Cytotoxicity and genotoxicity of instant noodle seasoning extract on Allium cepa root

The increasing consumption of instant noodles has raised concerns about their potential health and environmental impacts. This study aimed to investigate the effects of instant noodle seasoning extract on the mitotic index of Allium cepa root tip. Using A. cepa as a model organism, the study compared the mitotic index under different treatments: distilled water (negative control), malathion (0.9 g/L) as (positive control), and instant noodle seasoning (73.3 g/L). The onion root tips were exposed to the treatments for 24 and 48 hours. Roots were fixed with ethanol-acetic acid and stained with 2% acetic-orcein for microscopic analysis. The mitotic index was calculated by counting the number of cells in mitosis out of the total observed cells. The results showed that instant noodle seasoning exhibited an initial mitotic index of 14.6% ± 0.04 in 24 hours, which significantly dropped to 7.4% ± 0.01 after 48 hours (p = 0.0018), meanwhile distilled water maintained a high mitotic index of 9.6% ± 0.01 at 24 hours, which increased to 15.2% ± 0.03 at 48 hours with p= 0.014. In contrast, malathion had the lowest mitotic index, starting at 7.6% ± 0.04 in 24 hours and decreased to 4.9% ± 0.01 at 48 hours but not significant. Furthermore, both malathion and instant noodle seasoning treatments resulted in various chromosomal aberrations, such as lagging chromosomes and chromosomal stickiness. Hence, these findings highlighted that instant noodle seasoning possesses cytotoxic properties that disrupt normal cell division, with more pronounced effects observed after 48 hours (p<0.05). This study shows the utility of Allium cepa as a sensitive model for evaluating the genotoxicity of food additives, offering critical insights into their potential impact on health. Further research is recommended to explore the specific mechanisms of toxicity, including long-term effects of chronic exposure and identification of the active components responsible for the observed cytotoxicity.