(TANNINS)5 Plants containing the secondary

metabolite (Tannins). there medicinal

uses, traditional uses, there chemical

structures and qualitative tests for

this secondary metabolite.

BY

Anumah Abdulraheem okehi

COURSE: CH514 (Natural product chemistry)

COURSE LECTURER: Prof. H.M. Adamu

1

ContentsAbstract...........................................................4

Acknowledgement....................................................4Introduction.......................................................5

So what are tannins?.............................................6Classification of the tannins based on their structural properties. 8

Different polyol units of the tannins..............................9Different galloyl derivatives of gallotannins, ellagitannins, and complex tannins...................................................10Single tannin classes.............................................12

Gallotannins....................................................12Ellagitannins...................................................15

Complex tannins.................................................19Condensed tannins...............................................19

Plants containing Tannins.........................................221. Aloe Vera (Aloe barbadensis Miller}............................22

Medicinal Uses..................................................23Aloe Helps with Digestion.....................................23

1. Aloe Helps in Detoxification...............................232.  Aloe Alkalizes the Body...................................23

3. Cardiovascular Health.....................................234. Aloe Helps Boost the Immune System........................23

5. Aloe Vera is Great for the Skin...........................24Traditional uses................................................24

2. Tea Tree (Melaleuca alternifolia}..............................25Medicinal Uses..................................................26

Traditional uses................................................27

2

3. Lemon balm (Melissa Officinalis)...............................29Medicinal uses..................................................30

Traditional uses................................................324. Thyme (Thymus Vulgaris)........................................33

Tra ditional uses of thyme......................................34Medicinal uses..................................................35

5. Chamomile (Matricaria chamomilla L.)...........................38Traditional uses................................................40

Medicinal uses..................................................41Anti-inflammatory and antiphlogistic properties...............41

Anticancer activity...........................................41Common cold...................................................41

Cardiovascular conditions.....................................42Colic/Diarrhoea conditions....................................42

Qualitative Test for Tannins......................................43Goldbeater's skin test..........................................43

Ferric chloride (FeCl3) test....................................43Other methods...................................................43

Hide-powder method..............................................43Stiasny's method................................................43

References........................................................44

3

Abstract

Nature is a unique source of structures of high stereo

chemical diversity, many of them possessing interesting

biological activities and medicinal properties. In the context

of the worldwide spread of deadly conditions such as AIDS and

a variety of cancers, an intensive search for new lead

compounds for the development of novel pharmacological

therapeutics is extremely important. The fact that the

biological activity of tannin-containing plant extracts has

been known for ages has led, especially during the last two

decades, to the isolation and characterization of many

representatives of this class. The group of unambiguously

characterized tannins includes more than 1000 natural

products. In extensive biological tests many representatives

of the tannins exhibited antiviral and antibacterial

properties, but especially prominent was the antitumor

activity. Certain tannins, for example, are able to inhibit

HIV replication selectively.

This assignment is aimed at expanding the students chemical

knowledge on the need to actually cherish our natural

4

endowment especially plants and also to put into documentation

what tannin are actually.

Acknowledgement

We would like to gratefully and sincerely thank Professor

Adamu for his guidance, understanding, patience, friendship

and most importantly for giving us the opportunity to develop

ourselves as regards to this research work.

Sir, your mentorship was paramount in providing a well-rounded

experience consistent our long-term career goals.

With this, you have encouraged us to not only grow as an

experimentalist and a chemist but also as an instructor, an

independent thinker and a researcher. We are not sure many

graduate students are given the opportunity to develop their

own individuality and self-sufficiency by being allowed to

work with such independence. Thank you Prof.

Introduction

The name ‘tannin’ is derived from the French ‘tanin’ (tanning

substance) and is used for a range of natural polyphenols.

Since ancient times it is known that certain organic

substances have tanning properties and are able to tan animal5

skins to form leather. Prehistoric tribes already knew about

the tanning of protective animal hides with brain material and

the fat of the killed animals.2 However, precisely what

happens to the skin during the tanning process was only

elucidated during the twentieth century with the help of

modern analytical techniques. the Real tanning is understood

as the crosslinking of the skin’s collagen chains, while false

tanning entails filling

of hollow spaces between the skin’s collagen chains. The

traditional tanning of animal skins by means of plant tannins

has been replaced gradually by mineral tanning, as represented

by alum tanning (or glacé tanning, a variant of alum tanning)

and more recently, since the end of the nineteenth century, by

chromium tanning. In nature the tannins are found worldwide

in many different families of the higher plants such as in

chestnut and oak wood, Divi-Divi, Sumach, Myrobalaen, Trillo,

Valonea or plant galls; depending on their origin, their

chemistry varies widely, having a molar mass of up to 20000 D.

High tannin concentrations are found in nearly every part of

the plant, such as in the bark, wood, leaves, fruit, roots,

and seed. Frequently an increased tannin production can be

associated with some sickness of the plant. Therefore, it is

assumed that the biological role in the plant of many types of

tannin is related to protection against infection, insects, or

animal herbivory. The tannins appear as light yellow or white

amorphous powdnfers or shiny, nearly colourless, loose masses,

with a characteristic strange smell and astringent taste.

6

The tannins are applied widely, with uses ranging from tanning, known over

millennia (Mediterranean since ca. 1500 BC), through medicinal uses to uses in

the food industry. In medicine, especially in Asian (Japanese and Chinese)

natural healing, the tannin-containing plant extracts are used as astringents,

against diaurrhoea, as diuretics, against stomach and duodenal tumours, and

as anti-inflammatory, antiseptic, and haemostatic pharmaceuticals. As tannins

can precipitate heavy metals and alkaloids (except morphine), they can be

used in poisonings with these substances. It is also becoming clear that

tannins often are the active principles of plant-based medicines.

Tannins are used in the dyestuff industry as caustics for

cationic dyes (tannin dyes), and also in the production of

inks (iron gallate ink). In the food industry tannins are used

to clarify wine, beer, and fruit juices. Other industrial uses

of tannins include textile dyes, as antioxidants in the fruit

juice, beer, and wine industries, and as coagulants in rubber

production. Recently the tannins have attracted scientific

interest, especially due to the increased incidence of deadly

illnesses such as AIDS and various cancers. The search for new

lead compounds for the development of novel pharmaceuticals

has become increasingly important; especially as the

biological action of tannin containing plant extracts has been

well documented. During the last twenty years many

representatives of this class of compounds have been isolated

and characterized.

Currently known tannins with unambiguously determined

structures already number far more than 1000 natural products.

In extensive biological tests many representatives of this

class were found to have antiviral, antibacterial, and,

7

especially, antitumor activity. For example, certain tannins

can selectively inhibit HIV replication.

The nomenclature of the tannins is full of misunderstanding,

erroneous interpretations, and changes caused by advances in

this field. Not all tanning substances can be called tannins,

and on the other hand many types of tannin do not possess

tanning properties but are counted with the tannins because of

their structural characteristics.

So what are tannins?

Bate-Smith and Swain defined the plant tannins as water

soluble phenolic compounds with a molar mass between 300 and

3000, showing the usual phenol reactions (e.g. blue colour with

iron(iii) chloride), and precipitating alkaloids, gelatins and

other proteins. However, this definition does not include all

tannins, since, more recently, molecules with a molar mass of

up to 20000 D have been isolated that should also be

classified as tannins on the basis of their molecular

structures.

