Peperomia pellucida (PROSEA)
Peperomia pellucida (L.) Kunth
- Protologue: Humb., Bonpl. & Kunth, Nov. gen. sp. 1: 64 (1816).
- Family: Piperaceae
- Chromosome number: 2n= 44
- Piper pellucidum L. (1753),
- Piper exiguum Blume (1826).
- Indonesia: ketumpangan air (Malay, Sumatra), sasaladaan (Sundanese), suruh-suruhan (Javanese)
- Malaysia: ketumpangan air (Malay, Peninsular)
- Philippines: ulasiman-bato (Tagalog), olasiman-ihalas (Cebu Bisaya), tangon-tangon (Bikol)
- Thailand: chaa kruut (peninsular), phak krasang (central), phak haak kluai (northern)
- Vietnam: rau càng cua.
Origin and geographic distribution
Peperomia comprises over 1000 species. Its main centre of distribution is in Central and South America. In South-East Asia, 50-90 species occur. P. pellucida is native to South America but has naturalized widely in the Old World tropics. It is common in South-East Asia, occurring throughout the region.
In the Philippines, the whole plant of P. pellucida is used as a warm poultice to treat abscesses, boils and pimples. An infusion or decoction is used against gout, kidney troubles and rheumatic pain, and externally as a rinse for complexion problems. In Peninsular Malaysia, the plant is boiled and the water drunk to relieve rheumatism and fatigue. In Java, the juice of the leaves is prescribed for colic and abdominal pains, and the bruised leaves are applied to the temples to treat headache. The plant is eaten as a salad. In West Africa, it is similarly eaten as a vegetable, and used in local medicine to treat convulsions. In Central and South America, it is widely used in local medicine in similar applications as described for the Philippines. It is recommended to eat P. pellucida as a culinary herb because it has an aromatic taste and stimulates appetite and digestion.
P. pellucida contains an essential oil with apiole (a phenylpropane derivative) as the main component. Further components are the related 2,4,5-trimethoxystyrene, caryophyllene (a sesquiterpenoid), and an (unidentified) sesquiterpene alcohol. Apiole affects the kidney parenchyma; there are reports in the literature of kidney and liver damage due to apiole. The known strong diuretic activity is also probably toxic. In pure form the compound stimulates the uterus, provoking menstruation; its misuse as an abortifacient which can lead to serious intoxifications is also known.
The essential oil from the whole plant showed fungicidal activity at a minimum inhibitory concentration of 2000 ppm, with a wide range of toxicity and quick killing activity. It was thermostable, remained toxic for at least 150 days, was non-phytotoxic and non-systemic. The oil is antagonistic to the growth of Helminthosporium oryzae (brown spot) in rice.
An ethyl acetate extract of the air-dried plants showed antibacterial activity against Bacillus subtilis , Pseudomonas aeruginosa and Staphylococcus aureus . The antibacterial activity was more potent than the penicillin standard used. The water extract of leaves showed antimutagenic activity.
Several flavonoids have been isolated from the plant, including acacetin, apigenin, pellucidatin, pellucidatin-8-neohesperidoside and isovitexin.
Adulterations and substitutes
Apiole, the main constituent of the essential oil, is better known from the root of parsley (Petroselinum crispum (Miller) Nyman ex A.W. Hill).
- A small fleshy herb, up to 30 cm tall; stems initially erect, becoming decumbent, rooting at nodes, glabrous, internodes up to 5 cm long and 2 mm in diameter.
- Leaves spirally arranged, simple, ovate elliptical to broadly ovate or almost triangular, 2.5-3.5 cm × 2-3 cm, entire, membranous when dry, 5-veined, base rounded to truncate, apex acute; petiole up to 20 mm long and about 1 mm in diameter, glabrous; stipules absent.
- Inflorescence a terminal or axillary spike, solitary, glabrous, peduncle 0.5-1.5 cm long and about 0.5 mm in diameter, fertile axis 2-5 cm long and about 0.5 mm in diameter.
