Isolation, Purification, and Structural Features of a Polysaccharide fromPhellinus linteusand Its Hypoglycemic Effect in Alloxan-Induced Diabetic Mice

New insights into signaling pathways of cancer prevention effects of polysaccharides from edible and medicinal mushrooms

BACKGROUND

Despite extensive efforts, empirical techniques have yielded limited progress in finding effective anticancer medications, with chemotherapy drugs often associated with drug resistance and serious side effects. Thus, there is a pressing need for novel agents with minimal adverse effects. Natural substances, widely used in treating various illnesses, including cancer, offer promising alternatives. Among these, mushrooms, rich in low molecular weight secondary metabolites, polysaccharides, and polysaccharide-protein complexes, have gained attention for their potential anticancer properties.

RESULTS

Mushroom polysaccharides have been found to impede oncogenesis and tumor metastasis by directly inhibiting tumor cell growth and indirectly enhancing immune system functions. These polysaccharides engage with numerous cell signaling pathways that influence cancer development and progression. They affect pathways that control cell survival, growth, and differentiation, and they also play a role in adjusting the tumor immune microenvironment.

CONCLUSION

This review highlights the potential of mushroom polysaccharides as promising anticancer agents due to their ability to modulate cell signaling pathways crucial for cancer development. Understanding the mechanisms underlying their effects on these pathways is essential for harnessing their therapeutic potential and developing novel strategies for cancer treatment.

A review on the cultivation, bioactive compounds, health-promoting factors and clinical trials of medicinal mushrooms Taiwanofungus camphoratus, Inonotus obliquus and Tropicoporus linteus

Medicinal mushrooms, such as Taiwanofungus camphoratus, Inonotus obliquus, and Tropicoporus linteus, have been used in traditional medicine for therapeutic purposes and promotion of overall health in China and many East Asian countries for centuries. Modern pharmacological studies have demonstrated the large amounts of bioactive constituents (such as polysaccharides, triterpenoids, and phenolic compounds) available in these medicinal mushrooms and their potential therapeutic properties. Due to the rising demand for the health-promoting medicinal mushrooms, various cultivation methods have been explored to combat over-harvesting of the fungi. Evidence of the robust pharmacological properties, including their anticancer, hypoglycemic, hypolipidemic, antioxidant, and antiviral activities, have been provided in various studies, where the health-benefiting properties of the medicinal fungi have been further proven through numerous clinical trials. In this review, the cultivation methods, available bioactive constituents, therapeutic properties, and potential uses of T. camphoratus, I. obliquus and T. linteus are explored.

Mushrooms and Fungi and Their Biological Compounds with Antidiabetic Activity: A Review

Mushrooms have been used by humans for centuries as food and medicine because they have been shown to affect certain diseases. Mushrooms for medicinal purposes have been consumed in the form of extracts and/or biomass of the mycelium or fruiting body. The beneficial health effects of mushrooms are due to their content of bioactive compounds (polysaccharides, proteins, ergosterol, lectins, etc.). On the other hand, diabetes is one of the metabolic diseases that affects the population worldwide, characterized by hyperglycemia that involves a defective metabolism of insulin, a hormone secreted by β cells and that mainly stimulates glucose absorption by the cells. However, it also affects the metabolism of carbohydrates, fats and proteins; poor control of this disease leads to serious damage to eyesight, kidneys, bones, heart, skin, blood vessels, nerves, etc. It has been reported that the consumption of some mushrooms helps control and treat diabetes, since among other actions, they promote the secretion of insulin by the pancreas, help reduce blood glucose and have α-glucosidase inhibitory activity which improves glucose uptake by cells, which are effects that prescription medications have for patients with diabetes. In that sense, this manuscript shows a review of scientific studies that support the abilities of some mushrooms to be used in the control and/or treatment of diabetes.

Polysaccharides from natural resource: ameliorate type 2 diabetes mellitus via regulation of oxidative stress network

Diabetes mellitus (DM) is a group of metabolic diseases characterized by hyperglycemia that can occur in children, adults, elderly people, and pregnant women. Oxidative stress is a significant adverse factor in the pathogenesis of DM, especially type 2 diabetes mellitus (T2DM), and metabolic syndrome. Natural polysaccharides are macromolecular compounds widely distributed in nature. Some polysaccharides derived from edible plants and microorganisms were reported as early as 10 years ago. However, the structural characterization of polysaccharides and their therapeutic mechanisms in diabetes are relatively shallow, limiting the application of polysaccharides. With further research, more natural polysaccharides have been reported to have antioxidant activity and therapeutic effects in diabetes, including plant polysaccharides, microbial polysaccharides, and polysaccharides from marine organisms and animals. Therefore, this paper summarizes the natural polysaccharides that have therapeutic potential for diabetes in the past 5 years, elucidating their pharmacological mechanisms and identified primary structures. It is expected to provide some reference for the application of polysaccharides, and provide a valuable resource for the development of new diabetic drugs.

