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Study of the positive effects of LMET-SFP in high-fat diet and streptozotocin-induced diabetic rats, and the underlying mechanisms of LMET-SFP as compared to metformin alone in managing diabetes.

MPP could improve diabetes by remodeling intestinal flora and regulating gene expression related to glycolipid metabolism.

The aim of the current work was to investigate the anti-diabetic effects and underlying mechanisms of Undaria pinnatifida polysaccharides (UPP) based on a type 2 diabetes (T2DM) rat model. The starch loading test showed that UPP administration could reduce blood glucose fluctuations caused by eating. Analysis of diabetic symptoms and biochemical profiles showed that UPP intervention markedly decreased fasting blood glucose level, mitigated insulin resistance, improved glucose tolerance, dyslipidemia and liver and kidney damage in diabetic rats. The 16S rRNA analysis demonstrated that UPP intervention could markedly change the intestinal microflora composition, causing increases in Alistipes, Bacteroides, Christensenellaceae_R-7_group, Desulfovibrio, Muribaculaceae_norank, Ruminococcaceae_UCG-013, and Ruminococcaceae_UCG-014, and a decrease in Escherichia-Shigella. Furthermore, RT-qPCR analysis results clarified that UPP administration distinctly activated the IRS/PI3K/AKT signaling pathway, restrained PEPCK, G-6-Pase and Egr-1 genes, and affected the relative expression of HMGCR and LDLR genes. This study demonstrates that UPP could be applied as an adjuvant agent for the management of T2DM.

The objective of current work was to explore the potential anti-diabetic mechanisms of Hizikia fusifarme polysaccharide (HFP) in type 2 diabetic rats. The carbohydrate loading experiment illustrated that HFP supplement could reduce blood sugar fluctuations caused by eating through inhibiting the hydrolysis of starch in mice. The analysis of typically diabetic symptoms and serum profiles showed that oral administration of HFP could mitigate hyperglycemia, insulin resistance, dyslipidemia, chronic inflammation and oxidative stress in rats. The 16s rRNA gene sequencing analysis indicated that HFP treatment could restore beneficial composition of gut flora in diabetic rats, and the correlation analysis revealed that the improvement of diabetes is closely related to the modification of gut flora by HFP intervention. Furthermore, the RT-qPCR and western blotting analysis clarified that HFP administration could increase glycogen storage in liver and skeletal muscle of diabetic rats through activating IRS/PI3K/AKT/GLUT signaling pathway and restrain gluconeogenesis via affecting the relative expression of Egr-1 and PEPCK genes.

Three algal polysaccharides (APs) were acquired from Scagassum (SCP), Sargassum fusiforme(Harv.) Setch. (SFP) and Macrocystis pyrifera(L.)Ag. (MAP) by hot water extraction, and their structural characterization and antidiabetic activity were investigated in high fat diet and streptozotocin-induced type 2 diabetic rats. The results revealed that there were obvious differences in extraction yield, molecular weight, compositions of monosaccharide and organic element, molecular morphology, rheological properties and the contents of total sugar, protein, uronic acid and sulfate of SCP, MAP and SFP. SFP had the highest extraction yield, the contents of total sugar and uronic acid and the smallest molecular weight. Congo red assay indicated that all polysaccharides had no triple-helix structure. Oral administration of APs prominently restrained loss of weight and increase of water intake (P .05), and also significantly controlled the increase of levels of blood glucose, triglyceride (TG) and total cholesterol (TC) in diabetic rats (P 0 .05). Diabetic rats treated with SCP had the highest high density lipoprotein cholesterol (HDL-C) level (P .05), similar to those in normal group. MAP and SCP showed positive effect in improving the low density lipoprotein cholesterol (LDL-C) level of diabetic rats (P .05). Meanwhile, the increased ALT and BUN contents caused by the liver and kidney damages were markedly ameliorated in the diabetic rats with APs intervention (P .05). As a consequence, APs could be promising candidates as natural medicines and functional foods for the improvement of diabetes and its complications.

