FACULTY OF SCIENCE AND TECHNOLOGY

SEMESTER I, ACADEMIC SESSION 2014/2015

HONOURS SEMINAR

SCS 4901

THE BENEFITS OF GREEN TEA POLYPHENOLS IN CHEMICAL AND

ISLAMIC PERSPECTIVES

NAMES : NAJWA BINTI MOHAMED 1132220

: MASRURAH BINTI A. YAZID 1132242

: NUR IZZATI BINTI JAFFERY 1132244

: NUR ‘AFINI BINTI ISMAIL 1132245

: NUR SYAZWANI BINTI JAMIL 1132246

SUPERVISOR : ASSOC. PROF. DR. SALINA MAT RADZI

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ABSTRACT

Green tea (Camellia sinensis Theaceae) extracts nowadays is highly favor

among manufacturers for natural preservative instead of using paraben. This

is due to the chemical composition in tea leaf and most of them act as active

antioxidant. Polyphenols compose almost one-fourth in tea leaf and its group

for instant catechin possess a very high antioxidant properties. EGCG

(epigallocatechin-3-gallate) and epicatechin-3-gallate (ECG) in catechin are

some active antioxidant while flavonols which exist in flavonoid is a very

powerful antioxidant. Aside from that, the antioxidant activities are influenced

by the chemical structure of the flavonoids where the effectiveness of

antioxidant activity varies in different structure. In addition, other constituents

such as caffeine, theanine, vitamins and minerals also have its own functions

and advantages which contribute to the miracle of the green tea leaf. As a

powerful antioxidant and free radical scavengers, polyphenols give lots of

benefits in solving health problem such as obesity, oral health problems and

diabetes. Apart from that, from Islamic perspective, muslims’ scholar such as

Ibn Sina already mentioned that nature or green plant was preferred to be

used as remedies rather than using artificial to treat illness obeying on

Prophet Muhammad’s word who said that every disease has its cure and Allah

create everything in this earth to benefit human being.

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TABLES OF CONTENT

CONTENTS PAGES

ABSTRACT i 1.0 Introduction 1 2.0 Literature Review 3 2.1 Chemical Perspectives of Green Tea Polyphenol 3 2.1.1 The Chemical Constituents of Green Tea Extract

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- Catechin 3 - Other Polyphenols 4 - Caffeine 5 - Theanine 5 - Vitamins and Minerals 5 2.1.2 Benefits of Green Tea Polyphenols 5 - Polyphenols as a Powerful Antioxidant 5 - Anti-Obesity 6 - Promote Oral Health 7 - Anti-Diabetic 7 2.2 Islamic Perspectives of Green Tea Polyphenols 8 2.2.1 Al-Quran 8 - The Green Plant in Al-Quran 8 - The Origin of Variety Plant 8 2.2.2 Hadith 9 - Every Disease Has It Cure 9 - Treatment of Any Diseases Need Efforts to Recover

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2.2.3 Islamic Philosophy 10 3.0 Conclusion 11 4.0 References 12

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CHAPTER I

INTRODUCTION

Pharmaceutical study already exists for the past few centuries. It begins to

develop during Greek ancient and became well-known during Arabic ancient.

During Greek contribution, Hippocrates (469-373BC) wrote a book about

medical healing art which was Hippocratic Corpus and followed by De Meteria

medica, work of Pedanius Diosscorides, described about nearly 600 plants

and a 1000 simple drugs (Hamarneh,1969).

In Islamic pharmaceutical activities, it was based on rational, empirical,

sanitary and practical which they reflected back to the Prophet whereas he

once said that “For every disease there is remedy”. The early pioneer in this

field was Al-Damashqi who treated the successor and son of second caliph of

Abbasid, Harun al-Rashid. Ar-Razi once said that the pharmacist is a

specialist in a branch of knowledge closely associated with medicine

(Hamarneh,1969).There were also various other Islamic scholars along with

their excellent works that gives a great impact in pharmaceutical sector such

as Ibn Sina (Avicenna) ;Al Qanun Fi-Tibb and Al-Biruni ;Al-Saydala-Fi-Tibb.

However, it did not last longer when decline occurred which reflected the

stagnation and gradual deterioration of the whole Islamic nation (Amira Ayad,

2014).

Meanwhile, the discovery of green tea (Camellia sinensis theaceae) was

already found in China in early 3000 BC and it was brought to Japan by a

Buddhist priests. Aside from that, in eighth century, the discovery of method to

inhibit oxidation from green tea via steaming was discovered. According to

Rivenburg (2001), he stated that green tea has apparently become the official

drink of the war in Afghanistan. Afghan green tea slightly differ from Japanese

as it usually add cardamon,a spice from the ginger family. Moreover, green

tea had its own benefits such as improving blood flow, help stabilize blood

sugar in body and good for brain. A research study in 2013 found that green

tea helped to prevent heart related disease such as high blood pressure.

Few years ago, after several researches have been conducted, paraben has

been largely replaced formaldehyde as a preservative due to the low cost and

the effectiveness. However, in response to customer concerns, many brands

have started to manufacture and label paraben-free products, including

lotions, lipsticks, shampoos, scrubs, and other cosmetic products. However, in

2004, Philippa Dabre and her co-workers had detected parabens in 18 of 20

samples of tissue from breast tumor biopsies. It was proven that the estrogen

exposure linked to breast cancer development and progression. Other studies

had also confirmed that the alkyl esters of p-hydroxybenzoic acid (parabens)

can indeed be absorbed systemically in human as intact esters from direct

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application of parabens in cosmetic creams (Janjua et al., 2007,2008).

However, the U.S. Food and Administration and The World Health

Organization have been considered these chemicals as safe if they are at low

levels. To avoid any displeasure, most manufacturers have tried to use natural

preservative such as green tea extract to replace paraben. Two recent studies

in Japanase woman diagnosed with breast cancer have observed increased

green tea consumption to be inversely associated with breast cancer

recurrence (Inoue et al., 2001).

Concerning to the facts mentioned, this paper review will discuss on the

effectiveness of green tea polyphenols as the suggested preservative to

replace paraben in cosmetic products. In addition, this review also covers the

scientific signs of green tea in Islamic perspective to explore the magnificent

of Al-Quran, Hadith and Islamic philosophy in understanding the existence

and benefit of green tea.

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CHAPTER II

LITERATURE REVIEW

2.1 Chemical Perspectives of Green Tea Polyphenol

2.1.1 The Chemical Constituents of Green Tea Extract

Chemical composition of green tea leaves has been well studied and

documented. The polyphenols in tea leaf is chemical compounds that

constitute the most important group which is 25-35%. The reason why

polyphenols is the most important chemical compound in green tea leaf is

because they contain the family of flavonoids with antioxidant properties

known as catechins. According to Graham, the fresh green tea leaves contain

approximately 3.5% of caffeine, lignin is 6.5%, theanine is 4%, amino acids is

1-5.5%, organic acid is 1.5%, theobromine is 0.15-0.2%, theophylline and

other methylxanthines are 0.02-0.04%. Besides, there are another component

including phenolic acids, carbohydrates, minerals, enzymes, vitamins,

depsides and flavones (Chaturvedula & Parkash, 2011).

Catechin

The catechins are colorless, astringent and water soluble compounds.

Catechins possess two structure of benzene rings; A-rings and B-rings.

Besides, it contains C-rings which is a dihydropyran heterocycle attached to

hydroxyl –OH group on carbon C. In addition, it has four diastreoisomers as

the catechin molecule consists of two chiral centers located on carbon-2 and

carbon-3. Hence, the presence of two isomers in trans and two in cis

configuration are referred to catechin and epicatechin respectively. These

structures present to be important for antioxidant activities of green tea

polyphenols.

There are many chemical structures that influenced the antioxidant activity of

flavonoids. Firstly, the position of the hydroxyl groups in the molecules will

affect the antioxidant activity. Next, the presence of unsaturation, 4-oxo group

in C-ring and catechol structure in B-ring can increase the antioxidant activity

of flavonoids. The structure of 2,3-double bond and 4-oxo group in C-ring can

cause the delocalization of electron from B-ring attributed to the antioxidant

activity of flavonoids (Farkas et al., 2004). Catechins are predominant active

components, where epigallocatechin-3-gallate (EGCG) and epicatechin-3-

gallate (ECG) are the most effective antioxidants compounds. Epicatechin

(EC) and epigallocatechin (EGC) are the additional active compounds of

green tea extract. Scheme 1 shows the chemical structures of major catechins

in green tea extract. Catechins are characterized by various hydroxyl groups

on the A- and B-rings (Velayutham et al., 2008)

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Scheme 1: Chemical structures of major catechins in green tea extract.

According to Scheme 1, epicatechin structure (EC) ortho-3,4-dihydroxyl group

has presence in the B-ring while the present of three hydroxyl groups in the B-

ring is known as epigallocatechin (EGC) which is slightly different from

epicatechin (EC). Next, the additional of gallate group at carbon-3 in the C-

ring shows the structure of epicatechin gallate (ECG). In epigallogatechin

gallate (EGCG), it has three hydroxyl groups located at carbon-3,-4 and -5 on

B-ring and gallate group at carbon-3 of the C-ring (Yilmaz, 2006).

Other Polyphenols

About 7-14% of dried leaves contain other flavonoids compound. Two third of

these flavonoids are flavonols. It occurs in free state and glycosides of

glucose, rhomnose and other possibly sugars. Flavonols are the powerful

antioxidant known as anti-histamine and antioxidant with analogous structures

but represent a different type of oxidation state. The other example of

flavonols that be found in the green tea extract are quercetin, kaempferol and

myricitin (Del Rio et al., 2004). The uniqueness of tea is the presence of 2-3%

of theogallin. As shown in Scheme 2, theogallin is the derivation from gallic

and quinics acid.

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Scheme 2: Theogallin

Theogallin (3-galloylquinic acid) is produced by condensation of gallic acid

and (5R)-hydroxy group of quinic acid. In addition, it also contains depsides

which are condensation products from two different hydroxyl acids;

chlorogenic acid and p-coumarylquinic acids (Wickremasinghe, 1978).

Caffeine

Caffeine is a plant alkaloid found usually in coffee, tea and cocoa. The amount

of caffeine presence in tea is 2.5-4.5% and very small amount of other methyl

xanthine. Theobromine (0.1%) and theophylline (0.02%) are other methyl

xanthine present in green tea polyphenol (Borse et al., 2002).

Theanine

Non-protein of amino acid also present in this tea leaf known as theanine. Tea

leaf contains 4-6% of theanine which is an N-methylated derivative of

glutamine. It constitutes about half from the total of amino acid content. Its

presence in green tea can give the characteristics flavor which is good for

quality of beverage. Theanine tastes sweet and fresh while catechins and

caffeine give the taste of bitter and astringent. Next, alanine, arginine, serine

and asparagine are the example of amino acid presence in green tea.

However in Japanese green tea, theanine give 70% of the umami taste

(Kaneko et al., 2006).

Vitamins and Minerals

There are several Vitamin B and Vitamin C presence in tea polyphenols. The

studies have been studied to determine the level of minerals in green tea.

About 6% to 8% composition of minerals present in green tea such as

manganese, fluoride and aluminium. According to Simpson (2001), about 34%

of fluoride from green tea is an effective way to prevent dental cavity. Next,

manganese intakes are essentials nutrients required for metabolism in our

body (Cabrera et al., 2003).

2.1.2 Benefits of Green Tea Polyphenols

Polyphenol as a powerful antioxidant

Nowadays, the use of green tea as a potent source of beneficial antioxidant

has become widespread. According to Ahmad et al. (2014), polyphenols are

powerful antioxidants and free radical scavengers. They are strong

scavengers of superoxide, hydrogen peroxide, hydroxyl radicals, and nitric

oxide (NO) produced by various chemicals. Both of the oxidation and free

radical process will cause harm and damages to human body. Free radicals

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are unstable and it will attack all kinds of molecules that exist in the body such

as lipids, nucleic acids and protein. The damage caused by the free radical

may become irreversible and lead to certain diseases.

The effects of free radical are:

Acceleration of the ageing process

Inflammation of the joints(arthritis)

Increased risk of coronary heart disease

Deterioration of the eye lens

Risk of nerve cell damage

An antioxidant is a molecule stable enough to donate an electron to a

rampaging free radical and neutralize it. Thus reducing its capacity damage

(Labo et al., 2010). It will acts as an inhibitor to prevent vital molecules in

human body from damage. Polyphenols, which are widely distributed in

plants, are among the most studied natural anti-oxidants due to consumer

preference for natural products (Marta et al., 2015). The polyphenol

antioxidant will protect cells and body against some common health problem

and damage caused by free radicals.

Anti-obesity

Obesity is a metabolic disorder resulting from imbalance between energy

intake and energy expenditure (Sharangi, 2009).It is known to be a strong

contributor factor for lifestyle-related diseases. In the recent year studies

shown that green tea consumption may lead to anti-obesity. A related

investigation was conducted by Murase et al. (2006) regarding the effects of

long-term intake of tea catechins in combination with regular exercise on the

development of obesity in C57BL/6 mice. From the finding, an intake of tea

catechin together with regular exercise helps to reduce diet-induced obesity.

This bioactive substance attributed to the activation of whole-body

metabolism.

