Compounds Catechin Research Articles

Selective Electrochemical Detection of Catechin Compounds in Herbal Medicines

Most electrochemical sensors reported for catechin determination in herbal medicines actually involve the detection of not only catechins but also other flavonoids. This work proposes a strategy to selectively detect and quantify flavan-3-ol, known as catechins, in the presence of other flavonoids by complexation with AlCl3. Flavonoids (e.g., rutin, quercetin) form stable complex with AlCl3 which affect the electrooxidation of these molecules. Hence, the electrochemical oxidation of catechin is free from the interference of other flavonoids as shown by differential-pulse voltammetry using glassy-carbon electrode. The approach was applied to herbal medicines and mass-spectrometry confirmed the presence of catechins in such samples.

Dissolution Study on Grape Polyphenol Hard Gelatin Capsule Dietary Supplements.

Methods for a dissolution study by ultra-high performance liquid chromatography/triple quadrupole mass spectrometry (UHPLC-QqQ/MS) analysis of grape polyphenol dietary supplements, namely, grape seed extract (GSE) and resveratrol (RSV) capsules, were developed following the guidance of United States Pharmacopeia (USP) <2040>. Two dissolution media, 0.1 N hydrochloric acid (pH 1.2) and 0.05 M acetate buffer (pH 4.6), were evaluated with dissolution apparatus (USP 1), 100 rpm rotation speed, and 900 ml dissolution medium volume. Dissolution profiling was performed over 120 min. Major phenolic compounds of gallic acid, catechin, epicatechin, and procyanidin B2 were quantitated to obtain the dissolution profile of GSE capsules, and trans-RSV was used for RSV capsules. Results indicated that the released trans-RSV for RSV capsules in both of the dissolution media meets the USP standards, and that for the GSE capsules, all the four marker compounds passed the dissolution test in the HCl medium but did not reach a 75% release within 60 min in the acetate buffer. These promising results suggest that the general USP dissolution protocols are adequate for the successful release of RSV capsules in HCl medium and acetate buffer and GSE capsules (in HCl medium), but may be inadequate for GSE capsules in acetate buffer. These results showed that under a low pH of 1.2 (simulated stomach environment), bioactive compounds were released on time from the GSE capsules and met the USP guidelines; however, under a higher pH of 4.6 (simulated duodenum environment), the same biomarkers failed, suggesting the need to further improve the dissolution of GSE over a wider range of pH environments to enhance bioavailability and efficacy.

Identification of Polyphenolics from Loranthus globosus as Potential Inhibitors of Cholinesterase and Oxidative Stress for Alzheimer's Disease Treatment.

Mistletoes are considered to be the potential medicinal herbs due to their rich traditional uses. Loranthus globosus is a Bangladeshi mango mistletoe that has been reported as folk medicine for various ailments and diseases. In an attempt to explore its effectiveness in Alzheimer's disease (AD), we investigated the antioxidant and acetylcholinesterase inhibitory activity of L. globosus. We report that the crude methanol extract (CME) of the plant contains a good amount of polyphenolics and possesses antioxidant and cholinesterase inhibitory activity. Fractionation of CME with solvents of varying polarity revealed the highest activity and polyphenolic content in the ethylacetate fraction (EAF). Correlation analysis revealed a significant (P < 0.05) association of polyphenolics with the antioxidant and cholinesterase inhibitory properties. Using column chromatography with diaion resin, the polyphenolics (EAF-PP) were isolated from the EAF that displayed the potent antioxidant and cholinesterase inhibitory activities. Kinetic analysis showed that EAF-PP exhibited a competitive type of inhibition. A total of thirty-six compounds including catechin and its different derivatives were identified in the EAF-PP by LC/MS analysis. Bioactivity-guided separation approach afforded the isolation of the two major active compounds catechin and catechin dimer from the EAF-PP. Hence, EAF-PP represents a potential source of antioxidants and cholinesterase inhibitors, which can be used in the management of AD.

(+)-Catechin, epicatechin and epigallocatechin gallate are important inducible defensive compounds against Ectropis grisescens in tea plants.

