Antioxidant and hepatoprotective activities of residue polysaccharides by Pleurotus citrinipileatus

An Overview on Mushroom Polysaccharides: Health-promoting Properties, Prebiotic and Gut Microbiota Modulation Effects and Structure-function Correlation

Mushroom polysaccharides are recognized as "biological response modifiers". Besides several bioactivities, a growing interest in their prebiotic potential has been raised due to the gut microbiota modulation potential. This review comprehensively summarizes mushroom polysaccharides' biological properties, structure-function relationship, and underlying mechanisms. It provides a recent overview of the key findings in the field (2018-2024). Key findings and limitations on structure-function correlation are discussed. Although most studies focus on β-glucans or extracts, α-glucans and chitin have gained interest. Prebiotic capacity has been associated with α-glucans and chitin, while antimicrobial and wound healing potential is attributed to chitin. However, further research is of utmost importance. Human fecal fermentation is the most reported approach to assess prebiotic potential, indicating impacts on intestinal biological, mechanical, chemical and immunological barriers. Gut microbiota dysbiosis has been directly connected with intestinal, cardiovascular, metabolic, and neurological diseases. Concerning gut microbiota modulation, animal experiments have suggested proinflammatory cytokines reduction and redox balance re-establishment. Most literature focused on the anticancer and immunomodulatory potential. However, anti-inflammatory, antimicrobial, antiviral, antidiabetic, hypocholesterolemic, antilipidemic, antioxidant, and neuroprotective properties are discussed. A significant overview of the gaps and research directions in synergistic effects, underlying mechanisms, structure-function correlation, clinical trials and scientific data is also given.

Extraction, Purification, and Structural Characterization of Polysaccharides from Sanghuangporus vaninii with Anti-Inflammatory Activity

In order to obtain homogeneous Sanghuangporus vaninii polysaccharides with antioxidant and anti-inflammatory activities, a response surface method (RSM) was used to compare the polysaccharide extraction rate of hot water extraction and ultrasonic-assisted extraction from Sanghuangporus vaninii. The optimal conditions for ultrasonic-assisted extraction were determined as follows: an extraction temperature of 60 °C, an extraction time of 60 min, a solid-liquid ratio of 40 g/mL, and an ultrasonic power of 70 W. An SVP (Sanghuangporus vaninii polysaccharides) extraction rate of 1.41% was achieved. Five homogeneous monosaccharides were obtained by gradient ethanol precipitation with diethylaminoethyl-cellulose (DEAE) and SephadexG-100 separation and purification. The five polysaccharides were characterized by high performance liquid chromatography, the ultraviolet spectrum, the Fourier transform infrared spectrum, TG (thermogravimetric analysis), the Zeta potential, and SEM (scanning electron microscopy). The five polysaccharides had certain levels of antioxidant activity in vitro. In addition, we the investigated the anti-inflammatory effects of polysaccharides derived from Sanghuangporus vaninii on lipopolysaccharide (LPS)-induced RAW 264.7 cells and Kupffer cells. Further, we found that SVP-60 significantly inhibited the levels of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-induced RAW 264.7 cells and promoted the level of the anti-inflammatory cytokine IL-10 in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Our study provides theoretical support for the potential application of Sanghuangporus vaninii in the field of antioxidant and anti-inflammatory activities in vitro.

Statistical optimization and characterization of fucose-rich polysaccharides extracted from pumpkin (Cucurbita maxima) along with antioxidant and antiviral activities

Biologically active phytochemicals from pumpkin reveal versatile medical applications, though little is known about their antiviral activity. The fucose-rich polysaccharide extraction conditions were optimized through Box-Behnken design and purified by column chromatography. The purified fucose-rich polysaccharide was characterized through SEM, FT-IR, ¹H NMR, XRD, TGA, and GS-MS. The analysis results revealed an irregular and porous surface of the purified polysaccharide with high fucose, rhamnose, galactose, and glucose contents. The tested fucose-rich polysaccharides revealed significant antioxidant and anti-inflammatory activity at very low concentrations. The purified fucose-rich polysaccharides exerted a broad-spectrum antiviral activity against both DNA and RNA viruses, accompanied by high safety toward normal cells, where the maximum safe doses (EC₁₀₀) were estimated to be about 3-3.9 mg/mL for both Vero and PBMC cell lines. Treatment of HCV, ADV7, HSV1, and HIV viruses with the purified polysaccharides showed a potent dose-dependent inhibitory activity with IC₅₀ values of 95.475, 20.96, 5.213, and 461.75 μg/mL, respectively. This activity was hypothesized to be through inhibiting the viral entry in HCV infection and inhibiting the reverse transcriptase activity in HIV. The current study firstly reported the antioxidant, anti-inflammatory, and antiviral activities of Cucurbita maxima fucose-rich polysaccharide against several viral infections.

