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Sonali Ray

Bio: Sonali Ray is an academic researcher from University of Calcutta. The author has contributed to research in topics: Epigallocatechin gallate & Gallic acid. The author has an hindex of 4, co-authored 4 publications receiving 36 citations.

Papers
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Journal Article
TL;DR: It has been found that 8-c-ascorbyl-(-)-epigallocatechin, rutin and orientin could be the putative molecules for amelioration of post-prandial hyperglycaemia whereas 8- c-asc or byl epigallocatedchin 3-o-gallate and schaftoside could be used to reduce fat absorption in obese persons.
Abstract: Black tea is one of the most widely consumed beverages in the world and traditionally known for its antidiabetic and antiobese property. However, the underlying mechanisms of these properties are not studied widely. In this work, we hypothesize that the reason could be because of the inhibition of gut enzymes by the tea derived phytochemicals. Molecular docking was used to explore the efficacy of tea components to inhibit the key enzymes related with Type II diabetes and obesity; α-glucosidase, α-amylase and lipase. Autodock4.2 molecular docking software that applies Lamarckian Genetic Algorithm was used. The ligand structures were retrieved from PubChem and KNApSAcK-3D database. PreADMET web server was used for Toxicity and ADME predictions. Based on this analysis, it has been found that 8-c-ascorbyl-(-)-epigallocatechin, rutin and orientin could be the putative molecules for amelioration of post-prandial hyperglycaemia whereas 8-c-ascorbyl-(-)-epigallocatechin, 8-c-ascorbyl epigallocatechin 3-o-gallate and schaftoside could be used to reduce fat absorption in obese persons. It can be concluded that these phytochemicals or their derivatives can be used for further in-vitro and in-vivo studies to design valuable drugs.

18 citations

Journal ArticleDOI
TL;DR: This in vitro study reveals that BT extract and the phenolic components may have potential benefit for controlling liver disorders, obesity and diabetes.
Abstract: The objective of the present study was to determine the inhibitory properties of the infusions and decoctions of four samples of Indian black tea (BT) and some of the tea flavonoids, gallic acid and caffeine, in vitro, against β- glucuronidase, lipase,α-amylase and α-glucosidase. These enzymes are related to liver disorders, obesity and diabetes. The phenolic constituents and caffeine content in the BT extracts were measured quantitatively by HPLC. It was noted that both infusion and decoction of BT had β-glucuronidase inhibitory property close to that of silymarin. Epigallocatechin gallate, epicatechin, and gallocatechin showed higher β-glucuronidase inhibitory activity than that of BT extracts and silymarin. BT extracts also inhibited the enzyme lipase. Thearubigin, theaflavin, epigallocatechin gallate, epicatechin and gallocatechin showed significant lipase inhibitory properties that were superior to the drug orlistat. The tea extracts, flavonoids and gallic acid inhibited the activity of α-amylase and α-glucosidase. Theaflavin and catechin had α-amylase inhibitory activity better than that of acarbose. This in vitro study reveals that BT extract and the phenolic components may have potential benefit for controlling liver disorders, obesity and diabetes.

7 citations

Journal ArticleDOI
TL;DR: In this paper, the authors compared chemical composition and angiotensin I-converting enzyme inhibitory properties of infusion and decoction of four samples of black tea and found that both infusion anddecoction inhibited the enzyme.
Abstract: Angiotensin I-converting enzyme inhibitors are used as therapeutic agents for the treatment of hypertension. Regular consumption of black tea (Camellia sinensis (L.) Kuntze, Theaceae) has been reported to lower blood pressure. The aims of the present work were to compare chemical composition and angiotensin I-converting enzyme inhibitory properties of infusion and decoction of four samples of black tea. GC/MS based metabolomics approach helped in identification of fifty-one metabolites including ten organic acids, one inorganic acid, sixteen amino acids, two sugars, five sugar alcohols, fifteen phenols and flavonoids, two fatty acids from infusions and decoctions of four black tea samples. Partial least squares discriminant analysis and orthogonal partial least squares discriminant analysis models showed good classification among the two groups, diffusion and infusion, based on metabolites. Both infusion and decoction inhibited the enzyme. However, the activity differed with samples. Multivariate analysis also segregated extracts on the basis of activity. Thearubigin, theaflavin, catechin inhibited the enzyme. Epicatechin, epigallocatechin gallate, gallic acid, caffeine showed lower activity.

6 citations

Peer Review
TL;DR: The objective of this review is to summarize all the available information on different bioactive components of tea in the treatment of different neurodegenerative diseases.
Abstract: Neurodegenerative diseases involve a heterogeneous group of disorders characterized by progressive impairment and degeneration of nerve structure and function, eventually leading towards the death of certain parts of the CNS and brain. The most common form of neurodegenerative diseases includes Alzheimer’s disease (AD) leading towards progressive loss of memory, Parkinson’s disease (PD) causing impairment in movements, Huntington’s disease (HD) affecting the ability to walk, talk and think. The pathogenesis of these diseases mainly AD and PD are complex and there is no such cure for these diseases as the drugs that are currently in use shown to have an adverse effect on these diseases. However epidemiological studies have shown that consumption of tea has therapeutic effects in treating those neurodegenerative diseases especially the major tea components i.e. Catechins, Caffeine, Theanine, TFs in elderly persons. The major tea components are antioxidants which help to combat oxidative stress, the major reason behind all those neurodegenerative diseases, regulating signaling pathways as well as helps in metal chelation. The objective of this review is to summarize all the available information on different bioactive components of tea in the treatment of different neurodegenerative diseases.

