Argemone mexicana (PROSEA)
- Protologue: Sp. pl. 1: 508 (1753).
- Family: Papaveraceae
- Chromosome number: 2n= 28
- Mexican poppy, prickly poppy, yellow thistle (En).
- Argémone, pavot épineux, pavot du Mexique (Fr)
- Indonesia: celangkringan, druju (Javanese)
- Malaysia: chelang keringan
- Philippines: kachumba, kasubang-aso (Iloko), diluariu (Tagalog)
- Thailand: fin naam (Bangkok)
- Vietnam: gai cua, mùi cua, cà gai hoa vàng.
Origin and geographic distribution
Argemone L. originates from tropical America and comprises 6-9 species. A. mexicana is native in Mexico and the West Indies, but has become pantropical as an ornamental and a weed. It is naturalized in many Asian countries, from India, Indo-China to Taiwan, and southwards through Peninsular Malaysia, Java, the Lesser Sunda Islands, Sulawesi, to the Moluccas and the Philippines.
A. mexicana is not widely used in South-East Asia or Indo-China; the main users are people from India. In Vietnam though, the roots are sometimes used for rheumatism, while in the Philippines they are used as an abortifacient.
A. mexicana is highly esteemed as a medicinal plant throughout tropical America. The roots, leaves and seeds are registered officially in the Mexican pharmacopoeia. In tropical America, a decoction of the leaves is drunk for ailments of the spleen and liver, and for jaundice or whooping cough. An infusion of the young leaves or flowers is taken to relieve fever, cough and asthma. An infusion of the flowers is also taken before sleeping as a narcotic, to avoid insomnia, and given to teething children. In northern Venezuela, a decoction of the plant is employed as a sudorific, emmenagogue, vulnerary, depurative, emetic and treatment of epilepsy and cancer. In French Guyana, the root or stem is prescribed for vesicular calculus, as an eye-wash and a lotion for inflammations, as a mouth-wash for toothache and internally for gleet. In Mexico the seeds are considered an antidote to snake venom, whereas in French Guyana they are used as a cathartic and emetic.
In India, the root is used as an alterative, and an infusion is given to women to drink at the start of parturition, as well as being used against tapeworm. A decoction is also employed in chronic skin diseases. The latex is slightly corrosive and used to treat warts, but also for dropsy, jaundice and cutaneous infections. It is diuretic, relieves blisters, and heals ulcers and conjunctivitis. It is also rubbed on the body to relieve rheumatic pain. Mixed with milk it is given for leprosy. The seeds are laxative, emetic, nauseant, expectorant, and demulcent. They are useful in coughs and catarrhal affections of the throat and pulmonary mucous membrane, and in pertussis and asthma. Though they do not appear to possess any antispasmodic property, they have a distinct effect on asthma, apparently from their combined actions as nauseant, emetic, expectorant and demulcent. As their use is often accompanied by some degree of vomiting and nausea, as a laxative medicine they are more suited to some pulmonary affections than to other diseases. The seed oil is applied to herpes, indolent ulcers and externally for headaches. In West Africa, the plant is considered sedative, diuretic, cholagogue and anti-inflammatory.
The seed oil is toxic, causing intense pain all over the body, diarrhoea or constipation, and fever. The seeds have caused many fatalities in poultry, and the dried leaves are considered poisonous in fodder for cattle. In India, Mexico and the West Indies, the seed oil is sometimes used in the soap industry, or for illumination, whereas in Nigeria it is applied to preserve wood from termite attacks.
A. mexicana is sometimes cultivated as an ornamental.
Production and international trade
A. mexicana is only used locally and is not traded internationally, at least not in continental Asia or South-East Asia.
A. mexicana contains numerous alkaloids, biosynthetically derived from the amino acid phenylalanine, which belong to several alkaloid types e.g. the protopine type, the protoberberine type, the isoquinoline type, the benzyl(tetrahydro)isoquinoline type and the benzo[c]phenanthridine type. The total alkaloid fraction in the dried roots and stems is 0.25%, mainly consisting of protopine and berberine. Other alkaloids in the roots include coptisine, allocryptopine, chelerythrine and dihydro-chelerythrine. The stems and leaves also contain dihydro-palmatine, oxyhydrastinine, norsanguinarine, 6-acetonyl-dihydro-sanguinarin, 6-acetonyl-dihydro-chelerythrine, reticuline, thalifoline, acetyl-reframidine and muramine. The alkaloids argemonine (N-methylpavine), berberine, protopine, sanguinarine and dihydro-sanguinarine have been isolated from the seeds. In addition, the aerial parts also contain the aliphatic alcohols triacontan-11-ol and triacontane-6,11-diol.
