Effect of Phaulopsis falcisepala (Acanthaceae) Leaves and Stems on Mitotic Arrest and Induction of Chromosomal Changes in Meristematic Cells of Allium Cepa

< p>Phaulopsis falcisepala is an herb found in the forest zone of West Africa. It is applied ethnomedicinally for treating wounds and cancer. This study investigated the chemical constituents, cytotoxicity, and antimitotic activity of P. falcisepala leaves and stems. Chemical constituents were evaluated using phytochemical methods. Cytotoxicity was investigated using brine shrimp lethality and Allium cepa root growth inhibition assays. Antimitotic activity and induction of chromosomal aberrations were assessed by cytological examination of treated A. cepa meristematic cells. Chemical investigation revealed the presence of diverse bioactive chemical groups, including alkaloids, terpenoids, tannins, flavonoids and saponins in various extracts of the leaves and stems of P. falcisepala. Aqueous and methanol extracts contained copious amounts of the phytochemicals while ethyl acetate and n-hexane extracts contained moderate to trace amounts. The extracts demonstrated toxicity against brine shrimps, with LC۵۰ values in the range ۱۳.۱–۵۲.۲ µg/mL. The extracts significantly inhibited A. cepa root growth, with IC۵۰ values in the range ۶۳.۹۱–۸۷.۴ µg/mL and ۴۵.۳۴– ۸۱.۱۵µg/mL for ۲۴ and ۴۸ h treatments. The extracts (IC۵۰ values in the range ۴۶.۲–۹۴.۲۳ µg/mL and ۳۰.۷۹–۷۵.۸۱ µg/mL for ۲۴ and ۴۸ h treatments) produced significant antimitotic effect comparable to or greater than that of methotrexate (IC۵۰ value >۱۲۵ µg/mL). Cytological examinations revealed that the extracts induced mitotic arrest and chromosomal changes. This study reports for the first time the phytoconstituents and cytotoxic activity of P. falcisepala supporting its ethnomedicinal use and could serve as the basis for further pharmacological studies and isolation of bioactive principles.

Keywords:

Phaulopsis falcisepala , Cytotoxicity , Antimitotic , Allium cepa , Chromosome aberration , cancer