Influences of Some Aromatic Plants on Volatile Compounds and Bioactivity of Cultivated Pleurotus citrinopileatus and Pleurotus djamor

Two edible Pleurotus species, namely, Pleurotus citrinopileatus and Pleurotus djamor grown in the media of mulberry shavings which were substituted with myrtle, bay laurel, and rosemary leaves were studied. According to volatile profiles, 13 aldehydes, 8 ketones, 7 alcohols, 5 aromatic compounds and 4 terpenes were totally identified. Rosemary leaves were very effective for decreasing the concentrations of some oxidation products in Pleurotus citrinopileatus, but the same impact was not seen in Pleurotus djamor. The high amount of benzaldehyde (41.80 %) detected in bay laurel medium might have played a role in preventing bioactivity. Control Pleurotus citrinopileatus and Pleurotus djamor had a total phenolic content of 4284.89 and 3080.04 mg GAE per kg DM, respectively, and the enrichment of composts with aromatic plant leaves caused significant differences in Pleurotus djamor (p<0.05). Myrtle addition increased total phenolic content and antioxidant activities (by DPPH and FRAP assays) of Pleurotus djamor mushroom as 342.29 mg GAE/kg DM, 0.43 μmol TE/g DM and 2.07 μmol TE/g DM, respectively, when compared to intact one.

Natural polysaccharides as potential anti-fibrotic agents: A review of their progress

Fibrosis, as a common disease which could be found in nearly all organs, is normally initiated by organic injury and eventually ended in cellular dysfunction and organ failure. Currently, effective and safe therapeutic strategies targeting fibrogenesis still in highly demand. Natural polysaccharides derived from natural resources possess promising anti-fibrosis potential, with no deleterious side effects. Based on the etiology and pathogenesis of fibrosis, this review summarizes the intervention effects and mechanisms of natural polysaccharides in the prevention and treatment of fibrosis. Natural polysaccharides are able to regulate each phase of the fibrogenic response, including primary injury to organs, activation of effector cells, the elaboration of extracellular matrix (ECM) and dynamic deposition. In addition, polysaccharides significantly reduce fibrosis levels in multiple organs including heart, lung, liver and kidney. The investigation of the pathogenesis of fibrosis indicates that mechanisms including the inhibition of TGF-β/Smad, NF-κB, HMGB1/TLR4, cAMP/PKA signaling pathways, MMPs/TIMPs system as well as microRNAs are promising therapeutic targets. Natural polysaccharides can target these mediators or pathways to alleviate fibrosis. The information reviewed here offer new insights into the understanding the protective role of natural polysaccharides against fibrosis, help design further experimental studies related to polysaccharides and fibrotic responses, and shed light on a potential treatment for fibrosis.

The Regulatory Roles of Polysaccharides and Ferroptosis-Related Phytochemicals in Liver Diseases

Liver disease is a global health burden with high morbidity and mortality worldwide. Liver injuries can develop into severe end-stage diseases, such as cirrhosis or hepatocellular carcinoma, without valid treatment. Therefore, identifying novel drugs may promote liver disease treatment. Phytochemicals, including polysaccharides, flavonoids, alkaloids, and terpenes, are abundant in foods and medicinal plants and have various bioactivities, such as antioxidation, immunoregulation, and tumor killing. Recent studies have shown that many natural polysaccharides play protective roles in liver disease models in vitro and in vivo, such as fatty liver disease, alcoholic liver disease, drug-induced liver injury, and liver cancer. The mechanisms of liver disease are complex. Notably, ferroptosis, a new type of cell death driven by iron and lipid peroxidation, is considered to be the key mechanism in many hepatic pathologies. Therefore, polysaccharides and other types of phytochemicals with activities in ferroptosis regulation provide novel therapeutic strategies for ferroptosis-related liver diseases. This review summarizes our current understanding of the mechanisms of ferroptosis and liver injury and compelling preclinical evidence of natural bioactive polysaccharides and phytochemicals in treating liver disease.

