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19: Essential-oil plants

Litsea cubeba (Lour.) Persoon

Syn. pl. 2: 4 (1807).

LAURACEAE

2n = 24

Laurus cubeba Lour. (1790), Litsea citrata Blume (1826), Tetranthera polyantha Wallich ex Nees var. citrata Meissner (1864).

May chang (originally Chinese), pheasant pepper tree (En). Indonesia: krangean (Javanese), lado-lado (Sumatra), baleng la (East Kalimantan). Malaysia: medang ayer, medang melukut. Thailand: chakhai-ton (northern), takhrai (south-western), takhrai-ton (north-eastern). Vietnam: c[aa]y m[af]ng tang.

Litsea cubeba occurs wild from the eastern Himalayas to continental South-East Asia, Malaysia, Indonesia (Java, Kalimantan, Sumatra), southern China (up to the Yangtze river) and Taiwan. It is cultivated for its essential oil mainly in Japan, China and Taiwan. In Java it is grown on a small scale.

Essential oils are steam-distilled from the fruits and from the leaves of Litsea cubeba. The essential oil obtained from the fruits is called 'may chang' oil. It is a commercial source of citral which is used for the production of ionones and formerly vitamin A and in essences for cosmetics, foodstuffs and tobacco products. Because of its pleasant citrus-like smell and taste it is a modifier for lemon and lime flavours and a general freshener in fruit flavours. In perfumery may chang oil is used as an alternative for verbena oil and lemongrass oil in colognes, household sprays, soaps and air-fresheners.
In Java, 2 slightly different essential oils are steam-distilled from the leaves. The oil produced in West Java is called trawas oil, that from Central Java krangean oil. Both oils are used medicinally and in soap perfumes.
In Indonesia, the fruits are eaten as a vegetable side dish and are a common substitute for the spice Piper cubeba L.f., while in northern Vietnam tea is sometimes flavoured with the flowers.
All plant parts of Litsea cubeba are applied medicinally and have antiparalytic, anticephalalgic, antihysteric, carminative, spasmolytic and diuretic properties. The fruit is used in decoction for the treatment of vertigo, paralysis and in post-partum preparations; the leaves for treating skin diseases. Traditionally the Dayak Kenyah people of East Kalimantan use the fruits and bark as oral and topical medicine for babies as well as for adults. It is applied in cases of fever, stomach-ache, chest pain and as a tonic. It is also an antidote to treat drunkenness. In aromatherapy the oil is applied as a cooling agent against acne and dermatitis, and to relieve anxiety and stress. Recent studies found that the essential oil may be useful in the treatment of cardiac arrhythmia. Litsea cubeba oil has in vitro antifungal properties against several pathogens such as Alternaria alternata, Aspergillus niger, Candida albicans, Fusarium spp., Helminthosporium spp.
In China Litsea cubeba is planted as a wind-break in tea plantations and the wood has some value as timber. In Nepal the leaves serve as a source of fodder, while in Assam (India) muga silkworms (Antheraea assama) are sometimes reared on the leaves.

China is the major producer of may chang oil, with an annual production of about 2000 t, of which more than 50% is exported. Litsea cubeba oils fetch a price per kg of US$ 4 (1994), thus competing strongly with lemongrass oil. Trawas oil and krangean oil are produced on a small scale only and are not traded internationally.

