Botanical Name: Aesculus turbinata
Species: A. turbinata
*Aesculus turbinata f. pubescens (Rehder) Ohwi ex Yas Endo
*Aesculus turbinata var. pubescens Rehder
*Aesculus dissimilis Blume
*Pawia dissimilis Kuntze
*Pawia turbinata Kuntze
Common Names: Japanese horse-chestnut
Habitat: Aesculus turbinata is native to Japan but cultivated elsewhere. It grows on mountains, especially in ravines, all over Japan. In deciduous forests, especially in moist slopes along streams.
Aesculus turbinata is a deciduous Tree growing to 20 m (65ft) by 12 m (39ft) at a medium rate.
It is not frost tender. It is in flower in June, and the seeds ripen in September. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees.
The bark is dark brown and the surface is peeled off and waved. The leaves are palmate compound leaves. Stems, flowers and leaves are big. In early summer, it produces an upright inflorescence from the branch tip and blooms a flower mixed with small male flowers and bisexual flowers. At the base of the white four-petaled flower there is a crimson mottle. Seven long male persimmons stick out of the flower. The flowers are the source of honey, the fruits are similar to chestnuts, and the starch is often used as a material for mulberry or dumpling.
Landscape Uses:Specimen. Prefers a deep loamy well-drained soil but is not too fussy. The dormant plant is very cold-hardy, though the young growth in spring can be damaged by late frosts. It prefers growing in a continental climate, doing best in eastern and south-eastern England. Most members of this genus transplant easily, even when fairly large. Special Features:Attractive foliage, Not North American native, Blooms are very showy.
Young leaves cooked. Some caution is advised on this entry since the leaves are likely to contain toxic saponins (see notes above on toxicity). Seed – cooked. It can be dried, ground into a flour and used as a gruel. The starch is extracted and eaten. The seed is quite large, about 25 – 30mm in diameter, and is easily harvested. Unfortunately it is also rich in saponins and these need to be removed before the seed can be eaten. See also the notes below on toxicity. The following notes apply to A. californica, but are probably also relevant here:- The seed needs to be leached of toxins before it becomes safe to eat – the Indians would do this by slow-roasting the nuts (which would have rendered the saponins harmless) and then cutting them into thin slices, putting them into a cloth bag and rinsing them in a stream for 2 – 5 days. Most of the minerals etc would also have been leached out by this treatment.
Natural seeds of Japanese horse chestnut (Aesculus turbinata Blume) contain large amounts of mixed triterpenoidal saponins called escins. Recent studies have shown that escins have several biological activities including anti-inflammatory action and inhibitory effects on the absorption of ethanol and glucose. For the edible utilization of the seeds, natural seeds are usually treated with wooden ashes to remove harshness. Here, we found the novel compounds derived from escins in the edible seeds after the food processing with wooden ashes. The instrumental analyses revealed the chemical structures of escins and the derivatives. These compounds are identified as four types of deacetylescins Ia, IIa, Ib, and IIb as well as two types of desacylescins I and II. To determine their biological activity, the purified compounds were tested for their potential nutraceutical activity. The oral glucose tolerance test in mice revealed that a single oral administration of the isolated components of deacetylescins at a dose of 100 mg/kg was clearly effective in attenuating the elevation of blood glucose levels. The inhibitory effects of escins and their derivatives were in the order of escins>deacetylescins>desacylescins. Moreover, we found the inhibitory activity of those compounds on pancreatic lipase. Escins were the most potent in inhibiting the enzyme activity, and followed by desacylescins and then deacetylescins. Taken together, our results suggest the potential usefulness of novel saponins including deacetylescins and desacylescins from edible seeds as novel sources for nutraceutical foods with anti-obese effects.
Saponins in the seed are a soap substitute. The saponins can be easily obtained by chopping the seed into small pieces and infusing them in hot water. This water can then be used for washing the body, clothes etc. Its main drawback is a lingering odour of horse chestnuts. Wood – weak, nicely grained. Used for house fittings, domestic items etc.
The seed is rich in saponins. Although poisonous, saponins are poorly absorbed by the human body and so most pass through without harm. Saponins are quite bitter and can be found in many common foods such as some beans. They can be removed by carefully leaching the seed or flour in running water. Thorough cooking, and perhaps changing the cooking water once, will also normally remove most of them. However, it is not advisable to eat large quantities of food that contain saponins. Saponins are much more toxic to some creatures, such as fish, and hunting tribes have traditionally put large quantities of them in streams, lakes etc in order to stupefy or kill the fish.
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.