The tea plant, Camellia sinensis (L.) O. Kuntze, is an economically important, perennial woody plant rich in catechins. Although catechins have been reported to play an important role in plant defences against microbes, their roles in the defence of tea plants against herbivores remain unknown. In this study, we allowed the larvae of Ectropis grisescens, a leaf-feeding pest, to feed on the plants, and alternatively, we wounded the plants and then treated them with E. grisescens oral secretions (WOS). Both approaches triggered jasmonic acid-, ethylene- and auxin-mediated signalling pathways; as a result, plants accumulated three catechin compounds: (+)-catechin, epicatechin and epigallocatechin. Not only was the mass of E. grisescens larvae fed on plants previously infested with E. grisescens or treated with WOS significantly lower than that of larvae fed on controls, but also artificial diet supplemented with epicatechin, (+)-catechin or epigallocatechin gallate reduced larval growth rates. In addition, the exogenous application of jasmonic acid, ethylene or auxin induced the biosynthesis of the three catechins, which, in turn, enhanced the resistance of tea plants to E. grisescens, leading to the coordination of the three signalling pathways. Our results suggest that the three catechins play an important role in the defences of tea plants against E. grisescens.

Analysis of Catechins in Gambir West Sumatra

Gambir contains functional compounds that are included in the class of polyphenol compounds. The polyphenol compounds in gambir are mainly catechins, a natural substance that has antioxidant properties. The purpose of this study was to obtain catechin compounds from Gambir extract, to determine the solvent concentration and the right extraction temperature to obtain catechin compounds in Gambir, and to increase the selling value of Gambir latex in the Farmer community. To get the results of catechins in Gambir, this research was carried out using the infundation method. The yield of the extract was mostly found at a solvent concentration of 45% ethanol, a temperature of 105 oC and a time of 3 hours, namely 81%. Qualitative test using FeCl3 reagent can be seen that in the filtrate extracted from gambir there are catechins which show a blackish green color when dropped with FeCl3

The effect of storage time on tea Polyphenols, catechin compounds, total flavones and the biological activity of Ya’an Tibetan tea ( Camellia sinensis )

The content of tea polyphenols (TPP), tea total flavones (TFS) and tea catechin compounds in Ya’an Tibetan tea after different storage times was investigated, and the α-glucosidase inhibition activity and antioxidative activity of tea were measured. Moreover, the correlation between the levels of tea catechins in Ya’an Tibetan tea with different storage years and their bioactivities were evaluated. During the period of storage, the content of Tibetan tea polyphenols decreased, and the content of Tibetan tea flavonoids increased significantly. Five catechins were identified in Ya’an Tibetan tea using UPLC-QqQ-MS/MS, and the Ya’an Tibetan tea had diverse antioxidant activities and α-glucosidase inhibitory activities over different storage years, due to the various tea catechin components. (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG), and (-)-epicatechin (EC) were found to be responsible for its strong antioxidant activity and α-glucosidase inhibitory activity, indicating Ya’an Tibetan tea has potential as a functional food. Practical applications Ya’an Tibetan tea, also called as Kangzhuan brick tea, is a typical Chinese dark tea with a dark brown color. The change of the main active substances and its bioactivity in Ya’an Tibetan tea during a long-term storage was obtained in this study. These findings have provided important reference basis for people to have a better understanding of the chemical constituents and bioactivity of Ya’an Tibetan tea which store for a long time. Moreover, our study showed Ya’an Tibetan tea has high antioxidant activity and α-glucosidase inhibitory activity. These findings will improve product quality and upgrade Ya’an Tibetan tea industry, and promotes Tibetan tea economic development.

Utilization Of Gambir Leaf Extract (Uncaria gambir Roxb) As A Chicken Meat Preservative

