Structure characterization of an agavin-type fructan isolated from Polygonatum cyrtonema and its effect on the modulation of the gut microbiota in vitro.

The herbal medicine Polygonatum cyrtonema is highly regarded in China for its medicinal and dietary properties. However, further research is needed to elucidate the structure of its polysaccharide and understand how it promotes human health by modulating the gut microbiota. This study aims to investigate a homogeneous polysaccharide (PCP95-1-1) from Polygonatum cyrtonema and assess its susceptibility to digestion as well as its utilization by intestinal microbiota. The results confirmed that PCP95-1-1 is an agavin-type fructan, which possesses two fructose chains, namely ß-(2 â†’ 6) and ß-(2 â†’ 1) fructosyl-fructose, attached to the sucrose core, and has branches of ß-D-Fruf residues. Moreover, PCP95-1-1 demonstrated resistance to digestion and maintained its reducing sugar content throughout the digestive system, indicating it could reach the gut without being digested. In vitro fermentation of PCP95-1-1 significantly decreased the pH value (p < 0.05) while notably increasing the production of short-chain fatty acids (SCFAs), confirming its utilization by human gut microbiota. Additionally, PCP95-1-1 exhibited a significant ability (p < 0.05) to beneficial bacteria such as Megamonas and Bifidobacterium, while reducing the presence of facultative or conditional pathogens such as Escherichia-Shigella and Klebsiella at the genus level. Consequently, PCP95-1-1 has the potential to positively influence physical well-being by modulating the gut microbiota environment and can be developed as a functional food.

Antimicrobial, antioxidant, anti-inflammatory, and cytotoxic activities of Cordyceps militaris spent substrate.

Cordyceps militaris is a medicinal mushroom and has been extensively used as a traditional medicine in East Asia. After the chrysalis seeds are matured and harvested, the spent substrate of C. militaris still contains active ingredients but is usually discarded as waste. This study aimed to determine the antioxidant and anti-inflammatory activities of C. militaris spent substrate extract and its inhibitory activity on the Malassezia commensal yeasts that can cause dandruff and seborrheic dermatitis. Active substances in the spent substrate of C. militaris were extracted using a hot water extraction method and were used for the determination of antioxidant activity by measuring their ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radicals, hydrogen peroxide, and superoxide anions. The ability to inhibit Malassezia was analyzed using the broth microdilution method, and the reparative effect on oxidative damage in HaCaT cells was measured using in vitro cell analysis. Respiratory burst evaluation was used to determine the anti-inflammatory capacity of extracts. Analysis of the Malassezia-inhibiting activity of the extracts showed that the minimum inhibitory concentration was 6.25 mg/mL. The half maximal inhibitory concentration (IC50) values of DPPH, O2-, H2O2 and OH- were 3.845 mg/mL, 2.673 mg/mL, 0.037 mg/mL and 0.046 mg/mL, respectively. In the concentration range of 2 to 50%, the extract was non-toxic to cells and was able to protect HaCaT cells from H2O2 damage. When the volume fraction of the extract was 20.96%, its anti-inflammatory ability reached 50%. These results demonstrated that the extract may be a safe and efficacious source for pharmaceutical or cosmetic applications, with Malassezia-inhibiting, antioxidant and anti-inflammatory activities.

Effects of molecular weight on intestinal anti-inflammatory activities of ß-D-glucan from Ganoderma lucidum.

To investigate the influence of molecular weight (M w) on the anti-inflammatory activity of ß-D-glucan from Ganoderma lucidum, ultrasonic irradiation was applied to treat the ß-D-glucan (GLP, 2.42 × 106 g/mol) solution to obtain two degraded fractions with molecular weight of 6.53 × 105 g/mol (GLPC) and 3.49 × 104 g/mol (GLPN). Structural analysis proved that the degraded fractions possessed similar repeated units with the original ß-D-glucan. The in vitro anti-inflammatory activity studies showed that all fractions could significantly inhibit LPS-induced expression of cytokines including TNF-α, IL-8, MIF and MCP-1 in Caco-2 cells at certain concentrations. Moreover, GLPC and GLPN exhibited better anti-inflammatory activity than GLPC. The intestinal anti-inflammatory activity evaluated by dextran sulfate sodium (DSS)-induced colitis mice model showed that intragastric administration of GLPN (lower M w fraction) could significantly recover inflamed tissues of mice. Compared with GLP and GLPC, GLPN exhibited stronger ability to inhibit the secretion of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6). The results revealed that M w of ß-D-glucan influenced its anti-inflammatory activity and decreasing of M w would improve the activity, which provided evidence for the potential use of ß-D-glucan from G. lucidum as anti-colitis ingredients.

