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Chlorella contains a variety of polysaccharides with complex composition and structure, which are composed of various monosaccharides such as galactose, rhamnose, glucose, arabinose, mannose, xylose and glucuronic acid. The glycosidic linkages of polysaccharides are diverse, including α-1,6-glucose, β-1,3-galactose, α-1,6-galactose, α-1,3-rhamnose, α-1,2-rhamnose, α-1,5-arabinose, α-1,6-mannose and β-1,4-xylose. Some polysaccharides are modified by methylation, sulfation and acetylation. Meanwhile, many studies have shown that polysaccharides have multiple functions such as immunoregulatory, anti-inflammatory, antioxidant, anti-tumor, antibacterial and intestinal flora-regulatory effects. At present, monosaccharide composition analysis, methylation combined with gas chromatography-mass spectrometry (GC-MS) and two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy are mainly used for research on the structure of chlorella polysaccharides such as analysis of monosaccharide composition, glycosidic bond types, branch chain substitution positions and branch chain types. This review hopes to provide valuable information for the fine structural analysis and structure-activity relationship study of polysaccharides from Chlorella.

Objective: This study aimed to compare the compositions of peptides from Engraulis japonicus and Glycine max and their immunomodulatory effects on the intestinal mucosa in mice. Methods: The sequences of peptides from E. japonicus and G. max were analyzed by ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-MS/MS) combined with Peaks Online 1.7 software, and the differences in peptide composition were compared. The effects of the two peptides on the mucosal structure, immune factors, immunoglobulin (Ig) levels, and gene expression of factors associated with the Toll-like receptors (TLRs)/nuclear factor kappa B (NF-κB) signaling pathway in the small intestine of mice with cyclophosphamide-induced immunosuppression were investigated. Results: The peptide compositions from E. japonicus and G. max were quite different. Only 11% of the peptide sequences were identical between them. Administration of the peptides from E. japonicus and G. max at 300 mg/kg mb for 30 d could significantly increase the spleen index and thymus index, alleviate intestinal mucosal damage, increase the length of intestinal villi and decrease the depth of crypts in cyclophosphamide-induced immunosuppressed mice. Moreover, the inhibitory effect of cyclophosphamide on the expression of tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), interleukin-4 (IL-4), and IL-13 was ameliorated, and the secretion of IgA and secretory IgA and the gene expression of TLR-4, TLR-6, TLR-9 and NF-κB were upregulated in the small intestine mucosa. Conclusion: The peptides from E. japonicus and G. max can promote the secretion of immune factors and immunoglobulins in the small intestinal mucosa and alleviate cyclophosphamide-induced intestinal mucosal damage and immunosuppression in mice by protecting the TLRs/NF-κB signaling pathway. Although the average molecular masses, amino acid compositions and polypeptide compositions of the two peptides are different and the protective effect of the peptides from E. japonicu on secretory IgA in the intestinal mucosa is more pronounced than that of the peptides from G. max, there is no significant difference between their efficacy in protecting intestinal mucosal structure and regulating mucosal immunity in mice.

In this work, a new composite photocatalyst was synthesized by flower-like Bi2O3 and two-dimensional multilayer V2C using a facile hydrothermal method. Compared with the pristine sample, the specific surface area of Bi2O3/V2C MXene composite is significantly increased, which is favourable to improve the photocatalytic efficiency. The analysis of the UV-vis absorption spectrum and band gap energy shows that the construction of heterojunction broadens the light response range, improves the light absorption capacity, and obtains a narrower band gap than any of the single component, which is beneficial to the utilization of light. PL, TPC and EIS analysis revealed that Bi2O3/V2C MXene composite had stronger carrier mobility, which further confirmed that the photocatalytic oxidation performance of the system was the dominant reason in the photocatalytic NO pollutant removal process. This study provides a new idea for better understanding the two-dimensional MXene material-based photocatalyst and improving the NO removal efficiency. [ABSTRACT FROM AUTHOR]

Background Heterotopic gastric mucosa in the upper esophagus (HGMUE) is reported to be related to gastroesophageal reflux disease (GERD). This study investigated the prevalence of GERD and the use of salivary pepsin to diagnose gastroesophageal reflux, especially proximal reflux, in HGMUE patients. Methods One hundred and fifty-three HGMUE patients and 50 healthy volunteers were studied. All subjects took a reflux symptom index questionnaire (RSI); underwent endoscopy, barium esophagogram, high-resolution manometry (HRM), and 24-hour multichannel intraluminal impedance-pH-metry (MII-pH); and salivary pepsin test. Results Ninety-five (62.1%) HGMUE patients but no control subjects were diagnosed with GERD. The salivary pepsin concentration, RSI score, DeMeester score, acid exposure time (AET), total reflux episodes, proximal acidic reflux episodes, and proximal weakly acidic reflux episodes were significantly higher in the HGMUE group than in the control group (P  < 0.05). The salivary pepsin test showed a sensitivity of 85.9% and specificity of 56.9% for diagnosing GERD using the optimal cut-off value of 75 ng/mL. One hundred and seven (69.9%) and 46 (30.1%) HGMUE patients were categorized as pepsin (+) and pepsin (−), respectively when 75 ng/mL was used as a cut-off value. Male sex, RSI, AET, and proximal acid reflux episodes were positive predictive factors for the occurrence of pepsin (+) in HGMUE patients. Conclusions GERD, especially GERD with proximal acid reflux and related symptoms, was common in HGMUE patients. The salivary pepsin test could be an additional useful test for testing reflux in HGMUE patients, but it will not replace the MII-pH. [ABSTRACT FROM AUTHOR]

Ovarian cancer is a type of common gynecological tumors with high incidence and poor survival. The anticancer effects of the traditional Chinese medicine Solanum lyratum Thunb (SLT) have been intensively investigated in various cancers but in ovarian cancer is rare. The current study is aimed at investigating the effect of SLT on ovarian cancer cells. Lactate dehydrogenase (LDH) and MTT assays indicated that SLT concentrations of 0.25 and 0.5 μg/mL were not cytotoxic and had significant inhibitory effects on the cell viabilities of A2780 and SKOV3 cells, hence were used for subsequent experiments. Flow cytometric and western blot analysis revealed that SLT effectively suppressed ovarian cancer cell proliferation via inducing cell cycle arrest and increasing apoptosis. Cell cycle and apoptosis-related protein expressions were also regulated in SLT-treated cells. Moreover, DCFH-DA and western blot assays demonstrated that SLT enhanced ROS accumulation and subsequently activated the p53 signaling pathway. However, SLT-regulated ovarian cancer cell proliferation, apoptosis, migration, invasion, and EMT were significantly reversed by an ROS inhibitor (NAC, N-acetyl-L-cysteine). Furthermore, A2780 and SKOV3 cells cocultured with M0 macrophages showed that SLT activated the polarization of M0 macrophages to M1 macrophages and inhibited the polarization to M2 macrophages, with the increased percentage of CD86+ cells and decreased percentage of CD206+ cells were detected. In summary, this study illustrated the anticancer effects of SLT on ovarian cancer cells, suggesting that SLT may have the potential to provide basic evidence for the discovery of antiovarian cancer agents. [ABSTRACT FROM AUTHOR]