Griffith defined tannins as “macromolecular phenolic

substances” and divided them in two major groups, the

‘hydrolysable’ and ‘condensed’ tannins. This definition of the

tannins ignores the low molecular and monomeric tannins with a

molar mass below 1000 D.

Haslam classified the plant polyphenols into two broad

structural themes:

(i) Galloyl and hexahydroxydiphenoyl esters and their

derivatives.

(ii) (ii) Condensed proanthocyanidins.

8

Galloyl and hexahydroxydiphenoyl esters and their derivatives

have been further classified into several broad categories:

(1) Simple esters. (2) Depside metabolites (syn-gallotannins).

(3) Hexahydroxydiphenoyl and dehydrohexahydroxydiphenoyl

esters (syn-ellagitannins) based upon: (a) 4C1 conformation of

D-glucose; (b) 1C4 conformation of D-glucose; (c) ‘open-chain’

derivatives of D-glucose. (4) ‘Dimers’ and ‘higher oligomers’

formed by oxidative coupling of ‘monomers principally those of

class (3) above. While in Haslam’s article, complex tannins

have not been mentioned, in the newly published review by

Ferreira et al. only two classes of tannins, namely: (i)

condensed tannins and (ii) complex tannins are treated

exhaustively.

Gross adopted the classical definition of tannins that was

formulated by Freudenberg in 1920 cited therein.

According to Freudenberg and Gross tannins are usually divided

into the flavonoid derived condensed tannins, and into

hydrolysable tannins. The former are divided into two groups,

namely: (i) gallotannins, which include also meta-depsids, and

(ii) ellagitannins. Also, the definition of tannins as a

mixture of ‘flavolanes of varying structure’ at best only

covers some tannins and does not include the hydrolysable

tannins which form a considerable portion of the tannins. An

organic chemistry textbook87 defines tannins as: “C- and O-

glycosidic derivatives of gallic acid (3,4,5-trihydroxybenzoic

acid)”. This definition also describes only some of the

tannins and does not include the condensed tannins based on

flavan-3-ol (catechin) units. It is therefore necessary, as a

9

result of the recently greatly expanded structural range of

the tannins, to formulate a definition that includes all

tannins.

Tannins are polyphenolic secondary metabolites of higher

plants. Corresponding polyphenolic natural products have not

yet been isolated from lower plants such as algae, or from the

animal kingdom. The polyphenolic structure of the secondary

metabolites from higher plants is a necessary but not

sufficient requirement for membership of the tannin class.

When the structural characteristics of the currently known

tannins are analysed, the relatively low occurrence of C-

and/or O glycosidic derivatives of gallic acid is noteworthy.

However,

the characterized tannin structures show that, apart from the

galloyl glycosides, the galloyl residues can be linked to each

other or to other residues through their aromatic carbon

and/or phenolic oxygen atoms. By these and similar couplings

of two or more natural products to each other, nature provides

a nearly inexhaustible store of highly diverse structures. It

should be mentioned, however, that not all tannins must

necessarily contain a galloyl unit or derivative. Examples of

this type are found in the so-called condensed tannins that

are built up from flavanoid precursors. The condensed tannins,

constructed from at least two linked catechin units (C-4 with

C-8 or with C-6, see Fig. 1 below, compound 4), can

alternatively be linked through the hydroxy group of C-3 of

each catechin unit to a galloyl unit.

10

Classification of the tannins based on their structural

properties

Due to the enormous structural diversity of the tannins a

systematic classification system based on specific structural

characteristics and chemical properties would provide a

convenient framework for further study. The observation that

many tannins can be fractionated hydrolytically into their

components, for example by treatment with hot water or with

tannases, led to the classification of such tannins as

‘hydrolysable tannins’. Non hydrolysable oligomeric and

polymeric proanthocyanidins were classified as condensed

tannins. Therefore, the term ‘hydrolysable tannins’ includes

both the gallotannins and the ellagitannins. It should also be

mentioned here that there are ellagitannins that are not

hydrolysable, because of a further C–C coupling of their

polyphenollic residue with the polyol unit, but are

nevertheless for historical reasons classified as hydrolysable

tannins [see Fig. 6, vescalagin].

In 1985 the first tannins were described that contained, in

addition to the hexahydroxydiphenoyl (HHDP) units (the

characteristic structural element of the monomeric

ellagitannins), also C-glycosidic catechin units [see Fig. 9,

acutissimin A (76).These tannins were originally classified as

‘non-classified tannins’, because they are only partially

hydrolysable due to the C–C coupling of their catechin unit

with the glycosidic part. To properly place these ‘non-

classified tannins’ in some scheme, the terms ‘complex

11

tannins’ and flavanoellagitannins were established over the

following years. These examples clearly show that the division

of the tannins into two groups, viz. hydrolysable and non-

hydrolysable or condensed tannins cannot do justice to the

structural diversity of the tannins. The terms

‘flavanotannins’ or ‘condensed flavonoid tanning substances’

that are occasionally found in the literature denote tannins

consisting of catechin units. The polymeric flavanotannins,

constructed from coupled flavan-3-ol (catechin) units, belong

to the condensed tannins (oligomeric and polymeric

proanthocyanidins).

Fig.1

Classification of Tannins

12

On the basis of their structural characteristics it is

therefore possible to divide the tannins into four major

groups: Gallotannins, ellagitannins, complex tannins, and condensed tannins

(Fig. 1).

I. Gallotannins are all those tannins, in which galloyl

units or their meta-depsidic derivatives are bound to

diverse polyol-, catechin-, or triterpenoid units.

II. Ellagitannins are those tannins in which at least

two galloyl units are C–C coupled to each other, and do

not contain a glycosidically linked catechin unit.

III. Complex tannins are tannins in which a catechin unit

is bound glycosidically to a gallotannin or an

ellagitannin unit.

IV. Condensed tannins are all oligomeric and polymeric

proanthocyanidins formed by linkage of C-4 of one

catechin with C-8 or C-6 of the next monomeric catechin.

Different polyol units of the tannins

The standard metabolism for the biosynthesis of tannins in

higher plants uses various building blocks that are coupled to

each other. For example, the gallotannins are biosynthesized

by the different coupling possibilities of a polyphenolic

building block such as gallic acid with diverse polyols such

as D-glucopyranose. A complete listing of the structures of

all known tannins falls outside the scope of this article;

however, the structures of the currently known tannins are

summarized by way of a fractionation of their components. The

following are some of the polyalcoholic components of the

13

tannins: D- Glucopyranose (5), D-hamamelose (6), sucrose

(7),92 shikimic acid (8), quinic acid (9), scyllo-quercitol (10)

93 and protoquercitol (11),94 salicin or 2-hydroxymethylphenyl

β-D- glucopyranoside (12),95 D fructopyranose (13), 6-

cinnamoyl-D- glucopyranose (14), 1,5-anhydro-D-glucitol,96

3,5-dihydroxyphenyl β-D-glucopyranoside (15),97 2-coumaroyl-D-

glucopyranose (16), 4-hydroxy-2-methoxyphenyl β-D-

glucopyranoside (19),98 4-hydroxy-3-methoxyphenyl β-D-

glucopyranoside (20),98 3,4,5-trimethoxyphenyl β-D-

glucopyranoside (21),98 2,6 dimethoxy-4-hydroxyphenyl β-D-

glucopyranoside (22),98 4-carboxy-2,6-dihydroxyphenyl β-D-

glucopyranoside (23),99 3-carboxy-5,6-dihydroxyphenyl β-D-

glucopyranoside (24),99

4-(3-oxobutyl)phenyl β-D-glucopyranoside (25),99 triterpenoid

26,77,78 salidroside (27),89,92,100 methyl β-D-glucopyranoside

(28),92 maclurin C-β-D-glucopyranoside (29),92 maclurin 2_-O-

( p-hydroxybenzoyl)-C-β-D-glucopyranoside (30),92 mangiferin

C-β-D-glucopyranoside (31),92 iriflophenone C-β-D-

glucopyranoside (32),101 isomangiferin C-β-D-glucopyranoside

(33),92 D-gluconic acid (34),15 D-glucitol (35),89 glycerol

(36), glycosidically bound Catechins 37, Catechins,

epicatechins, gallocatechins, and epigallocatechins 3880,88 etc.

