Characterization, Antioxidant and Anti-Inflammation Capacities of Fermented Flammulina velutipes Polyphenols

Effects of Flammulina velutipes powder on the emulsion properties of chicken myofibrillar protein under low-salt conditions

This study aimed to investigate the influence of varying concentrations of Flammulina velutipes powder (FVP) (0, 4, 8, 12, 16, and 20 g L-1, based on FVP weight per liter of emulsion) on the stability, rheological properties, microstructure, and interfacial protein content of chicken myofibrillar protein (MP) emulsions under low-salt conditions. Visual assessment and the Turbiscan stability index revealed that the stability of MP emulsions improved with increasing FVP concentration. The greatest stability was achieved when the FVP concentration was 16 gL-1. The incorporation of FVP enhanced the elasticity and viscosity of the emulsions by forming a dense three-dimensional network structure. The droplet size of the emulsions initially decreased and then increased with increasing FVP concentration. The addition of FVP increased the amount of protein absorbed by the emulsion layer. Flammulina velutipes powder is promising as a stabilizer that could improve the emulsifying and functional properties of low-salt myofibrillar protein emulsions. © 2024 Society of Chemical Industry.

Whole-Genome Sequence Analysis of Flammulina filiformis and Functional Validation of Gad, a Key Gene for γ-Aminobutyric Acid Synthesis

Flammulina filiformis is one of the widely produced edible fungi worldwide. It is rich in γ-aminobutyric acid (GABA), a non-protein amino acid with important physiological functions in humans. To investigate the functions of key genes in the GABA metabolic pathway of F. filiformis, we isolated the monokaryon Fv-HL23-1 from the factory-cultivated F. filiformis strain Fv-HL23 and then sequenced and assembled the genome using the PacBio Sequel and Illumina NovaSeq sequencing platforms. The results showed that the genome comprised 140 scaffolds with a total length of 40.96 Mb, a GC content of 49.62%, an N50 of 917,125 bp, and 14,256 protein-coding genes. Phylogenetic analysis based on the whole genome revealed a close evolutionary relationship of Fv-HL23-1 with Armillaria mellea, Lentinula edodes, and Schizophyllum commune. A total of 589 carbohydrate-active enzymes were identified in the genome of Fv-HL23-1, suggesting its strong lignocellulose degradation ability, and 108 CYP450 gene family members were identified, suggesting important functions such as resistance to stress, secondary metabolite synthesis, and growth and development. The F. filiformis proteins glutamate decarboxylase 1 (Ff-GAD1) and glutamate decarboxylase 2 (Ff-GAD2), which may be responsible for GABA synthesis, were identified by protein alignment. Molecular docking analysis showed that Ff-GAD2 may have better catalytic activity than Ff-GAD1. To verify the function of Ff-gad2, its heterologous expression in the mycelia of the mononuclear Hypsizigus marmoreus was analyzed. Compared with wild type, the GABA content of mycelia was increased by 85.40-283.90%, the growth rate was increased by 9.39 ± 2.35%, and the fresh weight was increased by 18.44 ± 7.57%. Ff-GAD2 may play a catalytic role in GABA synthesis. In addition, the expression of the full-length Ff-gad2 gene was increased by 7.96 ± 1.39 times compared with the exon expression level in H. marmoreus mycelia, suggesting that the intron may contribute to the heterologous expression of Ff-GAD2. Based on whole-genome sequencing, we analyzed the enzyme system related to the important life activities of F. filiformis, focusing on the function of Ff-GAD, a key enzyme in the GABA synthesis pathway. The results lay a foundation for elucidating the GABA metabolism pathway of edible fungi and developing targeted breeding strategies for GABA-producing edible fungi.

Renoprotective Effects of Brown-Strain Flammulina velutipes Singer in Chronic Kidney Disease-Induced Mice Through Modulation of Oxidative Stress and Inflammation and Regulation of Renal Transporters

