Search Results (20)

Tremella fuciformis is high in polysaccharides, which have a structure made up of a straight chain of (1→3) α-D-mannan and side chains of glucuronic acid, xylose, and fucose. This study aimed to evaluate whether the non-animal hyaluronic acid extracted from Tremella fuciformis can maintain the chemical and physical characteristics of hyaluronic acid that ensure its biological functionality. Chemical and physical analyses such as hyaluronic content, screening of metals, purity, pH, nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (ATR/FTIR), and MALDI-TOF were performed. Chemical characterisation revealed that the most abundant polysaccharide in the extract was hyaluronic acid, accounting for ca. 87.76%, with a molecular weight above 2000 kDa. In addition, ATR/FTIR and NMR spectroscopy and MALDI-TOF analysis confirmed that Tremella fuciformis extract is a source of non-animal hyaluronic acid. In summary, every molecular attribute examined played a significant role in determining the functional qualities of the extract, indicating that a thoughtful choice of extraction technique can enhance its advantages. Full article

Tremella fuciformis Berk., also known as white fungus and snow fungus, is one of the important edible and medicinal mushrooms in China. The quality characteristics and metabolites of different T. fuciformis varieties directly affect the stability of their processed products. In this study, two new varieties of Tremella fuciformis, namely ’TYH-SD1’ (yellow) and ’TWH-SD2’ (white), which were obtained by the team through single-spore crossbreeding and its control varieties Tr21 (yellow) and Tr01 (white), were used as test materials. The characteristics and nutritional quality of the four varieties of substrates were comparatively analyzed, while metabolomics was employed to investigate the differences in flavor substances. The results demonstrate that TYH-SD1 and TWH-SD2 had a higher rehydration rate and faster rehydration speed compared with the control strains Tr21 and Tr01, with a smaller stem and higher yield. Notably, TWH-SD2 had a 29.06% increase in its rehydration rate and it had higher contents of crude polysaccharide and vitamin D₃. The surface of TYH-SD1 ear pieces exhibited a porous structure with a larger pore size and the surface of TWH-SD2 ear pieces displayed a surface characterized by connected gully-like protrusions and fewer indentations, which were significantly different from that of Tr21 and Tr01 ear pieces. The textural analysis shows that TYH-SD1 and TWH-SD2 ear pieces were softer and more elastic, with greater cohesion and recovery, indicating that they had high tensile and deformation recovery ability. Metabolomics analysis revealed that the relative content of aldehydes in the volatile flavor substances TYH-SD1 and TWH-SD2 was high in n-alpha-aldehyde, nonanaldehyde, and n-pentanal. The relative content of alkanes in TYH-SD1 was second only to that of aldehydes, with decane having the highest content, contributing to its more almond aroma, fruity aroma, and fat aroma. TWH-SD2 exhibited the highest concentration of alcohols, accounting for 43.57%, which may result in a clear, mushroom, and lipid odor. The above results will provide theoretical basis for the further production, processing, and application of the new varieties. Full article

Tremella fuciformis, as a traditional edible fungus in Asian countries, is rich in polysaccharides with a variety of bioactivities. Nevertheless, its high molecular weight and complex structure have caused limitations in its application and structural analysis. In this study, we successfully screened a Tremella fuciformis polysaccharide-degrading bacterium from the soil by enriching and screening. The mixed bacterium consisted mainly of Verrucomicrobium (55.4%) and Lysobacter (43.8%), which released extracellular enzymes that enabled the degradation of Tremella fuciformis polysaccharides. The functional annotation using microbiome and metagenome combined with bioinformatics revealed its active carbohydrate metabolism, binding, and catalysis. It exposed the enzymatic potential of the bacterium and provided a basis for the exploration of hydrolytic enzymes for hardly degradable polysaccharides in fungi. Full article

This research aimed to modify polysaccharides extracted from the edible mushroom Tremella fuciformis with gallic acid (GA) and to complex them with zinc ions. The functionalities of the modified Tremella fuciformis polysaccharides (TFPs) were investigated. Regarding antioxidant activity, TFP-GA demonstrated effective scavenging activity against DPPH radicals, nitric oxide, and hydrogen peroxide. Additionally, TFP-GA exhibited superior reducing ability toward Fe³⁺ and enhanced chelating activity toward Fe²⁺ compared to unmodified TFP. Notably, the TFP-GA conjugate outperformed GA in Fe²⁺-chelating activity. In terms of antimicrobial activity, the TFP-GA-Zn complex showed significantly improved antimicrobial effectiveness against S. aureus and E. coli compared to TFP-GA. Full article

