Toona sinensis

Toona sinensis
Foliage and seed capsules
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Sapindales
Family:	Meliaceae
Genus:	Toona
Species:	T. sinensis
Binomial name
Toona sinensis (A.Juss.) M.Roem.

Toona sinensis (syn. Cedrela sinensis A.Juss.; Chinese Mahogany, Chinese Toon, or Red Toon (Chinese: 香椿; pinyin: xiāngchūn; Hindi: daaraluu; Malay: suren; Vietnamese: tông dù) is a species of Toona native to eastern and southeastern Asia, from North Korea south through most of eastern, central and southwestern China to Nepal, northeastern India, Myanmar, Thailand, Malaysia, and western Indonesia.^{[1][2][3][4][5]}

Leaf (unusual specimen with terminal leaflet)

It is a deciduous tree growing to 25 m tall with a trunk up to 70 cm diameter. The bark is brown, smooth on young trees, becoming scaly to shaggy on old trees. The leaves are pinnate, 50–70 cm long and 30–40 cm broad, with 10–40 leaflets, the terminal leaflet usually absent (imparipinnate) but sometimes present; the individual leaflets 9–15 cm long and 2.5–4 cm broad, with an entire or weakly serrated margin. The flowers are produced in summer in panicles 30–50 cm long at the end of a branch; each flower is small, 4–5 mm diameter, with five white or pale pink petals. The fruit is a capsule 2–3.5 cm long, containing several winged seeds.^[1][4][5][6]

Medicinal Uses

The fruit, bark, and roots are used in traditional Chinese medicine.Toona sinensis can induce apoptosis of cancer cells, reduce plasma glucose in diabetic rats, and improve lipolysis of differentiated 3T3-L1 adipocyte and its uptake of glucose.^[7] It has also been shown that TS may increase dynamic activity of human sperm.^[8]

Toona can safely prevent and alleviate lung cancer proliferation in vitro and in vivo.It has the potential to be developed as an anti-lung cancer drug.^[9],^[10] Leaf extracts of Toona sinensis have cytotoxic activity on several cancer cells including prostate cancer cells. Gallic acid has been identified as the major anti-cancer compound. It is cytotoxic to DU145 prostate cancer cells.^[11] Intraperitoneal injection of Toona extract suppressed the proliferation of ovarian cancer cells without toxicity.^[12]

Leaf extract of Toona sinensis can inhibit SARS-CoVcoronavirus in vitro.^[13]

Toona extract may improve learning and memory.^[14]

Cultivation and uses

The young leaves of T. sinensis (xiāngchūn) are extensively used as a vegetable in China; they have an onion-like flavour. Plants with red young leaves are considered of better flavour than those where the young leaves are green.^[1][15][16]

The timber is hard and reddish; it is valuable, used for furniture making.^[1][6]

Outside of its native region T. sinensis is valued more as a large ornamental tree for its haggard aspect.^[5][17] It is by far the most cold-tolerant species in the Meliaceae and the only member of the family that can be cultivated successfully in northern Europe.

Culture

In Chinese literature, Toona sinensis is often used for a rather extreme metaphor, with a mature tree representing a father. This manifests itself occasionally when expressing best wishes to a friend's father and mother in a letter, where one can write "wishing your Toona sinensis and daylily are strong and happy" (simplified Chinese: 椿萱并茂; traditional Chinese: 椿萱並茂; pinyin: chūnxuānbìngmào), with Toona sinensis metaphorically referring to the father and daylily to the mother.

References

1. ^ ^{a b c d} Flora of China (draft): Meliaceae
2. ^ Germplasm Resources Information Network: Toona sinensis
3. ^ University of Melbourne: Sorting Toona names
4. ^ ^{a b} Hong Kong trees: Toona sinensis (in Chinese, with photos; google translation)
5. ^ ^{a b c} Rushforth, K. (1999). Trees of Britain and Europe. Collins ISBN 0-00-220013-9.
6. ^ ^{a b} Taiwan Forestry: Toona sinensis (in Chinese, with photos; google translation)
7. ^ Yang Y.-C., Hsu H.-K., Hwang J.-H., Hong S.-J. "Enhancement of glucose uptake in 3T3-L1 adipocytes by Toona sinensis leaf extract" Kaohsiung Journal of Medical Sciences 2003 19:7 (327-333)
8. ^ Ling Poon S., Leu S.-F., Hsu H.-K., Liu M.-Y., Huang B.-M. "Regulatory mechanism of Toona sinensis on mouse leydig cell steroidogenesis" Life Sciences 2005 76:13 (1473-1487)
9. ^ Yang C.-J., Huang Y.-J., Wang C.-Y., Wang C.-S., Wang P.-H., Hung J.-Y., Wang T.-H., Hsu H.-K., Huang H.-W., Kumar S.P.A., Huang M.-S., Weng C.-F."Antiproliferative and antitumorigenic activity of toona sinensis leaf extracts in lung adenocarcinoma." Journal of Medicinal Food 2010 13:1 (54-61)
10. ^ Yang C.-J., Huang Y.-J., Wang C.-Y., Wang P.-H., Hsu H.-K., Tsai M.-J., Chen Y.-C., Bharath Kumar V., Huang M.-S., Weng C.-F. "Antiproliferative effect of Toona sinensis leaf extract on non-small-cell lung cancer" Translational Research 2010 155:6 (305-314
11. ^ Chen H.-M., Wu Y.-C., Chia Y.-C., Chang F.-R., Hsu H.-K., Hsieh Y.-C., Chen C.-C., Yuan S.-S. "Gallic acid, a major component of Toona sinensis leaf extracts, contains a ROS-mediated anti-cancer activity in human prostate cancer cells." Cancer Letters 2009 286:2 (161-171)
12. ^ "The fractionated Toona sinensis leaf extract induces apoptosis of human ovarian cancer cells and inhibits tumor growth in a murine xenograft model Gynecologic Oncology 2006 102:2 (309-314)
13. ^ Chen C.-J., Michaelis M., Hsu H.-K., Tsai C.-C., Yang K.D., Wu Y.-C., Cinatl Jr. J., Doerr H.W. "Toona sinensis Roem tender leaf extract inhibits SARS coronavirus replication" Journal of Ethnopharmacology 2008 120:1 (108-111)
14. ^ Liao J.-W., Hsu C.-K., Wang M.-F., Hsu W.-M., Chan Y.-C."Beneficial effect of Toona sinensis Roemor on improving cognitive performance and brain degeneration in senescence-accelerated mice British Journal of Nutrition 2006 96:2 (400-407)
15. ^ Plants for a Future: Toona sinensis
16. ^ Oriental Vegetable Seeds: Toona sinensis
17. ^ More, D. & White, J. (2003). Cassell's Trees of Britain & Northern Europe. London:Weidenfeld & Nicolson. p. 709