Crescentia (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Crescentia L.

Protologue: Sp. pl. 2: 626 (1753); Gen. pl. ed. 5: 274 (1754).

Family: Bignoniaceae

Chromosome number: x= 20; C. cujete: 2n= 40

• Crescentia alata Kunth,
• C. cujete L.

Crescentia comprises 6 species ranging from Mexico and the West Indies to Amazonian Brazil; two species have been introduced in South-East Asia.

Originating from Central America and the West Indies, the medicinal uses of Crescentia in South-East Asia are rather limited. The medicinal uses pertain to their astringent and diuretic properties, and are similar to the uses in the neotropics. In the West Indies, the fruit pulp of C. cujete is used for skin diseases in dogs. The hollowed shell of C. cujete fruits is used throughout its distribution area as a household utensil. The smaller fruit of C. alata is less often used for rattles, ladles and cups.

Crescentia is only used on a local scale.

Phytochemical investigations of the fruits of C. cujete afforded 16 iridoids and iridoid glucosides. Eight of them were new, and named crescentins I-V and crescentosides A, B and C. Another 8 compounds were already known, and subsequently identified as ajugol, 6-O-p-hydroxybenzoylajugol, aucubin, 6-O-p-hydroxybenzoyl-6-epiaucubin, agnuside, ningpogenin, 5,7-bisdeoxycyanchoside and a degradation product of glutinoside. Further investigations afforded another 8 compounds: acanthoside D (a lignan), β-D-glucopyransoyl benzoate, (R)-1-O-β-D-glucopyranosyl-1,3-octanediol, β-D-fructofuranosyl 6-O-(p-hydroxybenzoyl)-α-D-glucopyranoside, three glycosides of (2R,4S)-2,4-pentanediol, two glycosides of (R)-4-hydroxy-2-pentanone, two glycosides of (R)-1,3-octanediol and 6-O-(p-hydroxybenzoyl)-D-glucose.

From the 2-butanone extract of wood chips of C. cujete the following compounds were isolated: (2S,3S)-3-hydroxy-5,6-dimethoxydehydroiso-α-lapachone, (2R)-5,6-dimethoxydehydroiso-α-lapachone, and (2R)-5-methoxydehydroiso-α-lapachone (all naphthoquinones), as well as 2-(1-hydroxyethyl)naphtho(2,3-b)furan-4,9-dione, 5-hydroxy-2-(1-hydroxyethyl)naphtho(2,3-b)furan-4,9-dione, 2-isopropenylnaphtho(2,3-b)furan-4,9-dione, and 5-hydroxydehydroiso-α-lapachone. All compounds exhibited selective activity against DNA-repair-deficient yeast mutants. The first three naphthoquinones exhibited cytotoxic activity against Vero cells, with IC₅₀ values of 3.7-4.7μg/ml.

The methanolic extract of the root bark of C. cujete was active against gram positive bacteria but not significantly against gram negative bacteria. Additional fractionation of a chloroform extract led to the isolation of vanillic acid, with minimum inhibitory concentrations (MIC) of 125 and 175μg/ml against Staphylococcus aureus and Bacillus subtilis, respectively, and 4-hydroxybenzoic acid with an MIC of 250μg/ml against both organisms.

Phytochemical and biological studies on C. alata are very limited. The methanol extract showed strong antibacterial activity against Sarcina lutea and weak activity against Staphylococcus aureus and Proteus vulgaris. Two flavonoids, chysanthemin and cyanidin-3-O-β-D-rutinosides, were isolated from the flowers of C. alata.

• Small to medium-sized trees, crown open.
• Leaves simple or 3-foliolate, borne on thick twigs in alternate fascicles; petiolate; stipules absent.
• Inflorescence consisting of 1-2 flowers, cauliflorous, arising from nodes on the trunk and older branches.
• Flowers bisexual, whitish; calyx large, usually bilabiately split; corolla tubular to campanulate with a fold midway across the lower side of the throat, behind which is a nectar-storing bulge, lobes deltoid, acuminate; stamens 4, didynamous, slightly exserted, anther cells divergent; ovary superior, ovoid-elliptical, 1-locular, ovules multi-seriate on 4 parietal placentas.
• Fruit a large berry, more or less spherical, indehiscent with a hard woody shell, pulpy inside.
• Seed not winged, embedded in the pulp.
• Seedling with epigeal germination; hypocotyl elongated; cotyledons leafy.

