Allium Test for Antimitotic Effects and Brine Shrimp (Artemia salina) Lethality Test for Toxic Effects of Gotu kola (Centella asiatica) Leaf Methanolic Extract

Abstract

Due to the great number of still non-treatable kinds of cancer and their tendency to produce resistances during anti-cancer treatment, we are faced with a current need to find new compounds and new lead structures for cancer chemotherapeutical purposes (Alamjir, 2014). The study was conducted to determine whether or not the methanolic extract from Centella asiatica can cause antimitotic effects on onion root tip cells and exert toxic effects in brine shrimp larvae. Actively growing root tips were cut from onion bulbs and were treated in vitro for two hours with six treatments, namely: distilled water, 0.05% colchicine, woo ppm, loo ppm, io ppm and 1 ppm C. asiatica leaf methanolic extract. The result shows that the onion root tips treated with 0.05% colchicine had the highest mean percentage of cells with C-mitosis (75.6%), followed by moo ppm C. asiatica leaf methanolic extract (62.4%), 100 pmm (51.6%), 10 ppm (44.4%) and 1 ppm (35.6%). It showed that the plant extracts contain bioactive components that can induce spindle damage in dividing onion root tip cells and its effect is dose-dependent. The toxicity of three concentrations of the plant extracts was tested using the brine shrimp lethality assay with artificial sea water as negative control. The brine shrimps were first hatched and cultured for 24-48 hours and then subjected to the different treatments. The results showed that the brine shrimp tested with moo ppm has the highest mortality rate of 93% and 10 ppm has the lowest mortality rate of 6o%. The obtained mortality data were then subjected to probit analysis, and the results showed that C. asiatica has a medium lethal concentration of 3.652 ig/m1, with 95% confidence interval. It showed that plant extracts also contain cytotoxic components that can cause lethality to brine shrimp nauplii and its effect is also dose-dependent.