459

12(1): Medicinal and poisonous plants 1

Styphnolobium japonicum (L.) Schott

Wiener Zeitschr. Kunst. 3: 844 (1830).

LEGUMINOSAE

2n = 28

Sophora japonica L. (1767).

Japanese pagoda tree, Chinese scholar tree, umbrella tree (En). Indonesia: sari cina, sari kuning. Vietnam: c[aa]y h[of]e.

Styphnolobium japonicum is native to central and northern China and Korea, but now widely cultivated in temperate and subtropical regions of the world, in South-East Asia at least in Vietnam and Thailand.

The flower buds of Styphnolobium japonicum are astringent and possess styptic properties. They are a reputed remedy for the prevention of various types of haemorrhages (e.g. haemoptysis, epistaxis, metrorrhagia), haemorrhoids, and are useful for the treatment of hypertension. Flower buds and young pods are an important source of rutin, which has 'vitamin P'-like properties and is used in the treatment of conditions characterized by increased capillary permeability and fragility. An extract from the pods is toxic. Styphnolobium japonicum is also reputed to show oestrogenic activity.
The flower buds and occasionally also the pods are used for dyeing yellow or granite-grey. The dye was mainly used to dye silk. Mixed with indigo, it gives a green colour. Styphnolobium japonicum is commonly cultivated as an ornamental. Its tough and durable wood is used for door and window frames and agricultural implements. The shoots seem to be a suitable fodder, but as the pods are poisonous they should be given with care. In China, an extract of the leaves and pods is used to adulterate opium. A gum similar to that from carob (Ceratonia siliqua L.) can be extracted from the seeds.

The seeds and pods of Styphnolobium japonicum contain various haemagglutinins (lectins). This probably explains the toxic effect of intravenous administration of a seed or pod extract. The lectin fraction, called Styphnolobium japonicum agglutinin (SJA) can furthermore be separated into two more subfractions; a D-galactose/N-acetyl-D-galactosamine specific lectin (B-SJA-I) and a D-mannose/D-glucose specific lectin (B-SJA-II). In agglutination experiments, Styphnolobium japonicum agglutinin (SJA) demonstrated blood group specificity for the B-group human erythrocytes. Binding experiments with frozen sections of human kidneys also showed specific binding to the endothelia in specimens from blood groups B or AB, thus indicating a D-galactose/N-acetyl-D-galactosamine receptor specificity. Furthermore, the Styphnolobium japonicum agglutinin appears to be devoid of mitogenic and immuno-suppressive activity, in contrast to, for example, concanavalin A, which suppresses the T helper-dependent antibody response to sheep erythrocytes. The flavonoid-glycoside rutin (also known as rutoside, quercetin-3-rutinoside or 3,3',4',5,7-pentahydroxyflavone-3-rutinoside) is found in high concentrations in the flower buds. Known as a 'capillary protectant', the substance is used to treat capillary and venous disorders. Alone, or in combination with other drugs it is a common ingredient of vascular protective agents and venous tonics, and of topical agents in phlebology. Evidence of its value, however, still remains somewhat inconclusive.
Using an activity-guided procedure, an anti-haemostatic principle in the flower buds has been identified as the flavonoid isorhamnetin-(2-(3-methoxy-4-hydroxyphenyl)-3,5,7-trihydroxy-4H-1-benzopyran-4-one).
HPLC analysis of commercially available samples of Styphnolobium japonicum in Taiwan revealed the presence of the flavonoids rutin, quercetin, sophoricoside, sophorabioside and genistein. Flower buds contained a great deal of rutin, while the immature fruits contained sophoricoside and sophorabioside. When flower buds were stir-fried for short periods over low heat, the extracted rate of rutin and quercetin increased slightly, decreasing with longer cooking periods at higher temperatures. When stir-fried with vinegar, flower buds quickly blackened, but when cooked with honey, they changed very little. Immature fruits, however, exhibit less variation in their active constituents after processing. All processed samples of Styphnolobium japonicum have a pronounced aroma and could be more easily extracted with water than the unprocessed samples.
In a detailed study in Egypt on flavonoid contents of the various plant parts no qualitative changes were observed in the different development stages of leaves or flowers. The number and diversity of flavonoids gradually increase during transformation from flower to fruit. Sophorabioside, sophora-flavanoloside and genistein glucoside appeared at the beginning of fruit formation, while sophoricoside appeared only at maturity. The total rutin concentration was highest in flower buds (24%). The rutin content in leaves decreases from young to mature leaves.
An intragastrically administered aqueous extract of the flower buds showed strong anti-ulcer activity against ulcerations in rats induced by ethanol HCl. The mutagenic potential of a crude, freeze-dried hot-water extract was evaluated using the Ames test, and the micronucleus and chromosomal aberration assays in mice in vivo. Styphnolobium japonicum (+/- S9) was found to significantly induce His⁺-revertants in Salmonella typhimurium TA 98 and/or TA 100 strains. The extract was furthermore found positive in both in vivo assays.
Leaves contain 18.2% crude protein based on dry weight. The wet fractionation process was applied to twigs, leaves and pods. The leaf-protein concentrate obtained from the green juice after pressing contained 16% crude protein, which is very low and 69% total lipids, which is very high; both values were determined on a dry matter basis. Seeds contain 9.9% fatty oil which is rich in linoleic acid (52.8%), but is poor in drying properties. The seed-cake contains 30% protein, but glycosides should be removed before using it as fodder.

