Polysaccharides with Antioxidative and Antiaging Activities from Enzymatic-Extractable Mycelium by Agrocybe aegerita (Brig.) Sing

A comprehensive review of secondary metabolites from the genus Agrocybe: Biological activities and pharmacological implications

The genus Agrocybe, situated within the Strophariaceae family, class Agaricomycetes, and phylum Basidiomycota, encompasses a myriad of species exhibiting significant biological activities. This review presents an integrative overview of the secondary metabolites derived from Agrocybe species, elucidating their respective biological activities and potential pharmacological applications. The metabolites under scrutiny encompass a diverse array of biological macromolecules, specifically polysaccharides and lectins, as well as a diverse group of 80 documented small molecular chemical constituents, classified into sterols, sesquiterpenes, volatile compounds, polyenes, and other compounds, their manifesting anti-inflammatory, anticancer, antioxidant, hepatoprotective, antimicrobial, and antidiabetic activities, these metabolites, in which polysaccharides exhibit abundant activities, underscore the potential of the Agrocybe genus as a valuable source of biologically active natural products. The present review emphasises the need for escalated research into Agrocybe, including investigations into the biosynthetic pathways of these metabolites, which could foster the development of novel pharmaceutical therapies to address various health challenges.

The benefits of edible mushroom polysaccharides for health and their influence on gut microbiota: a review

The gut microbiome is a complex biological community that deeply affects various aspects of human health, including dietary intake, disease progression, drug metabolism, and immune system regulation. Edible mushroom polysaccharides (EMPs) are bioactive fibers derived from mushrooms that possess a range of beneficial properties, including anti-tumor, antioxidant, antiviral, hypoglycemic, and immunomodulatory effects. Studies have demonstrated that EMPs are resistant to human digestive enzymes and serve as a crucial source of energy for the gut microbiome, promoting the growth of beneficial bacteria. EMPs also positively impact human health by modulating the composition of the gut microbiome. This review discusses the extraction and purification processes of EMPs, their potential to improve health conditions by regulating the composition of the gut microbiome, and their application prospects. Furthermore, this paper provides valuable guidance and recommendations for future studies on EMPs consumption in disease management.

Extraction, characterization, antioxidant and α-amylase inhibitory activities of (1 → 3)(1 → 6)-β-D-glucogalactan from Aspergillus niger ATCC 1004

The optimization of extraction, chemical characterization, and the evaluation of antioxidant activity and α-amylase inhibition capacities of the cell wall polysaccharides extracted from Aspergillus niger ATCC 1004 were studied in this paper. The response surface methodology through a factorial design of three levels indicated the optimal conditions for extraction: pH 13 and 180 min. Characterization results showed that the polysaccharide is glucogalactan, consisting of β-D-galactose-linked units (1 → 6) and β-D-linked glucose (1 → 3). The antioxidant activity was evaluated through three in vitro assays. It could effectively scavenge DPPH, ABTS and hydroxyl radicals with inhibition rates of 82.12%, 75.87% and 79.24, respectively, at 6.4 mg/mL, which were higher than those of the other polysaccharides. For inhibitory activity against α-amylase, a blocking effect of 53.7% was observed at a concentration of 2 mg/mL. Therefore, the cell wall polysaccharides of Aspergillus niger, (1 → 3)(1 → 6)-β-D-glucogalactan, seem to be a promising source for use as an antioxidant, in addition to holding an in vitro hypoglycemic potential.

Polysaccharide from Agrocybe cylindracea prevents diet-induced obesity through inhibiting inflammation mediated by gut microbiota and associated metabolites

Polysaccharide from Agrocybe cylindracea (ACP) has been demonstrated with various health benefits, but its anti-obesity effect and underlying mechanisms remain poorly understood. This study aimed to investigate the beneficial effects of ACP in high-fat diet (HFD)-induced obese mice by targeting gut microbiota and metabolites. 9-week ACP supplementation in HFD-fed mice reduced body weight, adipose accumulation, impaired insulin resistance, lipid levels, and liver injuries, which were negatively correlated to the pro-inflammatory factors, particularly tumor necrosis factor-alpha (TNF-α) and interleukin- 6 (IL-6). Moreover, ACP not only restored HFD-induced gut disorder, as indicated by the depletion of Desulfovibrio and Oscillibacter and the enrichment of the Bacteroides, Parabacteroides, Butyricimonas, and Dubosiella, but also positively regulated gut metabolites such as solavetivone and N-acetylneuraminic acid. Spearman's correlation analysis revealed that the ACP-altered microbes and metabolites were highly correlated with inflammation-related indexes. Notably, ACP greatly lowered the obesity-related TNF-α- and IL-6-levels partially by reducing Desulfovibrio and increasing Parabacteroides abundances, together with the associated decrease of solavetivone level. These findings suggest that ACP may be used as a prebiotic agent to prevent diet-induced obesity, and target-specific microbiota and metabolites may have unique therapeutic promise for inflammation-related diseases.

PET-CT and RNA sequencing reveal novel targets for acupuncture-induced lowering of blood pressure in spontaneously hypertensive rats

Manual acupuncture (MA) can be used to manage high blood pressure; however, the underlying molecular mechanism remains unknown. To explore the mechanism of acupuncture in the treatment of hypertension, Wistar Kyoto rats (WKYs) and spontaneously hypertensive rats (SHRs) were subjected to either MA stimulation or the corresponding sham procedure as a negative control (Sham-MA) for 1 week. PET-CT scans, transcriptomics and molecular biology were used to evaluate the effect of MA. The results show that MA can regulate blood pressure in SHRs, change the glucose metabolism of the paraventricular hypothalamus (PVH), and affect the mRNA and protein expression levels of differentially expressed genes in the PVH. These genes may lower blood pressure by regulating angiotensin, endothelial function and inflammation. These findings reveal that MA regulates multiple biological processes and genes/proteins of the PVH, and provide a solid theoretical basis for exploring the mechanisms by which MA regulates hypertension.

Ethnomycological Investigation in Serbia: Astonishing Realm of Mycomedicines and Mycofood

This study aims to fill the gaps in ethnomycological knowledge in Serbia by identifying various fungal species that have been used due to their medicinal or nutritional properties. Ethnomycological information was gathered using semi-structured interviews with participants from different mycological associations in Serbia. A total of 62 participants were involved in this study. Eighty-five species belonging to 28 families were identified. All of the reported fungal species were pointed out as edible, and only 15 of them were declared as medicinal. The family Boletaceae was represented by the highest number of species, followed by Russulaceae, Agaricaceae and Polyporaceae. We also performed detailed analysis of the literature in order to provide scientific evidence for the recorded medicinal use of fungi in Serbia. The male participants reported a higher level of ethnomycological knowledge compared to women, whereas the highest number of used fungi species was mentioned by participants within the age group of 61–80 years. In addition to preserving ethnomycological knowledge in Serbia, this study can present a good starting point for further pharmacological investigations of fungi.

Ageritin from Pioppino Mushroom: The Prototype of Ribotoxin-Like Proteins, a Novel Family of Specific Ribonucleases in Edible Mushrooms

Ageritin is a specific ribonuclease, extracted from the edible mushroom Cyclocybe aegerita (synonym Agrocybe aegerita), which cleaves a single phosphodiester bond located within the universally conserved alpha-sarcin loop (SRL) of 23-28S rRNAs. This cleavage leads to the inhibition of protein biosynthesis, followed by cellular death through apoptosis. The structural and enzymatic properties show that Ageritin is the prototype of a novel specific ribonucleases family named 'ribotoxin-like proteins', recently found in fruiting bodies of other edible basidiomycetes mushrooms (e.g., Ostreatin from Pleurotus ostreatus, Edulitins from Boletus edulis, and Gambositin from Calocybe gambosa). Although the putative role of this toxin, present in high amount in fruiting body (>2.5 mg per 100 g) of C. aegerita, is unknown, its antifungal and insecticidal actions strongly support a role in defense mechanisms. Thus, in this review, we focus on structural, biological, antipathogenic, and enzymatic characteristics of this ribotoxin-like protein. We also highlight its biological relevance and potential biotechnological applications in agriculture as a bio-pesticide and in biomedicine as a therapeutic and diagnostic agent.

Large inverted repeats identified by intra-specific comparison of mitochondrial genomes provide insights into the evolution of Agrocybe aegerita

Genomic structure and content of Agrocybe aegerita mitochondrial DNA contain essential information regarding the evolution of this gourmet mushroom. In this study, eight isolates of A. aegerita were sequenced and assembled into complete mitochondrial genomes. The mtDNA of the isolate Ag0067 contained two genotypes, both of which were quadripartite architecture consisting of two identical inverted repeats, separated by a small single-copy region and a large single-copy region. The only difference was opposite directions of the small single-copy region. The mtDNAs ranged from 116,329 bp to 134,035 bp, harboring two large identical inverted repeats. Genes of plasmid-origin were present in regions flanked by inverted repeat ID2. Most of the core genes evolved at a relatively low rate, whereas five tRNA genes located in corresponding regions of Ag0002:1-14000 and Ag0002:50001-61000 showed higher diversity. A long fragment inversion (10 Kb) was suggested to have occurred during the differentiation of two main clades, leading to two different gene orders. The number and distribution of the introns varied greatly among the A. aegerita mtDNAs. Fast invasion of short insertions likely resulted in the diversity of introns as well as other non-coding regions, increasing the variation of the mtDNAs. We raised a model about the evolution of the large repeats to explain the unusual features of A. aegerita mtDNAs. This study constructed quadripartite architecture of A. aegerita mtDNAs analogous to chloroplast DNA, proposed an interconversion model of the divergent mitochondrial genotypes with large inverted repeats. The findings could increase our knowledge of fungal evolution.