Compounds Catechin Research Articles

In Vivo Antimalarial Activity of the Leaf Extract of Osyris quadripartita Salzm. ex Decne and Its Major Compound (-) Catechin.

Background The leaves of Osyris quadripartita Salzm. ex Decne, endemic to Ethiopia, are traditionally used for the treatment of malaria. Previous phytochemical investigations of Osyris species showed the presence of flavonoids, anthracene derivatives, and sesquiterpene lactones as the main constituents. The aim of the present study was to investigate the antimalarial activity of the leaf extract of O. quadripartita and its isolated constituent against mice infected with Plasmodium berghei. Methods Isolation of a compound was carried out on silica gel column chromatography of the extract eluting with gradient mixtures of CHCl3/MeOH. Structural elucidation of the isolated compound was achieved by ESI-MS and 1D-and 2D-NMR spectral data. Peter's 4-day suppressive test method was used to determine the antimalarial activity of the test substances. Level of parasitemia, survival time, and body weight change were used to determine the antimalarial activity of the test substances. Results (–) Catechin was isolated and characterized from the hydroalcoholic extract of O. quadripartita. At a concentration of 400 mg/kg, both the extract and (–) catechin exhibited antimalarial activity with the highest chemosuppression values of 70.61% and 64.26%, respectively. Conclusion These findings indicate that O. quadripartita is endowed with genuine antimalarial activity attributed in part, to its (–) catechin content. Hence, the present study may validate the traditional use of the plant for the treatment of malaria.

A Comprehensive Review on Beneficial Effects of Catechins on Secondary Mitochondrial Diseases.

Mitochondria are the main sites for oxidative phosphorylation and synthesis of adenosine triphosphate in cells, and are known as cellular power factories. The phrase “secondary mitochondrial diseases” essentially refers to any abnormal mitochondrial function other than primary mitochondrial diseases, i.e., the process caused by the genes encoding the electron transport chain (ETC) proteins directly or impacting the production of the machinery needed for ETC. Mitochondrial diseases can cause adenosine triphosphate (ATP) synthesis disorder, an increase in oxygen free radicals, and intracellular redox imbalance. It can also induce apoptosis and, eventually, multi-system damage, which leads to neurodegenerative disease. The catechin compounds rich in tea have attracted much attention due to their effective antioxidant activity. Catechins, especially acetylated catechins such as epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), are able to protect mitochondria from reactive oxygen species. This review focuses on the role of catechins in regulating cell homeostasis, in which catechins act as a free radical scavenger and metal ion chelator, their protective mechanism on mitochondria, and the protective effect of catechins on mitochondrial deoxyribonucleic acid (DNA). This review highlights catechins and their effects on mitochondrial functional metabolic networks: regulating mitochondrial function and biogenesis, improving insulin resistance, regulating intracellular calcium homeostasis, and regulating epigenetic processes. Finally, the indirect beneficial effects of catechins on mitochondrial diseases are also illustrated by the warburg and the apoptosis effect. Some possible mechanisms are shown graphically. In addition, the bioavailability of catechins and peracetylated-catechins, free radical scavenging activity, mitochondrial activation ability of the high-molecular-weight polyphenol, and the mitochondrial activation factor were also discussed.

Identification of high-value bioactive constituents in Northern European willow varieties: S.X. Dasyclados, Endeavour, Cheviot, Tora, Resolution, S. Purpurea, Terranova, endurance

Willow trees have maintained their place in medicine for many years as they are herbal source of various cures. Willow varieties are considered to contain a wide range of anti-inflammatory and anti-bacterial species such as salicylates and flavonoids. The current work is centred on the presence of high bioactive pharmaceutical constituents other than salicin such as flavan-3-ol catechin, salicortin, and other complex compounds, which contribute to the total medical value of willow extracts. To evaluate the distribution of these bioactives, bark, and wood fractions of 8 different willow varieties (S.X. Dasyclados, Endeavour, Cheviot, Tora, Resolution, S. Purpurea, Terranova, Endurance) were extracted using dispersive solid phase extraction and then analysed using LC-MS comprising a quadrupole time-of-flight spectrometer. Indeed, various high value constituents such as salicortin, catechin, triandrin, acacetin-5-O-xyloside, picein, apigenin-7-O-glucoside, vitexin-2-rhamnoside, luteolin-7-glucoside, catechin gallate, and kaempferol as well as giberellic and 5-methoxysalicylic acid were detected in bark and wood fractions of the willow varieties 80:20 ethanol/water extracts.

Solubilization and extraction of valuable compounds from peanut skin in subcritical water

Subcritical water extraction (SWE) is a process for extracting valuable compounds of catechin and epicatechin from the skin of the peanut (Arachis hypogea). The research's objective was to identify the best extraction conditions for recovering total catechin compounds (TCC), total epicatechin compounds (TEC), and total yield from peanut skin. The solubility of yield in subcritical water was determined using the Chrastil and Del Valle Aguilera models. The best conditions were 13.56 MPa, 11.66 ml/min, 160°C with responses of TCC 10.81 mg/g, TEC 8.41 mg/g, and yield 0.268 g/g. High pressure and temperature conditions were conducive to TEC recovery, whereas high flow rate conditions were suitable to TEC and total yield enhancement. The Chrastil model fits the solubility of yield in subcritical water effectively since it has the lower average absolute relative deviation, which is 85.507% compared to Del Valle Aguilera of 85.509%. The Chrastil and Del Valle Aguilera model was not suitable for the solubility of peanut skin extract due to high percentage of AARD. Practical applications The catechin and epicatechin from peanut skin were frequently recovered using a hazardous solvent in a traditional extraction procedure. Subcritical water extraction is one of the methods for overcoming the toxicity of solvents. The best condition for obtaining maximum total catechin compounds (TCC), total epicatechin compounds (TEC) was determined using response surface methodology. Furthermore, in this work, a semi-empirical model was utilized to evaluate the effect of parameters to improve the solubility of bioactive compounds. TEC recovery was enhanced by high pressure and temperature, while TEC and total yield augmentation were enhanced by high flow rate.

차나무 부위별 추출물의 이화학적 특성

Background: There are various physiologically active substances in Camellia sinensis leaves, and much research has been conducted on it, however, the properties of other parts such as branch, flower, seed, and root are still unknown. Therefore, in this study, we checked the physicochemical properties of each part of C. sinensis.BRMethods and Results: In this study, we prepared a 70% ethyl alcohol extract of each part of C. sinensis and determined their yield, total polyphenol and total flavonoid contents, antioxidant activity, components [using high performance liquid chromatography (HPLC)], and α-glucosidase inhibitory activity. The yield was highest in the flower extract, and the total polyphenol content and antioxidant activity tended to be high in the order of leaf, root, branch, flower, and seed. Analysis of the catechin compounds using HPLC, confirmed that epigallocatechin (EGC) and epigallocatechin gallate (EGCG) were mostly present in the leaf, but epicatechin (EC), gallocatechin gallate (GCG), and gallocatechin (GC) were present in varying concentrations in each part. The inhibitory activity of α-glucosidase was higher than that of acarbose, a hypoglycemic agent, in all parts except the seed, which showed no activity. Furthermore, significantly higher α-glucosidase inhibitory activity was confirmed in the root.BRConclusions: Apart from the leaves, which have been widely used and studied in the industry, the C. sinensis root and brances showed high activity. In particular, the α-glucosidase inhibitory activity was very high, confirming the possibility of using the roots and brances discarded by the tea leaf industry as an antidiabetic material.

Henol analysis by HPLC-DAD, and antimicrobial and antioxidant activities of two species extracts of Pelargonium: P. graveolens and P. zonale

Introduction. Pelargonium graveolens is a well-known ethno-medicinal plant used in traditional medicine, whereas Pelargonium zonale has not been investigated thoroughly. Objective. This study was designed to quantify phenolic compounds in extracts of Pelargonium graveolens and Pelargonium zonale, evaluate their antioxidant activities, establish a method for assaying phenolic compounds by HPLC-DAD, and determine the antimicrobial activity of these extracts. Material and methods. Aerial parts polyphenols were extracted with solvents of different polarities. Total content of polyphenols, flavonoids, and condensed tannins were determined. Antioxidant activity was assessed by measuring free radical scavenging activity of 2,2-diphenyl-2-picrylhydrazyl (DPPH). Agilent C18 with a linear gradient elution program was performed for chromatographic separation, and disk diffusion method was used to determine antimicrobial activity. Results. Total polyphenols content ranged from 159.4 to 164.2 mg GAE/g, and that of total flavonoids from 26.92 to 63.68 mg QE/g. DPPH values of ethanol extracts reached IC50 = 91.84±0.1 μg/mL. HPLC method permitted to analyze and separate twelve phenolic compounds (Acacetin, apigenin, myrecitin, quercetin, catechin, naringin, hesperetin, galengine, flavone, tannic acid, vanillic acid, and α-tocopherol). Extracts showed moderate to strong antimicrobial activity against five strains withminimum inhibitory concentration (MIC) ranging from 0.46 to 3.9 mg/mL. Conclusion. These results confirm richness of extracts by phenolic compounds, and are strongly correlated with DPPH values. In addition, the applied method is precise, and allows simultaneous determination of 12 phenolic compounds.

