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Food Research International (Ottawa,... Oct 2021Oxygen involved fermentation is generally recognized as the critical process for the formation of quality of black tea. However, the specific role of oxygen plays in...
Oxygen involved fermentation is generally recognized as the critical process for the formation of quality of black tea. However, the specific role of oxygen plays in taste-related metabolites' alteration has not been illustrated clearly. In the present work, a series of fermentation systems with different oxygen concentrations were used to investigate the mechanism of the effects of oxygen on the quality and nonvolatile metabolites in black tea. The results showed that oxygen-enriched fermentation significantly improved the taste of black tea. And sixty-six metabolites, including catechins, theaflavins (TFs), proanthocyanidins, amino acids, flavonoid glycosides, and phenolic acids, were significantly different in the black teas fermented by three oxygen concentrations. Meanwhile, a 10-30% decrease in catechins, flavonoid glycosides and phenolic acids and a 5% increase in TFs, glutamate and glutamine in oxygen-enriched group, when compared to the control group, reduced astringency and bitterness and enhanced umami intensity. Furthermore, increased oxygen concentrations promoted the oxidation of catechins, flavonoid glycosides and some phenolic acids. And catechins oxidation in turn could accelerate the degradation of amino acids to form volatile aldehydes and also promote phenolic acids oxidation. Our results reveal the potential role of oxygen plays in the metabolites' alteration in black tea during fermentation, which gives a new insight into understanding the quality formation of black tea.
Topics: Astringents; Fermentation; Oxygen; Taste; Tea
PubMed: 34507757
DOI: 10.1016/j.foodres.2021.110613 -
Food Chemistry Jan 2023Astringency removal is important for the quality of Torreya grandis nut and occurs after harvest. Here, we evaluated the effect of NaHCO treatment on astringency removal...
Astringency removal is important for the quality of Torreya grandis nut and occurs after harvest. Here, we evaluated the effect of NaHCO treatment on astringency removal and compared the differential metabolites of the seed coat and kernel using a UHPLC QQQ-MS-based metabolomics approach. The result revealed the nut astringency was primarily enriched in the seed coat with more soluble tannins. The NaHCO treatment greatly shortened the de-astringency process, as indicated by a faster conversion of soluble tannins to insoluble tannins and more acetaldehyde production. Besides, a total of 293 metabolites, including 92 phenolic acids and 37 flavonoids, were tentatively characterized in the seed coat. A further comparative analysis of the metabolomics indicated epigallocatechin, gallocatechin, catechin, procyanidin B1, B2, B3 and C1 to be the major metabolites influenced by the NaHCO treatment. This study provides new insights regarding the metabolite differences of Torreya grandis nuts processed with different de-astringent treatments.
Topics: Astringents; Metabolomics; Nuts; Tannins; Taxaceae
PubMed: 35987001
DOI: 10.1016/j.foodchem.2022.133859 -
Journal of Agricultural and Food... Mar 2017The interaction of astringent substances with salivary proteins, which results in protein precipitation, is considered a key event in the molecular mechanism underlying...
The interaction of astringent substances with salivary proteins, which results in protein precipitation, is considered a key event in the molecular mechanism underlying the oral sensation of puckering astringency. As the chemical nature of orally active astringents is diverse and the knowledge of their interactions with salivary proteins rather fragmentary, human whole saliva samples were incubated with suprathreshold and isointensity solutions of the astringent polyphenol (-)-epigallocatechin gallate, the multivalent metal salt iron(III) sulfate, the amino-functionalized polysaccharide chitosan, and the basic protein lysozyme. After separation of the precipitated proteins, the proteins affected by the astringents were identified and relatively quantified for the first time by complementary bottom-up and top-down mass spectrometry-based proteomics approaches. Major salivary target proteins, which may be involved in astringency perception, are reported here for each astringent stimulus.
Topics: Adult; Astringents; Electrophoresis, Polyacrylamide Gel; Female; Humans; Male; Mass Spectrometry; Mouth; Proteomics; Salivary Proteins and Peptides; Taste; Young Adult
PubMed: 28225606
DOI: 10.1021/acs.jafc.7b00436 -
Colloids and Surfaces. B, Biointerfaces Feb 2019The proteinaceous pellicle layer, which develops upon contact with saliva on the surface of teeth, is important for the formation of oral biofilms and for the protection...
