Influence of a Biotechnologically Produced Oyster Mushroom (Pleurotus sajor-caju) on the Gut Microbiota and Microbial Metabolites in Obese Zucker Rats

Effects of a biotechnologically produced Pleurotus sapidus mycelium on gut microbiome, liver transcriptome and plasma metabolome of broilers

Submerged cultivation using low-value agro-industrial side streams allows large-scale and efficient production of fungal mycelia, which has a high nutritional value. As the dietary properties of fungal mycelia in poultry are largely unknown, the present study aimed to investigate the effect of feeding a Pleurotus sapidus (PSA) mycelium as a feed supplement on growth performance, composition of the cecal microbiota and several physiological traits including gut integrity, nutrient digestibility, liver lipids, liver transcriptome and plasma metabolome in broilers. 72 males, 1-day-old Cobb 500 broilers were randomly assigned to 3 different groups and fed 3 different adequate diets containing either 0% (PSA-0), 2.5% (PSA-2.5) and 5% (PSA-5.0) P. sapidus mycelium in a 3-phase feeding system for 35 d. Each group consisted of 6 cages (replicates) with 4 broilers/cage. Body weight gain, feed intake and feed:gain ratio and apparent ileal digestibility of crude protein, ether extract and amino acids were not different between groups. Metagenomic analysis of the cecal microbiota revealed no differences between groups, except that one α-diversity metric (Shannon index) and the abundance of 2 low-abundance bacterial taxa (Clostridia UCG 014, Eubacteriales) differed between groups (P < 0.05). Concentrations of total and individual short-chain fatty acids in the cecal digesta and concentrations of plasma lipopolysaccharide and mRNA levels of proinflammatory genes, tight-junction proteins, and mucins in the cecum mucosa did not differ between groups. None of the plasma metabolites analyzed using targeted-metabolomics differed across the groups. Hepatic transcript profiling revealed a total of 144 transcripts to be differentially expressed between group PSA-5.0 and group PSA-0 but none of these genes was regulated greater 2-fold. Considering either the lack of effects or the very weak effects of feeding the P. sapidus mycelium in the broilers it can be concluded that inclusion of a sustainably produced fungal mycelium in broiler diets at the expense of other feed components has no negative consequences on broilers´ performance and metabolism.

Modulation of the Gut Microbiota with Prebiotics and Antimicrobial Agents from Pleurotus ostreatus Mushroom

Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm mushroom contains bioactive compounds with both antimicrobial and prebiotic properties, which are distributed in the mushroom mycelium, fruiting body, and spent substrate. The mushroom is rich in nondigestible carbohydrates like chitin and glucan, which act as prebiotics and support the growth and activity of beneficial gut bacteria, thereby maintaining a healthy balance of gut microbiota and reducing the risk of antibiotic resistance. The bioactive compounds in P. ostreatus mushrooms, including polysaccharides (glucans, chitin) and secondary metabolites (phenolic compounds, terpenoids, and lectins), exhibit antibacterial, antiviral, and antifungal activities. When mushrooms are consumed, these compounds can help preventing the growth and spread of harmful bacteria in the gut, reducing the risk of infections and the development of antibiotic resistance. Nonetheless, further research is necessary to determine the efficacy of P. ostreatus against different pathogens and to fully comprehend its prebiotic and antimicrobial properties. Overall, consuming a diet rich in mushroom-based foods can have a positive impact on human digestion health. A mushroom-based diet can support a healthy gut microbiome and reduce the need for antibiotics.

Utilization of functional agro-waste residues for oyster mushroom production: Nutritions and active ingredients in healthcare