Current trends in the anti-photoaging activities and mechanisms of dietary non-starch polysaccharides from natural resources

Photoaging is a complex and multistage process triggered mainly by ultraviolet (UV) radiation due to exposure to sunlight. Photoaging induces DNA damage and oxidative stress that initiate an inflammatory response and an increase of matrix metalloproteinases (MMPs) expression, which results in cumulative changes in skin appearance, structure, and functions, and eventually causes skin carcinogenesis. Dietary polysaccharides from bio-resources have been utilized as functional ingredients in healthy food, cosmetics, and drug due to their good bioactivities. However, a systematic introduction to their effects and underlying mechanisms in anti-photoaging is limited. This review discusses the damage and pathogenesis of UV-induced photoaging and summarizes the up-to-date advances in research on the anti-photoaging activity of non-starch polysaccharides from natural edible resources considering the influence of oxidative stress, DNA damage, MMPs regulation, inflammation, and melanogenesis, primarily focusing on the cellular and molecular mechanisms. This paper will help to understand the anti-photoaging functions of dietary non-starch polysaccharides from natural resources and further application in drug and functional food.

Biological activities of Pleurotus spp. polysaccharides: A review

Mushrooms are consumed for their nutrients and therapeutic bioactive compounds and are used medicinally in Chinese and Japanese medicine traditions since time immemorial. Members of the genus Pleurotus form a heterogeneous group of edible species with outstanding nutritional profiles rich in fiber, vitamins (thiamine, riboflavin, ascorbic acid, ergosterine, and niacin), micro and macro-elements (phosphorus and iron), and carbohydrates. Pleurotus is one of the most diversified medicinal and edible mushrooms related to the composition of chemical structures such as polysaccharides, glycoproteins, and secondary metabolites such as alkaloids and betalains. The cultivation of Pleurotus spp. on lignocellulosic wastes represents one of the most economically and cost-effective organic recycling processes, especially for the utilization of different feasible and cheap recyclable residues. Also, several Pleurotus spp. have the ability to remove phenolic compounds from wastewater with the action of phenoloxidase activity. Here, we have reviewed the chemistry of such polysaccharides and their reported biological activities, namely, anti-inflammatory, immunomodulatory, anti-diabetic, anti-tumor, antioxidant, etc. The mechanism of action and effects of novel polysaccharides extracted from various species of Pleurotus have been studied. The current study will be beneficial for guiding future research projects on the above concept and investigating more deeply the health of human beings. PRACTICAL APPLICATIONS: Mushrooms are one of the most delicious foods around the globe and have many medicinal properties for decades. Various Pleurotus species have been in focus in recent years because of their palatability and medicinal importance too. It contains many bioactive compounds among which polysaccharides are valued to a great extent. Many biological activities are exerted by polysaccharides derived from the Pleurotus spp., namely, anti-tumor, antioxidant, and many more. They are responsible for significant physiological responses in animals, animal-alternative in vitro models, and humans. Their important physicochemical characteristics benefit their use in the food industry as well. So, the biological activities of these Pleurotus spp. polysaccharides will provide an insight to develop Pleurotus spp. as functional foods, because of their nutritional value and presence of bioactive components.

Zingiber roseum Rosc. rhizome: A rich source of hepatoprotective polyphenols

Zingiber roseum is native to Bangladesh and widely used in folk medicine. This present study was designed to assess the ameliorative potential of Zingiber roseum rhizome extract in carbon tetrachloride (CCl₄) induced hepatotoxicity in mice model. Seven phenolic compounds were identified and quantified by HPLC analysis in the plant extract, including quercetin, myricetin, catechin hydrate, trans-ferulic acid, trans-cinnamic acid, (-) epicatechin, and rosmarinic acid. Hepatotoxicity was induced by administrating a single intraperitoneal injection of CCl₄ (10 mL/kg) on 7th day of treatment. The results revealed that plant extract at all doses (100, 200 and 400 mg/kg) significantly reduced (p < 0.05) the elevated serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) concentrations, and these effects were comparable to that of standard drug silymarin. Histopathological examination also revealed the evidence of recovery from CCL₄ induced cellular damage when pretreated with Z. roseum rhizome extract. The in-vivo hepatoprotective effects were further investigated by the in-silico study of the aforementioned compounds with liver-protective enzymes such as superoxide dismutase (SOD), peroxiredoxin, and catalase. The strong binding affinities (ranging from -7.3359 to -9.111 KCal/mol) between the phenolic compounds (except trans-cinnamic acid) and oxidative stress enzymes inhibit ROS production during metabolism. The compounds were also found non-toxic in computational prediction, and a series of biological activities like antioxidant, anticarcinogen, cardio-protectant, hepato-protectant have been detected.

