Saadullah^{1, 2}, Aziza Sultana¹, Md. Najem Uddin^{1, 3}, Md. Atikur Rahman¹, Most. Reshma Akter^{1, 4}, Ismot Ara Shathi^{1, 5}, Mst. Bobita Yeasmin¹, Md. Mahadi Hasan Lavlu¹, Monika Rani Saha¹, Aktar Uzzaman Chouduri^1,

Introduction: Vegetables are excellent sources of bioactive compounds with multidimensional therapeutic potentials including UTIs. Uropathogenic bacteria Proteus plays a crucial role in the development of UTI or catheter-associated UTI. By decomposing the urea of human urine, it can cause catheter encrustation. Objective: This study investigated the antiureolytic and anticancer activities of fifteen vegetables and spinaches. Materials and methods: The enzyme urease was purified from uropathogen Proteus mirabilis by ion exchange column chromatography. Thirty aqueous and petroleum ether extracts from fifteen vegetables were tested to inhibit bacterial urease. Results: The extracts of Allium cepa tuber robustly inhibited urea hydrolyzing activity of urease followed by Brassica oleracia flower and Lablab niger fruit. The urease inhibitor compound designated as E8 in Allium cepa tuber was identified as a nonflavonoid polyphenol. The MIC of E8 for the inhibition of urease was estimated at 0.39µg/ml and the E8-mediated inhibition of urease was enzyme-specific, i.e., mechanism-based directed, not the active site-directed. E8 might have a high affinity to urease. The compound E8 also had anticancer activity against the lung cancer cell line A549 which predominantly stopped the cell division of A549 cells at the cytokinesis stage in a dose-dependent manner compared to the standard doxorubicin. The IC₅₀ value of E8 for cancer cell proliferation was calculated at 160µg/ml from a regression line. Conclusion: The phenolic compound E8 of Allium cepa tuber can be a therapeutic agent for the target of lung cancer and kidney stone prevention.

Allium cepa tuber, polyphenol, antiureolytic, anticancer activity