Nalidixic acid sodium salt

Nalidixic acid (1) gives with 2-naphthol a yellow charge-transfer complex. The 7-methyl group of 1 condenses with vanillin (2) and Ehrlich's reagent (4) to the coloured (E)-benzylidene compounds 3 and 5. Treating 1 with thionyl chloride and subsequent reaction with aminopyrazolone (6) and sodium acetate leads to a mixture of trichloronalidixic acid (7) and its 3-carboxamide 8. The trichloromethyl group of 7 is converted with 6 in pyridine to form the amide 9. Nalidixic acid reacts with 1,3-dimethylbarbituric acid (10) in acetanhydride/acetic acid to yield the polymethine dyes 11-13, whose structures are confirmed by X-ray crystal structure analysis. The dyes 3 and 12 inhibit the growth of staphylococcus aureus and Escherichia coli, respectively.

Studies were conducted to evaluate the efficacy of a commercial blend of sulfuric acid and sodium sulfate (SSS) in reducing Salmonella on inoculated whole chilled chicken wings and to compare its efficacy to peroxyacetic acid (PAA) and cetylpyridinium chloride (CPC). Wings were spot inoculated (5 to 6 log CFU/ml of sample rinsate) with a five-strain mixture of novobiocin- and nalidixic acid-resistant Salmonella and then left untreated (control) or treated by immersing individual wings in 350 ml of antimicrobial solution. An initial study evaluated two treatment immersion times, 10 and 20 s, of SSS (pH 1.1) and compared cell recoveries following rinsing of treated samples with buffered peptone water or Dey/Engley neutralizing broth. In a second study, inoculated wings were treated with SSS (pH 1.1; 20 s), PAA (700 ppm, 20 s), or CPC (4,000 ppm, 10 s) and analyzed for survivors immediately after treatment (0 h) and after 24 h of aerobic storage at 4°C. Color and pH analyses were also conducted in the latter study. Recovery of Salmonella survivors following treatment with SSS (10 or 20 s) was not (P ≥ 0.05) affected by the type of cell recovery rinse solution (buffered peptone water or Dey/Engley neutralizing broth), but there was an effect (P < 0.05) of SSS treatment time. Immersion of samples for 10 or 20 s in SSS resulted in pathogen reductions of 0.8 to 0.9 and 1.1 to 1.2 log CFU/ml, respectively. Results of the second study showed that there was an interaction (P < 0.05) between antimicrobial type and storage time. Efficacy against Salmonella at 0 h increased in the order CPC , SSS , PAA; however, after 24 h of aerobic storage, pathogen counts of SSS- and PAA-treated wings did not differ (P ≥ 0.05). Overall, the results indicated that SSS applied at pH 1.1 for 20 s was an effective antimicrobial intervention to reduce Salmonella contamination on chicken wings.

The effect of different concentrations of some selected salts, namely, sodium chloride, potassium chloride, ammonium chloride, monosodium dihydrogen phosphate, calcium chloride, dibasic sodium phosphate, sodium sulphate, aluminium chloride and sodium citrate on the antimicrobial activity of nalidixic acid was investigated. It was found that all the salts tested, except aluminium chloride and sodium citrate, exert no antimicrobial activity. The effect of 10% non-ionic surface active agents, namely, Myrj 51, 52, 59, Brij 35, 58, 98, Tween 20, 40, 60, and 80 on the antimicrobial activity of nalidixic acid was studied. The results indicated that the activity of nalidixic acid was decreased in the presence of these surfactants. Furthermore, the effect of different concentrations of sodium chloride on the antimicrobial activity of nalidixic acid-surfactants systems was reported.