Gambier leaf extract is a latex extract from the leaves of the gambier plant and contains catechin compounds that act as antimicrobials. In order to increase the shelf life and minimize the use of synthetic chicken meat preservatives, this study was carried out with the aim of knowing the administration of gambir leaf extract (Uncaria gambir Roxb) as a chicken meat preservative. This study used a factorial 3 x 5 completely randomized design (CRD) with 3 replications. Factor I is various doses of gambir leaf extract, namely E1 (1% gambier leaf extract with aquadest solvent), E2 (1% gambier leaf extract with Castrol oil, tween and aquadest solvents), E3 (2% gambier leaf extract with Castrol oil solvent, tween and aquadest) and Factor II is the length of fermentation (1 day, 2 days, 3 days, 4 days and 5 days). Variables observed included air content (highest yield at concentration E2 = 77.56), Ph (highest yield at concentration E2 = 5.57), and total microbes (highest yield at concentration E = 7.73 CFU/g). The results showed that the dose of gambier leaf extract had no significant effect (P&gt;0.05) on the water content and pH of chicken meat, but had a very significant effect (P&lt;0.01) on the total microbial meat. Storage time had no significant effect (P&gt;0.05) on water content, pH and the number of microbes in chicken meat. There was no interaction between the dose of gambier leaf extract and storage time.

Identifying the natural compound Catechin from tropical mangrove plants as a potential lead candidate against 3CLpro from SARS-CoV-2: An integrated in silico approach

SARS-CoV-2, a member of beta coronaviruses, is a single-stranded, positive-sense RNA virus responsible for the COVID-19 pandemic. With global fatalities of the pandemic exceeding 4.57 million, it becomes crucial to identify effective therapeutics against the virus. A protease, 3CLpro, is responsible for the proteolysis of viral polypeptides into functional proteins, which is essential for viral pathogenesis. This indispensable activity of 3CLpro makes it an attractive target for inhibition studies. The current study aimed to identify potential lead molecules against 3CLpro of SARS-CoV-2 using a manually curated in-house library of antiviral compounds from mangrove plants. This study employed the structure-based virtual screening technique to evaluate an in-house library of antiviral compounds against 3CLpro of SARS-CoV-2. The library was comprised of thirty-three experimentally proven antiviral molecules extracted from different species of tropical mangrove plants. The molecules in the library were virtually screened using AutoDock Vina, and subsequently, the top five promising 3CLpro-ligand complexes along with 3CLpro-N3 (control molecule) complex were subjected to MD simulations to comprehend their dynamic behaviour and structural stabilities. Finally, the MM/PBSA approach was used to calculate the binding free energies of 3CLpro complexes. Among all the studied compounds, Catechin achieved the most significant binding free energy (−40.3 ± 3.1 kcal/mol), and was closest to the control molecule (−42.8 ± 5.1 kcal/mol), and its complex with 3CLpro exhibited the highest structural stability. Through extensive computational investigations, we propose Catechin as a potential therapeutic agent against SARS-CoV-2. Communicated by Ramaswamy H. Sarma

Bioaccessibility of bioactive compounds after in vitro gastrointestinal digestion and probiotics fermentation of Brazilian fruits residues with antioxidant and antidiabetic potential

The aim of this study was to analyze the aqueous and ethanolic extracts of fruits (pomegranate, jambolan, jackfruit, physalis and bitter melon) residues regarding the assessment of α-amylase inhibition, cytotoxicity and bioaccessibility of phenolic compounds, flavonoids and antioxidants after the in vitro gastrointestinal digestion and fermentation with probiotics and phenolic compounds by UFLC-DAD. The extracts showed a high rate of α-amylase inhibition, presenting a possible antidiabetic potential. The cytotoxicity test showed good response at the tested concentrations (10, 50, 100 and 1000 μg/mL). The contents of phenolics total after digestion and the fermentation, ranged from 483 ± 4 to 9816 ± 80 mg GAE/100g. ORAC method showed a significant increase in the antioxidant activity with bioaccessibility index above 100% for most extracts, ranging from 221 ± 9 to 868 ± 34%. The bioaccessibility of the catechin, protocatechuic acid, gallic, vanillic, propyl gallate and pyrocatecol compounds has been reported firsthand for some residues. Thus, bioactive compounds present in the fruit residues can be released during gastrointestinal digestion, being good sources of natural antioxidants and with promising potential benefits for human health.

Tea catechin as antiviral agent via apoptosis agonist and triple inhibitor mechanism against HIV-1 infection: A bioinformatics approach

Context: Human immunodeficiency virus (HIV) antiretrovirals that target the binding of viral enzyme are chosen as the lead solution in the treatment of HIV-1 infection, such as non-catalytic site integrase inhibitor (NCINI), nevirapine, and darunavir. There are natural compounds from specific plants that can be effective in treating HIV-1 infection such as tea catechin. Tea catechin administration causes a decrease in viral load and inhibition of entry mechanisms and an increased effect of apoptosis in infected cells. Aims: To identify the triple inhibitor mechanism in tea catechins against the three HIV-1 enzymes and apoptosis agonists through in silico approach as an innovation in handling HIV-1 infection. Methods: The 3D structure of tea catechin compounds from the database was examined, and then all target compounds were analyzed for drug-likeness, molecular docking, pathway prediction, and molecular interactions to determine the potential of tea catechin compounds as antiviral HIV-1 in silico. Results: Tea catechin compounds have the potential to serve as antiviral against HIV-1 through apoptosis agonist and triple inhibitor mechanisms. Apoptosis occurs due to the interaction of tea catechins with pro-apoptotic proteins in cells, and the epigallocatechin gallate (EGCG) compound is a class of tea catechins with the same binding position as control. Conclusions: The binding of the EGCG molecule complex results in low binding energy. Therefore, it allows EGCG acts as a triple inhibitor in HIV-1 infection.

Exploring the inhibitory potentials of Momordica charantia bioactive compounds against Keap1-Kelch protein using computational approaches.

The online version contains supplementary material available at 10.1007/s40203-021-00100-2.

Characterization of catechin microcapsules from gambier using modified flour coatings from bengkuang

Active compounds of catechin from gambier have several disadvantages, which include being difficult to dissolve in water and not easily oxidized. Therefore, to overcome these disadvantages, they are coated with starch matrix. The modified starch from jicama (bengkuang) was produced from acid hydrolysis process, precipitated with alcohol therefore, it has a helical hole, porous structure and functions as a matrix. The aim of this study was to determine the effect of modified starch from bengkuang as a matrix on the characteristics of catechins microcapsules from gambier. The treatments tested include the ratio of catechins in modified starch (25%, 50%, 75%), a speed of 6000 rpm, and stirring time of 15 minutes on the emulsification process. The parameters observed consisted of the loading capacity of catechins in coatings, morphology (SEM), antioxidant activity, and Fourier Transform Infrared (FTIR) analysis. The results of this study showed that catechins which were encapsulated at a ratio of 1:3, had the highest antioxidant activity, i.e. 15.30 ppm with morphology of the sphere being smooth. The material ratio which affects the surface of the catechin microcapsules with elemental mapping, showed that the brighter the colour, the higher the amount of catechin concentration in encapsulation. Furthermore, the FTIR analysis showed the binding of catechins ingredient in the matrix with new absorption peaks at wavelengths of 1240 cm−1, 1286 cm−1 and 1366 cm−1. Therefore, catechin microcapsules encapsulated with modified starch, have shown good resistance to air/oxygen diffusion during storage.

Exploring the potentials of some compounds from Garcinia kola seeds towards identification of novel PDE-5 inhibitors in erectile dysfunction therapy.

Erectile dysfunction (ED) is one of the main challenges occurring among men worldwide, and is characterised by trouble getting or keeping steady erection during sexual intercourse. Various drugs like sildenafil, a phosphodiesterase-5 inhibitor (PDE-5) are freely available in the pharmacies, though normally associated with several adverse. This study was designed to assess the molecular relations obtainable between catechin, garcinal, garcinoic acid and d-tocotrienol compounds isolated from Garciniakola and targeted receptor linked to ED. These processes include the molecular docking of catechin, garcinal, garcinoic acid, d-tocotrienol, and sildenafil to receptor: PDE-5 via AutoDock Vina. Following the docking of catechin, garcinal, garcinoic acid and d-tocotrienol with the PDE-5-receptor protein, we observed that all are protein inhibitors with garcinoic acid showing better binding affinity -10.0kcal/mol with PDE-5 receptor relevant to ED. Hence, the results provided insights into the development of garcinoic acid as a replacement for present ED management, with further analysis worth considering.

