Fig. 2: In vitro anti-ureolytic activities of hydroxamic acid (HA) derivatives and stability of 2-octynohydroxamic acid (2-octynoHA).

a, b Concentrations of ammonia produced from urea hydrolysis in caecal content after 30 min incubation with (a) saturated HAs (n = 2 for 1 mM and 40 mM acetohydroxamic acid (AHA), n = 3 for 5 – 20 mM AHA; n = 3 for 0.05 – 20 mM heptanohydroxamic acid (HHA) and octanohydroxamic acid (OHA), n = 6 for the negative control (0 mM) for HHA and OHA; n = 4 for nonanohydroxamic acid (NHA) and decanohydroxamic acid (DHA); n = 3 for laurohydroxamic acid (LHA)) and (b) unsaturated HAs (n = 3 for 2-octynoHA, trans-2-octenohydroxamic acid (2-octenoHA), 3-octynohydroxamic acid (3-octynoHA), 7-octynohydroxamic acid (7-octynoHA); n = 6 for trans-3-octenohydroxamic acid (3-octenoHA); n = 11 for OHA). c In vitro anti-ureolytic activities of 2-octynoHA, OHA and AHA toward Jack bean urease. T₅₀ is the time when the absorbance value of a sample with an inhibitor equals to half of the maximum absorbance of a corresponding control sample (A_1/2) (n = 4 for 2-octynoHA and OHA; n = 3 for AHA). d Activities of 2-octynoHA, OHA and AHA at 0.1 mM. ΔT₅₀ is defined as the time by which A_1/2 is delayed in the presence of an inhibitor at 0.1 mM (n = 4 for 2-octynoHA and OHA; n = 3 for AHA). e Stability of 2-octynoHA over 12 h incubation at 37 °C in phosphate buffer at pH 6.8 and pH 6.3 (n = 3). Data are expressed as mean ± standard deviation (SD) from n experiments. Source data are provided as a Source Data file.