Physicochemical analysis, structural elucidation and bioactivities of a high-molecular-weight polysaccharide from Phellinus igniarius mycelia

Structural characteristics and hypoglycemic activity of a polysaccharide from an edible bolete Phlebopus portentosus

Phlebopus portentosus, a bolete renowned for its exceptional flavor, delightful taste, and pleasant texture, has been reported to exhibit hypoglycemic activity attributed to its polysaccharides. However, the structural characteristics of these polysaccharides and the mechanisms of action remain unclear. In this study, a neutral polysaccharide (PPP-0A) was isolated and purified from its fruiting bodies using DEAE-52 cellulose and Sephacryl S-400 HR propylene dextran gel column chromatography. The structural characteristics of PPP-0A were elucidated at multiple levels, employing SEC-MALLS-RI, GC-MS, IR, methylation analysis, NMR, SEM, and CD. PPP-0A is identified as an α-pyranoside with a molecular weight of 13.2 kDa, comprising galactose, fucose, glucose, mannose, and xylose in the ratios of 62.26:16.96:15.23:4.68:0.87. Methylation and NMR analyses suggest that the backbone of PPP-0A mainly consists of →6)-α-D-Galp-(1→, →2,6)-α-D-Galp-(1→, and →3)-α-D-Glcp-(1→. The branches are formed by α-L-Fucp-(1→ linked to the sugar residue at the O-2 position of →2,6)-α-D-Galp-(1→. Furthermore, we confirmed the potent hypoglycemic activity of PPP-0A through enzyme activity assays, inhibition kinetics, and in vitro insulin resistance experiments using HepG2 cells. This study clearly outlines the structural features of purified polysaccharides from P. portentosus under specific processing conditions, establishing a foundation for further investigation into the structure-activity relationship of these bolete polysaccharides.

A Review on the Extraction, Structural Analysis, and Antitumor Mechanisms of Sanghuangporus Polysaccharides

In recent years, the bioactive compounds extracted from Sanghuangporus, especially polysaccharides, phenols, and triterpenoids, have attracted great interest from people due to their extensive biological activity. Among them, polysaccharides are mainly extracted from the seed bodies, mycelium, and fermentation broth of Sanghuangyuan, exhibiting notable effects including immunomodulation, antitumor properties, and hypoglycemic effects. This article provides a comprehensive review of the extraction process, structural characteristics, and antitumor mechanism of Sanghuangyuan polysaccharides. First, the different extraction methods, such as hot water extraction, enzyme-assisted extraction, and ultrasonic-assisted extraction, are summarized. Then, the structure of the Sanghuangporus polysaccharide is studied in detail. Moreover, the antitumor mechanisms demonstrate significant inhibitory impacts on various malignant tumors, spanning gastric, hepatic, colorectal, breast, and prostate cancers. This groundbreaking revelation is of great significance for both the food and pharmaceutical sectors, presenting innovative pathways for Sanghuangyuan utilization and potentially inducing advancements in product development, treatment modalities, and therapeutic interventions.

Structural characterization and antioxidant activity evaluation of a polysaccharide from pink Auricularia cornea

An acidic polysaccharose (YL-D2N2) was isolated from crude polysaccharides of pink Auricularia cornea and characterized for its structural and antioxidant properties. YL-D2N2 consists of fucose, galactose, glucose, xylose, mannose and glucuronic acid in a molar ratio of 0.85: 1.50: 4.44: 27.52: 46.56: 19.13. It has a number-average molecular weight of about 52.811 kDa and a weight-average molecular weight of about 135.457 kDa. Structural characterization showed that YL-D2N2 consists of nine residues (Xylp-(1→, GlcpA-(1→, →2)-Xylp-(1→, →3)-Galp-(1→, →3)-Manp-(1→, →4)-GlcpA-(1→, →2,3)-Manp-(1→, →3,4)-Glcp-(1→, →3,6)-Manp-(1→), with a backbone of →3)-β-D-Manp-(1→, →2,3)-α-D-Manp-(1→, →3,6)-α-D-Manp-(1 → and side chains containing β-D-Xylp-(1 → and α-D-GlcpA-(1→. Notably, YL-D2N2 exhibits significant radical scavenging activity for superoxide anions, reaching 50.82 ± 0.64 % at a concentration of 3.2 mg/mL. Overall, YL-D2N2 exhibits a unique chemical structure and specialized applications for targeting superoxide anion radicals, providing valuable insights for further exploration of its structure-activity relationship.

Dynamic changes in the gel properties, microbial community, and volatile flavor profile of Spanish mackerel (Scomberomorus niphonius) sausages inoculated with Lactiplantibacillus plantarum CY1-2

Spanish mackerel is an important economic fish species in China, but corruption undermines its overall economic value. Fermentation serves as a crucial technique for preserving perishable fish in developing countries. This study aimed to examine the dynamic changes in the gel properties, physicochemical properties, microbial diversity, and volatile flavor compounds (VFCs) of Spanish mackerel sausages inoculated with Lactiplantibacillus plantarum CY1-2 during fermentation. The correlation between key microorganisms and VFCs was explored using a two-way orthogonal partial least squares analysis. The results showed that the group inoculated with strain CY1-2 exhibited significant improvements compared with the control group after 40 h of fermentation. Specifically, gel strength increased by 207.7%, total free amino acids increased by 37.49%, DPPH and ABTS radical scavenging rates increased by 34.12% and 58.73%, and TVB-N levels decreased by 54.2%, respectively. In addition, using gas chromatography-mass spectrometry, 36 VFCs were detected in fermented sausages, including 9 aldehydes, 9 hydrocarbons, 7 alcohols, 4 acids, 2 ketones, and 5 esters. High-throughput sequencing demonstrated that the bacterial profiles were altered in sausages inoculated with strain CY1-2 during fermentation. Enhydrobacter dominated initially but was quickly replaced by Macrococcus after 8 h of fermentation, while Lactobacillus became the dominant genus after 40 h. Correlation analysis revealed that Lactobacillus and Staphylococcus played important roles in the production of VFCs in the fermented sausages. Notably, Lactobacillus was positively associated with 2-undecanone, pentadecane, and hexanal. This study confirmed that strain CY1-2 inoculation could enable the production of high-quality fermented fish sausages.