Metabolic profile analysis based on GC-TOF/MS and HPLC reveals the negative correlation between catechins and fatty acids in the cottonseed of Gossypium hirsutum

BackgroundThe diversified and high value-added utilization of cotton by products can promote the sustainable development of modern agriculture. Differences in potential nutrients among varieties can be explained by variations in the composition and abundance of fatty acids, polyphenols, carbohydrates, amino acids, and organic acids. Therefore, the analysis of metabolite species and relationships in cottonseed is meaningful for the development of cotton byproducts.ResultsIn this study, the metabolomes of three representative cotton cultivars of different species were compared using untargeted GC-TOF/MS analysis. A total of 263 metabolites were identified from 705 peaks, and their levels were compared across cultivars. Principal component analysis and OPLS-DA clearly distinguish these samples based on metabolites. There were significant differences in the contents of amino acids, carbohydrates, organic acids, flavonoids, and lipids in G. hirsutum TM-1 compared with G. arboreum Shixiya1 and G. barbadense Hai7124. Notably, the bioactive nutrient compound catechin obtained from the differential metabolites significantly accumulated in TM-1. Furthermore, a comprehensive analysis using catechin and oil-related traits was conducted in core collections of Gossypium hirsutum. The results revealed the reliability of the GC-TOF/MS analysis, as well as that catechin content has a negative association with myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, arachidic acid, and total fatty acids.ConclusionThese findings suggest that untargeted GC-TOF/MS analysis could provide a new method for investigating the underlying plant biochemistry of nutrient variation in cottonseed, and that catechin content has a negative association with oil-related traits in cottonseed. This study may pave the way to exploit the value of cotton byproducts.

The Effect of Gambier Catechin Isolate on Cervical Cancer Cell Death (HeLa Cell Lines)

BACKGROUND: Cervical cancer is the second most common type of cancer in women worldwide. Human Papilloma Virus infection on the surface of the cervix is the most common cause which can cause abnormal growth of cervical cells.
 AIM: This research was conducted in vitro which aims to determine whether catechin compounds can inhibit the growth and regulation of cervical cancer cells (HeLa cell line).
 METHODS: This is experimental research using the colourimetric assay method and qualitative observation of cervical cancer cell morphology (HeLa cell line) under a fluorescence microscope. The administration of catechin compounds was tested at different concentrations to HeLa cells, namely 1000 g/ml, 500 g/ml, 250 g/ml, 125 g/ml, 62.5 g/ml, 31.25 g/ml.
 RESULTS: The smallest cell viability was obtained from a concentration of 1000 g/ml which was 5.98% while the largest cell viability was found at a concentration of 31.25 g/ml, which was 40.01%. The resulting IC50 value was 22.91 g/ml. Gambier catechin compounds have very high antioxidants because they contain an IC50 value < 50 g/ml. The effect of gambier catechin compounds on HeLa cell death can be found by increasing the percentage of dead cells. The difference in the fluorescence images of HeLa cells in the experimental group was assessed based on the percentage of the number of cells that died or underwent apoptosis, which was marked by a red or orange fluorescent image. At the concentration of IC25, 31.87% of dead cells were found, the concentration of IC50 was 51.09% of dead cells, and the concentration of IC75 was 82.51% of dead cells. The test results showed that there was a significant difference in the average percentage of cells undergoing apoptosis in all study groups with p <0.05.
 CONCLUSION: Based on research, it can be concluded that catechin compounds could inhibit the growth and regulation of cervical cancer cells (HeLa cell line). Later, it has the potential to be developed as an anticancer candidate for cervical cancer.
 Keyword: Cervical cancer, Catechin, Apoptosis, HeLa cell line, Cell death.