Study on Extraction, Physicochemical Properties, and Bacterio-Static Activity of Polysaccharides from Phellinus linteus

We optimized an ultrasound-assisted extraction process of Phellinus linteus mycelium polysaccharides (PLPs) and studied their monosaccharide composition and bacteriostatic properties. Based on a single-factor experiment, a three-factor, three-level Box-Behnken design was used to optimize the ultrasound-assisted extraction process of PLP, using the yield of PLP as the index. The chemical composition and monosaccharide composition of PLP were determined by chemical analysis and HPLC analysis, respectively. Microscopic morphological analysis of the surface of PLP was performed via swept-surface electron microscopy. The bacteriostatic properties of PLP were determined using the spectrophotometric turbidimetric method. The results showed that the best extraction process of PLP with ultrasonic assistance achieved a result of 1:42 g/mL. In this method, the ultrasonic temperature was 60 °C, ultrasonic extraction was performed for 20 min, and the yield of PLP was 12.98%. The monosaccharide composition of PLP mainly contains glucose (Glc), mannose (Man), galactose (Gal), and glucuronic acid (GlcA). The intracellular polysaccharide of Phellinus igniarius Mycelia (PIP) is an irregular spherical accumulation, the surface is rough and not smooth, and the extracellular polysaccharide (PEP) is a crumbly accumulation. PIP has a stronger inhibitory ability for S. aureus and E. coli and a slightly weaker inhibitory effect for B. subtilis; the inhibitory effect of PEP on S. aureus, E. coli, and B. subtilis is slightly inferior to that of PIP.

Exploring Edible Mushrooms for Diabetes: Unveiling Their Role in Prevention and Treatment

Diabetes mellitus is a complex illness in which the body does not create enough insulin to control blood glucose levels. Worldwide, this disease is life-threatening and requires low-cost, side-effect-free medicine. Due to adverse effects, many synthetic hypoglycemic medications for diabetes fail. Mushrooms are known to contain natural bioactive components that may be anti-diabetic; thus, scientists are now targeting them. Mushroom extracts, which improve immune function and fight cancer, are becoming more popular. Mushroom-derived functional foods and dietary supplements can delay the onset of potentially fatal diseases and help treat pre-existing conditions, which leads to the successful prevention and treatment of type 2 diabetes, which is restricted to the breakdown of complex polysaccharides by pancreatic-amylase and the suppression of intestinal-glucosidase. Many mushroom species are particularly helpful in lowering blood glucose levels and alleviating diabetes symptoms. Hypoglycaemic effects have been observed in investigations on Agaricussu brufescens, Agaricus bisporus, Cordyceps sinensis, Inonotus obliqus, Coprinus comatus, Ganoderma lucidum, Phellinus linteus, Pleurotus spp., Poria cocos, and Sparassis crispa. For diabetics, edible mushrooms are high in protein, vitamins, and minerals and low in fat and cholesterol. The study found that bioactive metabolites isolated from mushrooms, such as polysaccharides, proteins, dietary fibers, and many pharmacologically active compounds, as well as solvent extracts of mushrooms with unknown metabolites, have anti-diabetic potential in vivo and in vitro, though few are in clinical trials.

Polysaccharides from Phellinus linteus: A systematic review of their extractions, purifications, structures and functions

Phellinus linteus (P. linteus) is a famous Chinese medicine and has a long history in China. In recent years, P. linteus polysaccharides (PLPs) have attracted extensive attention because of their biological activities such as anti-bacteria, anti-aging, anti-oxidation, anti-inflammation, anti-tumor, hepatoprotective effect and hypoglycemic effect. In this review, we systemically summarized the advances in extractions, purifications and structural characterizations of PLPs, and also analyzed their biological functions and molecular mechanisms. Meanwhile, the structure-activity relationships of PLPs are closely related to their anti-oxidation and anti-tumor activities. So far, the applications of PLPs are still very limited, further exploring structure-activity relationships, biological functions and their mechanisms of PLPs will promote to develop functional foods.

Enhanced Yield of Bioactive Compounds and Antioxidant Activities in Four Fermented Beans of Phellinus linteus Strains (Agaricomycetes) by Solid-State Fermentation

Phellinus linteus is a famous medicinal mushroom which exhibits various biological activities. This study aimed to investigate the effects of solid-state fermentation by Ph. linteus on the yield of bioactive compounds and antioxidant activities of beans. Four bean substrates were prepared and inoculated with inoculum of three strains of Ph. linteus, respectively. During the cultivation, the harvested samples were dried, grounded, extracted, and determined the contents of bioactive compounds and antioxidant activities. The results indicated that the mung bean fermented by Ph. linteus 04 had the highest polysaccharide content (98.8 mg/g). The highest total phenolic and flavonoid contents were in fermented soybeans by Ph. linteus 03 (15.03 mg gallic acid equivalents/g and 63.24 mg rutin equivalents/g, respectively). The 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities of hot water extracts were higher than those of ethanolic extracts for fermented beans by three Ph. linteus strains. However, the superoxide anion radical scavenging ability of ethanolic extracts was higher than those of hot water extracts in the fermented beans of the three strains. The ferrous ion (Fe2+)-chelating abilities of hot water extracts were higher than those of ethanolic extracts in fermented beans by Ph. linteus 03 and 04. In contrast, ethanolic extracts were higher than hot water extracts in fermented beans by Ph. linteus 06. Overall, these results indicate that the fermentation by Ph. linteus strains increased the bioactive compounds and antioxidant activities of four beans.

