1206

12(2): Medicinal and poisonous plants 2

Nymphaea nouchali Burm.f.

Fl. indica: 120 (1768).

NYMPHAEACEAE

2n = 28, 56, 84

Nymphaea stellata Willd. (1800).

Water lily, lotus lily (En). Nénuphar bleu (Fr). Indonesia: tunjung. Malaysia: kelipok, teratai kechil. Philippines: lauas, pulau (Tagalog), talailo (Bisaya). Cambodia: rum' châng, pralit, mum phlong. Laos: hua bua, bwà khiiz bèèz, bauna neai. Thailand: bua-phan, bua khaap (central), nirobon (Bangkok). Vietnam: s[us]ng lam, b[oo]ng s[us]ng, c[ur] s[us]ng.

Nymphaea nouchali is distributed from Africa to India, and throughout South-East Asia to Australia, both wild and cultivated.

Especially the rhizomes, but also the other parts of Nymphaea nouchali (and other Nymphaea species), are considered astringent and tonic in South-East Asia, and a decoction is given for diarrhoea. In Vietnam, the rhizomes are also used for treating backache and stomach-ache, and in Cambodia for treating colic. In India, the powdered rhizome is prescribed as a demulcent for piles, and also for dysentery and dyspepsia. An infusion of the fresh rhizomes is considered emollient and diuretic, and used for blennorrhagia and infections of the urinary tract.
In the Philippines, the slightly bitter juice of the leaves and petioles is used for gonorrhoea. The juice possesses mildly narcotic properties, and is rubbed on the forehead and temples to produce sleep. In Cambodia, the juice from the leaves or the macerated leaves are an ingredient of a lotion applied to the skin for fever. In India and Thailand, the flowers are taken as a cardiotonic because of its astringent properties.
The rhizomes of Nymphaea nouchali are edible and rich in starch, like those of other Nymphaea species, though less appreciated than those of Nelumbo nucifera Gaertner (Nelumbonaceae, formerly in Nymphaeaceae). Seeds, young leaves and petioles of many other Nymphaea species are eaten as well. Nymphaea is often consumed as a famine food, but especially in Africa, it is part of the normal diet for certain tribes. The rhizomes are considered poisonous unless boiled.
In West Africa, the rhizome of Nymphaea lotus L. is sometimes chewed as a substitute for kola nut (Cola spp.). In India, the rhizomes of Nymphaea nouchali have been used for tanning purposes. Most Nymphaea species, including Nymphaea nouchali, are widely cultivated in the tropics as an ornamental.

Nymphaea nouchali is widely cultivated and traded as an ornamental. No statistics on medicinal trade are available.

All parts of Nymphaea nouchali, except for the seeds, contain the alkaloid nymphaeine. This alkaloid is toxic to frogs and produces tetanus-like symptoms. Alcoholic extracts of the rhizome, containing the alkaloid, have a mild sedative and spasmolytic action. They do not significantly depress the heart; in large doses though, they have a paralysing effect on the medulla. Another alkaloid, coclaurine, was also found in the leaves and stem.
Nymphaea species contain several flavonoids e.g. kaempferols, quercetins and myricetins, especially in the flowers, and also a glycoside, nymphalin, which has a digitalis-like action.
The extract from the rhizomes did not cause a significant growth of mammary glands, when injected into immature female mice at 2 g/day for 5 days.
Nymphaea lotus contains the alkaloids nupharine, nymphaeine, nelombine and nupharidine, which are respiratory excitants. An overdose may cause death by lung poisoning, as has been seen in mice, dogs and fish. An extract of the leaves of Nymphaea pubescens Willd. was screened for its antifungal activity and caused 85% inhibition of spore germination in Fusarium solani, but not in Drechslera spicifera.

Nelumbo nucifera has similar medicinal, culinary and ornamental use as Nymphaea species.

A perennial, aquatic herb, rhizome cone-like, tuberous. Leaves simple, ovate-orbicular, 10—30 cm x 8—25 cm, floating, base incised, cordate or hastate, lobes (nearly) overlapping, blade narrowly peltate, margins entire, sinuate, dentate or lobulate, upper side green, glabrous, lower side green, red or purple or spotted purple, mostly glabrous, sometimes finely pubescent, veins palmate; petiole long; stipules present. Flowers solitary, 8—18 cm in diameter, held 5—20 cm above the water, pedicel up to 1.5 m long, reddish, spongy; sepals 4, adnate at base to base of receptacle, inside the same colour as corolla; petals 10—35, many-seriate, the inner diminishing in size, normally blue, but also white, purplish blue or pinkish, slightly fragrant; stamens numerous, the outer with broad petaloid filaments; receptacle with cup-shaped apex, carpels 10—16, immersed, forming a numerous-celled syncarpous ovary, stigmas radiate, yellow. Fruit a depressed globose syncarp, berry-like, 2—4 cm in diameter, spongy, ripening under water, irregularly dehiscent, seeds numerous. Seed narrowly ovoid, 1—1.5 mm long, greyish-white, with longitudinal ridges, floating due to air-containing sack-like, pulpy aril, perisperm present. Seedling with only one cotyledon.

Nymphaea nouchali can be found flowering throughout the year. The flowers open during the day, but some other Nymphaea flower during the night. Flowers are generally protogynous, and first-day flowers open less wide than on later days. Insect pollinators are attracted by the colour and the odour of the flowers and include mostly Hymenoptera, although Coleoptera and Diptera may also be present. Pollen-covered insects which visit first-day flowers effect cross-pollination. The flowers open during a period of 3—4 days. Natural hybridization occurs wherever several species grow together in the same pond; the hybrids may be fertile or sterile. When plants become overcrowded, flowers are smaller and fewer and foliage is lifted out of the water. Dense infestation can be cleared out of ponds manually or with herbicides, after which grass carps can be introduced to keep the number of plants down.

