Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
676
result(s) for
"Astringents"
Sort by:
Identification of UDP-glycosyltransferases involved in the biosynthesis of astringent taste compounds in tea (Camellia sinensis)
2016
Galloylated catechins and flavonol 3-O-glycosides are characteristic astringent taste compounds in tea (Camellia sinensis). The mechanism involved in the formation of these metabolites remains unknown in tea plants. In this paper, 178 UGT genes (CsUGTs) were identified in C. sinensis based on an analysis of tea transcriptome data. Phylogenetic analysis revealed that 132 of these genes were clustered into 15 previously established phylogenetic groups (A to M, O and P) and a newly identified group R. Three of the 11 recombinant UGT proteins tested were found to be involved in the in vitro biosynthesis of β-glucogallin and glycosylated flavonols. CsUGT84A22 exhibited catalytic activity toward phenolic acids, in particular gallic acid, to produce β-glucogallin, which is the immediate precursor of galloylated catechin biosynthesis in tea plants. CsUGT78A14 and CsUGT78A15 were found to be responsible for the biosynthesis of flavonol 3-O-glucosides and flavonol 3-O-galactosides, respectively. Site-directed mutagenesis of the Q373H substitution for CsUGT78A14 indicated that the Q (Gln) residue played a catalytically crucial role for flavonoid 3-O-glucosyltransferase activity. The expression profiles of the CsUGT84A22, CsUGT78A14, and CsUGT78A15 genes were correlated with the accumulation patterns of β-glucogallin and the glycosylated flavonols which indicated that these three CsUGT genes were involved in the biosynthesis of astringent compounds in C. sinensis.
Journal Article
Tannins in Food: Insights into the Molecular Perception of Astringency and Bitter Taste
by
Brandão, Elsa
,
de Freitas, Victor
,
Soares, Susana
in
Acids
,
Astringents - analysis
,
bitter taste receptors
2020
Astringency and bitterness are organoleptic properties widely linked to tannin compounds. Due to their significance to food chemistry, the food industry, and to human nutrition and health, these tannins’ taste properties have been a line of worldwide research. In recent years, significant advances have been made in understanding the molecular perception of astringency pointing to the contribution of different oral key players. Regarding bitterness, several polyphenols have been identified has new agonists of these receptors. This review summarizes the last data about the knowledge of these taste properties perceived by tannins. Ultimately, tannins’ astringency and bitterness are hand-in-hand taste properties, and future studies should be adapted to understand how the proper perception of one taste could affect the perception of the other one.
Journal Article
Investigating the influence of astringent compounds on oral lubrication and the protective role of proline-rich proteins
by
Pailler-Mattéi, Cyril
,
Ammam, Ianis
,
Ouillon, Lucas
in
631/61/54/994
,
639/166/988
,
Astringents
2025
Astringency, characterized by dryness and roughness in the mouth, is a major challenge for the acceptance of plant-based protein-rich foods. The mechanisms behind this sensation, particularly the role of mucins and the oral epithelium, remain unclear. This study investigates the impact of tannins, specifically epigallocatechin gallate (EgCG), on oral lubrication and examines the role of MUC1 protein in the lubrification and potentially in the astringency perception. The protective effect of proline-rich proteins (PRPs) is also explored. In vitro tribological tests were performed on four oral epithelial models expressing different MUC1 isoforms, using a reconstructed mucosal pellicle. A homemade biotribometer measured friction and dissipated energy to assess tannin-mucin interactions. Results confirm that EgCG disrupts epithelial lubrication, increasing frictional forces. However, MUC1 expression, particularly its structure, reduces these effects by preventing tannin aggregation and preserving lubrication. PRPs also enhance lubrication by binding tannins, limiting their interaction with mucins. This study highlights the roles of MUC1 and PRPs in oral lubrication in the presence of tannins.
Journal Article
Crossover Analysis of the Astringent, Antimicrobial, and Anti-inflammatory Effects of Illicium verum/Star Anise in the Oral Cavity
by
Assiry, Ali A.
,
Bhavikatti, Shaeesta Khaleelahmed
,
Marya, Anand
in
Adolescent
,
Adult
,
Age Factors
2021
Introduction. Illicium verum commonly known as star anise has been widely used in many Asian countries for pharmaceutical treatment for many diseases. The aim of the present study was to investigate the anti-inflammatory, astringent, and antimicrobial properties of an Illicium verum mouthwash. Methods. The present double blinded randomized clinical trial was conducted on fifty subjects, divided into groups A and B. Illicium verum mouthwash (group A) and placebo (group B) were provided to subjects for 21 days; after 14 days, washout period mouthwashes were switched as per crossover design between groups for 21 days. The gingival index (GI), papillary bleeding index (PBI), and oral microbial count were recorded at each stage of study. Results. The significant intragroup difference was observed, before crossover in group A and after crossover in group B for GI, PBI, and oral microbial count at different stages of study. On comparing both group A and group B at the first and second follow-up for GI, PBI, and oral microbial count, a statistically significant difference (p<0.05) was observed. A statistically highly significant mean intergroup and intragroup difference was seen for all the clinical parameters at different stages of study. Conclusion. The study revealed that the Illicium verum/star anise has potent antibacterial, anti-inflammatory, and astringent properties.
Journal Article
(Poly)phenols of apples contribute to in vitro antidiabetic properties: Assessment of Canada's Apple Biodiversity Collection
by
Migicovsky, Zoë
,
Yu, Cindy H. J.
,
Song, Jun
in
Acids
,
advanced glycation end products
,
Advanced glycosylation end products
2023
Societal Impact Statement Apples are affordable and accessible fruit with tremendous biodiversity. Among over 10,000 identified apple cultivars, only a few are commercially available. Habitual fruit consumption is correlated with the prevention of Type 2 diabetes and related complications. Particularly, (poly)phenols found in apples are major contributors to their antidiabetic properties. Here, we have screened (poly)phenol‐rich extracts of 476 apple accessions in Canada's Apple Biodiversity Collection for antidiabetic properties. The results of this work provide insights into the prevention and management of Type 2 diabetes by identifying high (poly)phenol‐containing specialty apples for use in fresh fruit form or value‐added functional food ingredients. Summary The recent trend in sedentary lifestyles and nutritionally‐imbalanced diets has elevated the prevalence of Type 2 diabetes in many parts of the world. Some pharmacological glycemic management can cause undesirable gastrointestinal side effects or hypoglycemia. Thus, there is a growing interest in safe glycemic management using dietary (poly)phenols. In this study, (poly)phenol‐rich extracts of 476 apple accessions from Canada's Apple Biodiversity Collection (ABC) and six major apple (poly)phenols were assessed for in vitro antidiabetic properties against the activities of α‐glucosidase, α‐amylase, and dipeptidyl peptidase‐4 (DPP‐4) and the formation of advanced glycation end products (AGE). Apple (poly)phenol extracts varied in their antidiabetic activities in a dose‐dependent manner. High (poly)phenol‐containing apples demonstrated that their total phenolic contents (TPC) were inversely correlated with the IC50 values of α‐glucosidase, α‐amylase, and AGE formation, but not DPP‐4. Concentrations of major (poly)phenol compounds such as procyanidin B2, phloridzin, and epicatechin in apples were significantly inversely correlated with IC50 values of α‐glucosidase in the high (poly)phenol‐containing apples. High TPC apples are not suitable for marketing for fresh fruit consumption due to bitterness and astringency; however, these apples show potential to use in the development of value‐added functional food ingredients or nutraceuticals for blood glucose management. The high TPC apple, “S23‐03‐749,” an advanced breeding line of dessert apple, presents a novel option as a specialty apple cultivar for the dietary management of glycemia. Summary Les pommes sont des fruits abordables et accessibles avec une formidable biodiversité. Parmi plus de 10,000 cultivars de pommiers identifiés, seuls quelques‐uns sont disponibles dans le commerce. La consommation habituelle de fruits est corrélée à la prévention du diabète de type 2 et des complications associées. En particulier, les (poly)phénols présents dans les pommes sont des contributeurs majeurs à leurs propriétés antidiabétiques. Ici, nous avons examiné des extraits riches en (poly)phénols de 476 pommes de la Collection Biodiversité des pommes du Canada pour leurs propriétés antidiabétiques. Les résultats de ces travaux donnent un aperçu de la prévention et de la gestion du diabète de type 2 en identifiant des pommes de spécialité à haute teneur en (poly)phénols à utiliser sous forme de fruits frais ou d'ingrédients alimentaires fonctionnels à valeur ajoutée. Apples are affordable and accessible fruit with tremendous biodiversity. Among over 10,000 identified apple cultivars, only a few are commercially available. Habitual fruit consumption is correlated with the prevention of Type 2 diabetes and related complications. Particularly, (poly)phenols found in apples are major contributors to their antidiabetic properties. Here, we have screened (poly)phenol‐rich extracts of 476 apple accessions in Canada's Apple Biodiversity Collection for antidiabetic properties. The results of this work provide insights into the prevention and management of Type 2 diabetes by identifying high (poly)phenol‐containing specialty apples for use in fresh fruit form or value‐added functional food ingredients.
Journal Article
A Scalable Bacterial Cellulose Ionogel for Multisensory Electronic Skin
2022
Electronic skin (e-skin), a new generation of flexible electronics, has drawn interest in soft robotics, artificial intelligence, and biomedical devices. However, most existing e-skins involve complex preparation procedures and are characterized by single-sensing capability and insufficient scalability. Here, we report on a one-step strategy in which a thermionic source is used for the in situ molecularization of bacterial cellulose polymeric fibers into molecular chains, controllably constructing an ionogel with a scalable mode for e-skin. The synergistic effect of a molecular-scale hydrogen bond interweaving network and a nanoscale fiber skeleton confers a robust tensile strength (up to 7.8 MPa) and high ionic conductivity (up to 62.58 mS/cm) on the as-developed ionogel. Inspired by the tongue to engineer the perceptual patterns in this ionogel, we present a smart e-skin with the perfect combination of excellent ion transport and discriminability, showing six stimulating responses to pressure, touch, temperature, humidity, magnetic force, and even astringency. This study proposes a simple, efficient, controllable, and sustainable approach toward a low-carbon, versatile, and scalable e-skin design and structure-performance development.