Antioxidant Activity, Phenolic Composition, and Hormone Content of Wild Edible Vegetables

Wild edible plants have been used since antiquity as folk medicine and as preservatives in foods. This study aimed to determine the antioxidant activities, phenolic compounds, and hormone contents of 12 species of edible wild plants belonging to 9 families, which are consumed as vegetables by the local people at Ergan Mountain in Erzincan in Turkey. Polygonum cognatum and Malva neglecta were determined to have more antioxidant enzyme activity, more phenolic compounds, and higher hormone content than the other species. The highest catalase (CAT), peroxidase (POD), glutathione reductase (GR), glutathione-s-transferase (GST) values for P. cognatum were determined as 45.12, 94.83, 36.76, and 1218.35 EU g−1, respectively. The highest superoxide dismutase (SOD) and ascorbate peroxidase (AxPOD) content for M. neglecta were determined as 97.53 EU g−1 and 81.93 EU g−1, respectively. P. cognatum is the species in which the highest levels of the hormones indolacetic acid (IAA), gibberellic acid (GA), salicylic acid (SA), cytokinin, zeatin and jasmonic acid were detected. The highest levels of caftaric acid (CA), catechin (CAE), ferulic acid (FA), malvidin-3-o-glucoside (MG), myricetin (MYR), rutin (RT), trans-coumaric acid (TPCA), tyrosol (TY), and vanilic acid (VA) compounds were found in M. neglecta. It was determined that Falcaria vulgaris species had the highest levels of ferulic acid (FA) and quercetin (QUE) phenolics. The results show that edible wild vegetables consumed and studied by the people of the region are an important source of natural antioxidants. The possibilities of using these wild plants as functional foods should be investigated.

Aktivitas Fraksi Air Kulit Batang Mahoni (Swietenia macrophylla King.) Dan Studi In Silico Senyawa Kimia Penghambat Enzim α-Glukosidase

Inhibition of the α-glucosidase can be used as antidiabetic therapy because it can reduce postprandial blood sugar levels. The stem bark of mahogany (Swietenia macrophylla King.) have properties as inhibitors of enzyme α-glucosidase. The purpose of this study was to determine the active compound of mahogany stem bark againstα-glucosidase enzyme in vitro and in silico. 96% ethanol extract of mahogany stem bark was partitioned with n-hexane, ethyl acetate and water. Testing of inhibition of α-glucosidase enzyme work done with substrate p-nitrophenyl-α-D-glucopyranoside. The water fraction was separated on silica gel column chromatography (SiO2 : dichloromethane-methanol = 10 : 1 ~ 1 : 1 and methanol).Molecular docking using AutoDock 4.2.6 was performed to predict the binding modes of α-glucosidase enzyme with chemical compound from water subfraction of stem bark mahogany. The results showed that water fraction of stem bark mahogany have antidiabetic activity with IC50 value of 1.51 µg/mL. Fraction Fr-1 gave an inhibition of 83.61 ± 1.11 %. Fr-1 contains chemical compound catechin, evodionol and swietenitin K. In silico study showed that catechin and evodionol free energy value (ΔG) -6.98 and -6.25 Kcal/mol and inhibition constanta (Ki) 7.61 and 26.18 µM.

Construction of catechin and bamboo shoot dietary fiber compounds: Their protection and release of catechin during digestion

The composite particles of the release and protective effect of catechin by embedding bamboo shoots dietary fibers-catechin (BC) with xanthan gum (GX), sodium alginate (SA), and pectin (Pec) were compared in vitro. SEM, FTIR, and TGA results suggested that the surface pores and cracks of the composite particles of GX-BC, SA-BC, and Pec-BC were reduced compared to BC, but there was no change in the structure and thermal stability. Moreover, the release amounts of catechin of BC, GX-BC, SA-BC, and Pec-BC after gastric digestion were 56.28%, 27.83%, 30.99%, and 35.40%, respectively, while the release amounts of catechin after intestinal digestion were 20.26%, 10.12%, 10.01%, and 12.14%, respectively. In addition, the fluorescence intensity and antioxidant activity of the composite particles were directly proportional to the release of catechin. Therefore, encapsulating BC with soluble polysaccharides could delay the release of catechin and retain more catechin to enter the colon. Practical applications Catechins are easily affected by gastric acid and various enzymes in vivo, which reduce their bioavailability. The enzymatically prepared bamboo shoots dietary fibers to adsorb catechin and then embedding the compound of bamboo shoots dietary fibers and catechin by soluble polysaccharides to form new composite particles, and to study the function of dietary fibers in the release and protection of catechins during digestion. In the simulated digestion process in vitro, the embedding of soluble polysaccharides could remarkably reduce the release of catechins and increase the retention percentage of catechins, and it is possible to retain more catechins to enter the colon for release, thereby exerting greater physiological effects. We believed that our findings could be to provide basis for the development of new functional foods.

