Experimental Study On The Effect Of Pu’er Tea Aqueous Extract On Sleep

Objective:Pu’er tea extract is a well-known consumed beverage in china.Pu’er tea extract,with the large leaves of Camellia sinensis var(Pu-erh City,Yunnan,China.)as the raw material,was a health beverage which was processed by multiple procedures,including fixation,rolling,sun drying,and postfermentation.The distinctive flavor of Pu’er tea extract is formed after undergoing a series of complex changes in chemicals during post-fermentation,which also lead to its multiple health-promoting effects.The health benefits of Pu’er tea extract are mainly associated with its active components.Chemical studies revealed that its maj or active constituents were tea polyphenols,amino acids,tea alkaloids,tea pigments,organic acids,tea saponin,tea polysaccharide,etc.Pharmacological studies have shown that Pu’er tea extract possessed antidiabetic,antihypertensive,anticancer,Anti-fatigue,antiarteriosclerotic and other activities.However,the influence of Pu’er tea extract on sleep have not been reported.Previous studies have demonstrated that alkaloids(caffeine,theophylline and theobromine)of tea exhibits stimulant effects on the central nervous system.caffeine,as the main component of alkaloids,which is one of the most widely used psychoactive substances.caffeine intake is a common cause of sleep disruption.there are many reports showed that drinking tea can reduce drowsiness and fatigue such as green tea etc.In addition to the alkaloids,Pu’er tea extract contain theanine,a unique non-protein amino acid present in tea.The a nine has various beneficial physiological effects such as promoting relaxation,decreasing alertness,antistress effects and inhibiting the negative effects of caffeine on sleep.Theanine contents significantly decreased and caffeine content is constant during the fermentation Procedure of Pu’er tea extract,Pu’er tea extract provide doses of caffeine sufficient to induce a marked alertness and psychomotor activation,However,Survey shows that drinking Pu’er tea extract is less stimulating and more relaxing than drinking other teas.Therefore,wether other components from Pu’er tea extract inhibit the absorption or accelerate the metabolism of caffeine or not,the phenomenon of Pu’er tea extract exhibits less stimulant effects on the central nervous system afford for thought.Therefore,to elucidate the influence of Pu’er tea extract on sleep,pharmacodynamics of Pu’er tea extract and pharmacokinetics of caffeine in mice were investigated.Methods:To clarify the influence of Pu’er tea extract on sleep,pharmacodynamics of Pu’er tea extract and pharmacokinetics of caffeine in mice were investigated.(1)The HPLC method was developed in this paper for the quantification of caffeine of Pu’er tea extract.(2)ICR mice were randomly divided into different groups,including saline group(negative control),estazolam group(positive control),pu’er tea extract group,caffeine monomer group.Orally administered once a day for consecutive 14 days.Animal behavior from different groups were compared and analyzed to assess the pharmacodynamic of Pu’er tea extract.(3)Based on the application of H P L C analysis technology,the studies were developed in this paper for the quantification of caffeine.Also,the linearity,precision,accuracy,recovery rate,stability,repeatability,etc,were investigated for the method.The plasma concentration of caffeine from pu;er tea extract and caffeine monomer group s were measured by HPLC and the pharmacokinetic parameters were calculated with DAS 3.0 software.Results:(1)The HPLC method was established and successfully applied to the content determination of caffeine in Pu’er tea extract,the results showed that Pu’er tea extract contained 2.4%caffeine.(2)Pharmacodynamic results showed that caffeine monomer group has significantly enhanced the locomotor activity(p<0.05),reduced the probability of sleeping,prolonged sleep latency and induced sleeping time of the mice comparied with the saline group(p<0.01).The difference between Pu’er tea extract and saline groups in the locomotor activity,the probability of sleeping,sleep latency and sleeping time was not significant(p>0.05).(3)In this study,the sensitive,specific and rapid HPLC methods were established and their specificity,precision,accuracy,extraction rate and stability all meet the requirements of the analysis.The method was successfully applied to pharmacokinetic study for caffeine.Pharmacokinetic results indicated that the plasma concentration of caffeine after feeding Pu’er tea extract was less than that after oral administration caffeine monomer,and the maximum plasma concentrations of the two groups had significant difference(p<0.05).This phenomenon indicates that the Pu’er tea extract may produce some material to antagonize effect of caffeine.However,further research is needed to support the hypothesis.Conclusion:In Asian countries like China and India,tea drinking is a ritual and a life style.In recent years,with the spread of tea culture in the world,Pu’er tea extract have a good reputation among consumers.However,as the pace of people’s life is speeding up,their living presure is also getting higher,people sometimes suffer a lot to have a comfortable sleep.Survey shows that 10-15%of the adult populations suffer from chronic insomnia and an additional 25-35%with transient or occasional insomnia.The traditional consumption concept of "tea can be refreshing" make people worry about drinking Pu’er tea extract can affect their sleep.therefore,the effects studying of Pu’er tea extract on sleep becomes imminent.Therefore,This paper had clarified the influence of Pu’er tea extract on sleep.Results showed that drinking Pu’er tea extract had no significant effect on sleep.The studying provided a useful reference for consumers of drinking Pu’er tea extract.