Main Catechin Research Articles

Measurement of four main catechins content in green tea based on visible and near-infrared spectroscopy using optimized machine learning algorithm

Measurement of four main catechins content in green tea based on visible and near-infrared spectroscopy using optimized machine learning algorithm

Investigating the inhibition of xanthine oxidase by five catechins: Kinetic studies, spectroscopy, molecular docking, and dynamics simulations

Catechins compounds from tea have demonstrated significant inhibitory effects on xanthine oxidase (XOD). However, the precise inhibitory mechanisms of the main catechins on XOD remain to be fully elucidated. This study explored the inhibition mechanisms and binding characteristics of five catechins (GC, EGC, EC, EGCG, and ECG) on XOD through a combination of inhibition kinetics, multi-spectroscopy analysis, molecular docking, and dynamics simulations. Among the catechins, EGCG and ECG exhibited the most potent inhibitory activities against XOD. All five catechins were found to exhibit mixed inhibition, affecting the hydrophobic groups and secondary structure of XOD predominantly through hydrophobic interactions and hydrogen bonding. Molecular dynamics simulations revealed that a 3,4,5-trihydroxybenzoic acid moiety at C3 position significantly enhances the binding affinity of EGCG and ECG to XOD. Additionally, the decrease of β-sheet and random coil induced by EGCG and ECG was found to be crucial for enhancing inhibitory activity of XOD. In vitro cell experiments showed that EGCG and ECG significantly reduced high uric acid levels of BRL-3A cell. This study elucidates the inhibitory mechanisms of catechins on XOD, paving the way for their application as XOD inhibitors to combat hyperuricemia.

Molecular Docking Analysis of Epigallocatechin 3- Gallate [EGCG] on Fatty Acids and Carnitine Transporters Family

EGCG is the main catechin present in green tea. Fatty acids can be categorized as saturated or unsaturated depending on the hydrocarbon chain and terminal carboxyl group they contain, typically with an even number of carbons. EGCG has attracted considerable interest because of its several health benefits, such as its anti-inflammatory, antioxidant, and anticancer characteristics. Yet, the precise molecular targets and mechanisms of action are not fully understood. Exploring the potential interaction of EGCG with fatty acids and carnitine transporters, which play a vital role in lipid metabolism and energy production, could provide insights into its physiological effects. Analysis of molecular docking between EGCG and fatty acid and carnitine transporters, and their interactions. A contact and binding occur between the fatty acid transporters (FABP) and VLCAD and CPTII. EGCG was subjected to molecular docking simulations with active sites of transporter families such as FABP, CPT2, and VLCAD. The docking analysis showed that EGCG has favourable binding interactions with the target transporters, involving important hydrogen bonding and hydrophobic interactions. EGCG showed a strong ability to bind to the active sites of FABP and CPT2, indicating its potential to influence their functions.

Discrimination and prediction of Qingzhuan tea storage year using quantitative chemical profile combined with multivariate analysis: Advantages of MRMHR based targeted quantification metabolomics

The duration of storage significantly influences the quality and market value of Qingzhuan tea (QZT). Herein, a high-resolution multiple reaction monitoring (MRMHR) quantitative method for markers of QZT storage year was developed. Quantitative data alongside multivariate analysis were employed to discriminate and predict the storage year of QZT. Furthermore, the content of the main biochemical ingredients, catechins and alkaloids, and free amino acids (FAA) were assessed for this purpose. The results show that targeted marker–based models exhibited superior discrimination and prediction performance among four datasets. The R2Xcum, R2Ycum and Q2cum of orthogonal projection to latent structure–discriminant analysis discrimination model were close to 1. The correlation coefficient (R2) and the root mean square error of prediction of the QZT storage year prediction model were 0.9906 and 0.63, respectively. This study provides valuable insights into tea storage quality and highlights the potential application of targeted markers in food quality evaluation.

