Cestrum nocturnum (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Cestrum nocturnum L.

Protologue: Sp. pl. 1: 191 (1753).

Family: Solanaceae

Chromosome number: 2n= 16

• Night blooming cestrum, night blooming jessamine (En)
• Philippines: dama de noche (Sp, Tagalog)
• Thailand: raatree
• Vietnam: dạ lý hương.

C. nocturnum probably originates from Central America, and is widely cultivated and locally naturalized throughout the tropics. It is cultivated throughout South-East Asia.

C. nocturnum has been introduced in South-East Asia as an ornamental for its sweet-scented flowers, which bloom at night. In Central America and the Caribbean a leaf decoction is used as a lotion on skin eruptions. In former times a fruit extract was taken orally as a sedative in cases of epilepsy, chorea and hysteria, the treatment being gradually reduced and terminated within a short time. In Thailand the leaves are considered toxic to humans, but they may be used in small doses to treat epilepsy. The leaves are used in Chinese folk medicine as an external application for burns and swellings.

All parts of C. nocturnum are rich in saponins, yielding some 4-5%. The leaves yield flavonol glycosides and numerous steroidal saponins (e.g. nocturnoside A, tigogenin, smilagenin and yuccagenin). Some of these saponins show considerable cytotoxic activity against human squamous cell carcinoma (HSC-2) cells with LD₅₀values ranging from 2.0 μg/ml to 13 μg/ml, sometimes being 5-10 times more active than against normal human gingival fibroblasts. The saponin fraction showed cardiovascular effects and may act as a respiratory stimulant. Older reports mention cardiotonic and cardiotoxic properties for a saponin isolated from C. nocturnum .

Fresh powdered leaves of C. nocturnum show promising control against the beetles Sitophilus oryzae (rice weevil) and Trogoderma granarium , two common pests in stored grain. Phenylacetylaldehyde, one of three principal volatile compounds emitted from the flowers, strongly attracts the females of the cabbage looper moth ( Trichoplusia ni ).

Toxicity reports of C. nocturnum in livestock in southern Africa mention dullness, tachycardia, rising temperature, suppression of urine and decrease in respiratory rate as symptoms. Death occurs with coma and slight convulsions. Toxicity of Cestrum for livestock involves several systems. One system mimics vitamin D attributes and influences calcium uptake, leading to a condition called calcinosis. An example of this system is found in C. diurnum L., originating from the Caribbean and occasionally cultivated in South-East Asia. Another system involves liver poisoning and explains the frequent records of hepatotoxic compounds in C. laevigatum Schlechtendal and C. parqui L’Hérit.

A methanol-water (1:1) extract of C. parqui aerial parts showed inhibition of carrageenininduced oedema in rats. The aggregation of human blood platelets induced by adenosine diphosphate and platelet activating factor was also inhibited with an IC₅₀of 3 mg/ml and 2 mg/ml, respectively. The extract did not however inhibit arachidonic acidmediated platelet aggregation.

An evergreen shrub up to 4 m tall; branches erect or drooping, angular, olive or bluish-green, lenticellate, glabrescent. Leaves alternate, simple and entire, narrowly ovate to ovate, (4-)8-13 cm × (1.5)2-4.5(-6) cm, base obtuse or narrowly cuneate, apex acute, membranous to coriaceous; petiole 1-2 cm long; stipules absent. Inflorescence an axillary or terminal cyme 3-8 cm long, often combined in a large leafy panicle. Flowers bisexual, regular, fragrant, yellow or greenish-white, pedicellate; bracteoles 2, one leafy, the other linear; calyx cupular, 2-4.5 mm long, 5-6-toothed; corolla tube 20-30 mm long, gradually expanding upward, 5-lobed, lobes 2-5 mm long; stamens included, filaments adnate to the corolla tube, upper part free, with 2 teeth at base of free part; ovary superior, 2-celled, style exserted. Fruit a globose berry 0.5-1 cm in diameter, whitish, 1-3-seeded. Seeds ovoid, 2.5-6 mm long, black.

C. nocturnum can be found flowering and fruiting throughout the year, intermittently profusely flowering.

Cestrum consists of some 150 species, and is indigenous from the southern United States to Chile. Numerous species are cultivated throughout the world for their ornamental value, in South-East Asia e.g. C. laevigatum , C. nocturnum and C. parqui .

In South-East Asia C. nocturnum is cultivated and locally naturalized from sea-level up to 1600 m altitude.

Management C. nocturnum can be easily propagated by semi-hardwood cuttings.

C. nocturnum is cultivated throughout the tropics and does not appear to be threatened by genetic erosion.

Recently, steroidal saponins as found in C. nocturnum have received scientific attention because of their structural diversity and significant biological activity. The application of powdered leaves to control insect pests in stored grain deserves more attention.

80, 138, 306, 626, 646, 844.

15, 62, 330, 760.

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Slamet Sutanti Budi Rahayu