December 30, 2018

Beyond The Botanical: The Dysoxylum Pod, Versatility Encapsulated...

When it comes to botanicals, there are some which are just incredibly attractive to look at, rendering them perfect "hardscape components." There are others which are purely for "utility" purposes...And then, there are those "in between" ones, which have elements of both.

Enter our friend, the Dysoxylum Pod.

We've talked a lot about the concept of allochtonous input in tropical flooded forest and stream ecosystems- the processes by which food from external sources- typically, trees and shrubs, falls into the water, providing supplemental food for the resident fishes.

This botanical is a "dead ringer" for many of the aforementioned materials...

Hailing from the family, Meliaceae, this pod has an interesting "back story" and etymology. Like so many botanicals, the Latin name of the genus describes important characteristics of the plant from which it comes. In this instance, The etymology of its genus, Dysoxylum derives from the Greek word ‘Dys’ -meaning "bad"- referring to "ill-smelling" and ‘Xylon’ meaning "wood."

So, "stinky wood." Awesome! (Have you noticed that the Latin roots of several of the botanicals we've covered so far refer to bad-smelling stuff? Yeah, I have.)

There are about 80 recognized species in this genus; we're officially in love with just one of them, Dysoxylum binectariferum, which is found in the forests of tropical India, but ranges as far afield as Vietnam. It's found in in alluvial soil conditions (clay and sand) and along rivers and streams...right up our proverbial "alley", huh?

In India, it is also known by many other names such as, "Indian White Cedar", "Bili devdari", "Bombay White Cedar", "Velley Agil", "Porapa", "Vella agil", and "Devagarige."

But "stinky." Really?

That being said, there is nothing stinky about the botanicals which come from this tree. The tree is an important component of tropical rain forests, typically from India, but found in other regions.

The tree grows to height of 120feet/40 m height, has bark which is greyish-yellow in color, with inner bark a creamy yellow color. Its leaves alternate or "sub-opposite", and are what botanists refer to as "abruptly pinnate." The tree has interesting flowers, which mature during February–April. They are greenish yellow in color and bisexual. The fruits that ripen during June–July are capsules.

In India, apart from its economic importance for building and furniture making, it is an important ingredient in traditional medicine. The fruit has a chemical composition known by the name “ashtagandha”, which means "fragrant smell", and is used for making incense sticks that are commonly used for worship.

Interestingly, compounds derived from the tree are also known by modern medical researchers to have extremely valuable medicinal properties...

Dysoxylum binectariferum bark was identified as an alternative source of CPT, through a process of bioassay-guided isolation. Camptothecin ( known to clinical researchers as "CPT 1") is a potent anticancer product, which led to the discovery of two other clinically used anticancer drugs, Topotecan and Irinotecan.

Rohitukine is another compound that accumulates in a significant amount in seeds, trunk bark, leaves, twigs, and fruits of D. binectariferum. Rohitukine is an important precursor for the synthesis of other potential anticancer drugs

Wow!

And all I wanted was some cool-looking seed pods for aquariums! With all of those medicinal uses, has anyone ever used them before in aquariums before we started playing with them for this purpose?

I'm doubtful, but you never know...

Now, what we call a "pod" is really the woody fruit capsule of Dysoxylum binectariferum. Botanists will tell you that the fruit capsule is 5-8 x 6 cm in length, red, "obovoid", depressed at the apex, and smooth in texture.

We'll tell you that it really looks like the kids of fruits and seed pods that you'd find in a flooded forest of South America, although its geographic distribution would make the case for it being a great addition to an aquarium representing Southeast Asia!

One thing that is cool about this botanical is that the outer surface remains quite firm, while the inside will soften and ultimately attract significant biofilms once submerged. We've found over the years that ornamental shrimp, in particular, really take a liking to these pods, devouring the soft interior and the resulting biofilms which it recruits over time.

"Stinky" it most definitely is not. Useful, interesting..and apparently tasty (if you're a shrimp), it is!

Preparation is pretty straightforward..Dysoxylum pods require boiling in order to get it to saturate and sink. This serves the dual purpose of softening the interior a bit, rendering them more easily consumed by the aforementioned creatures who graze on them. You'll have to boil these for at least an hour to get them saturated enough to sink. Even longer, sometimes- as they are surprisingly buoyant!

For interest, utility, and sheer "appropriateness" for inclusion in the aquariums we work with, it's hard to imagine a better pod than this one!

And that's more than you've probably ever heard about this little botanical rock star! And there is always just a bit more to learn when we go "behind the botanical", isn't there?

Until next time...

Stay creative. Stay thoughtful. Stay fascinated. Stay diligent...

And Stay Wet.

Scott Fellman

Tannin Aquatics