The aim of the current work was to investigate the anti-diabetic effects and underlying mechanisms of

Sargassum fusiforme polysaccharides (SFPs), including SFP-3-40, SFP-3-60, SFP-3-80, SFP-7-40, SFP-7-60, SFP-7-80, SFP-10-40, SFP-10-60, and SFP-10-80, were extracted at different pH (3, 7, and 10), and then precipitated with graded precipitation of 40%, 60% and 80% (v/v) ethanol solution, respectively. Their physicochemical properties and α-glucosidase inhibitory activity were determined. Results showed that SFPs significantly differed in the contents of total sugar, protein, uronic acid, sulfate, the zeta potential, and molecular weight distribution. SFPs, including SFP-10-40, SFP-10-60, and SFP-10-80, had bigger absolute zeta potential value and higher respective average molecular weight in the same ethanol concentration precipitate. All samples were mainly composed of fucose, glucuronic acid, and mannose with different molar ratios. The extraction pH and precipitation ethanol solution concentration caused little changes in functional groups, but significantly altered surface morphology of SFPs. Congo red test revealed that all polysaccharides were not helical polysaccharides. Rheological measurements indicated that SFPs were pseudoplastic fluids and showed elastic behavior of the gel. Except SFP-3-40 and SFP-3-60, all other samples had a stronger α-glucosidase inhibitory activity than that of acarbose. The inhibition type of SFPs against α-glucosidase varied owing to different extraction pH and precipitation ethyl concentration. This study shows that extraction pH can significantly affect the structure and hypoglycemic activity of SFPs and provide a data support for the scientific use of Sargassum fusiforme in industrial production.

In the current study, a functional polysaccharide fraction (HFP) was obtained from Hizikia fusiforme by ultrasound-assisted enzymatic extraction, and its structural characterization and hypoglycemic activity and potential molecular mechanism were investigated. The results indicated that HFP with high uronic acid was a heterogeneous polysaccharide composed of six monosaccharides. Congo red test explained that HFP had no triple helix conformation. AFM analysis revealed that HFP was spherical particle with flame-like aggregates and multiple strands closely arranged. Rheological analysis showed that HFP exhibited shear-thinning flow behavior. HFP significantly ameliorated diabetes-related symptoms and serum profiles and increased muscle glycogen storage in rats. HFP administration at 400 mg/kg body weight/day displayed greater advantages than metformin in controlling the levels of fasting blood glucose, triglyceride (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bile acid (TBA) of diabetic rats. Intervention of HFP up-regulated markedly the expression of AMPK-α, GLUT4, PI3K and Akt in skeletal muscle of diabetic rats at the mRNA and protein levels, revealing hypoglycemic effects of HFP may be related closely to improving insulin resistance and mitochondrial function of skeletal muscle.

Sargassum fusiforme polysaccharides (SFP), an anti-digestive biologically active ingredient obtained from Sargassum fusiforme by ultrasound-assisted enzymatic extraction, have been proven to exhibit extremely strong alpha-glucosidase inhibitory activity. In the current research, the potential anti-diabetic effects and molecular mechanisms of SFP were investigated by classic biochemical analysis, high-throughput sequencing and molecular biology techniques in type 2 diabetic rats. The analysis of typical diabetic symptoms and serum profiles showed that oral administration of SFP could mitigate hyperglycemia, hyperinsulinemia, dyslipidemia and oxidative stress in diabetic rats. SFP also promoted glycogen synthesis in the liver and skeletal muscles. H&E staining observation confirmed that SFP intervention could partially repair liver and muscle injuries caused by diabetes. Moreover, 16S rRNA gene sequencing analysis indicated that SFP treatment could distinctly restore the beneficial composition of gut flora in diabetic rats. Furthermore, RT-qPCR analysis revealed that anti-diabetic effects of SFP may be closely related to accelerating the absorption and utilization of blood glucose in the liver and muscle and inhibiting hepatic glucose production. In short, this study demonstrated that SFP could be developed as functional foods or pharmaceutical supplements for the prevention or mitigation of diabetes and its complications.

Three algae polysaccharides (APs) extracted from Ascophyllum nodosum (ANP), Fucus vesiculosus (FVP) and Undaria Pinnatifida (USP) significantly differed in the zeta potential, water and oil holding capacity, monosaccharide composition, organic element composition, molecular weight distribution, microstructure and rheological properties. Antidiabetic effects of APs were compared by oral intervention at the dose of 400 mg/kg·body weight/day in high sugar and fat diets and streptozotocin injection induced type 2 diabetic rats. The analysis of body weight, water intake, fasting blood glucose, insulin, oral glucose tolerance, blood lipid indicators (including total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) and free fatty acid (FFA)), liver function indexes (involving alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) and renal function profiles (comprising uric acid (UA) and urea nitrogen (BUN)) showed that APs possessed obvious antidiabetic activities, and FVP showed better effects in controlling the levels of FFA, AST, ALT, UA and BUN. Intervention of FVP reduced the total bile acid (TBA) level and elevated high density lipoprotein cholesterol (HDL-C) level of diabetic rats. Histomorphological observation further demonstrated that APs, especially FVP, could attenuate liver and kidney damage caused by diabetes. This study concluded that the antidiabetic effects of ANP, FVP and USP were distinctly different, which might be attributed to their different chemical structures. Therefore, the structure-activity relationship and antidiabetic mechanism of APs will be our future research direction.

