Tea Seminar

7/31/2019 Tea Seminar

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Seminar on

L-THEANINE, A UNIQUE AMINO ACID IN

TEA

TABLE OF CONTENTS

1. INTRODUCTION ……………………………………………………….. 3

2. OBJECTIVE …………………………………………………...................7

3. STATES OF MATTER …………………………………………………. 7

4. BIOSYNTHESIS OF THEANINE AND ITS METABOLISM IN TEA

PLANT..........................................................................................................7

5. ENZYMIC SYNTHESIS OF THEANINE…………………………….....8

6.PHYSIOLOGICAL EFFECTS.....................................................................11

6.1 Alpha-brain activity……………………………………………………11

6.2Balancing sleep/wake…………………………………………………...12

6.3Balancing brain chemistry……………………………………………...13

6.4Balancing the liver: Alcohol…………………………………………….14

6.5Additional Benefits...................................................................................15

6.6Stress Relief ………………………………………………………………17

7.STATUS AND USAGE………………………………………………………..17

8.CONCLUSION………………………………………………………………...18

9. REFERENCES……………………………………………………………......19



1. Introduction

Tea is a natural beverage brewed from the leaves of an evergreen plant called

Camellia sinensis. While it has become common place for people to refer to any hot

beverage that is brewed from naturally occurring plants or plant extracts as "tea"

technically, those herbal hot beverages should be called "teassanes", as the word "tea"

is reserved for beverages brewed from leaves of Camellia sinensis.( H:\Premium Tea

From Highlands JAYA TEA.htm)

Tea is a stimulating and refreshing beverage (Swami Nathan 1987).

The beverage is prepared from the tea particles which are manufactured from

tender shoot of the plant. Tea plant is a kind of evergreen laurel tree and is

taxonomically classified as Camellia sinesis (L) O. Kuntze of the family of Theaceae

(Konwar, 1983).

The tea plant spontaneously grows widely from tropical to temperate region in

Asia and has been closely associated with people’s life (Chu, 1997).

One of the most important processes in tea manufacturing for drink is

fermentation. It is known that the conversion of tannin in tea is not achieved by

microorganisms but enzymes present in the leaves and show this phenomenon should

be called “enzymation”, exactly. The degree of fermentation greatly affects the quality

and type of tea. According to the degree of fermentation, tea is classified in three

groups:

i. Unfermented tea : Green tea

ii. Semi-fermented tea : Oolong and Pouchong tea

iii. Fully -fermented tea : Black tea (chu ,1997)

Chemical components of tea

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• Tea polyphenols

• Caffeine

• Amino acid and other nitrogenous compounds

• Vitamins

• Inorganic Elements

• Others

1. Carbohydrates

2. Lipids (Chu and juneja, 1997)

Chemical composition of fresh tea shoot is given below.

Compounds % Dry weight ContributionTotal polyphenols 25-30 Astringency

Flavanols

(-)Epigallocatechin gallate 8-12

(-)Epicatechin gallate 3-6

(-)Epigallo catechin 3-6

(-)Epicatechin 1-3

(+)Catechin 1-2

(+)Gallocatechin 3-4

Flavanols and flavonolglycosides

3-4

Leuco anthocyanins 2-3

Polyphenolic acids and depsides 3-4

Caffeine 3-4 Briskness

Theobromine 0.2

Theophylline 0.5

Amino acids 4-5 Brothyness

Organic acids 0.5-0.6Monosaccharide 4-5

Polysaccharides 14-22

Cellulose and hemicelluloses 4-7

Pectin 5-6

Lignin 5-6

Protein 14-17

Lipids 3-5

Chlorophylls and other pigments 0.5-0.6 Colour and appearance

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Ash (minerals) 5-6

Volatiles 0.01-0.02 Aroma

Source(H:\The Chemistry

of Tea.mht) www.google.com

A tea infusion provides only 4 cal. per cup but.with the addition of a table spoon of

milk (10 calories) and a lump of sugar (25 calories) , it provides about 40 calories. One

pound of good tea (.45 kg) may contain upto 245 grains (15.9gms) of caffeine and is

sufficient to make 200 cups of the beverage ( The New Encyclo., 1768).