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.

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.

Conformation and anticancer activity of a novel mannogalactan from the fruiting bodies of Sanghuangporus sanghuang on HepG2 cells

A novel water-soluble mannogalactan (SSPS1) with an average molecular weight of 2.04 × 10⁴ Da was obtained from the fruiting bodies of the Sanghuangporus sanghuang. It revealed that SSPS1 was composed of d-galactose, d-mannose, l-fucose, 3-O-methylgalactose and d-glucose in a ratio of 6.2:3.9:3.1:2.1:1.0. The structural elucidation of SSPS1 consisted of 1, 6-linked α-D-Galp, 1, 6-linked α-D-Manp and 1, 6-linked 3-O-methyl-α-D-Galp backbone with branching at O-2 of 1, 6-α-D-mannosyl residues by α-L-Fucp and α-D-Glcp units. The conformational parameters suggested that a flexible chain conformation of SSPS1 in solution based on light scattering and atomic force microscopy imaging. Intriguingly, it presented potent anticancer activity on HepG2 cell with Rq and Ra values increased dramatically up to 73.93 nm and 53.92 nm compared with the control. The analysis of flow cytometry indicated SSPS1 could induce the apoptosis of HepG2 cells and arrest them via S phase. Western blot assay further uncovered that apoptosis process was triggered by SSPS1 via a mitochondria-mediated signaling pathway, which was evidenced by an increased ratio of Bax/Bcl-2, the release of cytochrome c and the strong activation of caspase-3 and 9. Taken together, these results suggested that SSPS1 might be applied in functional food as an anticancer agent.

The Antioxidant Properties of Mushroom Polysaccharides can Potentially Mitigate Oxidative Stress, Beta-Cell Dysfunction and Insulin Resistance

Diabetes mellitus is a prevalent metabolic and endocrine illness affecting people all over the world and is of serious health and financial concern. Antidiabetic medicine delivered through pharmacotherapy, including synthetic antidiabetic drugs, are known to have several negative effects. Fortunately, several natural polysaccharides have antidiabetic properties, and the use of these polysaccharides as adjuncts to conventional therapy is becoming more common, particularly in underdeveloped nations. Oxidative stress has a critical role in the development of diabetes mellitus (DM). The review of current literature presented here focusses, therefore, on the antioxidant properties of mushroom polysaccharides used in the management of diabetic complications, and discusses whether these antioxidant properties contribute to the deactivation of the oxidative stress-related signalling pathways, and to the amelioration of β-cell dysfunction and insulin resistance. In this study, we conducted a systematic review of the relevant information concerning the antioxidant and antidiabetic effects of mushrooms from electronic databases, such as PubMed, Scopus or Google Scholar, for the period 1994 to 2021. In total, 104 different polysaccharides from mushrooms have been found to have antidiabetic effects. Most of the literature on mushroom polysaccharides has demonstrated the beneficial effects of these polysaccharides on reactive oxygen and nitrogen species (RONS) levels. This review discuss the effects of these polysaccharides on hyperglycemia and other alternative antioxidant therapies for diabetic complications through their applications and limits, in order to gain a better understanding of how they can be used to treat DM. Preclinical and phytochemical investigations have found that most of the active polysaccharides extracted from mushrooms have antioxidant activity, reducing oxidative stress and preventing the development of DM. Further research is necessary to confirm whether mushroom polysaccharides can effectively alleviate hyperglycemia, and the mechanisms by which they do this, and to investigate whether these polysaccharides might be utilized as a complementary therapy for the prevention and management of DM in the future.

Anti-Diabetic Effects of Ethanol Extract from Sanghuangporous vaninii in High-Fat/Sucrose Diet and Streptozotocin-Induced Diabetic Mice by Modulating Gut Microbiota

Type 2 diabetes mellitus (T2DM) may lead to abnormally elevated blood glucose, lipid metabolism disorder, and low-grade inflammation. Besides, the development of T2DM is always accompanied by gut microbiota dysbiosis and metabolic dysfunction. In this study, the T2DM mice model was established by feeding a high-fat/sucrose diet combined with injecting a low dose of streptozotocin. Additionally, the effects of oral administration of ethanol extract from Sanghuangporous vaninii (SVE) on T2DM and its complications (including hypoglycemia, hyperlipidemia, inflammation, and gut microbiota dysbiosis) were investigated. The results showed SVE could improve body weight, glycolipid metabolism, and inflammation-related parameters. Besides, SVE intervention effectively ameliorated the diabetes-induced pancreas and jejunum injury. Furthermore, SVE intervention significantly increased the relative abundances of Akkermansia, Dubosiella, Bacteroides, and Parabacteroides, and decreased the levels of Lactobacillus, Flavonifractor, Odoribacter, and Desulfovibrio compared to the model group (LDA > 3.0, p < 0.05). Metabolic function prediction of the intestinal microbiota by PICRUSt revealed that glycerolipid metabolism, insulin signaling pathway, PI3K-Akt signaling pathway, and fatty acid degradation were enriched in the diabetic mice treated with SVE. Moreover, the integrative analysis indicated that the key intestinal microbial phylotypes in response to SVE intervention were strongly correlated with glucose and lipid metabolism-associated biochemical parameters. These findings demonstrated that SVE has the potential to alleviate T2DM and its complications by modulating the gut microbiota imbalance.