Cisplatin, widely used in chemotherapy, acts through mechanisms such as oxidative stress to damage the DNA and cause the apoptosis of cancer cells. Although effective, cisplatin treatment is associated with considerable side effects including chronic kidney disease (CKD). Studies on brown-strain Flammulina velutipes Singer (FVB) have shown its significant antioxidant and immunomodulatory effects. High-performance liquid chromatography (HPLC) confirmed that the FVB extract contained gallic acid and quercetin. This study investigated whether FVB extract can improve and protect against cisplatin-induced CKD in mice. C57BL/6 mice were used as an animal model, and CKD was induced through intraperitoneal cisplatin injection. FVB was orally administered to the mice for 14 consecutive days. N-acetylcysteine (NAC) was administered in the positive control group. Organ pathology and serum biochemical analyses were conducted after the mice were sacrificed. Significant dose-dependent differences were discovered in body mass, kidney mass, histopathology, renal function, inflammatory factors, and antioxidant functions among the different groups. FVB extract reduced the severity of cisplatin-induced CKD in pathways related to inflammation, autophagy, apoptosis, fibrosis, oxidative stress, and organic ion transport proteins; FVB extract, thus, displays protective physiological activity in kidney cells. Additionally, orally administered high doses of the FVB extract resulted in significantly superior renal function, inflammatory factors, antioxidative activity, and fibrotic pathways. This study establishes a strategy for future clinical adjunctive therapy using edible-mushroom-derived FVB extract to protect kidney function.

Unearthing the therapeutic benefits of culinary-medicinal mushrooms for humans: Emerging sustainable bioresources of 21st century

Global interest in mushroom farming techniques has grown in the last few years. Despite not making up a large amount of the human diet at the moment, the nutritional worth of mushrooms has prompted their usage. The three main segments of the global mushroom industry are wild, culinary (edible), and medicinal mushrooms. The quality food that mushrooms provide can be utilized to build agricultural ecosystems that are more sustainable for increasing productivity and enhancing the effectiveness of resource usage. This is mostly because mushrooms can be utilized for the recycling of biomass and remains from crop production. Culinary-medicinal mushrooms are becoming more and more important because of their nutrient density, dietary value, and health advantages. Given its many bioactive components, which include polysaccharides, proteins, vitamins, minerals, dietary fiber, and secondary metabolites, mushrooms have been utilized extensively as health foods. These mushrooms exhibit pharmacological activities and possess prebiotic and antibacterial capabilities. This review provides information on the latest advancements in the sustainable cultivation of mushrooms, particularly with nontraditional substrates, and their potential therapeutic uses. Furthermore, some of the newest developments and difficulties in the production of mushrooms are explored.

Research progress and future development potential of Flammulina velutipes polysaccharides in the preparation process, structure analysis, biology, and pharmacology: A review

In recent years, Flammulina velutipes (F. velutipes) has attracted consequential attention in various research fields due to its rich composition of proteins, vitamins, amino acids, polysaccharides, and polyphenols. F. velutipes polysaccharides (FVPs) are considered as key bioactive components of F. velutipes, demonstrating multiple physiological activities, including immunomodulatory, anti-inflammatory, and antibacterial properties. Moreover, they offer health benefits such as antioxidant and anti-aging properties, which have exceptionally valuable clinical applications. Polysaccharides derived from different sources exhibit a wide range of biomedical functions and distinct biological activities. The varied biological functions of polysaccharides, coupled with their extensive application in functional foods and clinical applications, have prompted a heightened focus on polysaccharide research. Additionally, the extraction, deproteinization, and purification of FVPs are fundamental to investigate the structure and biological activities of polysaccharides. Therefore, this review provides a comprehensive and systematic overview of the extraction, deproteinization, purification, characterization, and structural elucidation of FVPs. Furthermore, the biological activities and mechanisms of FVPs have been further explored through in vivo and in vitro experiments. This review aims to provide a theoretical foundation and guide future research and development of FVPs.

Effects of Fermentation on Bioactivity and the Composition of Polyphenols Contained in Polyphenol-Rich Foods: A Review

Polyphenols, as common components with various functional activities in plants, have become a research hotspot. However, researchers have found that the bioavailability and bioactivity of plant polyphenols is generally low because they are usually in the form of tannins, anthocyanins and glycosides. Polyphenol-rich fermented foods (PFFs) are reported to have better bioavailability and bioactivity than polyphenol-rich foods, because polyphenols are used as substrates during food fermentation and are hydrolyzed into smaller phenolic compounds (such as quercetin, kaempferol, gallic acid, ellagic acid, etc.) with higher bioactivity and bioavailability by polyphenol-associated enzymes (PAEs, e.g., tannases, esterases, phenolic acid decarboxylases and glycosidases). Biotransformation pathways of different polyphenols by PAEs secreted by different microorganisms are different. Meanwhile, polyphenols could also promote the growth of beneficial bacteria during the fermentation process while inhibiting the growth of pathogenic bacteria. Therefore, during the fermentation of PFFs, there must be an interactive relationship between polyphenols and microorganisms. The present study is an integration and analysis of the interaction mechanism between PFFs and microorganisms and is systematically elaborated. The present study will provide some new insights to explore the bioavailability and bioactivity of polyphenol-rich foods and greater exploitation of the availability of functional components (such as polyphenols) in plant-derived foods.