Water-Soluble Intracellular Polysaccharides (IPSW-2 to 4) from Phellinus igniarius Mycelia: Fractionation, Structural Elucidation, and Antioxidant Activity

Phellinus igniarius is a medicinal fungus. Nonetheless, research on its water-soluble intracellular polysaccharides (IPSW-2 to 4) fractionation, structural elucidation, and antioxidant activity is limited. In this study, water-soluble intracellular polysaccharides (IPSW-2 to 4) were extracted and fractionated from P. igniarius mycelia, and their antioxidant and structural properties were assessed using GC-FID, GC-MS, FTIR, and NMR spectroscopy (1H and 13C). In the water-eluted P. igniarius polysaccharide fractions (IPS30W, IPS60W, and IPS80W) of anion-exchange chromatography, the polysaccharide content was 79.05%, 68.25%, and 62.06%, with higher yields of 25.07%, 21.38%, and 20.34%, respectively. In contrast, the salt (NaCl) elution fractions (IPS30S1, IPS60S1, IPS60S2, and IPS80S1) of anion-exchange chromatography had lower polysaccharide content and yield. Hence, water elution fractions (IPS30W, IPS60W, and IPS80W) were selected for further purification. After repeated purification using size-exclusion chromatography, IPSW-2 to 4 were obtained with a yield of 8% to 15.83%. The IPSW-2 to IPSW-4 structures were elucidated, and they showed no triple helical conformation. Based on periodate oxidation, Smith degradation, methylation analysis, and 1H and 13C NMR spectroscopy, the primary structures of IPSW-2, IPSW-3, and IPSW-4 were all glucan, with the main chain consisting of (1→6)-α-D-Glcp, (1→3,4)-α-D-Glcp, and (1→3, 6)-α-D-Glcp, with α-D-Glcp as a side chain. Finally, antioxidant analysis showed that IPS30W, IPS60W, and IPS80W were all more capable of scavenging superoxide anions than the polysaccharides of Phyllostachys (13.8%) and floribunda (15.1%) at the same concentration (0.40 mg/mL). This will serve as a guide for the development of functional foods.

Structural analysis of Pleurotus ferulae polysaccharide and its effects on plant fungal disease and plant growth

A novel polysaccharide, named as PFP1-1 (23 kDa), was isolated from the fruiting body of Pleurotus ferulae. Structural analysis revealed that PFP1-1 is primarily composed of mannose, galactose, glucose and fucose, with a molar ratio of 41.50:41.92:4.65:1.93. Infrared spectroscopy analysis showed the presence of characteristic absorption peaks associated with polysaccharides. Further analysis using gas chromatography-mass spectrometry (GC-MS) and Nuclear Magnetic Resonance (NMR) indicated that the polysaccharide mainly composed of → 6) -α-D-Galp- (1 →, → 2,6) -α-D-Galp- (1 → and a small amount of → 4) -α-D-Glcp- (1 →. The branched chain is mainly composed of β-D-Manp- (1 → and α-D-Glcp- (1 → connected at the O-2 position of the sugar residue → 2,6) -α-D-Galp- (1 →. PFP1-1 exhibited significant antifungal activity against Rhizoctonia solani and promoted cucumber plant growth. The mycelial growth inhibition rate of PFP1-1 against R. solani reached 70 %. In pot experiments, cucumber seedlings treated with PFP1-1 demonstrated resistance to R. solani infection and the incidence rate was significantly reduced to 22.92 %. PFP1-1 increased the root length and fresh weight of cucumber seedlings and enhanced the stress and disease resistance of plants by increasing the activities of superoxide dismutase, peroxidase and polyphenol oxidase. In conclusion, the present study provides a theoretical and experimental basis for the application of P. ferulae polysaccharide in promoting plant growth and controlling plant diseases.

Mechanisms of action of fungal polysaccharides and their therapeutic effect

BACKGROUND

The purpose of this article is to discuss the relationship between the therapeutic bioactivity of basidial fungal polysaccharides (BFPs) BFPs and their structural characteristics and conformational features, as well as to characterize the mechanisms of action of BFPs in diseases of various origins.

METHODS

The review was conducted using the PubMed (Medline), Scopus, Web of Science and the Russian Science Citation Index databases. 8645 records were identified, of which 5250 were studies (86 were randomized controlled trials). The period covered is from 1960 to the present. The most significant studies conducted mainly in Southeast Asian countries were selected for the review.

RESULTS

Based on clinical studies, as well as the results obtained on in vivo, in vitro and ex vivo models, it has been proven that BFPs have diverse and highly effective biological activity in the human body in various diseases. The production of BFPs-based vaccines is an innovative strategy from a clinical and biochemical point of view, since as potential immunoprotective and low-toxic biopolymers they have innate immune receptors in the body. Promising results have been obtained in the development of antidiabetic drugs, probiotic, renoprotective and neurodegenerative dietary supplements.

CONCLUSIONS

The biological activity, mechanism of action and specific therapeutic effect of BFPs largely depend on their structural and physicochemical characteristics. BFPs as multifunctional macromolecular complexes with low toxicity and high safety are ideal as new powerful pharmaceuticals for the treatment and prevention of many diseases.

