Listeria monocytogenes is a main etiological factor of listeriosis, spread mainly by food products. In recent years, an increasing number of patients with listeriosis and an augmentation in L. monocytogenes antibiotic resistance, e.g. to penicillin and ampicillin, has been reported. The aim of the study was to characterise the L. monocytogenes strains isolated from fish-processed food products. Species identification, based on the multiplex-PCR reaction, was performed, and the genetic similarity of the isolates was analysed with the RAPD technique. The strains, in the form of planktonic cells and a biofilm, were subjected to drugsusceptibility analysis, and the effect of disinfectants on the bacillus cells was evaluated. All of the analysed strains were of the Listeria monocytogenes species. Three genetically distant strains were detected, i.e. Lm I, Lm II and Lm III. Approximately 66.6% penicillin-resistant and 66.6% cotrimoxazole-resistant strains were found. No erythromycin-resistant strain was detected. The Lm II strain was simultaneously resistant to four antibiotics, i.e. penicillin, ampicillin, meropenem and cotrimoxazole. The strongest biofilm was formed on aluminium foil and the weakest on rubber. The tested disinfectant antibiofilm effectiveness was related to the type of surface. The most effective agent was paracetic acid and hydrogen peroxide (elimination rate 5.10-6.62 log CFU × cm −2 and 5.70-7.39 log CFU × cm −2 after 1-and 5-min exposure, respectively) and the least-sodium hydroxide (elimination rate 0.52-1.20 log CFU × cm −2 and 0.98-1.81 log CFU × cm −2 after 1-and 5-min exposure, respectively). Further studies on a greater number of L. monocytogenes strains are recommended.
Hygienic aspects of cattle slurry storage as tHe most popular and cHeapest metHod of Handling liquid animal excrements* * K r z y s z t o f S k o w r o n 1, 2♦ , H a l i n a O l s z e w s k a 2 , K a r o l i n a J a d w i g a S k o w r o n 3 , P i o t r P a l u s z a k 3 , B a r b a r a B r e z a -B o r u t a abstract slurry is a very valuable natural fertilizer, but its improper use in agriculture poses a serious sanitary threat. therefore its treatment before use for fertilization is advisable. one of such methods, which is still the most popular, is storage of liquid excrements. the aim of this study was to estimate the sanitization effectiveness of storage at 4ºc and 20ºc based on parameters describing the kinetics of changes in the population of some indicator bacteria in cattle slurry with different dry matter content. the material for the study was fresh cattle slurry. the liquid excrements used in the experiment had a dry matter content of 2, 6 and 14%. slurry was stored at 4ºc and 20ºc. Bacilli of Salmonella dublin, E. coli and enterococci were used as indicator bacteria. number of microorganisms was determined based on mpn method in a 3-tube design. Basic parameters of the bacteria inactivation kinetics were calculated and statistical analysis was made using the program sas 9.2 pl. in stored slurry a gradual elimination of all the studied microorganisms was observed. Hygienization effect of storage was smaller at 4ºc than at 20ºc and in excrements with a high dry matter content. depending on storage temperature and dry matter proportion, the theoretical times of survival ranged from 81.85 to 220.80 days for bacilli of Salmonella dublin, from 74.93 to 199.36 days for E. coli, and from 118.67 to 335.84 days for enterococci. the study showed explicitly that statutory time of slurry storage is insufficient to ensure its complete hygienization.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.