•Acetyled and carboxymethylated derivatives of polysaccharide were prepared.•Their antioxidant and immunomodating activities were studied and compared.•The acetyled derivative with proper DS was ...superior to other derivatives.•The bioactivities are affected by the types of substitution groups and their DS.
A water-soluble polysaccharide extracted from Ganoderma atrum was chemically modified to obtain its acetyled and carboxymethylated derivatives. The results of chemical analysis, Fourier-transform infrared and 13C nuclear magnetic resonance spectroscopy showed that these modifications were successful, although the molecular weight of these derivatives decreased due to slight degradation during the reaction. The antioxidant and immunomodulating activities of these derivatives were then investigated to determine the structure–bioactivity relationship. Results showed that the acetyled derivative with appropriate degree of substitution and lower molecular weight exhibited stronger antioxidant abilities on scavenging DPPH radical, and inhibitory effects in β-carotene–linoleic acid systems compared with the native polysaccharide. In addition, it also enhanced the macrophage phagocytosis capacity and tumor necrosis factor-α secretion, whereas the carboxymethylated derivative was shown to be slightly less effective. These results indicated that the type of substitution group and their degree of substitution play a decisive role in the bioactivities of the derivatives.
Natural polysaccharides and their modified derivatives are crucial supplements to the prevention of inflammation. This study aimed to evaluate the effect of sulfated modification on the ...anti-inflammatory and anti-oxidative activities of Cyclocarya paliurus polysaccharides (CP). A sulfated CP, S-CP
was obtained using chlorosulfonic acid-pyridine method. The chemical components and FT-IR spectrum confirmed that sulfated group was synthesized to the polysaccharide chains successfully. S-CP
was found to inhibit nitric oxide production, phagocytic activity and the release of interleukin (IL)-6 and IL-1β in lipopolysaccharide-treated macrophage cells, RAW 264.7. S-CP
significantly decreased the secretion of IL-6 and TNF-α and the thymus and spleen indexes, and increased the production of IL-10 in lipopolysaccharide-treated mice. S-CP
could better protect the liver by inhibiting the activities of alanine aminotransferase and aspartate aminotransferase, and malondialdehyde level while increasing the superoxide dismutase activity and total anti-oxidative capacity. These results suggested that S-CP
may be an effective anti-inflammatory agent, and sulfated modification may be a reliable method for the development of food supplements.
The aim of the study was to determine the effects of salt concentration on traditional sauerkraut fermented spontaneously. Lactic acid bacteria (LAB), fungi and Escherichia coli (E. coli) in the ...brine were analyzed in the three kinds of sauerkraut. The contents of sugars (sucrose, glucose, fructose) and organic acids (lactic acid, acetic acid) in the brine and inside the cabbage were monitored by high-performance liquid chromatography (HPLC). In addition, the pH value was monitored in the brine. Results demonstrated that sucrose and glucose were consumed and fructose was accumulated gradually during fermentation. The whole fermentation process was dominated by LAB and a considerable accumulation of lactic acid was observed both in cabbage and brine at the end of fermentation. Salt concentration had a significant effect on sauerkraut fermentation at early stage. The LAB population and metabolic rate was reduced and the yield of lactic acid decreased with the increase of salt concentration. Suitable salt concentration can effectively inhibit the reproduction of fungi and E. coli. In comparison, high salt concentration delayed the maturation of sauerkraut and inhibited the metabolism of LAB.
•The variation of LAB, fungi and Escherichia coli in sauerkraut with different salt content were analyzed.•The content of sucrose, glucose, fructose, lactic acid and acetic acid in brine and cabbage were analyzed.•The fermentation characteristics of sauerkraut with different salt concentrations were revealed.
The viability of probiotic bacteria is always questionable when they exposed to the harsh environment and thus microencapsulation of probiotic bacteria is generally applied to enhance the viability ...during processing, storage, and also for the target delivery in gastrointestinal tract. Polysaccharide is one of the most widely used wall material in the area of probiotic microencapsulation. However, with the increasing demand and new application areas for probiotic microcapsules, traditionally used polysaccharides can barely satisfy such challenges. Therefore, seeking for new kinds of polysaccharides with preponderant properties that suitable for probiotic microencapsulation is now catching the interest of researchers and has important implication. This review focuses on the application of polysaccharides in the area of probiotic microencapsulation, including to classify the traditional polysaccharides according to their characteristic properties used especially for microencapsulation of probiotics, as well as to give a critical perspective on emerging polysaccharides applied as wall materials to encapsulate probiotic bacteria.
Traditional and emerging polysaccharides applied in microencapsulation of probiotic.