Other sources for industrial extraction of rutin are the leaves of Fagopyrum esculentum Moench, a cereal especially from temperate zones, and the leaves of some Eucalyptus species e.g. Eucalyptus macrorhyncha F. v. Mueller ex Benth. from Australia.

A deciduous, small to medium-sized tree up to 25(-30) m tall; bole generally short; bark surface corrugated, dark greenish-brown or dark grey-green, with paler lenticels; crown broad. Leaves arranged spirally, imparipinnate, 15-25 cm long; stipules early caducous; leaflets alternate to subopposite, 7-17, elliptical to ovate-lanceolate, 1.5-6 cm x 1-2.5 cm, acute or sometimes obtuse at apex, mucronate, glabrous or sparsely hairy above, short-haired below, shortly petiolulate; stipellae absent or small and setaceous. Flowers in a terminal, 15-35 cm long panicle, papilionaceous; bracteoles present; calyx 3-4 mm long, teeth shorter than the tube; corolla yellowish-white or greenish-white, standard 12-15 mm long; stamens 10, filaments joined near the base; ovary superior, pilose. Fruit an indehiscent pod, 3-12 cm x 7-12 mm, constricted between the seeds, stipitate, glabrous, beaked, 1-8-seeded. Seeds 8 mm x 4-5 mm, yellowish-brown. Seedling with epigeal germination; cotyledons emergent; first few leaves imparipinnate or sometimes 1- or 3-foliolate.

Seeds of Styphnolobium japonicum germinate quickly, usually within about 4 days. The tree starts flowering when about 3-4 years old, though sometimes only when about 30 years old. In Vietnam, trees flower from May to August and fruit from September to November. In China, flowering is in August-September, fruiting in October-November.

Styphnolobium is a small genus of 9 species occurring in North and Central America, with Styphnolobium japonicum as the only Asian representative. The segregation of Styphnolobium from the closely related genus Sophora is supported by morphological characters (flowers with bracteoles, pods indehiscent), a different somatic chromosome number and the results of DNA studies. The DNA studies even indicate that the two genera are not closely related. Several varieties have been distinguished within Styphnolobium japonicum, the status of which is still unclear, and several cultivars are grown as ornamentals.

Styphnolobium japonicum is well adapted to dry weather conditions and to a great variety of soils, but thrives best in well-drained, sandy loam. Being native in temperate and subtropical regions, cultivation in the tropics is only possible in drier regions or at higher altitudes. Under temperate conditions Styphnolobium japonicum is tolerant of heat and drought, whereas it also tolerates severe frost (up to -25°C) except when young.

Styphnolobium japonicum can be propagated by seed, which should be scarified or treated with hot water and soaked before sowing. Under temperate conditions the seed germinates well and within a few days. Grafting, layering, greenwood and root cuttings are used for ornamental cultivars. Trees can be coppiced successfully.

Among the reported diseases and pests of Styphnolobium japonicum are fungi such as Uromyces truncicola which cause a canker disease in seedlings, and leafminers such as Odontota dorsalis, and aphids (Aphis spp.).