Hypoglycemic and hypolipidemic effects of polysaccharide isolated from Sphacelotheca sorghi in diet-streptozotocin-induced T2D mice

Edible fungus has attracted great interest with many health benefits, and polysaccharides from them have shown great potentials. In this study, polysaccharides were extracted from Sphacelotheca sorghi (Link) Clint. Monosaccharide composition of S. sorghi polysaccharides (SSP) was detected by high-performance anion exchange chromatography (HPAEC) and mainly consists of glucose (70.5%), galactose (15.6%), mannose (7.2%), arabinose (5.8%), and rhamnose (0.9%). Type 2 diabetes (T2D) was induced by a high-fat, high-sugar diet-fed (HFSD) diet with streptozotocin (STZ) injection in mice, and hypoglycemic and hypolipidemic regulations of SSP were evaluated. After oral treatment of high dose of SSP (200 mg/kg/day), the fasting blood glucose (FBG) was reduced by 39.3%, the insulin resistance of T2D mice was relieved, the lipids metabolism disorder caused by diabetes was improved, and the levels of liver glycogen was increased by 34.1%, compared with the model control. Histopathological examination showed that SSP relieved liver damage. Furthermore, SSP regulated glucose and lipid metabolism by activating phosphoinositide 3-kinase/Akt signaling pathway. Overall, SPP is promising to be used as a functional food for the improvement of metabolic disorders. PRACTICAL APPLICATION: For enhancing the utilization rate and economic value of an edible fungi Sphacelotheca sorghi (Link) Clint., the total polysaccharides were isolated and used to investigate the effect of fungi in terms of balancing the levels of blood glucose and lipids. The S. sorghi polysaccharide treatment resolved the symptoms and insulin resistance in mice with diabetes, signifying its potential application in producing different functional foods for preventing or controlling diabetes.

Antioxidant Activity of Mushroom Extracts/Polysaccharides-Their Antiviral Properties and Plausible AntiCOVID-19 Properties

Mushrooms have been long accomplished for their medicinal properties and bioactivity. The ancients benefitted from it, even before they knew that there was more to mushrooms than just the culinary aspect. This review addresses the benefits of mushrooms and specifically dwells on the positive attributes of mushroom polysaccharides. Compared to mushroom research, mushroom polysaccharide-based reports were observed to be significantly less frequent. This review highlights the antioxidant properties and mechanisms as well as consolidates the various antioxidant applications of mushroom polysaccharides. The biological activities of mushroom polysaccharides are also briefly discussed. The antiviral properties of mushrooms and their polysaccharides have been reviewed and presented. The lacunae in implementation of the antiviral benefits into antiCOVID-19 pursuits has been highlighted. The need for expansion and extrapolation of the knowns of mushrooms to extend into the unknown is emphasized.

Screening active fractions from Pinus massoniana pollen for inhibiting ALV-J replication and their structure activity relationship investigation

The objective was to identify the active fractions of polysaccharide against replication of ALV-J and elucidate their structure activity relationship. The optimal extraction conditions were extracting temperature 90℃, pH 9 and the ratio of liquid to solid 30:1. Under these conditions, extraction yield of total polysaccharide was 6.5 % ± 0.19 %. Total polysaccharide was then purified by DEAE-52 cellulose and Sephadex G-200 gel. Three fractions, PPP-1, PPP-2, and PPP-3, were identified with molecular weight of 463.70, 99.41, and 26.97 kDa, respectively. Three polysaccharide fractions were all composed of 10 monosaccharides in different proportions. Compared with PPP-1, which was mainly composed of glucose, PPP-2 and PPP-3 contained a higher proportion of galactose, glucuronic acid and galacturonic acid. The Congo red assay indicated that the PPP-2 may have a triple helical structure, while PPP-1 and PPP-3 were absent. In vitro assay showed that there was no significant cytotoxicity among the polysaccharide fractions under the concentration of 800 μg mL^-1 (P > 0.05). The antiviral test showed that PPP-2 had the strongest activity, indicating PPP-2 was the major antiviral component. The structure-activity relationship showed that the antiviral activities of polysaccharide fractions were affected by their monosaccharide composition, molecular weight, and triple helical structure, which was a result of a combination of multiple molecular structural factors. These results showed that the PPP-2 could be exploited as a valued product for replacing synthetic antiviral drugs, and provided support for future applications of polysaccharide from Pinus massoniana pollen as a useful source for antiviral agent.

