Research on the application of Thelephora ganbajun exopolysaccharides in antioxidant, anti-inflammatory and spot-fading cosmetics.

Thelephora ganbajun exopolysaccharides (TGEP) with a "coral-like" branched chain structure (main chain diameter âˆ¼ 80 nm) were prepared by liquid fermentation and fractionated by ion-exchange chromatography. The main fraction (TGEP-2) with the highest in vitro antioxidant capacity was composed of Glc, Man, Gal, GalA, GlcA, Ara, Rha, GlcN, Fuc and Rib in a molar ratio of 465.43:420.43:219.14:188.43:37:35.14:31.43:19.43:11.14:1, with a molecular weight of 1.879 × 104 Da. The sequence of monosaccharide residue release revealed that Gal, Glc and Ara residues were more distributed in the side-branch chains and at their ends, whereas Man and GalA residues were more distributed in the main chains. TGEP-2 contained linear residues (mainly →4)-Glcp-(1 â†’ and →4)-Manp-(1→), branch residues (→3,6)-Glcp-(1→, →4,6)-Glcp-(1 â†’ and →3,6)-Galp-(1→) and terminal residues (Galp-(1→, Manp-(1 â†’ and Glcp-(1→). TGEP-2 consisted of α- and ß-glycosidically linked pyranosides, with a triple helical conformation and many long branches. Zebrafish oxidative stress and inflammation models found that TGEP-2 had antioxidant and anti-inflammatory activities. The zebrafish skin black spot assay showed that TGEP-2 inhibited melanin formation. Therefore, extracellular polysaccharides of T. ganbajun have strong application potential in anti-oxidant, anti-inflammatory and skin spot-fading functions cosmetics.

Preparation and structure-activity relationship of highly active black garlic polysaccharides.

The aim of this study was to establish a method to improve the biological activity of polysaccharides. Three acid-treated polysaccharides (BGPS-2, BGPS-3 and BGPS-4) were obtained by treating black garlic polysaccharides (BGPS-1) with sulfuric acid at different intensities. The structure was characterized using the sulfuric acid-carbazole assay, IC, HPSEC-MALLS and FT-IR. The biological functions were evaluated using antioxidant and melanin biosynthesis inhibition assays. Compared with BGPS-1, the molecular weight of acid-treated polysaccharides significantly decreased, and the uronic acid content significantly increased. Antioxidant capacity negatively correlated with molecular weight, whereas melanin inhibition activity positively correlated with uronic acid content. BGPS-4 had the highest antioxidant capacity and the lowest molecular weight (1.25 × 103 Da), 79.41 % lower than that of BGPS-1. BGPS-3 was the strongest inhibitor of melanin formation and had the highest uronic acid content (50.73 %), 238.2 % higher than that of BGPS-1. Molecular weight and uronic acid content were the main structural characteristics that affected the antioxidant and melanin biosynthesis inhibition activities, respectively. BGPS-1, BGPS-2, BGPS-3, and BGPS-4 all had ß-linked pyranose, multi-branched, and non-triple helical spiral structures. Therefore, the acid hydrolysis method markedly modified the structural characteristics of black garlic polysaccharides, and increased their antioxidant capacity and melanin biosynthesis inhibition activity.

A glucose biosensor based on glucose oxidase fused to a carbohydrate binding module family 2 tag that specifically binds to the cellulose-modified electrode.

The method of immobilization of glucose oxidase (GOD) on electrodes is especially important for the fabrication and performance of glucose biosensors. In this study, a carbohydrate binding module family 2 (CBM2) was successfully fused to the C terminal of GOD with a natural linker (NL) in endo-ß-xylanase by genetic recombination, and a fusion GOD (GOD-NL-CBM2) was obtained. The CBM2 was used as an affinity adsorption tag for immobilization of the GOD-NL-CBM2 on a cellulose modified electrode. The specific activity of GOD-NL-CBM2 was comparable to that of the wild type GOD. In addition, the CBM2 tag of fusion GOD almost maintained its highest binding capacity under optimal catalytic conditions (pH 5.0, 50 °C). The morphology and composition analysis of the cellulose film reacted with and without GOD or GOD-NL-CBM2 confirmed the immobilization of GOD-NL-CBM2. The electrochemical properties of the GOD-NL-CBM2/cellulose film bioelectrode, with a characteristic peak of H2O2 at +0.6 V in the presence of glucose, revealed the capability of the immobilized GOD-NL-CBM2 to efficiently catalyze glucose and produce H2O2. Additionally, the current signal response of the biosensor to glucose was linear in the concentration range from 1.25 to 40 mM (r2 ≥ 0.99). The sensitivity and detection limit of the GOD-NL-CBM2/cellulose film bioelectrode were 466.7 µA mol-1 L cm-2 and 0.475 mM (S/N = 3), respectively. Moreover, the glucose biosensor exhibited a rapid current change (< 5 s), high reproducibility (Relative standard deviation, RSD < 5%), substrate selectivity and stability, and retained about 80 % of the original current response after 2 months. The affinity adsorption-based immobilization strategy for GOD provides a promising approach to develop a high performance glucose biosensor.