Effects of different drying treatments on the microstructure, free amino acids, volatile compounds and antioxidant activity of Flammulina velutipes root

Drying treatments are an effective method of preserving the beneficial properties of postharvest mushrooms. The effects of natural-air drying (ND), hot-air drying (HD), vacuum-freeze drying (FD), heat pump drying (HPD) and microwave-vacuum drying (MVD) on the microstructure, flavor- and health-related compounds of F. velutipes root were investigated. The results showed that FD had the least impact on the microstructure of F. velutipes root and its original porous fiber structure appeared complete. It also possessed the highest content of volatile compounds. MVD gave the highest contents of umami amino acids, total phenolics and total flavonoids, and its extract exhibited high antioxidant activity. In addition, different drying treatments had significant effect on the chemical components of F. velutipes root, with FD and MVD may be the potent drying strategies for preservation of flavor and nutraceuticals respectively. Therefore, our results provided essential data support for F. velutipes root processing and functional product development.

DPPH Radical Scavenging Activity of New Phenolics from the Fermentation Broth of Mushroom Morehella importuna

In recent years, wild morel mushroom species have begun to be widely cultivated in China due to their high edible and medicinal values. To parse the medicinal ingredients, we employed the technique of liquid-submerged fermentation to investigate the secondary metabolites of Morehella importuna. Two new natural isobenzofuranone derivatives (1-2) and one new orsellinaldehyde derivative (3), together with seven known compounds, including one o-orsellinaldehyde (4), phenylacetic acid (5), benzoic acid (6), 4-hydroxy-phenylacetic acid (7), 3,5-dihydroxybenzoic acid (8), N,N'-pentane-1,5-diyldiacetamide (9), and 1H-pyrrole-2-carboxylic acid (10), were obtained from the fermented broth of M. importuna. Their structures were determined according to the data of NMR, HR Q-TOF MS, IR, UV, optical activity, and single-crystal X-ray crystallography. TLC-bioautography displayed that these compounds possess significant antioxidant activity with the half DPPH free radical scavenging concentration of 1.79 (1), 4.10 (2), 4.28 (4), 2.45 (5), 4.40 (7), 1.73 (8), and 6.00 (10) mM. The experimental results would shed light on the medicinal value of M. importuna for its abundant antioxidants.

Water Extract from Brown Strain of Flammulina velutipes Alleviates Cisplatin-Induced Acute Kidney Injury by Attenuating Oxidative Stress, Inflammation, and Autophagy via PI3K/AKT Pathway Regulation

One of the most popular edible mushrooms in the world, Flammulina velutipes, has been shown to possess pharmacological properties such as anti-inflammatory and antioxidant properties. However, the potential activity of the brown strain of F. velutipes, a hybrid between the white and yellow strains, has not been thoroughly investigated. Numerous studies have been conducted in recent years to determine whether natural products can aid in improving or treating kidney diseases. In this study, we focused on the renoprotective effects of the brown strain of F. velutipes on cisplatin-induced acute kidney injury (AKI) in mice. Mice were pretreated with water extract from the brown strain of F. velutipes (WFV) from day 1 to day 10, with a single-dose intraperitoneal injection of cisplatin on day 7 to induce AKI. Our results demonstrated that WFV administration resulted in a reduction in weight loss and the amelioration of renal function and renal histological changes in mice with cisplatin-induced AKI. WFV improved antioxidative stress and anti-inflammatory capacity by increasing antioxidant enzymes and decreasing inflammatory factors. The expression of related proteins was determined via Western blot analysis, which showed that WFV could improve the expression of apoptosis and autophagy. We used the PI3K inhibitor Wortmannin and found that WFV achieved a protective effect by modulating the PI3K/AKT pathway and the expression of autophagy. Overall, WFV as a natural substance could be used as a new therapeutic agent for AKI.