A large amount of agro-industrial residues are produced from the planting, production and processing of traditional Chinese herbs. As a tonic, edible, and economical herb, Codonopsis pilosula root has been extensively developed into medicine and functional food. However, thousands of tons of aerial parts (stems, leaves, flowers and fruits) have been directly discarded after harvest each year. To utilise agro-wastes, Pleurotus ostreatus was cultivated on a basal substrate supplemented with C. pilosula stems and leaves (CSL). Physicochemical analyses revealed that the basal substrate mixed with CSL was more abundant in cellulose, hemicellulose, and most of micronutrients such as K, Ca, Mg, S, Fe, Zn and Mo. After the first flush, the fruit bodies in CSL group exhibited a higher fresh weight, a wider average pileus diameter and a lower moisture level. Nutrition analyses presented a higher protein content and a lower fat content in mushrooms from CSL group compared with control group. Interestingly, 14 amino acids (glutamine, arginine, valine, leucine, and etc.) and 3 micronutrients (Se, Fe and Zn) were increased after CSL addition to the substrate. Based on untargeted metabolomics, a total of 710 metabolites were annotated. Compared with control group, there were 142 and 117 metabolites significantly increased and decreased in the CSL group. Most of them were grouped into classes of amino acids and peptids, fatty acids, carbohydrates, terpenoids, and etc. Moreover, an abundance of phytometabolites from Codonopsis were detected in P. ostreatus from CSL group, including polyacetylenes or polyenes, flavonoids, alkaloids, terpenoids, organic acids, and etc. UPLC-MS/MS results demonstrated that lobetyolin content in the CSL group samples was 0.0058%. In summary, the aerial parts of C. pilosula processed for use in the production of edible mushroom is an emerging strategy to converting agricultural waste into functional foods.

Edible Mushrooms as Novel Myco-Therapeutics: Effects on Lipid Level, Obesity and BMI

Obesity, usually indicated by a body mass index of more than 30 kg/m², is a worsening global health issue. It leads to chronic diseases, including type II diabetes, hypertension, and cardiovascular diseases. Conventional treatments for obesity include physical activity and maintaining a negative energy balance. However, physical activity alone cannot determine body weight as several other factors play a role in the overall energy balance. Alternatively, weight loss may be achieved by medication and surgery. However, these options can be expensive or have side effects. Therefore, dietary factors, including dietary modifications, nutraceutical preparations, and functional foods have been investigated recently. For example, edible mushrooms have beneficial effects on human health. Polysaccharides (essentially β-D-glucans), chitinous substances, heteroglycans, proteoglycans, peptidoglycans, alkaloids, lactones, lectins, alkaloids, flavonoids, steroids, terpenoids, terpenes, phenols, nucleotides, glycoproteins, proteins, amino acids, antimicrobials, and minerals are the major bioactive compounds in these mushrooms. These bioactive compounds have chemo-preventive, anti-obesity, anti-diabetic, cardioprotective, and neuroprotective properties. Consumption of edible mushrooms reduces plasma triglyceride, total cholesterol, low-density lipoprotein, and plasma glucose levels. Polysaccharides from edible mushrooms suppress mRNA expression in 3T3-L1 adipocytes, contributing to their anti-obesity properties. Therefore, edible mushrooms or their active ingredients may help prevent obesity and other chronic ailments.

Nutritional Characterization and Untargeted Metabolomics of Oyster Mushroom Produced Using Astragalus membranaceus var. mongolicus Stems and Leaves as Substrates

Astragalus membranaceus var. mongolicus (AMM) is an edible and medicinal material and is commonly used in East Asia. According to the pharmacopeia of China, the dried root of AMM is medicinal. However, the aerial parts of AMM are always directly discarded after harvest. The stems and leaves are also rich in active compounds, including saponins, flavonoids, terpenoids, and polysaccharides. To rationally use resources, waste products from AMM stems and leaves are useful substrates for edible fungus cultivation. Here, oyster mushroom (Pleurotus ostreatus var. florida) was cultivated on a basal substrate supplemented with AMM stems and leaves (AMM group). The nutritional and chemical composition of the fruiting body were analyzed by metabolomics and chemometrics. Our results showed that AMM addition to the substrate affected the fresh weight, moisture, fat, protein, and element concentrations, and amino acid composition of oyster mushroom. Moreover, 2,156 metabolites were detected and annotated based on the metabolomics data, of which 680 were identified as differentially expressed metabolites. Many active phytometabolites previously identified in AMM herbs were also detected in the metabolomics of oyster mushroom from AMM group, including 46 terpenoids, 21 flavonoids, 17 alkaloids, 14 phenylpropanoids, and 3 fatty acids. In summary, our results imply that oyster mushroom cultured with AMM stems and leaves might have very high nutritional therapy health care value.