Structural characterization and hypoglycemic activity of an intracellular polysaccharide from Sanghuangporus sanghuang mycelia

A neutral polysaccharide (SSIPS1) was isolated and purified from cultured mycelia of Sanghuangporus sanghuang by DEAE Sepharose Fast Flow and Sephacryl S-100 columns. Basic monosaccharide composition indicated that SSIPS1 was mainly composed of d-glucose. The results of methylation and 2D-NMR analysis suggested that the glycosidic linkages of SSIPS1 were elucidated to consisted of 1,4-linked α-d-glucopyranose (Glcp) residues with two branched points at O-6. The two branches were composed of 1,4-linked α-D-Glcp terminated with α-D-Glcp, 1,4-linked α-D-Glcp and 1,4-linked β-Galp terminated by α-D-Glcp. Moreover, its chain conformation was revealed to present a flexible chain conformation in 0.1 NaNO₃ with a hydrodynamic radius and radius of gyration of 3.26 and 6.45 nm by multi-angle laser light scattering, with a single chain of 0.559 nm observed by atomic force microscopy. Further, SSIPS1 exhibited a potential inhibitory activity against α-amylase and α-glucosidase, and it had hypoglycemic effects on in vitro insulin resistance of HepG2 cells as well.

A comparative study on the structures of Grifola frondosa polysaccharides obtained by different decolourization methods and their in vitro antioxidant activities

Decolourization of polysaccharides is one of the crucial procedures that affects their structure, which is closely related to their bioactivity. Here, Grifola frondosa polysaccharide (GFP) was decolourized with H2O2 and AB-8 macroporous resin. Then, two main fractions, named DGFP and SGFP, were obtained by purification with Sepharose CL-4B. The molecular weights of these two polysaccharides were determined to be 6.306 × 106 (±0.410%) Da and 1.174 × 107 (±0.299%) Da by HPSEC. Monosaccharide analysis indicated that DGFP was composed of glucose, mannose, and galactose (32.20 : 1.00 : 1.75), while SGFP consisted entirely of glucose. Despite a backbone →4)-α-Glcp-(1→ in two polysaccharides, reducing ends Rα →3)-α-Glcp and Rβ →4)-β-Glcp were observed in DGFP by 1D/2D NMR. The results suggested that decolourization with low concentrations of H2O2 might alter the structure of GFP and generate new reducing ends. In vitro antioxidant results implied that DGFP exhibited a higher ability to scavenge DPPH and hydroxyl radicals and reduced the over-generated ROS levels in a concentration-dependent manner. These results suggested that the antioxidant effects of GFP could be activated by decolourization with H2O2. Therefore, DGFP might be a more promising natural antioxidant than SGFP.

The Antioxidant Polysaccharide from Semiaquilegia adoxoides (DC.) Makino Adjusts the Immune Response of Mice Infected by Bacteria

Semiaquilegia adoxoides (DC.) Makino is a herbal medicine and it is recorded that its water extract can be used to treat acute diseases caused by bacterial infections. In order to understand the polysaccharide of Semiaquilegia adoxoides (DC.) Makino (SMP), FT-IR and HPLC methods were performed to determine the basic chemical structure and monosaccharide compositions of SMP. The antioxidant capacity of SMP was analyzed by monitoring both the scavenging rate of DPPH and ABTS free radical. To investigate the effects of SMP on the acute bacterial disease, minimum inhibitory concentrations (MICs) of SMP on E. coli or S. aureus were detected; meanwhile, mice were administrated with SMP for 7 days and then infected with E. coli or S. aureus, and the parameters were measured at the 9^th day. Results showed that SMP was a furanose which was mainly composed of glucose (60.3%) and had certain antioxidant activities. Both MIC values of SMP on E. coli and S. aureus were 250 ml/mL, which means that SMP has no direct antibacterial effects. The mice experiments revealed that SMP had potential effects on immunomodulatory by reducing WBC and the expression of serum IL-1, IL-6, and TNF-α and increasing IgM of E. coli or S. aureus infected mice. These findings supported the effect of Semiaquilegia adoxoides (DC.) Makino in folk use with scientific evidence.

Phellinus linteus polysaccharide extract improves insulin resistance by regulating gut microbiota composition

The hypoglycemic effect of Phellinus linteus polysaccharide extract (PLPE) has been documented in several previous studies, but the functional interactions among PLPE, gut microbiota, and the hypoglycemic effect remain unclear. We examined the regulatory effect of PLPE on gut microbiota, and the molecular mechanism underlying improvement of insulin resistance, using a type 2 diabetic rat model. Here, 24 male Sprague-Dawley rats were randomly divided into four groups that were subjected to intervention of saline (normal and model control group), metformin (120 mg/kg.bw), and PLPE (600 mg/kg.bw) by oral administration. After 8 weeks of treatment, PLPE increased levels of short-chain fatty acids (SCFAs) by enhancing abundance of SCFA-producing bacteria. SCFAs maintained intestinal barrier function and reduced lipopolysaccharides content in blood, thereby helping to reduce systemic inflammation and reverse insulin resistance. Our findings suggest that PLPE (in which polysaccharides are the major component) has potential application as a prebiotic for regulating gut microbiota composition in diabetic patients.