All parts of Litsea cubeba contain essential oil, but only may chang oil steam disilled from the fruit is of major commercial importance. The essential oil content of the fruit ranges from 0.3—5.0% (dry weight). May chang oil is pale yellow with a fresh lemon-like and sweet-fruity smell and a soft, sweet-fruity dry-out. It is almost free of the fatty-grassy notes of lemongrass oil, but lacks the tenacity of the latter. In perfumery it blends well with many other natural and synthetic aroma materials. The main chemical component is citral, which is a mixture of the stereoisomers geranial and neral. Other components are limonene, methyl-heptenone, 'ALFA'-pinene and linalool. The oil has been approved for food use by the Food and Drug Administration of the United States in paragraph 182.20. See also: Composition of essential-oil samples and the Table on standard physical properties.
The leaves of Litsea cubeba contain up to 7% essential oil (dry weight). The chemical composition of the oil is variable. Krangean oil from Central Java contains mainly 1,8-cineole (about 50%), and smaller amounts of citral (10%), citronellal (1%), linalool, 'ALFA'-pinene and 'BETA'-pinene; in trawas oil, from West Java, the main components are 1,8-cineole and citronellal (both 25%). Analysis of a leaf oil from China indicated 1,8-cineole (50%) and sabinene (17%) as the main components, while linalool (78%) was the primary component of a leaf oil from India. Analysis of a flower oil in China indicated sabinene as the main component (62%). A sample of bark oil from India contained citronellol (41%), linalool (22%) and citronellal (18%). Several alkaloids have also been isolated from various parts of Litsea cubeba. Among those recently isolated and identified are laurotetanine, O-methyloblongine, oblongine, xanthoplanine and magnocararineu. Bioassay studies have indicated termicidal, antiasthmatic and antianaphylactic activities. The seed contains a fatty oil, from which lauric acid and capric acid are produced.

Because of its lower market price, may chang oil is often used as a substitute for lemongrass oil, but synthetic citral is even cheaper. May chang oil is sometimes adulterated with synthetic citral.

Small, dioecious, deciduous tree or shrub, 5—10(—15) m tall; trunk terete, up to 6(—20) cm in diameter; bark 1 mm thick, very tough, green outside, yellow inside, smooth, with large lenticels, lemon-like scent and pungent taste; branchlets slender, glabrous but apical parts ferrugineous-villose. Leaves alternate, simple, aromatic; petiole 8—18 mm long; blade lanceolate to oblong, 7—15 cm x 1.5—3 cm, base acute, apex long-acuminate, membranaceous or chartaceous, finely pellucid-dotted, brownish-green when young, shiny dark-green above, glaucous below, lateral veins slender, in 8—12 pairs. Inflorescence an axillary, 4—5-flowered, umbelliform raceme, about 1 cm long; primary peduncle accrescent, up to 1 cm long; secondary peduncle thin, 5—8 mm long, with basal, lanceolate bract and apically a globose involucre of 4 decussate bracts surrounding the umbel like a flower bud; pedicel minutely puberulous, 3—4 mm long; flower 3—4 mm in diameter, yellowish-white; tepals 5—6, broadly ovate, 1.5—2.5 mm long, outside glabrous; male flowers with 9 stamens in 3 whorls, filaments sparsely hairy, those of 3rd whorl with 2 basal subsessile glands, anthers quadrangular; female flowers with 9 staminodes, a large, glabrous ovary with very short style and a large, multi-lobed stigma. Fruit a globose berry, 5—6 mm across, apiculate when young, blackish when mature, seated on a pedicel 3—5 mm long which is slightly thickened at the apex into a cup-shaped receptacle. Seed spherical, white.

Litsea cubeba flowers on both long and short shoots, with flowering on the short shoots dominating. Under strongly seasonal conditions, flowering occurs before the unfolding of the leaves, with male trees blooming earlier than the female ones. In natural stands, female plants may outnumber male ones by 5:3 to 5:4. In Indonesia flowering and fruiting is throughout the year, in Taiwan, however, flowering is from February—May, fruiting in September—October. Clonal trees of Litsea cubeba bear fruit after 2—3 years.

Several other Litsea species produce essential oils, e.g. Litsea elliptica Blume (synonym: Litsea odorifera Valeton) and Litsea glutinosa (Lour.) C.B. Robinson. Litsea elliptica leaf oil contains besides safrole (used as a substitute of sassafras) the ketones and alcohols 12-tridecen-2-one, 10-undecen-2-one and undecen-2-ol. The oil (and sawdust) can also be used as an insect repellent. The fruit of Litsea glutinosa contains about 0.3% essential oil with (E)-'BETA'-ocimene (70—84%) as the main constituent.
Litsea diversifolia Blume (vernacular names: huru kisereh (Sundanese), nangka-an (Javanese)) is a small tree (3—12 m tall, trunk up to 25 cm in diameter but usually much smaller) of mixed mountain forest in Java (1000—2500 m altitude). The wood is occasionally used in house building but it is said to have a pleasant cinnamon smell and a decoction of shredded wood is drunk like tea.

