Outside Papua Island, the name Rabon bi probably sounds unfamiliar or even unknown. However, this unique fruit plant is widely popular among the natives who live particularly close to the tropical coasts in Papua and West Papua. Another unique thing is that the local people do not consume it, regardless it is fruit by name. They otherwise use it for other purposes and also as a source of medicines.
What do others call it?
The full scientific name for Rabon bi is Barringtonia asiatica (L.) Kurz. Many have used only Barringtonia asiatica to refer to this plant. The trees are native to mangrove habitats and widely spread on tropical seashores and islands.
Native people of western Indian Ocean regions, Asia, and western Pacific Ocean islands are familiar with this fruit plant. They even have uniquely different local names for it.
In Indonesia, Javanese and Sundanese call it Keben or Butun. Keben is also the second name the Papuans give to this fruit. Similarly, the Balinese name it Keben-keben. Meanwhile, it is Bitung in northern Sulawesi.
This fruit has nearly similar labels in other Southeast Asia countries. In Malaysia, it is generally Putat Laut, while in Malaya (Peninsular Malaysia) area, they are Butong or Putat Ayer. Move to the Philippines (Tagalog), it is Botong, Boton, and Bitung. It is Kyi-git in Myanmar, Chik ta lae or Don ta lae in Thailand, and Bàng quả vuông in Vietnam.
Due to the unique box-like shape, people in some parts of India call this fruit Box Fruit. As for the people in Plitty and Manus Province (Papua New Guinea), this fruit bears a name as Maliou.
The list can be longer for other vernacular labels of this fruit in other regions. However, people generally call it in English designation as Sea Poison or Sea Putat.
Where do they grow?
As native to tropical mangrove habitats, it is common to see Barringtonia asiatica trees with their fruits floating and drifting in the water make them widely spread to other beaches and islands. The habitat makes them nearly exclusively coastal species. Its distribution stretches from the Indian Ocean to Asia and Pacific Ocean littoral regions.
In Papua and West Papua, Rabon bi is one of the typical seashore vegetation. These plants naturally grow on sandy shorelines or coral-sand surfaces. In some other localities, they can even grow on the deeper inland, typically on limestone cliffs or hills, along the streams or in mangrove wetlands at sea level (sometimes up to an altitude of 350 meters).
What are the physical characteristics?
A Rabon bi tree can grow to an average height of 7 to 20 meters or reaches up to surprisingly as high as 30 meters. It is a soft hardwood in type with a characteristical diameter of 25 to 200 centimeters. There are bent stems with branches located lower at the bottom of the trunk that seems like approaching the ground.
The leaves have obovate-oblong or narrow-obovate shapes. Each leave is usually 20 to 40 cm (sometimes can reach 25 – 60 cm in length) long and 10 to 20 cm wide. They belong to pinnate leaves showing dark green color. The leave meat is quite thick with a smooth surface.
Before the fruit is coming, there are the flowers. The new blooms are distinctly beautiful with nice fragrances, especially at night-blooming. They appear at the end of the branch in white color with pinkish shades.
Now is time for the fruit. It grows naturally at the end of the stalk with smooth and slightly slippery skin. The Young fruits have a rectangular, stupa-like shape and green color. The older or mature fruit will show a more obvious rectangular or box shape. The color will turn brown for the ripe ones, where the weight will also be lighter.
What are the benefits?
Despite its name and category as fruit, it is rare to see Rabon bi as an edible foodstuff. The main reason is the active poisonous substances, including saponins, found in this fruit. As a result, people have used it for other purposes. They can use all parts, the fruit, the leaves, the seeds, the nuts, or the trunks.
Due to the existence of saponins, most natives in Indonesia (especially Papua), the Philippines, India or Indo-China use this fruit as fish anaesthesia or fish poison. They grind the fruit seeds into powder. The purpose is for easy fish capture by stunning, suffocating or killing the fish without affecting the flesh.
The local Papuan frequently apply this keben fruit as traditional medication. The most popular use is for eye medicine. Other applications are medicines for stomach aches, headache, sore throat, rheumatic, coughs, and more. They can also apply it as an external wound treatment.
As for food, the people in Indo-Chine consume young fruits as vegetables after a prolonged cooking process.
It seems that we are getting familiar with this uniquely exotic flora. To sum up, Rabon bi is a typical fruit plant from the tropical coastlines of Papua and West Papua. It has a unique name with different labels in different localities. It has a unique box or rectangular shape. Most importantly, this fruit plant offers numerous unexpected benefits.
