A new water-soluble polysaccharide from Echinops pungens Trautv roots. Part I. Isolation, purification, characterization and antioxidant activity

Liquid culture of Pleurotus nebrodensis mycelium with high yield and extraction and anti-fatigue activity of its polysaccharides

In this study, the liquid culture system of Pleurotus nebrodensis mycelium with high yield were established by using orthogonal experiments. Results indicated a 58.08 % increase in mycelium biomass and a 2.22 % increase in polysaccharide content after condition optimization. Experiments showed that the extracted polysaccharides have significant antioxidant and anti-exercise fatigue activities. They could effectively scavenge DPPH, ABTS, hydroxyl free radicals and superoxide anaion, prolong weight-loaded swimming time in mice, reduce levels of MDA, LD, and LDH in serum, enhance SOD activity, as well as increase hepatic and muscle glycogen reserves. The mechanism may be attributed to the activation of the Nrf2/Keap1 signaling pathway, inhibition of oxidative stress, and subsequent exerting anti-fatigue effects. The results in this work provides new avenue for easily accessible natural polysaccharide resources with a very convenient approach, which is beneficial for the development of anti-fatigue functional foods for public consumption.

Chemical structure and immunomodulatory activity of a polysaccharide from Saposhnikoviae Radix

A new polysaccharide, named SP40015A01, was obtained from Saposhnikoviae Radix by water extraction, isolation and purification. SP40015A01 (9.7 × 105 Da) is composed of Rhamnose (Rha), Galacturonic acid (GalA), Galactose (Gal), and Arabinose (Ara) with the proportion of 1.6:85.6:5.8:7.6. The backbone of SP40015A01 is composed of 3-α-GalAp, 2-α-GalAp, 2,3-β-GalAp and 2,3-β-Galp, and branched at C3 of 2,3-β-GalAp, C3 of 2,3-β-Galp. Zebrafish experiments were used to explore the immunomodulatory activity of SP40015A01. Results showed that SP40015A01 could significantly improve the neutrophils density of immunocompromised zebrafish and reduce the content of nitric oxide (NO) and interleukin-1β (IL-1β). This study demonstrated that SP40015A01 has significant immunomodulatory activity, which can improve the neutrophils density and reduce inflammatory factor content, suggesting SP40015A01 may be a potential immunomodulator in Saposhnikoviae Radix (SR) for treatment of hypoimmunity related disease. This study supplemented the research on the polysaccharide components in traditional Chinese medicine and provided a scientific explanation for the development and clinical applications of SR.

Effects of different selenium biofortification methods on Pleurotus eryngii polysaccharides: Structural characteristics, antioxidant activity and binding capacity in vitro

The effects of selenium biofortification methods involving sodium selenite and selenium yeast on the structural characteristics, antioxidant activity and binding capacity of Pleurotus eryngii polysaccharides were investigated. Sodium selenite Se-enriched Pleurotus eryngii polysaccharides (Se-SPEP), selenium yeast Se-enriched Pleurotus eryngii polysaccharides (Se-YPEP), and Pleurotus eryngii polysaccharides (PEP) had Se contents of 20.548 ± 1.561, 19.822 ± 0.613, and 0.052 ± 0.016 μg/g, respectively. Compared with PEP, Se-SPEP and Se-YPEP had lower molecular weight and contained the same monosaccharides in varying molar ratios. The results of FT-IR, PS, ZP, and SEM indicated significant alterations in structural characteristics following selenium biofortification. Se-PEPs exhibited superior activity against ABTS, DPPH, and ·OH radicals, as well as the higher binding capacity for Cd2+ and Cu2+ compared to natural polysaccharides. The binding capacity of the polysaccharides for Cd2+ and Cu2+ was higher at pH 6.8 compared to pH 2.0, while the opposite was observed for Pb2+. Furthermore, Se-PEPs exhibited a significantly higher binding capacity for Cd2+ and Cu2+ at both pH levels compared to natural polysaccharides (P < 0.05). Se-YPEP displayed higher antioxidant activity than Se-SPEP, with their binding capacities reversed. These data indicated that selenium biofortification methods have different positive impacts on the structure and activity of polysaccharides compared to natural polysaccharides, making Se-PEPs promising dietary supplements for safeguarding the body against the risks posed by food-derived heavy metals.