- Flowers bisexual, sessile, not sunken into axis, spaced 0.4-1 mm apart; floral bracts rounded, 0.3-0.4 mm × 0.2-0.3 mm; perianth absent; stamens 2, anthers oblong, about 0.1 mm × 0.1 mm; ovary superior, rounded-oblong, about 0.3 mm × 0.3 mm, 1-locular.
- Fruit drupe-like, subglobose, 0.5-1 mm in diameter, sticky, papillate, 1-seeded.
Growth and development
P. pellucida is presumed to be an annual but its lifespan is unknown. The profusely produced seed is probably dispersed by rain wash and more widely by people as a contaminant in soil. Plant growth is fast under moist conditions.
Other botanical information
Some botanists separate Peperomia from the Piperaceae into the Peperomiaceae, on the basis of the absence of stipules, the presence of two stamens and on differences in pollen morphology and anatomy.
Although there is a recent revision for Australia (and Africa), no overall revision of Peperomia is available for South-East Asia. It is very difficult to compare the names and species for the Philippines, New Guinea, Peninsular Malaysia and Java from the literature, and no botanical information is available for other Malesian regions. P. tetraphylla (J.G. Forster) Hook. & Arn. is another pantropical representative that occurs in South-East Asia. Although it is used in local medicine in South America, there are no reports of its medicinal use in South-East Asia.
P. pellucida is mostly found in disturbed habitats up to 1000 m altitude. It is a common and widespread weed, frequent in gardens and cultivated areas that are damp and lightly shaded, particularly common on damp hard surfaces such as walls, roofs, steep gullies, and in flower pots. Under certain growing conditions impoverished types that were previously described as separate species can develop.
Propagation and planting
P. pellucida produces seed in abundance. It is not cultivated in South-East Asia. In West Africa, however, it is cultivated from seed and reputed for its fast growth.
P. pellucida is collected fresh whenever the need arises.
Genetic resources and breeding
Since P. pellucida is a common pantropical weed the risk of genetic erosion is minimal.
P. pellucida is easy to grow, even in urban settings, and is a nutrituous and savoury vegetable. Its fungicidal properties deserve further research for low-budget applications. The significant antibacterial activity of the ethyl acetate extract suggests a potential as a broad-spectrum antibiotic.
- de Padua, L.S. & Pancho, J.V., 1983. Handbook on Philippine medicinal plants. Vol. 4. University of the Philippines, Los Baños, the Philippines. p. 45.
- Düll, R., 1973. Die Peperomia-Arten Afrikas [The Peperomia species of Africa]. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 93: 56-129.
- Forster, P.I., 1993. A taxonomic revision of the genus Peperomia Ruiz & Pav. (Piperaceae) in mainland Australia. Austrobaileya 4(1): 93-104.
- Jose, J., Thoppil, J.E. & Mathew, L., 1992. Chromosome complement studies in five species of Peperomia Ruiz and Pav. Cytologia 57(2): 227-229.
- Morton, J.S., 1981. Atlas of medicinal plants of middle America. Bahamas to Yucatan. Charles C. Thomas Publisher, Springfield, Illinois, United States. pp. 120-121.
- Nguyen Van Duong, 1993. Medicinal plants of Vietnam, Cambodia and Laos. Mekong Printing, Santa Ana, California, United States. p. 331.
- Poscidio, G.N., Garcia, E.A. & Bojo, A.C., 1993. Antibacterial activity of Peperomia pellucida (L.) HBK, family Piperaceae. Philippine Journal of Biotechnology 4(2): 199.
- Quisumbing, E., 1978. Medicinal plants of the Philippines. Katha publishing Co., Quezon City, the Philippines. pp. 210-211.
- Singh, A.K., Dikshit, A. & Dixit, S.N., 1983. Antifungal studies of Peperomia pellucida. Beitrage zur Biologie der Pflanzen 58(3): 357-368.
- van der Zon, A.P.H. & Grubben, G.J.H., 1976. Les légumes-feuilles spontanés et cultivés du Sud-Dahomey [Wild and cultivated leaf vegetables of South Dahomey]. Communications 65. Koninklijk Instituut voor de Tropen, Amsterdam, the Netherlands. p. 84.
Other selected sources
97, 202, 572, 580, 1227, 1570, 1647, 1648.