(Fig. 2). The hydroxy functions of the tannin polyol residues

may be linked fully or only partly with galloyl units or their

derivatives, in which case they may be linked to several other

residues.3, 4, 77, 78. the diversity of tannin structures is

further enriched by the capability of the anomeric centre of

the glycosidic components

14

to form C- and/or O-glycosidic, ester or acetal bonds, in the

β or α form with a great variety of building blocks.

Different galloyl derivatives of gallotannins, ellagitannins,

and complex tannins

In many tannins two galloyl units are linked to each other

through their aromatic carbon atoms to form an axially chiral

hexahydroxydiphenoyl (HHDP) unit (39, 40), which is the

characteristic structural element of the monomeric

ellagitannins. Linking the galloyl unit of the tannins, for

instance via the phenolic oxygen atom, to a further galloyl

unit leads to formation of a meta-digalloyl unit (50), the

characteristic structural element of the meta-depsides which

are also reckoned with the gallotannins.

Other important galloyl derivatives found in many types of

tannin are: HHDP (39, 40), flavogallonyl (41), valoneoyl (Val)

(42), sanguisorboyl (San) (43), Dehydrohexahydroxydiphenoyl

(DHHDP) (44, 45 and 46), and gallagyl (Gal) (47),

elaeocarpusoyl (Ela) (48), dehydrodigalloyl (49), meta-

digalloyl (50), chebuloyl.

15

Fig. 2 Polyol residues of Tannin

16

Different Galloyl units of Tannins

(Che) (51), trilloyl (52), dehydrochebuloyl (DHChe) (53),

brevifolyl (54) etc. (Fig. 3).3,4,77,78,104–106

Single tannin classes

For clarity the four major groups of the tannins are briefly

discussed by way of some selected examples.

17

Gallotannins

Gallotannins are the simplest hydrolysable tannins, containing

a polyphenolic and a polyol residue. Although a great variety

of polyol residues are possible, most of the gallotannins

isolated from plants contain a polyol residue derived from D-

glucose. The hydroxy functions of the polyol residues may be

partly or fully substituted with galloyl units. In the case of

partial substitution with galloyl residues the remaining

hydroxy groups may be either unsubstituted or substituted with

various other residues. For example, the anomeric centre of

the glycosidic residues of the gallotannins may be

unsubstituted (α,β mixture) or substituted, in α or β form, as

ester or acetal. The metadepsides (or ‘syn-gallotannins’) 10

also belong to the gallotannin group. Their galloyl residues

are esterified with the polyol residue and also with one or

more linked galloyl units in the meta position relative to the

galloyl units’ carboxyl groups. The gallotannins 2,3,4,6-tetra-

O-galloyl-D-glucopyranose (TGG) (55) and 1,2,3,4,6-penta-O-

galloyl-β--glucopyranose (β-PGG) (56), found in many plant

families, are key intermediates in the biosynthesis of nearly

all hydrolysable plant polyphenols.107–110 Gallotannins in

which the polyol residues are coupled to cinnamoyl (17) or

coumaroyl (18) groups (e.g. 57 and 58) are relatively

scarce.97,102,103 Most of the gallotannins substituted with a

galloyl unit at the anomeric centre of their D-glucosyl unit

have the β configuration at the anomeric centre. There are,

however, also some natural products such as 1,4-di-O-galloyl-

α-D-glucopyranose (59),17 where the anomeric centre of the D

18

glucopyranose has the α configuration.111–113 The structural

diversity of the gallotannins is demonstrated by some selected

examples (Fig. 4).

Fig 4

Structure of some of the gallotannins

19

Fig. 5 Some of the coupling possibilities of D-

glucopyranose in the 1C4 or 4C1 conformation with (R)- or (S)-

configured HHDP units.

Ellagitannins

With more than 500 natural products characterized so far, the

ellagitannins form by far the largest group of known

tannins.114 Ellagitannins are formed from the gallotannins by

the oxidative coupling of at least two galloyl units (62)

(Figs. 4 and 5), yielding an axially chiral HHDP unit (39 or

40). The chirality is caused on the one hand by the bulky ortho

20

substituents to the biaryl axis, and on the other hand by the

atropisomerism caused by the inhibition of free rotation

around the axis. This is caused by the esterification of both

ortho carboxy groups

with the polyol (usually D-glucopyranose, Fig.

3).3,4,77,78,104–106 Remarkably, all ellagitannins with HHDP

units linked via the 4,6 or the 2,3-positions of their -

glucosyl unit have an (S)- configured HHDP unit, while linkage

via the 3,6-positions seems to lead only to an (R)-configured

HHDP unit.77,78,115.

Esterification to other positions of the sugar molecule, for

example a 1,6-coupling 20,74 is rarely found in nature. In the

majority of ellagitannins with an axially chiral glucose-bound

HHDP unit, both the configuration of the biaryl unit and the

conformation of the D-glucosyl unit are determined by their

linkage positions. An HHDP unit bound to the 2,3- or 4,6- or

1,6-positions of D-glucopyranose in the natural products

always has the (S)-configuration, while most 2,4- or 3,6-

coupled HHDP units favour the (R)-configuration.

Thermodynamics govern the resulting D-glucose conformation,

which again is determined by the coupling positions of the

HHDP unit to the glucopyranose ring. While the glucopyranosyl

21

Fig. 6 Typical ellagitannins with a

C-glycosidic bond 77,78 and with a D-gluconic acid unit.

22

Fig. 7 The structure of a rare ellagitannin with a

triterpenoid structural unit, and of a rare α-configured

ellagitannin.

assumes a 4C1 conformation in the case of 2,3- or 4,6-HHDP

coupling, a 1,6- or 3,6- or 2,4-HHDP coupling always favours

the thermodynamically less stable 1C4 conformation (Fig. 5).

For both the C-glycosidic ellagitannins and the ellagitannins

with a D-gluconic acid unit the coupling of the HHDP unit via

the 2,3- and 4,6-positions of the D-glucosyl is highly

characteristic. The C-glycosidic bond between the open-chain

sugar and the bidentate substituent is always formed at C-1 of

23

the sugar. Typical examples of these groups of substances are

vescalagin (70) 77,78 with a C-glycosidic bond, and

lagerstannin C (71) 15 with a D-gluconic acid unit (Fig. 6).

Seemingly, for the routine biosynthesis of the tannins, nature

does not use only D-glucopyranose for the esterification with

gallic acid. For example, D-hamamelose (6) and complex

triterpenoids such as 26 are also used in tannin biosynthesis.