Isolation and purification of polysaccharides from Bupleurum marginatum Wall.ex DC and their anti-liver fibrosis activities

Bupleurum marginatum Wall.ex DC [Apiaceae] (BM)is widely grown in southwestern China, and the whole plant is used as Traditional Chinese Medicine (TCM). Polysaccharides are main natural products in lots of TCM and have been studied for their effects of reducing oxidative stress, anti-inflammation and immune regulation. Herein, we investigated the extraction techniques of Bupleurum marginatum Wall.ex DC polysaccharides (BMP), the identification of their key components, and their ability to inhibit liver fibrosis in both cellular and animal models. Component identification indicated that monosaccharides in BMP mainly consisted of glucose, galactose, mannose, rhamnose, arabinose, and xylose. In vivo analysis revealed that BMP provided significant protective effects on N-Nitroso dimethylamine (NDMA)-induced liver fibrosis rats through reducing hepatomegaly, reducing tissue inflammation, and reducing collagen deposition. BMP also improved the hepatobiliary system and liver metabolism in accord to reduce the serum levels of ALT, AST, ALP, r-GT, and TBIL. In addition, BMP could reduce the level of inflammation and fibrosis through inhibition of IL-1β and TGF-β1. Cellular studies showed that the BMP could provide therapeutic effects on lipopolysaccharide (LPS)-induced cellular fibrosis model, and could reduce the level of inflammation and fibrosis by decreasing the level of TGF-β1, IL-1β, and TNF-α. Our study demonstrated that BMP may provide a new therapy strategy of liver injury and liver fibrosis.

A new application of hydrocolloids from Echinops setifer (Shekartighal): Mayonnaise-type sauces

Due to the importance of the production of functional and nutraceutical foods with high added value, Shekartighal was used to develop ready-made functional mayonnaise-type sauces and evaluate their physicochemical, sensory, and antioxidant properties over 60 days of storage. Shekartighal had, on average, 76.85% carbohydrate, 9.24% protein, 4.91% fat, 1.74% ash, 7.26% moisture, 20.38 mgGAE/g total phenol content, 14.31 μM ferrous sulphate/g, and 145.12 μg/mL antioxidant activity. The results indicated that Shekartighal had high water absorption capacity (408.01%) and emulsion stability (91.83%). Following the textural and sensorial study, the product that stood out as the best performer was the sauce containing 3% Shekartighal. Consequently, this product was selected for further evaluation, where its physicochemical and antioxidant properties were assessed for a 60-day duration under refrigerated storage (4°C). The formulation with 3% Shekartighal presented significantly more phenolic content and antioxidant properties than the control. During the 60-day refrigerated storage (4°C) period, the physicochemical and antioxidant parameters of the enriched sauce remained stable. The addition of Shekartighal to the sauce significantly improved its nutritional quality, and the sauce enriched with 3% Shekartighal demonstrated the most favorable characteristics among the different concentrations tested. Overall, these findings suggest that Shekartighal could be utilized as a natural ingredient to create a functional sauce with notable antioxidant and nutritional properties.

Efficient production and skincare activity evaluation of schizophyllan, a β-glucan derived from Schizophyllum commune NTU-1

Schizophyllan (SPG), a β-glucan produced by the fungus Schizophyllum commune, possesses a β-(1 → 3)-linked backbone with single β-(1 → 6)-linked glucose side chains at approximately every third residue. In this study, we screened SPG-producing strains of S. commune from different provinces in China. A candidate strain (NTU-1) with a high SPG yield was chosen, and the fermentation conditions were optimized. The optimal carbon and nitrogen sources were sucrose (40 g/L) and yeast extract (20 g/L), respectively. The optimal conditions for pH and temperature were 5.0 and 28 °C, respectively. Inclusion of 0.2 mg/L of 2,4-Dichlorophenoxyacetic acid in the medium further increased the SPG concentration. In a 5-L bioreactor, the fermentation cycle was reduced from the initial seven days to five days, and the concentration of SPG obtained was 21.3 g/L, which is the highest reported to date. In addition, we evaluated the bioactivity of the SPG prepared using strain NTU-1. The results showed that SPG had certain characteristics of anti-oxidation, anti-photoaging, and inhibition of melanin production, making it a promising reagent for skin care.