Among the latest discoveries about tea is that it can prevent depression and lower

blood pressure. Both green and black tea has beneficial health effects, the main

difference being that black tea is oxidized. That would seem to destroy tea” bioactivity,

but it does not .Black tea continues to prove itself in scientific studies. Researchers with

the US Department of agriculture, for example, recently reported that five cup of black

tea a day can lower potentially harmful low –density lipoprotein (LDL) and total

cholesterol in people with mildly elevated cholesterol.(junejia,1999)

Black tea has benefits, but green tea has undergone more investigation,

especially in Japan, where it’s the most popular beverage .Many new reports have come

out about green tea “s amino acid, theanine, since life extension introduced it .The only

other known source of this amino acid is mushroom. Discovered in 1949, theanine

occupies a place on the shelf quite different from that of other dietary supplements. It

has to do with tea ceremony (H:/Green Tea)

L-theanine is a unique free (non-protein) amino acid because it is found only in

tea plant with the exception of mushroom and seedlings of few kinds of Camellia

species, Camellia Japonica and Camellia sasanqua. Theanine in tea leaf account about

50% of all free amino acids (Chu,kobayashi,Junejia and yamamoto1997).

The content of total nitrogen in green tea extracts ranges from 4.5to6%, andabout a half of it of free amino acid. Theanine and Glutamic acid are major amino acid

in green tea infusion, and aspartic acid and arginine are next (Chu and junejia, 1997).

The occurrence of theanine in tea leaves was discovered by Sakato in 1950, and its

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http://www.google.com/





chemical structure was determined to be γ -ethylamino-L-glutamic acid.

Fig; structure of L-theanine.

Theanine as well as glutamine has been known to act antagonistically against

paralysis induced by caffeine. Also, several chemical derivatives including theanine and

γ-amino butyric acid found in green tea have been reported to be physiologically active

substances.(chu,Kobayash,Junejia,and Yamamoto,1997)

Green tea content higher amount of L-theanine than other tea. In general green tea

infusion content 45.9% L-theanine of total free amino acid. Preparation of tea infusion:

100g of hot water was added to 100mg of ground dry tea leaves, and mixture was kept

at 80 degree Celsius for 30 minutes. (Chu and Juneja, 1997).

The content of amino acids in tea leaves harvested in season of early summer are

usually superior in quality to those harvested in latter season .Shading of the tea plant

increases the amount of amino acids, especially of theanine in young shoots, and

decreases the polyphenol content.

Table: Seasonal changes in some chemical component of green tea leaves.

Components (%)

Harvested in early

summer (%)

Harvested in late

summer (%)Soluble fraction 46.99 49.95

Polyphenol 10.89 14.85

Total nitrogen 5.31 4.52

Theanine(mgper 100g

leaves)

1,613 404

caffeine 3.07 3.48

Free amino acid 1.9- 3.2 0.5-1

(Chu, 1997)

Tea leaf is a sole natural resource of theanine reported to present .However recently the

production of theanine has become possible to be carried out in an industrial scale by

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the method of enzymic synthesis. It was also found that the intake of theanine brings

the generation of α-brain wave in human.

L –theanine is also one of the components that decide its taste (umami) (Chu,

kobayashi, Juneja, and Yamamoto).

2.OBJECTIVES

The main objectives of this class seminar are:

• To study the role of L-theanine present in tea.

• To study the antagonism action of L –theanine against the stimulating effect of

caffeine in brain.

• To the study the Anxiety reducing and mood enhancing property of L-theanine.

• To study the neurotransmitting character of L-theanine.

3.STATES OF MATTER

Tea showing the many health benefits but what makes it the most consumed

beverage in the world after water is its pleasant taste and relaxation effect. Both of these

qualities and more can be traced to a unique, neurologically active amino acid in tea

called L-theanine (gamma-ethyl-amino-Lglutamic acid).

