Introduction
Plants are the reservoirs of a
large number of imperative organic compounds and they have long been used as the
sources of medicines. Dependence on plants is prevalent in developing countries
where the traditional herbal medicine plays a major role in health care and in
the treatment of many infectious diseases. The rural population of a country is
more disposed to traditional ways of treatment because of its easy availability
and cheaper cost.
Herbal therapies although still
an unwritten science is well established in some cultures and tradition and have
become a way of treatment in almost 80% of the people in rural areas, especially
those in Asia, Latin America and Africa.
Natural products of folk
medicine have been used for centuries in every culture throughout the world.
Scientists and medical professionals have Intl. J. Noni Res. 2005, 1(1) 1 shown
increased interest in this field as they recognized the true health benefits of
these remedies. While searching for food, the ancient found that some foods had
specific properties of relieving or eliminating certain diseases and maintaining
good health. It was the beginning of herbal medicine. The same story occurred in
Polynesia. Among the medicinal plants discovered by the ancestors of
Polynesians, Noni (Morinda citrifolia) is one of the important traditional folk
medicinal plants that have been used for over 2000 years in Polynesia. It has
been reported to have a broad range of therapeutic and nutritional value. The
ancestors of Polynesians are believed to have brought many plants with them, as
they migrated from Southeast Asia 2000 years ago (Tabrah and Eveleth, 1966;
Gerlach, 1996). Of the 12 most common plants they brought, Noni was the second
most popular plant used in herbal remedies to treat various common diseases and
to maintain overall good health (Krauss, 1993; Gerlach, 1996).
Morinda citrifolia fruit has long
history of use as a food in tropical regions throughout the world. Documentation
of the consumption of the fruit as a food source precedes the twentieth century.
Captain James Cook of the British Navy noted in the late 1700’s that the fruit
was eaten in Tahiti. An 1866 publication in London explained that M. citrifolia
fruit was consumed as a food in the Fiji Islands. Later publications described
the use of this fruit throughout the Pacific Islands, Southeast Asia, Australia
and India. In Roratonga, the natives often ate the fruit. Australian Aborigines
were very much fond of this fruit. In Samoa, Noni fruit was common fare and in
Burma it was cooked in curries or eaten raw with salt. In 1943, Merrill
described M. citrifolia L. as an edible plant in a technical manual of edible
and poisonous plants of the Pacific Islands, in which the leaves and fruits were
used as emergency food. In 1992, Abbott reported that Noni had been used as
food, drink, medicine and dye.
The medicinal properties of M.
citrifolia such as anticancer, antitumour, anti-diabetics, antiageing,
antimicrobial, etc. have fully been studied scientifically in abroad as a result
several commercial products of Noni are available at present.
Noni is commonly referred to the
species M. citirfolia and is also called as Indian Mulberry. It is also known in
different names locally as Cheese Fruit, Forbidden Fruit, Headache Tree, Hog
Apple, Mona, Mora de la India, Nino, Nona, Nono, Nonu, Nuna, Pain Bush, Pain
Killer Tree, Pinuela, Wild Pine, etc. in various parts of the world. Noni is an
evergreen tree found growing in open coastal regions at sea level (Fig. 1) and
in forest areas up to about
1300 feet above sea level. It is often found
growing along lava flows. Noni is identifiable by its straight trunk, large,
bright green and elliptical leaves, white tubular flowers and its distinctive,
ovoid, “grenade-like” yellow fruit.
The
fruit can grow in size up to 12 cm or more and has a lumpy surface covered by
polygonal-shaped sections (Fig. 2). The seeds, which are triangular shaped and
reddish brown, have an air sac attached at one end, which makes the seeds
buoyant. The mature Noni fruit has a foul taste and odour.
Distribution of Morinda
The genus Morinda is
present worldwide predominantly in tropical countries. It occurs in Africa,
Australia, Barbados, Cambodia, Caribbean, Cayman Islands, Cuba, Dominican
Republic, El Salvador, Fiji, Florida, French West Indies, Guadeloupe, Guam,
Haiti, Hawaii, India, Jamaica, Java, Laos, Malaysia, Marquesas Islands,
Philippines, Polynesia, Puerto Rico, Raratonga, Samoa, Seychelles, Solomon
Islands, Southeast Asia, St. Croix, Surinam, Tahiti, Thailand, Tonga, Trinida
and Tobago and Vietnam.
Survey of Morinda in south India indicated that
12 different species or varieties of Morinda are distributed throughout
TamilNadu and Kerala. However, the species M. tinctoria is present abundantly in
most parts of TamilNadu and in some parts of Kerala. To our surprise, M.
citrifolia is not recorded in the study area of TamilNadu whereas it is
profusely distributed in most part of the Kerala especially coastal region and
also in the Mangalore
area of Karnataka. Recently we recorded the
presence of an unidentified Morinda species with large and leathery leaves in
the Dhandakaranya forest area of Malkanagiri district in Orissa.
Taxonomy
of Morinda
Family: Rubiaceae
Common name: Nuna, Noni, Cheese fruit,
Koonjerung, Tokoonja, Great Morinda.
Derivation
of the name Morinda: From Latin Morus, Mulberry and indicus, Indian
referring to the similarity of the fruit to the Mulberry, Morus indica. General
description of the genus Morinda
Plant: Woody vines, lianas,
shrubs, medium-sized trees or tall canopy trees; raphides present; auciliary
thorns absent.
