scholarly journals Rapid inactivation in vitro of SARS-CoV-2 in saliva by black tea and green tea

2020 ◽  
Author(s):  
Eriko Ohgitani ◽  
Masaharu Shin-Ya ◽  
Masaki Ichitani ◽  
Makoto Kobayashi ◽  
Takanobu Takihara ◽  
...  
Keyword(s):  
Green Tea ◽  
Clinical Studies ◽  
Virus Titer ◽  
Epigallocatechin Gallate ◽  
Black Tea ◽  
Human Saliva ◽  
Long Period ◽  
Oolong Tea ◽  
Rapid Inactivation

AbstractSaliva plays major roles in human-to-human transmission of the SARS-CoV-2. Recently we reported that black, green and oolong tea significantly inactivated SARS-CoV-2 within 1 min. Theaflavin-3,3’-di-gallate (TFDG), theasinensin A (TSA) and (-) epigallocatechin gallate (EGCG) were involved in the anti-viral activities. Here we examined how long period is required for the compounds to inactivate the virus. We also assessed whether tea inactivates SARS-CoV-2 diluted in human saliva. Treatment of SARS-CoV-2 with 500 μM TFDG or TSA for 10 sec reduced the virus titer to undetectable levels (less than 1/1,000). Black and green tea decreased virus titer to less than 1/100 within 10 sec even in saliva. These findings suggest a possibility that intake of, or gargling with, tea may inactivate SARS-CoV-2 in saliva in infected individuals, which may eventually attenuate spread of COVID-19 within a population, although clinical studies are required to test this hypothesis by determining the intensity and duration of the anti-viral effect of tea in saliva in humans.

scholarly journals Rapid Inactivation In Vitro of SARS-CoV-2 in Saliva by Black Tea and Green Tea

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 721
Author(s):  
Eriko Ohgitani ◽  
Masaharu Shin-Ya ◽  
Masaki Ichitani ◽  
Makoto Kobayashi ◽  
Takanobu Takihara ◽  
...  
Keyword(s):  
Virus Infection ◽  
Green Tea ◽  
Virus Titer ◽  
Epigallocatechin Gallate ◽  
Black Tea ◽  
Human Saliva ◽  
Detectable Level ◽  
Healthy Human ◽  
Rapid Inactivation

Saliva plays major roles in the human-to-human transmission of SARS-CoV-2. If the virus in saliva in SARS-CoV-2-infected individuals can be rapidly and efficiently inactivated by a beverage, the ingestion of the beverage may attenuate the spread of virus infection within a population. Recently, we reported that SARS-CoV-2 was significantly inactivated by treatment with black tea, green tea, roasted green tea and oolong tea, as well as their constituents, (-) epigallocatechin gallate (EGCG), theasinensin A (TSA), and galloylated theaflavins. However, it remains unclear to what extent tea inactivates the virus present in saliva, because saliva contains various proteins, nitrogenous products, electrolytes, and so on, which could influence the antivirus effect of tea. Here, we assessed whether tea inactivated the SARS-CoV-2 which was added in human saliva. A virus was added in healthy human saliva in vitro, and after treatment with black tea or green tea, the infectivity of the virus was evaluated by TCID50 assays. The virus titer fell below the detectable level or less than 1/100 after treatment with black tea or green tea for 10 s. The black tea-treated virus less remarkably replicated in cells compared with the untreated virus. These findings suggest the possibility that the ingestion of tea may inactivate SARS-CoV-2 in saliva in infected individuals, although clinical studies are required to determine the intensity and duration of the anti-viral effect of tea in saliva in humans.

scholarly journals Significant inactivation of SARS-CoV-2 by a green tea catechin, a catechin-derivative and galloylated theaflavins in vitro

2020 ◽  
Author(s):  
Eriko Ohgitani ◽  
Masaharu Shin-Ya ◽  
Masaki Ichitani ◽  
Makoto Kobayashi ◽  
Takanobu Takihara ◽  
...  
Keyword(s):  
Green Tea ◽  
Untreated Control ◽  
Virus Titer ◽  
Epigallocatechin Gallate ◽  
Black Tea ◽  
The Novel ◽  
Undetectable Level ◽  
Green Tea Catechin ◽  
Novel Coronavirus

