Nutritional and Spectral Characteristics of Terminalia Plants

Aims: Terminalia spp. is medicinal plants that belong to Combretaceae family, widely used in traditional Ayurvedic medicine. In this work, the nutritional constituents of the leaves, seed kernel and seed coat from four Terminalia species (T. arjuna, T. bellirica, T. catappa and T. chebula) are reported.

Methodology: Polyphenol and flavonoid contents were analyzed spectrophotometrically by using Folin-Ciocalteu and aluminum chloride as reagents, respectively; mineral contents were quantified by using X-ray fluorescence; and the functional groups of the phytochemicals were investigated by infrared spectroscopy.

Results: The total concentration of 20 macro- and micronutrients and heavy metals (viz. P, S, Cl, K, Rb, Mg, Ca, Sr, Ba, Al, Ti, Cr, Mn, Fe, Co, Cu, Zn, Mo, As and Pb), and the total polyphenol and flavonoid contents in the seed kernels ranged from 1754 to 65521 mg/kg, from 2150 to 51100 mg/kg and from 63 to 42300 mg/kg, respectively. Polyphenol and mineral contents for the Terminalia spp. seed coats and leaves were also determined. The enrichment in each of aforementioned elements with respect to the soil content was calculated. The vibrational spectra of the leaves and seed coats agreed with a composition rich in lignin, hemicellulose, cutin, pectin and flavonoids, while those of the seed kernels were in accordance with the presence of unsaturated oils, protein, and fiber.

Conclusion: Various parts of the four Terminalia species under study (T. arjuna, T. bellirica, T. catappa and T. chebula) featured high contents of nutrients and polyphenols needed for biological metabolism and human health. In addition, heavy metals were only present at traces level, indicating that these Terminalia plants would be safe for medicinal uses.