Kinetic studies on clavulanic acid degradation

The highest CA stability was found at slightly acid conditions (pH 6.2) and low temperature (10 °C).

“The highest CA stability was found at slightly acid conditions (pH 6.2) and low temperatures (10 °C).”

The trends of CA decomposition in fermentation broth seem to deviate from first and pseudo-first-order kinetics previously reported for CA solutions prepared with standard reactant or commercial formulations.

“The trends of CA decomposition in fermentation broth seem to deviate from first and pseudo-first-order kinetics previously reported for CA solutions prepared with standard reactant or commercial formulations [10,19,23,25,26,27].”

Previous studies have shown that CA stability increases at slightly acidic pH values.

“Previous studies have shown that CA stability increases at slightly acidic pH values [10,11]; several authors found a pH of 6.8 as favorable for obtaining high titers of CA in submerged cultures [5,7,9,12,13,14,15,16].”

Bersanetti et al. found that CA degradation at 10, 20, 25, 30, and 40 °C and pH 6.2 and 7.0 fitted an irreversible first-order kinetics relating the degradation rate constant to temperature.

“Bersanetti et al. [10] investigated CA degradation at 10, 20, 25, 30, and 40 °C and pH values of 6.2 and 7.0. The results fitted an irreversible first-order kinetics accounting for the relationship between the degradation rate constant and the temperature.”

CA is susceptible to moderate temperature increments, which accelerate the rate of degradation regardless of the source.

“CA is also susceptible to moderate temperature increments, since they accelerate the rate of degradation regardless of the source [10].”

CA originating from fermentation broth degraded faster than pure reagent and commercial medicine.

“It was also observed that CA which originated from fermentation broth, degraded faster than the pure reagent and the commercial medicine [10].”

The rate of CA degradation is susceptible to medium composition, exhibiting higher degradation rates in supplemented and complex media.

“The rate of CA degradation is susceptible to medium composition, exhibiting higher degradation rates in supplemented and complex media [10,11,16].”

The calculated Ea for the irreversible process of CA degradation is close to previous reports for CA in fermentation broths.

“The activation energy (Ea) calculated for the irreversible process of degradation was 16.512 kJ/mol which is close to previous reports for CA in fermentation broths [10,17].”