Structural Characterization of a Polygonatum cyrtonema Hua Tuber Polysaccharide and Its Contribution to Moisture Retention and Moisture-Proofing of Porous Carbohydrate Material.

Porous carbohydrate materials such as tobacco shreds readily absorb moisture and become damp during processing, storage, and consumption (smoking). Traditional humectants have the ability of moisture retention but moisture-proofing is poor. Polygonatum cyrtonema Hua polysaccharide (PCP 85-1-1) was separated by fractional precipitation and was purified by anion exchange and gel permeation chromatography. The average molecular weight (Mw) of PCP 85-1-1 was 2.88 × 103 Da. The monosaccharide composition implied that PCP 85-1-1 consisted of fucose, glucose, and fructose, and the molar ratio was 22.73:33.63:43.65. When 2% PCP 85-1-1 was added to tobacco shreds, the ability of moisture retention and moisture-proofing were significantly enhanced. The moisture retention index (MRI) and moisture-proofing index (MPI) increased from 1.95 and 1.67 to 2.11 and 2.14, respectively. Additionally, the effects of PCP 85-1-1 on the aroma and taste of tobacco shreds were evaluated by electronic tongue and gas chromatography-mass spectrometry (GC-MS). These results indicated that PCP 85-1-1 had the characteristics of preventing water absorption under high relative humidity and moisturizing under dry conditions. The problem that traditional humectants are poorly moisture-proof was solved. PCP 85-1-1 can be utilized as a natural humectant on porous carbohydrates, which provides a reference for its development and utilization.

Effects of Oleic Acid Addition Methods on the Metabolic Flux Distribution of Ganoderic Acids R, S and T's Biosynthesis.

The effects of oleic acid addition methods on the metabolic flux distribution of ganoderic acids R, S and T's biosynthesis from Ganoderma lucidum were investigated. The results showed that adding filter-sterilized oleic acid in the process of submerged fermentation and static culture is of benefit to the synthesis of ganoderic acids R, S and T. The metabolic fluxes were increased by 97.48%, 78.42% and 43.39%, respectively. The content of ganoderic acids R, S and T were 3.11 times, 5.19 times and 1.44 times higher, respectively, than they were in the control group, which was without additional oleic acid. Ganoderic acids R, S and T's synthesis pathways (GAP), tricarboxylic acid cycles (TCA), pentose phosphate pathways (PP) and glycolysis pathways (EMP) were all enhanced in the process. Therefore, additional oleic acid can strengthen the overall metabolic flux distribution of G. lucidum in a submerged fermentation-static culture and it can reduce the accumulation of the by-product mycosterol. This study has laid an important foundation for improving the production of triterpenes in the submerged fermentation of G. lucidum.

Integrative Analysis of Selected Metabolites and the Fungal Transcriptome during the Developmental Cycle of Ganoderma lucidum Strain G0119 Correlates Lignocellulose Degradation with Carbohydrate and Triterpenoid Metabolism.

To systemically understand the biosynthetic pathways of bioactive substances, including triterpenoids and polysaccharides, in Ganoderma lucidum, the correlation between substrate degradation and carbohydrate and triterpenoid metabolism during growth was analyzed by combining changes in metabolite content and changes in related enzyme expression in G. lucidum over 5 growth phases. Changes in low-polarity triterpenoid content were correlated with changes in glucose and mannitol contents in fruiting bodies. Additionally, changes in medium-polarity triterpenoid content were correlated with changes in the lignocellulose content of the substrate and with the glucose, trehalose, and mannitol contents of fruiting bodies. Weighted gene coexpression network analysis (WGCNA) indicated that changes in trehalose and polyol contents were related to carbohydrate catabolism and polysaccharide synthesis. Changes in triterpenoid content were related to expression of the carbohydrate catabolic enzymes laccase, cellulase, hemicellulase, and polysaccharide synthase and to the expression of several cytochrome P450 monooxygenases (CYPs). It was concluded that the products of cellulose and hemicellulose degradation participate in polyol, trehalose, and polysaccharide synthesis during initial fruiting body formation. These carbohydrates accumulate in the early phase of fruiting body formation and are utilized when the fruiting bodies mature and a large number of spores are ejected. An increase in carbohydrate metabolism provides additional precursors for the synthesis of triterpenoids. IMPORTANCE Most studies of G. lucidum have focused on its medicinal function and on the mechanism of its activity, whereas the physiological metabolism and synthesis of bioactive substances during the growth of this species have been less studied. Therefore, theoretical guidance for cultivation methods to increase the production of bioactive compounds remains lacking. This study integrated changes in the lignocellulose, carbohydrate, and triterpenoid contents of G. lucidum with enzyme expression from transcriptomics data using WGCNA. The findings helped us better understand the connections between substrate utilization and the synthesis of polysaccharides and triterpenoids during the cultivation cycle of G. lucidum. The results of WGCNA suggest that the synthesis of triterpenoids can be enhanced not only through regulating the expression of enzymes in the triterpenoid pathway, but also through regulating carbohydrate metabolism and substrate degradation. This study provides a potential approach and identifies enzymes that can be targeted to regulate lignocellulose degradation and accelerate the accumulation of bioactive substances by regulating substrate degradation in G. lucidum.

Development and Optimization of the Triterpenoid and Sterol Production Process with Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum Strain G0017 (Agaricomycetes), in Liquid Submerged Fermentation at Large Scale.

Ganoderma lucidum mycelia are rich in active substances such as triterpenoids and sterols. However, reports on the development of effective submerged fermentation processes are lacking and the resulting total triterpene and sterol yield is still quite low. In this study, a new G. lucidum strain G0017 mycelium isolated by screening was studied in a 3-L fermenter to investigate the effect of aeration rate in liquid submerged fermentation production of triterpenoids and sterols. By fitting the specific mycelial growth rate and the specific production rate of the triterpenoid and sterol model, an effective multistage aeration rate control process for triterpenoid and sterol fermentation production was developed. This process was validated and proven in 3-L and 50-L fermenters. The resulting yields of triterpenoids and sterols were 3.34 and 3.46 g/L, respectively, which were 69.54% and 75.63% higher than the fixed aeration rate of 1.50 volume of air per volume of liquid per minute. This optimized fermentation production process conceivably could be applied to larger-scale industrial production and perhaps also to improve liquid submerged fermentation processes with relevant edible and medicinal mushrooms.

Structure and chain conformation of bioactive ß-D-glucan purified from water extracts of Ganoderma lucidum unbroken spores.

Two polysaccharide fractions (GLSB50 and GLSB70) with total sugar content of 82.07 wt% and 53.79 wt%, respectively, were obtained from the water extracts of unbroken Ganoderma lucidum spores by sequential ethanol precipitation treatment. Compared with GLSB70, GLSB50 exhibited better activity on stimulation of humoral immune responses in immunosuppressed mice. A novel ß-D-glucan (GLSB50A-III-1) with weight average molecular weight (Mw) of 1.93 × 105 g/mol was purified from GLSB50 through chromatography separation. The exponent α value of Mark-Houwink-Sakurada equation was calculated to be 0.13, indicating that GLSB50A-III-1 presented globular spheres conformation in aqueous solution. Structural analysis showed that GLSB50A-III-1 mainly consisted of (1 â†’ 3), (1 â†’ 4), (1 â†’ 6)-linked ß-d-glucose residues in the backbone, with two single ß-D-Glcp attached at O-6 of ß-(1 â†’ 3) and ß-(1 â†’ 4)-linked residues separately as side chains. The repeat unit of GLSB50A-III-1 was deduced as follows.

Simultaneous Determination of 13 Organic Acids in Liquid Culture Media of Edible Fungi Using High-Performance Liquid Chromatography.

The study aimed at detecting 13 organic acids (oxalic acid, maleic acid, citric acid, tartaric acid, malic acid, quinic acid, succinic acid, fumaric acid, formic acid, acetic acid, propionic acid, isobutyric acid, and butyric acid) by establishing a high-performance liquid chromatography (HPLC). The analysis was performed using two sugar columns, i.e., SH1011 column and KC-811 column. The optimal conditions were as follows: 4 mmol/L HClO4 solution as the eluent with UV-visible detector (210 nm), a flow rate of 1 mL/min at the temperature of 60°C, and the injection volume at 10 µL. The results showed that all the calibration curves had excellent linearity (R 2 > 0.9991) within the test ranges. The RSD values of the thirteen analytes were lower than 2.94% at three levels, the recoveries were 91.9%-102.0%, the limit of detection (LOD) was between 0.05 and 10.63 µg/mL, and the quantification (LOQ) was between 0.10 and 19.53 µg/mL. Finally, the proposed methodology was successfully applied for the analysis of organic acids in the culture medium of edible fungi. In conclusion, the study findings proved that the method was sensitive, accurate, reproducible, and could be readily applied to analyze the organic acids in the samples.

A Study on the Antioxidant Properties and Stability of Ergothioneine from Culinary-Medicinal Mushrooms.

The naturally occurring amino acid ergothioneine (EGT) has excellent free radical scavenging ability, which was not different to ascorbic acid. The IC50 values for EGT scavenging hydrogen peroxide, hydroxyl radicals, and superoxide anions were 11.65 ± 0.31, 70.31 ± 1.59, and 160.44 ± 0.32 µg/mL, respectively. The EGT concentration in different species of mushrooms was significantly different (p < 0.05), but it was not significantly related to the ability of the mushrooms to scavenge reactive oxygen species (p > 0.05). After isolating EGT from mushrooms, we demonstrated that the antioxidant ability of EGT accounts for about 25% of the total antioxidant ability of the extract. We studied the stability of EGT and found that it has excellent light, thermal, and acid-base stability. However, the presence of Cu2+ decreased the concentration of EGT. Unlike EGT, the thermal stability of the EGT extracted from Pleurotus citrinopileatus (PEGT) was not as good as EGT, while long-term high-temperature heating caused a decrease in the concentration of PEGT. The results of our study provide a basis for further investigating EGT from mushrooms for research and development.

Cordycepin inhibits pancreatic cancer cell growth in vitro and in vivo via targeting FGFR2 and blocking ERK signaling.

Cordycepin (3'-deoxyadenosine) from Cordyceps militaris has been reported to have anti-tumor effects. However, the molecular target and mechanism underlying cordycepin impeding pancreatic cancer cell growth in vitro and in vivo remain vague. In this study, we reported functional target molecule of cordycepin which inhibited pancreatic cancer cells growth in vitro and in vivo. Cordycepin was confirmed to induce apoptosis by activating caspase-3, caspase-9 and cytochrome c. Further studies suggested that MAPK pathway was blocked by cordycepin via inhibiting the expression of Ras and the phosphorylation of Erk. Moreover, cordycepin caused S-phase arrest and DNA damage associated with activating Chk2 (checkpoint kinase 2) pathway and downregulating cyclin A2 and CDK2 phosphorylation. Very interestingly, we showed that cordycepin could bind to FGFR2 (KD = 7.77 × 10-9) very potently to inhibit pancreatic cancer cells growth by blocking Ras/ErK pathway. These results suggest that cordycepin could potentially be a leading compound which targeted FGFR2 to inhibit pancreatic cells growth by inducing cell apoptosis and causing cell cycle arrest via blocking FGFR/Ras/ERK signaling for anti-pancreatic cancer new drug development.

Regioselective sulfation of ß-glucan from Ganoderma lucidum and structure-anticoagulant activity relationship of sulfated derivatives.

In the present study, regioselective sulfation of ß-glucan (GLP) from Ganoderma lucidum were firstly established by using 4,4'-dimethoxytrityl chloride and hexamethyldisilazane as protecting precursor. 2,4,6-O-sulfated, 6-O-sulfated and 2,4-O-sulfated GLP derivatives were prepared and the molecular weights (Mw) of derivatives were determined to range from 0.94 × 104 to 6.27 × 104 g/mol, while the degrees of sulfation (DS) were calculated to vary from 0.83 to 1.74. The regioselective sulfation of GLP was confirmed by FT-IR, 13C NMR spectroscopy and methylation analysis. Results indicated that the sulfated substitution sites were predominantly at C-6 in 6-O-sulfated GLP (S6-OGLP) and C-4 in 2,4-O-sulfated GLP (S2,4-OGLP), respectively. Clotting assays (APTT, PT and TT) in vitro showed that sulfate groups were essential for anticoagulant activity and S6-OGLP exhibited much higher than others. Meanwhile, sulfated GLP with higher DS and Mw showed stronger anticoagulant activity in the case of the same condition.

Comparative Analysis of Triterpene Composition between Ganoderma lingzhi from China and G. lucidum from Slovakia under Different Growing Conditions.