The protective effect of Phellinus linteus decoction on podocyte injury in the kidney of FSGS rats

BACKGROUND

This study aimed to investigate the effect of the Phellinus linteus (Mesima) decoction on podocyte injury in a rat model of focal and segmental glomerulosclerosis (FSGS) and evaluate the potential mechanisms.

METHODS

FSGS resembling primary FSGS in humans was established in rats by uninephrectomy and the repeated injection of doxorubicin. The FSGS rats were randomly divided into the model group, low-dose group of P. linteus decoction (PLD-LD), medium-dose group of P. linteus decoction (PLD-MD), and high-dose group of P. linteus decoction (PLD-HD). Blood and urine analysis were performed after 12 weeks and the molecular indicators of renal function and the renal pathological changes were examined.

RESULTS

FSGS developed within 12 weeks in the test group and showed progressive proteinuria and segmental glomerular scarring. Urinary protein, serum creatinine, urea nitrogen, triglycerides and cholesterol were significantly reduced following the 12-week intervention with P.linteus decoction, especially in the PLD-LD group. Renal nephrin and podocin were markedly increased. Moreover, the pathological damage in the renal tissue was alleviated by the PLD-LD intervention.

CONCLUSION

The P. linteus decoction alleviated the podocyte injury in the FSGS rat model, thus minimizing the progression of glomerular sclerosis and improving renal function.

Anti-Diabetic Effects and Mechanisms of Dietary Polysaccharides

Diabetes mellitus is a multifactorial, heterogeneous metabolic disorder, causing various health complications and economic issues, which apparently impacts the human's life. Currently, commercial diabetic drugs are clinically managed for diabetic treatment that has definite side effects. Dietary polysaccharides mainly derive from natural sources, including medicinal plants, grains, fruits, vegetables, edible mushroom, and medicinal foods, and possess anti-diabetic potential. Hence, this review summarizes the effects of dietary polysaccharides on diabetes and underlying molecular mechanisms related to inflammatory factors, oxidative stress, and diabetes in various animal models. The analysis of literature and appropriate data on anti-diabetic polysaccharide from electronic databases was conducted. In vivo and in vitro trials have revealed that treatment of these polysaccharides has hypoglycemic, hypolipidemic, antioxidant, and anti-inflammatory effects, which enhance pancreatic β-cell mass and alleviates β-cell dysfunction. It enhances insulin signaling pathways through insulin receptors and activates the PI3K/Akt pathway, and eventually modulates ERK/JNK/MAPK pathway. In conclusion, dietary polysaccharides can effectively ameliorate hyperglycemia, hyperlipidemia, low-grade inflammation, and oxidative stress in type 2 diabetes mellitus (T2DM), and, thus, consumption of polysaccharides can be a valuable choice for diabetic control.

A Review: The Bioactivities and Pharmacological Applications of Phellinus linteus

Phellinus linteus is a popular medicinal mushroom that is widely used in China, Korea, Japan, and other Asian countries. P. linteus comprises various bioactive components, such as polysaccharides, triterpenoids, phenylpropanoids, and furans, and has proven to be an effective therapeutic agent in traditional Chinese medicine for the treatment and the prevention of various diseases. A number of studies have reported that P. linteus possesses many biological activities useful for pharmacological applications, including anticancer, anti-inflammatory, immunomodulatory, antioxidative, and antifungal activities, as well as antidiabetic, hepatoprotective, and neuroprotective effects. This review article briefly presents the recent progress made in understanding the bioactive components, biological activities, pharmacological applications, safety, and prospects of P. linteus, and provides helpful references and promising directions for further studies of P. linteus.

Effects of Ultrasound Treatment on Extraction and Rheological Properties of Polysaccharides from Auricularia Cornea var. Li

Auricularia cornea var. Li. is an edible fungi and polysaccharides in Auricularia cornea var. Li. may have bioactive activities. Polysaccharides from Auricularia cornea var. Li. (ACP) was extracted using ultrasound-assisted extraction (UAE) method and compared with hot water extraction (HWE) for extraction yield, extraction rate, purity of polysaccharides, microstructure of residues after extraction, preliminary structure and rheological properties of polysaccharides. Optimum conditions for UAE (particle size of 150⁻200 mesh, water to raw material ratio of 70:1, extraction temperature at 70 °C for 40 min, ultrasonic amplitude of 40%) and HWE (particle size of 150⁻200 mesh, water to raw material ratio of 60:1, extraction temperature at 90 °C for 3.0 h) were obtained via single-factor experiment. Under optimum conditions, extraction yield of polysaccharides by UAE was 30.99 ± 1.93% which showed no significant difference with that by HWE (30.35 ± 1.67%) (P > 0.05). Extraction rate (29.29 ± 1.41%) and purity (88.62 ± 2.80%) of polysaccharides by UAE were higher than those by HWE (extraction rate of 24.95 ± 2.78% and purity of 75.33 ± 6.15%) (P < 0.05). Scanning Electron Microscopy (SEM) images of residues by UAE showed more broken cells than those by HWE. Fourier Transform Infrared (FTIR) spectra showed that the dialyzed ACP extracted by HWE and UAE (DACP-HWE and DACP-UAE) had similar characteristic absorption peaks of polysaccharides. Both DACP-HWE and DACP-UAE solutions showed typical shear thinning and temperature-independent behaviors (25⁻90 °C) and UAE resulted in polysaccharides with remarkably lower viscosity in comparison with HWE. DACP-UAE solutions exhibited more liquid-like state while DACP-HWE solutions solid-like system. Data indicated that ultrasound treatment may be a useful means for extraction of polysaccharides from Auricularia cornea var. Li.