As example of an ellagitannin with a triterpenoid structural

unit, which could be isolated only seldomly from natural

sources, the natural product castanopsiniin A (72) 77,78 can

be mentioned. Also, the ellagitannin group contains few

examples where the anomeric centre of D-glucopyranose has the

α-configuration. Heterophylliin A (73) 36 is one of the rare

examples of this type

(Fig. 7).

24

Fig 8 the structures of punicalin (74) and

terflavin B (75).

As early as 1977 Mayer et al. published the isolation of the

ellagitannin punicalin (74) from the fruit husks of Punica

granatum L.116 However, the correct structure was published

25

only in 1986 by Nishioka et al.24 Punicalin [4,6-(S,S)-gallagyl-

D-glucopyranose] (74) contains the so-called gallagyl unit as

characteristic structural element. The gallagyl unit itself

is constructed from a lactonized HHDP nucleus which is C–C

coupled with two galloyl (3,4,5-trihydroxybenzoyl) residues.21

The punicalin structure is completed with a D-

Glucosyl unit which is linked via two hydrolytically cleavable

ester bridges to the gallagyl building block. Little is known

about the biosynthesis of punicalin (74). It is known,

however, that terflavin B (75), also isolated from Punica

granatum L., is a key intermediate in the biosynthesis.

Terflavin B can be transformed directly into punicalin (74) by

oxidative coupling (Fig. 8).21,117

Complex tannins

The structures of the complex tannins are built up from a

gallotannin 43 unit or an ellagitannin 91 unit, and a catechin

unit.4,77,78,91 One example from this substance class is

acutissimin A (76), having a flavogallonyl unit

(nonahydroxytriphenoyl unit) bound glucosidically to C-1, and

linked via three further hydrolysable ester bridges to the D-

glucose derived polyol (Fig. 9).77,78

Condensed tannins

One of the striking properties of the monomeric catechins and

leukoanthocyanidins, that have no tanning properties, is their

ability to be converted into oligomers and polymers that do

have tanning properties, by the action of acids or

enzymes.3,4,77,78,88,91,118 Condensed tannins are oligomeric

26

and polymeric proanthocyanidins consisting of coupled flavan-

3-ol

(catechin) units (oligomeric or polymeric proanthocyanidins =

condensed proanthocyanidins = condensed tannins).

Biosynthetically the condensed tannins are formed by the

successive condensation of the single building blocks, with a

degree of polymerization between two and greater than fifty

blocks being reached. The coupling pattern of the catechin

units in condensed tannins can vary considerably. For example,

many con densed tannins are known where the coupling of the

single units is by way of position C-4 of the first unit

linked with C-8 (or C-6) 4,119 of the second unit, which may

have a different substitution pattern.4,120 The tannins found

in red wine (and to a lesser extent in white wine) are this

type of condensed tannins.

The properties of these tannins, and especially their

importance to winemaking, depend on their specific reaction

with proteins, which in turn is directly related to their

degree of polymerization. Oligomers and polymers consisting of

two to ten catechin units are also known as flavolans.11 Some

typical condensed tannins with unsubstituted catechin units

are procyanidin B2 [epicatechin-(4β 8)-epicatechin (77)],

proanthocyanidin A1 [epicatechin- (4β 8,2β O 7)-catechin

(78)], proanthocyanidins A2 [epicatechin-(4β 8,2β O 7)-

epicatechin (79)],

and proanthocyanidin C1 [epicatechin-(4β 8)-epicatechin- (4β

8)-epicatechin (80)] (Fig. 10).

27

Fig. 9 Acutissimin A, the usual

representative of the complex tannins.77,78

28

Fig. 10 Different linkage patterns of condensed tannins, for

example procyanidin B2 (77), proanthocyanidin A1 (78),

proanthocyanidin A2 (79) (79) and proanthocyanidin C1 (80).

29

Plants containing Tannins

From literature, I can gallantly conclude that all plants

contains tannin but the only different lies in the percentage

yield from any plants.

1. Aloe Vera (Aloe barbadensis Miller}

Structures of some of the active compounds in the plant

30

The aloe vera plant is often found near water in sand or

rocks. It has thick stiff leaves and slender, orange-colored

flower spikes. The gel found in the leaves is commonly used to

speed the healing of skin conditions, including burns and

wounds. The sap found in the base of the leaf is used as a

digestive stimulant and a strong laxative.

Medicinal Uses

Aloe Helps with Digestion

Poor digestion is related to many diseases. A properly functioning digestive tract is one of the keys and foundationsof health. Aloe is known to soothe and cleanse the digestive tract and help improve digestion. The interesting thing about taking aloe internally is that, because it is an adaptogen, ithelps with either constipation or diarrhea, helping to regulate your elimination cycles in whatever way you need.It’s been a great remedy for people with problems such as irritable bowel syndrome as well as acid reflux. Aloe also helps to decrease the amount of unfriendly bacteria and in ourgut keeping your healthy intestinal flora in balance. Aloe is also a vermifuge, which means it helps to rid the body of intestinal worms.

1. Aloe Helps in Detoxification

Aloe Vera is a gelatinous plant food, just like seaweeds and chia seeds. The main benefit to consuming gelatinous plant foods in your diet is that these gels move through the intestinal tract absorbing toxins along the way and get eliminated through the colon. This will help the proper elimination of waste from your body and help the detoxification of your body.

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2.  Aloe Alkalizes the Body

Disease cannot manifest in an alkaline environment. Most people are living and subsisting on mostly acidic foods. For great health, remember the 80/20 rule – 80% alkaline forming foods and 20% acidic. Aloe vera is an alkaline forming food. It alkalizes the body, helping to balance overly acidic dietary habits.

3. Cardiovascular Health

There hasn’t been a lot of studies conducted on aloe’s effect on cardiovascular health, but there has been some research to show that aloe vera extract injected into the blood, greatly multiplies the oxygen transportation and diffusion capabilities of the red blood cells. According to a study published in the 2000 issue of the British Medical Journal, beta sitosterol helps to lower cholesterol. By regulating blood pressure, improving circulation and oxidation of the blood, lowering cholesterol, and making blood less sticky, aloe vera juice may be able to help lower the risk of heart disease.

4. Aloe Helps Boost the Immune System

I think given the stresses of our daily lives, every one can use a boost to their immune systems. The polysaccharides in aloe vera juice stimulate macrophages, which are the white blood cells of your immune system that fight against viruses. Aloe is also an immune enhancer because of its high level of anti-oxidants, which help combat the unstable compounds known as free-radicals, contributing to the aging process. (Free radicals are a bi-product of life itself, it is a naturally occurring process but we can overload ourselves with unnecessary free-radicals by living an unhealthy lifestyle). Aloe is also an antipyretic which means it used to reduce or prevent fever.