Stipules: Interpetiolar, free at base or
interpetiolar, connate at base or sheathing (not splitting on one side), oblong
or ligulate, spatulate or bifid, sheathing at base, with two small (non-foliose)
lobes each side, persistent. Leaves: Opposite or whorled, rarely ternate, 3 per
node, long or shortpetiolate; blades ovate, broadly elliptic, oblong or
oblanceolate, chartaceous or stiffly chartaceous; foliar pellucid glands absent;
domatia sparse or dense tufts of hairs or absent.
Inflorescence:
Axillary or terminal, simple panicle or umbellate heads, not frondose, globose,
not subtended by bracts.
Flowers: Bisexual,
protandrous.
Calyx: Tubular, urceolate or hemispheric, extremely
reduced, with small lobes or short tubular, caducous; lobes absent (calyx
truncate or undulate) or 4 to 7, broadly triangular, minute. Calycophylls
absent.
Corolla: Tube, more or less funnel shaped, hypocrateriform
or narrowly infundibuliform, actinomorphic, white to cream-white; tube
externally glabrous, internally glabrous or pubescent; without a pubescent ring
inside; orifice annular thickening absent; lobes 4 to 7, valvate in bud,
lanceolate or oblong, margin entire, obtuse or acute at apex. Stamens: Alternate
to the corolla lobes, included, partially exerted (only tips exerted) or exerted
just beyond the corolla; anthers narrowly oblong or elongate, round at base,
with acuminate extensions at apex, dehiscing by longitudinal slits, dorsifixed
near the middle; filaments attached at the middle of the corolla tube, free at
base, slender, long, shorter than corolla tube, equal,
glabrous.
Style: Exerted just beyond the corolla, terete
throughout, not fleshy or terete, not fleshy, capitate, glabrous; lobes absent
or 2, ovate, oblong or linear, stigmatic surface located at style apex.
exert
Ovary: Inferior, 2- or 4- locular, narrowly obovoid;
placenta reduced, ovules basally inserted, 1 per locule.
Fruit:
Densely clustered globose syncarp, fleshy.
Seeds: Vertical,
medium-sized, ovoid to obovoid or reniform; wings absent.
Chemical properties of
Morinda
A number of major compounds have
been identified in the Noni plant such as scopoletin, octoanoic acid, potassium,
vitamin C, terpenoids, alkaloids, anthraquinones (such as nordamnacanthal,
morindone, rubiadin, andrubiadin- 1-methyl ether, anthraquinone glycoside),
β-sitosterol, carotene, vitamin A, flavones glycosides linoleic acid, alizarin,
amino acids, acubin, L-asperuloside, caproic acid, caprylic acid, ursolic acid,
rutin and a putative proxeronine. (Levand and Larson, 1979; Farine et al., 1996;
Peerzada et al., 1990;
Budhavari et al., 1989; Moorthy and Reddy,
1970; Daulatabad et al., 1989; Balakrishnan et al., 1961; Legal et al., 1994;
Singh and Tiwari, 1976; Simonsen, 1920; Heinicke, 1985). The dominant substances
in the fruit are fatty acids, while the roots and bark contain anthraquinone.
The seed of M. citrifolia contains 16.1% Oil. The main fatty acid components of
the oil were linoleic (55%), Oleic (20.5%), Palmitic (12.8%), Ricinoleic (6.8%)
and Stearic (4.9%) (Dualatabad et al., 1989; Seidemann, 2002). A research group
led by Chi-Tang Ho at Rutges University in the USA is searching for new novel
compounds in the Noni plant. They have successfully identified several new
flavonol glycosides, and iridoid glycoside from the Noni leaves, trisaccharide
fatty acid ester, rutin and an asperolosidic acid from the fruit. Two novel
glycosides and a new unusual iridoid named citrifoliniside have been shown to
have inhibiting effect on AP-1 trans activation and cell transformation in the
mouse epidermal JB6 cell lines (Wang et al., 1999; Sang et al., 2001a and b; Liu
et al., 2001; Wang et al., 2000). Further, 23 different phytochemicals were
found in Noni besides, 5 vitamins and 3 minerals (Duke, 1992).
General
use of Morinda
The species of Morinda especially M. citrifolia
has been reported to have a broad range of health benefits for cancer,
infection, arthritis, asthma, hypertension, and pain (Whistler, 1992). The
roots, stems, bark, leaves, flowers, and fruits of the Noni are all involved in
various combinations in almost 40 known and recorded herbal remedies
(Bruggnecate, 1992).
Additionally, the roots were used to produce a
yellow or red dye for tapa cloths and fala (mats), while the fruit was eaten for
health and food (Aragones et al., 1997). Medicinal use of Morinda The
Polynesians utilized the whole Noni plant for herbal remedies. The fruit juice
is in high demand in alternative medicine for different kinds of illnesses such
as arthritis, diabetes, high blood pressure, muscle aches and pains, menstrual
difficulties, headaches, heart disease, AIDS, cancers, gastric ulcer, sprains,
mental depression, senility, poor digestion, arteriosclerosis, blood vessel
problems, and drug addiction. Scientific evidence of the benefits of the Noni
fruit juice is limited but there is some anecdotal evidence for successful
treatment of colds and influenza (Solomon, 1999). Allen and London (1873)
published one of the earliest articles on the medicinal benefits of Noni in
which they reported the ethnobotanical properties of Noni and the use of fruit.
Abbott (1985), a former botanical chemist at the University of Hawaii, stated
the use of Noni for diabetes, high blood pressure, cancer, and many other
illnesses (Abbott, 1985; Dixon et al., 1999). Noni was a traditional remedy used
to treat broken bones, deep cuts, bruises, sores and wounds (Bushnell et al.,
1950). Morton (1992) gave numerous references for medicinal uses of Noni. In
addition, Polynesians are reported to treat breast cancer and eye problems.