The mushroom today known as Ganoderma lingzhi has been used for centuries in the countries of Eastern Asia as a very important medicinal mushroom. It prefers growing on rotten wood of broadleaf trees and is mainly distributed in the tropics and subtropics. Its relative G. lucidum occurs naturally almost all the Earth, and it colonizes mostly oak and beech trees in Central Europe. G. lingzhi and G. lucidum are similar species. To obtain the qualitative parameters of G. lingzhi and G. lucidum, several strains (five G. lingzhi strains and five G. lucidum ones) were chosen and cultivated in both Slovakia and China, using wood chip (beech and oak) substrate and liquid fermentation method, respectively. It was found that there were more low-polarity triterpenes in G. lucidum, while G. lingzhi contained more high-polarity triterpenes. Beech substrate was more suitable for the accumulation of triterpenes in solid cultivation for both strains of G. lucidum and G. lingzhi. Strain C4 of G. lingzhi and strain K2 of G. lucidum contained higher triterpenes in either mycelium or fruiting bodies. Data in this study can help to identify these two species and bring a great benefit to the production of bioactive compounds of G. lucidum from Slovakia.

Polysaccharide of Ganoderma and Its Bioactivities.

Ganoderma, named lingzhi in China, has been used for centuries as drug and nutraceutical to treat diseases. Based on our research and other literatures, the chapter summarizes the progress of preparation, structural features and properties, bioactivities of Ganoderma polysaccharides. The aim is to provide a comprehensive source of information for researchers and consumers of Ganoderma, so they can better understand Ganoderma polysaccharides and their biological activities. In addition, more clinical studies should be carried out to meet the criteria for new drug development, and more convincing scientific data should be provided. In addition, on the basis of a large number of studies on Ganoderma polysaccharides, we suggest that more clinical studies should be carried out so that Ganoderma can be better recognized and applied all over the world.

Optimization of Ganoderma lucidum Polysaccharides Fermentation Process for Large-Scale Production.

The objective of this study was to increase the intracellular polysaccharide yield of Ganoderma lucidum. The accordingly optimized fermentation medium by central composite design method contains glucose 40 g L-1, yeast powder 12 g L-1, potassium dihydrogen phosphate 3 g L-1, initial pH 5.5, and inoculum size 10 mL 100 mL-1. Under this condition, the predicted value of intracellular polysaccharide yield was 2.03 g L-1. Shake flask experiments confirmed that the average intracellular polysaccharide yield was 1.98 g L-1 similar to the predicted value. The yields of intracellular polysaccharides in the 5-L and 50-L fermentors were 2.59 g L-1 and 2.65 g L-1, respectively. The molecular weight distribution of intracellular and extracellular polysaccharides obtained was determined by HPSEC-MALLS-RI. The results showed that the weight-average molecular weight of component 1 in the intracellular crude polysaccharide was 4.695 × 106 Da and the mass fraction was 58%. The weight-average molecular weight of component 2 in the extracellular polysaccharide was 5.554 × 104 Da. The mass fraction was 94.9%. The liquid submerged fermentation process of G. lucidum mycelium obtained from this study has effectively increased the yield of intracellular polysaccharides. Its intracellular and extracellular polysaccharides have good immunological activity. Conceivably, the optimized process can be applied for the large-scale production.

Chemical Compounds and Antioxidant Activity of Volatile Oil from the White Jelly Mushroom, Tremella fuciformis (Tremellomycetes).

To fully analyze the composition of volatile oil extracted from Tremella fuciformis, hydrodistillation (HD) and solid phase microextraction (SPME) were adopted simultaneously. In both cases, the analysis was carried out using gas chromatography-mass spectrometry and the antioxidant activity of the volatile oil was determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method with rutin as a positive control. Nineteen components in HD and 68 components in SPME were identified, respectively. Moreover, the oil obtained from T. fuciformis by HD indicated that aromatic compounds were a major class (93.5%), followed by the terpenes (5.7%), alkanes (0.4%), and alcohols (0.3%). Among them, butylated hydroxytoluene was the highest concentration (92.5%) of the compounds. The compounds detected by SPME were different from those of HD, and the substances with the largest content were esters (57.7%), followed by alcohols (19.0%), acids (7.0%), and aldehydes (6.3%). Only three of the same substances were detected in both of them, namely borneol, (-)-α-terpineol, and acetic acid. In the DPPH assays, strong antioxidant activity (IC50 = 0.176 mg/mL) was evident in volatile oil from T. fuciformis. Antioxidant activity was positively correlated with the concentration of volatile oil.

