ABSTRACT
The instability of ester bonds, low water solubility, and increased cytotoxicity of flavonoid glycoside esters significantly limit their application in the food industry. Therefore, the present study attempted to resolve these issues through liposome encapsulation. The results showed that baicalin butyl ester (BEC4) and octyl ester (BEC8) have higher encapsulation and loading efficiencies and lower leakage rate from liposomes than baicalin. FTIR results revealed the location of BEC4 and BEC8 in the hydrophobic layer of liposomes, which was different from baicalin. Additionally, liposome encapsulation improved the water solubility and stability of BEC4 and BEC8 in the digestive system and PBS but significantly reduced their cytotoxicity. Furthermore, the release rate of BEC4 and BEC8 from liposomes was lower than that of baicalin during gastrointestinal digestion. These results indicate that liposome encapsulation alleviated the negative effects of fatty chain introduction into flavonoid glycosides.
Subject(s)
Esters , Flavonoids , Liposomes , Flavonoids/chemistry , Flavonoids/pharmacology , Flavonoids/administration & dosage , Liposomes/chemistry , Humans , Esters/chemistry , Solubility , Cell Survival/drug effects , Drug CompoundingABSTRACT
BACKGROUND: Chinese rice wine (CRW; a traditional alcoholic beverage in China with unique flavor and high nutritional value) containing high level of biogenic amines (BAs) may be deleterious to human health. The processes of rice soaking, primary fermentation and secondary fermentation were found to be the major factors for accumulation of BAs during industrial CRW production. RESULTS: To reduce the risk of the formation of BAs in CRW production, Enterococcus durans AR315, a BA-negative lactic acid bacterium, was isolated from CRW samples by PCR-based molecular marker reverse screening in this work. With addition of AR315 during steeping rice phase, the level of total BAs was significantly decreased by 45.1% in comparison with the control. Moreover, the final BA concentration with the addition of AR315 was 27.6% lower than that of the control during fermentation phase. CONCLUSIONS: To our knowledge, this is the first report of decreased accumulation of BAs in CRW production using a BA-negative lactic acid bacterium. Hence, using a BA-negative lactic acid bacterium as a starter culture could be an efficient strategy for significantly reducing the formation of BAs, which has the potential for industrial application in CRW production. © 2020 Society of Chemical Industry.
Subject(s)
Biogenic Amines/metabolism , Lactobacillales/metabolism , Oryza/microbiology , Wine/microbiology , Biogenic Amines/analysis , China , Fermentation , Lactobacillales/genetics , Lactobacillales/isolation & purification , Oryza/metabolism , Wine/analysisABSTRACT
The objective of this study was to explore the core functional microbiota for the production of volatile flavour during the traditional brewing of Wuyi Hong Qu glutinous rice wine, one of the most typical representatives of rice wine in China. Microbiological analysis based on high-throughput sequencing (HTS) technology demonstrated that bacteria of Lactobacillus, Bacillus, Leuconostoc, Lactococcus, Raoultella, Staphylococcus, Pediococcus, and Weissella, and fungi of Saccharomyces, Saccharomycopsis, Rhizopus, Monascus, Pichia, Wickerhamomyces, Candida, and Aspergillus were the predominant genera during the traditional fermentation process. Principal component analysis (PCA) based on the relative abundance showed that both of bacterial and fungal communities varied significantly in different fermentation phases. Some predominant microbial species or genera (including bacteria of Bacillus spp., Staphylococcus spp., Weissella spp., and P. acidilactici, and fungi of M. purpureus, R. oryzae, R. arrhizus var. arrhizus, and A. niger) were detected at the initial brewing stage, and their populations decreased as the fermentation progressed, while those of Lactobacillus, Gluconacetobacter, Leuconostoc, Pichia, Wickerhamomyces, and Saccharomyces increased to become the predominant genera at the final stage. A total of 79 volatile compounds were identified in traditional fermentation starters and during the traditional brewing process, mainly including esters, alcohols, acids, aldehydes, ketones, and phenols. Heatmaps and PCA also revealed the significant variances in the composition of volatile compounds among different samples. Furthermore, the potential correlations between microbiota succession and volatile flavour dynamics were explored through bidirectional orthogonal partial least squares (O2PLS) based correlation analysis. Three bacterial genera, namely, Gluconacetobacter, Lactobacillus, Lactococcus, and three fungal genera of Pichia, Wickerhamomyces, and Saccharomyces, were determined as the core functional microbiota for production of main volatile compounds in Wuyi Hong Qu glutinous rice wine. To conclude, information provided by this study is valuable to the development of effective strategies for the selection of beneficial bacterial and fungal strains to improve the quality of Wuyi Hong Qu glutinous rice wine.
