## 3 Results and Discussion
### Lactic Acid Content and Microbial Profiles of Silages  
This isolate showed significant antimicrobial, antioxidant with sufficient probioticic characteristics, next, we investigated the efficacy of this isolate on acidification of silage and lactic acid production corn and fortail millet forages. In the current study, we used corn and fortail millet forages at the ratio of 1:1 for silage production by ensiling process (Table 3). However, limited populations of LAB have been found in natural plants, it is not sufficient to induce expected fermentation of silages results favoring undesirable microbial growth. Hence, the addition of LAB is essential for silage production. In the current study, we used _L. salivarius_ as an inoculant for corn and fortail millet silage production by the ensiled method. The lower number of LAB was noted in the control silage (5.3 \(\pm\) 0.29 Log CFU/g). In contrast, the higher LAB population was noted in silage inoculated with AS22 (6.8 \(\pm\) 0.14 Log CFU/g), indicating that the addition of AS22 competes for the epiphytic communities present in the plants. In addition, fungi and actinomycetes population were recorded in AS22 inoculated silage compared to control silage; it suggested that the AS22 had the ability to inhibit the spores of fungi (1.2 \(\pm\) 0.36 vs. 0.9 \(\pm\) 0.29) and actinomycetes (0.72 \(\pm\) 0.28 vs. 0.43 \(\pm\) 0.19 Log CFU/g) present in the natural plants compared to non-inoculated silages. Modification of the microbial population during this phase in successfully fermented silages indicated the disappearance of entero-bacteria. These changes are closely associated with lowering pH and higher lactic acid production in LAB inoculated silages [52]. Similarly, in the current study, we noted lower pH level  
Figure 5: DPPH scavenging properties of _L. salivarius_ AS22 at various concentrations. The cell-free extract was assayed at various concentrations and the scavenging effect was determined.  
(5.29 \(\pm\) 0.03 vs. 3.84 \(\pm\) 0.07 Log CFU/g) and higher lactic acid production (22.3 \(\pm\) 3.9 vs. 38.7 \(\pm\) 1.4 \(\mathrm{\SIUnitSymbolMicro g}\)/g) in silage inoculated with AS22 compared to the control. Many researches have confirmed the efficacy of _L. salivarius_ on the fermentation of silages produced from various plants. Most of the studies suggested the use of _L. salivarius_ as an additive during silage production to enhance silage quality via increasing essential organic acids, particularly lactic acid which lowers pH and inhibits unwanted microbial growth [53; 54]. Previously published data significantly correlated with our present experimental results, here we found the addition of _L. salivarius_ strongly reduced pH and increased lactic acid content than non-inoculated silages, and this condition could preserve the silage for a long time. In general, an increase in acidification is closely associated with the preservation of silages and it reduces proteolytic enzyme-mediated degradation and controls the growth of the enterobacteria and clostridia [55]. The pH is generally used to monitor the silage quality and the pH range between 3.8 and 4.2 is considered a benchmark for well-preserved silage [56]. Lactic acid is a key acid present higher level in the fermented silages and it reduces the pH of the silages during fermentation, approximately 10-20 times higher than the other acids [56]. Similarly, more LAB population, higher lactic acid and lower pH range were noted in silage inoculated with AS22 compared to control. These are the major factors to enhance fermentation quality and prevent undesirable microbial growth such as enterobacteria, fungi and actinomycetes.