Two polysaccharide fractions (SFPs, designated as respectively SFP-1 and SFP-2) were acquired from Sargassum fusiforme by ultrasound-assisted enzymatic extraction, and their physicochemical properties and hypoglycemic and hypolipidemic effects were investigated. Structural analysis indicated that SFPs were obvious different in the zeta potential, molecular weight distribution, characteristic organic group, microstructure and the contents of total sugar, uronic acid, sulfate and moisture. SFPs consisted of fucose, mannose, rhamnose, glucose, galactose and glucuronic acid with different molar ratios. Congo red test explained that SFPs had no triple-helix structure. SFP-1 exhibited lower viscosity due to its lower molecular weight. Regarding to hypoglycemic and hypolipidemic effects, oral administration of SFPs prominently restrained loss of body weight and increase of water intake, and also significantly controlled the increase of levels of fasting blood glucose, triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), uric acid (UA), urea nitrogen (BUN), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) of diabetic rats, and SFP-2 showed better effects in controlling fasting blood glucose, ALT, UA and BUN levels. Intervention of SFP-2 reduced the levels of insulin, FFA and TBA of diabetic rats. Histomorphological observation further demonstrated that SFPs could attenuate liver and kidney damage caused by hyperglycemia and hyperlipidemia. Data indicated that SFPs, especially SFP-2, significantly improved hyperglycemia, hyperlipidemia and liver and kidney function of diabetic rats.

This study aimed to investigate the effects of 95% ethanol extract of G. frondosa (GF95) on lipid metabolism and gut microbiota composition in high-fat diet (HFD) fed rats. UPLC/Q-TOF MS indicated that GF95 was enriched with flavones, fatty acids and so on. Meanwhile, we found that body weight, serum lipid or liver index (total cholesterol, triglyceride, and low density lipoprotein cholesterol) levels were significantly decreased in GF95-treated HFD-fed rats. Furthermore, GF95 treatment regulated mRNA expression levels involved in lipid metabolism. GF95 consumption significantly enhanced the excretion of bile acids in the cecum. Besides, in this study, a higher abundance of Butyricimonas genus was revealed in the GF95 group, which is highly related to the highest production of short-chain fatty acids in the caecum contents among the experimental groups. Interestingly, results from network analysis showed that Butyricimonas were negatively correlated with serum and liver lipid profiles.

Teramethylpyrazine (TMP) is a pyrazine alkaloid with a variety of pharmacological effects and widely used in clinical practice. In this study, Monascus strain M-3 with high TMP and low citrinin productions was screened from red yeast rice collected from different areas of Fujian province in China. Monascus strain M-3 was further identified through molecular biological methods based on the sequencing of different gene regions. Results showed that primer set of β-tubulin-F/β-tubulin-R targeting the β-tubulin gene was more suitable for the identification of Monascus strain M-3. Based on comparative analysis of the results obtained by different primer sets, Monacus strain M-3 was finally identified as Monascus purpureus. Then, the composition of culture medium and liquid state fermentation conditions of Monacus strain M-3 were optimized by single-factor experiment and central composite design of response surface methodology, with the purpose of optimizing the TMP productions. The optimum composition of culture medium and liquid state fermentation conditions are as follows: starch 5.1%, peptone 3.51%, Mg2SO4 0.1%, NaNO3 0.2%, KH2PO4 0.25%, fermentation temperature of 28.23 °C, fermentation time of 9 d, shaker speed of 180 r/min, inoculum size of 7.21% and loading volume of 100 mL/250 mL triangular flask. Under the optimum composition of culture medium and liquid state fermentation conditions, the TMP production of Monacus strain M-3 can reach 13.49 µg/mL. This study is expected to provide a new approach of TMP production through biosynthesis by Monascus strain, and promote the further development of functional foods or medicines from Monascus fermentation products.

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.