Relationship between theanine, catechins and related genes reveals accumulation mechanism during spring and summer in tea plant (Camellia sinensis L.)

The tea plant (Camellia sinensis L.) is an important commercial crop. Theanine and catechins, abundant in the tea plant and represented as secondary metabolites of the tea plant, contribute to the refreshing and astringent taste of tea, respectively. In this study, three C. sinensis cultivars, ‘Baojing Huangjincha 1′ (HJC1), ‘Huangjincha 2′ (HJC2), and ‘Huangjincha 168′ (HJC168) harvested in spring and summer were used to investigate differences in theanine and catechin concentrations by high-performance liquid chromatography. The expression levels of genes associated with theanine and catechin biosynthesis were investigated using a real-time quantitative polymerase chain reaction. Results indicated that theanine, aspartic acid, serine, glutamate and alanine contents were higher in spring in three cultivars, while CsGDH1 showed higher expression in summer. As for catechins, HJC1 and HJC2 accumulated more epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) contents in summer. On the contrary, HJC168 showed higher EGCG and ECG contents in spring. CsF3H showed higher expression in spring than in summer in three cultivars. Correlation analysis indicated a positive correlation between the CsGABA-T expression and theanine contents in spring and summer (p<0.05), with the activity of GABA-T in theanine synthesis, implying that CsGABA-T might be a crucial positive regulator in theanine accumulation. Besides, most catechin compounds were positively correlated with related genes expression during summer. It was presumed that catechin synthesis contributes to catechin accumulation in summer. In summary, this study provides insights into the potential regulatory mechanisms of theanine and catechins in spring and summer.

Prediction of Anti-SARS CoV-2 Activity from Green Tea Catechin (Camellia sinensis L. Kuntze) Compound Against To Receptors Non-structural Protein 3 (6W6Y) And Non-structural Protein 5 (6M2N)

Green tea catechin compounds (Camellia sinensis L. Kuntze) have an antiviral activity such as influenza, hepatitis B, hepatitis C, herpes simplex virus, HIV, and proven in vitro antiviral influenza against NSP5 in SARS CoV. These considerations are used in this study using Non-structural Protein (NSP), namely NSP3 and NSP5 in SARS CoV-2, which have a role in viral replication and transcription. This study aims to predict the physicochemical properties according to the five rules of Lipinski's using swissADME. Prediction of toxicity with LD50 classification using the Protox II online tool. Catechin compound activity based on ligand interaction with NSP3 (PDB ID: 6W6Y) and NSP5 (PDB ID: 6M2N) receptors using Molegro Virtual Docker (MVD) 6.0. The results showed the predictions of physicochemical properties of the (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG), and (-)-epicatechin (EC) compounds fulfilled the five rules of Lipinski's. Catechin compounds have toxicity at levels 4 and 6. The activity of catechin compounds on NSP3 (PDB ID: 6W6Y) and NSP5 (PDB ID: 6M2N) receptors indicated that all catechin compounds had inhibitory activity. The best potential activity compound is (-)-epigallocatechin-3-gallate (EGCG) with a rerank score of -102.8200 and -134.1800 Kcal/mol so that EGCG can be recommended as a candidate for the SARS CoV-2 antiviral compound.

Blood pressure and blood sugar-lowering effects of purified gambir on diabetic hypertensive Wistar Kyoto rats.