The proteinaceous pellicle layer, which develops upon contact with saliva on the surface of teeth, is important for the formation of oral biofilms and for the protection of teeth from abrasion and chemically induced erosion. Astringent food ingredients comprising polyphenols, cationic macromolecules, and multivalent metal salts are known to interact with the pellicle. However, astringent-induced changes in the physicochemical properties of the tooth-saliva interphase are not yet completely understood. Here we provide comprehensive insights into interfacial charging, ultrastructure, thickness, and surface roughness of the pellicles formed on the model substrates silicon oxide (SiO), Teflon AF, and hydroxyapatite, as well as on bovine enamel before and after incubation with the astringents epigallocatechin gallate, tannic acid, iron(III) salt, lysozyme, and chitosan. Quartz crystal microbalance with dissipation monitoring demonstrated viscous behavior of untreated pellicles formed in vitro on the different materials. Electrokinetic (streaming current) measurements revealed that cationic astringents reverse the charge of native pellicles, whereas polyphenols did not change the charge under physiological pH condition. In addition, transmission electron microscopy and atomic force microscopy showed a concentration-dependent increase in average film thickness and pellicle surface roughness as induced by astringents. These multifaceted alterations of the salivary pellicle may come along with an increase in roughness perceived on the teeth, which is part of the complex sensations of oral astringency.
Topics: Administration, Oral; Adult; Animals; Astringents; Cattle; Chitosan; Dental Enamel; Dental Pellicle; Ferric Compounds; Humans; Muramidase; Saliva; Salivary Proteins and Peptides; Silicon Dioxide; Surface Properties; Tooth
PubMed: 30497006
DOI: 10.1016/j.colsurfb.2018.11.028 -
Journal of Drugs in Dermatology : JDD Oct 2003Hyperhidrosis, or excessive sweating, is a disorder that may cause social isolation or occupational disability. It may be generalized or localized, and although... (Review)
Review
Hyperhidrosis, or excessive sweating, is a disorder that may cause social isolation or occupational disability. It may be generalized or localized, and although frequently idiopathic it may be a manifestation of a number of important systemic diseases. Drugs, surgical procedures, and electrical devices may all be employed by the physician as therapeutic weapons to treat hyperhidrosis.
Topics: Anti-Anxiety Agents; Anxiety; Astringents; Botulinum Toxins; Drug Administration Routes; Humans; Hyperhidrosis; Iontophoresis; Sweat Glands; Sweating
PubMed: 14558400
DOI: No ID Found -
Clinics in Dermatology 1988
Review
Topics: Anti-Infective Agents, Local; Astringents; Deodorants; Humans; Hyperhidrosis; Soaps
PubMed: 3071402
DOI: 10.1016/0738-081x(88)90030-2 -
Clinics in Dermatology 2001
Review
Topics: Astringents; Deodorants; Female; Humans; Male; Prognosis; Risk Assessment; Sensitivity and Specificity; Sweat Glands; Sweating
PubMed: 11535380
DOI: 10.1016/s0738-081x(01)00192-4 -
Current Problems in Dermatology 2002
Review
Topics: Administration, Cutaneous; Aluminum Chloride; Aluminum Compounds; Anesthetics, Local; Astringents; Chlorides; Cholinergic Antagonists; Deodorants; Dermatologic Agents; Humans; Hydrogen-Ion Concentration; Hyperhidrosis; Salts
PubMed: 12471696
DOI: 10.1159/000060693 -
Folia Biologica 2010The aim of this study was to evaluate the dynamics of the cytotoxicity of gingival margin retraction astringents based on aluminium chloride, aluminium sulphate, and...