Isolation, purification, and structural elucidation of a water-soluble polysaccharide derived from Phellinus baumii Pilát mycelia

This study involved the successful production of mycelial polysaccharides by optimizing submerged culture conditions of Phellinus baumii Pilát. Then, the investigation focused on the composition and chemical structure of the water-soluble polysaccharide from P. baumii Pilát mycelia (PBMP) by extraction and purification. Specifically, this study indicated that a water-soluble PBMP fraction 1 (PBMP1) was isolated from PBMP. Moreover, this study discovered a PBMP1 isolated from PBMP, which was found to have the monosaccharide compositions comprised of fucose (Fuc), glucose (Glc), and galactose (Gal) despite the absence of proteins. Subsequently, the composition and structure of PBMP1 were characterized using Fourier transform infrared (FT-IR) spectroscopy, periodate oxidation, Smith degradation, methylation reaction, gas chromatography-mass spectrometer (GC-MS), and Nuclear magnetic resonance (NMR). The composition and structure of PBMP1 were characterized in this study, revealing an α-glycosidic bond conformational linkage with 1,4-Glc residues and 1,6-Gal residues forming the backbone. Additionally, a highly branched hetero-polysaccharide was identified with a non-reducing terminus of Fuc containing 1,3,4- and 1,4,6-Glc branching. The findings of this study offer valuable insights and information that can be utilized by researchers, manufacturers, and other stakeholders to advance the field of P. baumii Pilát product development. Moreover, these results have significant implications for future large-scale mass production and functional applications of PBMP1 products.

Extraction, Purification, Structural Characterization, and Antitumor Effects of Water-Soluble Intracellular Polysaccharide (IPSW-1) from Phellinus igniarius Mycelia

Phellinus igniarius is a commonly used Chinese medicine fungus, and its polysaccharide is a valuable bioactive with antioxidant, antiaging, antitumor activities, etc. However, their bioactivities are influenced by their structural and physicochemical properties. Hence, this research isolated and purified homogeneous water-soluble intracellular polysaccharide (IPSW-1) from P. igniarius mycelia. A coherent study of its structural characteristics, conformation, and antitumor mechanisms was evaluated. The results showed IPSW-1 has no triple helical conformation according to the Congo red test. Based on FT-IR, periodate oxidation, Smith degradation, methylation analysis, 1H and 13C NMR spectroscopy data, and IPSW-1 consisted of α-d-glucopyranose (Glcp). The backbone of IPSW-1 consisted primarily of repeating three (1 → 6)-linked α-d-Glcp and one (1 → 3,4)-linked α-d-Glcp, with one terminal α-d-Glcp as side chains of 3-O-connected to the main chain for every four residues. The IPSW-1 had an inhibitory influence on HepG2 cell proliferation and inhibited the migration and invasion ability by down-regulating the expression levels of MMP-7 and RhoA. Moreover, IPSW-1 could inhibit the lysis of autophagosomes to inhibit autophagy and regulate mitochondrial membrane potential and pro-apoptotic protein Bax, which causes the caspase cascade to promote apoptosis, thereby inhibiting the role of tumor cells. These findings show IPSW-1 holds potential as an innovative functional food.

Structural characterization and adjuvant activity of a water soluble polysaccharide from Poria cocos

Adjuvants, as the essential component of vaccines, are crucial in enhancing the magnitude, breadth and durability of immune responses. Unfortunately, commonly used Alum adjuvants predominantly provoke humoral immune response, but fail to evoke cellular immune response, which is crucial for the prevention of various chronic infectious diseases and cancers. Thus, it is necessary to develop effective adjuvants to simultaneously induce humoral and cellular immune response. In this work, we obtained a water soluble polysaccharide isolated and purified from Poria cocos, named as PCP, and explored the possibility of PCP as a vaccine adjuvant. The PCP, with Mw of 20.112 kDa, primarily consisted of →6)-α-D-Galp-(1→, with a small amount of →3)-β-D-Glcp-(1 → and →4)-β-D-Glcp-(1→. Our results demonstrated that the PCP promoted the activation of dendritic cells (DCs) and macrophages in vitro. As the adjuvant to ovalbumin, the PCP facilitated the activation of DCs in lymph nodes, and evoked strong antibody response with a combination of Th1 and Th2 immune responses. Moreover, compared to Alum adjuvant, the PCP markedly induced a potent cellular response, especially the cytotoxic T lymphocytes response. Therefore, we confirmed that the PCP has great potential to be an available adjuvant for simultaneously inducing humoral and cellular immune responses.

Isolation Techniques, Structural Characteristics, and Pharmacological Effects of Phellinus Polysaccharides: A Review

Phellinus is a precious perennial medicinal fungus. Its polysaccharides are important bioactive components, and their chemical composition is complex. The polysaccharides are mainly extracted from the fruiting body and mycelium. The yield of the polysaccharides is dependent on the extraction method. They have many pharmacological activities, such as antitumor, immunomodulatory, antioxidant, hypoglycemic, anti-inflammatory, etc. They are also reported to show minor toxic and side effects. Many studies have reported the anticancer activity of Phellinus polysaccharides. This review paper provides a comprehensive examination of the current methodologies for the extraction and purification of Phellinus polysaccharides. Additionally, it delves into the structural characteristics, pharmacological activities, and mechanisms of action of these polysaccharides. The primary aim of this review is to offer a valuable resource for researchers, facilitating further studies on Phellinus polysaccharides and their potential applications.

