## 4 Discussion  
By running the process under the most favourable conditions, it is possible to obtain lactic acid (LA) as the main product with the highest efficiency of 96%, and further running the process affects the gradual decrease in LA in fermented plant extracts. The study of the influence of technological parameters on the fermentation process of clove buds shows that favourable results are obtained by conducting fermentation in the presence of \(L\). _Hammosus_ strain MI-0272, using an initial sugar content of 3.20% (in terms of the amount of molasses of 40.32 g), a plant material content of 6.40% (64.50 g), and a time of 10 days (Tables S1-S3). The fermentation process of buds produces a fermented plant extract (FPE) with the highest antioxidant activity (AA) of 33.90 mmol Tx/L \(\pm\) 0.04 and the highest content of phenolic compounds (TPC) of 11.60 mmol GA/L \(\pm\) 0.04. Lactic acid bacteria are microorganisms of industrial importance that are known for their fermentation abilities, mainly due to their probiotic benefits as well as their production of lactic acid. When fermentation is carried out, LA production is inhibited, and a gradual decrease in the growth rate of lactic acid bacteria cells is observed [39]. Consequently, a gradual decrease in lactic acid concentration is observed as the process is prolonged. Lactic acid inhibition is caused by the ability of undissociated lactic acid to dissolve in the cytoplasmic membrane, while dissociated lactate remains insoluble. This leads to acidification of the cytoplasm and disruption of proton motive forces. This event affects the pH gradient across the cell membrane and reduces the cellular energy available for growth (Tables 1 and 2). Polyphenic glucosides contained in clove buds are converted into more bioactive compounds (anthocyanin glucosides to their aglycone forms and free phenolic acids), thus leading to a higher content of phenolic compounds in fermented plant extracts. In addition, the simpler structure of the derived metabolites contributes to the higher antioxidant activity of FPEs, with an increase in their ability to reduce DPPH radicals relative to non-fermented extracts [40; 41; 42]. Optimisation of technological parameters on the fermentation of clove buds in the presence of \(L\). _Hammosus_ MI-0272 showed that the highest values of the tested functions (AA, TPC, and LA\({}_{\text{e}}\)) were obtained on day 9 of the process, using a plant material content of 6.40% and an initial sugar content of 3.20%. This yields a fermented plant extract characterised by high antioxidant activity (AA) and a high content of polyphenic compounds (TPC). Increasing the content of the plant material (above 3.20%) hinders the hydrolysis of the 6-carbon sugars, with the result that incomplete hydrolysis of the sugars is observed [43]. This significantly reduces the efficiency of LA formation during fermentation. Using an optimal initial sugar concentration of 3.20%, lactic acid is obtained with a maximum efficiency of 96% (Tables 3 and 5; Figures 1 and 2). Lactic acid efficiency values first increased during the process, then reached a maximum on day 9 or 10 of fermentation (depending on the strain used). Continuing the fermentation process resulted in a decrease in the efficiency of the lactic acid formed. When conducting fermentation, inhibiting LA production often occurs, and a gradual decrease in the growth rate of lactic acid bacteria cells is observed. Therefore, a gradual decrease in lactic acid concentration is observed as the process continues. The inhibition of lactic acid is caused by the ability of the undissociated lactic acid to dissolve in the cytoplasmic membrane, while the dissociated lactate remains insoluble. This leads to acidification of the cytoplasm and the disruption of proton motive forces. This event impacts the pH gradient across the cell membrane and reduces the cellular energy available for growth [42]. Comparing the influences of the type of strain used on the efficiency of the LA obtained, it was found that the use of \(L\).