Tea as the most consumed beverage in the world has received enormous attention for its promoting health benefits.The deleterious effect ofα-dicarbonyls and AGEs formed in Maillard reaction is also a longterm challeng...Tea as the most consumed beverage in the world has received enormous attention for its promoting health benefits.The deleterious effect ofα-dicarbonyls and AGEs formed in Maillard reaction is also a longterm challenge.The connection between the two topics was the main aim of this review,to address and update the antiglycation effect and mechanism of tea and tea polyphenols.By analyzing recent publications,we have covered across chemistry models,cell lines and animal studies.Tea polyphenols,particularly catechins,showed outstanding antiglycation effect by trappingα-dicarbonyl compounds and impeding AGEs formation.Reduction of carbonyl stress brought alleviation to aging,diabetes,and collagen related diseases or complications through regulation of RAGE expression and subsequent MAPK and TGF-βpathway.Therefore,tea polyphenols can serve as promising natural candidates in the treatment and/or prevention of nephropathy,retinopathy,hepatopathy,hyperglycemia and obesity among others,by their potent antiglycation effect.Further studies need to address on aspects like exact mechanisms,solution of detection obstacles,balance of practical usage and harmful effects such as potential flavor damage and toxicity in food,to gain a comprehensive understanding of antiglycation activities of tea polyphenols and its actual application.展开更多
Effects of tannic acid on active aluminum species distribution in different pH tea soils in Yunnan and Jiangxi tea gardens were studied by field observation and laboratory analysis.There were 4 species of active alumi...Effects of tannic acid on active aluminum species distribution in different pH tea soils in Yunnan and Jiangxi tea gardens were studied by field observation and laboratory analysis.There were 4 species of active aluminum in the tea soil,i.e.,exchangeable aluminum Al3 +,unimer hydroxyl aluminum Al(OH)2 +Al(OH)+2,acid-soluble aluminum Al(OH)03and humic-acid aluminum Al-HA.Experimental results showed that tannic acid at levels 0 ~0.4 mmol/kg and 0 ~ 2.0 mmol/kg,with the rising of soil pH value,the content of exchangeable aluminum decreased significantly,hydroxyl aluminum,acid-soluble aluminum and humic-acid aluminum were increased gently.When the concentration of tannic acid increased to above 2.0 mmol/kg,the inhibition of higher concentration of tannic acid on content of active aluminum was strengthened with the rising of soil pH value and variation law of 20 ~ 40 cm soil layer was similar to 0 ~ 20cm soil layer.Generally speaking,the content of active aluminum in upper layer of soil were more than subsoil and total content of active aluminum in Yunnan tea soils were higher than Jiangxi tea soils.The correlation analysis showed that the soil pH were positively correlated with hydroxyl aluminum,humic-acid aluminum,pHBC(r = 0.796,0.960,0.852;p < 0.01,0.01,0.01) in 0 ~ 20cm soil layer.pHBC were significant negative correlated with exchangeable aluminum(r =- 904,p < 0.01),hydroxyl aluminum(r =- 645,p < 0.05),and with humic-acid aluminum have a positive correlation,correlation coefficient was0.795(P < 0.05).Meanwhile,the tannic acid addition concentration were 0 ~ 0.4 mmol/kg soils pH were increased significantly,while samples attains a peak pH value afterwards decrease continuously,the relationship between the pH and the concentration of tannic acids accords with the equation:Y pH=- 0.04C DN+3.82(R2= 0.95,P < 0.01).When the concentration of tannic acid up to about 8.0 ~ 12.0 mmol/kg,soil pH keep unchanged.Therefore,we can clearly draw that effects of tannic acid on active aluminum content of the inflection point is not the same in different region of tea garden soil.Low concentration tannic acid can improve the soil content of various forms of aluminum,but with the increase in the amount of tannic acid,the various forms of aluminum content are inhibited.With the soil pH increased,high concentrations tannic acid on the inhibition of the release of active aluminum increased.pH and tannic acid on the total amount of active aluminum garden soil was mutual weakening effect relationship.展开更多
The recent research achievements about the mechanisms of beneficial health effects of tea polyphenols and the epidemiological investigation on anti-cancer,anti-cardiovascular diseases,and anti-obesity through tea cons...The recent research achievements about the mechanisms of beneficial health effects of tea polyphenols and the epidemiological investigation on anti-cancer,anti-cardiovascular diseases,and anti-obesity through tea consumption were reviewed.It is proved that reactive oxygen species is the main reason to induce cell mutation,DNA damage,obesity,high blood pressure and many kinds of cancers.Tea catechins and theaflavins have excellent bioactivity on scavenging ROS due to their characteristic structure feature of phenolic hydroxyl group,which means drinking tea could prevent diseases.Epidemidogical investigations also showed that tea consumption could reduce the risk of lung cancer,gastric cancer,bladder cancer,and so on.However,the frequency of tea drinking or tea consumption amounts significantly affected the prevention efficiency.The epidemiologic investigations also find that drink green tea,especial black tea is useful to modify the cardiovascular diseases.In vivo and vitro tests showed that tea supplement could moderate the metabolism of blood lipid and prevent obesity.These indicated that tea and tea extracts might reduce the risk of many diseases.展开更多
基金funded by Hubei Science and Technology Plan Key Project(G2019ABA100)。
文摘Tea as the most consumed beverage in the world has received enormous attention for its promoting health benefits.The deleterious effect ofα-dicarbonyls and AGEs formed in Maillard reaction is also a longterm challenge.The connection between the two topics was the main aim of this review,to address and update the antiglycation effect and mechanism of tea and tea polyphenols.By analyzing recent publications,we have covered across chemistry models,cell lines and animal studies.Tea polyphenols,particularly catechins,showed outstanding antiglycation effect by trappingα-dicarbonyl compounds and impeding AGEs formation.Reduction of carbonyl stress brought alleviation to aging,diabetes,and collagen related diseases or complications through regulation of RAGE expression and subsequent MAPK and TGF-βpathway.Therefore,tea polyphenols can serve as promising natural candidates in the treatment and/or prevention of nephropathy,retinopathy,hepatopathy,hyperglycemia and obesity among others,by their potent antiglycation effect.Further studies need to address on aspects like exact mechanisms,solution of detection obstacles,balance of practical usage and harmful effects such as potential flavor damage and toxicity in food,to gain a comprehensive understanding of antiglycation activities of tea polyphenols and its actual application.
