Phytochemistry — Bael (Aegle marmelos)– an Ayurvedic medicinal plant with a delicious fruit
Bael trees (Bengal quince/ Stone Apple) are native to the Indian subcontinent and Southeast Asia and belong to the Rutaceae family of plants. It produces an edible fruit with a hard woody shell and an orange-colored soft pulp. The juice of this naturally sweetened pulp is delicious and recommended for gut health.
The tree has a unique leaf structure with three leaflets like a trident. Indian Ayurvedic formulations use multiple components of the Bael tree (bark, root, leaves, and fruit pulp) to treat ailments. Treating gastrointestinal illnesses is one of the frequent applications found in traditional medicine. Besides, pharmacological studies on Bael fruit, leaf, and bark extracts showed potential anti-diabetic, antioxidant, anti-tumor, and anti-inflammatory properties (see references).
Dr. Asima Chatterjee (University of Calcutta) studied phytochemistry throughout her stellar career while identifying chemical components in medicinal plants. In 1949, her research group conducted structure elucidation of multiple furanocoumarin constituents isolated from the bark of the Bael tree. She discovered a new species named marmesin.
The time and resources might not have allowed fancy spectroscopic evaluation, but with the power of collaboration, she established the chemical structure of marmesin. Her group outsourced an authentic sample of D-nodakenetin (another structural form of marmesin) from Dr. W. Grüber (University of Vienna) and compared the physical and chemical properties of the two to confirm the isolated constituent as L-nodakenetin (marmesin). (The letters D and L are used in chemistry to define two different structures of one molecule; for example, you can think of the difference between your right and left hand). A plant called Angelica decursiva also produces nodakenetin, which exhibits anti-inflammatory and anti-tumor activity.
In her publication in 1949, Dr. Chatterjee also mentioned the presence of gamma-fagarine in the bark extract of Aegle marmelos. Gamma-Fagarine is a furanoquinoline alkaloid and found in other plants of the Rutaceae family. This alkaloid exhibits strong activity against hepatitis C virus (HCV) with a half-maximal inhibitory concentration (IC50) of 20.4 µg/ml.
Later studies on Bael fruit extract revealed another furanocoumarin compound called marmelosin. Recent pharmacological evaluations have shown that marmelosin possesses potent antioxidant activity. Moreover, this natural coumarin also displayed potent anti-inflammatory and anticancer properties.
Dr. Chatterjee was the first woman to get a Ph.D. from an Indian University. Her notable works include structure elucidation of Rauwolfia alkaloids, vinca alkaloids, flavonoid natural products, identification of anti-epileptic phytomedicine, and many more. Stay tuned for more stories about her lifetime work on structure determination of biologically active phytochemicals.
References:
Image Credit: Bael tree, Bael fruit, Dr. Asima Chatterjee