Study of the antitumor activity of the combination baicalin and epigallocatechin gallate in a murine model of vincristine-resistant breast cancer

Background: Breast cancer is one of the primary causes of death in women worldwide. Yearly, a quarter of cancer cases in women are breast cancer. The problem is aggravated by the emergence of chemotherapeutic resistance. One of the practices to overcome this problem is using natural products along with chemotherapy. Epigallocatechin Gallate (EGCG) is the main efficient catechin in green tea. Baicalin is the main active chemical constituent of Scutellaria baicalensis. Both natural products have anti-cancer and improving resistance activities. Therefore, a combination of EGCG and baicalin may afford a possible way out to overcome chemotherapeutic resistance. Methods: EGCG and baicalin were tested on Vincristine-sensitive (EMT-6/P) and Vincristine-resistant (EMT-6/V) mouse mammary cell lines. Antiproliferative and apoptotic effects were assessed for EGCG, baicalin, their combination, and Vincristine in vitro using MTT and caspase-3 assays. An in vivo study was conducted to assess the effect of EGCG, baicalin, their combination, vincristine, vincristine along with the combination in both EMT-6/P and EMT-6/V mouse mammary cell lines. The safety profile was also considered using liver enzymes and creatinine assays. Results: in vitro, EGCG and baicalin had synergistic effects in both cell lines. The combination of baicalin and EGCG as 140 and 100 µM respectively, caused an apoptotic effect higher than the single treatment of baicalin 175 µM or EGCG 125 µM, in vincristine-resistant cell lines. In vivo, the combination along with vincristine significantly enhanced the reduction of tumour size in mice implanted with EMT-6/P and EMT-6/V cell lines. According to the safety profile, the combinations of EGCG and baicalin are safe. Conclusion: The combination of baicalin and EGCG can be optimistic in improving vincristine-resistant cells to treatments.

Green tea extracts and substantial catechin derivatives: Evaluation of their potential against breast cancer

Breast cancer is one of the most predominant types of cancer. Although assorted treatment options are available to cope with breast cancer (e.g. chemotherapy, radiotherapy, surgery, hormone therapy, targeted therapy), chemotherapy regimens still hold vital importance. Studies on the discovery of drug-candidate molecules that can create an alternative in the treatment of breast cancer continue at full speed. At this point, nature has a substantial place offering great diversity. Natural products may exhibit anticancer properties directly through molecular targets such as genes or indirectly through metabolic pathways. Moreover, they may be adjuvant agents and contribute to conventional therapy, and thus, they can enhance the efficacy of chemotherapeutics or even ease their side effects. Green tea, a critical dietary source of polyphenols and flavonoids, is obtained from the minimally fermented or unfermented leaves of the Camellia sinensis L. plant and is used in traditional Chinese medicine for many important conditions, including cancer. The phytochemical content of green tea is extremely rich, including (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC); (-)-epicatechin-3-gallate (ECG) and (-)-epicatechin (EC) as the main catechins in the composition of green tea. Within the scope of our study, we proposed the cytotoxicity and toxicity comparison of the water and 80% ethanolic extract of the green tea extracts as well as of (-)-epicatechin (EC) and (-)-epigallocatechin (EGC) in terms of their cytotoxicity and toxicity based on the structure-activity relationship on breast cancer. Therefore, we tested aqueous and 80% ethanolic extracts of green tea and EGC and EC on MDA-MB-231, MDA-BMB-468, MCF-7 and SK-BR-3 breast cancer cells. Their toxicity on healthy rat myoblastoma H9c2 cells was further examined. Resazurin reduction assay was used to detect cytotoxicity and toxicity. Both water and 80% ethanolic extract of green tea exhibited remarkable cytotoxicity on MCF-7 cancer cells deserving further investigation, including phytochemical characterization of the extract. Epigallocatechin was also cytotoxic on MCF-7 cells with an IC50 value of 20.07 µM. The possible therapeutic potentials of green tea extracts and their substantial catechin derivatives were assessed for breast cancer therapy.

In vitro activity of various Kenyan tea extracts against HeLa human cervical cancer cell line and molecular docking of tea catechins on high-risk HPV16E6 protein

Tea (Camellia sinensis) has been revealed to possess potential anticancer properties attributed to its catechin content. This study aimed to investigate the growth-inhibitory effects of various tea extracts on the HeLa cell line and molecular docking analysis of catechins on Human papillomavirus16 oncoprotein 6 (HPV16E6). Different catechins content in black, green, and purple tea were determined by using High-performance liquid chromatography (HPLC); molecular docking of four main catechins on HPV16E6 and in vitro antiproliferative activity and cell apoptosis assay were carried out. Molecular docking results suggested that the tea catechins have the potential to bind to the HPV16 E6 oncoprotein involved in cervical cancer development. The antiproliferative assay results indicated that purple tea had the highest inhibitory activity at both 24 h and 48 h, with IC50 values of 121.1 ± 3.25 μg/mL and 100.1 ± 3.76 μg/mL respectively, followed by green tea with 168.9 ± 12.59 μg/mL and 124.7 ± 3.53 μg/mL IC50 while black tea showed the least effectiveness with IC50 of 221 ± 19.35 μg/mL and 159.6 ± 2.33 μg/mL. DNA fragmentation, a characteristic of apoptosis, was observed in cells treated with the tea extracts. All three tea extracts demonstrated potential anti-cervical cancer activity bIy inhibiting cell proliferation and inducing apoptosis. The tea catechins showed promising interactions with the HPV16 E6 oncoprotein.