Antioxidant and Antiproliferative Activities of Modified Polysaccharides Originally Isolated from Morchella Angusticepes Peck

Polysaccharides extracted from Morchella angusticepes Peck (PMEP) were chemically modified to obtain sulfated, carboxymethylated, and acetyled derivatives. Results showed that the acetyled derivatives with the degree of substitution (0.40 ± 0.07) exerted higher antioxidant ability than native polysaccharides, demonstrating inhibitory effects on growth of human hepatoma cells (EC₅₀  = 0.710 ± 0.002 mg/mL) and human colon cancer cells (EC₅₀  =  1.229 ± 0.008 mg/mL). It indicated that the acetylation was a favorable way to enhance the bioactivities of PMEP. PRACTICAL APPLICATION: Polysaccharides extracted from Morchella angusticepes Peck (PMEP) have many health-promoting properties. Chemical modifications could improve the bioactivities of polysaccharides. We demonstrated that acetylation enhanced the cellular antioxidant and antiproliferative activities of PMEP. The results support further research that explores clinical utility, and may justify ex vivo and in vivo designs toward that end.

Hypoglycemic and Hypolipidemic Effects of Phellinus Linteus Mycelial Extract from Solid-State Culture in A Rat Model of Type 2 Diabetes

Hypoglycemic and hypolipidemic effects of P. linteus have been observed in numerous studies, but the underlying molecular mechanisms are unclear. In this study, we prepared P. linteus extract (PLE) from mycelia of solid-state culture, and evaluated its hypoglycemic and hypolipidemic effects in rat models of high-fat diet (HFD)-induced and low-dose streptozotocin (STZ)-induced type 2 diabetes. PLE treatment effectively reduced blood glucose levels, and improved insulin resistance and lipid and lipoprotein profiles. The hypoglycemic effect of PLE was based on inhibition of key hepatic gluconeogenesis enzymes (FBPase, G6Pase) expression and hepatic glycogen degradation, and consequent reduction of hepatic glucose production. PLE also: (i) enhanced expression of CPT1A and ACOX1 (key proteins involved in fatty acid β-oxidation) and low-density lipoprotein receptor (LDLR) in liver, thus promoting clearance of triglycerides and LDL-C; (ii) inhibited expression of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) in liver, thus reducing cholesterol production; (iii) displayed strong hepatoprotective and renal protective effects. Our findings indicate that PLE has strong potential functional food application in adjuvant treatment of type 2 diabetes with dyslipidemia.

Mushroom Polysaccharides: Chemistry and Antiobesity, Antidiabetes, Anticancer, and Antibiotic Properties in Cells, Rodents, and Humans

More than 2000 species of edible and/or medicinal mushrooms have been identified to date, many of which are widely consumed, stimulating much research on their health-promoting properties. These properties are associated with bioactive compounds produced by the mushrooms, including polysaccharides. Although β-glucans (homopolysaccharides) are believed to be the major bioactive polysaccharides of mushrooms, other types of mushroom polysaccharides (heteropolysaccharides) also possess biological properties. Here we survey the chemistry of such health-promoting polysaccharides and their reported antiobesity and antidiabetic properties as well as selected anticarcinogenic, antimicrobial, and antiviral effects that demonstrate their multiple health-promoting potential. The associated antioxidative, anti-inflammatory, and immunomodulating activities in fat cells, rodents, and humans are also discussed. The mechanisms of action involve the gut microbiota, meaning the polysaccharides act as prebiotics in the digestive system. Also covered here are the nutritional, functional food, clinical, and epidemiological studies designed to assess the health-promoting properties of polysaccharides, individually and as blended mixtures, against obesity, diabetes, cancer, and infectious diseases, and suggestions for further research. The collated information and suggested research needs might guide further studies needed for a better understanding of the health-promoting properties of mushroom polysaccharides and enhance their use to help prevent and treat human chronic diseases.