5. Aloe Vera is Great for the Skin

Because of aloe’s well-known healing properties for the skin, aloe is one of the primary compounds used in the cosmetic industry. It is a known vulnerary, (meaning it helps heal

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wounds) and is great for applying topically to burns, abrasions, psoriasis and even to bug bites. Aloe acts as an analgesic, acting to help relieve pain of wounds. It’s feels especially good to cut a stem of aloe, place it in the fridge and rub it on sun burnt skin – the immediate soothing effect feels like an absolute lifesaver. Aloe is also an antipruritic: A substance that relieves or prevents itching. Aloe vera is an astringent: which causes the contraction of body tissues, typically used to reduce bleeding from minor abrasions. Due to aloe’s high water content (over 99% water) it is a great way to hydrate, moisturize and rejuvenate the skin and fits within my general guideline: “Don’t put anything on your skin that you wouldn’t eat!” Aloe increases the elasticity of the skin making it more flexible through collagen and elastin repair. Aloe is an emollient, helping to soften and soothe theskin. It helps supply oxygen to the skin cells, increasing thestrength and synthesis of skin tissue and induces improved blood flow to the skin through capillary dilation.

Traditional uses 1. Aloe vera gel is used as an ingredient in commercially

available lotion, yogurt, beverages and some desserts. 2. Aloe vera gel is used for consumption and relief of

digestive issues such as heart burn and irritable bowel syndrome.

3. It is common practice for cosmetic companies to add sap or other derivatives from Aloe vera to products such as make up, tissues, moisturizers, soaps, sunscreens, incense, razors and shampoos.

4. Other uses for extracts of Aloe vera include the dilution of semen for the artificial fertilization of sheep, use as fresh food preservative, and use in water conservation in small farms.

5. Aloe vera has a long association with herbal medicine, although it is not known when its medical applications were first discovered. Aloe vera is non-toxic, with no known side effects, provided the aloin has been removed by processing. Taking Aloe vera that contains aloin in excess amounts has been associated with various side effects. However, the species is used widely in the traditional herbal medicine of China, Japan, Russia, South Africa, The United States, Jamaica and India.

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Aloe vera is alleged to be effective in treatment of wounds.

The big leaves contain sap, which works amazingly against:

Burns

Wounds and cuts

Eczema

Skin allergies

The intake of aloe vera juice can heal:

 digestive problems and appetite

Chronic constipation

ulcerative colitis

2. Tea Tree (Melaleuca alternifolia}

Structures of some of the active compound in the plant

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This shrub is generally found in swamps and contains tiny

green leaves and wispy white flowers. The essential oils taken

from this plant are a popular antiseptic used for stings,

burns, wounds and many other skin conditions. Tea trees are

also utilized for stimulating the immune system and for

helping to treat chronic fatigue syndrome.

Medicinal Uses1. Bad breath. Early research shows that adding tea

tree oil to an essential oil mixture containing peppermint and lemon oils can reduce bad breath.

2. Cold sores (Herpes labialis). Research so far suggests that applying 6% tea tree oil gel 5 times daily does not significantly improve cold sores.

3. Eyelid infection (blepharitis). Early research shows that tea tree might cure common eyelid infections and reduce the associated symptoms, including eye inflammation and vision loss.

4. Dandruff. Early research suggests that applying a 5%teat tree oil shampoo three minutes daily for four weeks reduces scalp lesions, scalp itchiness, and greasiness in patients with dandruff.

5. Dental plaque. Results from research examining the effects of tea tree oil on dental plaque are inconsistent. Some early research shows that brushing the teeth with a 2.5% tea tree oil gel twice daily for eight weeks reduces gum bleeding butnot plaque in people who have gingivitis caused by plaque. Also, using a mouthwash containing tea tree oil after a professional teeth cleaning does not seem to reduce plaque formation. However, rinsing with a specific product (Tebodont) containing tea tree oil and a chemical called xylitol does seem to reduce plaque.

6. Gingivitis. Results from research examining the effects of tea tree oil on gingivitis are inconsistent. Some early research shows that brushing the teeth with a 2.5% tea tree oil gel twice daily for eight weeks reduces gum bleeding but

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does not improve overall gum health in people who have gingivitis caused by plaque. However, rinsing with a specific product (Tebodont) containing tea tree oil and a chemical called xylitol seems to reduce gum inflammation.

Traditional uses

1. Tea Tree Oil for Acne

One of the most common uses for tea tree oil today is in skin care products, and it’s considered one of the home remedies for acne. One study found tea tree oil to be just as effectiveas benzoyl peroxide, but without the negative side effects of red and peeling skin.

You can make a tea tree oil acne face wash by mixing five drops of tea tree essential oil with two teaspoons of raw honey. Simply rub on your face, leave on for one minute, then rinse off.

2. Tea Tree Oil for Hair

Tea tree oil has proven very beneficial for the health of yourhair and scalp. Like coconut oil for hair, tea tree oil has the ability to soothe dry flaking skin, dandruff and even can be used for the treatment of lice. To make homemade tea tree oil shampoo, mix it in with aloe vera gel, coconut milk nutrition and other essential oils like lavender oil.

3. Tea Tree Oil for Cleaning

Another fantastic way to use tea tree oil is as a household cleaner. Tea tree oil have powerful antimicrobial properties and can kill off bad bacteria in your home. To make homemade tea tree oil cleaner, mix with water, vinegar and lemon essential oil.

4. Tea Tree Oil for Psoriasis and Eczema

Tea tree oil can help relieve any type of skin inflammation, including being used as a natural eczema treatment and for psoriasis. Simply mix one teaspoon coconut oil, five drops of

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tea tree oil and five drops of lavender oil to make homemade tea tree oil eczema lotion or body soap. In addition, if you have eczema or psoriasis, you should consider going on the GAPS diet and supplementing with vitamin D3.

5. Tea Tree Oil for Toenail Fungus and Ringworm

Because of its ability to kill parasites and fungal infections, tea tree oil is a great choice to use on toenail fungus, athlete’s foot and ringworm. Put tea tree oil undiluted on the area and, for stubborn fungi, it can also be mixed with oil of oregano. Tea tree oil has also been proven beneficial for treating and removing warts, so simply put tea tree oil directly on the area for 30 days.

You must have heard about tea green a lot, especially for

treatment against loss of hair and headaches. It contains

amazing benefits like antibacterial, anti-fungal and works

best as antiseptic. In addition, it treats:

Burns

Fever

Athlete foot

fatigue syndrome

Vaginal infections

Acne and warts

Insect bites

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3. Lemon balm (Melissa Officinalis)

Structures of some of the active compounds in the plants

39

i

Medicinal uses

1. Sleep

In a 15 day open-label study in persons with mild to moderate stress and anxiety coupled with sleep disturbances, supplementation of Melissa officinalis (7% Rosmarinic acid and 15%

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total hydrocinnamic acids) taking 300mg at breakfast and againbefore sleep (600mg total) noted reductions in anxiety-relatedinsomnia by 42% (Overall).[25]

Melissa officinalis is commonly consumed alongside Valeriana officinalis for the purpose of sedation, and at least one multicenter study using both in a combination noted that the supplement group (120mg Valerian (4.5:1 concentration) and Lemon Balm at 80mg (5:1 concentration) taken thrice before bed) after 30 days reported enhanced sleep quality (33% of respondents reported better sleep) which was greater than placebo (9% of the placebo group reported better sleep); treatment was very well tolerated with no significant side effects.[1] One other trial has noted that this combination waseffective in reducing restlessness and dyssomnia in children.[2]

Appears to have sedative properties and promote sleep quality,but there is relatively little evidence to support it as two well controlled studies are confounded with the inclusion of Valerian