Differences in the quality of black tea (Camellia sinensis var. Yinghong No. 9) in different seasons and the underlying factors

Spring green tea is usually considered to be better than summer green tea. Whether this phenomenon applies to black tea is unknown. Black tea produced using Camellia sinensis var. Yinghong No. 9 leaves is popular in South China and analyzed in the study. The taste and color quality of the infusion was higher for spring tea than for summer tea. Compared with summer tea, the main catechin contents were lower in spring tea, whereas caffeine and total amino acid contents were higher, especially glutamic acid, which may be responsible for the differences between teas. Moreover, spring tea had a higher theabrownin content and a lower L* value. The compounds contributing to the infusion taste and color were correlated with the chromaticity value (i.e., useful indicator of black tea quality). This study revealed the seasonal differences in Yinghong No. 9 black tea quality and the key underlying factors.

Protective mechanism of fruit vinegar polyphenols against AGEs-induced Caco-2 cell damage.

Accumulation of advanced glycation end products (AGEs) is linked with development or aggravation of many degenerative processes or disorders. Fruit vinegars are rich in polyphenols that can be a good dietary source of AGEs inhibitors. In this study, eight kinds of vinegars were prepared. Among them, the highest polyphenol and flavonoid content were orange vinegar and kiwi fruit vinegar, respectively. Ferulic acid, vanillic acid, chlorogenic acid, p-coumaric acid, caffeic acid, catechin, and epicatechin were main polyphenols in eight fruit vinegars. Then, we measured the inhibitory effect of eight fruit vinegars on fluorescent AGEs, and found that orange vinegar had the highest inhibitory rate. Data here suggested that orange vinegar and its main components catechin, epicatechin, and p-coumaric acid could effectively reduce the level of ROS, RAGE, NADPH and inflammatory factors in Caco-2 cells. Our research provided theoretical basis for the application of orange vinegar as AGEs inhibitor.

Developmental neurotoxicity evaluation of three Chinese herbal medicines in zebrafish larvae by means of two behavioral assays: Touch-evoked response and light/dark transition

Chinese herbal medicine (CHM) is used among pregnant women. However, the question of its safety during pregnancy remains unclear. The use of these products relies on history of use data but there are specific toxicities like developmental neurotoxicity that are clearly understudied. Here we use the zebfrafish embryo developmental toxicity assay (ZEDTA) in combination with two behavioral assays: touch-evoked response and Light/Dark (L/D) transition assay to evaluate the neuro/developmental toxicity of three herbal products commonly used in CHM [Chinese name (abbreviation; part of the plant and Scientific name]: tian ma (TM; tuber form Gastrodia elata Blume), lei gong teng (LGT; root and rhizome of Tripterygium wilfordii Hook.f) and cha ye (green tea, leaves from Camellia sinensis (L.) Kuntze). In case significant alterations were detected, single components with potential exposure during pregnancy were identified in the literature and further tested. TM had no neurodevelopmental toxic potential in zebrafish embryos, while LGT and its main compounds triptolide and celastrol induced significant alterations in behavior. Developmental exposure to EGCG, the main catechin of green tea, also produced significant alterations in zebrafish embryos behavior after developmental exposure. A combination of ZEDTA with L/D Transition assay is proposed as a useful combination of alternative methods for DNT assessment of CHM products together with other New Approach Methodologies (NAMs).

Combination Calcium Hydroxide and Epigallocatechin-3-gallate in Dentistry: A Narrative Review

