Oldenlandia (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Oldenlandia L.

Protologue: Sp. pl. 1: 119; Gen. pl. ed. 5: 55 (1754).

Family: Rubiaceae

Chromosome number: x= 9; O. affinis: 2n= 18, O. brachypoda: 2n= 32, 54, O. corymbosa: 2n= 18, 36, 54, O. herbacea: 2n= 18, 36

Major species

• Oldenlandia brachypoda DC.,
• O. capitellata (Wallich ex G. Don) O. Kuntze,
• O. corymbosa L.

Origin and geographic distribution

Oldenlandia consists of approximately 100 species (but estimates of up to 300 species have also been made), and is distributed in all tropical and subtropical regions.

Uses

In many areas whole Oldenlandia plants are used internally in a decoction to treat fever, stomach disorders and diarrhoea. Externally they are commonly used pounded in poultices to treat ulcers, wounds, bruises, snake bites, insect stings, broken bones, rheumatism, lumbago and ague. In traditional medicine in India, O. corymbosa is used in the treatment of jaundice and gonorrhoea. The aerial parts of O. brachypoda and O. corymbosa are used in Chinese medicine to treat tumours in liver, lungs and rectum, and as an antiphlogistic.

In India, the bark of the roots of O. umbellata L. was much used to prepare a red dye before the large-scale production of synthetic dyes started at the end of the 19th Century. A decoction of its leaves and bark is considered expectorant and is prescribed in cases of bronchial catarrh, bronchitis and asthma, and is also used as a wash for poisonous bites.

Production and international trade

Oldenlandia is usually collected in the wild, and because it often acts as a weed, it is usually available in sufficient amounts for private use. There is no real international trade, although small amounts of dried plants are exported from China.

Properties

Tests with O. brachypoda showed inhibition on aflatoxin B1-induced mutagenesis using Salmonella typhimurium TA 100 as the bacterial tester strain and rat liver supernatant as the activation system. This suggests that it possesses mutagenic activity and possibly cancer chemopreventive properties. In tests with mice in Indonesia, O. corymbosa leaves caused humoral immune response stimulation and suppression on the phagocytosis system. The water-soluble fraction administered intraperitonially had no influence on cellular immune responses, but the residue fraction given orally caused stimulation. O. brachypoda markedly stimulated murine spleen cells to proliferate in in vitro studies. This suggests that it has immunomodulatory activity.

Nine iridoid glucosides have been isolated from the aerial parts of O. corymbosa, among which asperuloside, asperulosidic acid and scandoside methyl ester. Some iridoids are known to have antiphlogistic activity.

Description

• Annual herbs or sometimes herbaceous perennials; stem erect or procumbent.
• Leaves opposite, simple and entire, sessile or petiolate; stipules interpetiolar and adnate to leaf-bases.
• Inflorescence terminal or axillary, cymose and paniculate or corymbose, sometimes flowers in fascicles or solitary.
• Flowers bisexual, protandrous, small, 4-merous, homostylous or heterostylous; calyx with turbinate, globose or oblong tube, and distinct lobes; corolla hypocrateriform or narrowly infundibular, with valvate lobes, white, pale mauve, blue or pink; stamens with filaments attached at the corolla tube between the lobes, anthers dorsifixed; ovary inferior, 2-locular, with 2-many ovules, style terete or filiform, stigma usually bifid but sometimes capitate.
• Fruit a crustaceous capsule, loculicidally dehiscent at apex, usually many-seeded.
• Seeds obconical, meniscoid, scutelliform, cerebriform or obovoid, with variously patterned surface.
• Seedling with epigeal germination; cotyledons very small, ovate.

Growth and development

Most Oldenlandia species are annual and complete their lifespan from seed to seed in a short period, which is in accordance with their status as weed. Some species are perennial, e.g. O. capitellata.

Other botanical information

Oldenlandia is often included in Hedyotis. However, recent studies in northern America, Australia and India have shown that there are differences in habit and morphology of inflorescences, flowers, fruits and seeds, as well as in cytology, embryology and palynology, so Oldenlandia has been kept separate here.

Several Oldenlandia species are difficult to distinguish and often confused. The correct name for the taxon usually referred to as O. diffusa is O. brachypoda DC., although some caution is needed as the "true" O. diffusa (Willd.) Roxb. is also a widespread weed.

Ecology

Oldenlandia often occurs in disturbed locations such as grasslands and roadsides. Several species are common weeds in fields; O. corymbosa is particularly common in e.g. cassava, pineapple and maize throughout the tropics.

Propagation and planting

In O. corymbosa three plant types have been determined: a type in which almost all seeds are non-dormant and germinate immediately in light at 35-40°C, a type in which almost all seeds are dormant and need a pre-germination treatment at 12°C for 7 days, and a type in which approximately 50% of the seeds are dormant and the remainder are non-dormant.

Tests with the Indian species O. umbellata showed promising results for in vitro propagation. Direct somatic embryogenesis and subsequent plant formation were achieved by using leaves, pieces of stems, axillary buds and developing fruits. The best results were obtained in half-strength Murashige and Skoog basal medium containing only 12% of the usual N content, supplemented with 0.2 mg/l benzyladenine, 0.1% ascorbic acid and 1.5% sucrose under diffuse light (300 lux). Rooting was achieved in the same medium, but with naphthalene-acetic acid instead of benzyladenine.

Harvesting

For personal use, whole plants of Oldenlandia are usually harvested in small amounts, when needed.

Handling after harvest

Freshly harvested Oldenlandia plants are often used immediately, but sometimes they are dried and stored for later use or trade.

Genetic resources and breeding

In South-East Asia the medicinally used Oldenlandia species are common weeds and widely distributed, so there is no danger of genetic erosion.

Prospects

Several tests on the mutagenic activity and possible cancer chemopreventive properties of Oldenlandia have given positive results; animal tests on immune response stimulation and suppression on the phagocytosis system have also been promising. The antiphlogistic properties attributed to Oldenlandia are interesting. More research is needed to establish the definite medicinal value of these plants.

Taxonomic research on Oldenlandia and related genera on a worldwide basis is desirable. Species and genus concepts and delimitations differ greatly, resulting in much confusion in floras of the various regions.

Literature

• Corbineau, F. & Côme, D., 1981. Some particularities of the germination of Oldenlandia corymbosa L. seeds (tropical Rubiaceae). Israel Journal of Botany 29: 157-167.
• Halford, D.A., 1992. Review of the genus Oldenlandia L. (Rubiaceae) and related genera in Australia. Austrobaileya 3(4): 683-722.
• Huang, J.-T., 1981. Neue Iridoide aus Oldenlandia diffusa Roxb. [New iridoids from Oldenlandia diffusa Roxb.]. Archiv der Pharmazie 314(10): 831-836.
• Otsuka, H., Yoshimura, K., Yamasaki, K. & Cantoria, M.C., 1991. Isolation of 10-O-acyl iridoid glucosides from a Philippine medicinal plant, Oldenlandia corymbosa L. (Rubiaceae). Chemical and Pharmaceutical Bulletin 39(8): 2049-2052.
• Quisumbing, E., 1978. Medicinal plants of the Philippines. Katha Publishing Co., Quezon City, the Philippines. pp. 920-922.
• Rao, G.P. & Bahadur, B., 1990. Somatic embryogenesis and plant regeneration in self incompatible Oldenlandia umbellata L. (Rubiaceae). Phytomorphology 40(1-2): 95-101.
• Sivarajan, V.V. & Biju, S.D., 1990. Taxonomic and nomenclatural notes on the Hedyotis corymbosa-diffusa complex (Rubiaceae) in India. Taxon 39(4): 665-674.
• Sutarjadi, Santosa, M.H., Bendryman & Dyatmiko, W., 1991. Immunomodulatory activity of Piper betle, Zingiber aromatica, Andrographis paniculata, Allium sativum, and Oldenlandia corymbosa grown in Indonesia. Planta Medica 57, Supplement Issue 2: A136.
• Wong, B.Y.Y., Lau, B.H.S., Tadi, P.P. & Teel, R.W., 1992. Chinese medicinal herbs modulate mutagenesis, DNA binding and metabolism of aflatoxin B1. Mutation Research 279(3): 209-216.
• Wong, B.Y.Y., Lau, B.H.S., Yamasaki, T. & Teel, R.W., 1993. Modulation of cytochrome P-450IA1-mediated mutagenicity DNA binding and metabolism of benzo-a-pyrene by Chinese medicinal herbs. Cancer Letters 68(1): 75-82.

Selection of species

• Oldenlandia affinis
• Oldenlandia biflora
• Oldenlandia brachypoda
• Oldenlandia capitellata
• Oldenlandia corymbosa
• Oldenlandia herbacea

Authors

• N.O. Aguilar & R.H.M.J. Lemmens