The other active compound constituted in green tea that increases the fat

burning is caffeine. It is well known stimulant that aid fat burning and improve

exercise performance. Moreover, ECGC (Epigalocatechin gallate), is a

substance that can boost metabolism and lead to anti-obesity. In conclusion,

the consumption of green tea may help reduce body weight, mainly the body

fat, by increasing postprandial thermogenesis and fat oxidation (Boschmann &

Thielecke, 2007). It increases fat burning and burn more calories which result

in reducing diseases risk and may lead a healthier life.

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Promote oral health

Tooth decay, plaque, cavity, gum problems and halitosis are among the oral

health problems. A research made by the American Dental Association (2013)

have mentioned that the bacteria in plaque produce acids that can cause the

enamel or root surface to break down. Plaque that remains or not removed

from teeth may irritate gums and may result in gingivitis and periodontist.

According to the American Dental Association (2013), the several symptom of

tooth decay are;

food trapped frequently between teeth;

discomfort or pain in or around your mouth;

difficulty biting down on certain foods;

sensitivity to hot, cold or even sweet foods;

bad breath;

white then later dark, spots on your teeth.

The plaque and cavities built-up can be prevent or reduce by regularly

consumption of green tea. Moreover, the consumption of green tea inhabits

bacteria growth that may cause a serious oral health problem. The chemical

composition contains in green tea is appear to inhibit the growth of bacteria.

Catechins in green tea are a chemical compound that responsible to inhibit

growth of the bacteria. It control inflammation and fight bacterial infection.

Fluoride is a chemical substance extracted by the tea plant in the soil which

result in accumulated in its leaves. It is a well know substance that frequently

used in producing an oral health based product such as toothpaste and

mouthwash. Therefore, tea is a very rich source of fluoride and one cup of tea

may contain between 0.3 mg and 0.5 mg of fluoride (Sharangi, 2009). It has

strong binding ability to enamel particles on the tooth surface that prevents

dental decay. Human ex vivo clinical trials suggested that regular tea drinking

may decrease the incidence and severity of caries (Hamilton-Miller,

2001).This extends to antiviral activities, where many pronounced activities

were reported for enveloped viruses (Song & Seong, 2007).

Anti-diabetic

Anti-diabetic is the beneficial effect of green tea. Green tea has been used to

control blood sugar levels or regulate glucose level in the body. An animal

studies was conducted by Sarangi (2009), revealed that green tea may have

properties to prevent development of Type 1 diabetes and slow the

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progression once it has developed. The type 1 diabetes also called as juvenile

diabetes is a chronic disease which the pancreas fail to produce insulin either

or produces a little. Insulin is an essential hormone produce by our body to

convert glucose (sugar), starches and other foods into energy. Tea

polyphenols lower the serum glucose by inhibiting the activity of the starch

digesting enzyme, amylase. Tea inhibits both salivary and intestinal amylase.

As a result, the starch is broken down more slowly and the sudden rise in

serum glucose is minimized (Sarangi, 2009).

Type 2 diabetes mellitus is a common disease that interferes with the body’s

ability to store energy from food (Sarangi, 2009).Severe complication may

occur for those suffering this type of diabetes. Painful diabetic peripheral

neuropathy (PDPN) is among common complication of diabetes mellitus

(Cathelijne et al., 2015). Diabetic peripheral neuropathy is a nerve damage

caused by chronically highly intake of glucose in dietary. This diabetic

peripheral neuropathy may lead to numbness, pain and loss of sensation.

Daily consumption of green tea can reduce the risk of developing diabetes. Iso

and his co-worker (2006), opined from a study that people who were frequent

drinkers of green tea (>6 cups per day) were less likely to develop this

diabetes than those who drank less than one cup of these beverages per

week.

2.2 Islamic Perspectives of Green Tea Polyphenols

2.2.1 Al-Quran

Green Plant in Al-Quran

“And it is He who sends down rain from the sky, and We produce thereby the

growth of all things. We produce from it greenery from which We produce

grains arranged in layers. And from the palm trees - of its emerging fruit are

clusters hanging low. And [We produce] gardens of grapevines and olives and

pomegranates, similar yet varied. Look at [each of] its fruit when it yields and

[at] its ripening. Indeed in that are signs for a people who believe”.

(Al-Quran. Al-An’am 6:99)

The Origin of Variety Plant

“And within the land are neighboring plots and gardens of grapevines and

crops and palm trees, [growing] several from a root or otherwise, watered with

one water; but We make some of them exceed others in [quality of] fruit.