Litsea cubeba is found in hilly areas and grows well at altitudes of 700—2300 m; in East Kalimantan it occurs at 400—600 m. In Java it is found on fertile loams and also near sulphur lakes.

Litsea cubeba is propagated by wildlings or nursery-grown seedlings. Seed loses its viability rapidly. After collection, the fruit flesh is removed and cleaned seeds are sown in containers. Shade is not necessary, but protection against heavy rain is required, to prevent the seeds from being washed out. Germination starts 6—8 weeks after sowing and continues for about 5 months. The first seedlings are ready for transplanting after 9 months; slower ones take up to 20 months. Although Litsea cubeba is grown on a fairly large scale in China, Japan and Taiwan, and as a smallholder crop in Java, very little is known about its husbandry. Litsea cubeba is affected by the papillionid Chilasa slateri which feeds on the leaves. It can be controlled by spraying insecticides (e.g. dichlorvos). Fruits are harvested when the citral content is highest, i.e. just before it turns red and becomes fully ripe. Fruits are often dried at room temperature for 1—2 weeks, traditionally in bamboo containers. The essential oil is extracted by steam distillation. About 100 kg fruit may yield up to 1—5 kg essential oil.

No germplasm collections or breeding programmes of Litsea cubeba are known to exist.

Litsea cubeba is a promising essential-oil crop, mainly as a cheap source of citral for industrial use, but also as a medicinal plant used in aromatherapy. To reach its potential, however, selection of the best chemotypes and research on the husbandry of the crop are urgently required.

Bao Yipei, 1995. Progress and status of research on Chinese Litsea cubeba oil. Chemistry and Industry of Forest Products 15(2): 71—77.
Coppen, J.J.W., 1995. Flavours and fragrances of plant origin. Non-wood Forest Products No 1. Food and Agriculture Organization of the United Nations, Rome, Italy. pp. 61—64.
Gogoi, P., Baruah P. & Nath, S.C., 1997. Antifungal activity of the essential oil of L. cubeba Pers. Journal of Essential Oil Research 9: 213—215.
Khanh, H.C., 1988. Evaluation and status of the essential oils production in the provinces of central Vietnam. Proceedings of the Seminar on Technology of Essential Oils, Hanoi, Vietnam, December, 6—9, 1988. pp. 53—60.
Lawrence, B.M., 1996. Progress in essential oils: Litsea cubeba. Perfumer and Flavorist 21(5): 62.
Lee, S.S., Lin, Y.J., Chen, C.K., Liu, K.C. & Chen, C.H., 1993. Quaternary alkaloids from Litsea cubeba and Cryptocarya konishii. Journal of Natural Products 56: 1971—1976.
Li, Hui-Lin et al., 1976. Flora of Taiwan. Vol. 2. Epoch Publishing Company, Taipei, Taiwan. pp. 434—448.
Lin, T.S. & Yin, H.W., 1995. Effects of Litsea cubeba press oils on the control of termite Coptotermes formosanus Shiraki. Bulletin of the Taiwan Forestry Research Institute 10(1): 59—63.
Nath, S.C., Hazarika, A.K., Baruah, A. & Sharma, K.K., 1996. Essential oils of Litsea cubeba Pers. — An additional chemotype of potential industrial value from northern India. Journal of Essential Oil Research 8: 575—576.
Susiarti, S., 1995. Peran baleng la (Litsea cubeba) sebagai tumbuhan obat dan aroma pada masyarakat Dayak Kenyah di Pujungan, Kalimantan Timur [The role of baleng la (Litsea cubeba) as a medicinal and aromatic plant in the Dayak Kenyah community at Pujungan, East Kalimantan]. Paper presented at the Symposium Nasional I Tumbuhan Obat Dan Aromatik (Apinmap Simposium), Bogor, Indonesia, 10—12 October 1995.

M.A. Nor Azah & S. Susiarti

Nor Azah, M.A. & Susiarti, S., 1999. Litsea cubeba (Lour.) Persoon. In: L.P.A. Oyen and Nguyen Xuan Dung (Editors): Plant Resources of South-East Asia No 19: Essential-oil plants. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea