Ganoderma polysaccharide and chitosan synergistically ameliorate lipid metabolic disorders and modulate gut microbiota composition in high fat diet-fed golden hamsters

High-fat diet (HFD) and sucrose intake can lead to hyperlipidemia, hypercholesterolemia, and nonalcoholic fatty liver disease (NAFLD) as well as disturbed gastrointestinal microbiota and dysfunctional intestinal barrier. In the present study, we showed that Ganoderma lucidum polysaccharide and chitosan (PC) significantly mitigated the hyperlipidemia in HFD-fed hamsters via lowering the contents of serum total triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and aspartate aminotransferase (AST). Furthermore, PC changed the composition of gastrointestinal microbiota and elevated the relative abundances of beneficial bacteria, such as Prevotella, Oscillibacter, and SCFA-producers. Interestingly, we also found that the abundances of Prevotella, Alloprevotella, Bifidobacterium, and Alistipes were negatively associated with serum lipid profiles. Collectively, the above-mentioned findings indicated that PC could improve lipid metabolic disorders, at least in part, by modulating gastrointestinal microbiota, suggesting that PC could be used as a potential lipid-lowering ingredient in functional foods. PRACTICAL APPLICATIONS: PC could ameliorate lipid metabolism disorder, at least in part, by regulating specific gut microbiota, suggesting its potential as a novel lipid-lowering ingredient in functional foods. We believed that our findings could be of interest to the readers because they help others further understand the gut microbiota alterations that occurred after PC supplementation in the context of metabolic syndrome (MetS).

Polyunsaturated fatty acids from microalgae Spirulina platensis modulates lipid metabolism disorders and gut microbiota in high-fat diet rats

Effects of Spirulina platensis 55% ethanol extract (SPL55) on lipid metabolism in high-fat diet-induced hyperlipidaemic rats were investigated. Ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry indicated that SPL55 was enriched with polyunsaturated fatty acids. Meanwhile, serum and liver lipid levels, including total triglyceride, total cholesterol, and low-density-lipoprotein cholesterol, were significantly decreased in hyperlipidaemic rats of SPL55. Analysis of tissue sections showed that SPL55 treatment could markedly inhibit hepatic lipid accumulation and steatosis. Moreover, SPL55 regulated the mRNA and protein expression levels of SREBP-1c, HMG-CoA, PEPCK, ACC, and AMPK genes involved in lipid metabolism. Furthermore, SPL55 led to decrease the abundances of Turicibacter, Clostridium_XlVa, and Romboutsia, which were positive correlation with lipid metabolism indicators, and has also enriched Alloprevotella, Prevotella, Porphyromonadaceae, and Barnesiella. These results provided evidence that SPL55 might be developed as a functional food to ameliorate lipid metabolic disorders and hyperlipidaemia.

Preparation of Z-L-Phe-OH-NBD imprinted microchannel and its molecular recognition study

An integrated microchip was presented for selective recognition of Z-L-Phe-OH-NBD, using molecular imprinting technique. Molecularly imprinted polymer (MIP) were prepared by copolymerization in the presence of template molecule Z-L-Phe-OH-NBD, in which methacrylic acid and 4-vinylpyridine were used as functional monomers and ethylene dimethacrylate used as crosslinker. Imprinted polymer particles were introduced into a microchannel fabricated with a new material i.e. poly(methylvinylsiloxane) by simply rapid prototyping method. Imprinted effects were evaluated by laser-induced fluorescence (LIF) detection where the results indicated that good selective recognition for Z-L-Phe-OH-NBD in the imprinted polymer was obtained; the adsorption percentage of Z-L-Phe-OH-NBD was 61%. In contrast to conventional molecular imprinting analysis, integration shortened overall analysis time from 4h to 10 min.

Immunosorbent assay microchip system for analysis of human immunoglobulin G on MagnaBind™ carboxyl derivatized beads

An immunosorbent assay system was integrated into a PMVS microchip. MagnaBind carboxyl derivatized beads were introduced into a microchannel, and then human immunoglobulin G (IgG) was bound to the bead surface in the microchannel of the chip. Immunoreaction was conducted in the microchannel for the bead-bounded antigen IgG with the antibody FITC-labelled IgG. On-chip detection was performed using a laser-induced fluorescence (LIF) system. The integration shortened the overall analysis time from 7 h to less than 40 min.

