2004 Volume 9 Issue 4 Pages 95-103
We synthesized a new bis-quaternary ammonium compound (bis-QAC), 4, 4'-(1, 6-dioxyhexamethylene) bis (1-alkylpyridinium halide) s (4DOBP-6-n-X) (alkyl chain length, n=6, 8, 10, 12, 14, 16 and 18, X=Br or I) that has a symmetrical dimeric structure, and is composed of two alkylpyridinium halides connected with a dioxyhexamethylene. We examined the relationship of the hydrophobicity and antimicrobial activity using 4DOBP-6-n-X. The influences of pH, temperature, and hemolytic activity were then measured using 4, 4'-(1, 6-dioxyhexamethylene) bis (octylpyridinium bromide) (4DOBP-6-8-Br) which showed a superior antimicrobial activity among the 4DOBP-6-n-X series. The following three chemical compounds were used as a comparison: 4, 4'-(1, 6-dithiohexamethylene) bis (octylpyridinium bromide) (4DTBP-6-8-Br) which is considered as an excellent antimicrobial agent based on a previous report, alkylbenzyldimethyl ammonium chloride (BAC) and 2-(4'-thiazolyl) benzimida-zole (TBZ). In the results of the experiment, 4DOBP-6-8-Br exhibited a wide antimicrobial spectrum, and had a strong activity against bacteria and fungi comparable to 4DTBP-6-8-Br. The hemolytic activities of 4DOBP-6-8-Br and 4DTBP-6-8-Br were almost same, and lower than that of BAC. 4DTBP-6-8-Br had some defects in that it colored metals or generated a bad smell and a hazardous gas; however, in 4DOBP-6-n-X, these disadvantages were not present. 4DOBP-6-n-X seems to be an environmentally friendly antibacterial agent.