Structure characterization and immunomodulatory activity of a polysaccharide from Saposhnikoviae Radix

A new polysaccharide, named SP800201 with Mw of 2.17 × 10⁵ g/mol, was isolated from Saposhnikoviae Radix. The monosaccharide composition of SP800201 mainly contained Gal, GalA, Ara, and Rha. SP800201 has a core structure containing GalA as the backbone and side chains consisting of GalA, Gal, Ara and Rha. Cell and zebrafish experiments were used to explore the immunomodulatory activity of SP800201. Results of vitro RAW264.7 cell experiments showed that SP800201 could significantly improve the proliferation and phagocytosis of macrophages, and promote the release of NO, TNF-α, IL-1β, and IL-6. Results of vivo experiments in immunocompromised zebrafish showed that SP800201 could also significantly increase the density of immune cells, the number of macrophages, and reduce NO, TNF-α, IL-1β, and IL-6. The above results showed that the Saposhnikoviae Radix polysaccharide has certain immunomodulatory activity.

Preparation, characterization and bioactivities of selenized polysaccharides from Lonicera caerulea L. fruits

Native polysaccharide was obtained from Lonicera caerulea L. fruits (PLP). Two selenized polysaccharides (PSLP-1 and PSLP-2) were synthesized by the microwave-assisted HNO₃-Na₂SeO₃ method, where the selenium (Se) contents were 228 ± 24 and 353 ± 36 μg/g, respectively. The molecular weights of PLP, PSLP-1, and PSLP-2 were 5.9 × 10⁴, 5.6 × 10⁴, and 5.1 × 10⁴ kDa, respectively. PSLP-1 and PSLP-2 contained the same type of monosaccharides as PLP but with different molar ratios. The main chain structure of the native polysaccharide was not changed after selenization. PLP, PSLP-1, and PSLP-2 contained the same six types of glycosidic bonds. Bioactivity assays revealed that the two selenized polysaccharides possessed better antioxidant activities than PLP, but their bile acid-binding abilities and inhibitory activities on acetylcholinesterase (AChE) had weakened. In summary, PLP, PSLP-1, and PSLP-2 may be promising Se supplements in functional foods and inhibitors for the treatment of AChE.

Structure characterization and antioxidant activity analysis of polysaccharides from Lanzhou Lily

Lanzhou Lily (Lilium davidii var. unicolor) is a traditional medicinal plant and popular edible vegetable bulb in China. In this study, the polysaccharides of Lanzhou Lily (LLPs) were extracted by polyethylene glycol-based ultrasonic-assisted enzymatic extraction method (PEG-UAEE). The optimum process conditions were obtained by single-factor experiments and response surface methodology (RSM). Then, the preliminarily structure of LLPs was characterized by HPLC, FT-IR, and SEM, and its antioxidant activities were evaluated. The results showed that LLPs yield reached 14.75% under the optimized conditions: E/S ratio 1,400 U/g; pH 5.0, ultrasonic time 30 min; and ultrasonic temperature 50 °C. The LLPs has pyranoid ring, uronic acid, and the characteristic absorption peaks of -OH, C = O, and C-H. The results of scanning electron microscope indicated that the LLPs had irregular distribution, dispersed structure, and many holes. The HPLC analysis showed that the LLPs were heteropolysaccharide containing galactose (6.36%), glucose (76.03%), rhamnose (2.02%), and arabinose (7.09%). Moreover, the LLPs showed obvious antioxidant effect in vitro.