Physicochemical characterization, digestion profile and gut microbiota regulation activity of intracellular polysaccharides from Chlorella zofingiensis

A number of studies have shown that the polysaccharides from microalgae exhibit diverse biological activities, however, little is known about their digestibility and impact on human gut microbiota. In this study, a simulating digestion and fermentation system were established to investigate the digestibility and fermentation of intracellular polysaccharides from Chlorella zofingiensis (CZIP-S3). The results indicated that CZIP-S3 is a macromolecular polysaccharide composed of mannose, glucose, galactose and rhamnose, consisting of a main chain and two branched repeating units. CZIP-S3 could not be digested in the upper gastrointestinal tract. However, CZIP-S3 could be metabolized into smaller molecules by the gut microbiota. The pH values continuously decrease during fermentation, whereas, the amount of short-chain fatty acids steadily increase. Furthermore, CZIP-S3 could modulate the composition of gut microbiota, via lowering the ratio of Firmicutes/Bacteroidetes and increasing the relative abundance of Bacteroides, Bifidobacterium and Akkermansia. The data suggested that CZIP-S3 could potentially be used as an ingredient for functional foods or prebiotics to improve human health by promoting the relative abundances of beneficial bacteria.

A Neutral Polysaccharide from Spores of Ophiocordyceps gracilis Regulates Oxidative Stress via NRF2/FNIP1 Pathway

Ophiocordyceps gracilis (O. gracilis) is a parasitic fungus used in traditional Chinese medicine and functional foods. In this study, a neutral heteropolysaccharide (GSP-1a) was isolated from spores of O. gracilis, and its structure and antioxidant capacities were investigated. GSP-1a was found to have a molecular weight of 72.8 kDa and primarily consisted of mannose (42.28%), galactose (35.7%), and glucose (22.02%). The backbone of GSP-1a was composed of various sugar residues, including →6)-α-D-Manp-(1→, →2,6)-α-D-Manp-(1→, →2,4,6)-α-D-Manp-(1→, →6)-α-D-Glcp-(1→, and →3,6)-α-D-Glcp-(1→, with some branches consisting of →6)-α-D-Manp-(1→ and α-D-Gal-(1→. In vitro, antioxidant activity assays demonstrated that GSP-1a exhibited scavenging effects on hydroxyl radical (•OH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS•+), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•). Moreover, GSP-1a was found to alleviate H2O2-induced oxidative stress in HepG2 cells by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activities of superoxide dismutase (SOD). Furthermore, GSP-1a upregulated the mRNA expression of antioxidant enzymes such as Ho-1, Gclm, and Nqo1, and regulated the NRF2/KEAP1 and FNIP1/FEM1B pathways. The findings elucidated the structural types of GSP-1a and provided a reliable theoretical basis for its usage as a natural antioxidant in functional foods or medicine.

Extraction, purification, structural characterization and biological activity of polysaccharides from Fritillaria: A review

Fritillaria is a traditional Chinese medicine(TCM) with a history of thousands of years. Fritillaria always contain saponins, alkaloids, amino acids, flavones, and polysaccharides. Among them, Fritillaria polysaccharide has a variety of biological activities. Its anti-inflammatory and antiaging activities are new study hotspots. The extraction, purification, quantitative determination, monosaccharide composition, and biological activity of Fritillaria polysaccharides have been examined for several years in an attempt to identify the active components and understand the pharmacological process. In this review, ample original publications related to the distribution, extraction, purification, quantitative determination, monosaccharide composition and biological activities of Fritillaria until 2023 were searched and collected by using various literature databases. Databases included the China National Knowledge Infrastructure, VIP database, Wan Fang database, PubMed, Elsevier, Springer, Science Direct, Google Scholar and Web of Science database, as well as the classic Chinese medical books and PhD and MSc theses. The properties and outcomes of various extractions, purifications, quantitative determination methods, monosaccharide compositions, and biological activities of Fritillaria polysaccharides are discussed here. Additionally, we summarize the research potential of Fritillaria polysaccharide and identify promising research direction candidates.

Immune-enhancing activity of polysaccharides and flavonoids derived from Phellinus igniarius YASH1

Introduction: Phellinus igniarius (P. igniarius) (Sanghuang) is a widely used traditional Chinese medicine fungus, and its natural products have great potential for clinical application in immune enhancement. This study aimed to explore the immune-enhancing activity and underlying mechanisms of the polysaccharides and flavonoids derived from Phellinus igniarius (P. igniarius) and to provide a theoretical and experimental basis for the development of novel drugs. Methods: Wild P. igniarius YASH1 from the Loess Plateau in Yan'an region was collected, and polysaccharides and total flavonoids were extracted, isolated and identified from mycelium and sporophore. In vitro antioxidant activity was detected through the scavenging activity of hydroxyl radicals and total antioxidant capacity. Cell Counting Kit-8 and trypan blue detection kit were used to detect the effect of extract polysaccharides and flavonoids on the proliferation and phagocytosis ability of immune cells. To assess the effect of the drugs on cytokine secretion by immune cells and immune recovery in immunocompromised mice, the expression of interleukin (IL)-2, IL-6, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α were examined at the cellular and animal levels. The species composition, abundance of gut microbiota and the altered content of short-chain fatty acids in the feces were analyzed to elucidate the possible mechanisms of drugs by 16S ribosomal RNA (rRNA) amplifiers sequencing and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Both polysaccharides and flavonoids derived from mycelium or sporophore had antioxidant activity and may stimulate the expression and secretion of IL-2, IL-6, and IFN-γ in immune cells while inhibiting TNF-α expression and secretion and increasing IL-2, IL-6, and IFN- γ expression levels in mice. Furthermore, polysaccharides and flavonoids from mycelium and sporophore showed different effects on the metabolic response of intestinal short-chain fatty acids (SCFAs) in mice, and the use of these drugs remarkably changed the species composition and abundance of intestinal flora in mice. Discussion: Polysaccharides and flavonoids from P. igniarius YASH1 mycelium and sporophore have in vitro antioxidant activity, and they affect the promotion of cell proliferation, stimulation of IL-2, IL-6, and IFN-γ secretion, and inhibition of TNF-α expression in immune cells. Polysaccharides and flavonoids from P. igniarius YASH1 may enhance immunity in immunocompromised mice and remarkably affect the intestinal flora and content of SCFAs.