2. Anxiety and Stress

In rats given Melissa officinalis extract (9.32% Rosmarinic Acid) at120-360mg/kg bodyweight for 15 days appeared to have anxiolytic effects in an open field test as well as an elevated maze test but not in a four-hole board test at the higher two doses (240mg/kg and 360mg/kg).[26] The anxiolyic effects (30-300mg/kg ethanolic extract) have in one study beencomparable to 1mg/kg Diazepam when dosed over 10 days, and appeared to be more effective in females (with only 300mg/kg being statistically significant in males, but all doses being effective in female rats).[27]

One study has noted that inhalation of lemon oil vapor has exerted anti-stress responses, and that these effects were related to serotonergic signalling (particularly the receptor 5-HT1A).[28]

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Two animal studies suggest anxiety reducing effects of oral Lemon Balm, with one noting that lemon vapor was also effective

In a clinical setting, an acute dose of 300 or 600mg Melissa officinalis prior to an acute stress test (DISS battery of tests[29]

followed with Mood assessment via Bond and Lader VAS mood scales[30]) noted that the higher dose was associated with improved self-reported calmness, reduced alertness (increased after test) following the test while the 300mg dose failed to significantly modulate mood.[31] Another acute study noted that a Lozenge containing Melissa officinalis was able to induce brain wave alterations similar to that of standard anxiolytics.[32]

Can reduce anxiety when dosed acutely (single dose taken before stressor)

In humans consuming 300mg Melissa officinalis (7% Rosmarinic acid and 15% total hydrocinnamic acids) at breakfast and again before sleep for 15 days in an open-label trial, there appearsto be general anxiolytic propeties in regards to anxiety-related eating problems (33% lower than baseline), emotional instability (7%), fatigue (18%), feelings of guilt (15%) or inferiority (18%), psychosomatic symptoms (33%) and intellectual disturbance (28%).[25]

Appears to reduce anxiety when taken over a period of time in humans (morning and nightly doses)

3. Memory and Learning

One study has noted that Melissa officinalis have nicotinic receptorbinding properties[33] as well as muscarinic.[34] One study has noted weak acetylcholinesterase inhibiting property with fresh, but not dried, leaves of Lemon Balm;[33] a subsequent study failed to replicated acetylcholinesterase inhibiting properties up to 0.25mg/mL.[6]

Subsequently, a study conducted noting incubation with Melissa officinalis noted that the extract had little ability to displace either Nicotine or scopolamine from the receptor.[35] This was followed up on in post-mortem human neural tissue where

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nicotine was displaced at moderate concentrations of 180-3120µg/mL and scopolamine at 2.69-4.31mg/mL (ethanolic herb extract) although it could be extracted into more effective fractions (the most potent noted fractions being 4.2µg/mL nicotine displacement and 102.6µg/mL for scopolamine) althoughthere still appears to be a large degree of variability.[6]

Appears to interact with acetylcholine receptors, there appears to be some agonistic (activating) properties that are very volatile (not reliable); if looking at solely the most effective fragments, the affinity at least appears respectable

In the hippocampal dentate gyrus of aged rats, Melissa officinalis at 50-200mg/kg daily was able to enhance neurogenesis (244.1-763.9% of control group, respectively) which was associated with reduced corticosterone concentrations.[24]

Has been noted to enhance neurogenesis in at least one rat study giving oral administration

300mg Melissa officinalis given prior to an acute stress test was noted to be (nonsignificantly) associated with improved answering on mathematical questions; increasing the dose to 600mg did not help in reaching statistical significance.[31]

Following ingestion of 600mg or 1600mg Melissa officinalis acutely, improvements relative to placebo are noted in quality of memory (percentage of answers or recollections that are correct) only with trends for improvement (not significant) were noted in picture-recall, delayed word recall, spatial memory and no influence was noted on working memory nor attention in this study, and self-reported attention was similar.[6] Sporadic improvements in memory quality (digital vigilance accuracy and choice reaction time accuracy) have been noted elsewhere.[35]

There appears to be comparatively weak cognitive enhancing properties assocaited with oral Melissa officinalis supplementation at higher doses (600-1600mg)

For cognitive parameters sometimes seen as adverse, 600-1600mgMelissa officinalis has been noted to reduce the speed of memory

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without influencing memory formation per se.[6] A reduction in rapid visual information processing has also been noted, with sporadic influences on false-positive processing (neither 600 nor 1600mg, but 1000mg, being associated with increased false-positives).[6] Another study to record spatial memory found a statistically significant reduction thereof following 300-900mg acute ingestion, this reduction was also noted for word recollection.[35]

The calming effects of Melissa officinalis may also reduce the speedof learning, possibly secondary to being slightly sedative or too 'calming'

4. Neuroprotection

In hippocampal corticol neurons deprived of oxygen, 10μg/mL Lemon Balm was associated with preserving roughly half of corticol neurons that would have been lost to hypoxia and alsoreduced concentrations of caspase-3 and DNA fragmentation (both indicative of apoptosis); concentrations of 200-500μg/mLshowed inherent cytotoxicity to neurons.[4] Neuroprotection hasalso been noted in hippocampal cells exposed to ecstasy.[36]

Appears to have neuroprotective effects in vitro in pro-oxidativetoxicity

In a model of hippocampal occlusion (mice) given 100mg/kg Lemon Balm for 2 weeks prior to occlusion treatment and continued thereafter noted reduced lipid peroxidation (MDA andTEAC) and the concentrations of HIF-1α, TNF-α and IL1-β (all induced during hypoxia) were effectively suppressed by Melissa officinalis.[4]

This may extend to living models undergoing hypoxia (lack of oxygen) in neural tissue

5. Pain

One study has note dose-dependent pain-reducing effects of oral ingestion of Melissa officinalis (ID50 of 241.9mg/kg) in mice subject to a battery of tests (acetic acid writhing,

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glutamate, and formalin) which seems to be related to the Rosmarinic Acid content.[37]

May have pain relieving properties, requires more researches.

Traditional usesLemon balm is a perennial herb from the mint family. The leaves, which have a mild lemon aroma, are used to make medicine. Lemon balm is used alone or as part of various multi-herb combination products.

Lemon balm is used for digestive problems, including upset stomach, bloating, intestinal gas (flatulence), vomiting, and colic; for pain, including menstrual cramps, headache and toothache; and for mental disorders, including hysteria and melancholia.

Many people believe lemon balm has calming effects so they take it for anxiety, sleep problems, and restlessness. Lemon balm is also used for Alzheimer's disease, attention deficit-hyperactivity disorder (ADHD), an autoimmune disease involvingthe thyroid (Graves' disease), swollen airways, rapid heartbeat due to nervousness, high blood pressure, sores, tumors, and insect bites.

Lemon balm is inhaled as aromatherapy for Alzheimer's disease.

Some people apply lemon balm to their skin to treat cold sores(herpes labialis).

In foods and beverages, the extract and oil of lemon balm are used for flavoring.

The leaves of this plant have mint like smell and provides

nourishing image. It has big summer flowers, which can be

rubbed against the skin for:

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Animal bites

Mosquito bites

Sores

Herpes

The nectar that is used with water in form of juice is

beneficial for:

Fevers

Colds and cough

Depression

Headaches

Upset stomach

Insomnia

4. Thyme (Thymus Vulgaris)

Some of the active compounds in the plant

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Some of the active compounds in

thymus vulgaris

Thyme is a fragrant herb that makes a wonderful addition to

your cooking, in part because it is rich in antioxidants.