The aim of this study was to evaluate the dynamics of the cytotoxicity of gingival margin retraction astringents based on aluminium chloride, aluminium sulphate, and ferric sulphate (solutions and gels) in human fibroblasts isolated from gingiva. The cytocompatibility of ten astringent-based chemical retraction agents: Gingiva Liquid, Alustin, Racestypine, Orbat sensitive, Astringedent®, Alustat, Hemostat, Racécord, Gel cord and ViscoStat®, in dilutions of 1 : 10 and 1 : 20, with human gingival fibroblasts was investigated. The MTT assay was performed to determine oxidoreductive mitochondrial function after 3, 5, 10 min and 24 h of incubation. Cell viability was determined according to the chemical group, concentration, exposure time, and the clinical form of the gingival retraction agents. Ferric sulphate- based agents were the most cytotoxic, followed by aluminium chloride and aluminium sulphate. The form of the astrigents influenced cell viability. The evaluated astringents may have cytotoxic potential for gingival margin tissues under clinical conditions.
Topics: Alum Compounds; Aluminum Chloride; Aluminum Compounds; Astringents; Cell Survival; Cells, Cultured; Chlorides; Coloring Agents; Ferric Compounds; Fibroblasts; Gingiva; Humans; Oxidation-Reduction; Tetrazolium Salts; Thiazoles
PubMed: 21324268
DOI: No ID Found -
Journal of Ethnopharmacology Feb 2024Rhubarb, a prominent traditional Chinese medicine, has been employed as a potent laxative for centuries and garnered particular popularity among the youth owing to its...
ETHNOPHARMACOLOGICAL RELEVANCE
Rhubarb, a prominent traditional Chinese medicine, has been employed as a potent laxative for centuries and garnered particular popularity among the youth owing to its notable efficacy in weight management. Historical records indicated that rhubarb initially exhibited robust laxative properties, but extended and consistent usage may lead to an astringent response in the later stage of long-term use. In contrast, steamed pieces of rhubarb (SR), preparing through the process of steaming with wine, have demonstrated a gentle laxative effect with no reported adverse effects.
AIM OF THE STUDY
Our study was designed to explore the intricate mechanisms underlying laxative and astringent properties of rhubarb through metabolomics research.
MATERIALS AND METHODS
In this investigation, we employed a serum metabolomics approach utilizing the UPLC-Q-Extractive-Orbitrap-MS method to delve into the contrasting laxative and astringent effects of rhubarb, as well as to unravel the mechanisms of underpinning its bidirectional regulatory influence. To commence, we assessed alterations in Evacuation Index (EI) values, intestinal hormone levels, and colon histopathology in mice to gauge rhubarb's laxative and astringent effects. Subsequently, metabolomics methodology was employed for cluster analysis through Principal Component Analysis (PCA) and biomarker identification via Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA). Then, we delved into the distinctions in characteristic biomarkers, metabolic pathways, their association with pathological changes, and correlation heatmap for biomarkers between raw pieces of rhubarb (RR) and SR to gain insights into the potential mechanisms behind rhubarb's bidirectional regulatory effects.
RESULTS
Our findings revealed that RR exhibited a laxative effect in the early stage and transitioned to an astringent effect in the later stage, as indicated by the EI values. In contrast, SR consistently demonstrated a mild laxative effect. Biochemical indexes and histopathological assessments unveiled that RR triggered its astringent effect by inhibiting secretion of motilin (MTL), promoting secretion of vasoactive intestinal peptide (VIP) and epinephrine (EPI), and inducing onset of inflammation. Furthermore, serum metabolomics analysis identified 59 discriminative biomarkers modulated by RR and SR. Through comprehensive analysis, we elucidated the in vivo transformation relationships among multiple endogenous metabolites. Notably, our results underscored the down-regulation of certain phosphatidylcholines (PCs), amino acids, acylcarnitines, and up-regulation of lysophosphatidylcholines (LysoPCs) played pivotal roles in the onset of gut dysfunction, intestinal inflammation, gut barrier damage, and gastrointestinal motility disorder upon prolonging RR administration, ultimately contributing to its astringent effect. Additionally, our correlation analysis elucidated that anthraquinones, stilbenes, and phenylbutanones were the pharmacodynamic material basis responsible for inducing the astringent effect of RR.
CONCLUSION
This study provides valuable insights into the bidirectional regulatory effects of rhubarb and sheds light on its underlying mechanisms through a comprehensive metabolomics approach.
Topics: Mice; Animals; Laxatives; Astringents; Rheum; Metabolomics; Inflammation; Biomarkers
PubMed: 37944871
DOI: 10.1016/j.jep.2023.117348