Selenium-containing polysaccharides isolated from Rosa laevigata Michx fruits exhibit excellent anti-oxidant and neuroprotective activity in vitro

Selenium-containing polysaccharides have potential as an organic selenium dietary supplement, owing to their low toxicity, few side effects, and easy absorption attributes. In this study, we isolated two novel homogeneous selenium-containing polysaccharides from Rosa laevigata Michx fruits (Se-RLFPs). Results from primary structural analysis revealed that Se-RLFPs were α - pyranose, and were both composed of rhamnose, xylose, glucose with an average molecular weight of 24 and 16 KDa, respectively. Selenium contents in Se-RLFP-I and Se-RLFP-II were 16.49 μg/g and 21.61 μg/g, respectively. Results from analysis of antioxidant and neuroprotective activity of the polysaccharides revealed that Se-RLFPs had a radical scavenging effect. Specifically, they effectively protected SH-SY5Y cells from H₂O₂-induced damage by enhancing antioxidant enzyme activities (SOD), total antioxidant capacity (T-AOC) and suppressing malondialdehyde (MDA) levels. Western blots showed that the underlying mechanisms of action may be related to the Nrf2/HO-1 signaling pathway. Taken together, these results suggested that Se-RLFPs have potential as a pharmaceutical agent for treatment of neurodegenerative diseases (NDDs) or as a selenium-complementary ingredient in functional foods.

Structural characterization and biological evaluation of a new O-acetyl-1,4-linked-β-d-mannan possessed potential application in hydrophilic polymer materials from Dendrobium devonianum

To explore the active polysaccharides from Dendrobium devonianum, a novel O-acetylmannan (DDP-1) with molecular weight of 117 kDa was isolated from D. devonianum. The chemical and instrumental analysis indicated that the DDP-1 was a homopolysaccharide containing a backbone chain composed of →4)-β-d-Manp-(1 → (71.4%) residue with internal →4)-2-O-acetyl-β-d-Manp-(1 → (14.2%), →4)-3-O-acetyl-β-d-Manp-(1 → (7.1%), and non-reducing end β-d-Manp-(1 → (7.3%) residues. Anticancer assay in vitro revealed that DDP-1 had anticancer activity against the growth of HepG2 and MCF-7 cancer cells. Moreover, cytokine secretion assays also presented that DDP-1 can promote cytokine production of TNF-α and IL-6 in THP-1 macrophage stimulated by PMA. Finally, the effects of isolation and purification on the microstructure of DDP-1 was studied by scanning electron microscope. The morphological features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials.

Structural characterization of a water-soluble polysaccharide from Angelica dahurica and its antitumor activity in H22 tumor-bearing mice

A novel Angelica dahurica polysaccharide (ADP) with Mw of 6.09 × 10³ Da was isolated. The contents of total sugar and uronic acid in ADP were 91.04% and 12.69%. The structure characteristics indicated that ADP was an acidic polysaccharide consisting of rhamnose, arabinose, galactose, glucose, mannose, glucuronic acid and galacturonic acid (0.09: 0.61: 1.88: 1: 0.14: 0.63: 0.03). Moreover, there were →3)-Manp-(1→, →4, 6)-Galp-(1→, →4)-Galp-(1→, →3)-Glcp-(1→, →5)-Araf-(1→, →2)-Galp-(1→ in ADP with relative molar ratios of 0.32:0.57:0.29:0.95:0.71:0.26. In vivo experiments suggested that ADP significantly inhibited the tumor growth of mice, increased the activities of spleen lymphocytes and natural killer (NK) cells, improved the cytokine level (IL-2 and TNF-α) and the proportions of lymphocyte subsets in the peripheral blood. The tumor cell progression was arrested in the G₁ phase, and the apoptosis rate of tumor cells were 7.54% and 19.32% at the dose of 100 and 200 mg/kg, which was consistent with the results of pathological observation. In summary, the study might provide a theoretical basis for the application on functional foods containing Angelica dahurica polysaccharides.

Structure and chain conformation of bioactive β-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 β-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 → 3), (1 → 4), (1 → 6)-linked β-d-glucose residues in the backbone, with two single β-D-Glcp attached at O-6 of β-(1 → 3) and β-(1 → 4)-linked residues separately as side chains. The repeat unit of GLSB50A-III-1 was deduced as follows.