Journal Article
Zinc Supplementation in Treatment of Children With Urinary Tract Infection
by
Tabaei, Aram
,
Kahbazi, Manijeh
,
Taherahmadi, Hassan
in
Urinary tract diseases
,
Urinary tract infections
,
Urogenital system
2016
Introduction. Urinary tract infection (UTI) is very common in children. Precocious diagnosis and appropriate treatment are important because of the permanent disease complications. Zinc increases the response to treatment in many infections. In this study, we explored the effect of zinc in treating UTI.Materials and Methods. Two hundred children with UTI were divided into 2 groups of 100 who were comparable in terms of age, sex, urine laboratory profiles, and clinical signs and symptoms. The control group received a standard treatment protocol for UTI and the intervention group received oral zinc sulfate syrup plus routine treatment of UTI.Results. A faster recovery was observed in the patients receiving zinc, but abdominal pain was exacerbated by zinc and lasted longer. Three months after the treatment, there was no significant difference between the two groups in the time of fever stop and negative urine culture.Conclusions. In children with UTI, zinc supplementation has a positive effect in ameliorating severe dysuria and urinary frequency while the use of this medication is not recommended in the presence of abdominal pain.
Journal Article
Non-Volatile Compounds Involved in Bitterness and Astringency of Pulses: A Review
by
Karolkowski, Adeline
,
Salles, Christian
,
Belloir, Christine
in
Amino acids
,
astringency
,
Astringents
2023
Despite the many advantages of pulses, they are characterised by off-flavours that limit their consumption. Off-notes, bitterness and astringency contribute to negative perceptions of pulses. Several hypotheses have assumed that non-volatile compounds, including saponins, phenolic compounds, and alkaloids, are responsible for pulse bitterness and astringency. This review aims to provide an overview highlighting the non-volatile compounds identified in pulses and their bitter and/or astringent characteristics to suggest their potential involvement in pulse off-flavours. Sensorial analyses are mainly used to describe the bitterness and astringency of molecules. However, in vitro cellular assays have shown the activation of bitter taste receptors by many phenolic compounds, suggesting their potential involvement in pulse bitterness. A better knowledge of the non-volatile compounds involved in the off-flavours should enable the creation of efficient strategies to limit their impact on overall perception and increase consumer acceptability.
Journal Article
Ethylene-responsive transcription factors interact with promoters of ADH and PDC involved in persimmon (Diospyros kaki) fruit de-astringency
by
Yin, Xue-ren
,
Shi, Yan-na
,
Chen, Kun-song
in
acetaldehyde
,
alcohol dehydrogenase
,
Alcohol Dehydrogenase - genetics
2012
The persimmon fruit is a particularly good model for studying fruit response to hypoxia, in particular, the hypoxia-response ERF (HRE) genes. An anaerobic environment reduces fruit astringency by converting soluble condensed tannins (SCTs) into an insoluble form. Although the physiology of de-astringency has been widely studied, its molecular control is poorly understood. Both CO(2) and ethylene treatments efficiently removed the astringency from 'Mopan' persimmon fruit, as indicated by a decrease in SCTs. Acetaldehyde, the putative agent for causing de-astringency, accumulated during these treatments, as did activities of the key enzymes of acetaldehyde synthesis, alcohol dehydrogenase (ADH), and pyruvate decarboxylase (PDC). Eight DkADH and DkPDC genes were isolated, and three candidates for a role in de-astringency, DkADH1, DkPDC1, and DkPDC2, were characterized by transcriptional analysis in different tissues. The significance of these specific isoforms was confirmed by principal component analysis. Transient expression in leaf tissue showed that DkPDC2 decreased SCTs. Interactions of six hypoxia-responsive ERF genes and target promoters were tested in transient assays. The results indicated that two hypoxia-responsive ERF genes, DkERF9 and DkERF10, were involved in separately regulating the DkPDC2 and DkADH1 promoters. It is proposed that a DkERF-DkADH/DkPDC cascade is involved in regulating persimmon de-astringency.
Journal Article
Chemical affinity between tannin size and salivary protein binding abilities: implications for wine astringency
2016
Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs), belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP). However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly attributed to the lack of efficient strategies to isolate the PAs in non-galloylated forms and with individual degree size from grape/ wine. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5) was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified by an approach of preparative hydrophilic interaction chromatography. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed.
Journal Article