Identification of galacturonic acid-rich polysaccharide with intestinal immune system modulating activity via Peyer's patch from postbiotics of Phellinus linteus mycelial submerged culture

Interests in the development and exploration of industrial applications of medicinal mushrooms as postbiotics have lately increased. We recently reported the potential use of Phellinus linteus mycelial-containing whole culture extract (PLME) prepared by submerged cultivation as a postbiotic that promotes immune system activation. Here, we aimed to isolate and structurally elucidate the active ingredients in PLME by activity-guided fractionation. The intestinal immunostimulatory activity was evaluated by bone marrow (BM) cell proliferation activity and related cytokine production in C3H-HeN mouse-derived Peyer's patch (PP) cells treated with polysaccharide fractions. The initially crude polysaccharide (PLME-CP) of PLME prepared using ethanol precipitation was further fractionated into four fractions (PLME-CP-0 to -III) by anion-exchange column chromatography. BM cell proliferation and cytokine production of PLME-CP-III were significantly improved compared to those of PLME-CP. PLME-CP-III was then fractionated into PLME-CP-III-1 and PLME-CP-III-2 by gel filtration chromatography. Based on the molecular weight distribution, monosaccharide, and glycosyl linkage analyses, PLME-CP-III-1 was revealed as a novel galacturonic acid-rich acidic polysaccharide and further shown to play an important role in facilitating PP-mediated intestinal immunostimulatory activity. This is the first study demonstrating the structural characteristics of a novel intestinal immune system modulating acidic polysaccharide from P. linteus mycelium-containing whole culture broth postbiotics.

Bioactive Compounds from Medicinal Mushrooms

Research progress of active compounds and biological activities of medicinal mushroom-Ganoderma spp., Hericium spp., Phellinus spp., and Cordyceps spp. were summarized systematically. The main active compounds of medicinal mushrooms included are polysaccharides, proteins, triterpenes, meroterpenoids, polyphenols and nitrogen-containing compounds. The biological activities of the compounds cover immunomodulatory activity, antitumor activity, hypoglycemic activity, hepatoprotective activity, and activity of regulation of intellectual flora.

Enhancement of triterpene production via in situ extractive fermentation of Sanghuangporus vaninii YC-1

There have been many studies on the activities and polysaccharide production of Sanghuangporus vaninii. However, few studies have looked at triterpene production from S. vaninii using liquid-state fermentation. A method for enhancing the production of triterpenes by in situ extractive fermentation (ISEF) was studied. Eight solvents were investigated as extractants for triterpene production in the ISEF system. The results showed that using vegetable oil as an extractant significantly increased the yield of total triterpenes and biomass of S. vaninii YC-1, reaching 18.98 ± 0.71 and 44.67 ± 2.21 g/L, respectively. In 5 L fermenter experiments, the added vegetable oil improved the dissolved oxygen condition of the fermentation broth and promoted the growth of S. vaninii YC-1. Furthermore, adding vegetable oil increased the expression of fatty acid synthesis-related genes such as FAD2 and SCD, thereby increasing the synthesis of unsaturated fatty acids in the cell membrane of S. vaninii YC-1. Therefore, the cell membrane permeability of S. vaninii YC-1 increased by 19%. Our results indicated that vegetable oil increased the permeability of S. vaninii YC-1 cell membranes to promote the production of total triterpenes. The use of vegetable oil as an extractant was thus effective in increasing the yield of triterpenes in the ISEF system.

Structural characterization of a new high molecular weight polysaccharide from jujube fruit

From Ziziphus Jujuba cv. Muzao fruit, a new polysaccharide (PZMP3-1) with high molecular weight was isolated. Constructional characterization revealed that PZMP3-1 comprized 2.56 rhamnose, 7.70 arabinoses, 3.73 galactose, and 6.73 galactose, and it has a 241 kDa average molecular weight. The principal structural components of PZMP3-1 were 1,2,4 and 1,4-linked GalpA, 1,4-linked Galp, 1,3 and 1,5-linked Araf, and 1-linked Rhap based on methylation and nuclear magnetic resonance spectroscopy (NMR) analyses. X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM) structural analysis of PZMP3-1 revealed a tangled and branching pattern. Overall, these structural results suggested that PZMP3-1 could have unique bioactivities and be widely used in nutritional supplements.

Preparation and Antioxidant Activity In Vitro of Fermented Tremella fuciformis Extracellular Polysaccharides

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.

Current advances and potential trends of the polysaccharides derived from medicinal mushrooms sanghuang

For thousands of years, sanghuang is distinctive as a general designation for a group of precious and rare Chinese medicinal mushrooms. Numerous investigations have revealed that polysaccharide is one of the important biological active ingredients of sanghuang with various excellent biological activities, including antioxidant, anti-aging, anti-tumor, immunomodulatory, anti-inflammatory, anti-diabetic, hepatoprotective, and anti-microbial functionalities. For the past two decades, preparation, structural characterization, and reliable bioactivities of the polysaccharides from fruiting bodies, cultured mycelia, and fermentation broth of sanghuang have been arousing extensive interest, and particularly, different strains, sources, and isolation protocols might result in obvious discrepancies in structural features and bioactivities. Therefore, this review summarizes the recent reports on preparation strategies, structural features, bioactivities, and structure-activity relationships of sanghuang polysaccharides, which will enrich the knowledge on the values of natural sanghuang polysaccharides and support their further development and utilization as therapeutic agents, vaccines, and functional foods in tonic and clinical treatment.