L-theanine is a free (non-protein) amino acid found almost exclusively in tea

plants (camellia sp.), constituting between 1 and 2 percent of the dry weight of tea

leaves. It is the predominant amino acid in green tea leaves, giving tea its characteristic

umami or 5th taste (besides the four tastes namely sweet, salty, acid and bitter). Attempt

to isolate the L-theanine with its physiological benefits from the tea leaves were once

difficult, expensive and inefficient. Economically feasible method of producing the

identical L-theanine now exist and do not require a mountain of tea leaves.(H:\L-

theanine.mht)

4.BIOSYNTHESIS OF THEANINE AND ITS METABOLISM IN TEA PLANT.

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Theanine is synthesized in the root starting from ammonia as the nitrogen

source .The gultamic acid produced in the root conjugate with ethylamine by the

catalytic reaction of L-glutamate ethylamine ligase (E.C., 6.3.1.6).Ethylamine is

derived from alanine by decarboxylation or denoveo synthesis via pyruvic acid.

It is known that Camellia sinesis produces ethylamine from alanine. Theanine

synthesized in the root is immediately transferred to growing shoot and accumulated

there. A remarkable accumulation of theanine in buds and young leaves is due to the

continuous transport of it from roots, because the catabolism of theanine in young

shoots is slow relative to the transportation rate of theanine.

Theanine accumulated in young shoots is hydrolyzed into gulatmic acid and

ethylamine by an enzyme .The ethylamine produced is used to synthesize catecheine

under the sunlight .A part of ethylamine isdegarded into acetaldehyde, hydrogen

peroxide, and ammonia by an enzymic oxidation reaction. The released ammonia is

used as a nitrogen source again.

Fig 1: schematic representation of synthesis and metabolism of theanine in tea

plant. (chu, kobayashi,junejia,and Yamamoto,1997)

5. ENZYMIC SYNTHESIS OF THEANINE

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An enzymic synthetic method of theanine from glutamine and ethylamine was first

reported by Yamada and his coworkers in 1990, using gultaminase from Pseudomonas

nitroreducens.

P.nitroreducens IFO 12694 were immobilized with k-carragreenan (fig) and packed

into a series of cylindrical reactors (Fig-3.).Solution of 0.3M glutamine and 0.7M

ethanolamine in 0.05M borate- NaOH buffer (pH9.5) were mixed and immediately

supplied to the reactor at a flow rate of SV =0.33per hour at 30 oC.Bythis method

production of theanine was operated for over a period of 120days with a high yield of

the product (fig4).The theanine in the product reservoir was easily isolated by

subjecting the solution to column chromatography using an ion exchanger. The yield of

theanine was about 95percent based on glutamine consumed.

Fig 2: Preparation of Immobilized cells.

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(chu, kobayashi,junejia,and Yamamoto,1997)

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6. PHYSIOLOGICAL EFFECTS

The calming effect of green tea may seem contradictory to the stimulatory property of

tea’s caffeine content but it can be explained by the action of L-theanine. This amino

acid actually acts antagonistically against the stimulatory effect of caffeine on the

nervous system. Research on human volunteers has demonstrated that L-theanine

creates a sense of relaxation in approximately 30-40 min after ingestion via at least two

different mechanisms. First, this amino acid directly stimulates the production of α-

brain waves, creating a state of deep relaxation and mental alertness similar to what

achieved through meditation.

Second, L-theanine is involved in the formation of inhibitory neurotransmitter,

γ-amino-butyric acid (GABA). GABA influences the level of two other

neurotransmitters dopamine and serotonin, producing the key relaxation effect. (H:\L-

Theanine Unique Anxiety Reducer and Mood Enhancer Increases Alpha Waves and

Alertness.mht)

6.1. Alpha-brain activity

The brain emits weak electrical impulses (brain waves) that can be measured on

the surface of head .The predominant frequency of electrical impulses correlates with

different types of mental states and activities. Brain waves are classified into four

categories (delta, theta, alpha and beta) each with an associated mental state. Shown in

figure.

Fig 5: Classification of brain waves and mental conditions. (www.lipton.com

au/l theanine)

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Delta is seen only in the deepest stage of sleep. Theta is seen in light sleep and

drowsiness. Alpha is present in wakefulness where there is a relaxed and effortless

alertness and Beta is seen in highly stressful situation and where there is difficulty in

mental concentration and focus. It is well known that α-brain waves are generated

during a relaxed state and therefore alpha waves are used as an index of relaxation.