Structural characterization and anti-aging activity of a novel extracellular polysaccharide from fungus Phellinus sp. in a mammalian system

Little is known about the chemical structure of purified extracellular polysaccharides from Phellinus sp., a fungal species with known medicinal properties. A combination of IR spectroscopy, methylation analysis and NMR were performed for the structural analysis of a purified extracellular polysaccharide derived from Phellinus sp. culture, denoted as SHP-1, along with an evaluation of the anti-aging effect in vivo of the polysaccharide supplementation. The structure of SHP-1 was established, with a backbone composed of →2,4)-α-d-glucopyranose-(1→ and →2)-β-d-mannopyranose-(1→ and two terminal glucopyranose branches. Biochemical analysis from mammalian animal experiments demonstrated that SHP-1 possesses the ability to enhance antioxidant enzyme activities, such as catalase (CAT) and superoxide dismutase (SOD) activities, Trolox equivalent antioxidant capacity (TEAC) in serum of d-galactose-aged mice, while reducing lipofuscin levels, another indicator of cell aging, indicating a potential association with anti-aging activities in a dose dependent manner. This compound had a favourable influence on immune organ indices, and a marked amelioration ability of histopathological hepatic lesions such as necrosis, karyolysis and reduced inflammation and apoptosis in mouse hepatocytes. These results suggest that SHP-1 has strong antioxidant activities and a significant protective effect against oxidative stress or hepatotoxicity induced by d-galactose in mice and it could be developed as a food ingredient or a pharmaceutical to prevent many age-associated diseases such as major depressive disorder and hepatotoxicity. To our knowledge, this is the first report on the antioxidant effects of a novel purified exopolysaccharide derived from Phellinus sp.

Anti-diabetic polysaccharides from natural sources: A review

Diabetes mellitus (DM) is a metabolic disease attracted worldwide concerns, which severely impairs peoples' quality of life and is attributed to several life-threatening complications, including atherosclerosis, nephropathy and retinopathy. The current therapies for DM include mainly oral anti-diabetic drugs and insulin. However, continuous use of these causes insulin resistance and side-effects, and the demand of effective, nontoxic and affordable drugs for DM patients is eager. Several previous studies have shown that non-toxic biological macromolecules, mainly polysaccharides, possess prominent efficacies on DM. Based on these encouraging observations, a great deal of efforts have been focused on discovering anti-diabetic polysaccharides for the development of effective therapeutics for DM. This review focuses on the advancements in the anti-diabetic efficacy of various natural polysaccharides and polysaccharide complexes from 2010 to 2015.

A proteomic analysis of mushroom polysaccharide-treated HepG2 cells

The anti-tumor properties of fungal polysaccharides have gained significant recognition in Asia and tropical America. In this study, the differential expression of proteins in normal HepG2 cells and those treated with polysaccharides that had been isolated from Phellinus linteus (PL), Ganoderma lucidum (GL) and Auricularia auricula (AA) was investigated. Using two-dimensional electrophoresis (2DE), a total of 104 protein spots were determined to be overexpressed in these cells compared with noncancerous regions. A total of 59 differentially expressed proteins were identified through MALDI-TOF-MS. In addition, 400 biological processes (BP), 133 cell components (CC) and 146 molecular functions (MF) were enriched by Gene Ontology (GO) analysis, and 78 KEGG pathways were enriched by pathway enrichment. Protein-Protein Interaction (PPI) analysis demonstrated the interaction networks affected by polysaccharides in HepG2 cells. Then, DJ-1 and 14-3-3 were identified as the key proteins in the networks, and the expression of the mRNA and proteins were evaluated using Real-time quantitative PCR (qRT-PCR) and Western blotting (WB), respectively. The results were in agreement with the 2DE. These results provided information on significant proteins of hepatocellular carcinoma (HCC) and form an important basis for the future development of valuable medicinal mushroom resources.

A novel polysaccharide from mycelia of cultured Phellinus linteus displays antitumor activity through apoptosis

Two novel polysaccharides termed PLPS-1 and PLPS-2 were isolated from mycelia of cultured Phellinus linteus by hot water extraction, purified by DEAE-52 cellulose and Sephadex G-100 column chromatography, and structurally characterized by FTIR and NMR spectroscopy, GC-MS, periodate oxidation/Smith degradation, and methylation analysis. The monosaccharide compositions of PLPS-1 (MW 2.5×10(5)Da) and PLPS-2 (MW 2.8×10(4)Da) were respectively Glc, Ara, Fuc, Gal, and Xyl in molar ratio 21.964:1.336:1.182:1:1, and Glc, Gal, Man, Ara, Fuc, Xyl in molar ratio 14.368:2.594:1.956:1.552:1.466:1; i.e., both were heteropolysaccharides. The backbone of PLPS-1 consisted primarily of repeating α-d-Glc(1→4)-α-d-Glc(1→6) units, while that of PLPS-2 consisted of α-(1→3)-d-Glc and α-(1→6)-d-Glc. The side branches were also different in their carbohydrate components. In in vitro antitumor assays, PLPS-1 displayed strong anti-proliferative effect against S-180 sarcoma cells through apoptosis, whereas PLPS-2 had no such effect. The difference in antitumor activity between the two PLPS evidently results from their structural differences. PLPS-1 has potential as a novel anticancer agent.