Effect of Different Carbon Sources on Antioxidant Properties of Exopolysaccharides Produced by Scleroderma areolatum (Agaricomycetes).

Five kinds of exopolysaccharides (EPS) were obtained by fermentation of Scleroderma areolatum Ehrenb. with sucrose, glucose, maltose, lactose, and fructose as carbon sources. Antioxidant abilities of the obtained EPSs were evaluated by inhibiting AAPH, HO·, and glutathione (GS·) induced oxidation of DNA and quenching 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS· and galvinoxyl radicals. The effects of carbon sources on the antioxidant properties of EPSs could be examined. The results showed that five EPSs can effectively inhibit radicals induced oxidation of DNA, and the thiobarbituric acid reactive substances (TBARS) percentages were 44.7%-80.8%, 52.3%-77.5%, and 44.7%-73.3% in inhibiting AAPH, HO·, and GS· induced oxidation of DNA, respectively. All five EPSs could scavenge ABTS· and galvinoxyh, and exhibit superior activity in scavenging free radicals. Antioxidant abilities of EPS with fructose as carbon source were highest among five EPS.

Aspercitrininone A, novel antibacterial polyketide featuring unusual spiral skeleton from Aspergillus cristatus.

Aspercitrininone A (1), a novel polyketide featuring an unprecedented tetracyclic 6/6/6/5 spiral skeleton, was obtained from the rice fermentation cultures of the fungus Aspergillus cristatus together with five known compounds (2-6). Their structures were determined by HRESIMS data, 1D and 2D NMR spectroscopic analysis, and electronic circular dichroism (ECD) calculations. Aspercitrininone A was revealed as a new type of C/D cycle spiral structure and an unusual addition product of o-quinoid form citrinin with 2-methylterrefuranone. Compounds 1, 4, and 5 exhibited potent antibacterial activities with minimal inhibitory concentration (MIC) values from 13.2 to 67.3 µg/mL against four strains of human pathogenic bacteria in vitro.

Structure Characterization and Anti-Inflammatory Activity of Polysaccharides from Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Agaricomycetes) by Microwave-Assisted Freeze-Thaw Extraction.

A water-soluble polysaccharide (GLP-2) was isolated and purified from Ganoderma lucidum by the microwave-assisted freeze-thaw method. Microwave-assisted rapid thawing treatment can greatly improve the extraction yield of polysaccharides. The chemical structure of GLP-2 was analyzed with FT-IR, HPLC, GC-MS, and NMR spectrometry. It was proved that GLP-2 is mainly composed of ß-1,3-glucose and ß-1,6-glucose. The chain conformation of GLP-2 was analyzed by SEC-MALLS-RI, indicating that GLP-2 adopts semi-rigid chain conformation. Its molecular weight is 16.7 × 104, and its molecular size is about 61.2 nm. MTT assay indicated that GLP-2 was non-toxic to RAW 264.7 cells in vitro. The results of anti-inflammatory studies showed that GLP-2 can inhibit the production of NO, TNF-α, IL-1ß, and IL-6 in RAW 264.7 macrophage stimulated by lipopolysaccharide (LPS). The above data showed that the extraction method used in this study can obtain a high-yield polysaccharide with anti-inflammatory activity.

Novel kojic acid derivatives with anti-inflammatory effects from Aspergillus versicolor.

Two novel kojic acid derivatives, kojicones A and B (1 and 2), along with the precursors kojic acid (3) and (2R,4R)-4-hydroxy-5-methoxy-2,4-dimethyl-2- [(2R)-2-methylbutyryloxy]-5-cyclohexen-1,3-dione (4), were isolated from a fungal strain Aspergillus versicolor. Their structures and absolute configurations were accurately confirmed by HRESIMS data, NMR analysis, and electronic circular dichroism (ECD) calculations. Kojicones A and B were the first examples of kojic acid adducts with cyclohexen-1,3-dione possessing unprecedented tricycle skeletons. Compounds 1-3 were found to have inhibition on the NO production of murine RAW 264.7 cells. They can also reduce the mRNA expression of four cytokines (IL-6, IL-1ß, TNF-α, and iNOS) and promote the expression of IL-4 at 20 µM. Moreover, kojic acid (3) could treat the DSS (dextran sulfate sodium)-induced colitis on mice with the effectiveness similar to that of the positive control. The results suggested that kojic acid and its derivatives could be a promising anti-inflammatory source for the medicinal and cosmetic industry.