Subject(s)
Bacteria/metabolism , Flavoring Agents/metabolism , Fungi/metabolism , Microbiota , Oryza/microbiology , Volatile Organic Compounds/metabolism , Wine/microbiology , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Biodiversity , China , Fermentation , Flavoring Agents/chemistry , Fungi/classification , Fungi/genetics , Fungi/isolation & purification , Oryza/chemistry , Volatile Organic Compounds/chemistry , Wine/analysisABSTRACT
Lactobacillus paracasei FZU103, a probiotic previously isolated from the traditional brewing process of Hongqu rice wine, may have the beneficial effect of improving the disorder of lipid metabolism. This study aimed to determine the beneficial effects of L. paracasei FZU103 on improving hepatic lipid accumulation associated with hyperlipidemia. Results indicated that L. paracasei FZU103 intervention significantly inhibited the abnormal growth of body weight and epididymal white adipose tissue (eWAT), prevented the hypertrophy of epididymal adipocytes, ameliorated the biochemical parameters of serum and liver related to lipid metabolism in HFD-fed mice. Histological analysis also showed that the excessive accumulation oflipid dropletsin the livers induced by HFD-feeding was greatly alleviated by L. paracasei FZU103 intervention. In addition, L. paracasei FZU103 also promoted the excretion of bile acids (BAs) through feces. Metagenomic analysis revealed that oral supplementation with L. paracasei FZU103 significantly increased the relative abundance of Ruminococcus, Alistipes, Pseudoflavonifractor and Helicobacter, but decreased the levels of Blautia, Staphylococcos and Tannerella in HFD-fed mice. The relationships between lipid metabolic parameters and intestinal microbial phylotypes were also revealed by correlation heatmap and network. Furthermore, ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS)-based liver metabolomics demonstrated that L. paracasei FZU103 had a significant regulatory effect on the metabolic pathways of glycerophospholipid metabolism, fatty acid degradation, fatty acid elongation, unsaturated fatty acids biosynthesis, riboflavin metabolism, glycerolipid metabolism, primary bile acid biosynthesis, arachidonic acid metabolism, etc. Additionally, L. paracasei FZU103 intervention regulated expression of hepatic genes involved in lipid metabolism and bile acid homeostasis, and promoted fecal excretion of intestinal BAs. These findings present new evidence supporting that L. paracasei FZU103 has the potential to improve lipid metabolism, and could be used as a potential functional food for the prevention of hyperlipidemia.
Subject(s)
Gastrointestinal Microbiome , Hyperlipidemias , Lacticaseibacillus paracasei , Animals , Diet, High-Fat , Hyperlipidemias/prevention & control , Lipid Metabolism , MiceABSTRACT
Ganoderic acid A (GA) is one of the most abundant triterpenoids in Ganoderma lucidum, and has been proved to possess a wide range of beneficial health effects. The aim of the current study is to investigate the amelioration effects and mechanism of GA on improving hyperlipidemia in mice fed a high-fat diet (HFD). The results showed that GA intervention significantly inhibited the abnormal growth of body weight and epididymal white adipose tissue (eWAT), prevented the hypertrophy of epididymal adipocytes, and ameliorated the biochemical parameters of serum and liver related to lipid metabolism in HFD-fed mice. Histological analysis also showed that the excessive accumulation of lipid droplets in the liver induced by HFD-feeding was greatly alleviated by GA intervention. In addition, GA intervention also increased the level of short chain fatty acids (SCFAs) in the intestine and promoted the excretion of bile acids (BAs) through feces. High-throughput sequencing of bacterial full-length 16S rDNA revealed that daily supplementation with GA made significant structural changes in the gut microbial population of mice fed with HFD, in particular modulating the relative abundance of some function related microbial phylotypes. The relationships between lipid metabolic parameters and gut microbial phylotypes were also revealed by correlation analysis based on a heatmap and network. The result showed that 46 key gut microbial phylotypes (OTUs) were markedly correlated with at least one lipid metabolic parameter. Moreover, UPLC-QTOF/MS-based liver metabolomics showed that 111 biomarkers (47 up-regulated metabolites and 64 down-regulated metabolites) were significantly changed after high-dose GA intervention (75 mg kg-1 day-1), compared with the HFD-fed hyperlipidemic mice. Metabolic pathway enrichment analysis of the differential hepatic metabolites demonstrated that GA intervention had significant regulatory effects on primary bile acid biosynthesis, fatty acid biosynthesis, amino sugar and nucleotide sugar metabolism, inositol phosphate metabolism, and so on. In addition, GA intervention regulated the mRNA levels of hepatic genes involved in fatty acid metabolism and bile acid homeostasis. These findings present new evidence supporting that GA from G. lucidum has the potential to alleviate lipid metabolic disorders and ameliorate the imbalance of gut microflora in a positive way.