Flower buds, inflorescences and young fruits of Styphnolobium japonicum are hand picked. Inflorescences are harvested when flowers begin to open. Young stems can simply be cut as routine under coppice management.

Analyses of bark, leaves, flower buds, flowers and fruits of Styphnolobium japonicum revealed that the highest rutin content (24-37%) was found in young flower buds and the lowest (1.5-3%) in the bark. In view of the total volume and weight of harvestable plant parts it is recommended to use the flower buds, flowers and young fruits as a source of rutin. In the temperate zones Styphnolobium japonicum is considered fast-growing.

After harvesting, the inflorescences of Styphnolobium japonicum are dried, and rachises and pedicels discarded. Rutin is extracted by subsequent boiling in water and crystallization upon cooling, followed by recrystallization from ethanol.

Various ornamental cultivars of Styphnolobium japonicum are available, mainly in western Europe, e.g. weeping, dwarf and variegated forms. Breeding efforts should be directed towards plants flowering at a relatively early age.

Styphnolobium japonicum is an important industrial source of rutin. Research in further applications in the treatment of capillary and venous disorders deserves more attention.

Balbaa, S.I., Zaki, A.Y. & El-Shamy, A.M., 1974. Qualitative and quantitative study of the flavonoid content of different organs of Sophora japonica at different stages of development. Planta Medica 25: 325-330.
Doan Thi Nhu, Nguyen Thuong Thuc, Do Huy Bich & Vu Thuy Huyen (Editors), 1991. Les plantes médicinales au Vietnam (livre 1) [The medicinal plants of Vietnam (volume 1)]. Médicine traditionelle et pharmacopée. Agence de coopération Culturelle et Technique, Paris, France. p. 76.
González, G., Alzuetta, C., Barro, C. & Salvador, A., 1988. Yield and composition of protein concentrate, press cake, green juice and solubles concentrate from wet fractionation of Sophora japonica L. foliage. Animal Feed Science and Technology 20: 177-188.
Ishida, H., Umino, T., Tsuji, K. & Kosuge, T., 1989. Studies on the antihemostatic substances in herbs classified as hemostatics in traditional Chinese medicine. I. On the antihemostatic principles in Sophora japonica L. Chemical and Pharmaceutical Bulletin 37(6): 1616-1618.
Palomino, G., Martínez, P., Bernal, C. & Sousa, S.M., 1993. Differencias cromosomicas entre algunas especies de los generos Sophora L. y Styphnolobium Schott [Chromosomal differences between some species of the genera Sophora L. and Styphnolobium Schott]. Annals of the Missouri Botanic Garden 80: 284-290.
Perry, L.M., 1980. Medicinal plants of East and Southeast Asia. Attributed properties and uses. The MIT Press, Cambridge, Massachusetts, United States & London, United Kingdom. pp. 226-227.
Poretz, R.D. & Barth, R.F., 1976. Studies on the interaction of the Sophora japonica lectin and concanavalin A with erythrocytes and lymphocytes. Immunology 31(2): 187-194.
Sangat-Roemantyo, H. & Wirdateti, 1991. Sophora japonica L. In: Lemmens, R.H.M.J. & Wulijarni-Soetjipto, N. (Editors): Plant Resources of South-East Asia No 3. Dye and tannin-producing plants. Pudoc, Wageningen, the Netherlands. pp. 113-115.
Sousa, S.M. & Rudd, V.E., 1993. Revision del genero Styphnolobium (Leguminosae: Papilionoideae: Sophoreae) [Revision of the genus Styphnolobium (Leguminosae: Papilionoideae: Sophoreae)]. Annals of the Missouri Botanic Garden 80: 270-283.
Ueno, M., Ogawa, H., Matsumoto, I. & Seno, N., 1991. A novel mannose-specific and sugar aggregatable lectin from the bark of the Japanese pagoda tree (Sophora japonica). Journal of Biological Chemistry 266: 3146-3153.