Six new triterpenoids from the root of Potentilla reptans and their cardioprotective effects in silico

Tormentic acid ester glucosides derivatives (1, 2 and 4), 3-oxoursane ester glycoside (3) and 11-methoxy-ursane ester glycosides (5, 6) as six new triterpenoids, along with catechin were isolated from the ethyl acetate fraction of Potentilla reptans root (Et) methanolic extract. The structures of the compounds were elucidated by 1D, 2D NMR, IR and MS spectroscopy. Additionally, isolated triterpenoid compounds (1–6) and catechin were evaluated for their cardioprotective effects via glycogen synthase kinase 3β (GSK-3β) and glucocorticoid regulated kinase-1 (SGK1) protein kinase inhibition by Molecular Docking. Compound 1 and catechin (compound 7) exhibited significant inhibitory effects against GSK-3β and SGK1 protein kinases with a binding energy value −9.1 and −8.8 kcal/mol, respectively. Hence, Et can be a suitable natural candidate to protect cardiomyocytes injury.

The Role of Catechin Compounds and Its Derivates to Mitigate Methane Gas Production in the Rumen Fermentation

Enteric fermentation and its corresponding to methane emissions take place in many wild and domestic ruminant species, such as deer, buffalo, cattle, goats, sheep. Ruminant animals are different from other animals in that they have a rumen, a large fore-stomach with a complex microbial environment. A resulting of this process is methane (CH4), which has a global warming potential (25 times that of carbon dioxide (CO2)). Because the digestion process is not 100% efficient, some of the energy intake is lost in the form of methane. Recently, natural plant products, such as tea leaves which are often inexpensive and environmentally safe have been introduced in methane mitigation strategies. Tea leaves have potential for use as an additives in ruminant diets. The adding of catechin 10-40 g/Kg DM were able to declined methane emission 7.4–13.5%. Furthermore, catechin could decrease the methane production. Catechin decreased CH4 production both in vitro and in vivo. Catechin causes direct inhibition of methanogens as well as may act as hydrogen sinks during degradation by rumen microbes via cleavage of ring structures and reductive dehydroxylation reactions. The objective of this paper is to review existing knowledge related to discuss how catechins can act as methane-lowering agents from rumen fermentation on ruminants.

Monitoring Processes and Improvement of Wine Quality by Determining of Catechin and Phenolic Compounds in Slovakian Wines

Monitoring Processes and Improvement of Wine Quality by Determining of Catechin and Phenolic Compounds in Slovakian Wines

Bioactive compounds in the leaves of Baccharis dracunculifolia: extraction process and characterization

Baccharis dracunculifolia has been used in popular medicine because of its bioactive properties, which include anti-inflammatory, antiulcerative and hepatoprotective potentials. A 2³ central composite rotational design was used to define the best conditions for extracting the bioactive compounds from the leaves of Baccharis dracunculifolia. The parameters studied included the solvent concentration, time and temperature of extraction and the influence of these on the total phenolics content and antioxidant activity. The best conditions were 95 % methanol (v/v), 20 min extraction time, and 70 °C temperature. Under the optimized conditions, high contents of total phenolic compounds (72.5 mg GAE g-1) and high DPPH (865.6 µmol TE g-1) and ABTS (331.11 μmol TE g-1) free radical scavenging capacity and a high ferric reducing antioxidant power (1558.00 μmol FeSO4.7H2O g-1), were obtained. The extract also showed promising anti-microbial activity, demonstrating fungistatic action against C. tropicalis and C. albicans (5 mg mL-1 and 7 mg mL-1, respectively) and bacteriostatic effect against Escherichia coli (60 e 70 mg mL-1), Salmonella enterica typhimurium (40; 60 and 70 mg mL-1) and Staphylococcus aureus (4 mg mL-1). HPLC-DAD analysis showed an extract rich in the phenolic compounds catechin (0.659 mg g-1), caffeic acid (1.135 mg g-1), p-coumaric acid (0.772 mg g-1), ferulic acid (6.24 mg g-1), pinocembrina (0.155 mg g-1) and rutin (0.037 mg g-1).