The alkaloidal fraction from the seeds induced inhibition of spermatogenesis in dogs; isolated protopine induced inhibition of almost 100% when administered at 30 mg/kg for 70 days. Furthermore, the alkaloid fraction isolated from the roots led to a fall in blood pressure in anaesthetized dogs, and this action was not changed by atropine, antihistamines or adrenergic blocking agents. It also stimulated smooth muscles, antagonized the action of acetylcholine, histamine and serotonin. Its action on the uterus was similar to that of oxytocin. It showed a stimulating action on respiration, and antagonized barbiturate-induced respiratory depression. The methanol extract, a partially purified alkaloid fraction and some single compounds from the aerial parts were tested in a concentration-dependent assay to study morphine withdrawal (isolated guinea-pig ileum as a model). Both protopine and allocryptopine were found to reduce the morphine withdrawal significantly. The alkaloid fraction from the roots also showed anti-inflammatory activity in rabbits and rats.
Berberine, as a purified compound, has improving effects on the circulation in small doses, like a bitter. Overdose however, produces death by paralysis of the central nervous system. Other pharmacological effects of this compound, which can also be isolated from e.g. Arcangelisia and Tinospora species include spasmolytic, antibacterial and in some degree antifungal and antiprotozoal activity.
Protopine and sanguinarine show molluscicidal properties in Lymnacea acuminata , causing a significant decrease in protein levels, free amino acid, DNA and RNA in the nervous tissue, and a simultaneous increase in the rate of lipid peroxidation. Sanguinarine also showed inhibition (60%) of the transport of D-glucose in everted sacs of the small intestines of rats, at a dose of 1μM, and a dose-dependent inhibition of intestinal and hepatic enzyme Na+,K+-ATPase in a non-competitive manner.
The seeds of A. mexicana contain 36% of an orange-yellow oil, which was tested on hepatic xenobiotic metabolizing enzymes in albino rats in vivo. Following a single dose (10 ml/kg) or multiple intraparenteral doses (5 ml/kg) for 3 days, rats that had had a single dose exhibited a significant loss of hepatic cytochrome P-450 and cytochrome B5 contents and inhibition of aminopyrine-N-demethylase, aryl hydrocarbon hydroxylase and ethoxycoumarin-O-deethylase activities. The multiple dose treatment increased these effects, and caused a significant decrease in liver weight (40%). These results suggest that the oil causes auto-oxidative peroxidation of lipids.
The leaf extracts show some antifeedant activity against crop-eating and crop-sucking insects, including the cabbage webworm ( Crocidolomia binotalis ), the tobacco caterpillar ( Spodoptera litura ), the cotton aphid ( Aphis gossypii ) and also larvae of the mosquito Culex quinquefasciatus . The seed oil has a significant nematicidal effect on larvae of Meloidogyne incognita and M. javanica . An aqueous mixture of the oil (0.2%) applied to the soil or the leaves of okra ( Abelmoschus esculentus (L.) Moench) significantly reduced nematode infection in terms of root galling, root protein content, and nematode concentrations in roots and soil, thereby increasing okra growth. When sprayed on the leaves the effect was even more striking, showing the systemic effect of the spray. Dried plant extracts significantly reduced gall formation and hatching on seedlings of tomato and eggplant. Tomatoes treated with a leaf extract showed significantly less fruit rot caused by Aspergillus niger , in the presence of Drosophila busckii . A flower extract induced a high level of resistance to tomato virus X on the hypersensitive host Chenopodium amaranticolor (H.J. Coste & A. Reyn.) H.J. Coste & A. Reyn., for up to 96 days after leaf sprays. The petroleum and ethanol extracts also showed antibacterial activity in vitro against Bacillus subtilis , Escherichia coli and Streptococcus faecalis .
Aqueous leaf and flower leachates applied for 24 hours inhibit the germination and growth of many cultivated crops, such as tomato, cucumber, mustard, radish and pearl millet ( Pennisetum glaucum (L.) R.Br.).
Adulterations and substitutes
Ipecac (Psychotria ipecacuanha (Brot.) Stokes) is used as a substitute for the latex of A. mexicana in tropical America, because of its emetic properties. The seed oil of A. mexicana is an adulterant for mustard oil and sesame oil in India, but has been found to be the cause of epidemic oedema and glaucoma in humans.
- An annual, erect, branched, thistle-like herb, 30-100 cm tall, glabrous, containing yellow latex, stem pithy, with scattered prickles, taproot firm.
- Lower leaves crowded as in a rosette, petiole short, higher ones alternate, semi-amplexicaul, sessile, very variable in shape, sinuate-pinnatifid, 5-22 cm × 3-7 cm, white variegated along the main veins, bluish green elsewhere, prickles scattered along the margin and on the veins below.