The main goal of this work was to investigate the bacterial flora present in the traditional fermentation starters using matrix-assisted laser desorption/ionisation time of flight (MALDI-TOF) mass spectrometry fingerprinting combined with 16S rRNA gene sequencing and species-specific PCRs. A total of 1314 bacterial strains were obtained from ten kinds of representative wine fermentation starters (5 Hong Qu and 5 Yao Qu) and classified by MALDI-TOF mass spectrometry. Sixteen different bacterial species belonging to six different genera (Bacillus, Staphylococcus, Leuconostoc, Pediococcus, Lactobacillus and Lactococcus) were identified with high accuracy by comparing them with generated spectra of MALDI Biotyper database. Comparison of 16S rRNA gene phylogeny and MALDI-TOF mass spectrometry analysis showed that MALDI-TOF mass spectrometry fingerprinting was a good complementary approach to 16S rRNA sequencing and even a more powerful tool in the accurate differentiation and classification of Bacillus species, especially for differentiating between Bacillus subtilis, Bacillus amyloliquefaciens and Bacillus methylotrophicus. MALDI-TOF mass spectrometry was also found to provide valuable information at species levels for the genus of Lactobacillus. The identification revealed that most strains isolated from traditional fermentation starters were B. amyloliquefaciens (31.81%), followed by Bacillus megaterium (16.89%), Lc. lactis subsp. lactis (8.60%) and B. subtilis (8.14%). In the culture-dependent quantitative analysis, 69.01% of the detected isolates were Bacillus species, and 30.44% of the detected isolates belonged to the class of lactic acid bacteria (LAB), including Leu. mesenteroides, Pediococcus pentosaceus, Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, Pediococcus acidilactici, Lactobacillus coryniformis and Lc. lactis subsp. lactis. This study provides detailed evaluation of bacterial communities in the traditional fermentation starters for Hong Qu glutinous rice wine using a fast and cost-effective technique—MALDI-TOF mass spectrometry fingerprinting. Information provided by this study is fundamental and useful to develop effective strategies for the selection of beneficial bacterial strains and improve of quality of Hong Qu glutinous rice wine.

In this study, reverse transcription quantitative real-time PCR (RT-qPCR) assays using species-specific primers were developed for the quantification of the three major fungal species (Saccharomycopsis fibuligera, Rhizopus oryzae, and Monascus purpureus) during the traditional brewing of Hong Qu glutinous rice wine. Species-specific primers (Sfi-F/Sfi-R, Ro-F/Ro-R, and Mp-F/Mp-R) targeting the ITS-5.8S rRNA gene and the beta-tubulin gene sequences were designed and their specificity was evaluated by RT-qPCR with the total RNA from fungal species closely related to the traditional brewing of Hong Qu glutinous rice wine. Results of RT-qPCR using species-specific primers showed 100 % inclusivity (positive signal in the presence of target complementary DNA (cDNA)) and 100 % exclusivity (negative signals in the presence of non-target template). The specificity of each primer set was also tested when the target cDNA was mixed with non-target cDNA, and results showed that there was no significant difference (P > 0.05) in threshold cycle (Ct) values obtained from pure target cDNA and target cDNA mixed with non-target cDNA. The detection limits of the established qPCR assays were determined to be 101 gene copies/μL for S. fibuligera and 102 gene copies/μL for R. oryzae and M. purpureus, respectively. Good correlations were obtained for the tested species between 102 and 108 gene copies/μL by qPCR analysis. Finally, the established RT-qPCR assays were applied to quantify viable S. fibuligera, R. oryzae, and M. purpureus during the traditional brewing of Hong Qu glutinous rice wine. This study standardized the RT-qPCR assays for dominant fungi associated with the traditional brewing of Hong Qu glutinous rice wine, and it also proved the usefulness of RT-qPCR assays for the quantification of live cells in multi-species samples. Results would show great value in scientifically understanding of the brewing mechanism of Hong Qu glutinous rice wine.

The aim of this study was to investigate the bacterial and fungal community structure and dynamics during the traditional brewing of Fuzhou Hong Qu glutinous rice wine through culture-dependent and culture-independent methods. The culture-independent DGGE profiles revealed the presence of eleven bacterial species (Janthinobacterium lividum, Lactobacillus plantarum, Weissella soli, Leuconostoc mesenteroides, Lactobacillus brevis, Pediococcus pentosaceus, Lactococcus lactis subsp. lactis, Pediococcus acidilactici, Bacillus subtilis, Bacillus aryabhattai and Bacillus megaterium) and seven fungal species (Saccharomycopsis fibuligera, Pichia guilliermondii, Saccharomyces cerevisiae, Wickerhamomyces anomalus, Rhizopus oryzae, Candida glabrata and Monascus purpureus) during the traditional brewing process. Furthermore, the microbial compositions of fermented samples were investigated using culture-dependent approach (conventional plate count technique combined with molecular identification). Results showed that the relative proportions of some fungal species (C. glabrata, W. anomalus, P. guilliermondii and S. fibuligera) and bacterial species (Lc. lactis subsp. lactis, Staphylococcus pasteuri, Bacillus sp., P. pentosaceus) detected at the early brewing stage decreased as the fermentation progressed, while S. cerevisiae, L. brevis, L. plantarum and Lactobacillus paracasei became the predominant species during the late brewing period. Some differences were also found between the profiles obtained by PCR–DGGE and culture-dependent technique. Comparative analysis revealed that some species (J. lividum, W. soli, B. aryabhattai and P. guilliermondii) could only be detected using PCR–DGGE technique. Conversely, some species (L. paracasei, S. pasteuri, Bacillus methylotrophicus, Mucor indicus and Aspergillus flavus) could only be detected by culture-dependent method. Therefore, the combination of culture-dependent and -independent approaches is quite necessary because they provided complementary information about the composition of the microbial community during the traditional brewing of Fuzhou Hong Qu glutinous rice wine. This study provides the first detailed evaluation of fungal community and dynamics in Fuzhou Hong Qu glutinous rice wine traditional brewing process using culture-dependent and -independent methods, which would facilitate scientific understanding of the traditional brewing mechanism and be useful for the selection of the suitable and beneficial strains to improve the wine quality.