Phytochemical Constituents of Ulva Lactuca and Supplementation to Improve The Nile Tilapia (Oreochromis Niloticus) Haemato-Biochemical Status

This study was carried out to investigate the phytochemical constituents and biological screening of green algae (Ulva lactuca ) methanolic crude extract. The HPLC spectrum profile identified seven phenolic and flavonoid compounds namely: catechin, chlorogenic ,caffeic, quercetin, and major compounds, ellagic acid with 60.87 % and rutin with 33.40% of total area. The GC profile of fatty acids portions represented to relative distribution percentage were 9 compounds, the major fatty acids are lauric acid 55.0 % , caprylic acid 21.2 % , capric Acid was 19.8 and palmitic acid was 1.94% . The 17 amino acids produced from GC spectrum , the percentage of total amino acid were 25.98% .The most abundant amino acids were glutamic acid 2.34% , alanine 2.22 and aspartic 2.09, leucine 1.33 , valine 1.26 , phenylalanine 1.0 , therionine 0.98 and isoleucine 0.9%. of total amino acid. Tilapia (Oreochromis Niloticus) diets were divided into Ulva fermentation and multi enzymes, groups each with three different supplementations (LC, PRO, and LC + PRO). The result recorded the diets containing fermented Ulva with L-carnitine, probiotic ( LC+PRO) was the highest level of red blood cell ( RBCs , HGB) by 1.97 cmm , 10.63 g/d . Similarly, increase of Hematocrit (HCt) , WBCs, platelets, and lymphocytes due to the highest level of protein, albumin, and globulin in this diets also, U. lactuca contains a number of complex carbohydrates and polysaccharides. This study has revealed that U. lactuca seaweed is a rich source of protein ( 22% ) which is nutritionally superior to the terrestrial plant proteins and can be used to provide significant proportions of the protein requirements of fish as well as for human.

CEP55 Inhibitor: Extensive Computational Approach Defining a New Target of Cell Cycle Machinery Agent.

Purpose: Centrosomal protein 55 (CEP55) is a pivotal protein for cytokinesis during cell division. This study aimed to provide a comprehensive information about the CEP55 gene, including its expression pattern in several cancer types, conduct functional domain analysis across species, and perform a computational approach for potential inhibitors of CEP55. Methods: The expression levels of CEP55 in different cancers were analyzed using the Oncomine and TCGA databases. Evolutionary analysis of the CEP55 gene in various species was performed using MEGA-X software. Molecular docking analysis was used to screen the binding affinity of several natural products on CEP55–ALIX binding interaction. Results: High CEP55 expression was observed in 16 datasets of different cancer types. The high expression of the CEP55 protein was associated with worse outcomes in cancer treatments. Phylogenetic and evolutionary analyses revealed that the amino acid residues essential for CEP55 binding and localization were mostly conserved across vertebrates. Seventeen plant-based compounds were docked against the CEP55 protein to determine their binding affinities and illustrated specific sites of interaction for predicting novel protein–drug interactions. Flavanol compounds epigallocatechin gallate and catechin possessed superior binding affinity to all other compounds owing to the substitution of gallic ester or hydroxyl groups on the C3 position. Conclusion: This study provides comprehensive information about the CEP55 gene and insights for designing potent inhibitors against CEP55 signaling.

Comparative study of catechin levels from green tea, oolong tea and black tea product with various treatments

Background: Tea is a refreshing drink that contains polyphenol compounds, namely catechins that are used for medicine and cosmetics. This study was to assess the content of catechin compounds in green tea, oolong and black tea products from Indonesia, China and Taiwan. Methods: Some tea products are brewed at varying temperatures (75±2; 85±2 and 95±20 C) and times (5; 10 and 15 minutes). Identification of catechin compounds was carried out using chemical reagents and UV spectrophotometry. The level of cathecin in tea products were analyzed by spectrophotometer at 280 nm wavelength. Results: The results obtained indicate that green tea, oolong tea and black tea contain epigallocatechin-3-gallate (EGCG) compounds according to the color change based on chemical reagents and for UV spectrum analysis which has λmax in the range 268-274 nm. The results of quantitative tests using UV-Vis spectrophotometry showed that the green tea samples gave the highest levels of catechins followed by oolong tea and black tea with brewing temperature at 95±20 °C. Conclusion: The catechin content of tea obtained from various products varies according to the type of processing method and the brewing temperature. Therefore, this study is expected to provide information related to catechin content to the public and researchers.