- Inflorescence terminal, flowers solitary, sessile.
- Flowers 3-merous, surrounded by 3 foliaceous bracts; sepals 3, valvate, vaulted, horn just below apex acute, terete, with few prickles, caducous in anthesis; petals 6, obovate, strongly plicate in bud, 1.7-3 cm long, bright yellow; stamens many, free, 7-12 mm long, anthers 2.5 mm long; ovary ovate, with long soft bristles, 8-10 mm long, style very short, stigma 3-6-lobed, dark red.
- Fruit an ovoid capsule, 2.5-4 cm long, with rounded ribs, valves 3-6, dehiscing from the apex to about 1/3, replum miter-shaped, prickles sharp.
- Seeds globular, 1.5 mm in diameter, fine reticulate, black-brown, hilum prominent, pale.
- Seedling with epigeal germination; cotyledons long and narrow.
Growth and development
A. mexicana flowers and fruits throughout the year. The flowers open early in the morning, and then last for 2-3 days. Small stingless bees are the main pollinators.
Other botanical information
Several varieties of A. mexicana are recognized. In Australia, mostly var. ochroleuca (Sweet) Lindley occurs, which has pale yellow, stalked flowers, with a distinct style.
A. mexicana occurs mainly in regions with a pronounced dry season, on open waste ground, along roadsides, in fields as a weed and along railways, mostly at sea-level, but sometimes up to 3000 m altitude, locally abundant, but on the whole scattered.
Propagation and planting
A. mexicana is propagated by seed. The seed is light, has a waxy coat and is pitted, so that air can be trapped. It is thus favoured by wind and water dispersal. Seed production can be up to 18 000 to even 36 000 seeds per plant. A. mexicana seeds germinate best in moist soil with low to moderate temperatures (up to 25°C), but in some regions that can germinate throughout the year.
In vitro production of active compounds
Tissue culture of flowers, roots, stems, leaves or fruits of A. mexicana showed that most berberine was formed in the flowers, and that the precursor of berberine is tyrosine.
Diseases and pests
In some areas A. mexicana is attacked by bacterial wilt, caused by Xanthomonas papavericola , which periodically hampers its distribution.
The desired plant parts of A. mexicana are mostly harvested from wild-growing plants, but sometimes from cultivated ones as well.
Handling after harvest
Harvested material of A. mexicana is used fresh or dried.
Genetic resources and breeding
A. mexicana does not seem to be at risk of genetic erosion as it is a widely distributed weed. No breeding programmes for medicinal purposes are known to exist.
Several compounds of A. mexicana display interesting pharmacological effects as purified compounds, making further research is desirable. A. mexicana might be of interest as a natural source of berberine. The oil is unlikely to be used for medicinal purposes due to its toxic effects.
- Gupta, R.S., Dixit, V.P. & Dobhal, M.P., 1990. Antifertility studies of isoquinoline alkaloids with special emphasis on structure activity relationship. Fitoterapia 61(1): 67-71.
- Morton, J.F., 1981. Atlas of medicinal plants of Middle America. Bahamas to Yucatan. Charles C. Thomas, Springfield, Illinois, United States. pp. 241-242.
- Quisumbing, E., 1978. Medicinal plants of the Philippines. Katha Publishing Co., Quezon City, the Philippines. pp. 329-332.
- Sharma, V. & Nathawat, G.S., 1987. Allelopathic effect of Argemone mexicana L. on species of Triticum, Brassica, Raphanus and Pennisetum. Current Science (India) 56(9): 427-428.
- Upreti, K.K., Das, M. & Khanna, S.K., 1991. Biochemical toxicology of argemone oil. 1. Effect on hepatic cytochrome P-450 and xenobiotic metabolizing enzymes. Journal of Applied Toxicology 11(3): 203-209.
- van Steenis, C.G.G.J., 1954. Argemone. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana. Series 1, Vol. 5. Wolters-Noordhoff Publishing, Groningen, the Netherlands. pp. 114-116.
Other selected sources
- Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. Revised reprint. 2 volumes. Ministry of Agriculture and Co-operatives, Kuala Lumpur, Malaysia. Vol. 1 (A-H) pp. 1-1240, Vol. 2 (I-Z) pp. 1241-2444.
- Council of Scientific and Industrial Research, 1948-1976. The wealth of India: a dictionary of Indian raw materials & industrial products. 11 volumes. Publications and Information Directorate, New Delhi, India.232, 261, 441, 527, 739, 786, 788, 935, 987, 1010, 1047.
Tran Cong Khanh