In the present study, a heteromannan primarily composed of mannose, fucose, xylose, glucose, and arabinose at a molar ratio of 4.78:1.18:1:0.82:0.11 containing a low proportion of glucuronic acid with weight-average molecular weights of 3.6 × 10⁶ Da, named NTP, was prepared from the fruiting body of Tremella fuciformis. The anti-skin-aging effects of NTP on d-Galactose-induced aging mice and the biological mechanisms were investigated by an iTRAQ-based proteomics approach. NTP substantially mitigated skin aging characterized by a decreased loss of hydroxyproline and hyaluronic acid and reduced oxidative stress in the skin. Moreover, 43 differentially expressed proteins (DEPs) were identified in response to NTP, of which 23 were up-regulated and 20 were down-regulated. Bioinformatics analysis revealed that these DEPs were mainly involved in the biological functions of cellular and metabolic regulations, immune system responses, and structural components. The findings provided new insights into the biological mechanisms underlying the anti-skin-aging actions of T. fuciformis-derived polysaccharides and facilitated NTP applications in naturally functional foods. Full article

In this study, we have investigated the effects of Tremella fuciformis polysaccharide (TP) on the pasting, rheological, structural and in vitro digestive properties of Cyperus esculentus starch (CS). The results showed that the addition of TP significantly changed the pasting characteristics of CS, increased the pasting temperature and pasting viscosity, inhibited pasting, reduced the exudation of straight-chain starch and was positively correlated with the amount of TP added. The addition of the appropriate amount of TP could increase its apparent viscosity and enhance its viscoelasticity. The composite system of CS/TP exhibited higher short-range ordered structure and solid dense structure, which protected the crystal structure of CS, but was related to the amount of TP added. In addition, the introduction of TP not only decreased the in vitro digestion rate of CS and increased the content of slow-digestible starch (SDS) and resistant starch (RS), but also reduced the degree of digestion. Correlation studies established that TP could improve the viscoelasticity, relative crystallinity and short-range order of the CS/TP composite gel, maintain the integrity of the starch granule and crystalline structure, reduce the degree of starch pasting and strengthen the gel network structure of CS, which could help to lower the digestibility of CS. Full article

In this study, Tremella fuciformis polysaccharides (TFPs) were extracted by ultrasound-assisted enzymatic extraction (UAE) at different extraction parameters in order to explore the potential of ultrasound in intensifying the extraction yield. The effects of experimental conditions on the extraction yields were optimized using response surface methodology, with the optimal ultrasonic power of 700 W, temperature of 45 °C and time of 50 min. The kinetic analysis revealed that UAE significantly promoted the dissolution, diffusion and migration with the maximum yield of 26.39%, which was enhanced by 40.45% and 156.96% compared with individual ultrasonic extraction (UE) and enzymatic extraction (EE). According to the modified Fick’s second law of diffusion, the extraction process of TFPs illustrated a good linear correlation (R² ≥ 0.9), and the rate constant gradually elevated as the temperature increased from 25 to 45 °C, while the presence of ultrasound exerted a vital role in extracting TFPs. Regarding to the thermodynamic results, the positive values of ΔH and ΔG demonstrated that UAE, UE and EE were endothermic and unspontaneous processes. This study provides a theoretical basis for polysaccharide extraction processing. Full article

The structural characteristics and anti-inflammatory activity of Tremella fuciformis polysaccharides (TFPs) were investigated. The study showed that TFPs were mainly composed of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose. TFPs significantly inhibited monosodium urate (MSU)-induced inflammation of RAW264.7 cells, as well as the secretion levels of TNF-α, IL-1β, and IL-18 cytokines. The concentrations of malondialdehyde and reactive oxygen species in RAW264.7 macrophages were reduced, but superoxide dismutase activity was increased. RNA-Seq technology was applied to explore the mechanisms of TFPs ameliorating MSU-induced inflammation of RAW264.7 macrophages. Results revealed that TFPs significantly reduce MSU-stimulated inflammatory damage in RAW 264.7 cells by inhibiting signaling pathways like the hypoxia inducible factor-1 (HIF-1) signaling pathway and erythroblastic oncogene B (ErbB) signaling pathway. This study provides a foundation for TFPs to be developed as novel anti-inflammatory drugs. Full article