[193] Bruneton, J., 1995. Pharmacognosy, phytochemistry, medicinal plants. Technique & Documentation Lavoisier, Paris, France. 915 pp.
[202] 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.
[287] Council of Scientific and Industrial Research, 1948-1976. The wealth of India: a dictionary of Indian raw materials & industrial products. 11 volumes. Publications and Information Directorate, New Delhi, India.
[360] Djordjevic, S. & Gorunovic, M., 1991. Etude de Sophora japonica L. comme source d'obtention du rutoside [A study of Sophora japonica L. as a source of rutoside]. Herba Hungarica 30(1-2): 11-15.
[710] Kass, E. & Wink, M., 1997. Phylogenetic relationships in the Papilionoideae (family Leguminosae) based on nucleotide sequences of cpDNA (rbcL) and ncDNA (ITS 1 and 2). Molecular Phylogenetics and Evolution 8(1): 65-88.
[806] Laitinen, L., Juusela, H. & Virtanen, I., 1990. Binding of the blood group-reactive lectins to human adult kidney specimens. Anatomical Record 226(1): 10-17.
[871] Liu, I.M. & Sheu, S.J., 1989. Analysis and processing of Chinese herbal drugs. VIII: The study of sophorae floe. American Journal of Chinese Medicine 17(3-4): 179-187.
[997] Muto, Y., Ichikawa, H., Kitagawa, O., Kumagai, K., Watanabe, M., Ogawa, E., Seiki, M., Shirataki, Y., Yokoe, I. & Komatsu, M., 1994. Studies on antiulcer agents. I. The effects of various methanol and aqueous extracts of crude drugs on antiulcer activity. Yakugaku Zasshi 114(2): 980-994. (in Japanese)
[1035] Nguyen Van Duong, 1993. Medicinal plants of Vietnam, Cambodia and Laos. Mekong Printing, Santa Ana, California, United States. 528 pp.
[1036] Nguyen Van Thuan, Dy Phon, P. & Niyomdhan, C., 1987. Légumineuses-Papilionoïdées [Leguminosae-Papilionoideae]. In: Lescot, M. (Editor): Flore du Cambodge, du Laos et du Viênam [Flora of Cambodia, Laos and Vietnam]. Vol. 23. Muséum National d'Histoire Naturelle, Paris, France. 258 pp.
[1045] Niyomdham, C., 1980. Preliminary revision of tribe Sophoreae (Leguminosae-Faboideae) in Thailand: Ormosia Jacks. and Sophora Linn. Thai Forest Bulletin, Botany 13: 1-22.
[1128] Pételot, A., 1952-1954. Les plantes médicinales du Cambodge, du Laos et du Vietnam [The medicinal plants of Cambodia, Laos and Vietnam]. 4 volumes. Centre National de Recherches Scientifiques et Techniques, Saigon, Vietnam.
[1277] Samuelsson, G. (Editor), 1992. Drugs of natural origin, a textbook of pharmacognosy. Swedish Pharmaceutical Press, Stockholm, Sweden. 320 pp.
[1283] Santamour, F.S. & Riedel, L.G.H., 1997. A new name for Sophora japonica. Journal of Arboriculture 23(4): 166-167.
[1468] Townsend, C.C., 1974. Leguminales. In: Townsend, C.C. & Guest, E. (Editors): Flora of Iraq 3. The Ministry of Agriculture and Agrarian Reform, Baghdad, Iraq. 662 pp.
[1480] Tsoong, P.-C. & Ma, C.-Y., 1981. A study on the genus Sophora Linn. Acta Phytotaxonomica Sinica 19: 1-22, 143-167.
[1554] Watt, J.M. & Breyer-Brandwijk, M.G., 1962. The medicinal and poisonous plants of southern and eastern Africa - being an account of their medicinal and other uses, chemical composition, pharmacological effects and toxicology in man and animal. Livingstone, Edinburgh, United Kingdom. 1457 pp.
[1634] Yin, X.J., Liu, D.X., Wang, H.C. & Zhou, Y., 1991. A study on the mutagenicity of 102 raw pharmaceuticals used in Chinese traditional medicine. Mutation Research 260(1): 73-82.

Tran Cong Khanh

Tran Cong Khanh, 1999. Styphnolobium japonicum (L.) Schott. In: de Padua, L.S., Bunyapraphatsara, N. and Lemmens, R.H.M.J. (Editors): Plant Resources of South-East Asia No 12(1): Medicinal and poisonous plants 1. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea