Anticancer and Antimicrobial Activities of New Cobalt and Zinc Complex-Derived Benzimidazole Containing Nitro or Methyl Groups

The cytotoxic effects of six newly synthesized 5(6)-methyl or 5(6)-nitrobenzimidazole-derived compounds that contain cobalt and zinc on nonsmall cell lung carcinoma (A549) and healthy lung epithelial (BEAS-2B) cell lines were evaluated by MTT, caspase-3, and Western Blotting methods. Cisplatin was also used as a reference compound. Compound <b>4</b> and compound <b>5</b> exhibited high cytotoxic activity against A549. While the IC₅₀ value of cisplatin was 14.31 μM, IC₅₀ values of compound <b>4</b> and compound <b>5</b> were 10.30 and 7.01 μM on A549 cells at 72 h, respectively. On the other hand, for BEAS-2B cells, the IC₅₀ values of cisplatin, compound <b>4,</b> and compound <b>5</b> were 5.91, 90.13, and 51,68 μM, respectively. The results showed that although compounds <b>4</b> and <b>5</b> have high cytotoxicity on A549 cells, similar to cisplatin, they are less cytotoxic to BEAS-2B cells than cisplatin. The antibacterial and antifungal properties of the synthesized compounds were also investigated using minimum inhibitory concentration method. Their antimicrobial activities were tested against the Gram-negative bacteria <i>Escherichia coli</i> ATCC 25922 and <i>Pseudomonas aeruginosa</i> ATCC 27853, Gram-positive <i>Staphylococcus aureus</i> ATCC 29213, and yeast species <i>Candida albicans</i> ATCC 90028 and <i>Candida tropicalis</i>. The compounds showed notable antimicrobial activity against these pathogenic bacteria and yeasts.