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

This study investigated the impact of Pediococcus pentosaceus 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 P. pentosaceus, were selected due to their low BA-producing and high BA-degrading ability for kisra fermentation. Inoculation with P. pentosaceus K-B21 or P. pentosaceus 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 P. pentosaceus 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.