Pogostemon auricularius (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Pogostemon auricularius (L.) Hassk.

Protologue: Tijdschr. natuurl. gesch. physiol. 10: 127 (1843).

Family: Labiatae

Chromosome number: 2n= 34

Pogostemon auricularius (L.) Hassk. - 1, flowering stem; 2, flower; 3, pistil; 4, frontal and dorsal view of nutlet

Synonyms

• Dysophylla auricularia (L.) Blume (1826).

Vernacular names

• Indonesia: ke kucing (Aceh), ketumpang (Javanese), kambing kambing (Kalimantan)
• Malaysia: kekucing
• Philippines: buntot pusa (Tagalog)
• Thailand: saapraeng saapkaa (peninsular)
• Vietnam: tú hùng hình tai, cỏ cò.

Origin and geographic distribution

P. auricularius is distributed from India throughout South-East Asia and southern China but is not recorded from the Lesser Sunda Islands and from Australia.

Uses

In Peninsular Malaysia and Indo-China, P. auricularius is commonly used in the treatment of simple stomach problems in children. The pounded leaves, sometimes mixed with lime, are applied as a poultice on the abdomen. In Indonesia, a poultice made from the leaves is also applied as a cure for diarrhoea, colic, worms, sores, kidney problems, and a sore throat. The leaves are chewed in Java against colic and flatulence. In Indo-China, a decoction is drunk to cure malaria, whereas a lotion is applied as a rubefacient against rheumatism. In Thailand, roots, stems or leaves are used as a diuretic or antipyretic. P. auricularius has also been mentioned as a potential anti-carcinogen.

The ground leaves of P. glaber Benth. are externally applied to relieve pain and itching of mosquito bites. In Malesia, an infusion of leaves of several Pogostemon species, e.g. P. auricularius, P. cablin, P. heyneanus Benth. and P. verticillatus (Roxb.) Bhatti & Ingr., is taken to allay painful menstruation. The leaves are also added to bath water to alleviate rheumatism. P. heyneanus is also known to be used as a carminative and diuretic, and as an insecticide for stored cereals. From the leaves of P. cablin (Blanco) Benth. an important essential oil, patchouli oil, is produced. The leaves are also put between clothes as an insect repellent, and the volatile oil is also used as an insect and leech repellent.

Production and international trade

In Malesia, dried plants of P. auricularius are sold in Chinese pharmacies.

Properties

From the aerial parts of P. auricularius, 4 cleistanthane type diterpenoids (C₂₀) were isolated, of which one was identified as auricularic acid. On preliminary screening, these compounds exhibit spasmolytic activity.

The volatile oil of P. cablin contains a number of sesquiterpenes, of which (-)-patchouli alcohol (patchoulol), and the closely related derivatives patchoulenol and patchoulenone are most abundant. Patchouli alcohol, pogostol and pogostone (dwelwanine) show antimicrobial activity against periodontopathic bacteria and/or fungi, while patchouli alcohol also showed significant inhibitory activity on K⁺ induced contractures of a guinea-pig taenia coli preparation. Patchouli alcohol, pogostol, stigmast-4-en-3-one, retusin and pachypodol show anti-emetic activity on copper sulphate induced-emesis in young chickens. The aerial parts also contain the flavonoid licochalcone A, which is used in the treatment of promyelocytic leukaemia cells (HL-60) with licochalcone A induced cell differentiation. Some Pogostemon species show toxicity to Anopheles stephensi and Culex quinquefasciatus mosquito larvae.

Description

• An erect or procumbent, strong smelling annual herb, 30-80 cm tall, stem simple or laxly branched, weak, bluntly 4-angular, pubescent with spreading hairs, pinkish.
• Leaves decussate, elliptical to ovate, 4-6 cm × 2-3 cm, base cuneate, apex acute, margin irregularly serrate, except near the base, membranaceous, pubescent and glandular on both surfaces; petiole 2-10 mm long, hairy; stipules absent.
• Inflorescence composed of crowded verticillasters, forming a dense terminal spike, 4-8 cm long; bracts narrowly elliptical, long ciliate.
• Calyx subcampanulate, gland-dotted outside, 1.2-1.5 mm long, 5-toothed, teeth subequal, triangular, ciliate; calyx in fruit urn-shaped, 2.5-3.5 mm long, teeth often incurved over the nutlets; corolla 2-3.5 mm long, tube slender, exserted, lobes 4, equal, obtuse, pubescent, lavender, pale pink or white; stamens 4, subequal, filaments 3.5-4 mm long, slender, upper half villous, lilac; style 5 mm long, bifid; disk 0.3 mm long.
• Fruit consisting of 4 dry 1-seeded schizocarpous nutlets enclosed in the persistent calyx, nutlets ellipsoid, 0.6 mm × 0.4 mm, finely reticulate, brown.
• Seedling with epigeal germination; hypocotyl 1-2 mm long, glandular; cotyledons triangular, 2 mm long, apex obtuse; epicotyl hairy, greenish to purplish; first leaves 2, ovate, 3.5 mm long, margin crenate, nerves prominent, hairy, glandular underneath.