Effect of Carbon Source on Properties and Bioactivities of Exopolysaccharide Produced by Trametes ochracea (Agaricomycetes).

The effects of carbon source on properties and bioactivities of exopolysaccharide (EPS) produced by Trametes ochracea were investigated in this study. The results indicated that EPS production varied with five different carbon sources. After a fermentation period of 8 days, sucrose was the most suitable carbon source for biomass and EPS production. The predominant carbohydrate compositions in EPSs identified were glucose and mannose. The EPS fermented by sucrose has the highest glucose content. Then, FT-IR spectral analysis revealed prominent characteristic groups in EPSs. Each particular EPS possessed the specific bands at 808-809 cm-1 and 914-922 cm-1, indicating both α- and ß-configurations of the sugar units. Furthermore, thermogravimetric analysis (TGA) indicated the EPS with sucrose and glucose as carbon source showed different degradation behavior compared with the other three EPSs. The variation also affects antioxidant and antihyperlipemia activities investigated using hydroxyl and DPPH radical scavenging assay, and in hyperlipemia mice. Sucrose was the best carbon source from the viewpoint of OH and DPPH radical scavenging activities, and antihyperlipemia activity, probably due to the relatively high glucose content in EPS.

Proteoglycan isolated from Corbicula fluminea exerts hepato-protective effects against alcohol-induced liver injury in mice.

Corbicula fluminea (Asian clam), a freshwater bivalve mollusk, has been consumed in China for centuries as a health food and traditional Chinese medicine for treating liver diseases and alcoholism. This study aimed to evaluate the hepato-protective effects and potential mechanisms of a proteoglycan (PSP) from C. fluminea on alcohol-induced liver injury in mice. Results showed that PSP pretreatment significantly antagonized the increases in serum alanine aminotransferase, aspartate aminotransferase, triacylglycerides, and hepatic malondialdehyde levels; elevated the antioxidant enzyme activities and hepatic glutathione levels; and suppressed the levels of hepatic inflammatory cytokines in alcohol-induced liver injury in mice (P < 0.05). Histopathological observation further revealed the potential hepato-protective effect of PSP against alcohol damage. Particularly, PSP pretreatment resulted in significantly decreased expression of cytochrome P450 2e1 (CYP2E1) while significantly upregulating the expression of hemeoxygenase-1 (HO-1) (P < 0.05). These results suggested that PSP could protect the liver from hepatocyte injury induced by alcohol possibly by alleviating hepatic lipid metabolism, elevating antioxidant-enzyme activity, suppressing the immune inflammatory response, and reversing the expression levels of CYP2E1 and HO-1. Therefore, PSP may be developed as a food supplement that can be used to prevent liver diseases.

Pectin-decorated selenium nanoparticles as a nanocarrier of curcumin to achieve enhanced physicochemical and biological properties.

In this study, the authors developed pectin-stabilised selenium nanoparticles (pectin-SeNPs) for curcumin (Cur) encapsulation and evaluated their physicochemical properties and biological activities. Results showed that pectin-SeNPs and Cur-loaded pectin-SeNPs (pectin-SeNPs@Cur) exhibited monodisperse and homogeneous spherical structures in aqueous solutions with mean particle sizes of ∼61 and ∼119 nm, respectively. Cur was successfully encapsulated into pectin-SeNPs through hydrogen bonding interactions with an encapsulation efficiency of ∼60.6%, a loading content of ∼7.4%, and a pH-dependent and controlled drug release in vitro. After encapsulation was completed, pectin-SeNPs@Cur showed enhanced water solubility (∼500-fold), dispersibility, and storage stability compared with those of free Cur. Moreover, pectin-SeNPs@Cur possessed significant free radical scavenging ability and antioxidant capacity in vitro, which were stronger than those of pectin-SeNPs. Antitumour activity assay in vitro demonstrated that pectin-SeNPs@Cur could inhibit the growth of HepG2 cells in a concentration-dependent manner, and the nanocarrier pectin-SeNPs exhibited a low cytotoxic activity against HepG2 cells. Therefore, the results suggested that pectin-SeNPs could function as effective nanovectors for the enhancement of the water solubility, stability, and in vitro bioactivities of hydrophobic Cur.