Enokitake Mushroom and Its Active Component, Adenosine, Which Restores Testosterone Production in Impaired and Fatigued Mouse Models

Several studies have reported the effects of the consumption of various mushroom species on the testes in animal experimental models. Mushrooms, including enokitake mushrooms (Flammulina velutipes), and vegetables contain adenosine may affect testosterone production. Here, we aimed to elucidate the effects of enokitake and its active component, adenosine, on testosterone production in primary cultures of testicular cells in vivo using mice models and in vitro. The administration of enokitake ethanolic extract increased testosterone production in the cisplatin-impaired mouse model. The direct effect of mushroom extracts on testicular cells was examined and liquid chromatography-mass spectrometry analysis confirmed that the mushroom- and vegetable-induced increase in testosterone production mainly involved adenosine. Additionally, the administration of enokitake extract or adenosine to wet floor fatigue model mice promoted testicular testosterone production and enhanced Leydig cell function through insulin-like peptide three level upregulation. Structurally related compounds, including cordycepin, showed lower bioactivity than adenosine. This study showed that the ingestion of adenosine-containing mushrooms and vegetables may effectively increase testicular testosterone production. We conclude that mushrooms with a relatively high adenosine content, such as enokitake, may be useful against aging and fatigue.

Corrigendum: Compounds purified from edible fungi fight against chronic inflammation through oxidative stress regulation

[This corrects the article DOI: 10.3389/fphar.2022.974794.].

Research Progress on Absorption, Metabolism, and Biological Activities of Anthocyanins in Berries: A Review

Berries, as the best dietary sources for human health, are rich in anthocyanins, vitamins, fiber, polyphenols, essential amino acids, and other ingredients. Anthocyanins are one of the most important bioactive components in berries. The attractive color of berries is attributed to the fact that berries contain different kinds of anthocyanins. Increasing research activity has indicated that anthocyanins in berries show various biological activities, including protecting vision; antioxidant, anti-inflammatory and anti-tumor qualities; inhibition of lipid peroxidation; anti-cardiovascular disease properties; control of hypoglycemic conditions; and other activities. Hence, berries have high nutritional and medicinal values. The recognized absorption, metabolism, and biological activities of anthocyanins have promoted their research in different directions. Hence, it is necessary to systematically review the research progress and future prospects of anthocyanins to promote a better understanding of anthocyanins. The absorption, metabolism, and biological activities of anthocyanins from berries were reviewed in this paper. The findings of this study provide an important reference for basic research, product development and utilization of berries' anthocyanins in food, cosmetics, and drugs.

Aloe Vera-Fermented Beverage Ameliorates Obesity and Gut Dysbiosis in High-Fat-Diet Mice

Aloe vera has been proven to have various medicinal properties, including anti-inflammatory and anti-obesity functions. However, the effects of Aloe vera-fermented beverages (AFB) on obesity and its complications are still not clear. In this study, HepG2 cells in high-fat environment and high-fat diet (HFD) mice were used to investigate the potential obesity-preventing function of AFB. We found that AFB intervention decreased the amount of lipid droplets of HepG2 cells, suppressed the body weight gain and adipose accumulation, and reduced the serum contents of total cholesterol (TC), alanine aminotransferase (ALT), and interleukin 10 (IL-10) of HFD-mice. In addition, it also changed the composition of the gut microbiota. The ratio of Firmicutes/Bacteroidetes was decreased, while the relative abundance of Muribaculaceae, Alistipes and Rikenellaceae_RC9_gut_group was increased after the administration of AFB compared with HFD-mice. These results demonstrated that AFB can prevent diet-induced obesity (DIO) and provides a new option to modulate obesity-related gut dysbiosis.

Flammulina velutipes stem regulates oxidative damage and synthesis of yolk precursors in aging laying hens by regulating the liver-blood-ovary axis

