“…These outcomes demonstrated that EPS had a detectable effect on the scavenging of free radicals, particularly at high concentration. Such results are in accordance with those found by many workers [3], [54], [55], [56].Fig. 4Free radical scavenging effects of EPS from Streptomyces carpaticus (strain No.…”
Twenty streptomycete strains were isolated from marine sediment samples collected from Nabq area, Sharm El-Sheikh, Red Sea Coast, Egypt. Four of them produce exopolysaccharides (EPS) showing marked in vitro antitumor activities. Morphological and cultural characteristics of the most significant strain (No. 3) were shown. Moreover, the sequence of this strain showed similarity with Streptomyces carpaticus. The results reveal that EPS produced by Streptomyces carpaticus No. 3 had high cytotoxicity reaching 51.7% and 59.1% against human tumor cells of breast and colon lines respectively. A chemical analysis of EPS indicated that the composing monosaccharides were galactouronic acid, glucose, xylose, galactose, mannose, and fructose with relative ratio of 3:1:1:2:2:1 respectively, with an average molecular weight (Mw) 1.180 × 105 g/mol and of a number average molecular weight (Mn) 1.052 × 105 g/mol. Also the EPS contained uronic acid (0.5072%) and monosaccharide sulphates (21.753%).
“…These outcomes demonstrated that EPS had a detectable effect on the scavenging of free radicals, particularly at high concentration. Such results are in accordance with those found by many workers [3], [54], [55], [56].Fig. 4Free radical scavenging effects of EPS from Streptomyces carpaticus (strain No.…”
Twenty streptomycete strains were isolated from marine sediment samples collected from Nabq area, Sharm El-Sheikh, Red Sea Coast, Egypt. Four of them produce exopolysaccharides (EPS) showing marked in vitro antitumor activities. Morphological and cultural characteristics of the most significant strain (No. 3) were shown. Moreover, the sequence of this strain showed similarity with Streptomyces carpaticus. The results reveal that EPS produced by Streptomyces carpaticus No. 3 had high cytotoxicity reaching 51.7% and 59.1% against human tumor cells of breast and colon lines respectively. A chemical analysis of EPS indicated that the composing monosaccharides were galactouronic acid, glucose, xylose, galactose, mannose, and fructose with relative ratio of 3:1:1:2:2:1 respectively, with an average molecular weight (Mw) 1.180 × 105 g/mol and of a number average molecular weight (Mn) 1.052 × 105 g/mol. Also the EPS contained uronic acid (0.5072%) and monosaccharide sulphates (21.753%).
“…It is a popular edible mushroom with a unique flavor and smooth taste. Polysaccharides from P. geesteranus have strong antioxidant [ 19 ], blood lipid lowering [ 20 ], and antitumor properties [ 21 ]. However, information about the Se-combining polysaccharide of P. geesteranus is scarce.…”
Selenium- (Se-) enriched polysaccharide SPMP-2a was extracted and purified from Pleurotus geesteranus. SPMP-2a is a white flocculent polysaccharide and soluble in water, with a molecular weight of 3.32 × 104 Da. Fourier transform infrared spectroscopy spectral analysis indicated that it belongs to an acid Se polysaccharide with α-D-glucopyranoside bond. The effects of Se polysaccharide SPMP-2a in P. geesteranus against hydrogen peroxide- (H2O2-) induced oxidative damage in human keratinocytes (HaCaT) cells were evaluated further. Reduced cell viability and elevated apoptotic rates in H2O2-treated HaCaT cells were proven by MTT and flow cytometry assays. Hoechst 33342 staining revealed chromatin condensations in the nuclei of HaCaT cells. However, with the addition of SPMP-2a, cell viability improved, nuclear condensation declined, and cell apoptotic rates dropped significantly. Ultrastructural observation consistently revealed that treatments with SPMP-2a reduced the number of swollen and vacuolar mitochondria in the H2O2-treated cells compared with the controls. Furthermore, SPMP-2a increased the superoxide dismutase (SOD) and catalase (CAT) activities and reduced reactive oxygen species (ROS) content. Western blot analysis showed that SPMP-2a treatment effectively increased B-cell lymphoma 2 (Bcl-2) protein expression. Therefore, SPMP-2a could improve cellular antioxidant enzyme activities, reduce ROS levels, and increase Bcl-2 protein expression levels, thereby reducing cell apoptosis and protecting HaCaT cells from H2O2-induced oxidative damage.
“…The β‐type pyranose has evident physiological activity. For example, the polysaccharide of the mycelium of Pleurotus geesteranus is β‐pyranose, which has remarkable liver protection activity 54 . The α‐type pyranose has evident immunity.…”
Section: Resultsmentioning
confidence: 99%
“…For example, the polysaccharide of the mycelium of Pleurotus geesteranus is ⊎-pyranose, which has remarkable liver protection activity. 54 The ⊍-type pyranose has evident immunity. The linkage of each glycosyl residue in polysaccharides has a supplementary effect on its biological activity.…”
BACKGROUND: A polysaccharide was purified in this study, which was acquired from the fermentation broth of Dendrobium officinale Kimura et Migo. We aimed to investigate the structural features and bioactivity of this polysaccharide.
RESULTS:The polysaccharide was purified and the main polysaccharide fraction (i.e., DOP-1) was obtained. High-performance gel permeation chromatography (HPGPC) revealed that the molecular weight of DOP-1 was 447.48 kDa. Galactose, glucose and mannose were found to be present in DOP-1 via monosaccharide composition analysis, at a ratio of 1:1.79:6.71. Methylation and nuclear magnetic resonance spectroscopic analysis indicated that the backbone of DOP-and its repeating units were also preliminarily established. In vitro tests proved that DOP-1 not only protects RAW264.7 macrophages from the cytotoxic effect induced by lipopolysaccharide (LPS), but also inhibits cytokines (i.e., interleukin-6 and tumour necrosis factor-⊍) induced by LPS. DOP-1 demonstrated good scavenging activity in vitro toward 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals, as well as good metal chelating activity. Therefore, DOP-1 has potential antioxidant applications.CONCLUSION: The structural characteristics of DOP-1 support its favourable biological activities and lay a strong foundation for further exploration of its structure-activity relationships and activity development, providing experimental data for the development and utilisation of fermentation broth of D. officinale.
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