Periplaneta americana Oligosaccharides Exert Anti-Inflammatory Activity through Immunoregulation and Modulation of Gut Microbiota in Acute Colitis Mice Model

The incidence and prevalence of inflammatory bowel disorders (IBD) are increasing around the world due to bacterial infection, abnormal immune response, etc. The conventional medicines for IBD treatment possess serious side effects. Periplaneta americana (P. americana), a traditional Chinese medicine, has been used to treat arthritis, fever, aches, inflammation, and other diseases. This study aimed to evaluate the anti-inflammatory effects of oligosaccharides from P. Americana (OPA) and its possible mechanisms in vivo. OPA were purified and biochemical characterization was analyzed by HPGPC, HPLC, FT-IR, and GC–MS. Acute colitis mice model was established, the acute toxicity and anti-inflammatory activity were tested in vivo. The results showed OPA with molecular mass of 1.0 kDa were composed of 83% glucose, 6% galactose, 11% xylose, and the backbone was (1→4)-Glcp. OPA had potent antioxidant activities in vitro and significantly alleviated the clinical symptoms of colitis, relieved colon damage without toxic side effects in vivo. OPA exhibited anti-inflammatory activity by regulating Th1/Th2, reducing oxidative stress, preserving intestinal barrier integrity, and inhibiting TLR4/MAPK/NF-κB pathway. Moreover, OPA protected gut by increasing microbial diversity and beneficial bacteria, and reducing pathogenic bacteria in feces. OPA might be the candidate of complementary and alternative medicines of IBD with low-cost and high safety.

A water-soluble selenium-enriched polysaccharide produced by Pleurotus ostreatus: Purification, characterization, antioxidant and antitumor activities in vitro

The development and application of new selenium-enriched polysaccharides has become a critical topic in recent years. In this study, a natural selenium-enriched polysaccharide fraction (Se-POP-21) produced by Pleurotus ostreatus was purified, characterized, and investigated the antioxidant and antitumor activities in vitro. The Se-POP-21 was mainly composed of mannose, glucose, galactose and arabinose, with a molar ratio of 18.01:2.40:26.15:7.34, of which molecular weight was 15,888 Da and the selenium content was 5.31 μg/g. Spectral analysis demonstrated that Se-POP-21 represented a non-triple helix pyranopolysaccharide and selenium occurred in the form of C-O-Se and SeO. Molecular size and morphology studies showed that Se-POP-21 exhibited a spherical shape with a particle size distribution between 100 and 200 nm, even though Se-POP-21 aggregates were also found with a size between 500 and 600 nm. In addition, Se-POP-21 showed strong scavenging capacity to DPPH and hydroxyl radical. More, cell experiments showed that Se-POP-21 could reduce viability of A549, SKOV3, HepG2 and MCF-7 cells, induce apoptosis and inhibit metastasis of A549 cells. A potential mechanism was that Se-POP-21 inhibited the epithelial-to-mesenchymal transition of cancer cells. Se-POP-21 featured no significant effect on normal cells. Se-POP-21 showed great potential to develop into a natural antioxidant or low-toxic antitumor drug.

The structural characteristics, antioxidant and hepatoprotection activities of polysaccharides from Chimonanthus nitens Oliv. leaves

This work aimed to investigate the structural characteristics, antioxidant activities and hepatoprotection effect of Chimonanthus nitens Oliv. leaves polysaccharides (COP) on alcohol-induced oxidative damage in mice. Physical and chemical analysis showed that COP contained four monosaccharides including arabinose (Ara), mannose (Man), glucose (Glu) and galactose (Gal), with mass percentages of 26.6%, 5.1%, 32.2% and 36.0%, respectively, which was a heteropolysaccharide with both α- and β- configurations. In vivo experiments indicated that oral administration COP significantly reduced the levels of ALT, AST and MDA in serum, and significantly increased the activity of SOD and GSH-Px. Mice pretreated with COP had a higher superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity in liver and lower content of TNF-α, IL-6 and IL-1β in the liver and serum when compared with alcohol exposure. In addition, the liver histopathological changes induced by alcohol returned to normal in the COP pretreatment group. These results suggest that COP has a protective effect on acute liver injury induced by alcohol.