AbstractPotential effects of teas and their constituents on SARS-CoV-2 infection were studied in vitro. Infectivity of SARS-CoV-2 was significantly reduced by a treatment with green tea, roasted green tea or oolong tea. Most remarkably, exposure to black tea for 1 min decreased virus titer to an undetectable level (less than 1/1,000 of untreated control). An addition of (-) epigallocatechin gallate (EGCG) significantly inactivated SARS-CoV-2, while theasinensin A (TSA) and galloylated theaflavins including theaflavin 3, 3’-di-gallate (TFDG) had more remarkable anti-viral activities. Virus treated with TSA at 500 μM or TFDG at 100 μM showed less than 1/10,000 infectivity compared with untreated virus. TSA and TFDG significantly inhibited interaction between recombinant ACE2 and RGD of S protein. These results strongly suggest that EGCG, and more remarkably TSA and galloylated theaflavins, inactivate the novel coronavirus.

scholarly journals The modulatory effect of polyphenols from green tea, oolong tea and black tea on human intestinal microbiota in vitro

2017 ◽  
Vol 55 (1) ◽  
pp. 399-407 ◽  
Author(s):  
Hanyang Sun ◽  
Yuhui Chen ◽  
Mei Cheng ◽  
Xin Zhang ◽  
Xiaojie Zheng ◽  
...  
Keyword(s):  
Green Tea ◽  
Intestinal Microbiota ◽  
Black Tea ◽  
Oolong Tea ◽  
Human Intestinal Microbiota

scholarly journals Review: Telaah Kandungan Senyawa Katekin dan Epigalokatekin Galat (EGCG) sebagai Antioksidan pada Berbagai Jenis Teh

2021 ◽  
Vol 8 (1) ◽  
pp. 31
Author(s):  
Zahra Hasna Fadhilah ◽  
Farid Perdana ◽  
Raden Aldizal Mahendra Rizkio Syamsudin
Keyword(s):  
Antioxidant Activity ◽  
Green Tea ◽  
Bioactive Compounds ◽  
Bitter Taste ◽  
Epigallocatechin Gallate ◽  
Black Tea ◽  
Major Determinant ◽  
Oolong Tea ◽  
Ic50 Value ◽  
High Antioxidant Activity

Katekin merupakan senyawa bioaktif dengan kerangka flavan-3-ol dan menjadi senyawa utama penentu mutu serta dapat memberikan rasa pahit yang khas pada teh. Senyawa turunan katekin yang memiliki aktivitas sebagai antioksidan paling kuat dan melimpah yaitu epigalokatekin galat. Tujuan dari review artikel ini yaitu untuk mengetahui kandungan senyawa katekin dan epigalokatekin galat sebagai antioksidan pada berbagai jenis teh berdasarkan nilai IC50.Metode penulisan review artikel ini dilakukan dengan mencari serta menganalisis studi pustaka dari beberapa jurnal yang berkaitan dengan aktivitas antioksidan pada berbagai jenis teh dengan penelusuran terhadap senyawa katekin, khususnya epigalokatekin galat. Hasil review menunjukkan bahwa aktivitas antioksidan pada pengolahan jenis teh seperti teh hijau, teh oolong, dan teh hitam memiliki perbedaan yang cukup signifikan yang dapat dilihat dari kandungan senyawa katekin dan EGCG dimana semakin besar kandungan senyawa tersebut, maka aktivitas antioksidannya semakin tinggi. Selain itu, tingginya aktivitas antioksidan dapat dilihat dari nilai IC50. Semakin rendah nilai IC50, maka aktifitas antioksidan akan semakin tinggi. Teh hijau terbukti memiliki aktivitas antioksidan yang paling tinggi diantara teh lainnya dengan kandungan katekin sebesar 10,04% dan epigalokatekin galat sebesar 3,28% serta nilai IC50 yang paling rendah yaitu 58,61 µg/mL. Kata Kunci: Katekin, Teh Hijau, Teh Oolong, Teh Hitam, Antioksidan Catechins are bioactive compounds with a flavan-3-ol structure and become a major determinant of quality compounds and can give a distinctive bitter taste of tea. Catechin derivative compounds that have the antioxidant activity as the strongest and abundant are epigallocatechin gallate. The purpose of this article review was to determine the content of catechins and epigallocatechin gallate compounds as an antioxidant in various types of tea based on the IC50 value. The method of writing of this article review was carried out by searching and analyzing literature studies from several journals related to antioxidant activity in various types of tea by tracing catechin compounds, especially the epigallocatechin gallate. The results of the review showed that the antioxidant activity in the processing of types of tea such as green tea, oolong tea, and black tea has significant differences which could be seen from the content of catechins and EGCG compounds where the greater the content of the compounds, the higher the antioxidant activity. Also, the high antioxidant activity can be seen from the IC50 value. The lower the IC50 value, the higher the antioxidant activity. Green tea shows to have the highest antioxidant activity among other teas with a catechin content of 10.04% and an epigallocatechin gallate of 3.28% and the lowest IC50 value of 58.61 µg/mL.

scholarly journals Significant Inactivation of SARS-CoV-2 In Vitro by a Green Tea Catechin, a Catechin-Derivative, and Black Tea Galloylated Theaflavins

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3572
Author(s):  
Eriko Ohgitani ◽  
Masaharu Shin-Ya ◽  
Masaki Ichitani ◽  
Makoto Kobayashi ◽  
Takanobu Takihara ◽  
...  
Keyword(s):  
Green Tea ◽  
Epigallocatechin Gallate ◽  
Virus Production ◽  
Black Tea ◽  
Rna Replication ◽  
Viral Rna ◽  
The Novel ◽  
Green Tea Catechin ◽  
Novel Coronavirus

Potential effects of tea and its constituents on SARS-CoV-2 infection were assessed in vitro. Infectivity of SARS-CoV-2 was decreased to 1/100 to undetectable levels after a treatment with black tea, green tea, roasted green tea, or oolong tea for 1 min. An addition of (−) epigallocatechin gallate (EGCG) significantly inactivated SARS-CoV-2, while the same concentration of theasinensin A (TSA) and galloylated theaflavins including theaflavin 3,3′-di-O-gallate (TFDG) had more remarkable anti-viral activities. EGCG, TSA, and TFDG at 1 mM, 40 µM, and 60 µM, respectively, which are comparable to the concentrations of these compounds in tea beverages, significantly reduced infectivity of the virus, viral RNA replication in cells, and secondary virus production from the cells. EGCG, TSA, and TFDG significantly inhibited interaction between recombinant ACE2 and RBD of S protein. These results suggest potential usefulness of tea in prevention of person-to-person transmission of the novel coronavirus.

Green tea extract and its major component epigallocatechin gallate inhibits hepatitis B virus in vitro

2008 ◽  
Vol 78 (3) ◽  
pp. 242-249 ◽  
Author(s):  
Jun Xu ◽  
Jue Wang ◽  
Fei Deng ◽  
Zhihong Hu ◽  
Hualin Wang
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Green Tea ◽  
Epigallocatechin Gallate ◽  
Green Tea Extract ◽  
B Virus ◽  
Tea Extract

Immobilization and Characterization of Tannase and its Haze-removing

2009 ◽  
Vol 15 (6) ◽  
pp. 545-552 ◽  
Author(s):  
Erzheng Su ◽  
Tao Xia ◽  
Liping Gao ◽  
Qianying Dai ◽  
Zhengzhu Zhang
Keyword(s):  
Kinetic Parameter ◽  
High Activity ◽  
Green Tea ◽  
Storage Stability ◽  
Residual Activity ◽  
Black Tea ◽  
Optimum Temperature ◽  
Oolong Tea ◽  
Optimum Ph

Tannase was effectively immobilized on alginate by the method of crosslinking-entrapment-crosslinking with a high activity recovery of 76.6%. The properties of immobilized tannase were investigated. Its optimum temperature was determined to be 35 ° C, decreasing 10 °C compared with that of free enzyme, whereas the optimum pH of 5.0 did not change. The thermal and pH stabilities of immobilized tannase increased to some degree. The kinetic parameter, Km, for immobilized tannase was estimated to be 11.6 × 10-4 mol/L. Fe2+ and Mn2+ could activate the activity of immobilized tannase. The immobilized tannase was also applied to treat the tea beverage to investigate its haze-removing effect. The content of non-estern catechins in green tea, black tea and oolong tea increased by 52.17%, 12.94% and 8.83%, respectively. The content of estern catechins in green tea, oolong tea and black tea decreased by 20.0%, 16.68% and 5.04%, respectively. The anti-sediment effect of green tea infusion treated with immobilized tannase was significantly increased. The storage stability and reusability of the immobilized tannase were improved greatly, with 72.5% activity retention after stored for 42 days and 86.9% residual activity after repeatedly used for 30 times.

Determination of flavonol glycosides in green tea, oolong tea and black tea by UHPLC compared to HPLC

2015 ◽  
Vol 183 ◽  
pp. 30-35 ◽  
Author(s):  
Heyuan Jiang ◽  
Ulrich H. Engelhardt ◽  
Claudia Thräne ◽  
Beate Maiwald ◽  
Janina Stark
Keyword(s):  
Green Tea ◽  
Black Tea ◽  
Flavonol Glycosides ◽  
Oolong Tea

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

2021 ◽  
Vol 14 (1) ◽  
pp. 001-010
Author(s):  
Syamsu Nur ◽  
Andi Nur Aisyah ◽  
Alfat Fadri ◽  
Sharfianty ◽  
Amriani Sapra ◽  
...  
Keyword(s):  
Green Tea ◽  
Color Change ◽  
Black Tea ◽  
Processing Method ◽  
Uv Spectrophotometry ◽  
Uv Spectrum ◽  
Polyphenol Compounds ◽  
The Public ◽  
Chemical Reagents ◽  
Oolong Tea

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.

scholarly journals Green tea phytocompounds targets Lansterol 14-α demethylase against ergosterol biosynthesis in Candida glabrata

2021 ◽  
Vol 12 (3) ◽  
pp. 1793-1797
Author(s):  
Priyanka Sirari ◽  
Jigisha Anand ◽  
Devvret ◽  
Ashish Thapliyal ◽  
Nishant Rai
Keyword(s):  
Green Tea ◽  
Candida Glabrata ◽  
Scientific Evidence ◽  
Epigallocatechin Gallate ◽  
Ergosterol Biosynthesis ◽  
Epicatechin Gallate ◽  
P450 Monooxygenase ◽  
Antifungal Potential ◽  
Inhibitory Potential

Green tea is credited as one of the world’s healthiest drinks with enriched antioxidants. It is known for its multi-beneficial health benefits against diabetes, blood pressure, hypertension, gastro-intestinal upset and is bestowed with significant antimicrobial potential. There are previous scientific evidence highlighting the antifungal potential of green tea and has identified it as a potential inhibitor of non-albicans Candida species. Lansterol 14-α demethylase (Erg 11) or CYP51 protein belongs to the cytochrome P450 monooxygenase (CYP) superfamily. Erg 11 is involved in ergosterol biosynthesis and has a significant role in azole drug resistance in Candida glabrata. The present study attempted to identify the inhibitory potential of green tea phytocompounds against inhibition of Erg 11 in Candida glabrata using bioinformatics tool viz., autodock vina software. Out of 15 green tea phytocompounds investigated, the study identified, Rutin (-10.5 kcal) Kaempferitrin (-9.4kcal), Epigallocatechin gallate (-10kcal), Epicatechin gallate (-8.7kcal), and Coumaroylquinic acid (-8.6kcal) acid as the potent phytocompounds which showed significant molecular interaction with Erg 11 in Candida glabrata. In attribution to the constant emergence of azole-resistant isolates, this preliminary analysis therefore, indicated the potential of green tea phytocompounds against inhibition of non-albicans Candida specific candidiasis. However, further, in vitro antimicrobial efficacy of these phytocompounds, the dose regime, drug likeliness, and cytotoxic analysis are required to be investigated and validated.

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