Justicia adhatoda L. vasicin and vasicinone as bioactive phytochemical compounds: Isolation, characterization, and computational studies

Abstract

Justicia adhatoda L. has wide applications in traditional and modern medicine. Its major potency is due to the presence of two alkaloids viz. Vasicine and Vasicinone. In industry, the demand for both marker compounds as well as quality Justicia adhatoda L. material is very high. The isolation of bioactive phytochemical compounds for the development of an in-house phytochemical reference standard library to verify quality control is of prime demand for an analytical chemist. For these reasons, the objective of the present study was to isolate two members of the alkaloids Vasicine and Vasicinone marker compounds from Justicia adhatoda L. Extraction was carried out by using a cold percolation method in a successive manner by increasing the order of polarity of the solvents from petroleum-ether to ethanol. Isolation was achieved for the above said two maker compounds by using separation, purification though column chromatography on silica-gel using mobile phase chloroform, and ethanol. Characterization of the isolated compounds was carried out by UV–VIS, IR, 1H NMR, 13C NMR and mass spectroscopy techniques. The isolated and purified solid compounds were confirmed as Vasicine and Vasicinone by comparison and co-relating with observed spectroscopy data and literature data. The compounds had a good to high amount of yield (0.4 % to 0.63 %) with high purity (98–100 %) through HPL. Lastly, frontier molecular orbital analysis (HOMO and LUMO), and global descriptive parameters (such as chemical potential, electronegativity, hardness, softness, etc.) were analyzed using computational approaches. Results revealed a good correlation with experimental data except for a few alternations in 1H NMR data.

Keywords

• Alkaloids
• Justicia adhatoda
• IR
• NMR
• Computational
• HPLC