Fig 6: Changes in appearance of the α-brain wave. Differences in appearance and

strength of α-wave become clearer 40 min. after the intake of a theanine solution

{200mg/100ml water}

Figure shows a result obtained in the brain topography visualization by the

computer analyzing technique when theanine was orally administered to volunteers.

The α-brain waves were observed from the back to the top of person’s head (occipital

and parietal regions of the brain) within approximately 40 minutes after the subjects had

taken either 50 or 200mg of L-theanine. In a separate study, the intensity of α-wavewere determined to be dose dependent (with a 200mg dose showing a significant

increase over controls) and detectable after 30 minutes(chu, kobayashi,junejia,and

Yamamoto,1997)

6.2Balancing sleep/wake

In balancing sleep/wake using tea ceremony in a capsule. Relaxation, rejuvenation,

focuses. The tea ceremony energizes without draining, calms without putting to sleep,

and motivates without causing a jagged edge. Although tea can have as much or more

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caffeine than some coffees, it doesn’t have the “speedy” effect. The reason is its secret

ingredient, L-theanine. Research shows that l-theanine neutralizes the speedy, jagged,

bad effect of caffeine without reducing its mind –energizing, fat –burning features.

L-theanine’s effect on the brain can be visualized on an EEG. Brain waves are actually

smoothed out-but not flattened out – by supplemental L-theanine.the body is relaxed,

the mind is calmed, but no drowsiness occurs. This is exactly the type of relaxation

prescribed by sleep therapists. The person seeking help will be asked to listen to music

or engage in a similar relaxing activity immediately before retiring. Studies shows that

pre-sleep relaxation is very effective against insomnia, even in tough cases.

Falling asleep is one thing, staying asleep and quality sleep is another. Researcher in

Japan gave volunteers 200mg of L-theanine daily and recorded their sleep pattern on

devices worn around theirs wrists.theL-theanine didn’t cause the subject to sleep longer,

but it did cause to sleep better. It was documented that sleep quality, recovery from

exhaustion, and refresh feelings were all enhanced byL-theanine.those taking L-

theanine felt like they slept longer than they actual did. This is the good news for people

who don’t get enough sleep, or those who want to sleep less and do more.

One of the other effects of the tea ceremony is that it leaves people in better mood.

Knowing that L-theanine can cross the blood –brain barrier and positive affect brain

chemistry, scientist investigated its mood – modulating effects. The result of those

studies has led to L-theanine being patent as a mood Enhancer. How it works is not

completely understood, but one thing researchers have discovered is that L-theanine

changes levels of amino acids affecting serotonin and other neurotransmitters in the

brain.( http :/www raysahelian. Com/theanine. Html)

6.3Balancing brain chemistry

Memory impairment is frequently associated with old age or Alzheimer’s

disease, but there are other causes stress and depressions, for Eg. Cause memory loss.

Although usually thought of as mere psychological status, stress and depression causes

physical changes in body chemistry. The brain is notably affected.

Stressed hormone known as glucocorticoids are activated by both stress and

depression. In turn, they cause imbalance in brain chemistry that interfere with mood

and memory. The effect is bio chemical. Glucocorticoids disrupt serotonin, dopamine,

norepinephrine, and other brain chemical. These “neurotransmitters” are the target of

prescription antidepressants such as Prozac ® and wellbutrin ®.and it has been shown

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that glucocorticoids can interfere with ability of Prozac ® and other drugs to work.

Worse still, glucocorticoids can cause the brain to shrink. Counteracting glucocorticoids

extremely important.

Drugs that blocks glucocorticoids have been proposed as a treatment for

depression, and strangely enough, people have been treated successfully ketoconazole

(Nizoral®), an antifungal drug with side effect of suppressing glucocorticoids.

Theanine also suppresses glucocorticoids, and it is one of the few dietary supplements

that crush the blood brain-barrier.

Theanine’s connection to the suppression of glucocorticoids is through

glutamate. Researchers have discovered that this natural component of brain chemistry

which is not traditionally associated depression, in fact plays a major role. In people

who are depressed glutamate levels are out of balance. Preliminary studies show that

blocking certain signals in the brain activated by Glutamate may be as effective as

prescription anti-depressants. L-thenine may acts as an antagonist. Researchers believe

that glutamate receptor antagonists may offset the harmful effect of high

glucocorticoids levels and offer neuroprotective effects against both acute and chronic

neurodegenerative disease.