The purpose of this study was to investigate the effect of Tremella fuciformis polysaccharides on the physicochemical properties of freeze–thawed cone chestnut starch. Various aspects, including water content, crystallinity, particle size, gelatinization, retrogradation, thermal properties, rheological properties, and texture, were examined. The results revealed that moderate freezing and thawing processes increased the retrogradation of starch; particle size, viscosity, shear type, hinning degree, and hardness decreased. After adding Tremella fuciformis polysaccharide, the particle size, relative crystallinity, and gelatinization temperature decreased, which showed solid characteristics. Consequently, the inclusion of Tremella fuciformis polysaccharide effectively countered dehydration caused by freezing and thawing, reduced viscosity, and prevented the retrogradation of frozen–thawed chestnut starch. Moreover, Tremella fuciformis polysaccharide played a significant role in enhancing the stability of the frozen–thawed chestnut starch. These findings highlight the potential benefits of incorporating Tremella fuciformis polysaccharides in starch-based products subjected to freeze–thaw cycles. Full article

Anti-tumor activity of Tremella fuciformis polysaccharides (TFPS) has been widely reported, but its mechanism remains poorly understood. In this study, we established an in vitro co-culture system (B16 melanoma cells and RAW 264.7 macrophage-like cells) to explore the potential anti-tumor mechanism of TFPS. Based on our results, TFPS exhibited no inhibition on the cell viability of B16 cells. However, significant apoptosis was observed when B16 cells were co-cultured with TFPS-treated RAW 264.7 cells. We further found that mRNA levels of M1 macrophage markers including iNOS and CD80 were significantly upregulated in TFPS-treated RAW 264.7 cells, while M2 macrophage markers such as Arg-1 and CD 206 remained unchanged. Besides, the migration, phagocytosis, production of inflammatory mediators (NO, IL-6 and TNF-α), and protein expression of iNOS and COX-2 were markedly enhanced in TFPS-treated RAW 264.7 cells. Network pharmacology analysis indicated that MAPK and NF-κB signaling pathways may be involved in M1 polarization of macrophages, and this hypothesis was verified by Western blot. In conclusion, our research demonstrated that TFPS induced apoptosis of melanoma cells by promoting M1 polarization of macrophages, and suggested TFPS may be applied as an immunomodulatory for cancer therapy. Full article

Blanching is a critical step in the processing of Tremella fuciformis (T. fuciformis). The effects of different blanching methods (boiling water blanching (BWB), ultrasonic-low temperature blanching (ULTB), and high-temperature steam (HTS)) on the quality and moisture migration characteristics of T. fuciformis were investigated. The results showed that the T. fuciformis blanched by ULTB (70 °C, 2 min, 40 kHz, 300 W) had the best quality, including a brighter appearance, superior texture, and good sensory features, with a polysaccharide content of 3.90 ± 0.02%. The moisture migration characteristics of T. fuciformis after blanching exhibited four peaks, displayed strong and weak chemically bound water, immobilized water, and free water, whereas ULTB had a weak effect on the freedom of water in T. fuciformis. The study will provide the foundation for the factory processing of T. fuciformis. Full article

The chemical composition, macromolecular characteristics, and structure of four types of Tremella fuciform polysaccharides (TPS) were analyzed, including one TPS that was extracted in the laboratory (L-TPS) and three commercial TPS. The effects of pH on the properties of TPS emulsions were investigated by analyzing their zeta potential, particle size, apparent viscosity, and stability. The results showed that L-TPS presented a higher percentage content of protein (2.33%) than commercial TPS (0.73–0.87%), and a lower molecular mass (17.54 × 10⁶ g/mol). Thus, L-TPS exhibited the best emulsifying activity but gave poor emulsion stability. The droplet sizes and apparent viscosity of commercial TPS-stabilized emulsions were larger or higher in acidic environments. At pH 2, the apparent viscosity was the lowest for L-TPS. Commercial TPS emulsions were most stable at pH 6, while the L-TPS-stabilized emulsion was most stable at pH 2. The obtained results revealed that the emulsifying properties of TPS varied and the effects of pH on emulsion characteristics differed, as determined from the molecular mass, macromolecular characteristics, and structure. This research is useful for expanding the application of TPS as a novel food ingredient in emulsions. Full article

