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A novel flame retardant containing Si, N, and S elements, ((2-(triethoxysilyl)ethyl)thio)ethan-1-amine hydrochloride (TETEA), was synthesized via a click reaction and characterized using nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FTIR). Subsequently, the flame-retardant cotton fabric was fabricated by sol-gel method. The results indicated that TETEA was successfully loaded on cotton fabric and formed a uniform protective layer on the surface of cotton fabric, exhibiting excellent flame retardancy. The flame-retardant cotton fabric achieved limiting oxygen index (LOI) of 28.3 % and passed vertical combustion test without after-flame or afterglow time at TETEA concentration of 500 g/L. Thermogravimetric analysis revealed that the residual carbon content of the flame-retardant cotton fabric was much higher than that of the control under air and N 2 conditions. Besides, the flame-retardant cotton fabric was not ignited in cone calorimeter test with an external heat flux of 35 kW/m2. The peak heat release rate and the total heat release decreased from 133.4 kW/m2 to 25.8 kW/m2 and from 26.46 MJ/m2 to 17.96 MJ/m2, respectively. This phosphorus-free flame retardant offers a simplified synthesis process without adverse environmental impacts, opening up a new avenue for the development environmentally friendly flame retardants compared to traditional alternatives. • A new phosphorus-free flame retardant was synthesized under solvent-free conditions. • The preparation process was simple, cost-effective and environmentally friendly. • Cotton fabric achieved the LOI of 28.3 % and passed vertical combustion test. • The hydrophobicity of the flame-retardant cotton fabric was also enhanced. [ABSTRACT FROM AUTHOR]

Effect of Nigella sativa seed polysaccharides (NSSP) on type 2 diabetic mice and its gut microbiota was investigated on the type 2 diabetic mice model feed by high-fat diet. Fasting blood glucose (FBG), biochemical parameters, expression levels of cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and phosphor-AKT (p-AKT) protein, membrane glucose transporter 4 (GLUT4) in skeletal muscles, as well as the change of gut microbiota profile in mice model were measured. Results showed that the high-dose NSSP could significantly lower the levels of FBG, glycosylated serum protein (GSP), triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), malondialdehyde (MDA), TNF-α, IL-6 and IL-1β, and significantly increased insulin (INS), high-density lipoprotein cholesterol (HDL C), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT) and the expression levels of p-AKT and GLUT4 in mice. Besides, the high-dose NSSP has significantly increased the abundance of f_Muribaculaceae_Unclassified and Bacteroides , which were significantly suppressed in the mice gut after the treatment of streptozotocin (STZ). These results indicated that NSSP could improve the abnormal state of diabetic mice by regulating the PI3K/AKT signaling pathway with simultaneous changes of the gut microbiota profile. [ABSTRACT FROM AUTHOR]

Abstract Two novel polysaccharides were obtained from flowers of Apocynum venetum L., and named as Vp2a-II and Vp3. Their average molecular weights were 7 kDa and 9 kDa, respectively. Methods of monosaccharide analysis, acid hydrolysis and methylation analysis, Fourier transform-infrared spectroscopy (FT-IR), gas chromatography–mass spectrometry (GC–MS) and nuclear magnetic resonance (NMR) spectroscopy were used to identify the structure of Vp2a-II and Vp3. Vp2a-II was composed of →6)- β - d -Glc p -(1 → 6)- α - d -Gal p -(1→ residues. Vp3 was composed of α - d -Glc p A-(3 → α - d -Gal p A residues. The anticoagulant activity was evaluated by activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) assays in vitro. Results indicated that Vp3 exhibited the anticoagulant activity. [ABSTRACT FROM AUTHOR]