Glutamate-activated signals not only effects mood, they affects memory

and learning. Memory and learning are similar biochemical process in the brain. If an

animal can’t remember, it can’t learn. Stroke, Alzheimer’s disease, and alcohol all

causes memory loss involving disruption in glutamate-related signals that inhibit the

storage and retrieval of memories.

If theanine is present in the body at the time strokes occurs, the damaged area

will be significantly reduced. This is supported by a Chinese study, of 14000 people,

which found that drinking tea slashes the risk of stroke by 40%.maintaining healthy

level of L-theanine and other tea related compounds in the body may thus help prevent

memory loss and stroke-induced damaged brain tissue.

(http/www.supplementwatch.com./pipeline/doc.asp.)

6.4.Balancing the liver: Alcohol

Another part of the body that responds positively to theanine is the liver.

Research from Japan shows that theanine is a powerful antidote to the effects of

alcohol. If theanine is given to mice before or after they drink alcohol, it significantly

lowers blood levels of alcohol. It works by modulating alcohol chemistry.

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Alcohol is converted to a toxic chemical called acetaldehyde, which is similar to

formaldehyde and more toxic than alcohol itself. Theanine accelerates the break down

of acetaldehyde and blocks toxic radicals. The remarkable power of theanine to

intercept free radicals was demonstrated in the same study. It is not only blocked

radicals caused by alcohols; it suppressed levels to below normal for five hours.

One reason theanine is able to reverse damage caused by

alcohol is that it restores the level’s all purpose antioxidant and detoxifier known as

glutathione. Drinking alcohol causes significant suppression of this critical factor. If the

suppression is infrequent, the liver bounces back, if suppression is chronic, however,

the liver can’t overcome the stress. It breaks down and the effects are fell throughout

the body. Theanine helps counteract the alcohol-induced loss of glutathione.

Glutathione is not only something people who drink alcohol have to worry

about, it’s something that oncologists have to worry about. Depletion of glutathione in

vital organs like the heart is a major cause of chemotherapy toxicity. Because of it,

some drugs that could otherwise be useful in treating certain types of cancers can’t be

used. Researchers looking into the possibility of adding theanine to chemotherapy have

found that it counteracts drug – induced losses of glutathione in vital organs like the

heart, but not in tumors. In fact, it blocks tumors from getting glutathione, thus enabling

some type of chemotherapeutic drugs to work better. By enhancing glutathione where

it’s beneficial and reducing it where it’s not, theanine again shows its propensity to

restore balance(H:\Health benefit of tea.mht)

6.5Additional Benefits

L- theanine has a significant effect on the release or reduction of

neurotransmitters like dopamine and serotonin, resulting in improved memory and

learning ability. L-theanine may also influence emotions due to its effects on the

increased release of dopamine. L-theanine reduces brain serotonin concentration by

either curtailing serotonin synthesis increasing degradation in the brain.

The regulation of blood pressure is partly dependent upon catecholaminergic

and serotonergic neurons in both the brain and the peripheral nervous system. Studies

on spontaneously hypertensive rats (SHR) showed an impressive blood pressure

lowering effect with L-theanine. The lower blood pressure effect was dose- dependent

with the highest test dose creating the most significant drop. L-glutamine was used as

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one of the controls. Although L-glutamine is similar in chemical structure to L-

theanine, it did not exhibit an anti- hypertensive effect

Fig. 7: Reduction in blood pressure in hypertensive rats treated with L-

theanine(chu, kobayashi,junejia,and Yamamoto,1997)

Preliminary studies report that L-theanine has been found to increase the anti-

tumor activity of some chemotherapeutic agent (doxorubicin and idarubicin) and to

ameliorate some of the side effects of these drugs. It appears to increase the inhibitory

concentration of these drugs in the tumor cells, although the mechanism is not known.