Hepatoprotection of pine nut polysaccharide via NRF2/ARE/MKP1/JNK signaling pathways against carbon tetrachloride-induced liver injury in mice

Previously, we obtained a purified polysaccharide (PNP40c-1) from Pinus koraiensis pine nut and reported its protective effect on carbon tetrachloride (CCl₄)-induced liver injury in vitro. The object of this study is to investigate its hepatoprotective activity in vivo and elucidate the mechanism underlying the hepatoprotection. PNP40c-1 effectively prevented the accumulation of serum liver injury biomarkers including alanine aminotransferase, aspartate aminotransferase, alkaline phpsphatase and total bilirubin stimulated by CCl₄. The pathological changes in PNP40c-1-treated mice livers were also markedly ameliorated. Results showed that PNP40c-1 suppressed the production of reactive oxygen species (ROS) and lipid peroxidation, upregulated Nrf2/ARE pathway and enhanced the antioxidant capacity of hepatocytes. Furthermore, the reaction between Nrf2 and ARE promoted the generation of Mkp1, which inhibited the activation of JNK induced by CCl₄, and suppressed hepatocytes apoptosis by regulating the protein expression of Bax, cleaved-Caspase-3 and Bcl2, exerting hepatoprotective activity. Taken together, upregulation of Nrf2/ARE pathway and suppression of JNK activation via Nrf2/ARE/Mkp1/JNK signaling pathways are the main mechanisms underlying the hepatoprotective effect of PNP40c-1 against CCl₄-induced mice liver injury. These results indicated that PNP40c-1 has potential to serve as a hepatoprotective agent against chemical induced hepatotoxicity.

Extraction Optimization of Galla Turcica Polysaccharides and Determination of Its Antioxidant Activities In Vitro

Though natural polysaccharides commonly show antioxidant activities, the current research on the isolation of polysaccharides from Galla Turcica and their antioxidant activities still remain as an ongoing challenge. In this work, response surface analysis was employed to optimize an ultrasonic-assisted extraction method for polysaccharides of Galla Turcica. Their antioxidant and free radical scavenging activities were then evaluated using 2,2-diphenyl-1-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), total antioxidant activity, and iron ion reduction assays. Moreover, the protective effects of polysaccharides of Galla Turcica were determined on human embryonic kidney fibroblast 293 and hepatoma 7721 cells by cell proliferation assay. Overall, the key parameters of Galla Turcica polysaccharides extraction were optimized as crushing degree 100 mesh, ultrasonic time 50 min, and materials–liquid ratio 1:50. The isolated polysaccharides presented dose-dependent antioxidant and free radical scavenging effects in vitro. It also demonstrated an effective protective effect for human cells under oxidative damage. The results firstly determined the antioxidant activities of polysaccharides from Galla Turcica, thus providing a new natural resource for future investigation and development of the polysaccharides-based antioxidant drugs, health products, or additives.

Comparative study on hepatoprotection of pine nut (Pinus koraiensis Sieb. et Zucc.) polysaccharide against different types of chemical-induced liver injury models in vivo

A novel polysaccharide (PNP80b-2) was obtained from Pinus koraiensis pine nut, which has been proved to possess good hepatoprotective effects in vitro. This study comprehensively investigated its hepatoprotective activities against different types of chemical-induced liver injury in vivo. Carbon tetrachloride, alcohol and acetaminophen were used as hepatic toxicants to establish chemical pollutant-induced liver injury (CILI) model, alcohol induced-liver injury (AILI) model and drug-induced liver injury (DILI) model, respectively. The results showed that PNP80b-2 prevented elevation of biomarkers for liver injury in each model, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and total bilirubin (TBIL). The expression of cytochrome P450 in damaged hepatocytes was also downregulated. Additionally, PNP80b-2 enhanced hepatic antioxidant capacity through upregulating the expression of NRF2 and HO-1, thereby increasing superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities and decreasing malondialdehyde (MDA) levels. The uncontrolled production of inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) in CILI, AILI and DILI models was also suppressed by PNP80b-2. By contrast, PNP80b-2 exerted the strongest hepatoprotection against AILI model, through improving hepatic antioxidant capacity via NRF2/ARE pathway and regulating inflammation response. Thus, PNP80b-2 is a promising functional food to prevent AILI.

Polysaccharides of mushroom Pleurotus spp.: New extraction techniques, biological activities and development of new technologies

The biodiversity of mushrooms Pleurotus spp. is impressive due to its complexity and diversity related to the composition of chemical structures such as polysaccharides, glycoproteins and secondary metabolites such as alkaloids, flavonoids and betalains. Recent studies of polysaccharides and their structural elucidation have helped to direct research and development of technologies related to pharmacological action, production of bioactive foods and application of new, more sophisticated extraction tools. The diversity of bioactivities related to these biopolymers, their mechanisms and routes of action are constant focus of researches. The elucidation of bioactivities has helped to formulate new vaccines and targeted drugs. In this context, in terms of polysaccharides and the diversity of mushrooms Pleurotus spp., this review seeks to revisit the genus, making an updated approach on the recent discoveries of polysaccharides, new extraction techniques and bioactivities, emphasising on their mechanisms and routes in order to update the reader on the recent technologies related to these polymers.