C. cujete has a relatively short trunk and long spreading branches. The trunk develops as older branches are lost. The long spreading branches become pendulous distantly by their own weight. The renewal shoot arises from the upper surface in the initial curve of the pendulous branch. The part distal to the renewal shoot becomes a branch of the tree, the part proximal to the renewal shoot becomes part of the trunk. Its architecture represents Champagnat’s model. The flowers are nocturnal, they expand in the evening and the next morning the corolla falls off, unfaded. They are pollinated by bats attracted by the musky odour. The fleshy fruits are mammal dispersed in their native range. Crescentia can be found flowering and fruiting throughout the year.

Species of Crescentia are defined entirely by vegetative characters and differences in fruit size. All species are interfertile. Nevertheless species tend to form dense aggregations of homogenous morphotypes where they occur, and taxonomic recognition of different-appearing ecological dominants seems valid.

The two Crescentia species treated here show a preference for relatively open savanna areas, and are common in coastal savannas in Central America and the West Indies. Their natural range and ecological preferences are partly blurred by the long history of cultivation.

Crescentia can easily be propagated by seed or cuttings. In South-East Asia, Crescentia is usually propagated by cuttings. In a germination trial in southern Africa seed of C. cujete showed a high germination rate within 3 weeks after scarification and boiling-water treatments. High germination may also be achieved without any treatment. Seedlings required about 3 months to achieve the recommended height of 20 cm for field-planting of nursery stock. Plants should be grown in full sun in a moisture-retentive, loam-based soil mix with additional organic matter.

Leaves and bark of Crescentia are collected whenever the need arises, whereas fruits are collected when mature.

Leaves of Crescentia are used fresh, whereas bark or fruit are used either fresh or dried.

Both Crescentia species treated here have a large area of distribution, either naturally or as a result of cultivation, and do not seem to be at risk of genetic erosion. The genetic basis in South-East Asia may be limited as most plants are propagated by cuttings.

A vast array of compounds is present in C. cujete of which some, i.e. the substituted naphthoquinones, display interesting pharmacological activities in the field of antimutagenesis and cytotoxicity. More research is needed, however, to fully evaluate their potential as possible lead compounds in future medicinal investigations.

• Binutu, O.A., 1997. Phytochemical and antimicrobial studies on Crescentia cujete. Fitoterapia 68(2): 184-185.
• Gentry, A.H., 1980. Bignoniaceae - Part I (Crescentieae and Tourrettieae). In: Organization for Flora Neotropica (Editor): Flora Neotropica Monograph 25(1). 130 pp.
• Heltzel, C.E., Gunatilaka, A.A.L., Glass, T.E., Kingston, D.G.I., Hoffmann, G. & Johnson, R.K., 1993. Bioactive furanonaphthoquinones from Crescentia cujete. Journal of Natural Products 56(9): 1500-1505.
• Kaneko, T., Ohtani, K., Kasai, R., Yamasaki, K. & Nguyen Minh Duc, 1997. Iridoids and iridoid glucosides from fruits of Crescentia cujete. Phytochemistry 46(5): 907-910.
• Kaneko, T., Ohtani, K., Kasai, R., Yamasaki, K. & Nguyen Minh Duc, 1998. N-Alkyl glycosides and p-hydroxybenzoyloxy glucose from fruits of Crescentia cujete. Phytochemistry 47(2): 259-263.
• Sukrasno, 1986. Phytochemical contents of "bernuk" (Crescentia cujete L.) Bignoniaceae bark. Magister Thesis. Department of Pharmacy, Faculty of Mathematics and Natural Sciences, Institut Technology Bandung, Indonesia. 84 pp.

• Sri Hayati Widodo