Background: Pulp capping and pulpotomy are treatments for exposed pulp due to injury. Calcium hydroxide is the gold standard material in pulp capping and pulpotomy because it stimulates reparative dentin formation in exposed pulp. Calcium hydroxide has the disadvantage of causing chronic inflammation, cell necrosis, the formation of tunnel defects, and weak antibacterial properties against certain bacteria. Epigallocatechin-3-gallate (EGCG) is the main catechin component of green tea and has potent anti-inflammatory and antibacterial properties against both gram-negative and positive bacteria. The addition of EGCG to calcium hydroxide has the potential to prevent chronic inflammation and improve the antibacterial properties of calcium hydroxide. Purpose: This review aims to explain the potential of the combination of calcium hydroxide and EGCG in dentistry. Review(s): EGCG has potent anti-inflammatory and antibacterial effects against Enterococcus faecalis. The addition of EGCG to calcium hydroxide has the potential to reduce the inflammatory effect and improve the antibacterial properties of calcium hydroxide. Conclusion: This review concludes that the combination of calcium hydroxide and EGCG has the potential to reduce the inflammatory effect and promote the antibacterial effect of calcium hydroxide. Further research is needed to prove the potential of the combination of calcium hydroxide and EGCG in dentistry as a material for pulp capping and pulpotomy.

Suppression of the excitability of rat nociceptive secondary sensory neurons following local administration of the Phytochemical, (-)-Epigallocatechin-3-gallate

The phytochemical, polyphenolic compound, (-)-epigallocatechin-3-gallate (EGCG), is the main catechin found in green tea. Although a modulatory effect of EGCG on voltage-gated sodium and potassium channels has been reported in excitable tissues, the in vivo effect of EGCG on the excitability of nociceptive sensory neurons remains to be determined. Our aim was to investigate whether local administration of EGCG to rats attenuates the excitability of nociceptive spinal trigeminal nucleus caudalis (SpVc) neurons in response to mechanical stimulation in vivo. Extracellular single unit recordings were made from SpVc neurons in response to orofacial mechanical stimulation of anesthetized rats. The mean firing frequency of SpVc wide-dynamic range neurons following both non-noxious and noxious mechanical stimuli was significantly inhibited by EGCG in a dose-dependent and reversible manner. The mean magnitude of inhibition by EGCG on SpVc neuronal discharge frequency was similar to that of the local anesthetic, 1% lidocaine. Local injection of half-dose of lidocaine replaced the half-dose of EGCG. These results suggest that local injection of EGCG suppresses the excitability of nociceptive SpVc neurons, possibly via the inhibition of voltage-gated sodium channels and opening of voltage-gated potassium channels in the trigeminal ganglion. Therefore, administration of EGCG as a local anesthetic may provide relief from trigeminal nociceptive pain without side effects.

Dynamic Changes in Non-Volatile Components during Steamed Green Tea Manufacturing Based on Widely Targeted Metabolomic Analysis

Steamed green tea has unique characteristics that differ from other green teas. However, the alteration patterns of non-volatile metabolites during steamed green tea processing are not fully understood. In this study, a widely targeted metabolomic method was employed to explore the changes in non-volatile metabolites during steamed green tea processing. A total of 735 non-volatile compounds were identified, covering 14 subclasses. Of these, 256 compounds showed significant changes in at least one processing step. Most amino acids, main catechins, caffeine, and main sugars were excluded from the analysis. The most significant alterations were observed during steaming, followed by shaping and drying. Steaming resulted in significant increases in the levels of most amino acids and their peptides, most phenolic acids, most organic acids, and most nucleotides and their derivates, as well as some flavonoids. Steaming also resulted in significant decreases in the levels of most lipids and some flavonoids. Shaping and drying caused significant increases in the levels of some flavonoids, phenolic acids, and lipids, and significant decreases in the levels of some amino acids and their peptides, some flavonoids, and some other compounds. Our study provides a comprehensive characterization of the dynamic alterations in non-volatile metabolites during steamed green tea manufacturing.

The physiological role of green tea catechins

Green tea is one of the most popular drinks consumed in the world. Important components contained in green tea and having antioxidant and anticarcinogenic properties are catechins - organic substances belonging to the class of polyphenolic compounds. Green tea contains 4 main catechins: (-)-epicatechin, (-)-epicatechin-3-gallate, (-)-epigallocatechin and (-)-epigallocatechin-3-gallate. This review summarizes the results of key studies, predominantly performed over the last 5 years, which provide evidence that catechins in green tea protect against ultraviolet radiation, can improve the quality of life of patients suffering from cancer, cardiovascular, neurodegenerative, viral, infectious diseases, obesity and a number of other pathologies, as well as serve as a measure for the prevention of these diseases in healthy individuals. The most potent catechin found in green tea has been shown to be (-)-epigallocatechin-3-gallate. The anticarcinogenic effects of (-)-epigallocatechin-3-gallate in the case of prostate cancer, breast cancer, colorectal cancer are presented. The powerful antioxidant activity of catechins can form the basis for the prevention of the development of infectious and viral diseases, as well as improve the quality of life of patients with metabolic syndrome and obesity. Thus, green tea is not only a tonic drink, but also an important tool for the prevention and treatment of human diseases, in the pathogenesis of which free radical oxidation and oxidative stress play an important role. The areas of practical application of green tea catechins can be the treatment of malignant tumors (during a course of chemotherapy or radiation therapy), the treatment of viral, infectious and cardiovascular diseases, skin protection from ultraviolet rays, etc.