Structural diversity and bioactivity of polysaccharides from medicinal mushroom Phellinus spp.: A review

Phellinus spp., an important medicinal fungus mushroom extensively cultivated and consumed in East Asia for over 2000 years, is traditionally considered a precious food supplement and medicinal ingredient. Published studies showed that the polysaccharides are major bioactive macromolecules from Phellinus spp. (PPs) with multiple health-promoting effects, including immunomodulatory, anti-cancer, anti-inflammatory, hepatoprotective, hypoglycemic, hypolipidemic, antioxidant, and other bioactivities. Although the polysaccharides extracted from the fruiting body, mycelium, and fermentation broth of Phellinus spp. have been extensively studied for the extraction and purification methods, structural characteristics, and pharmacological activities, the knowledge for their structures and bioactivity relationship, toxicologic effects, and pharmacokinetic profile is limited. This review systematically summarizes the recent progress in the isolation and purification, chemical structures, bioactivities, and the underlying mechanisms of PPs. Information from this review provides insights into the further development of polysaccharides from PPs as therapeutic agents and functional foods.

A new GlcNAc-containing polysaccharide from Morchella importuna fruiting bodies: Structural characterization and immunomodulatory activities in vitro and in vivo

This study investigated the purification and characterization of a new immunomodulatory GlcNAc-containing polysaccharide (MIPB70-1) from Morchella importuna with molecular weights of 20.6 kDa. Structural analysis indicated that MIPB70-1 was composed of GlcNAc:Gal:Glc:Man with molar ratios of 1.00:7.16:5.54:5.61, and its primary structure was characterized as a repeating unit consisting of →6)-α-D-Glcp-(1→, α-D-GlcpNAc-(1→, α-D-Galp-(1→, β-D-Glcp-(1→, →6)-α-D-Manp-(1→, →4)-α-D-GlcpNAc-(1→, →4)-β-D-Glcp-(1→, →3,6)-α-D-Manp-(1→, →2)-α-D-Galp-(1→, →2,3,6)-α-D-Manp-(1→. Immunological assays indicated that MIPB70-1 enhanced the phagocytic function and promoted the secretion of nitric oxide (NO) as well as cytokines through targeting Toll-like receptor 4 (TLR4) on macrophage membrane and activating the downstream signaling pathways in RAW 264.7 cells. MIPB70-1 regulated mouse immunity to counteract the immune damage caused by the chemotherapy drug cyclophosphamide (CTX) in vivo. Furthermore, MIPB70-1 enhanced the anti-tumor activity of doxorubicin (DOX) and inhibited the growth of tumors, by immunomodulation in the orthotopic murine model of 4T1 breast cancer. These results demonstrate the potential of this GlcNAc-containing polysaccharide as an immune enhancer.

Selected Species of the Genus Phellinus - Chemical Composition, Biological Activity, and Medicinal Applications

This study presents the current knowledge on chemical composition, biological activity, and possible medicinal applications of Phellinus igniarius, Phellinus pini, Phellinus pomaceus, and Phellinus robustus. These inedible arboreal species are phytopathogens that cause the enzymatic decomposition of wood. These species belong to the medicinal mushrooms and have been known for centuries in the traditional medicine of the Far East. They have been used as an effective remedy for stomach and intestinal ailments, diarrhea, and hemorrhages. Mycochemical studies have proved the presence of polysaccharides, phenolic compounds, and terpenoids. These compounds show biological activities such as anticancer, antioxidant, antiangiogenic, and antiviral. Research studies conducted using modern analytical methods have advanced the knowledge on the potential therapeutic use of compounds isolated not only from the fruiting bodies but also from biomass obtained with in vitro biotechnological methods.

A polysaccharide of PFP-1 from Pleurotus geesteranus attenuates alcoholic liver diseases via Nrf2 and NF-κB signaling pathways

A polysaccharide named PFP-1 was isolated from the Pleurotus geesteranus fruiting body, and potential investigations on ameliorating oxidative stress and liver injury against alcoholic liver disease (ALD) were performed in mice. The animal studies demonstrated that PFP-1 had hepatoprotective effects by improving hepatocellular histopathology, modulating alcohol metabolisms and restoring the serum lipid levels. Besides, PFP-1 could attenuate oxidative stress and inflammatory responses by activating the Nrf2-mediated signal pathways and regulating the TLR4-mediated NF-κB signal pathways. The characterization indicated that PFP-1 was a typical pyranose-polysaccharide in a triple-helical conformation, which was linked by t-β-Glcp, 1,6-α-Glcp and 1,2,6-α-Galp. And the characteristic properties of higher water solubility and appropriate molecular weights contributed to the superior bioactivities. The results demonstrated that PFP-1 could be used as a supplement for alleviating alcohol-induced liver damage.

Purification of polysaccharides from Phellinus linteus by using an aqueous two-phase system and evaluation of the physicochemical and antioxidant properties of polysaccharides in vitro

In this study, Phellinus linteus polysaccharides (PLPS) and proteins were simultaneously separated from P. linteus mycelia by using an aqueous two-phase system (ATPS) based on choline chloride ([Chol]Cl)/K₂HPO₄, and the physicochemical and antioxidant properties of PLPS after ATPS extraction were evaluated. Results demonstrated that the maximal extraction efficiencies of 68.53% ± 0.29% PLPS and 82.37% ± 0.41% proteins were obtained when the cholinium-based ATPS contained 68.9% K₂HPO₄, 20% [Chol]Cl, 10.0 mg mL^-1 crude water extract (1.0 mL), and distilled water (4.0 mL) at shaking time and temperature of 30 min and 21.2 °C, respectively. Compared with C-PLPS obtained using traditional ethanol precipitation and isolation protocols, PLPS had higher carbohydrate content (63.58% ± 1.12%), lower molecular weight (15.2 kDa, 80%), different monosaccharide compositions, and showed similar preliminary structural characterizations. Moreover, PLPS exhibited more evident scavenging effects on free radicals and in vitro antioxidant activities than C-PLPS. Therefore, the method of [Chol]Cl/K₂HPO₄ ATPS can be developed as an effective strategy for the separation/purification of highly bioactive polysaccharides.

