Influence of Pediococcus pentosaceus Starter Cultures on Biogenic Amine Content and Antioxidant Activity in African Sourdough Flatbread Fermentation

This study investigated the impact of <i>Pediococcus pentosaceus</i> strains not only on biogenic amine (BA) content, but also on antioxidant indices, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and total phenolic content, in kisra, an African sourdough flatbread. Among forty-six lactic acid bacteria (LAB) strains isolated from naturally fermented kisra sourdough, two strains (K-B21, K-B01) identified as <i>P. pentosaceus,</i> were selected due to their low BA-producing and high BA-degrading ability for kisra fermentation. Inoculation with <i>P. pentosaceus</i> K-B21 or <i>P. pentosaceus</i> K-B01 completely prevented the formation of tyramine and cadaverine during kisra fermentation. The levels of putrescine, histamine, spermine, and spermidine in kisra were reduced by about 90%, >31%, 55-61%, and 9-25%, respectively, by the two strains, compared to the control (natural fermentation). Additionally, DPPH scavenging activity was 83-84% in the control and inoculated groups of kisra. The total phenolic content was 1977.60 μg/g in the control and insignificantly lower in the inoculated groups (1850-1880 μg/g) than the control. These results suggest that <i>P. pentosaceus</i> K-B21 and K-B01 are promising candidates for use as sourdough starter cultures to produce kisra bread of higher quality, including both its safety and health functionality.