ABSTRACT
ObjectiveTo establish the characteristic sugar spectrum of polysaccharides， oligosaccharides and monosaccharides of wild-simulated and transplanted Astragali Radix， and find out the difference of the sugar spectrum between the two， so as to provide a basis for quality evaluation of Astragali Radix. MethodThe relative molecular weight distribution of polysaccharides from 18 batches of wild-simulated Astragali Radix and 12 batches of transplanted Astragali Radix were characterized by high performance liquid chromatography-evaporative light scattering detection（HPLC-ELSD） to establish the characteristic chromatograms of two kinds of polysaccharides. The difference in the peak area ratio of APS-Ⅱ， a polysaccharide component with a relative molecular weight of 10 kDa， in two kinds of Astragali Radix was analyzed， and the critical value of peak area ratio of APS-Ⅱ was determined by receiver operating characteristic（ROC） curve. At the same time， APS-Ⅱ was partially acid-hydrolyzed by trifluoroacetic acid（TFA） to establish characteristic spectra of two kinds of oligosaccharides from Astragali Radix based on HPLC-ELSD， and the characteristics of differential oligosaccharides were found by principal component analysis（PCA） and orthogonal partial least squares-discriminant analysis（OPLS-DA）. Two kinds of APS-Ⅱ were completely acid-hydrolyzed by TFA and derivatized to establish characteristic spectra of two kinds of monosaccharides from Astragali Radix based on HPLC， PCA and OPLS-DA were performed on the peak area ratio of two kinds of monosaccharides to explore the differences in the composition of two kinds of APS-Ⅱ monosaccharides. ResultThe characteristic sugar spectrum of polysaccharides from Astragali Radix showed that the peak area ratio of APS-Ⅱ was the main difference， and the peak area of APS-Ⅱ of wild-simulated and transplanted Astragali Radix were 89.17%-97.17% and 80.14%-91.96%， respectively. The ROC curve determined the critical value of 92.28% for the difference of APS-Ⅱ peak area ratio of the two kinds of Astragali Radix. The multivariate analysis of APS-Ⅱ oligosaccharides revealed that the peak area ratio of oligosaccharides with polymerization degree≥10 was the main difference， which ranged from 11.835%-19.092% for wild-simulated products and 2.778%-7.017% for transplanted products. The results of monosaccharide characteristic sugar spectrum analysis showed that both Astragali Radix species consisted of six monosaccharides， and glucose and arabinose were the differential monosaccharide fractions. The peak area ratios of glucose and arabinose in wild-simulated products were 85%-93.9% and 2.7%-5.8%， respectively， while those of transplanted products were 74.3%-87.3% and 5.3%-10.7%， suggesting that the structures of the two polysaccharide fractions APS-Ⅱ of Astragali Radix may be different. ConclusionThe difference of sugar spectrum between two kinds of Astragali Radix may be related to the content and structure of APS-Ⅱ， and this study may provide a reference for the study of carbohydrates in Astragali Radix and the quality evaluation of medicinal materials.
ABSTRACT
The biofilms formed by pathogenic microorganisms seriously threaten human health and significantly enhance drug resistance, which urgently call for developing drugs specifically targeting on biofilms. Chitooligosaccharides extracted from shrimp and crab shells are natural alkaline oligosaccharides with excellent antibacterial effects. Nevertheless, their inhibition efficacy on biofilms still needs to be improved. Spirulina (SP) is a microalga with negatively charged surface, and its spiral structure facilitates colonization in the depth of the biofilm. Therefore, the complex of Spirulina and chitooligosaccharides may play a synergistic role in killing pathogens in the depth of biofilm. This research first screened chitooligosaccharides with significant bactericidal effects. Subsequently, Spirulina@Chitooligosaccharides (SP@COS complex was prepared by combining chitooligosaccharides with Spirulina through electrostatic adsorption. The binding of the complex was characterized by zeta potential, z-average size, and fluorescence labeling. Ultraviolet-visible spectroscopy (UV-Vis) showed the encapsulation efficiency and the drug loading efficiency reached up to 90% and 16%, respectively. The prepared SP@COS2 exhibited a profound synergistic inhibition effect on bacterial and fungal biofilms, which was mainly achieved by destroying the cell structure of the biofilm. These results demonstrate the potential of Spirulina-chitooligosaccharides complex as a biofilm inhibitor and provide a new idea for addressing the harm of pathogenic microorganisms.
Subject(s)
Humans , Spirulina , Anti-Bacterial Agents/chemistry , Chitosan/pharmacology , Biofilms , Chitin/pharmacologyABSTRACT
The inhibitory effect of NACOS on dyslipidemia and potential molecular mechanisms by in vitro and in vivo experiments were investigated. For in vitro study, four experimental groups were designed by using HepG2 cells, including the control group, palmitic acid (PA) treatment alone group, NACOS treatment alone group and NACOS + PA treatment group. For in vivo study, male C57BL/6 mice were divided into four groups (n=5) at random including the normal control group (NCD), high fat diet (HFD) group, NACOS treatment alone group, NACOS+HFD group, which were treated for 20 weeks. The used methods in this study were as follows: the observation of lipid droplet deposition in HepG2 cells by oil red O staining, the detection of mRNA levels of lipid metabolism-related regulators and inflammatory cytokine by RT-PCR method, the monitoring of MAPKs and PI3K/Akt pathway activation by Western blotting method. The in vitro study shows that, NACOS had no toxicity on the viability of HepG2 cells at 25-100 μg/mL and significantly reduced the deposition of lipid droplet. Also, based on both in vitro and in vivo investigation, NACOS evidently down-regulated the expression of lipid metabolism-related regulators (PGC1α, Cox5b, Mcad) and inflammatory cytokine (IL-1β) at mRNA level (P<0.05 or 0.01), and suppressed the activation of p38, ERK1/2 and Akt in HepG2 cells and lever tissues from HFD-fed mice (P<0.05 or 0.01). Based on the above, NACOS may inhibit the oxidation of liver mitochondrial fatty acid and the lipid biosynthesis, block the inflammatory responses and prevent the HepG2 cells and C57BL/6 mice from lipidemia.
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Objective To investigate the effects of oligochitosan on the humoral and cellular immunity in mice.Methods Divided the mice into four groups,test groups were given ip oligochitosan at doses of 60,120,240 mg?kg~(-1) for 14 days and the control group was given(0.9%) NS. The number of haemolytic empty spots,the level of serum hemolysin,the transform rate of T lymphocytes induced by ConA,delayed hypersensitivity were measured.Results Compared with the control group,indices including the number of haemolytic empty spots,the level of serum hemolysin,the transform rate of T lymphocytes induced by ConA,spleen ratio,ears swelling degree increased obviously in the dose of 120mg?kg~(-1) after two weeks of treatment.Conclusion Proper dose of oligochitosan can enhance the specific humoral and cellular immunity in mice.
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The bioactivity tests showed that the induce resistance of oligochitosan was close relation with its degree of polymerization (DP) and its degree of deacetylation (DDA), the oligochitosan with low DP and high DDA has high induce resistance. In this paper, we used HPLC method and TOF-MS method detecting the DP and DDA of oligochitosan.