Isolation, purification, structural characteristics, pharmacological activities, and combined action of Hedyotis diffusa polysaccharides: A review

Hedyotis diffusa polysaccharides, as the main component and an important bioactive substance of Hedyotis diffusa, are effective immunomodulators with various pharmacological activities, including antitumour, anti-inflammatory, antioxidant, anti-fatigue and immunity-enhancing activities. The total polysaccharides extracted from Hedyotis diffusa and Scutellaria barbata have great effects in treating liver cancer, gastric cancer, rectal cancer, glioma and nasopharyngeal carcinoma. Moreover, different materials and extraction methods result in differences in the structure and bioactivity of Hedyotis diffusa polysaccharides. Therefore, this paper summarizes the isolation, purification, structural characteristics, pharmacological activities, and combined action of Hedyotis diffusa polysaccharides to provide a reference for further study.

Structural characteristics and immunostimulatory activities of a new polysaccharide from Dendrobium fimbriatum Hook

A new polysaccharide (cDFP-W1) with high immunostimulatory activities was isolated from the stems of Dendrobium fimbriatum Hook. The analysis of the physicochemical properties showed that cDFP-W1 consisted of mannose and glucose in a molar ratio of 1 : 3.84, and its relative molecular weight was 4.0 × 10⁴ Da. Structural analysis implied that the linear backbone of cDFP-W1 was composed of α-1,4-d-Glcp, β-1,4-d-Manp, 3-O-acetyl-α-1,4-d-Glcp and α-1,4,6-d-Glcp, and its branches were the terminal β-d-Manp that was attached to the C-6 position of α-1,4,6-d-Glcp. An in vivo immunostimulatory assay exhibited that cDFP-W1 at 200 mg kg^-1 could significantly increase the proportions of CD4⁺ T-cell subpopulations, B cells, natural killer cells and dendritic cells, decrease the proportion of CD8⁺ T-cell subpopulations, and upregulate the percentage of activated macrophages (p < 0.01) in the spleen of mice. An in vitro immunostimulatory assay revealed that cDFP-W1 could effectively promote the proliferation of spleen lymphocytes, enhance the proliferation and phagocytosis of macrophage RAW264.7 cells, and stimulate the mRNA expression and extracellular release of NO, TNF-α and IL-1β of RAW264.7 cells. The western blot experiment suggested that the immunostimulatory activities of cDFP-W1 were closely related to the activation of MAPKs, NF-κB and PI3K/Akt signaling pathways.

The phytochemistry and pharmacology of medicinal fungi of the genus Phellinus: a review

Phellinus Quél is one of the largest genera of Hymenochaetaceae, which is comprised of about 220 species. Most Phellinus macro-fungi are perennial lignicolous mushrooms, which are widely distributed on Earth. Some Phellinus fungi are historically recorded as traditional medicines used to treat various diseases in eastern Asian countries, especially China, Japan and Korean. Previous phytochemical studies have revealed that Phellinus fungi produce diverse secondary metabolites, which mainly contain polysaccharides, flavones, coumarins, terpenes, steroids, and styrylpyranones. Pharmacological documents have demonstrated that Phellinus mushrooms and their compounds have a variety of bioactivities, such as anti-tumor, immunomodulation, anti-oxidative and anti-inflammation, anti-diabetes, neuro-protection, and anti-viral effects. This review surveys the literature reporting the isolation, characterization, and bioactivities of secondary metabolites from the fungi of the genus Phellinus, focusing on studies published in the literature up to April 2020. Herein, a total of more than 300 compounds from 13 Phellinus species and their isolation, characterization, chemistry, pharmacological activities, and relevant molecular mechanisms are comprehensively summarized.

Structure and hypoglycemic activity of a novel exopolysaccharide of Cordyceps militaris

A novel neutral exopolysaccharide (EPS-III) was isolated from culture broth of Cordyceps militaris (C. militaris). The EPS-III was a homogeneous polysaccharide with M_w of 1.56 × 10³ kDa. The yield of EPS-III from culture broth was 123.2 ± 3.1 mg/L and the sugar content was 93.32 ± 0.87%. The backbone of EPS-III was mainly consisted of →4)-α-D-Galp-(1→, while →3, 6)-α-D-Manp-(1→, →4)-α-D-Manp-(1→, →3)-β-D-Galp-(1→ and →3)-α-D-Glcp-(1→ were distributed in the backbone or in the branch chains. The EPS-III had helix structure when dissolved in weak alkaline solution. It also had branched and intertwined form on the surface. The inhibition of α-glucosidase significantly increased as the increase of purity of exopolysaccharides. The EPS-III had effective inhibition on the α-glucosidase with dose-effect relationship. Besides, the results of hypoglycemic activity analysis in vivo indicated that EPS-III can alleviate weight loss, reduce plasma glucose concentration, improve glucose tolerance, protect immune organs and repair dyslipidemia to relieve diabetes in STZ-induced diabetic mice. The manuscript first studied the hypoglycemic activity of exopolysaccharide of by C. militaris, proving and promoting the application value of culture broth. The structure characterization of EPS-III laid experimental foundations on the exploration of structure-activity relationship.