Thyme contains health-boosting flavonoids including apigenin,

naringenin, luteolin, and thymonin, and has been shown to

protect and increase the percentage of healthy fats found in

cell membranes. As reported by the George Mateljan

Foundation:12 “In particular, the amount of DHA (docosahexaenoic acid, an

omega-3 fatty acid) in brain, kidney, and heart cell membranes was increased after

dietary supplementation with thyme.”

Thyme is also nutrient dense, containing vitamin C, vitamin A,

iron, manganese, copper, and dietary fiber. When used in

cooked dishes, thyme may also help inhibit glycation and the

formation of dangerous advanced glycation end products (AGEs)

in your food, making thyme a potential preventer of heart

disease and premature aging. Due to thyme oil’s antibacterial,

antispasmodic, antirheumatic, expectorant, hypertensive, and

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calming properties, it also has a long list of topical uses,

including:

Traditional uses of thyme

Home remedy – Thyme oil is used to relieve and treat

problems like gout, arthritis, wounds, bites, and sores,

water retention, menstrual and menopausal problems,

nausea and fatigue, respiratory problems (like colds),

skin conditions (oily skin and scars), athlete’s foot,

hangovers, and even depression.

Aromatherapy oil – The oil can be used to stimulate the

mind, strengthen memory and concentration, and calm the

nerves.

Hair product – It is said that thyme oil can prevent hair

loss. It is used as a treatment for the scalp and is

added to shampoos and other hair products.

Skin product – Thyme oil can help tone aged skin and

prevent acne outbreaks.

Mouthwashes and herbal rinses – Like peppermint,

wintergreen, and eucalyptus oils, thyme oil is used to

improve oral health.

Insecticide/insect repellent – Thyme oil can keep insects

and parasites like mosquitoes, fleas, lice, and mothus

away

Medicinal uses

Thyme has antiseptic qualities that make it useful for a

mouthwash and to combat tooth decay. Its antiseptic qualities

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also make it useful in cases of anemia, bronchial ailments,

and intestinal problems, as well as a skin cleanser. It has

been known for anti-fungal properties that can be used to

treat athlete’s foot and has anti-parasitic properties that

are useful against lice, scabies, and crabs. It has shown

useful for colic, excess gas, sore throats, and as a hangover

remedy. Thyme also proves beneficial as an expectorant to

loosen and expel mucous.

Make a poultice by mashing the leaves into a paste for use on

skin inflammations and sores. Using thyme for an anti-fungal

or parasitic agent can be done by mixing four ounces of fresh

thyme to a pint of vodka or fresh vinegar with “the mother”

still in the container (the mother is the vinegar starter).

Crush the thyme leaves slightly and let sit 12 hours or

overnight. Or buy the essential oil and use it sparingly.

Apply to the affected area.

For gastric issues or bronchitis, make a tea of 1 teaspoon

leaves to each cup of boiling water and steep 10-15 minutes.

Use only once a day. Add small amounts of honey to sweeten, if

desired.

Infusions of thyme have also been useful in soothing and

healing muscle spasms and skin irritations. Thyme also

contains a compound that is helpful in preventing blood clots.

Aromatherapy of the essential oil of thyme has been used to

boost the mind, body, and spirit. Vapors of thyme’s essential

oil have been effective for treating respiratory infections.

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Thyme oil or infusion can be added to bath water to aid

bronchial problems and sooth rheumatism.

Burning thyme can repel insects and a dilution of thyme oil

can be used externally as a deodorant and antiseptic that will

prevent mildew. An ointment made with thyme has been used to

treat warts. And some have said that it is useful to help new

mothers to expel the afterbirth. Thyme ointment can be made

from its leaves to sooth the discomfort associated with gout

and killing worms internally.

Thyme has many helpful actions. It has been used as an

antiseptic, anodyne, disinfectant, antitussive, anti-

inflammatory, rubefacient, demulcent, apertif, carminative,

diaphoretic, depurative, digestive, diuretic, expectorant,

fungicide, nervine, pectoral, sedative, stimulant, and

vermifuge.

As I previously mentioned, thyme oil is an effective natural

agent against nasty bacterial strains. A study9 presented at

the Society for General Microbiology's spring conference in

Edinburgh pointed out that essential oils may be efficient and

affordable alternatives to antibiotics in the battle against

resistant bacteria.

Among the essential oils tested, cinnamon oil and thyme oil

were found to be the most successful against various

Staphylococcus species, including the dreaded MRSA.  Researchers

said that this can help lower antibiotic use and minimize the

formation of new resistant strains of microorganisms.

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Oil of thyme can also function as a decontaminant for food

products. As shown in Food Microbiology, both basil and thyme

essential oils exhibited antimicrobial properties against

Shigella sonnei and Shigella flexneri that may contaminate food. The

compounds thymol and carvacrol in thyme oil demonstrated this

benefit.10

Furthermore, thyme oil can be used as a preservative against

spoilage and several foodborne germs that can contribute to

health problems. It is effective against other forms of

bacteria like Salmonella, Enterococcus, Escherichia, and Pseudomonas

species.11

Other reports also show that oil of thyme has anti-

inflammatory properties. In a research published in the Journal

of Lipid Research,12 six essential oils including thyme oil showed

the ability to suppress the inflammatory cyclooxygenase-2

(COX-2) enzyme in the same manner as the antioxidant

resveratrol does. It was noted that the chemical constituent

carvacrol was responsible for this effect.

The same study also noted that thyme and the other essential

oils activated peroxisome proliferator-activated receptors

(PPARs), which help suppress COX-2 expression.

In addition to these, significant health benefits of thyme oil

include:14

Helps reduce symptoms of chronic fatigue syndrome

Stimulates menstrual flow

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Increases circulation and elevates low blood pressure

Triggers the removal of waste that may lead to cellulite

Eases nervousness and anxiety

Helps fight insomnia

Eliminates bad breath and body odor

6.Chamomile (Matricaria chamomilla L.)

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Some of the secondary metabolites in the plant.

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Chamomile is most popular in tea form for use to calm

upset stomach and help support restful sleep. Germany’s

Commission E (a government organization) has even

approved the use of chamomile for reducing swelling on

your skin and fighting bacteria. Chamomile is a powerful

anti-inflammatory that also has antibacterial, anti-

spasmodic, anti-allergenic, muscle relaxant, and sedative

properties. It is used to treat psoriasis, eczema,

chickenpox, diaper rash, slow-healing wounds, abscesses,

and gum inflammation, and according to Herb Wisdom may

also be useful for the following conditions:

“The oil serves many medicinal purposes, but one of the best-documented

uses is for relaxation. The oil has a calming effect on people, and can be used

to help induce sleep, ease frayed nerves, and promote a general sense of

calmness and well being. It is great for those with nervousness or anxiety

problems. Aside from having mental calming properties, chamomile is also

good at relaxing sore muscles and tight joints.

It can ease menstrual cramps and back aches, as well as relax the digestive

system to ease upset stomach or indigestion issues. When applied topically to

the skin, it soothes redness and irritation. For this reason, it is a common

ingredient in skincare. It also eliminates itchiness and is good for those with

allergic reactions. Sometimes chamomile is used on rashes. Because of its

anti-inflammatory properties, it can work to take down swelling caused by

rashes or skin irritants.”