EGCG inhibits hypertrophic scar formation in a rabbit ear model.

Hypertrophic scarring is a common skin fibro-proliferative disease, but currently there has no satisfactory drugs for anti-scar treatments. Previous study showed that epigallocatechin gallate (EGCG), the main catechin in green tea, improved wound healing and tissue fibrosis in both rats and mice. In the present study, the therapeutic effects of EGCG on hypertrophic scar were analyzed using a rabbit ear hypertrophic scar model. A rabbit ear model of hypertrophic scarring was used. DMSO, 0.5mg EGCG/wound, 1.0mg EGCG/wound or triamcinolone were injected subcutaneously once a week for 4 weeks. The scar elevation index (SEI) was measured using HE staining images, the collagen fibers were examined by Masson' trichrome staining images, and the number of capillaries in hypertrophic scar were calculated by CD31 staining images. The mRNA levels in the scar tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Gross observation and histological evaluation showed the inhibitory effects of EGCG on hypertrophic scar formation at both doses, and decreased scar height and SEI were detected. EGCG also attenuated the mean collagen area fraction and decreased the number of capillaries in scar tissues. qRT-PCR revealed that EGCG significantly inhibited the mRNA expression of TGF-β1, Col I, Col III, α-SMA, and eNOS. EGCG may serve as a useful candidate therapeutic drug for hypertrophic scar via inhibiting fibrotic gene expression and suppressing angiogenesis.

Identification and Quantification of Anthocyanin and Catechin Compounds in Purple Tea Leaves and Flakes.

Tea is the first most popular beverage worldwide and is available in several selections such as black (fully oxidized), Oolong (partially oxidized) and green (non-oxidized), in addition to purple tea, an emerging variety derived from the same tea plant (Camellia sinensis). This study investigated purple tea leaves (non-oxidized) and flakes (water extractable) to thoroughly identify their composition of anthocyanins and catechins and to study the effect of a water extraction process on their compositional properties in comparison with green tea. Anthocyanin and catechin compounds were separated and quantified using UPLC, and their identity was confirmed using LC-MS/MS in positive and negative ionization modes. Delphinidin was the principal anthocyaninidin in purple tea, while cyanidin came in second. The major anthocyanin pigments in purple tea were delphinidin-coumaroyl-hexoside followed by delphinidin-3-galactoside and cyanidin-coumaroyl-hexoside. The water extraction process resulted in substantial reductions in anthocyanins in purple tea flakes. There were no anthocyanin compounds detected in green tea samples. Both purple and green tea types were rich in catechins, with green tea containing higher concentrations than purple tea. The main catechin in purple or green tea was epigallocatechin gallate (EGCG) followed by either epicatechin gallate (ECG) or epigallocatechin (EGC), subject to tea type. The extraction process increased the concentration of catechins in both purple and green tea flakes. The results suggest that purple tea holds promise in making healthy brews, natural colorants and antioxidants and/or functional ingredients for beverages, cosmetics and healthcare industries due to its high content of anthocyanins and catechins.

Preventive Effect of Epigallocatechin Gallate, the Main Component of Green Tea, on Acute Lung Injury Caused by Air Pollutants.

Reducing the health hazards caused by air pollution is a global challenge and is included in the Sustainable Development Goals. Air pollutants, such as PM2.5, induce respiratory and cardiovascular disorders by causing various inflammatory responses via oxidative stress. Catechins and polyphenols, which are components of green tea, have various protective effects, owing to their antioxidant ability. The main catechin in green tea, epigallocatechin gallate (EGCG), is potentially effective against respiratory diseases, such as idiopathic pulmonary fibrosis and asthma, but its effectiveness against air-pollution-dependent lung injury has not yet been investigated. In this study, we examined the effect of EGCG on urban aerosol-induced acute lung injury in mice. Urban aerosol treatment caused increases in inflammatory cell counts, protein levels, and inflammatory cytokine expression in the lungs of ICR mice, but pretreatment with EGCG markedly suppressed these responses. Analyses of oxidative stress revealed that urban aerosol exposure enhanced reactive oxygen species (ROS) production and the formation of ROS-activated neutrophil extracellular traps (NETs) in the lungs of mice. However, ROS production and NETs formation were markedly suppressed by pretreating the mice with EGCG. Gallocatechin gallate (GCG), a heat-epimerized form of EGCG, also markedly suppressed urban aerosol-dependent inflammatory responses and ROS production in vivo and in vitro. These findings suggest that EGCG and GCG prevent acute lung injury caused by urban aerosols through their inhibitory effects on ROS production. Thus, we believe that foods and medications containing EGCG or GCG may be candidates to prevent the onset and progression of acute lung injury caused by air pollutants.

