Environmental exposure to heavy metals seriously threatens children’s health, potentially impacting the cardiovascular system. Mechanisms such as oxidative stress, inflammation, and lipid metabolism disturbances play a significant role in this process. Although cardiovascular diseases typically manifest in adulthood, an increasing number of studies suggest that their origins trace back to childhood and result from long-term pathophysiological changes. Therefore, early identification of modifiable risk factors is crucial for effective preventive measures and reducing future health risks.

A new method for determination of the optimum temperature and activation energies based on an idea of the average rate of enzymatic reaction has been developed. A mathematical model describing the effect of temperature on a dimensionless activity for enzyme deactivation following the first-order kinetics has been derived. The necessary condition for existence of the function extreme of the optimal temperature has been applied in the model. The developed method has been verified using the experimental data for inulinase from Kluyveromyces marxianus.

Amylases have potential application, inter alia, in processes with starch hydrolysis. The present paper reports the estimation of the optimum temperatures, the activation and deactivation energies of starch hydrolysis by $${\alpha }$$α -amylase Bacillus spp. The literature activity of $${\alpha }$$α -amylase Bacillus spp. versus temperature curves was analyzed. The mathematical model presented the activity of $${\alpha }$$α -amylase Bacillus spp. and the starch hydrolysis. Both the starch hydrolysis and the deactivation process of $${\alpha }$$α -amylase were analyzed by the first-order equations according to the enzyme concentration. Determined optimum temperatures $${T}_\textrm{opt}$$T opt were in the range from $$323.67 \pm 1.48$$323.67 ± 1.48 K to $$354.00 \pm 2.27$$354.00 ± 2.27 K, activation energies $$E_\textrm{r}$$E r were in the range from $$18.01 \pm 7.22$$18.01 ± 7.22 kJ mol^-1 to $$102.85 \pm 20.53$$102.85 ± 20.53 kJ mol^-1, and the values of deactivation energies $$E_\textrm{d}$$E d were in the range from $$79.76 \pm 8.77$$79.76 ± 8.77 kJ mol^-1 to $$162.85 \pm 32.23$$162.85 ± 32.23 kJ mol^-1. The present study is related to the starch hydrolysis by $${\alpha }$$α -amylase Bacillus spp. The obtained results might find application in the industry hydrolysis of starch.

Catalase is a potentially useful biocatalyst in various industrial bioprocesses (textile industry, food processing, and pulp and paper) that require removal of hydrogen peroxide. This process can be achieved in such reactors even under isothermal conditions. However, it is usually connected with a long duration of the process or with spending a considerable amount of biocatalyst for a unit mass of the transformed substrate, which in turn leads to an increase in operating costs. They can be limited by applying the optimal temperature control, which requires the values of the thermodynamic parameters -the activation energy for reaction and the activation energy for deactivation must be known. This work reports these parameters for hydrogen peroxide decomposition and Aspergillus niger catalase deactivation at temperatures ranging from 35ºC to 50ºC.

Catalase with the commercial catalase name Terminox Ultra is widely used in the textile industry in bleaching processes. This enzyme is used to catalyse the decomposition of residual hydrogen peroxide into oxygen and water. In this study catalase was kept for about 30 hours in water baths in a temperature range from 35 to 70°C. For the first time, the kinetics of thermal deactivation of this enzyme was examined using an oxygen electrode. Stability of the enzyme depends strongly on temperature and its half-life times are 0.0014 h and 7.6 h, at 35 and 70°C, respectively.

The present paper reports the determination of the activation energies and the optimum temperatures of starch hydrolysis by porcine pancreas α-amylase. The parameters were estimated based on the literature data on the activity curves versus temperature for starch hydrolysis by α-amylase from porcine pancreas. It was assumed that both the hydrolysis reaction process and the deactivation process of α-amylase were first-order reactions by the enzyme concentration. A mathematical model describing the effect of temperature on porcine pancreas α-amylase activity was used. The determine deactivation energies E_a were from 19.82 ± 7.22 kJ/mol to 128.80 ± 9.27 kJ/mol, the obtained optimum temperatures T_opt were in the range from 311.06 ± 1.10 K to 326.52 ± 1.75 K. In turn, the values of deactivation energies E_d has been noted in the range from 123.57 ± 14.17 kJ/mol to 209.37 ± 5.17 kJ/mol. The present study is related to the starch hydrolysis by α-amylase. In the industry, the obtained results the values E_a, E_d, T_opt can be used to design and optimize starch hydrolysis by α-amylase porcine pancreas. The obtained results might also find application in research on the pharmaceutical preparations used to treat pancreatic insufficiency or prognosis of pancreatic cancer.