Characterization and Antioxidant Activity of an Exopolysaccharide Produced by Rigidoporus microporus (Agaricomycetes).

In this investigation we developed an optimal fermentation medium to produce an exopolysaccharide (EPS) with antioxidant activity from Rigidoporus microporus. Lactose and tryptone were chosen as the optimal carbon and nitrogen sources, respectively, for EPS production, with a 6-day cultivation cycle. After removing proteins through the use of the Sevag method, one EPS fraction was purified from the culture filtrates by gel filtration chromatography on a Sepharose CL-6B column. The preliminary chemical structure of the EPS fraction was determined by Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance. The results indicated that the main structure of the EPS consisted of ß-glucopyranose and mannopyranose. Furthermore, conformational parameters such as molecular weight (Mw), intrinsic viscosity ([η]), mean-square radii of gyration (Rg), and hydrodynamic radius (Rh) of the EPS were characterized using a size exclusion chromatography-multiangle light scattering-refractive index viscometry method. It showed that the EPS was a kind of water-soluble polysaccharide with a moderate molecular weight (34.1 × 104) and a flexible, linear random coil chain structure. The antioxidant activity tests suggested that the EPS has great potential application as a natural antioxidant material in foods and medicines.

Molecular Characterization of Two Polysaccharides from Phellinus vaninii Ljup and their Cytotoxicity to Cancer Cell Lines.

BACKGROUND: Phellinus vaninii, a medicinal basidiomycete fungus, is often confused with Phellinus igniarius and Phellinus linteus. Polysaccharides extract from P. igniarius and P. linteus are reported to stimulate humoral immunity and inhibit tumor growth However, available literature reviewed no information on the relationship between bioactivities and structures of polysaccharides from the fruit body of P. vaninii. METHODS: Two water-soluble polysaccharides (PV-W, PV-B) were isolated and purified from fruiting bodies of P. vaninii by hot water and sodium hydroxide solution, respectively. The chemical structures of PV-W, PV-B were analyzed by FT-IR, GC-MS analysis and 13C NMR spectra. And, their molecular conformations were analyzed by viscosity method and SEC-MALLS-RI. Finally, their inhibition of cancer cells was investigated using MTT assay. RESULTS: The results illustrated that PV-W was a heteropolysaccharide, mainly composed of mannose, glucose, arabinose and galactose. PV-B was a ß-1, 3-D-glucan branched with ß-1, 6-D-glucose. The results of viscometry proved that PV-W and PV-B could be molecularly dispersed in water without aggregation. The results of SECMALLS- RI indicated that the two polysaccharides had the similar Mw but different molecular conformation. That is, PV-W existed as a stable globular shape, while PV-B presented a more expanded flexible random coils conformation. MTT assay indicated that PV-B showed higher inhibition effect on HepG2 and HeLa cells than PV-W in vitro. CONCLUSION: This work provided the important information of active components from P. vaninii and its potential applications in the food and medicine industry.

Characterization and Antiproliferative Effect of Novel Acid Polysaccharides from the Spent Substrate of Shiitake Culinary-Medicinal Mushroom Lentinus edodes (Agaricomycetes) Cultivation.