Optimization of enzymatic synthesis of theaflavins from potato polyphenol oxidase

Theaflavin (TF), a chemical component important in measuring the quality of fermented tea, has a strong natural antioxidant effect and many pharmacological functions. Enzymatic oxidation has become a widely used method for preparing TFs at the current research stage. Using plant exogenous polyphenol oxidase (PPO) to enzymatically synthesize TFs can significantly increase yield and purity. In this study, tea polyphenols were used as the reaction substrate to discuss the optimal synthesis conditions of potato PPO enzymatic synthesis of theaflavins and the main products of enzymatic synthesis of TFs. The optimal enzymatic synthesis conditions were as follows: pH of the reaction system was 5.5, reaction time was 150min, substrate concentration was 6.0mg/mL, reaction temperature was 20°C, and the maximum amount of TFs produced was 651.75μg/mL. At the same time, high-performance liquid chromatography was used to determine the content of theaflavins and catechins in the sample to be tested, and the dynamic changes and correlations of the main catechins and theaflavins in the optimal enzymatic system were analyzed. The results showed that epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) are all the main substrates synthesis of TFs. The main substrate of TFs and its strongest enzymatic catalytic effect on EGCG make theaflavin-3,3'-digallate (TFDG) the most important synthetic monomer. In this study, theaflavins were synthesized by polyphenol oxidase catalysis, which laid a foundation for industrialization of theaflavins.

Design, synthesis, and biological evaluation of polyphenol derivatives as DYRK1A inhibitors. The discovery of a potentially promising treatment for Multiple Sclerosis

Green tea and its natural components are known for their usefulness against a variety of diseases. In particular, the activity of main catechin Epigallocatechin gallate (EGCG) against Dual-specificity tyrosine-(Y)-phosphorylation Regulated Kinase-1A (DYRK1A) has been reported; here we are showing a structure–activity relationship (SAR) for EGCG against this molecular target. We have studied the influence of all four rings on the activity and the nature of its absolute geometry. This work has led to the identification of the more potent and stable trans fluoro-catechin derivative 1f (IC50 = 35 nM). This molecule together with a novel delivery method showed good efficacy in vivo when tested in a validated model of multiple sclerosis (EAE).

Is it possible to treat nonalcoholic liver disease using a flavanol-based nutraceutical approach? Basic and clinical data.

Nonalcoholic fatty liver disease (NAFLD) is characterized by a spectrum of diseases, ranging from simple steatosis to hepatocellular carcinoma. The main factors for NAFLD are closely related to obesity, insulin resistance, intestinal microbiota alterations, hyperinsulinism, low-grade systemic inflammation, nitroxidative stress, lipid peroxidation, and mitochondrial dysfunction. Currently, the treatment of NAFLD is based on diet and exercise because, to date, there is no specific pharmacological agent, already approved, that raises the need for new therapeutic strategies. Nutraceuticals, such as polyphenols, have potential beneficial effects for health. In this article, the beneficial effects of epigallocatechin-3-gallate (EGCG) and (-)-epicatechin (EC) are discussed. EGCG is the main catechin in green tea, which has shown in various studies its potential effect preventing and treating NAFLD since it has shown antihyperlipidemic, anti-inflammatory, antifibrotic, antioxidant, and improvement of liver lipid metabolism. However, it has been found that excessive consumption may cause hepatotoxicity. EC is widely distributed in nature (fruits and vegetables). This flavanol has shown many beneficial effects, including antihypertensive, anti-inflammatory, anti-hyperglycemic, antithrombotic, and antifibrotic properties. It increases mitochondrial biogenesis, and it also has effects on the regulation of synthesis and metabolism of lipids. This flavanol is a nontoxic substance; it has been classified bythe United States Food and Drug Administration as harmless. The EC-induced effects can be useful for the prevention and/or treatment of NAFLD.