Isolation and structure characterization of glucuronoxylans from Dolichos lablab L. hull

Polysaccharides were extracted by hot water and alkali in sequence from Dolichos lablab L. hull, and further purified by ion-exchange and gel columns. Hot water extracted D. lablab hull polysaccharide (DLHP) was rich in glucuronoxylan and pectin, and alkali extracted polysaccharide (DLHAP) mostly embraced glucuronoxylan. The structures of purified glucuronoxylans from DLHP and DLHAP were mainly analyzed by HPAEC-PAD, methylation combined with GC-MS, NMR and SEC-MALLS. DLHP-1 was identified as acetylated glucuronoxylan containing →4)-β-Xylp-(1→ backbone with substitution at O-2 site by α-GlcpA/4-O-methyl-α-GlcpA. The molar ratio of β-Xylp to α-GlcpA was 6.9:1, and acetylation was mainly at O-3 site of β-Xylp with acetylation degree of 21.5%. DLHP-1 and DLHP-2 had similar physicochemical properties, except for molecular weight (M_w). DLHAP-1 was the non-methylated glucuronoxylan almost without acetylation, and it had the molar ratio of β-Xylp to α-GlcpA of 5.6:1. Besides, DLHP-1 (M_w of 20.0 × 10³ g mol^-1) adopted semi-flexible chain, while DLHAP-1 (M_w of 15.4 × 10³ g mol^-1) showed flexible chain. These results provided a structural basis for study on polysaccharides from D. lablab hull, which was benefit for understanding biological activities and developing functional food or pharmaceuticals of D. lablab.

Isolation, structure characteristics and antioxidant activity of two water-soluble polysaccharides from Lenzites betulina

BACKGROUND

Fungal polysaccharides belong to a very important class of biological macromolecules in nature, and have complex monosaccharide composition and structure. These studies on structure and biological activity of fungal polysaccharides have become one of the research hotspots of scholars at home and abroad.

RESULTS

This study was performed in order to understand the structural characteristics and antioxidant activity of polysaccharides from Lenzites betulina (LBPs). The LBPs were deproteinized using sevag method, and further purified by DEAE cellulose-52 column and Sephadex G-100 column chromatographies, then the two refined polysaccharides were obtained and named LBPs-5 and LBPs-6. Fourier transform infrared spectrometry (FT-IR) showed that LBPs-5 and LBPs-6 are typical β-pyranose with characteristic peaks of polysaccharides. The molecular weight of the two water-soluble polysaccharides were estimated to be 3.235 × 10³ Da and 6.196 × 10³ Da by HPGPC, respectively. HPLC with PMP derivatization analysis indicated that the monosaccharide compositions of LBPs-5 were mannose, glucuronic acid, glucose, and galactose in a molar ratio of 0.05:0.15:0.76:0.04. The monosaccharide compositions of LBPs-6 were mannose, glucuronic acid, and glucose, in a molar ratio of 0.04:0.17:0.79. Furthermore, the two water-soluble polysaccharides demonstrated strong scavenging effects on DPPH·, ABTS·⁺, ·OH and weak total reducing power, especially LBPs-6 was significantly stronger in scavenging rate than that of LBPs-5.

CONCLUSIONS

The outcome of the study indicated that LBPs had good potential as medicine and food.

Arabinogalactan in banana: Chemical characterization and pharmaceutical effects

It is generally recognized that banana has diverse health benefits. However, most of the molecules responsible for the health benefits remain unknown. In this work, an important polysaccharide was extracted from banana and purified. The molecular weight was determined to be 526.2 kDa. It was identified by chemical and spectroscopic methods as arabinogalactan with β-D-(1→6)-galactan as backbone. This arabinogalactan was comprised of three monosaccharides, including Ara, Gal and GlcA with a relatively molar ratio of 5.8: 5.9: 1.0. The side chains were identified to be α-L-Araf-(1→, β-D-GlcpA-(1→, α-L-Araf-(1→5)-α-L-Araf-(1→ and α-D-Galp-(1→3)-α-L-Araf-(1→. They were linked to β-D-(1→6)-galactan at O-3, respectively. The putative structure was drawn as below. This arabinogalactan could induce NO production. It could also inhibit ROS production with a dose-dependent behaviour.