Purslane (Portulacae oleracea L.) attenuates cadmium-induced hepatorenal and colonic damage in mice: Role of chelation, antioxidant and intestinal microecological regulation

BACKGROUND

Cadmium (Cd) is a representative pernicious metal, which has high biological toxicity. Its precaution through dietary administration is considered an important strategy. Considering that Portulaca oleracea L. (Por.L) has antioxidant, anti-inflammatory and other high medicinal value, and purslane insoluble dietary fiber (PIDF) has good binding property to metal ions, they could be good methods for Cd-induced biotoxicity therapy.

PURPOSE

To investigate the beneficial effects of Por.L or PIDF against Cd-induced subchronic toxicity and identify its underlying mechanisms.

STUDY DESIGN AND METHODS

C57BL/6 male mice (n = 12) were received 100 mg l^-1 CdCl₂ in water for 8 weeks. Mice were divided into four groups: Control, Cd-treated, 8% Por.L + Cd, and 8% PIDF + Cd. Histological evaluation, inductively coupled plasma-mass spectrometry, western blotting analysis, quantitative real time-PCR, gas chromatography-mass spectrometry and 16S rDNA analysis were used in the study.

RESULTS

Por.L treatment was able to inhibit inflammation and accumulation of Cd, enhance the activity of antioxidant enzymes, increase beneficial bacterial species of Akkermansia and Faecalibaculum and suppress the production of inflammatory cytokines in the colon, such as TNF-α, IL-6, IL-1β and IFN-γ. PIDF mainly relieved the toxicity of Cd by increasing the production of short chain fatty acids with anti-inflammatory functions and repressing the liver and kidney inflammation mediated by the TLR4/ MyD88/NF-κB pathway.

CONCLUSION

Our study has demonstrated that the antagonistic-Cd effects of Por.L might be mediated via chelation, antioxidation, regulation of intestinal microecology. Thus, our study provides a novel insight into Por.L as a promising function food for the anti-Cd biotoxicity. Por.L supplement could be considered as a potential coping strategy to alleviate hazardous effects in Cd-exposed humans.

Tandem mass tag-based proteomics for studying the effects of a biotechnologically produced oyster mushroom against hepatic steatosis in obese Zucker rats

Hepatic steatosis is a very common response to liver injury and often attributed to metabolic disorders. Prior studies have demonstrated the efficacy of a biotechnologically produced oyster mushroom (Pleurotus sajor-caju, PSC) in alleviating hepatic steatosis in obese Zucker rats. This study aims to elucidate molecular events underlying the anti-steatotic effects of PSC. Tandem mass tag (TMT) peptide labeling coupled with LC-MS/MS/MS was used to quantify and compare proteins in the livers of lean Zucker rats fed a control diet (LC), obese Zucker rats fed the same control diet (OC) and obese Zucker rats fed the control diet supplemented with 5% PSC (OPSC) for 4 weeks. Using this technique 3128 proteins could be quantified, out of which 108 were differentially abundant between the OPSC and OC group. Functional enrichment analysis of the up-regulated proteins showed that these proteins were mainly involved in metabolic processes, while the down-regulated proteins were involved in inflammatory processes. Results from proteomic analysis were successfully validated for two up-regulated (carbonic anhydrase 3, regucalcin) and two down-regulated (cadherin-17, ceruloplasmin) proteins by means of immunoblotting. SIGNIFICANCE: Valorization of low-grade agricultural waste by edible fungi, such as the mushroom Pleurotus sajor-caju (PSC), represents a promising strategy for the production of protein rich biomass since they boast of a unique enzyme system that has the ability to recover nutrients and energy from biodegradable waste. Herein, we describe the metabolic effects of PSC feeding using a combined quantitative proteomics and bioinformatics approach. In total, 108 proteins were identified to be regulated by PSC feeding in the liver of the obese rats. Complementary usage of a bioinformatics approach allowed us to decipher the mechanisms underlying the recently observed lipid-lowering and anti-inflammatory activity of PSC feeding in obese Zucker rats, namely a reduction of fatty acid synthesis, an improvement of hepatoprotective mechanisms and an enhancement of anti-inflammatory effects.