Structure and biological activities of polysaccharide purified from Senegrain seed

Characteristic analysis and fermentation optimization of a novel Aureobasidium pullulans RM1603 with high pullulan yield

A high-yielding microbial polysaccharide-producing strain, named RM1603, was isolated from rhizosphere soil and identified by morphological and phylogenetic analysis. The extracellular polysaccharides (EPS) were identified by thin-layer chromatography and infrared spectroscopy. The fermentation conditions were optimized by single factor experiments in shake flasks and a 5-L fermentor. The results of morphological and phylogenetic tree analysis showed that RM1603 was a strain of Aureobasidium pullulans. Its microbial polysaccharide was identified as pullulan, and the EPS production capacity reached 33.07 ± 1.03 g L-1 in shake flasks. The fermentation conditions were optimized in a 5-L fermentor, and were found to encompass an initial pH of 6.5, aeration rate of 2 vvm, rotor speed of 600 rpm, and inoculum size of 2 %. Under these conditions, the pullulan yield of RM1603 reached 62.52 ± 0.24 g L-1. Thus, this study contributes RM1603 as a new isolation with high-yielding pullulan and potential application value in biotechnology.

Modification of Welan gum with poly(2-oxazoline) to obtain thermoviscosifying polymer for enhanced oil recovery

Thermoviscosifying polymers refer to a category of smart materials that exhibit a responsive behavior to environmental stimuli, specifically demonstrating a natural rise in viscosity of solutions as the temperature increases. The temperature-dependent behavior exhibited by thermally viscous polymers renders them potentially advantageous in the context of Enhanced Oil Recovery (EOR). There exists a dearth of research pertaining to the application of thermoviscosifying polymer for better recovery in reservoirs characterized by high temperatures and high salt content. In order to tackle the mentioned concerns, this study examined the utilization of welan gum modified with poly(2-oxazoline) as thermally responsive chain segments to enhance viscosity. The objective was to evaluate the ability to enhance viscosity under thermal conditions and to assess their effectiveness in displacement of reservoir oil in high temperature and high salt environments. This study aimed to establish a theoretical framework for understanding the correlation between the molecular structure and performance of novel thermally viscous polymers. Additionally, it sought to offer practical insights into designing the molecular structure of thermally viscous polymers suitable for polymer flooding in high temperature and high salt environments. Furthermore, the study proposed the application of these new thermoviscosifying polymers for EOR.

Structural characterization and anti-oxidative activity for a glycopeptide from Ganoderma lucidum fruiting body

A water-soluble glycopeptide (named GL-PWQ3) with a molecular weight (Mw) of 2.40 × 104 g/mol was isolated from Ganoderma lucidum fruiting body by hot water extraction, membrane ultrafiltration, and gel column chromatography, which mainly consisted of glucose and galactose. Based on the methylation, FT-IR, 1D, and 2D NMR analysis, the polysaccharide portion of GL-PWQ3 was identified as a glucogalactan, which was comprised of unsubstituted (1,6-α-Galp, 1,6-β-Glcp, 1,4-β-Glcp) and monosubstituted (1,2,6-α-Galp and 1,3,6-β-Glcp) in the backbone and possible branches that at the O-3 position of 1,3-Glcp and T-Glcp, and the O-2 position of T-Fucp, T-Manp or T-Glcp. The chain conformational study by SEC-MALLS-RI and AFM revealed that GL-PWQ3 was identified as a highly branched polysaccharide with a polydispersity index of 1.25, and might have compact sphere structures caused by stacked multiple chains. Moreover, the GL-PWQ3 shows strong anti-oxidative activity in NRK-52E cells. This study provides a theoretical basis for further elucidating the structure-functionality relationships of GL-PWQ3 and its potential application as a natural antioxidant in pharmacotherapy as well as functional food additives.

Effect of monosaccharide composition and proportion on the bioactivity of polysaccharides: A review

Polysaccharides have been widely used in pharmaceutical and food industries due to their diverse bioactivity, high safety, and few or no side effects. However, inability to quickly produce, screen, and synthesize bioactive polysaccharides is the limiting factor for their development and application. Structural features determine and influence the bioactivity of polysaccharides. Among them, monosaccharide is the basic unit of polysaccharide, which not only affects electrification, functional group, and bioactivity of polysaccharide but also is one of the simplest polysaccharide indexes to be detected. At present, effects of monosaccharide composition and proportion on anti-inflammatory, antioxidant, antitumor, immunomodulatory, antibacterial, and prebiotic activities of polysaccharides are reviewed. Further problems need to be considered during regulation and analysis of monosaccharide composition and proportion of polysaccharides. Overall, present work will provide help and reference for production, development, and structure-function investigation of polysaccharides based on their monosaccharide.

Structural characterization of cell-wall polysaccharides purified from chayote (Sechium edule) fruit

Chayote (Sechium edule), an underutilized cucurbit vegetable crop, has gained attention as it exhibits health-promoting properties. However, the primary structure of chayote cell-wall polysaccharides has not been comprehensively studied. In this study, two cell-wall polysaccharides, CP-1 (41.1 KDa) and CP-2 (15.6 KDa), were extracted from chayote, and the structural analysis of CP-1 and CP-2 was carried out by monosaccharide composition analysis, Fourier transform infrared spectroscopy (FTIR), methylation analysis, and nuclear magnetic resonance spectroscopy (NMR). The results demonstrated that CP-1 was a galactan, and CP-2 was an anionic heteropolysaccharide composed of galacturonic acid, galactose, arabinose, rhamnose, glucose, glucuronic acid, mannose, and xylose in the molar ratio of 31.2:26.3:24.9:7.4:6.5:1.9:1.3:0.5. CP-2 has a backbone of → 4)-β-d-Galp-(1 → 3,6)-β-d-Galp-(1 → 3)-β-d-Galp-(1 → 4)-α-d-GalpA-(1→, with branches at O-6 of → 3,6)-β-d-Galp-(1→, consisting of α-l-Araf-(1 → 5)-α-l-Araf-(1 → 4)-β-d-Glcp-(1 →. Analysis of the structural and physicochemical properties confirmed the excellent application characteristics of CP-1 and CP-2. Hence, cell-wall polysaccharides of chayote could be used as new polysaccharides materials.

Antioxidant and DNA protecting activity of carboxymethylated polysaccharides from Cortex periplocae

In this study, polysaccharide from Cortex periplocae (CPP) was modified and three carboxymethylation modification polysaccharides (CPPCs) were obtained, and their physicochemical characteristics and in vitro biological activities were investigated. Based on the ultraviolet-visible (UV-Vis) scan, CPPs (CPP and CPPCs) did not contain nucleic acids or proteins. However, the Fourier transform infrared (FTIR) spectrum showed a new absorption peak around 1731 cm^-1. In addition, three absorption peaks near 1606, 1421, and 1326 cm^-1 were enhanced after carboxymethylation modification. Based on UV-Vis scan, the maximum absorption wavelength of Congo Red + CPPs exhibited a red-shift compared to Congo Red meant CPPs had a triple helix conformation. Scanning electron microscopy (SEM) indicated that CPPCs exhibited more fragments and non-uniform-sized filiform than CPP. Thermal analysis showed that CPPCs degraded between the temperature 240 °C-350 °C and CPP in the 270 °C-350 °C. In addition, the antioxidant and DNA protecting activities of CPPCs were significantly enhanced compared to CPP. Overall, this study demonstrated the potential applications of CPPs in food and pharmaceutical industries.

A novel Stauntonia leucantha fruits arabinogalactan: and structural characterization

Polysaccharides were the key ingredients of many herbal medicines, and were responsible for multiple pharmacological activities. In this study, a novel polysaccharide fraction, named SLP-2, was isolated from Stauntonia leucantha fruits, and purified by DEAE-52 and Sephadex G-100 column chromatography. Furthermore, SLP-2 was identified by congo red, methylation, partial acid hydrolysis and NMR. The results indicated that the backbone of SLP-2 was composed of →4)-β-D-Galp-(1 → 4)-β-D-Galp-(1→ substituted at C-6 with 1,5-linked arabinan. SLP-2 had good anti-oxidation ability in vitro. Surprisingly, we found that reduction of carboxyl groups and methylation of hydroxyl groups enhanced the ability to scavenge 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicals and inhibit lipid peroxidation, and weakened the activity to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and reduce ferric iron.

Phytochemical Profiling, Isolation, and Pharmacological Applications of Bioactive Compounds from Insects of the Family Blattidae Together with Related Drug Development

In traditional Chinese medicine (TCM), insects from the family Blattidae have a long history of application, and their related active compounds have excellent pharmacological properties, making them a prominent concern with significant potential for medicinal and healthcare purposes. However, the medicinal potential of the family Blattidae has not been fully exploited, and many problems must be resolved urgently. Therefore, a comprehensive review of its chemical composition, pharmacological activities, current research status, and existing problems is necessary. In order to make the review clearer and more systematic, all the contents were independently elaborated and summarized in a certain sequence. Each part started with introducing the current situation or a framework and then was illustrated with concrete examples. Several pertinent conclusions and outlooks were provided after discussing relevant key issues that emerged in each section. This review focuses on analyzing the current studies and utilization of medicinal insects in the family Blattidae, which is expected to provide meaningful and valuable relevant information for researchers, thereby promoting further exploration and development of lead compounds or bioactive fractions for new drugs from the insects.

Polysaccharide from Hemerocallis citrina Borani by subcritical water with different temperatures and investigation of its physicochemical properties and antioxidant activity

Hemerocallis citrina Borani as a low-cost vegetable, has various health benefits. However, the industry of H. citrina Borani is in the state of primary processing, with poor economic benefits. This study aimed to investigate the physicochemical properties, and the antioxidant activity of H. citrina Borani polysaccharide (HCBP) using subcritical water extraction (SWE) at different temperatures, to expand the value of H. citrina Borani. HCBP mainly composed of nine monosaccharides (glucose, galactose, rhamnose, fucose, mannose, arabinose, xylose, galacturonic acid, and glucuronic acid), among which the content of neutral sugar was higher and uronic acid was lower. HCBP contained glycosidic bond of β-configurations and trace quantities protein. The molecular weight of HCBP decreased with increasing temperature. Shear thinning occurred in HCBP with the increase of shear rate (0.01-1 s^-1), and the apparent viscosity of HCBP decreased at higher temperature (150-160°C) with the increase continuously of shear rate (1-10 s^-1), but almost remained constant at lower temperature (130-140°C). Scanning electron microscope showed that HCBP had rough surface, loose structure, obvious particle gap, and irregular shape. In addition, HCBP extracted at 160°C had strong FRAP activity, and HCBP extracted at 130 and 140°C had better ABTS radical scavenging activity. This study suggests that HCBP extracted by SWE could provide a cheap raw material as food thickening agent and natural antioxidants.

Polysaccharide from Hemerocallis citrina Borani by subcritical water: Bioactivity, purification, characterization, and anti-diabetic effects in T2DM rats

Hemerocallis citrina Borani (daylily) has various health benefits. However, the structural characterization and hypoglycemic effects of its polysaccharide remain unclear. Here, we first report for the first time, the effects of subcritical water extraction temperature on bioactivity of Hemerocallis citrina Borani polysaccharide (HCBP). HCBP extracted at 160 °C had better scavenging ability of free-radical and pancreatic lipase inhibition. This study aimed to investigate the structural characterization and anti-diabetic effects of aforementioned HCBP. HCBP was separated into three fractions using a DEAE-Sepharose Fast Flow. HCBP-1 was the major component with lower molecular weight, HCBP-2 was the least abundant component, HCBP-3 was the component with higher uronic acid and molecular weight. HCBP treatment significantly decreased the concentrations of fasting blood glucose, insulin, total cholesterol, triglyceride, and low density lipoprotein, as well as improved glucose intolerance and insulin resistance in type 2 diabetes mellitus (T2DM) rats. HCBP also protected the kidneys and pancreatic organs by histopathology and immunohistochemical analyses in T2DM rats. In addition, HCBP significantly increased the antioxidant enzymes activities and decreased the level of malonaldehyde to alleviated the oxidative stress injury. The results indicate HCBP extracted by subcritical water is promising functional food ingredients and could be used in T2DM treatment.

Antioxidant and Antibacterial Activities of a Purified Polysaccharide Extracted from Ceratonia siliqua L. and Its Involvement in the Enhancement Performance of Whipped Cream

The main objective discussed in this research was to determine the structural characteristics of carob kibble water-soluble polysaccharide (KWSP), extracted from Ceratonia siliqua L., and to assess its in vitro antioxidant activities, as well as its effect on whipped cream. The results obtained through 13C, 1H, and the hetero-nuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FT-IR) analysis indicated that KWSP had the characteristic bands of polysaccharides. Thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) suggested that KWSP is a hetero-polysaccharide composed of glucose and fructose, with an average molecular weight (Mw) amounting to 65 KDa. In addition, KWSP showed a good water holding capacity (WHC), a good oil holding capacity (OHC), and an emulsification stability, rated as 3.14 ± 0.05 g/g, 0.87 ± 0.02 g/g, and 71 ± 0.01%, respectively. The antioxidant activity of KWSP was investigated in vitro, demonstrating important DPPH and ABTS⋅+ radical scavenging activities and a good total antioxidant capacity. KWSP exhibited antibacterial activity against Listeria monocytogenes, Staphylococcus aureus, and Salmonella enterica. On the other hand, the incorporation of KWSP in whipped cream was investigated, to enhance its antioxidant capacity and consequently to extend its expiration date. Moreover, KWSP reduces the formation of conjugated dienes and trienes in cream fat.

Antioxidant activities, functional properties, and application of a novel Lepidium sativum polysaccharide in the formulation of cake

A novel heteropolysaccharide, named cress water soluble polysaccharide (CWSP), was purified from Lepidium sativum seeds. Antioxidant activities and functional properties were characterized thermally using thermal gravimetric analysis (TGA), and the differential scanning calorimeter (DSC) results of CWSP were evaluated. The total antioxidant capacity and the metal chelating activities of CWSP at 3 mg/ml were equivalent to 116.34 µg ascorbic acid and 62.57%, respectively. As for the CWSP that was used for the production of cakes, it was thermally stable, and it presented high water (WHC) and oil holding (OHC) capacities and good emulsion properties. The samples were prepared with different levels of CWSP (0.1. 0.3, and 0.5%) and analyzed during 15 days of storage at room temperature. The obtained results indicated that the addition of CWSP had a significant effect on the texture profile, leading to the increase in all parameters in terms of hardness, springiness, cohesiveness, adhesiveness, and chewiness. Moreover, the reformulation samples presented higher a* and lower L* and b* than the control sample. The sensory evaluation showed that the formulation of cake with 0.3% of CWSP was the most acceptable. Therefore, CWSP was shown to be a new alternative for improving the quality attributes, indicating potent antioxidant activities on the shelf life during the storage of bakery foods.

Purification, Structural Characterization, and Anti-Inflammatory Effects of a Novel Polysaccharide Isolated from Orostachys fimbriata

The present study elucidated the structural characteristics and anti-inflammatory activity of a novel polysaccharide isolated from Orostachys fimbriata, which is a traditional Chinese medicinal plant. O. fimbriata polysaccharide (OFP) was extracted and subsequently purified by chromatography using a DEAE cellulose-52 and Sephadex G-75 column. The molecular weight was determined as 6.2 kDa. HPGPC and monosaccharide composition analysis revealed a homogeneous polysaccharide containing only Glc. Chromatography and spectral analysis showed that the possible chemical structure consisted of →4)-α-Glcp-(1→ and a small quantity of →4,6)-β-Glcp-(1→ in the main chain and →6)-β-Glcp-(1→, α-Glcp-(1→, and β-Glcp-(1→ in the side chain. Morphological analysis using scanning electron microscopy (SEM) and atomic force microscopy (AFM) indicated that OFP had a multi-branched structure, and the sugar chain molecules of polysaccharide appeared aggregated. OFP was found to exhibit anti-inflammatory activity by reducing the secretion of inflammatory factors in RAW264.7 cells and by decreasing the extent of xylene-induced ear swelling in mice.

Structural Characterization and Antioxidant Activity of Exopolysaccharide from Soybean Whey Fermented by Lacticaseibacillus plantarum 70810

Soybean whey is a high-yield but low-utilization agricultural by-product in China. In this study, soybean whey was used as a substrate of fermentation by Lacticaseibacillus plantarum 70810 strains. An exopolysaccharide (LPEPS-1) was isolated from soybean whey fermentation by L. plantarum 70810 and purified by ion-exchange chromatography. Its preliminary structural characteristics and antioxidant activity were investigated. Results show that LPEPS-1 was composed of mannose, glucose, and galactose with molar ratios of 1.49:1.67:1.00. The chemical structure of LPEPS-1 consisted of →4)-α-D-Glcp-(1→, →3)-α-D-Galp-(1→ and →2)-α-D-Manp-(1→. Scanning electron microscopy (SEM) revealed that LPEPS-1 had a relatively rough surface. In addition, LPPES-1 exhibited strong scavenging activity against DPPH and superoxide radicals and chelating ability on ferrous ion. This study demonstrated that soybean whey was a feasible fermentation substrate for the production of polysaccharide from L. plantarum 70810 and that the polysaccharide could be used as a promising ingredient for health-beneficial functional foods.

Isolation, structural characterization and neuroprotective activity of exopolysaccharide from Paecilomyces cicada TJJ1213

Two exopolysaccharide fractions (EPS1 and EPS2) were obtained from Paecilomyces cicadae TJJ 1213, and their structures were elucidated. The EPS1 and EPS2 were mainly composed of mannose and galactose with molar ratios of 3.2: 1.0 and 2.7: 1.0, respectively. They possessed average molecular weights of 1.69 × 10⁶ and 8.06 × 10⁵ Da, respectively. Structural characterization indicated that the backbone of EPS1 was consisted of →4)-α-D-Manp (1→, →3,4)-α-D-Manp (1 → and →2,6)-α-D-Manp (1→, →6)-α-D-Galp (1→, →6)-β-D-Galp (1→, and side chain was consisted of α-D-Manp residue. The backbone of EPS2 was composed of →6)-β-D-Galp-(1→, →4)-α-D-Manp-(1→, →2,6)-α-D-Manp-(1 → and →6)-α-D-Galp-(1→, and the branching point was also consisted of α-D-Manp residue. In addition, EPS1 and EPS2 had potential in protective effects of PC12 cells against hydrogen peroxide induced oxidative stress by inhibiting the production of ROS, reducing LDH leakage and alleviating mitochondrial damage. These results indicated that EPS1 and EPS2 might serve as therapeutic agents for neuronal disorders.