However, the activity declined significantly from the third passage on (Fig. 1). Figure 1 Transformation of DON to DOM-1 by the subcultures of digesta samples . The digesta samples were from the large intestine of chickens fed clean or DON-contaminated wheat (10 μg g-1 DON) during the in vivo enrichment experiment. The subcultures were grown in L10 broth containing 100 μg ml-1 DON. Each subculture was incubated for 72 hours. n = 6. Selection for DON-transforming

bacteria When individual antibiotics were tested for bacterial selection (Step find more 3 in Fig. 2), virginiamycin, lincomycin, and tylosin showed no detrimental effect on either the activity of DON transformation or bacterial growth of the start cultures at all tested concentrations LDN-193189 purchase (Table 1). However, a similar effect was observed only at the low concentration (5 μg ml-1) of streptomycin, penicillin G, and salinomycin. Different combinations of these antibiotics were then investigated for their effect on https://www.selleckchem.com/products/torin-2.html supporting the activity of DON transformation and the growth of bacterial cells. Only one combination containing virginiamycin

(20 μg ml-1), lincomycin (60 μg ml-1), and salinomycin (5 μg ml-1) significantly reduced the growth of bacterial cells without detrimental effect on the DON-transforming activity. Hence, the cultures selected through this combination were used for further selection by the AIM+CecExt medium. Table 1 Effects of antibiotics on the growth and DON-transforming activity of bacteria from the large (LIC) or small (SIC) intestine. Antibiotics Final concen (μg/mL) LIC-S2   LIC-S3   SIC-S2   SIC-S3       Growth DON to DOM-1 (%)     Growth DON to DOM-1 (%)     No antibiotic 0 +++ 100.0 N/A   +++ 100.0 +++ 100.0 Streptomycin 100 +++ 49.3 +++ 25.6 +++ 44.3 +++ 5.8   50 +++ Etofibrate 100.0 +++ 30.8 +++ 48.7 +++ 11.4   5 +++

100.0 +++ 100.0 +++ 100.0 +++ 100.0 Gentamicin 80 +++ 18.1 +++ 6.0 ++ 44.0 +++ 7.1   40 +++ 23.5 +++ 6.5 +++ 44.8 +++ 7.4   5 +++ 100.0 +++ 22.5 +++ 46.5 +++ 6.8 Bacitracin 60 ++ 16.2 ++ 0.0 +++ 45.0 +++ 8.0   30 ++ 16.1 ++ 2.5 +++ 45.0 +++ 8.8   5 +++ 15.8 +++ 3.9 +++ 47.0 +++ 11.9 No antibiotic 0 +++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0 Penicillin G 100 + 12.1 +++ 1.5 ++ 100.0 + 35.5   50 + 12.7 +++ 7.4 ++ 100.0 + 44.1   5 ++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0 Virginiamycin 20 +++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0   10 +++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0   5 +++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0 Lincomycin hydrochloride 60 +++ 100.0 +++ 100.0 +++ 31.3 +++ 3.6   30 +++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0   5 +++ 100.0 +++ 100.0 +++ 47.3 +++ 100.0 No antibiotic 0 +++ 100.0 +++ 100.0 +++ 100.0 +++ 100.0 Salinomycin 80 +++ 16.7 +++ 2.0 +++ 55.2 +++ 8.9   40 +++ 18.0 +++ 4.0 +++ 89.2 +++ 80.9   5 +++ 16.8 +++ 100.0 +++ 100.0 +++ 100.0 Vancomycin 30 +++ 15.9 +++ 2.5 ++ 46.2 +++ 9.6   15 +++ 15.0 +++ 2.2 ++ 44.9 +++ 10.5   5 +++ 38.5 +++ 13.2 ++ 46.8 +++ 9.7 Carbadox 50 +++ 16.4 ++ 3.5 ++ 27.7 +++ 3.9   25 +++ 100.