Antioxidants protect people from diabetes and its cardiovascular complication. Purified gambir (Uncaria gambir Roxb.) is a potential medicinal plant for treating this condition based on the antioxidant activity of its catechin compound. This study tries to reveal the potential activity of purified gambir as a blood pressure-lowering drug while lowering blood glucose in diabetic hypertensive rats induced by oral NaCl-Prednisone and Alloxan. Rats were induced by oral NaCl 0.8% and Prednisone 5mg/kg BW for 14days to obtain hypertensive condition. Alloxan 125mg/kg BW was given intra peritoneal injection on the 8th day to obtain diabetic hypertensive condition. The animal was divided into five groups, normal control group treated with vehicle, treatment groups were treated with purified gambir at dose of 2.5; 5 and 10mg/kg BW respectively, while the positive control group were treated with a combination of captopril-glibenclamide at dose of 2.25 and 0.45mg/kg BW. All animals were treated orally for 14days. Fasting blood glucose and cardiovascular parameters (SBP, DBP, MAP, HR, BF and BV) were measured on days 1, 3, 7, and 14. NO level were measured on day 0 and day 14. Data were analyzed using two-way ANOVA followed by Duncan Multiple Range Test. The purified gambir has blood pressure and blood sugar-lowering activity (p<0.05). The NO levels of the treatment group also increased significantly (p<0.05). This study indicated that purified gambir could be an alternative medicine to manage blood glucose and blood pressure in the diabetic hypertensive model.

Antidepressant activity of phytochemicals of Mangifera indica seeds assisted by integrated computational analysis.

Mangifera indica L., also known as mango, is a tropical fruit that belongs to the Anacardiaceae family and is prized for its juiciness, unique flavour, and worldwide popularity. The current study aimed to probe into antidepressant power (ADP) of MIS in animals and confirmation of ADP with in silico induced-fit molecular docking. The depression model was prepared by exposing mice to various stressors from 9:00 am to 2:00pm during 42days study period. MIS extract and fluoxetine were given daily for 30 min before exposing animals to stressors. ADP was evaluated by various behavioural tests and biochemical analysis. Results showed increased physical activity in mice under behavioural tests, plasma nitrite and malondialdehyde (MDA) levels and monoamine oxidase A (MAO-A) activity decreased dose-dependently in MIS treated mice and superoxide dismutases (SOD) levels increased in treated groups as compared to disease control. With the peculiar behaviour and significant interactions of the functional residues of target proteins with selected ligands along with the best absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, it is concluded that catechin could be the best MAO-A inhibitor at a binding energy of -8.85kcal/mol, and two hydrogen bonds were generated with Cys406 (A) and Gly443 (A) residues of the active binding site of MAO-A enzyme. While catechin at -6.86kcal/mol generated three hydrogen bonds with Ala263 (A) and Gly434 (A) residues of the active site of monoamine oxidase B (MAO-B) enzyme and stabilized the best conformation. Therefore, it is highly recommended to test the selected lead-like compound catechin in the laboratory with biological system analysis to confirm its activity as MAO-A and MAO-B inhibitors so it can be declared as one of the novel therapeutic options with anti-depressant activity. Our findings concluded that M. indica seeds could be a significant and alternative anti-depressant therapy.

In Silico Studies on The Potential of Green Tea Catechin Compounds (Camellia sinensis) as Antiviral of SARS CoV-2 Againts Spike Glycoprotein (6LZG) and Main Protease (5R7Y)

COVID-19 is a disease caused by SARS CoV-2 by producing structural proteins and non-structural proteins. SARS CoV-2 uses a spike glycoprotein to bind ACE-2 receptors in host cells and uses main protease to replicate. This research aims to screen green tea catechin derivates as an antiviral for SARS CoV-2 through inhibition of spike glycoprotein (6LZG) and main protease (5R7Y). In silico studies carried out are molecular docking, prediction of physicochemical properties, and prediction of toxicity. The potential inhibition was assessed based on binding affinity and interaction of amino acid residues. From the molecular docking process showed that epicatechin and epigallocatechin provide inhibition to spike glycoprotein better than nafamostat indicated by binding affinity of -5.2 kcal/mol and -4.5 kcal/mol, while epigallocatechin gallate and epicatechin gallate provide inhibiton to main protease better than lopinavir with binding affinity of -8.7 kcal/mol and -8.3 kcal/mol. The results of the physicochemical properties prediction showed that only epigallocatechin gallate that did not fulfill five Lipinski's rule. Based on the toxicity class LD50, the derivates of catechin belong to classes 4 and 6. In conclusion, it can be known that epicatechin and epigallocatechin can be developed as an antiviral for SARS CoV-2.