Subject(s)
Gastrointestinal Microbiome/drug effects , Heptanoic Acids/pharmacology , Hyperlipidemias/therapy , Lanosterol/analogs & derivatives , Lipid Metabolism/drug effects , Reishi/chemistry , Animals , Bile Acids and Salts/metabolism , Diet, High-Fat/adverse effects , Disease Models, Animal , Fatty Acids, Volatile/metabolism , Feces/chemistry , Hyperlipidemias/etiology , Hyperlipidemias/metabolism , Lanosterol/pharmacology , Liver/metabolism , Male , Metabolomics , MiceABSTRACT
Monascus-fermented rice has been used to treat digestive disorder and promote blood circulation in China and other Asian countries for centuries. However, the effects and mechanisms of Monascus purpureus-fermented common buckwheat (HQ) on non-alcoholic fatty liver disease (NAFLD) and dyslipidemia are unclear. Here, oral supplementation of HQ significantly inhibited the abnormal growth of body weight and epididymal white adipose tissue (eWAT), prevented the hypertrophy of epididymal adipocytes, ameliorated some biochemical parameters of serum and liver related to lipid metabolism in mice fed a high-fat and high-cholesterol diet (HFD). Histological analysis also showed that the excessive accumulation of lipid droplets in the livers induced by HFD-feeding was greatly alleviated by HQ supplementation. Metagenomic analysis revealed that HQ supplementation made significant structural changes in the intestinal microflora of mice fed with HFD. The Spearman's correlation analysis revealed that physiological index, serum and liver lipid profiles were positively correlated with Bacteroidales S24-7, Streptococcus, Allobaculum, and Clostridiales XIII, but negatively associated with Lactobacillus, Ruminococcaceae_NK4A214 group, Ruminiclostridium, and Alistipes. UPLC-QTOF/MS-based liver metabolomics demonstrated that HQ intervention had significant regulatory effects on the metabolic pathways of primary bile acid biosynthesis, pyrimidine metabolism, ether lipid metabolism, glutathione metabolism, glycine, serine and threonine metabolism, and amino sugar and nucleotide sugar metabolism, etc. Additionally, HQ intervention regulated the mRNA levels of hepatic genes involved in hepatic lipid metabolism and bile acid homeostasis. Collectively, these findings present new evidence supporting that HQ has the potential to ameliorate dyslipidemia and NAFLD via modulating the intestinal microbial populations and hepatic metabolite profile in hyperlipidemic mice induced by HFD.
Subject(s)
Fagopyrum , Gastrointestinal Microbiome , Monascus , Non-alcoholic Fatty Liver Disease , Animals , Asia , China , Diet, High-Fat , Metabolome , Mice , Non-alcoholic Fatty Liver Disease/prevention & controlABSTRACT
This study aimed to investigate the protective mechanism of common buckwheat (Fagopyrum esculentum Moench.) against nonalcoholic fatty liver disease (NAFLD) associated with dyslipidemia in mice that were fed a high-fat and high-cholesterol diet (HFD). Results showed that oral supplementation of common buckwheat significantly improved physiological indexes and biochemical parameters related to dyslipidemia and NAFLD in mice fed with HFD. Furthermore, the HFD-induced reductions in fecal short-chain fatty acids were reversed by common buckwheat intervention, which also increased the fecal bile acid (BA) abundance compared with HFD-induced hyperlipidemic mice. Liver metabolomics based on ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry demonstrated that common buckwheat supplementation made significant regulatory effects on the pentose phosphate pathway, starch and sucrose metabolism, primary BA biosynthesis, and so forth. The results of high-throughput sequencing revealed that common buckwheat supplementation significantly altered the structure of the intestinal microbiota in mice fed with HFD. The correlations between lipid metabolic parameters and intestinal microbial phylotypes were also revealed by the heatmap and network. Additionally, common buckwheat intervention regulated the mRNA expressions of genes responsible for liver lipid metabolism and BA homeostasis, thus promoting BA synthesis and excretion. These findings confirmed that common buckwheat has the outstanding ability of improving lipid metabolism and could be used as a potential functional food for the prevention of NAFLD and hyperlipidemia.
Subject(s)
Cholesterol/metabolism , Fagopyrum/metabolism , Hyperlipidemias/diet therapy , Non-alcoholic Fatty Liver Disease/diet therapy , Animals , Bile Acids and Salts/metabolism , Cholesterol/adverse effects , Diet, High-Fat/adverse effects , Gastrointestinal Microbiome , Humans , Hyperlipidemias/etiology , Hyperlipidemias/metabolism , Hyperlipidemias/microbiology , Liver/metabolism , Male , Mice , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , Non-alcoholic Fatty Liver Disease/microbiologyABSTRACT
Polysaccharide from Grifola frondosa is an excellent metal-ion chelating agent owing to its distinctive structure and outstanding functional activities. Our previous research has successfully synthesized novel organic chromium derived from the chelation ofG. frondosapolysaccharide-chromium (III) [GFP-Cr(III)]. The purpose of present research was to reveal the hypoglycemic and hypolipidemic mechanism of GFP-Cr(III), and its relationship with the modulation of intestinal microflora. Successful fabrication of GFP-Cr(III) was verified by thermogravimetric analysis (TGA), powder X-ray diffraction (XRD) and 1H NMR spectrum.The hypoglycemic and hypolipidemic effects were examined using type 2 diabetic mice induced by a high-fat diet (HFD) and streptozocin (STZ). Results indicated that GFP-Cr(III) intervention improved abnormal serum biochemical indicators (triglyceride (TG), cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and glucose), inhibited lipid accumulation and steatosis in the liver. Metagenomic analysis revealed that GFP-Cr(III) treatment produced obvious changes on the intestinal microflora in T2DM mice. Thecorrelationnetwork analysis further revealed that the serum and hepatic lipid profiles were positively correlated with Streptococcus and Enterococcus, but negatively correlated with Enterorhabdus, Ruminococcaceae-UCG-011, Coriobacteriaceae and Micrococcaceae. Meanwhile, oral administration with GFP-Cr(III) regulated the mRNA expression related to glucose and lipid metabolism. These results of present study suggest that GFP-Cr(III) could be used as potential functional food ingredients for the amelioration of hyperglycemia and hyperlipidemia.
Subject(s)
Chelating Agents/pharmacology , Chromium/chemistry , Gastrointestinal Microbiome/drug effects , Grifola/chemistry , Hypoglycemic Agents/pharmacology , Hypolipidemic Agents/pharmacology , Polysaccharides/pharmacology , Streptozocin/pharmacology , Animals , Blood Glucose/metabolism , Cholesterol/blood , Diabetes Mellitus, Experimental , Diet, High-Fat/adverse effects , Dietary Carbohydrates/pharmacology , Glucose/metabolism , Hyperglycemia/metabolism , Lipid Metabolism/drug effects , Liver/drug effects , Liver/metabolism , Male , Metagenomics , Mice , RNA, Messenger/metabolism , Triglycerides/bloodABSTRACT
This study aimed to investigate the hypoglycemic and hypolipidemic activities of polysaccharides from Grifola frondosa (GFP) in diabetic mice induced by high-fat diet (HFD) and streptozotocin (STZ). Results showed that oral administration of GFP markedly reduced the serum levels of fasting blood glucose (FBG), oral glucose tolerance (OGT), cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C), and significantly decreased the hepatic levels of TC, TG and free fatty acids (FFA). Meanwhile, high-dose of GFP supplementation (900 mg/kg day) also showed powerful effects on moderating the composition of intestinal microflora in diabetic mice, especially altering the functionally relevant intestinal microbial phylotypes. Spearman's correlation network analysis revealed that key microbial phylotypes responding to GFP intervention were strongly correlated with the glucose and lipid metabolic disorders associated parameters. Moreover, GFP treatment regulated mRNA expression levels of the genes responsible for hepatic glucose and lipid metabolism. Itâ¯isâ¯noteworthyâ¯that GFP treatment markedly increased mRNA expression of cholesterol 7α-hydroxylase (CYP7A1) and bile salt export pump (BSEP), suggesting an enhancement of bile acids (BAs) synthesis and excretion in liver. These findings demonstrated that GFP could prevent hyperglycemia and hyperlipidemia in diabetic mice by altering gut microbiota and regulating hepatic glycolipid metabolism related genes, and therefore could be used as potential functional food ingredients for the prevention or treatment of hyperglycemia and hyperlipidemia.
Subject(s)
Diabetes Mellitus, Experimental/microbiology , Diet, High-Fat/adverse effects , Fungal Polysaccharides/pharmacology , Gastrointestinal Microbiome/drug effects , Grifola/chemistry , Hypoglycemic Agents/pharmacology , Hypolipidemic Agents/pharmacology , Animals , Body Weight/drug effects , Cecum/drug effects , Cecum/metabolism , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Fatty Acids, Volatile/metabolism , Glucose/metabolism , Lipid Metabolism/drug effects , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , MiceABSTRACT
The purpose of this study was to assess the potential effects of polysaccharides from edible mushroom Grifola frondosa (GFP) on lipid metabolic disorders and gut microbiota dysbiosis, and elucidate their possible regulatory mechanisms on lipid and cholesterol metabolism in high-fat diet (HFD)-exacerbated hyperlipidemic and hypercholesterolemic rats. Results showed that oral administration of GFP markedly alleviated dyslipidaemia through decreasing the serum levels of total triglycerides, total cholesterol, and free fatty acids, and significantly suppressing hepatic lipid accumulation and steatosis. Besides, the excretion of fecal bile acids was also promoted by oral administration of GFP. Metagenomic analysis revealed that GFP supplementation (400 mg kg-1 day-1) resulted in significant structure changes on gut microbiota in HFD-fed rats, in particular modulating the relative abundance of functionally relevant microbial phylotypes compared with the HFD group. Key microbial phylotypes responding to GFP intervention were identified to strongly correlate with the lipid metabolism disorder associated parameters using the correlation network based on Spearman's correlation coefficient. Serum and hepatic lipid profiles were found positively correlated with Clostridium-XVIII, Butyricicoccus and Turicibacter, but negatively correlated with Helicobater, Intestinimonas, Barnesiella, Parasutterella, Ruminococcus and Flavonifracter. Moreover, GFP treatment (400 mg kg-1 day-1) regulated the mRNA expression levels of the genes responsible for hepatic lipid and cholesterol metabolism. Oral supplementation of GFP markedly increased the mRNA expression of cholesterol 7α-hydroxylase (CYP7A1) and bile salt export pump (BSEP), suggesting an enhancement of bile acid (BA) synthesis and excretion from the liver. These findings illustrated that GFP could ameliorate lipid metabolic disorders through modulating specific gut microbial phylotypes and regulating hepatic lipid and cholesterol metabolism related genes, and therefore could be used as a potential functional food ingredient for the prevention or treatment of hyperlipidemia.
Subject(s)
Dysbiosis/drug therapy , Gastrointestinal Microbiome/drug effects , Grifola/chemistry , Lipid Metabolism Disorders/drug therapy , Plant Extracts/administration & dosage , Polysaccharides/administration & dosage , Animals , Bacteria/classification , Bacteria/drug effects , Bacteria/genetics , Bacteria/isolation & purification , Cholesterol/blood , Cholesterol 7-alpha-Hydroxylase/genetics , Cholesterol 7-alpha-Hydroxylase/metabolism , Diet, High-Fat/adverse effects , Dysbiosis/metabolism , Dysbiosis/microbiology , Fatty Acids, Nonesterified/blood , Humans , Lipid Metabolism/drug effects , Lipid Metabolism Disorders/genetics , Lipid Metabolism Disorders/metabolism , Lipid Metabolism Disorders/microbiology , Liver/drug effects , Liver/metabolism , Male , Rats , Rats, Wistar , Triglycerides/bloodABSTRACT
Hong Qu glutinous rice wine (HQGRW), as one of the most typical representatives of Chinese rice wine, is generally brewed from glutinous rice by adding two traditional wine fermentation starters-Hong Qu (HQ) and Bai Qu (BQ). The objective of this study was to determine the microbial communities and volatile metabolites of different traditional fermentation starters for HQGRW, and elucidate the potential correlation between microbiota and volatile metabolites. Both heatmap and principal component analysis (PCA) revealed the significant variances in volatile profiles among different wine starters. Microbiological analysis based on high-throughput sequencing (HTS) technology demonstrated that both of bacterial and fungal communities varied significantly in different starters. HQ was dominated mainly by bacteria of Bacillus ginsengihumi (20.17%), Pantoea sp. (10.39%), Elizabethkingia sp. (5.52%), Streptococcus sp. (5.03%) Brevundimonas sp. (3.03%), Rickettsia prowazekii (2.94%), Thermus thermophilus (2.54%), Bacillus amyloliquefaciens (1.48%), Bacillus aryabhattai (1.42%); fungi of Monascus purpureus (39.7%), Aspergillus niger (27.35%), Xeromyces bisporus (8.39%), Aspergillus penicillioides (6.89%), Aspergillus flavus (2.33%) and Pichia farinose (0.79%). By contrast, BQ contained much higher proportions of bacteria of Lactococcus lactis (10.45%), Lactobacillus brevis (9.99%), Pediococcus pentosaceus (8.29%), Weissella paramesenteroides (6.69%), Lactobacillus fermentum (4.83%), Gluconobacter thailandicus (3.93%), Lactobacillus alimentarius (3.59%), fungi of Rhizopus arrhizus (31.47%), Saccharomycopsis fibuligera (27.86%), Aspergillus niger (20.81%), Issatchenkia orientalis (3.79%), Saccharomycopsis malanga (3.15%), Clavispora lusitaniae (2.29%), Candida tropicalis (1.47%), Saccharomyces cerevisiae (1.11%) and Rhizopus microsporus (0.57%). Furthermore, core functional microbiota that might contribute to volatile flavour development was explored through Spearman's correlation-based network analysis. Lactobacillus brevis, Lactobacillus alimentarius, Lactobacillus plantarum and Aspergillus niger were found to be strongly associated with acid compounds (FDR adjusted Pâ¯<â¯0.01), while Pichia sp., Candida sp., Monascus purpureus, Lactobacillus brevis and Lactobacillus alimentarius were positively correlated with concentrations of aromatic esters associated with fruity and floral notes (FDR adjusted Pâ¯<â¯0.01), implying that these microorganisms might make significant contributions to the flavour of rice wine. These findings demonstrated that the aromatic quality of HQGRW may be critically influenced by the microbiota in traditional fermentation starters. To conclude, this study would contribute to the development of novel defined starter cultures for improving the aromatic quality of HQGRW.
Subject(s)
Fermentation , Microbiota , Oryza/metabolism , Volatile Organic Compounds/analysis , Wine/analysis , Wine/microbiology , Bacteria/classification , Bacteria/genetics , Bacteria/metabolism , Biodiversity , Fungi/classification , Fungi/genetics , Fungi/metabolism , High-Throughput Screening Assays , MycobiomeABSTRACT
Polysaccharide from Ganoderma lucidum is one of the best metal-ion chelating agents because of its structural characteristics and excellent functional activities. In this study, we synthesized and characterized a novel G. lucidum polysaccharidechromium (III) [GLP-Cr(III)] complex. Response surface methodology (RSM) was used to optimize the reaction conditions for the maximum chelation rate of GLP-Cr(III) complex. The optimal reaction conditions obtained from RSM were as follows: concentration of CrCl3 5.71â¯mg/mL, pHâ¯6.36, temperature 66.4⯰C and time 2.0â¯h, respectively. The pH was the most significant factor, followed by reaction temperature and CrCl3 concentration. Under the optimal conditions, the experimental chelation rate was 94.17⯱â¯1.0% for GLP-Cr(III) complex, which agreed closely with the predicted value (94.60%). Fourier transform infrared (FT-IR) spectroscopy revealed that the primary sites of chromium (III)-binding in G. lucidum polysaccharide were OH and CO groups, which induce the morphology change from flat sheet to rough surface. Meanwhile, according to the result of X-ray diffraction (XRD), the crystal degree of GLP was disappeared after chelation with Cr(III). The presence of a "blind zone" in the 1H NMR spectrum obviously indicated the binding of Cr(III) to GLP. Additionally, the effects of GLP-Cr(III) complex on hyperglycemia and hyperlipidemia in high fructose and fat diet-induced pre-diabetic mice were also investigated. Results showed that the serum total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), fasting blood glucose levels and glucose tolerance in mice supplemented with GLP-Cr(III) complex (50â¯mg/kgâ¯day) were significantly lower than the model group (Pâ¯<â¯0.01). More importantly, the GLP-Cr(III) complex had no significant adverse effects on the physiological metabolism, organ index, and liver tissue morphology of mice fed a normal diet. These results suggest that GLP-Cr(III) complex could be used as potential functional food ingredients for the prevention or treatment of hyperglycemia and hyperlipidemia.
Subject(s)
Basidiomycota/chemistry , Chromium/chemistry , Fungal Polysaccharides/chemistry , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , Hypolipidemic Agents/chemistry , Hypolipidemic Agents/pharmacology , Animals , Blood Glucose , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/etiology , Diet, High-Fat , Glucose Tolerance Test , Male , Mice , Spectrum AnalysisABSTRACT
Polysaccharide from Grifola frondosa is one of the best metal-ion chelating agents because of its structural characteristics and excellent functional activities. In this study, we synthesized and characterized a novel Grifola frondosa polysaccharide-chromium (III) [GFP-Cr(III)] complex. Response surface methodology (RSM) was used to optimize the reaction conditions for the maximum chelation rate of GFP-Cr(III) complex. The optimal reaction conditions obtained from RSM were as follows: concentration of CrCl3 6.97â¯mg/mL, pHâ¯7.75 and temperature 71.73⯰C, respectively. The pH was the most significant factor, followed by reaction temperature and concentration of CrCl3. Under the deduced optimal conditions (CrCl3 7.0â¯mg/mL, pHâ¯7.7 and temperature 70.0⯰C), the experimental chelation rate was 28.01%⯱â¯0.18% for GFP-Cr(III) complex, which agreed closely with the predicted value (27.61%). Fourier transform infrared (FTIR) spectroscopy revealed that the primary sites of chromium (III)-binding in polysaccharides were OH and CN groups, leading to the structure of GFP-Cr(III) complex was loose than the original polysaccharide. Nevertheless, Cr(III) did not make a fundamental change in the structure of GFP when comparing the FTIR spectra of GFP and GFP-Cr(III) complex. Additionally, the effects of GFP-Cr(III) complex on hyperglycemia and hyperlipidemia in high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic mice were also investigated. Results showed that the serum total cholesterol (TC), total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), fasting blood glucose levels and glucose tolerance in diabetic mice fed a high-fat diet (HFD) supplemented with GFP-Cr(III) complex (900â¯mg/kgâ¯day) were significantly lower than the diabetic group (Pâ¯<â¯0.01). These results suggest that GFP-Cr(III) complex could be used as potential functional food ingredients for the prevention or treatment of hyperglycemia and hyperlipidemia.
Subject(s)
Chromium/chemistry , Fungal Polysaccharides/chemistry , Grifola/chemistry , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , Hypolipidemic Agents/chemistry , Hypolipidemic Agents/pharmacology , Animals , Blood Glucose , Diabetes Mellitus, Experimental , Diet, High-Fat , Disease Models, Animal , Lipid Metabolism/drug effects , Liver/drug effects , Liver/metabolism , Male , Mice , Spectrum Analysis , Streptozocin/adverse effectsABSTRACT
The widespread occurrence of ethyl carbamate (EC, 89.09 Da), a group 2A carcinogen, in fermented foods and alcoholic beverages has raised worldwide public health concern. Immunoassay for EC is unavailable due to the simple and small structure of EC. In this work, an initial attempt to produce antibody specific for EC, by using 4-((ethoxycarbonyl)amino)butanoic acid as hapten, was made but failed. However, since EC can easily react with 9-xanthydrol to form xanthyl ethyl carbamate (XEC), two haptens based on XEC structure were designed and synthesized. Polyclonal antibody against XEC, instead of EC was obtained and then used to develop a competitive indirect ELISA for EC via a pre-analysis derivatization. After optimization, the ciELISA was applied in analyzing Chinese rice wine with detection limit of 166 µg/L, and negligible cross-reactivity with EC analogs. Recoveries of EC in fortified samples were from 84.4% to 100.9%, with coefficients of variation below 10%. Results for analysis of real samples by the ci-ELISA correlated well with that by reference method GC-MS, suggesting the good accuracy and reproducibility of the proposed method. This is the first report of an immunoassay capable of detecting EC, which is suitable for monitoring EC in a large amount of samples.