Growth and development

P. auricularius flowers and fruits throughout the year. In marshy locations the stems are prostrate and root at the nodes. Plants spread over 1-2 m, with the erect flowering branches arising from the main stem. Pogostemon is pollinated by insects.

Other botanical information

Pogostemon, including the genus Dysophylla, comprises almost 80 species, which are distributed from India to China and Japan, and throughout South and South-East Asia. India is the centre of diversity. The species that belonged to Dysophylla are still recognized at the sub-generic level, and P. auricularius, the former type of Dysophylla, now belongs to subgenus Dysophyllus, section Dysophyllus.

Ecology

P. auricularius grows on sunny, constantly or periodically humid localities, borders of ditches, dams and upland rice fields, grassy wasteland and thickets. It is locally often common, from the lowland to 2000 m altitude.

Propagation and planting

P. auricularius is propagated by seed, which is hydro- and epizoochorous.

Diseases and pests

Specific information on P. auricularius is not available, but Pogostemon species are often affected by fungi including Alternaria and Cercospora spp., which attack the leaves, while other fungi attack the roots of the perennial species. In India, several viruses are known to cause mottling of the leaves of Pogostemon as well. Nematodes such as Heterodera marioni in Indonesia and Helicotylenchus, Tylenchorhynchus and Meloidogyne incognita in India, are very common pests.

Harvesting

P. auricularius is harvested from the wild whenever the need arises.

Handling after harvest

The leaves or whole plants of P. auricularius are dried in the shade, or used fresh.

Genetic resources and breeding

P. auricularius is widespread in anthropogenic habitats and does not seem to be at risk of genetic erosion. No breeding programmes or germplasm collections are known to exist.

Prospects

The isolated compounds from P. auricularius need more research to assess their usefulness. Until more is known, its use will remain of local importance only.

Literature

• Bhatti, G.R. & Ingrouille, M., 1997. Systematics of Pogostemon (Labiatae). Bulletin of the Natural History Museum. Botany series 27(2): 77-147.
• Hussaini, F.A., Agarwal, S., Roy, R., Prakash, O. & Shoeb, A., 1988. Novel cleistanthane diterpenoids from Pogostemon auricularius. Journal of Natural Products 51(2): 212-216.
• Ingrouille, M. & Bhatti, G.R., 1998. Infragenetic relationships within Pogostemon Desf. (Labiatae). Botanical Journal of the Linnean Society 128(2): 159-183.
• Keng, H., 1978. Labiatae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana. Series 1, Vol. 8. Sijthoff & Noordhoff International Publishers, Alphen aan den Rijn, the Netherlands. pp. 301-394.
• Oyen, L.P.A., 1999. In: Oyen, L.P.A. & Nguyen Xuan Dung (Editors): Plant Resources of South-East Asia No 19. Essential-oil plants. Backhuys Publishers, Leiden, the Netherlands. pp. 151-157.
• Soerjani, M., Kostermans, A.J.G.H. & Tjitrosoepomo, G. (Editors), 1987. Weeds of rice in Indonesia. Balai Pustaka, Jakarta, Indonesia. pp. 610-611.

Other selected sources

• [135] 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.
• [510] Kardinan, A., Wikardi, E.A., Sidik, M., Rejesus, B.M., Garcia, R.P., Champ, B.R., Bengston, M., Dharmaputra, O.S. & Halid, H., 1997. The prospects of botanical pesticides on stored food insects management. BIOTROP Special Publication 59: 199—208.
• [764] Osawa, K., Matsumoto, T., Maruyama, T., Takiguchi, T., Akuda, K. & Takazoe, I., 1990. Studies of the antibacterial activity of plant extracts and their constituents against peridontopathic bacteria. Bulletin of Tokyo Dental College 31(1): 17—21.
• [774] Park, E.J., Park, H.R., Lee, J.S. & Kim, J., 1998. Licochalcone A: an inducer of cell differentiation and cytotoxic agent from Pogostemon cablin. Planta Medica 64(5): 464—466.
• [802] Prakash, O., Roy, R., Agarwal, S., Hussaini, F.A. & Shoeb, A., 1987. Stereostructure of auricularic acid, a cleistanthane diterpenoid from Pogostemon auricularius Hassk. Tetrahedron Letters 28(6): 685—686.
• [1102] Yang, Y., Kinoshita, K., Koyama, K., Takahashi, K., Tai, T., Nunoura, Y. & Watanabe, K., 1999. Anti-emetic principles of Pogostemon cablin (Blanco) Benth. Phytomedicine 6(2): 89—93.

Authors

• Eulis Retnowati