At the same time, L-theanine decreased oxidative stress caused by these agents on the

normal cells, possibly due to mild oxidant activity. In this regard, L-theanine has been

shown to inhibit lipid peroxidation, catalyzed by copper, in low-density lipo-protein

(LDL) in vitro.(http:/www.biosynergy.com./theanine)

L-theanine may help the body’s immune system response when fighting

infection by boosting the disease- fighting capacity of gamma delta T cells. The study

published in 2003 by the Brigham and women’s Hospital, included a four week trial

with 11 coffee drinkers and 10 tea drinkers who consumed 600 ml of coffee or black

tea daily. Blood sample analysis found that the production of antibacterial proteins was

up to 5 times higher in the tea drinkers and indicator of a stronger immune response. .

(http:/www.biosynergy.com./theanine)

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An amino acid blend made up of 2000mg L-aspartic acid, 4000mg L-glutamine

and 300mg L-theanine can substantially increase our odds of having a Lucid dream.

(http/www.wikinow.com./lucid-dream)

6.6.Stress Relief

Stress and anxiety are debilitating conditions that upset the balance of our

hormones leading to a loss of our well-being, performance and even lifespan. Stress

impairs the immune system, leaving us vulnerable us vulnerable to opportunistic

infections, and can cause depression. In 1998, pharmaceutical sales of anti-anxiety

drugs totaled over 700 million dollars, while sales of antidepressants totaled close to 5

billion dollars! People under stress can mitigate many of the harmful effects of stress

with L-theanine without becoming sedated in the process. L-theanine doesn’t make one

drowsy, nor does it promote sleep because amino acid does not produce theta waves in

the brain. It should be noted that if an individual were already relaxed, taking L-

theanine would not produce further relaxation.(http:/www.biosynergy.com./theanine).

7.STATUS AND USAGE

L-theanine has just recently been introduced in U.S. market. Japan is credited

with most of the clinical studies and information we possess thus far on L-theanine but

research is ongoing. We do know that it is absorbed from the small intestine via a

sodium-coupled active transport process. It crosses the blood-brain barrier, as

evidenced by the mental effects. L-theanine competes for absorption in the intestinal

tract and the brain with the amino acids found in the methionine group (leucine,

isoleucine and valine), however the concentrations of amino acid are unchanged by

simultaneous ingestion of L-theanine.

L-theanine is extremely safe. There are no dietary limits on L-theanine intake

by the Japan Food Additive Association. In 1964, the Japanese Ministry of Health and

Welfare approved L-theanine for unlimited use in all foods, with exception of infant

food.

The intended use of L-theanine is that of a mental and physical relaxant that

does not induce drowsiness. Although there is no set schedule for taking L-theanine, it

may generally be taken at the first signs of stress. Based on the results of the clinical

studies, L-theanine is most effect in the range of 50-200 mg, with the effect being felt

within 30 minutes and lasting for 8-10 hours. Individuals with high stress levels may

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increase their dosage of L-theanine to at least 100mg, with no more than 600mg being

taken in hrs period. FDA recommends a maximum dose of 1200mg daily, although the

reason for this limit is not clear, due to its demonstrated safety. There are no known

adverse reactions to L-theanine and no drug interactions have been reported. L-theanine

is not affected by food and may be taken any time, as needed. Because it has a mild

taste, capsules may be opened and dissolved in water. Although it is probably safe for

pregnant women and nursing mothers. (http\www.web-Us.com.\L-theanine-anxiety-

reducer htm).

8.CONCLUSION

Research into L-theanine derived from the contradictory observation that green

tea, with its high caffeine content, produces a very calming effect. The seemingly multi-

dimensional reasons for this relaxation effect will continue to be studied. Current areas

of ongoing research include using L-theanine as an alternative to Ritalin in children and

adults, as a treatment for PMS, in controlling certain conditions of high blood pressure,

in sharpening mental acuity and concentration, and as an anti-cancer agent alone and in

synergy with other cancer-fighting agents. L-theanine may find another area of

application for its use as a supplement in reducing the negative side effects of caffeine

brought on by the over-consumption of coffee, soft drinks, or other caffeine-containing

substances and hence, drinking tea improve health by using 50-200mg L-theanine per

day.In other words ,L-theanine is a unique amino acid in tea to show interesting

physiological functions.

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Tea Seminar

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