Phytochemical component, and antioxidant and vasculo-protective activities of Taiwan cocoa polyphenols by different processing methods

Cocoa tree (Theobroma cacao L.) is a recently planted crop in Taiwan, a country located in East Asia. Taiwanese cocoa beans are appreciated globally because of their distinctive flavor and aroma. The effects of the water extracts of unfermented Taiwan cocoa beans (WUFCB) and fermented and roasted Taiwan cocoa beans (WFRCB) on the anti-oxidation, vascular protection, and variation in phytochemical components were investigated. Variations in the catechins components of WUFCB and WFRCB were examined by high performance liquid chromatography. The values of catechin compounds in WUFCB (epicatechin [EC]: 52.32 ± 0.56 mg/g, and catechin (C): 15.14 ± 0.26 mg/g) were approximately two times higher than those found in WFRCB (EC: 26.22 ± 0.48 mg/g, and C: 4.56 ± 0.10 mg/g), indicating that the fermentation and roasting steps caused decline in catechins compounds of WFRCB. In the range of 50–300 µg mL-1, both WUFCB and WFRCB depict noncytotoxicity in endothelial cells; they protect cells from H2O2-induced cytotoxicity as established by MTT assay. Meanwhile, nitric oxide (NO) levels in endothelial cells were elevated by WUFCB. In addition, WUFCB displayed radical scavenging in the acellular model and inhibited increase in reactive oxygen species (ROS) noted in endothelial cell induced by H2O2. Overall, the significant vascular protection of WUFCB is associated with increased NO formation. The decreased ROS generation against oxidative damage was attributed to abundant catechin compounds. This study establishes Taiwan cocoa polyphenol as an effective and complementary tool for preventing endothelial dysfunction and cardiovascular disease.

Alcohol exacerbated biochemical and biophysical alterations in liver mitochondrial membrane of diabetic male wistar rats – A possible amelioration by green tea

Alcohol exacerbated biochemical and biophysical alterations in liver mitochondrial membrane of diabetic male wistar rats – A possible amelioration by green tea

Prediction of the mechanism of action of catechin as superoxide anion antioxidants and natural antivirals for COVID-19 infection with in silico study.

ABSTRACTCoronavirus disease-2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus-2 attacking the lungs, which contain the most oxygen. The involvement of oxidative stress in the body and the role of antioxidant compounds, namely catechins, are thought to be able to prevent various diseases, including the COVID-19 infection virus. An in silico approach was employed between the catechins and the protein NADPH oxidase (Nox), followed by the coronavirus protease protein, to limit the generation of reactive oxygen species. This research using the in silico method seeks to predict the mechanism of action of catechin as a superoxide radical anion inhibitor and as an antiviral for COVID-19. This study carried out molecular docking simulations of catechin compounds against Nox and coronavirus proteases and then compared them with positive controls GKT136901 and remdesivir. The binding energy of catechin and Nox in a docking simulation is − 8.30 kcal/mol, which is somewhat lower than GKT136901's binding value of − 8.72 kcal/mol. Catechin and coronavirus proteases had binding energy of − 7.89 kcal/mol, which was greater than remdesivir's binding energy of − 7.50 kcal/mol. Based on in silico data, catechin as an antioxidant compound can be antiviral for COVID-19.

Optimization of UV-photo fermentation conditions theaflavin from tea leaves (Camellia sinensis) using response surface methodology (RSM) as inhibitor in SARS-CoV-2

Theaflavin (TF) is a component of fermented (enzymatic oxidation) catechin compounds synthesized during tea leaf fermentation, giving a golden yellow color, taste, and aroma to black tea. Theaflavins, which are rich in antioxidants, can treat cancer, obesity, diabetes and are potential as an inhibitor in SARS-CoV-2. Photo fermentation using ultraviolet (UV) has the advantage of penetrating the stoma cell wall in tea leaves and accelerating the oxidation of tea leaves that have gone through the milling process before the fermentation stage. This study aimed to optimize the photo fermentation process of theaflavin compounds from fresh tea leaves through response surface methodology (RSM). The highest theaflavin was obtained at a flow rate of 6 L/minute and a long irradiation time of 55 min, with a theaflavin content of 0.6705%. RSM states that the oxygen flow rate is the most influential factor with an R-Square value of 0.60814 means only 60.814% variation in data can be described by the model.