This study was aimed at increasing the capacity of fermented Tremella fuciformis extracellular polysaccharides (TEPS) for possible functional food applications. Thus, strain varieties, fermentation parameters and purification conditions, and the in vitro antioxidant activities of purified EPS fractions were investigated. An EPS high-yield strain Tf526 was selected, and the effects of seven independent fermentation factors (time, temperature, initial pH, inoculum size, shaking speed, carbon, and nitrogen source) on the EPS yield were evaluated. By single factor optimization test, yeast extract and glucose were chosen as nitrogen sources and carbon sources, respectively, and with initial pH of 6.0, inoculum size of 8%, shaking speed of 150 rpm, and culture at 25 °C for 72 h, the optimal yield of TEPS reached 0.76 ± 0.03 mg/mL. Additionally, A-722MP resin showed the most efficient decoloration ratio compared to six other tested resins. Furthermore, optimal decoloration parameters of A-722MP resin were obtained as follows: decoloration time of 2 h, resins dosage of 2 g, and temperature of 30 °C. Decoloration ratio, deproteinization ratio, and polysaccharide retention ratio were 62.14 ± 2.3%, 81.21 ± 2.13%, and 73.42 ± 1.96%, respectively. Furthermore, the crude TEPS was extracted and four polysaccharide fractions were isolated and purified as Tf1-a, Tf1-b, Tf2, and Tf3 by the DEAE-Sepharose FF column and the Sephasryl S100 column. In general, the antioxidant activities of the Lf1-a and Lf1-b were lower compared with Vc at the concentration of 0.1 to 3 mg/mL, but the FRAP assay, DPPH scavenging activity, and hydroxyl radical scavenging activity analysis still revealed that Tf1-a and Tf1-b possess significant antioxidant activities in vitro. At the concentration of 3 mg/mL, the reducing power of Lf1-a and Lf1-b reached 0.86 and 0.70, the maximum DPPH radical were 54.23 ± 1.68% and 61.62 ± 2.73%, and the maximum hydroxyl radicals scavenging rates were 58.76 ± 2.58% and 45.81 ± 1.79%, respectively. Moreover, there were significant correlations (r > 0.8) among the selected concentrations and antioxidant activities of TEPS major fractions Tf1-a and Tf1-b. Therefore, it is expected that Tf1-a and Tf1-b polysaccharide fractions from fermented TEPS may serve as active ingredients in functional foods. Full article

In this paper, emulsions stabilized by Tremella fuciformis polysaccharides (TFP) were prepared and the physiochemical properties were assessed. Results showed that the TFP emulsions illustrated the highest emulsifying activity (EAI) and emulsifying stability (ESI) when the concentration of TFP and oil were 0.8% and 10% (wt%). The higher pH value was in favor of the emulsifying properties, while the addition of NaCl impaired the stability, and the greater the concentration, the lower the EAI and ESI. Besides, the emulsifying and rheological properties and stability analysis were evaluated in comparison with gum arabic, pectin, and carboxymethyl cellulose emulsions. It was discovered that TFP illustrated better storage and freeze-thaw stability, which was proved by the result of zeta-potential and particle size. The rheological measurement revealed that all the emulsions behaved as pseudoplastic fluids, while TFP displayed a higher viscosity. Meanwhile, TFP emulsions tended to form a more stable network structure according to the analysis of the parameters obtained from the Herschel–Bulkley model. FTIR spectra suggested that the O-H bond could be destructed without the formation of new covalent bonds during the emulsion preparation. Therefore, this study would be of great importance for the research of emulsions stabilized by TFP as a natural food emulsifier. Full article

The edible fungus Tremella fuciformis was shown to have a high molecular weight (1.87 × 10³ kDa) bioactive polysaccharide, denoted as TFP-F1. Monosaccharide composition and NMR analysis of the polysaccharide and its derivatives indicated it contained fucose (Fucp), xylose (Xylp), mannose (Manp), and glucuronic acid (GlcAp) in a ratio of 0.9:1.0:3.2:1.2. Using IR, NMR, and GC-MS spectroscopic data, the structure of TFP-F1 was elucidated as {→3)-[β-D-GlcAp-(1→2)]-α-D-Manp-(1→3)-α-D-Manp-(1→3)-[α-L-Fucp-(1→2)-β-D-Xylp-(1→2)]-α-D-Manp-(1→}_n, with partial acetylation of C6-OH in mannoses. Furthermore, at a concentration of 1 μg/mL, TFP-F1 was found to stimulate the secretion of TNF-α and IL-6 in J774A.1 macrophage cells in vitro via interaction with toll-like receptor 4 (TLR4). The removal of O-acetyl groups led to the loss of immunomodulatory activities, demonstrating that O-acetyl groups play an essential role in enhancing the production of pro-inflammatory cytokines. Full article