Polysaccharide from Pleurotus nebrodensis: Physicochemical, structural characterization and in vitro fermentation characteristics

A high Mw (5012 kDa) polysaccharide (PNPS) from the fruiting body of Pleurotus nebrodensis was isolated using water extraction followed by ethanol precipitation. The structural characteristics and in vitro fermentation behaviors of this polysaccharide was investigated. Chemical composition analysis showed the total sugar content of PNPS was up to 97.20 ± 1.80 wt%. Monosaccharide composition analysis showed PNPS contained mainly glucose (89.22 ± 5.70 mol%) while small percentage of mannose (5.60 ± 0.74 mol%) and galactose (5.18 ± 0.33 mol%) were also detected. According to the linkage pattern analysis (methylation analysis), PNPS comprised mainly 4-β-D-Glcp (58.90 mol%), while other residues including α-D-Glcp, 6-α-D-Galp, 3,6-α-D-Manp, 3-β-D-Glcp and 6-α-D-Glcp were detected with a comparable amount. Combined with results from 1D and 2D NMR spectrum, a proposed structure of PNPS was presented. In vitro fermentation of PNPS by gut microbiota showed total SCFA production of all treatment groups was higher than negative control group (NC) significantly (p < 0.05) after 48 h of fermentation. The formation of SCFAs was mainly acetic acid, followed by propionic acid and butyric acid, and the pH was decreased from 6.95 to 4.70. After 72 h, the total sugar content decreased from 5.813 ± 0.87 mg/L to 0.23 ± 0.065 mg/L, and the molecular weight of PNPS decreased.

Acetylated Polysaccharides From Pleurotus geesteranus Alleviate Lung Injury Via Regulating NF-κB Signal Pathway

The present work investigated the anti-inflammatory, antioxidant, and lung protection effects of acetylated Pleurotus geesteranus polysaccharides (AcPPS) on acute lung injury (ALI) mice. The acetylation of AcPPS was successfully shown by the peaks of 1737 cm⁻¹ and 1249 cm⁻¹ by FTIR. The animal experiments demonstrated that lung damage can be induced by zymosan. However, the supplementation of AcPPS had potential effects on reducing lung index, remitting inflammatory symptoms (TNF-α, IL-1β, and IL-6), inhibiting NF-κB signal pathway based on up-regulating the level of IκBα and down-regulating p-IκBα level by Western blotting and immunofluorescence assay, preventing oxidative stress (ROS, SOD, GSH-Px, CAT, T-AOC, and MDA), reducing lipid accumulation (TC, TG, LDL-C, HDL-C, and VLDL-C), and alleviating lung functions by histopathologic observation. These results demonstrated that AcPPS might be suitable for natural food for prevention or remission in ALI.

Laser Mutagenesis of Phellinus igniarius Protoplasts for the Selective Breeding of Strains with High Laccase Activity

Phellinus igniarius is a medicinal fungus that utilizes lignin as a nutrient substrate. This fungus has a weak lignin degradation ability and, as a result, a slow growth rate. Laccases are crucial enzymes for lignin degradation in P. igniarius, and thus, the cultivation of strains with high laccase activity is expected to increase the growth rate of P. igniarius. To generate P. igniarius strains with high laccase activity, we performed laser mutagenesis of P. igniarius protoplasts and screened for mutants with high laccase activity. Our results showed that the laser power density and P. igniarius protoplast survival rate exhibited a power-function relationship. The power density threshold value between lethality and growth promotion was 0.24 mW/mm². Mutagenesis was carried out using a laser beam diameter of 3 mm and an irradiation period of 40 min. After five generations of selection, we identified a high laccase activity strain, termed SJZ2. The laccase activity in SJZ2 during 4 h of fermentation was increased by 36.84% in comparison with the control and ranged from 0.20216 to 0.27664 U. The Km and Vmax of the laccase produced by SJZ2 were 0.21 mmol/mL and 0.53 mmol/L/min, respectively. This study demonstrated the feasibility of laser mutagenesis of P. igniarius protoplasts for the selection of high laccase activity. This study characterized the key factors in the laser mutagenesis process of P. igniarius protoplasts and provided a reference for the application of lasers in biological mutagenesis. Future studies should evaluate the bioactive functionality and stability of this novel strain of P. igniarius, particularly the organoleptic and medical characteristics of the fruiting bodies.

Structural characterization and determination of biological activities for different polysaccharides extracted from tree mushroom species

Chemical composition and structural characterization of polysaccharides of Fomes fomentarius (FF), Fuscoporia torulosa, Ganoderma adspersum, Ganoderma applanatum (GAP), Ganoderma lucidum, Phellinus igniarius, Pleurotus ostreatus (PO), and Porodaedalea pini (PP) tree mushrooms with antioxidant and anticholinesterase activities were determined in this research. Total carbohydrate contents of the polysaccharides were ranged between 65.06 ± 6.76 and 88.27 ± 5.15 µg/mg and total protein contents were ranged between 3.18 ± 0.72 and 6.56 ± 1.25 µg/mg. Galactose, glucose, and mannose were identified as major monosaccharides in all polysaccharides using gas chromatography-mass spectrometry. FT-IR analysis showed the characteristic peaks of the polysaccharides and high performance liquid chromatography-diode array detection was used to determine the molecular weight of the polysaccharides. In β-carotene-linoleic acid assay FF (IC₅₀ : 2.55 ± 0.40 µg/ml) displayed the highest antioxidant activity, whereas GAP indicated the highest antioxidant activity in cupric reducing antioxidant capacity (A_0.50 :59.90 ± 0.53 μg/ml), ABTS^•+ (IC₅₀ : 16.62 ± 0.31 μg/ml), and DPPH^• (IC₅₀ : 45.58 ± 0.21 μg/ml) assays. In cholinesterase inhibitory activity test, PO (56.31±0.0.74%) showed significant inhibitory activity against butyrylcholinesterase enzyme. PRACTICAL APPLICATIONS: Polysaccharides from mushrooms are the major class of bioactive compounds with various biological activities. Several studies were performed on the biological activity of the polysaccharide extracts from different mushrooms. However, to our knowledge, this is the first report on the chemical composition, structural characterization, antioxidant, and anticholinesterase activities of extracted polysaccharides from studied mushrooms in detail. This investigation shows that polysaccharide extracts obtained from tree mushrooms show a significant bioactivity and these polysaccharides might be used as bioactive natural sources in the pharmaceutical, food, and cosmetic industries.