文摘Effects of tannic acid on active aluminum species distribution in different pH tea soils in Yunnan and Jiangxi tea gardens were studied by field observation and laboratory analysis.There were 4 species of active aluminum in the tea soil,i.e.,exchangeable aluminum Al3 +,unimer hydroxyl aluminum Al(OH)2 +Al(OH)+2,acid-soluble aluminum Al(OH)03and humic-acid aluminum Al-HA.Experimental results showed that tannic acid at levels 0 ~0.4 mmol/kg and 0 ~ 2.0 mmol/kg,with the rising of soil pH value,the content of exchangeable aluminum decreased significantly,hydroxyl aluminum,acid-soluble aluminum and humic-acid aluminum were increased gently.When the concentration of tannic acid increased to above 2.0 mmol/kg,the inhibition of higher concentration of tannic acid on content of active aluminum was strengthened with the rising of soil pH value and variation law of 20 ~ 40 cm soil layer was similar to 0 ~ 20cm soil layer.Generally speaking,the content of active aluminum in upper layer of soil were more than subsoil and total content of active aluminum in Yunnan tea soils were higher than Jiangxi tea soils.The correlation analysis showed that the soil pH were positively correlated with hydroxyl aluminum,humic-acid aluminum,pHBC(r = 0.796,0.960,0.852;p < 0.01,0.01,0.01) in 0 ~ 20cm soil layer.pHBC were significant negative correlated with exchangeable aluminum(r =- 904,p < 0.01),hydroxyl aluminum(r =- 645,p < 0.05),and with humic-acid aluminum have a positive correlation,correlation coefficient was0.795(P < 0.05).Meanwhile,the tannic acid addition concentration were 0 ~ 0.4 mmol/kg soils pH were increased significantly,while samples attains a peak pH value afterwards decrease continuously,the relationship between the pH and the concentration of tannic acids accords with the equation:Y pH=- 0.04C DN+3.82(R2= 0.95,P < 0.01).When the concentration of tannic acid up to about 8.0 ~ 12.0 mmol/kg,soil pH keep unchanged.Therefore,we can clearly draw that effects of tannic acid on active aluminum content of the inflection point is not the same in different region of tea garden soil.Low concentration tannic acid can improve the soil content of various forms of aluminum,but with the increase in the amount of tannic acid,the various forms of aluminum content are inhibited.With the soil pH increased,high concentrations tannic acid on the inhibition of the release of active aluminum increased.pH and tannic acid on the total amount of active aluminum garden soil was mutual weakening effect relationship.
基金supported by a research grant of Philips "Brain-Bridge Plan"
文摘The recent research achievements about the mechanisms of beneficial health effects of tea polyphenols and the epidemiological investigation on anti-cancer,anti-cardiovascular diseases,and anti-obesity through tea consumption were reviewed.It is proved that reactive oxygen species is the main reason to induce cell mutation,DNA damage,obesity,high blood pressure and many kinds of cancers.Tea catechins and theaflavins have excellent bioactivity on scavenging ROS due to their characteristic structure feature of phenolic hydroxyl group,which means drinking tea could prevent diseases.Epidemidogical investigations also showed that tea consumption could reduce the risk of lung cancer,gastric cancer,bladder cancer,and so on.However,the frequency of tea drinking or tea consumption amounts significantly affected the prevention efficiency.The epidemiologic investigations also find that drink green tea,especial black tea is useful to modify the cardiovascular diseases.In vivo and vitro tests showed that tea supplement could moderate the metabolism of blood lipid and prevent obesity.These indicated that tea and tea extracts might reduce the risk of many diseases.