Solid-substrate room-temperature phosphorescence study on zinc(II) and tin(IV) protoporphyrins and their interaction with DNA

The solid-substrate room-temperature phosphorescence (SS-RTP) of two commercially available metalloporphyrin compounds, zinc(II) protoporphyrin (ZnPP) and tin(IV) protoporphyrin (SnPP) has been studied. Strong and stable RTP signals of the two metalloporphyrins in neutral to weakly basic solutions can be simply induced on filter paper without addition of external heavy atom perturbers. Their emission bands appeared at 723 nm for ZnPP and 718 nm for SnPP at an excitation wavelength of 417 nm. Compared with SnPP, ZnPP is a better RTP probe for DNA because its RTP enhancement effect is much higher under the same experimental conditions. The interaction of ZnPP with DNA at pH 8.5 gives an apparent binding constant of 9.1 x 10(3) which is similar to that of the cationic porphyrin absorption probe CuTMPyP (copper (II)- tetrakis(4-N-methylpyridyl)porphine complex). Hydrogen bonding between the monocarboxylic acid substituent of ZnPP and the base pairs of DNA plays a crucial role in the binding.

Determination of photophysical rate constants for the non-protected fluid room temperature phosphorescence of several naphthalene derivatives

The determination of kinetic parameters for luminescence processes is very important in understanding the phosphorescence process and the mechanisms of the heavy atom effect (HAE). In our previous work, we reported that room temperature phosphorescence (RTP) emission of many naphthalene derivatives can be induced directly from their aqueous solution without using any kind of protective medium, and the name Non-Protected Fluid Room Temperature Phosphorescence (NP-RTP) is suggested for this new type of RTP emission. In order to further understand this kind of luminescence phenomenon, the influence of heavy atom perturber (HAP) concentration on RTP lifetime of several naphthalene derivatives was studied in detail in this paper. The possibility of determination of photophysical parameters for emission of NP-RTP was explored based on the definition on the phosphorescence lifetime and the relation with the concentration of HAP in this paper. A static Stern-Volmer equation for phosphorescence was derived and the luminescence kinetic parameters were calculated. The results obtained by two different ways proved that photophysical parameters for RTP emission can be determined based on the changes of the RTP lifetime.

Boronic acid fluorophore/beta-cyclodextrin complex sensors for selective sugar recognition in water

A novel boronic acid fluorophore 1/beta-cyclodextrin (beta-CyD) complex sensor for sugar recognition in water has been designed. The probe 1 bearing pyrene moiety as a fluorescent signal transducer exhibits no fluorescence emission, due to its aggregation in water containing 2% DMSO; however, the addition of beta-CyD to this solution largely changes UV-vis and fluorescence spectra of 1 by forming an inclusion complex with beta-CyD, and an efficient fluorescence emission response of 1/beta-CyD complex upon sugar binding is found to be obtained at pH 7.5. The pH-fluorescence profile of the 1/beta-CyD complex reveals that the boronate ester formation with fructose induces the apparent pKa shift from 7.95+/-0.03 in the absence of fructose to 6.06+/-0.03 in the presence of 30 mM fructose, resulting in the fluorescence emission response under the neutral condition. The spectral properties of 1 in 95% methanol:5% water (v/v), as well as the fluorescence quenching study of 1-methylpyrene with 4-methoxycarbonylphenyl-boronic acid 2, demonstrate that the response mechanism is based on the photoinduced electron transfer (PET) from the pyrene donor to the acid form of phenylboronic acid acceptor in 1, and thus, the proton dissociation of phenylboronic acid induced by sugar binding inhibits the PET system while increasing the fluorescence intensity of the pyrene moiety. To evaluate the binding ability and selectivity of the 1/beta-CyD complex for monosaccharides in water, the response equilibria have been derived. The 1:1 binding constants of the 1/beta-CyD complex obtained from the equilibrium analysis are in the order: D-fructose (2515+/-134 M(-1)) >> L-arabinose (269 +/- 28 M(-1)) > D-galactose (197+/-28 M(-1)) > D-glucose (79+/-33 M(-1)), which is consistent with the binding selectivity of phenylboronic acid.