Dissolution of Bioactive Components from Dried Fruiting Bodies of the Culinary-Medicinal Shiitake Mushroom, Lentinus edodes (Agaricomycetes), during Cleaning, Soaking, and Cooking.

Lentinus edodes fruiting bodies are rich in active substances such as polysaccharides and eritadenine. Patients with gout, however, should avoid or severely limit their intake of foods containing large amounts of purine. In this study we quantitatively analyzed the polysaccharide and purine compounds dissolved from L. edodes fruiting bodies during cleaning, soaking, and cooking. Eritadenine, adenosine, guanosine, guanosine monophosphate, adenosine monophosphate, xanthine, and adenine dissolved from L. edodes fruiting bodies during cleaning with tap water; their dissolution rates ranged between 3.77% and 24.30%. Dissolution rates of polysaccharide and purine compounds in L. edodes fruiting bodies increased linearly with increases in the duration of soaking and cooking, and adding acetic acid or NaHCO3 in the soaking or cooking solutions significantly either inhibited or promoted their dissolution rates. On the basis of these experimental results, we offer science-based suggestions for reasonable treatment of L. edodes fruiting bodies before eating for both patients with gout and healthy people.

Effect of Culture Time on the Bioactive Components in the Fruit Bodies of Caterpillar Mushroom, Cordyceps militaris CM-H0810 (Ascomycetes).

Cordyceps militaris are widely cultivated in China for an important raw material for health foods. CM-H0810 is a C. militaris strain used in the production of C. militaris in Shanghai, the surrounding areas of Shanghai, and Guangdong province in China. We evaluated the effect of culture time on the bioactive components in the fruit bodies of C. militaris CM-H0810 to provide scientific references for production of C. militaris fruit bodies with good quality. The results showed that the polysaccharide contents increased gradually during 35-45 d, but it declined with the prolongation of culture time. The highest polysaccharide content was 3.46% at 45 d. With the prolongation of culture time the cordycepin content gradually increased; the highest cordycepin content was 3.57 µg/mg at 60 d, which increased 321% compared to that at 35 d. Contrary to cordycepin, the adenosine content declined gradually, with the highest content of 1.86 µg/mg at 35 d and the lowest content of 1.48 µg/mg at 60 d. Our study indicates that it is necessary to select suitable harvest times in view of different compounds that are desirable to obtain in high quantities.

Triterpenes and Soluble Polysaccharide Changes in Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), During Fruiting Growth.

We analyzed the changes in triterpenes and soluble polysaccharides in Ganoderma lucidum strain G0119 during 4 growth phases in 3 regions of the fruiting bodies using reversed-phase high-performance liquid chromatography, and we also analyzed the soluble polysaccharides using high-performance size-exclusion chroma-tography-multiple-angle laser-light scattering refractive index analysis. The strong polar triterpenes decreased while weak polar triterpenes increased during the growth cycle of G. lucidum. The highest contents of ganoderic acid B, ganoderic acid A, and ganoderenic acid B were detected in the stipe during phase II, and ganoderic acid S, ganoderic acid T, and ganoderiol B peaked in the base during phase IV. The total content of soluble polysaccharides in samples decreased after the primordium developed into a fruiting body. Two high-molecular-weight fractions were detected in the soluble polysaccharide samples: α-l,4-glucan and ß-l,3-glucan, respectively. They were primarily distributed in the pileus during phase II, and both decreased after this phase. These results led us to select a more suitable growth phase and region for harvesting to obtain extracts with higher contents of triterpenes and soluble polysaccharides.

Structural characterization of a bioactive water-soluble heteropolysaccharide from Nostoc sphaeroids kütz.

A water soluble Nostoc sphaeroids kütz polysaccharide (NSKP) was extracted and purified by precipitating hot-water extract from Nostoc sphaeroids kütz with 40% (v/v) ethanol. The yield was 40.10% (w/w), and weight average molecular weight (Mw) was determined as 1.31 × 105 g/mol. Cell culture study showed that NSKP could stimulate the NO release from RAW264.7 macrophages. The ρ value (Rg/Rh) of NSKP was calculated as 1.50, indicating flexible random coils conformation of NSKP in aqueous solution. According to methylation analysis, and 1D & 2D NMR spectra, the molecular structure of polysaccharide NSKP was deduced as below.