Traditional uses

Traditionally, chamomile has been used for centuries as an

anti-inflammatory, antioxidant, mild astringent and healing

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medicine . As a traditional medicine, it is used to treat

wounds, ulcers, eczema, gout, skin irritations, bruises,

burns, canker sores, neuralgia, sciatica, rheumatic pain,

hemorrhoids, mastitis and other ailments. Externally,

chamomile has been used to treat diaper rash, cracked nipples,

chicken pox, ear and eye infections, disorders of the eyes

including blocked tear ducts, conjunctivitis, nasal

inflammation and poison ivy. Chamomile is widely used to treat

inflammations of the skin and mucous membranes, and for

various bacterial infections of the skin, oral cavity and

gums, and respiratory tract. Chamomile in the form of an

aqueous extract has been frequently used as a mild sedative to

calm nerves and reduce anxiety, to treat hysteria, nightmares,

insomnia and other sleep problems. Chamomile has been valued

as a digestive relaxant and has been used to treat various

gastrointestinal disturbances including flatulence,

indigestion, diarrhea, anorexia, motion sickness, nausea, and

vomiting . Chamomile has also been used to treat colic, croup,

and fevers in children .It has been used as an emmenagogue and

a uterine tonic in women. It is also effective in arthritis,

back pain, bedsores and stomach cramps.

Medicinal uses

Anti-inflammatory and antiphlogistic properties

The flowers of chamomile contain 1–2% volatile oils including

alpha-bisabolol, alpha-bisabolol oxides A & B, and matricin

(usually converted to chamazulene and other flavonoids which

possess anti-inflammatory and antiphlogistic properties . A

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study in human volunteers demonstrated that chamomile

flavonoids and essential oils penetrate below the skin surface

into the deeper skin layers . This is important for their use

as topical antiphlogistic (anti-inflammatory) agents. One of

chamomile’s anti-inflammatory activities involve the

inhibition of LPS-induced prostaglandin E(2) release and

attenuation of cyclooxygenase (COX-2) enzyme activity without

affecting the constitutive form, COX-1 .

Anticancer activity

Most evaluations of tumor growth inhibition by chamomile

involve studies with apigenin which is one of the bioactive

constituents of chamomile. Studies on preclinical models of

skin, prostate, breast and ovarian cancer have shown promising

growth inhibitory effects .In a recently conducted study,

chamomile extracts were shown to cause minimal growth

inhibitory effects on normal cells, but showed significant

reductions in cell viability in various human cancer cell

lines. Chamomile exposure induced apoptosis in cancer cells

but not in normal cells at similar doses .The efficacy of the

novel agent TBS-101, a mixture of seven standardized botanical

extracts including chamomile has been recently tested. The

results confirm it to have a good safety profile with

significant anticancer activities against androgen-refractory

human prostrate cancer PC-3 cells, both in vitro and in vivo

situation .

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Common cold

Common cold (acute viral nasopharyngitis) is the most common

human disease. It is a mild viral infectious disease of the

upper respiratory system. Typically common cold is not life-

threatening, although its complications (such as pneumonia)

can lead to death, if not properly treated. Studies indicate

that inhaling steam with chamomile extract has been helpful in

common cold symptoms; however, further research is needed to

confirm these findings.

Cardiovascular conditions

It has been suggested that regular use of flavonoids consumed

in food may reduce the risk of death from coronary heart

disease in elderly men . A study assessed the flavonoid intake

of 805 men aged 65–84 years who were followed up for 5 years.

Flavonoid intake (analyzed in tertiles) was significantly

inversely associated with mortality from coronary heart

disease and showed an inverse relation with incidence of

myocardial infarction. In another study , on twelve patients

with cardiac disease who underwent cardiac catheterization,

hemodynamic measurements obtained prior to and 30 minutes

after the oral ingestion of chamomile tea exhibited a small

but significant increase in the mean brachial artery pressure.

No other significant hemodynamic changes were observed after

chamomile consumption. Ten of the twelve patients fell into a

deep sleep shortly after drinking the beverage. A large, well-

designed randomized controlled trial is needed to assess the

potential value of chamomile in improving cardiac health.57

Colic/Diarrhoea conditions

An apple pectin-chamomile extract may help shorten the course

of diarrhea in children as well as relieve symptoms associated

with the condition . Two clinical trials have evaluated the

efficacy of chamomile for the treatment of colic in children.

Chamomile tea was combined with other herbs (German chamomile,

vervain, licorice, fennel, balm mint) for administration. In a

prospective, randomized, double-blind, placebo-controlled

study, 68 healthy term infants who had colic (2 to 8 weeks

old) received either herbal tea or placebo (glucose,

flavoring). Each infant was offered treatment with every bout

of colic, up to 150 mL/dose, no more than three times a day.

After 7 days of treatment, parents reported that the tea

eliminated the colic in 57% of the infants, whereas placebo

was helpful in only 26% (P<0.01). No adverse effects with

regard to the number of nighttime awakenings were noted in

either group . Another study examined the effects of a

chamomile extract and apple pectin preparation in 79 children

(age 0.5–5.5 y) with acute, non-complicated diarrhea who

received either the chamomile/pectin preparation (n = 39) or a

placebo (n = 40) for 3 days. Diarrhea ended sooner in children

treated with chamomile and pectin (85%), than in the placebo

group (58%) . These results provide evidence that chamomile

can be used safely to treat infant colic disorders of

chamomile in managing diabetes.

58

Qualitative Test for TanninsThere are three groups of methods for the analysis of tannins:

precipitation of proteins or alkaloids, reaction with phenolic

rings, and depolymerisation. (Augustine 1992)

Goldbeater's skin test

When goldbeater's skin or ox skin is dipped in HCl, rinsed in

water, soaked in the tannin solution for 5 minutes, washed in

water, and then treated with 1% FeSO4 solution, it gives a blue

black colour if tannin was present.

Ferric chloride (FeCl3) test

It is rather a test for phenolics in general. Powdered plant

leaves of the test plant (1.0 g) are weighed into a beaker and

10 ml of distilled water are added. The mixture is boiled for

five minutes. Two drops of 5% FeCl3 are then added. Production

of a greenish precipitate was an indication of the presence of

tannins. Alternatively, a portion of the water extract is

diluted with distilled water in a ratio of 1:4 and few drops

of 10% ferric chloride solution is added. A blue or green

colour indicates the presence of tannins (Evans, 1989).

Other methods

The hide-powder method is used in tannin analysis

for leather tannin and the Stiasny method for wood adhesives.

Statistical analysis reveals that there is no significant

relationship between the results from the hide-powder and the

Stiasny methods.

59

Hide-powder method

400 mg of sample tannins are dissolved in 100 ml of distilled

water. 3 g of slightly chromated hide-powder previously dried

in vacuum for 24h over CaCl2 are added and the mixture stirred

for 1 h at ambient temperature. The suspension is filtered

without vacuum through a sintered glass filter. The weight

gain of the hide-powder expressed as a percentage of the

weight of the starting material is equated to the percentage

of tannin in the sample.

Stiasny's method

100 mg of sample tannins are dissolved in 10 ml distilled

water. 1 ml of 10M HCl and 2 ml of 37% formaldehyde are added

and the mixture heated under reflux for 30 min. The reaction

mixture is filtered while hot through a sintered glass filter.

The precipitate is washed with hot water (5x 10 ml) and dried

over CaCl2. The yield of tannin is expressed as a percentage of

the weight of the starting material

60

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