Exopolysaccharides (EPS) from lactic acid bacteria (LAB) have been reported to play vital parts in the modulation of cell-cycle and apoptosis in cancer cells. However, the mechanisms by which EPS ...regulate the proliferation and apoptosis of cancer cells remain incompletely understood. We thus used different cancer cells to evaluate the anticancer ability and to investigate the underlying molecular mechanism of EPS from Lactobacillus plantarum NCU116 (EPS116). Our studies showed that EPS116 inhibited the proliferation of cancer cells in a cell type manner, and remarkably repressed the growth and survival of CT26 through induction of apoptosis. Moreover, EPS116 increased the expression of pro-apoptotic genes, including Fas, Fasl and c-Jun, induced the phosphorylation of c-Jun in CT26 cells. Furthermore, TLR2 (Toll like receptor 2) was upregulated by EPS116, and the CT26 cells with TLR2 knockdown were found to be insensitive to EPS116, suggesting that the anti-cancer activity of EPS116 may be TLR2-dependent. Taken together, the suppressive efficacy of EPS116 on the proliferation of CT26 cells may be mediated via TLR2 and the activation of c-Jun dependent Fas/Fasl-mediated apoptotic pathway. Our study has, for the first time, shown that EPS from LAB induced c-Jun dependent Fas/Fasl-mediated apoptosis via TLR2 in CT26 cells.
Monosaccharide composition analysis is important to characterize the structure of complex carbohydrates. However, techniques for analyzing this in acidic polysaccharides are immature, due to ...incomplete hydrolysis. The aim of this paper is to provide an improved method for this using two-step acid hydrolysis combined with high-performance anion exchange chromatography. A weak acid was used to hydrolyze polysaccharides before hydrolyzing them with a strong acid to dissociate more monosaccharides. In the first step, samples were hydrolyzed using 0.09 M trifluoroacetic acid at 79 °C for 1.5 h to cleave some glycosidic bonds. After TFA removal, hydrolysis was continued at 100 °C for 2 h with 2 M sulfuric acid. The validity of this method was verified for acidic polysaccharides (including standard and three acidic polysaccharides from natural plants), and the total monosaccharides of all samples detected by the two-step acid hydrolysis method was significantly increased comparing to sulfuric acid hydrolysis alone. It suggests that this hydrolysis method could be applied to the monosaccharide composition analysis for acidic polysaccharides.
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•Two-step hydrolysis method was established to hydrolyze polysaccharides rich in uronic acid.•TFA was used to hydrolyze the polysaccharide in the first step, followed by sulfuric acid in the second step.•Response surface methodology was conducted to optimize hydrolysis conditions.
Chinese sauerkraut (also known as “PaoCai”), a kind of sound fermented vegetable product, is widely consumed in China. Changes of lactic acid bacteria flora throughout spontaneous fermentation of ...Chinese sauerkraut were analyzed in this study. Results have shown that Enterococcus faecalis, Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides subsp. mesenteroides, Lactobacillus plantarum, Lactobacillus casei and Lactobacillus zeae dominated the fermentation. E. faecalis and L. mesenteroides subsp. mesenteroides were present in the brine as soon as the vegetable was pickled while other four species were isolated successively during fermentation. E. faecalis and L. lactis subsp. lactis were mainly present in the early stage of fermentation and died at the later stage; L. mesenteroides subsp. mesenteroides did not die until the 5th day; L. zeae existed in the middle stage and disappeared at the 5.5th day. L. plantarum and L. casei dominated the final stage of fermentation. In summary, the fermentation process was initiated by L. mesenteroides subsp. mesenteroides, followed by E. faecalis, L. lactis, L. zeae and finally succeeded by L. plantarum and L. casei.
► We study the changes of LAB flora in spontaneous fermentation of Chinese sauerkraut. ► 6 species of LAB exist in the fermentation. ► Sequence of the appearance of LAB in fermentation has been determined.
There is growing interest in the antioxidants and antibacterial activity from natural substances. The purpose of the research was to gain and distinguish phenolic substances and organic acids in the
...Camellia oleifera
cake, and to study their antioxidant and antibacterial activities. The extraction and purification of them were achieved by solvent extraction and column separation, respectively. The conclusions displayed that purity of the phenolic substances was 94.1 ± 0.5% w/w and that of organic acid was 96.0 ± 0.3% w/w; Fifteen phenolic substances were certificated using HPLC–ESI–MS technology; oxalic, citric, acetic, malic, and succinic acids are discovered to be main organic acids. In addition, the phenolic substances and organic acids both have good antioxidant activity and obvious inhibition against six species of bacteria. These conclusions can be useful in the reuse of the waste of
Camellia oleifera
oil industry in the future.
In this work, resveratrol (Res) was incorporated into chitosan microspheres for controlled release and stabilisation. The microspheres were prepared by emulsion chemical cross-linking method, and ...vanillin was used as the novel cross-linker. The microspheres showed a smooth surface with irregular small particles and internal voids with a size distribution between 53 and 311
μm. Interpenetrating network cross-linking mechanisms might account for the Schiff base reaction between chitosan and vanillin. The encapsulation efficiency of Res within microspheres was up to 93.68%. Res contained within microspheres was protected from light and heat compared with the free Res. In addition, release behaviours were governed by two distinct stages and dependent on pH of release media. Diffusion, swelling and erosion mechanisms might coexist for the full controlled release and Higuchi was the most suitable model for the whole release procedure. Thus, controlled release and stabilization of Res were achieved through incorporation of Res into cross-linked chitosan microspheres by vanillin.
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