Indeed in that are signs for a people who reason”.

(Al-Quran. Ar-Ra’d 13:4)

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2.2.2 Hadith

Every Disease Has Its Cure

Narrated Abu Hurairah (radiAllahu anhu) that the Prophet (sallAllahu alaihi wa

sallam) said: “There is no disease that Allah has sent down except that He

also has sent down its treatment”.

(Hadith narrated by Abu Hurairah)1

Imam an-Nawawi in his commentary on Sahih Muslim said: Al-Khattabi in his

Sunan mentioned that the rhetorical device of speaking in general terms, yet

intending by it a specific thing, is being utilized here. There is not a single type

of plant, which contains the cure for a disease and a cure for another disease

which requires the opposite of that which is present in the same plant. Rather,

what he intended is that it’s a healing from every disease which occurs from

every cold, humidity and expectoration.2

From this hadith, we can see that every single things that Allah created in this

world are beneficial and useful for His servants. For instance, He had created

dates that contain high quantity of iron minerals which very good to treat

anemia and constipation. This is one of the reasons why the Muslim scholars

advanced so much in medicine because they have faith in Prophet

Muhammad’s words that for every disease have its cure and they were

motivated enough to perform the research on plants, fruits and other

resources to seek for the treatments of every diseases.

Treatment of Any Diseases Need Efforts to Recover

Usamah bin Sharik said, “Some Bedouins asked, ‘O Allah’s Messenger

(PBUH)! Shall we treat (our illness)?’ He said, ‘Yes, O worshippers of Allah!

Use remedies. For indeed Allah did not make a disease but made a cure for it,

except for one disease.’ They said, ‘O Allah’s Messenger (PBUH)! What is it?’

He said. “Old age”.

(Hadith narrated by Abu Dawud)3

Some people whom suffer from a disease leaves everything to Allah S.W.T.

without put in any efforts to recover. It cannot be denied that Allah have the

key to recover all of the diseases in this world but instead of that, we as His

servants are recommended to seek for remedy before leave the rest to Him.

1 Sahih al-Bukhari, vol. 7, book 71, no. 582 2 Adeel.Khan. 12 January 2014. Imam Nawawi commentary on Sahih Muslim. http://www.answering- christianity.com/blog/index.php?topic=1440.0. 3 Sunan Abu Dawud, Vol. 4, Chapters on Medicine, Jami’ At-Tirmidhi. No.2038; Sunan Abu Dawud, Vol.4, Book of Medicine. No.3855

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Furthermore, He had provided a lot of natural resources for instance green

plant, fruits and others creation in order to facilitate human in finding

remedies.

2.2.3 Islamic Philosophy

In the Thirteenth Century, Arabic doctors like al-Razi, Ibn Sina, and Ibn Rushd

had made many additions to the list of herbs, plants and drugs known to the

Greeks. The Arabic physicians whose dietary repertoire were introduced other

great aspects of therapy and dietetics which had been enriched by the variety

of dishes and vegetables to be found in the lands of the vast Islamic empire.

Ibn Sina in the third part of his book, al-Qanun had gave a full description of

the various of illness which one of them is about neurological illness. To treat

this illness, he was diverse and varied treatments and remedies were based

on simple components and on what he could prepare using green plants. Ibn

Sina also had preferred prevention to treatment and natural rather than

artificial means (Al-Hassan et al., 2001).

Many of the Muslims’ medical philosophers and physicians during the past

sixteenth century had been used natural green plants as an alternative of

remedies to treat their patients even though at that time the technologies was

not so advanced to do an experimentation on the green plants. However,

because of their belief on hadith of Prophet Muhammad had said which is

everything that Allah has create in this earth has benefits to human beings

and every diseases have remedies except death and this be a great

motivation for them to find the treatment.

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CHAPTER III

CONCLUSION

Based on this review, it is proved that green tea is one of the herbaceous

plant that possess lots of benefits for human health. From this study, we had

discover the effectiveness of green tea extract as a preservative. The main

point that make up the uniqueness of this plant is the powerful antioxidant

composed by the polyphenols which have the ability to treat cancer, obesity,

diabetes and also promote oral health. Most of these discovery had been

popularized by the western scholars but in fact the study of green tea had

been started hundred years ago by the Islamic philosophers reinforced by the

holy Al-Quran and other Islamic scriptures. In conclusion, it is proven that the

green tea provide numerous benefits which render it to become more

preferable preservative that is widely used in the health products and in the

cosmetic world nowadays.

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