Evaluation of Cytotoxic Effects of Methanolic Extract and Fractions of Mirabilis jalapa (L.) Leaf

This study examined the potential cytotoxicity of Mirabilis jalapa L. methanolic crude leaf extract and its fractions against brine shrimp nauplii (Artemia salina L.) and Allium cepa L. roots. The leaf extraction was done according to standard technique and crude extract was partitioned using n-hexane, water, ethyl acetate and butanol to obtain their respective fractions. Allium cepa root growth inhibition of M. jalapa methanolic crude extract and fractions were evaluated as well as brine shrimp lethality of the fractions based on standard methods. Also, phytochemical screening of the methanolic crude leaf extract was carried out according to standard methods. The result showed that M. jalapa methanolic crude leaf extract caused a significant reduction in cell mitotic index (32.96%) compared with the control (52.13%). The butanol fraction produced the highest mitotic inhibitory activity on A. cepa cell division at 0.3 mg/ml. Moreover, the butanol fraction produced the highest percentage lethality (LC50 1.45 μg/ml) against brine shrimp nauplii. There was a strong correlation between brine shrimp lethality and mitotic cell inhibition with butanol fraction as the most potent in both models. The methanolic leaf crude extract tested positive for alkaloids, cardiac glycosides, flavonoids, saponins, steroids, tanins and triterpenes. The methanolic crude extract of M. jalapa leaf and its fractions exhibited effective cytotoxic effect on A. cepa and brine shrimps. Butanol fraction, with the most cytotoxic activity among the tested extracts, demonstrates a promising source for novel anticancer agents.