Cited by
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Journal Article
TL;DR: In this paper, the effect of apple polyphenol extract (AP) and procyanidin contained in AP on in vitro pancreatic lipase activity and in vivo triglyceride absorption in mice and humans were examined.
Abstract: Inhibitory effects of apple polyphenol extract (AP) and procyanidin contained in AP on in vitro pancreatic lipase activity and in vivo triglyceride absorption in mice and humans were examined. AP and procyanidin considerably inhibited in vitro pancreatic lipase activity. However, polyphenols, except for procyanidin, in AP (i.e., catechins, chalcones, and phenol carboxylic acids) showed weak inhibitory activities on pancreatic lipase. Procyanidins separated by normal-phase chromatography according to the degree of polymerization were also examined. Inhibitory effects of procyanidins increased according to the degree of polymerization from dimer to pentamer. On the other hand, pentamer or greater procyanidins showed maximal inhibitory effects on pancreatic lipase. These results suggested that with respect to in vitro pancreatic lipase inhibition, the degree of polymerization was an important factor and oligomeric procyanidin mainly contributed. Next, we performed a triglyceride tolerance test in mice and humans. Simultaneous ingestion of AP and triglyceride significantly inhibited an increase of plasma triglyceride levels in both models. These results suggested that the oligomeric procyanidins contained in AP inhibited triglyceride absorption by inhibiting pancreatic lipase activity in mice and humans.

44 citations

Journal ArticleDOI
TL;DR: The strong inhibition of PT on PL in the gastrointestinal tract might be one mechanism for its lipid-lowering effect.
Abstract: Pancreatic lipase (PL) is a critical enzyme associated with hyperlipidemia and obesity. A previous study of ours suggested that persimmon tannin (PT) was the main component accounting for the antihyperlipidemic effects of persimmon fruits, but the underlying mechanisms were unclear. In this present study, the inhibitory effect of PT on PL was studied and the possible mechanisms were evaluated by fluorescence spectroscopy, circular dichroism (CD) spectra, isothermal titration calorimetry (ITC), and molecular docking. PT had a high affinity to PL and inhibited the activity of PL with the half maximal inhibitory concertation (IC50) value of 0.44 mg/mL in a noncompetitive way. Furthermore, molecular docking revealed that the hydrogen bonding and π–π stacking was mainly responsible for the interaction. The strong inhibition of PT on PL in the gastrointestinal tract might be one mechanism for its lipid-lowering effect.

38 citations

Journal ArticleDOI
TL;DR: Qualitative analysis showed that amino acids and flavonoids might be responsible for the anti-obesity and anti-hyperglycemic effects of QZT.
Abstract: Qingzhuan tea (QZT), a post-fermented tea, has been reported to have anti-obesity and anti-hyperglycemic effects, perhaps due to bioactive compounds that inhibit lipase and α-amylase. It is unknown what chemical constituents' changes and what bioactive compounds occur during the manufacture of QZT. The aim of this study was to determine the secondary metabolites changes that occur during post-fermentation and how these changes affect the ability of QZT to inhibit the activities of lipase and α-amylase. During the processing steps, metabolites levels and their inhibitory effects on lipase and α-amylase were assessed. Changes in content and activities suggested that the first turn over or the second turn over was critical for the formation and conversion of bioactive compounds responsible for the anti-obesity and hypoglycemic effects. The relationship between constituents and activities was further evaluated by correlation analysis, which showed that amino acids and flavonoids might be responsible for the anti-obesity and anti-hyperglycemic effects of QZT. This study clarified that compounds were altered during pile fermentation of QZT and tentatively identified the bioactive compounds formed during QZT manufacture.

31 citations

Journal ArticleDOI
TL;DR: The present experiment reports the importance of both primary and secondary metabolites for the bioactivity of plant extracts and identifies the inhibitors of α-amylase and α-glucosidase using metabolomics and chemometric approaches.
Abstract: Achras sapota L. fruit extracts have previously been reported to have activities against the carbohydrate-digesting enzymes α-amylase and α-glucosidase. The present work was aimed to identify the inhibitors of α-amylase and α-glucosidase using metabolomics and chemometric approaches. Metabolite profile of Achras sapota fruit extracts at different stages of post-harvest ripening was analyzed using GC–MS-based metabolomics approach. The extracts were also assayed for their properties to inhibit the carbohydrate-digesting enzymes α-amylase and α-glucosidase in vitro. The fruit extracts just after harvesting showed maximum activities against the enzymes α-amylase and α-glucosidase. The activities declined with post-harvest ripening. It was observed from the chemometric analysis that gallic acid, chlorogenic acid, benzene-1,2,4-triol, and d-malic acid are responsible for high α-amylase inhibitory activity. Gallic acid and chlorogenic acid are positively correlated with high α-glucosidase inhibitory activity. Inhibition of the two enzymes by gallic acid, benzene-1,2,4-triol, chlorogenic acid, and α-amylase by d-malic acid supported the findings. The present experiment reports the importance of both primary and secondary metabolites for the bioactivity of plant extracts.

26 citations

Journal ArticleDOI
24 Dec 2020-Foods
TL;DR: A review of the most recent literature regarding the discovery of secondary metabolites through isolation and structural elucidation, as well as the in vitro and/or in vivo evaluation of their biological effects is discussed in this article.
Abstract: Secondary metabolites from plants and fungi are stimulating growing interest in consumers and, consequently, in the food and supplement industries. The beneficial effects of these natural compounds are being thoroughly studied and there are frequent updates about the biological activities of old and new molecules isolated from plants and fungi. In this article, we present a review of the most recent literature regarding the recent discovery of secondary metabolites through isolation and structural elucidation, as well as the in vitro and/or in vivo evaluation of their biological effects. In particular, the possibility of using these bioactive molecules in the prevention and/or treatment of widely spread pathologies such as cardiovascular and neurodegenerative diseases is discussed.

23 citations