Monascus spp. have been used for thousands of years as a traditional food additive in China. This mold can produce many different types of commercially valuable secondary metabolites of biological activity. Soluble starch and glycerol are the two principal carbon sources universally utilized by Monascus for the production of beneficial metabolites. In this study, the effects and regulation mechanisms of soluble starch and glycerol for M. purpureus FAFU618 on Monascus azaphilone pigments (MonAzPs) were investigated through ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-QTOF-MS/MS), comparative proteomics and quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR). The production of intracellular and extracellular pigments was significantly different between the soluble starch group (SSG) and glycerol group (GCG). Additionally, the components of intracellular pigments revealed by UPLC-QTOF-MS/MS showed that Monascin and Ankaflavin increased significantly in the GCG, while Rubropunctatin and Monascorubrin increased in the SSG. Differentially expressed proteins of mycelia between SSG and GCG were analyzed by two-dimensional gel electrophoresis (2-DE) and MALDI-TOF/TOF MS. We identified 27 proteins with statistically altered expression, of which 18 proteins associated with the EMP (glycolytic pathway), translation, energy generation, proteolysis, etc. were up-regulated, and 9 proteins, including ribosomal proteins, heat shock proteins (HSPs) and others, were down-regulated in GCG. Meanwhile, the expression levels of MonAzP biosynthetic genes were also analyzed by RT-qPCR, and the results showed that mppA, mppC, mppR1 and mppR2 were down-regulated, whereas genes MpPKS5, MpFasA2, MpFasB2, mppB, mppD and mppE were up-regulated. Collectively, these findings illustrate that the regulation of MonAzPs is not only closely related to the expression levels of certain proteins in the polyketide synthesis pathway but also closely related to the concentration of primary metabolism-generated molecules that are used as substrates for polyketide synthesis. The present study provides insights into the regulation of different carbon sources on the metabolism of MonAzPs in M. purpureus FAFU618. These results may promote further development of functional foods or medicines from Monascus spp. fermented products.

It is important to study the pressure distribution on the blade and in the adjacent area while searching the power augmentation theory with adding a tip vane to the wind turbine. This paper shows the CFD simulation relationship of the pressure distribution on the rotor blade and in the adjacent area, after calculating the pressure of the different chordwise and spanwise point on the blade with the tip vane-V(8.8×8) and without the tip vane under tip speed ratio λ 4.5. Combining the isobaric section figure in certain location, it can be seen that the tip vane improve the pressure difference between pressure and suction surface. The most influenced zone is found and these can further display the power augmentation theory of the wind turbine using the tip vane. The simulation calculation was based on N-S equations. 3-D, steady, implicit solver was chosen. Turbulence model was k-ω SST. Discretization scheme is SECOND ORDER UPWIND. Pressure-velocity coupling was a typical SIMPLE scheme. In the whole grid system, two-divided grid formation was adopted, that is, inner region and outer region. Inner region including rectangular solid blade and neighboring, outer region is semi-cylinder. There were together 720,000 nodes with tetra-prism unstructured mesh.

It is proved that a tip vane can improve the wind turbine's efficiency by the test and CFD. In this paper, the performance of horizontal axis wind turbine and horizontal axis wind turbine with a tip vane by CFD were simulated. After comparing the velocity distribution around wind turbine blade with the tip vane-V(8.8×8) and without the tip vane and combining the velocity vectors figure of the certain location, the change of the velocity distribution around wind turbine blade and the weakening of the vortex around blade tip with the tip vane can be seen. These can further display the power augmentation theory of the wind turbine by the tip vane.