Egg production levels in late laying hens are negatively correlated with increasing age. Decreased liver and ovarian function in aging laying hens is accompanied by decreased antioxidant capacity, reproductive hormone levels, and follicular development, resulting in decreased synthesis of yolk precursors. The golden needle mushroom (Flammulina velutipes) has been reported to exhibit anti-inflammatory, antioxidant, and hypolipidemic properties. We aimed to reveal the therapeutic effects of F. velutipes stem (FVS) on liver-blood-ovary axis and investigate the underlying mechanisms. A total of 360 sixty-seven-wk-old laying hens were randomized into 4 treatment groups: 1) basal maize-soybean meal diet (CON); 2) basal maize + 20 g/kg FVS (2% FVS); 3) basal maize + 40 g/kg FVS (4% FVS); and 4) basal maize + 60 g/kg FVS (6% FVS). FVS groups demonstrated significantly increased egg production and ovarian development compared with the CON group. The addition of FVS increased the levels of antioxidant enzymes (GSH-Px, T-SOD, and T-AOC) in the liver, serum, and ovaries and decreased malondialdehyde levels by regulating the expression of proteins related to the Keap1-Nrf2/ARE signaling pathway. Additionally, FVS significantly decreased ovarian apoptosis by regulating Bax, Bcl-2, and caspase3 mRNA and protein expression levels. FVS significantly increased the expression levels of estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone and their respective receptors. With increased levels of estradiol transported to the liver through the bloodstream, targeted binding to estrogen receptor (ER)-α and ER-β led to significant increases in ApoVLDL II, ApoB, and VTG II mRNA expression associated with yolk precursor synthesis. FVS decreased the levels of triglyceride and total cholesterol and significantly increased the expression of lipid metabolism, and transport-related mRNAs (FAS, PPAR-a/γ, and MTTP) in the liver. Therefore, the dietary supplementation of FVS can maintain the productive performance of aging laying hens by alleviating the degree of oxidative stress and regulating the transport of functional substances along the liver-blood-ovary axis, thereby improving the synthesis of yolk precursors.

Fermented Minor Grain Foods: Classification, Functional Components, and Probiotic Potential

Fermented minor grain (MG) foods often have unique nutritional value and functional characteristics, which are important for developing dietary culture worldwide. As a kind of special raw material in fermented food, minor grains have special functional components, such as trace elements, dietary fiber, and polyphenols. Fermented MG foods have excellent nutrients, phytochemicals, and bioactive compounds and are consumed as a rich source of probiotic microbes. Thus, the purpose of this review is to introduce the latest progress in research related to the fermentation products of MGs. Specific discussion is focused on the classification of fermented MG foods and their nutritional and health implications, including studies of microbial diversity, functional components, and probiotic potential. Furthermore, this review discusses how mixed fermentation of grain mixtures is a better method for developing new functional foods to increase the nutritional value of meals based on cereals and legumes in terms of dietary protein and micronutrients.

Biocompatible and antibacterial Flammulina velutipes-based natural hybrid cryogel to treat noncompressible hemorrhages and skin defects

Hemorrhage, infection, and frequent replacement of dressings bring great clinical challenges to wound healing. In this work, Flammulina velutipes extract (FV) and hydroxyethyl cellulose (HEC) were chemically cross-linked and freeze-dried to obtain novel HFV cryogels (named HFVn, with n = 10, 40, or 70 corresponding to the weight percentage of the FV content), which were constructed for wound hemostasis and full-thickness skin defect repair. Systematic characterization experiments were performed to assess the morphology, mechanical properties, hydrophilic properties, and degradation rate of the cryogels. The results indicated that HFV70 showed a loose interconnected-porous structure and exhibited the highest porosity (95%) and water uptake ratio (over 2,500%) with a desirable degradation rate and shape memory properties. In vitro cell culture and hemocompatibility experiments indicated that HFV70 showed improved cytocompatibility and hemocompatibility. It can effectively mimic the extracellular matrix microenvironment and support the adhesion and proliferation of L929 cells, and its hemolysis rate in vitro was less than 5%. Moreover, HFV70 effectively induced tube formation in HUVEC cells in vitro. The results of the bacteriostatic annulus confirmed that HFV70 significantly inhibited the growth of Gram-negative E. coli and Gram-positive S. aureus. In addition, HFV70 showed ideal antioxidant properties, with the DPPH scavenging rate in vitro reaching 74.55%. In vivo rat liver hemostasis experiments confirmed that HFV70 showed rapid and effective hemostasis, with effects comparable to those of commercial gelatin sponges. Furthermore, when applied to the repair of full-thickness skin defects in a rat model, HFV70 significantly promoted tissue regeneration. Histological analysis further confirmed the improved pro-angiogenic and anti-inflammatory activity of HFV70 in vivo. Collectively, our results demonstrated the potential of HFV70 in the treatment of full-thickness skin defects and rapid hemostasis.