Nymphaea is a taxonomically difficult group, consisting of 35—45 species, and occurring widely in temperate and tropical regions throughout the world. Five subgenera are recognized, and only the subgenus from the New World has been revised thoroughly. Nymphaea nouchali belongs to subgenus Brachyceras, which has incompletely fused carpels. There is considerable confusion about the status of Nymphaea nouchali, Nymphaea caerulea Savigny and Nymphaea capensis Thunb., but the last 2 species are nowadays often considered as varieties of Nymphaea nouchali. Five varieties are distinguished in Africa, of which (at least) 2 also occur in South-East Asia. Var. caerulea (Savigny) Verdc. (synonyms Nymphaea caerulea, Nymphaea capensis) has leaves with entire to slightly undulate margins, while var. zanzibariensis (Casp.) Verdc. has lobulate margins, and is recorded as nocturnal and homogamous.
Formerly Nymphaea lotus was considered to occur both in Asia and Africa, but the Asian plants are now referred to as Nymphaea pubescens. The true relationships between the African and Asian taxa is still unclear, however, and difficult to elucidate from herbarium material. The size and form of the leaves and flowers can vary widely, even in one locality.
The name sacred lotus has often been misapplied to several species. In effect, the Egyptian sacred lotus is Nymphaea lotus, while Nelumbo nucifera (synonym Nelumbium nelumbo (L.) Druce) is the Indian sacred lotus.

Nymphaea nouchali is common throughout its distribution area, and is found in shallow ponds, ditches and lakes up to 500 m altitude.

Nymphaea nouchali is propagated by seed and by division, or by pieces of rhizome with a sprouting eye. Some Nymphaea species produce viviparous plantlets in the leaf-blade axil, by which they can be propagated as well. Seed can be gathered after about 10 days of immersion, or immediately when it resurfaces, and can be planted into finely graded propagating mix, with about 2.5 cm of water. When the first floating leaves appear the water level can gradually be raised.

Leaf spot is caused by Cercospora spp. and Ovularia spp. and affected leaves need to be removed quickly in order to prevent spreading of the disease. Crown rot can be a serious problem, and seems to be a stress-related, multifactorial syndrome. Several fungi and bacteria have been identified, but no satisfactory solution has yet been found. Nymphaea nouchali can be extensively damaged by caterpillars of the moths Nymphula stagnata and Nymphaea nympheata, which feed on the leaves and flowers.

Leaves, flowers and seeds of Nymphaea nouchali are harvested from the water surface from land or by boat, but rhizomes are more difficult to dig up. This is sometimes done by pulling the whole plant up by the leaves. In periodically flooded areas, rhizomes are harvested when the water level has dropped.

In Sri Lanka, Nymphaea nouchali has been cultivated for its edible rhizomes in rice fields during the monsoon period, and up to 2500 kg/ha can be harvested annually.

The parts of Nymphaea nouchali harvested are normally used fresh.

Nymphaea nouchali is widespread and common throughout South-East Asia, and therefore certainly not endangered. There are no known breeding programmes for medicinal purposes.

Some interesting information is available on constituents displaying biological activity from Nymphaea species, including Nymphaea nouchali. However, more research will be needed for instance on toxicological aspects, in order to fully evaluate their possible potential.

Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. Revised reprint. Vol. 2. Ministry of Agriculture and Co-operatives, Kuala Lumpur, Malaysia. pp. 1592-B1593.
Conn, B.J., 1995. Nymphaeaceae. In: Conn, B.J.: Handbooks of the flora of Papua New Guinea. Vol. 3. Melbourne University Press, Melbourne, Australia. pp. 192—202.
Fossen, T., Larsen, A., Kiremirec, B.T. & Andersen, O.M., 1999. Flavonoids from blue flowers of Nymphaea caerulea. Phytochemistry 51(8): 1133—1137.
Quisumbing, E., 1978. Medicinal plants of the Philippines. Katha Publishing Co., Quezon City, the Philippines. pp. 289—290.
Reddy, V.K. & Reddy, S.M., 1987. Screening of indigenous plants for their antifungal principle. Pesticides (Bombay) 21(9): 17—18.
Verdcourt, B., 1989. Nymphaeaceae. In: Polhill, R.M. (Editor): Flora of Tropical East Africa. A.A. Balkema, Rotterdam, the Netherlands & Brookfield, United Kingdom. pp. 1B-12.

[704] Mukherjee, K.S., Bhattacharya, P., Mukherjee, R.K. & Ghosh, P.K., 1986. Chemical examination of Nymphaea stellata Willd. Journal of the Indian Chemical Society 63(5): 530—531.
[739] Nguyen Van Duong, 1993. Medicinal plants of Vietnam, Cambodia and Laos. Mekong Printing, Santa Ana, California, United States. 528 pp.
[838] A revised handbook to the flora of Ceylon (various editors), 1980—2000. Volume 1—9. Amerind Publishing Co., New Delhi, India. Volume 10—14. A.A. Balkema, Rotterdam, the Netherlands.
[914] Siemonsma, J.S. & Kasem Piluek (Editors), 1993. Plant Resources of South-East Asia No 8. Vegetables. Pudoc Scientific Publishers, Wageningen, the Netherlands. 412 pp.
[1068] Wiersema, J.H., 1987. A monograph of Nymphaea subgenus Hydrocallis (Nymphaeaceae). Systematic Botany Monographs 16. 112 pp.

G.H. Schmelzer

Schmelzer, G.H., 2001. Nymphaea nouchali Burm.f.. In: van Valkenburg, J.L.C.H. and Bunyapraphatsara, N. (Editors): Plant Resources of South-East Asia No 12(2): Medicinal and poisonous plants 2. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea