Camille Bowen, Contributor
JAMAICA'S AGRICULTURAL sector has been exploiting the ackee fruit with great success and today it is the fourth largest agricultural export crop. Between January and September last year, processed ackee exports passed the $300 million mark. These figures are not surprising because when most Jamaicans (at home and in the Diaspora) think about ackee they picture a highly decorated plate of delicate yellow fruit flavoured by various spices and garnished with indigenous condiments. Jamaicans crave this fruit.
The name ackee is derived from the West African Akye Fufo. Scientifically known as Blighia sapida, the fruit from the ackee tree is a highly celebrated item in the nation's culinary heritage, and has been massaging the palates of Jamaicans for many years.
But as we will demonstrate in this article, ackee is an extremely versatile fruit with the potential for development into a pharmaceutical.
The edible part of the fruit, called the arilli, is not its only important attribute. The fruit is also comprised of a pod which encapsulates typically three yellow arilli, each attached to a shiny, black seed. The pink raphe attaches the pod to the arilli. The pod is the largest part of the fruit, followed by the seeds, arilli and raphe respectively.
ACKEE PODS AS SOAP AND COSMETIC
Ackee pods were used for laundry in times of scarcity. Innovative women trying to cope with the lack of washing soap would remove the pods and rub them on the clothing. It produced suds and left the clothes clean. This cleaning property is due to the high levels of saponins in the pods. Several saponins have been isolated from the ackee pod and characterised as part of our research on the ackee fruit being carried out at the Department of Chemistry of the University of the West Indies (UWI). Many plant species contain saponins, which may be present in leaves, fruits, stems or roots. Ackees actually belong to a family of plants, Sapindaceae, (soapberry family) known for their soapy characteristics.
Extracts of ackee pods have also been utilised as cosmetics. In fact, a poultice of ackee pods have in times past been used in the treatment of skin infections. We can explain this application on the basis of the saponins in the ackee pods. In addition our research at UWI has shown that the ackee pod contains polyphenolic antioxidants in significant quantities. These antioxidants could also contribute to the use of the pods for cosmetics.
ACKEE AS PESTICIDE
Ackee seeds are not merely to be discarded, as they can be beneficial in several ways. Research done by the Natural Products Institute, UWI, shows that the oil extracted from the seeds has pesticidal properties, being active against the cattle tick and sweet potato weevil. The oil from the arilli was tested and found to be even more effective. The major triglyceride (a simple fat compound) present in ackee arilli was identified by our research group as 1,2-dioleylpalmitin, and was shown to be active against sweet potato weevil. Use of these botanical formulations could lead to a reduction in the use of chemical agents which have the potential of being hazardous to both the consumer and the environment.
PHARMACOLOGICAL APPLICATIONS
Hypoglycin A reduces blood sugar to extremely low levels. Current international pharmacological research is geared towards exploiting the hypoglycaemic property of hypoglycin A with the hope of applying it to the treatment of diabetes, which is one of the leading causes of deaths in Jamaica. Hypoglycin A is now being used as a template in the preparation of structurally similar compounds. It is hoped that these products, based on hypoglycin A, will have increased hypoglycaemic activity with a reduced level of toxicity. Potentially these compounds could become new pharmaceuticals for the treatment of diabetes.
All of the above indicate that there is a compelling case for further research to be undertaken into the ackee fruit.
Nature makes ripe ackee safe
Unripe ackee arilli and seeds contain hypoglycin A, a toxic, non-proteinogenic amino acid. However, nature has ensured that as the fruit ripens it becomes safe for consumption. Our research revealed that the level of hypoglycin A in the arilli is reduced by a factor of 13 as the fruit matures. The ripe fruit is therefore totally safe for consumption, as not only is hypoglycin A at a low level, but being highly soluble in water, it is further removed upon boiling. As the fruit matures, the level of the related but less toxic compound, hypoglycin B, found only in the seeds, increases 7-fold. It is therefore proposed that as maturity ensues, hypoglycin A is translocated to the seed where it combines with a harmless amino acid, glutamic acid, to form hypoglycin B, which poses no threat to consumers.