In this study, a high yield of crude polysaccharide (16.73 ± 0.756%) was extracted from the spent mushroom substrate of Lentinus edodes using a hot alkali extraction method. Two groups of polysaccharides (designated as LSMS-1 and LSMS-2) were obtained from the crude extract by size exclusion chromatography (SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index detector system. The weight-average molar masses of LSMS-1 and LSMS-2 were determined to be 6.842 × 106 and 2.154 × 106 g/mol, respectively. The SEC/MALLS analysis revealed that the molecular shapes of LSMS-1 and LSMS-2 were sphere-like forms in aqueous solution. Carbohydrate composition analysis using chromatography--mass spectrometry revealed that they were both acid heteropolysaccharides. LSMS-1 comprised mainly glucose and galacturonic acid, whereas LSMS-2 mainly consisted of xylose and glucuronic acid. Fourier transform infrared spectral analysis of the purified fractions revealed typical characteristic polysaccharide groups. In addition, MTT assays with refined polysaccharide doses of 25, 50, 100, 200, and 400 µg/mL suggested that both of the polysaccharide fractions exhibited antiproliferative activity against 6 tested human tumor cell lines in a concentration-dependent manner, and LSMS-2 had better anticancer capacity in vitro than LSMS-1. The inhibition ratio of LSMS-2 against A549 human lung cancer cells, the SGC7901 gastric cancer cell line, MCF-7 breast cancer cells, the U937 histiocytic lymphoma cell line, and the MG-63 human osteosarcoma cell line reached 43.55%, 29.97%, 19.63%, 18.24%, and 17.93%, respectively, at a concentration of 400 µg/mL.

Preparation and Bioactivity of Exopolysaccharide from an Endophytic Fungus Chaetomium sp. of the Medicinal Plant Gynostemma Pentaphylla.

BACKGROUND: Many exopolysaccharides from the endophytes in medicinal plants possess various potential bioactivities. MATERIALS AND METHODS: The endophytic fungus JY25 was isolated from the leave of the Chinese medicinal plant Gynostemma pentaphylla and identified as Chaetomium sp. by its phylogenetic and physiological analysis. One exopolysaccharide (EPS) fraction was isolated from the fermentation broth by ethanol precipitation and purified by gel filtration chromatography on Sepharose CL-6B. The molecular characteristics were examined by GC-MS, FT-IR, and multiangle laser light scattering (MALLS). RESULTS: The monosaccharide composition analysis indicated that the purified EPS was mainly composed of glucose, mannose, arabinose, and galactose with the molecular ratio of 78.29: 8.99: 8.64: 4.08. FT-IR spectral analysis of the purified EPS revealed prominent characteristic groups, such as carbonyl bond, pyranose ring, and so on. The weight-average molar mass and the polydispersity ratio of the EPS were revealed to be 1.961×104 g/mol and 1.838, respectively. Furthermore, thermo gravimetric analysis (TGA) indicated that the degradation temperature of the purified EPS was 305° C. The purified EPS from the endophytic fungus Chaetomium sp. displayed antioxidant and antiproliferative activities. CONCLUSION: The results demonstrated that the EPS could be used as a healthful food and material source in pharmaceutical industries. SUMMARY: An exopolysaccharides (EPS) with antioxidant and antiproliferative activities from an endophytic fungus Chaetomium sp. was reported. Abbreviations used: ANOVA: Analysis of variance; DPPH: 2,2-diphenyl-1-picrylhydrazyl; EPS: Exopolysaccharide; FT-IR: Fourier transform infrared spectroscopy; GC-MS: Gas chromatography-mass spectrometry; Mw: Mass weight; MALLS: Multiangle laser light scattering; SEC: Size Exclusion Chomatography; SPSS: Statistical Package of the Social Science; TGA: Thermo gravimetric analysis; TFA: Trifluoroacetic acid.

Sulfation of the Extracellular Polysaccharide Produced by the King Oyster Culinary-Medicinal Mushroom, Pleurotus eryngii (Agaricomycetes), and Its Antioxidant Properties In Vitro.

