Medicinal : Swietenia macrophylla - Skyfruit

Swietenia macrophylla is commonly known as big-leaf-mahogany, Honduras mahogany etc.  The generic name commemorates Gerard von Swieten ( 1700-1772), a botanist and physician to Maria Theresa of Austria.  The specific name means large leaves from Greek words makros ‘large’, and phyllon ‘leaf’.

Its fruit is known as sky fruit, 向天果 (Mandarin), tunjuk langit (Malay). 

The fruit is a woody capsule, about 12.5 x 7.5 cm, erect, oblong.  The outer valves are thick and becoming woody when mature.  When dry the 5-valved fruits split open from the base.  The center of the fruit is a thick woody 5 angled columella extending to the apex from which the seeds hang pendulous by their wing. 

Fruiting occurs annually.

There are about 35-45 seeds per fruit.  Seeds are of  woody coloured at 7.5-12cm in length with wings.  Seeds disperse via wind, average dispersal distance of 32-36m, with maximum distance over 80m.

In its origin of South America, the seeds of Swietenia macrophylla are traditionally used  in treating hypertension, diabetes, malaria, typhoid, diarrheal, pain-killer, leishmaniasis and abortion.  The seeds are usually consumed raw by chewing, or by infusion.

The seeds are extremely bitter in taste, which is caused by swietenolide.

Extract of the seeds were found to contain many kinds of tetranortripenoids, fatty acids, terpenoids,  swietenine and its derivatives.

Researches show that extract of various parts of S. macrophylla to have anti-diarrhoeal, anti-gastric, anti-inflammatory, anti-nociceptive and anti-carcinogenic properties.

Swietenine, a tetranortriterpenoid, isolated from the Swietenia macrophylla seeds was found to have anti-diabetic effect on induced type II diabetic rats.

Methanol, dichloromethane and n-hexane were found to have anti-bacterial, anti-fungal and anti-oxidant properties.

A lection isolated from the leaves was cytotoxic against Acanthamoeba sp and Tetrahymena pyriformis.

However, further investigations are needed to verify these findings.  Claims made by unregistered herbal practitioners, direct sales or hearsays are not to be taken seriously.