METHODOLOGY: All synthesized compounds were characterized by IR, NMR, Mass and elemental analysis followed by in vitro antimicrobial studies against Gram-positive (Staphylococcus aureus), Gram-negative (Salmonella typhi and Klebsiella pneumoniae) bacterial and fungal (Candida albicans and Aspergillus niger) strains by the tube dilution method. The in vitro anticancer evaluation was carried out against the human colorectal carcinoma cell line (HCT116), using the Sulforhodamine B assay.
RESULTS, DISCUSSION AND CONCLUSION: Compound W6 (MICsa, st, kp = 5.19 µM) emerged as a significant antibacterial agent against all tested bacterial strains i.e. Gram-positive (S. aureus), Gram-negative (S. typhi, K. pneumoniae) while compound W1 (MICca, an = 5.08 µM) was most potent against fungal strains (A. niger and C. albicans) and comparable to fluconazole (MIC = 8.16 µM). The anticancer screening demonstrated that compound W17 (IC50 = 4.12 µM) was most potent amongst the synthesized compounds and also more potent than the standard drug 5-FU (IC50 = 7.69 µM).
RESULTS AND DISCUSSION: The synthesized benzimidazole compounds were evaluated for their antimicrobial activity using the tube dilution method and were found to exhibit good antimicrobial potential against selected Gram negative and positive bacterial and fungal species. The compounds were also assessed for their anticancer activity exhibited using the SRB assay and were found to elicit antiproliferative activity against MCF7 breast cancer cell line, which was comparable to the standard drug.
CONCLUSION: Antimicrobial screening results indicated that compounds 1, 2 and 19 to be promising antimicrobial agents against selected microbial species and comparable to standard drugs which included norfloxacin and fluconazole. The anticancer screening results revealed that compounds, 12, 21, 22 and 29 to show the highest activity against MCF7 and their IC50 values were more potent than 5-fluorouracil.
CONCLUSION: Anticancer screening of the synthesized compounds using Sulforhodamine B (SRB) assay demonstrated that compounds 2y (IC50 = 0.01 µmol/mL) and 4y (IC50= 0.02 µmol/mL) have high antiproliferative potential against human colorectal carcinoma cancer cell line than the reference drug (5- fluorouracil) and these compounds also showed best dock score with better potency within the ATP binding pocket and may also be used lead for rational drug designing.
RESULTS AND DISCUSSION: The synthesized analogues were characterized by FT-IR, 1H/13C-NMR and MS studies as well C, H, N analysis. All synthesized compounds were evaluated for in vitro antibacterial activity against Gram-positive (B. subtilis), Gram-negative (E. coli, P. aeruginosa, K. pneumoniae and S. typhi) strains and in vitro antifungal activity against C. albicans and A. niger strains by serial dilution method, the minimum inhibitory concentration (MIC) described in μM/ml. The in vitro anticancer activity of synthesized compounds was determined against human colorectal carcinoma cell line (HCT- 116) using 5-fluorouracil as standard drug.
CONCLUSION: In general, most of the synthesized derivatives exhibited significant antimicrobial and anticancer activities. Compounds 8, 10, 15, 16, 17, 20 and 22 showed significant antimicrobial activity towards tested bacterial and fungal strains and compound 26 exhibited significant anticancer activity.