Orientated Immobilization of FAD-Dependent Glucose Dehydrogenase on Electrode by Carbohydrate-Binding Module Fusion for Efficient Glucose Assay.

The discovery or engineering of fungus-derived FAD-dependent glucose 1-dehydrogenase (FAD-GDH) is especially important in the fabrication and performance of glucose biosensors. In this study, a novel FAD-GDH gene, phylogenetically distantly with other FAD-GDHs from Aspergillus species, was identified. Additionally, the wild-type GDH enzyme, and its fusion enzyme (GDH-NL-CBM2) with a carbohydrate binding module family 2 (CBM2) tag attached by a natural linker (NL), were successfully heterogeneously expressed. In addition, while the GDH was randomly immobilized on the electrode by conventional methods, the GDH-NL-CBM2 was orientationally immobilized on the nanocellulose-modified electrode by the CBM2 affinity adsorption tag through a simple one-step approach. A comparison of the performance of the two electrodes demonstrated that both electrodes responded linearly to glucose in the range of 0.12 to 40.7 mM with a coefficient of determination R2 > 0.999, but the sensitivity of immobilized GDH-NL-CBM2 (2.1362 × 10-2 A/(M*cm2)) was about 1-fold higher than that of GDH (1.2067 × 10-2 A/(M*cm2)). Moreover, a lower detection limit (51 µM), better reproducibility (<5%) and stability, and shorter response time (≈18 s) and activation time were observed for the GDH-NL-CBM2-modified electrode. This facile and easy immobilization approach used in the preparation of a GDH biosensor may open up new avenues in the development of high-performance amperometric biosensors.

Increased antioxidant activity and improved structural characterization of sulfuric acid-treated stepwise degraded polysaccharides from Pholiota nameko PN-01.

The aim of this study was to investigate sulfuric acid degradation of the Pholiota nameko polysaccharide (AIPS-1). Three stepwise degraded polysaccharides (AIPS-2, AIPS-3, and AIPS-4) were obtained by sequentially increasing the strength of sulfuric acid treatment. Structural characterization showed that sulfuric acid treatment significantly decreased molecular weight, increased the content of uronic acid and changed the molar ratio of monosaccharide composition, while the major functional groups and the triple helical conformation of polysaccharides did not change significantly. In vitro experiments proved that the antioxidation ability of the stepwise degraded polysaccharides gradually increased (AIPS-1 < AIPS-2 < AIPS-3 < AIPS-4). An oxidative stress zebrafish model was established, which demonstrated that the ability of AIPS-3 and AIPS-4 to scavenge free radicals in zebrafish was significantly improved compared to AIPS-1. In conclusion, sulfuric acid treatment is an effective method for improving the antioxidant activity of polysaccharides, and increased antioxidant activity was closely related to the changes in their structural characteristics.

Distribution of Zinc in Mycelial Cells and Antioxidant and Anti-Inflammatory Activities of Mycelia Zinc Polysaccharides from Thelephora ganbajun TG-01.

This study demonstrates that Thelephora ganbajun had a strong ability to absorb zinc, and zinc can be compartmentally stored in the small vesicles and mainly accumulated in the form of zinc-enriched polysaccharides (zinc content was 25.0 ± 1.27 mg/g). Mycelia zinc polysaccharides (MZPS) and its fractions were isolated. The main fraction (MZPS-2) with the highest antioxidant activity in vitro was composed of mannose : galacturonic acid : glucose : galactose in a molar ratio of 61.19 : 1 : 39.67 : 48.67, with a weight-averaged molecular weight of 5.118 × 105 Da. MZPS-2 had both α-pyranose and ß-pyranose configuration and had a triple helical conformation. By establishing zebrafish models, we found that MZPS-2 can significantly scavenge free radicals, reduce the generation of reactive oxygen species caused by inflammation, and inhibit the recruitment of neutrophils toward the injury site. Therefore, MZPS-2 exhibited antioxidant and anti-inflammatory effects and can be used as a zinc supplement with specific biological activities to alleviate zinc deficiency complications, such as chronic oxidative stress or inflammation.

Colorimetric and ratiometric fluorescent response for anthrax bio-indicator: A combination of rare earth MOF and rhodamine-derived dye.

Bacillus anthracis spores have a unique biomarker of calcium dipicolinate (CaDPA). In this work, we reported a composite nanostructure for the optical sensing of DPA, with Eu (III)-doped metal-organic framework (MOF) as supporting lattice, a rhodamine-derived dye as sensing probe, respectively. By means of XRD, IR, TGA and photophysical analysis, this composite structure was carefully discussed. It was found that rhodamine absorption and emission were enhanced by DPA, while Eu emission was quenched by DPA. As a consequence, two sensing skills were observed from this composite structure, which are colorimetric sensing based on absorption spectra and ratiometric fluorescent sensing based on emission spectra. Linear sensing response was observed for both sensing channels with a warning signal at DPA concentration higher than 140 µM. Good selectivity was confirmed with a low LOD value of 0.52 µM. The sensing mechanism was revealed as the combination of emission turn-on effect triggered by DPA-released protons and emission turn-off effect originated from electron-transfer from EuBTC to DPA. This composite structure showed its advantage of naked eye detection and two sensing skills with linear response.