Studies on the Mode of Action of Antileprous drugs

IV. Adsorption of DDS and the Relating Drugs on Bacteria

Abstract

The adsorption of DDS and the relating drugs on NQ bacilli and E. coli K-12 (CS-2) was examined by Batch Method.
The drugs employed were DDS³⁵, DADDS³⁵, DDS•-G, and four of non-labeled sulfaagents. These were separately dissolved into 5ml of calf serum or physiological saline in a concentration of 10μg/ml. The lyophilized bacilli of 15, 30, 60, 120mg each were suspended and centrifuged, after the vigorous agitation followed by 1 or 4 hours' shaking-incubation.
As the result, it was found that the adsorption of a drug on bacteria was parallel to a certain extent with the adsorptivity to serum and was also inhibited by the adsorptivity of the calf serum when it was put to use as a basal medium.
No influence could be found by the pre-treatment of NQ bacilli with 5% TCA or with ethanol-ether. Therefore, this adsorption is supposed to be merely non-specific one.
The adsorption of DDS³⁵ on the coli bacilli was higher than that on NQ bacilli, because the coli bacilli adsorbed DDS35 even in the calf serum. It may perhaps be due to the difference in the form of the bacterial clumps between the two strains.
The adsorption on an activated charcoal was superior to that on the two strains.
The adsorbed DDS³⁵ per 100mg of NQ bacilli was increased with the weight of NQ bacilli suspended into the saline. While, it was contrary decreased in the case of DADDS³⁵, suggesting the saturation in the earlier stage.
When it was used non-labeled Sulfaisoxazole, -dimethoxine, -methoxypyridazine, Sulfonamide, and DDS, a lowering in the optical density could be detected, though not so clearly noticed.
Based on this interactive adsorption and on a presumption concerning the more predominant out-flow of labile conjugates from capillary vessels than that of the stable conjugates, the drug action mechanism in the peripheral lesions was mentioned.