative PCR, and the metabolic production was determined by gas chromatography. Higher levels of Prevotella spp. and Bifidobacterium spp. were measured in neurotypical children compared to ASD children. A total of 24 h fermentation of Pleurotus eryngii and P. ostreatus mushroom powder increased the levels of Bifidobacterium, while known prebiotics increased the levels of total bacteria and Bacteroides in both groups. Only P. eryngii mushrooms resulted in significantly elevated levels of total bacteria Bacteroides and Feacalibacterium prausnitzii compared to the negative control (NC) in the ASD group. Both mushrooms induced elevated levels of butyrate after 24 h of fermentation, while short-chain fructooligosaccharides induced increased levels of acetate in the ASD group, compared to NC. Overall, this study highlights the positive effect of edible mushrooms on the GM and metabolic activity of children with ASD.

The Gut–Organ Axis within the Human Body: Gut Dysbiosis and the Role of Prebiotics

“…and Bifidobacterium spp. compared to ASD children [15]. In the same pattern, the study of Ding et al [30] demonstrated that children with ASD showed an altered GM structure compared with children in the healthy control group.…”

“…This bidirectional communication within the gut-brain axis elucidates how messages from the GM influence brain function and how signals from the brain impact gastrointestinal physiology and gut microbial activity [17]. These bidirectional communications involve the central nervous system (CNS), intrinsic branches of the enteric nervous system (ENS), extrinsic parasympathetic and sympathetic branches of the autonomic nervous system (ANS), the hypothalamic-pituitary-adrenal axis (HPA), neuroimmune pathways (neurotransmitters, hormones, and neuropeptides), and the gut microenvironment [15,18]. The HPA axis, a component of the limbic system, is considered the central stress efferent axis that coordinates the organism's adaptive responses to all stressors.…”

“…According to the International Scientific Association for Probiotics and Prebiotics (ISAPP), prebiotics are substrates that are "selectively utilized by host microorganisms, conferring a health benefit" [14]. Fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), lactulose, and inulin are the most widely recognised prebiotics, whereas β-glucans derived from various mushroom species (e.g., Pleurotus eryngii) are potential prebiotic candidates [15]. Recently, whole-food-based treatments have been used to modulate the GM through potential synergistic interactions between food's various components [15].…”

“…Fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), lactulose, and inulin are the most widely recognised prebiotics, whereas β-glucans derived from various mushroom species (e.g., Pleurotus eryngii) are potential prebiotic candidates [15]. Recently, whole-food-based treatments have been used to modulate the GM through potential synergistic interactions between food's various components [15]. Restoration of the GM in various diseases with pro/prebiotics has been postulated, but evidence for the effects of prebiotics is scarce.…”