Extracellular polysaccharide from Pleurotus eryngii was sulfated; the optimum reaction conditions used pyridine as the reaction solvent, a temperature of 80°C, and a reaction time of 90 minutes. The structure and antioxidant activity of the sulfated and original polysaccharides (designated as SF-1 and Fr-1, respectively) were investigated. The main functional groups of polysaccharides were determined by Fourier transform infrared, and the chain conformation was determined by size-exclusion chromatography with laser light scattering and viscometry. Fourier transform infrared spectra indicated that the sulfated group was linked to the polymer. The molecular weight of SF-1 was much lighter than that of Fr-1, which suggested that degradation occurred during sulfation. The stable globular shape conformation of Fr-1 was changed to the random coil conformation of SF-1 in the aqueous solution. Moreover, the sulfated derivative SF-1 was found to have a better scavenging ability on hydroxyl radicals and DPPH free radicals than Fr-1. It seems that the chemical modification of P. eryngii polysaccharides by sulfation effectively enhances their antioxidant activity.

Effect of Carbon Source on Properties and Antioxidant Potential of Exopolysaccharides Produced by Trametes robiniophila (Higher Basidiomycetes).

The effects of carbon source on properties and antioxidant potential of exopolysaccharides (EPS) produced by Trametes robiniophila were investigated in this study. The results indicated that the EPS production varied with five different carbon sources. The predominant carbohydrate compositions in EPSs identified were glucose and mannose. Then, FT-IR spectral analysis revealed prominent characteristic groups in the EPSs. Furthermore, thermogravimetric analysis (TGA) indicated the EPS with lactose as the carbon source showed different degradation behavior as compared to the other four EPSs, probably due to larger ribose content as one of major monosaccharides in the EPS. The variation also affects the antioxidant activities investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was the best carbon source from the viewpoint of antioxidant activity due to the relatively high xylose content in the EPS.

Characterization of a novel thermophilic phospholipase B from Thermotoga lettingae TMO: applicability in enzymatic degumming of vegetable oils.

A novel phospholipase B (TLPLB) from Thermotoga lettingae TMO has been cloned, functionally overexpressed in Escherichia coli and purified to homogeneity. Gas chromatography indicated that the enzyme could efficiently hydrolyze both the sn-1 and sn-2 ester bonds of 1-palmitoyl-2-oleoyl phosphatidylcholine as phospholipase B. TLPLB was optimally active at 70 °C and pH 5.5, respectively. Its thermostability is relatively high with a half-life of 240 min at 90 °C. TLPLB also displayed remarkable organic solvent tolerance and maintained approximately 91-161 % of its initial activity in 20 and 50 % (v/v) hydrophobic organic solvents after incubation for 168 h. Furthermore, TLPLB exhibited high degumming activity towards rapeseed, soybean, peanut and sunflower seed oils, where the phosphorus contents were decreased from 225.2, 189.3, 85.6 and 70.4 mg/kg to 4.9, 4.7, 3.2 and 2.2 mg/kg within 5 h, respectively. TLPLB could therefore be used for the degumming of vegetable oils.

Optimization, Purification, Characterization, and Antioxidant Activity of Exopolysaccharide Produced by the Northern Tooth Mushroom, Climacodon septentrionalis (Basidiomycota).

The optimization, purification, and characterization of exopolysaccharide (EPS) from Climacodon septentrionalis were investigated. The results showed that the optimal incubation time was 8 days for EPS production by C. septentrionalis; maltose and soy extract were the best carbon and nitrogen sources, respectively. One kind of EPS fraction was purified; it had a molecular weight of about 3.4 × 10(5) Da and mainly comprised glucose (98%). The main structure of EPS is α-glucopyranose. In addition, the EPS showed good antioxidant properties in vitro. The thermal stability of EPS also was investigated, and the results suggest that to maintain its bioactivity the processing temperature of EPS should not be more than 200°C. The structural characteristics of EPS, such as molecular weight, functional groups, monosaccharide constituents, and configuration of the glycosidic bond give EPS great potential for application as a natural antioxidant material in health, food, and therapeutics.

Mycelial fermentation characteristics and anti-fatigue activities of a Chinese caterpillar fungus, Ophiocordyceps sinensis strain Cs-HK1 (Ascomycetes).

Mycelial fermentation of an Ophiocordyceps sinensis strain Cs-HK1 was carried out in various volumes of stirred-tank fermenters from 1.6-L and 15-L laboratory scale to 2000-L industrial scale. The mycelial growth in most fermenters had a higher rate, due probably to more efficient oxygen supply, than in shake-flasks. The mycelial fermentation was successfully scaled up to 2000-L industrial fermenters, achieving 30 g/L maximum biomass in 5 days. The Cs-HK1 mycelia formed hairy and fluffy pellets in the fermentation medium and the mycelial broth exhibited pseudoplastic rheology following the power law, with the flow behavior index n decreasing from 0.5 to 0.3, and the flow consistency K and the apparent viscosity µα increasing with time and biomass concentration. The mycelial broth containing biomass and extracellular products harvested from 2000-L fermenters was tested for anti-fatigue activities in forced animal swimming experiments. The mycelium hot water extract showed the most significant effects, increasing the swimming endurance of mice up to 100%, and also increasing the glycogen levels and reducing the lactic acid and blood urea nitrogen levels significantly. The results demonstrated the feasibility of Cs-HK1 mycelial fermentation for large-scale production of bioactive and medicinal materials.

Production of extracellular polysaccharides by the medicinal mushroom Trametes trogii (higher Basidiomycetes) in stirred-tank and airlift reactors.

Extracellular polysaccharides (EPSs) produced by submerged culture of Trametes trogii exhibit antioxidant and antitumor activities. In this study, mycelial growth and EPS production of T. trogii were investigated using optimal culture conditions (maltose [53.12 g/L] and polypeptone [4.21 g/L] in distilled water) in a 5-L jar fermenter. Maximum biomass growth (10.81 g/L) occurred after 5 days of cultivation, whereas maximal EPS yield (1.86 g/L) was achieved after 5 days in a 5-L stirred-tank reactor. Furthermore, the morphological parameters (i.e., mean diameter, circularity, roughness, and compactness) of the pellets and the viscosity of the broth were characterized. It was proved that the compactness of the pellets were significantly positively correlated with EPS content.

Production, purfication, molecular characterization and bioactivities of exopolysaccharides produced by the wine cap culinary-medicinal mushroom, Stropharia rugosoannulata 2# (higher Basidiomycetes).

The optimal culture conditions of exopolysaccharides (EPS) production in submerged culture medium by Stropharia rugosoannulata 2# were determined using the orthogonal matrix method. The optimal defined medium (per liter) was 60.0 g sucrose, 6.0 g tryptone, 5 mM KH2PO4, and initial pH 7.0 at 28°C. In the optimal culture medium, the maximum EPS production was 9.967 g/L in shake-flask culture. One fraction of EPS was purified from the culture filtrates by size exclusion chromatography (SEC), and the molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The weight-average molar masses and the polydispersity ratio of the EPS fraction were determined to be 5.305 × 103 g/mol and 2.014, respectively. FTIR spectroscopy was used for obtaining vibrational spectra of the purified EPS fraction. The obvious characteristic absorption at 884.3 cm-1 revealed the existence of ß configuration. Furthermore, the experiments in vitro indicated that S. rugosoannulata 2# EPS exhibit high antitumor and antioxidative effects.

Evaluation of histone deacetylase inhibitors as therapeutics for neurodegenerative diseases.

Various neurodegenerative diseases are associated with aberrant gene expression. We recently identified a novel class of pimelic o-aminobenzamide histone deacetylase (HDAC) inhibitors that show promise as therapeutics in the neurodegenerative diseases Friedreich's ataxia (FRDA) and Huntington's disease (HD). Here, we describe the various techniques used in our laboratories to dissect mechanisms of gene silencing in FRDA and HD, and to test our HDAC inhibitors for their ability to reverse changes in gene expression in cellular models.