Abstract
This research effort aimed at isolating and phenotypically characterizing lactic acid bacteria (LAB) isolates from a spontaneous rye sourdough manufactured following traditional protocols, as well as at evaluating their antimicrobial and antifungal properties as key features for future industrial applications. Thirteen LAB strains of potential industrial interest were isolated and identified to species-level via PCR. Most of the sourdough isolates showed versatile carbohydrate metabolisms. The Leuconostoc mesenteroides No. 242 and Lactobacillus brevis No. 173 demonstrated to be gas producers; thus, revealing their heterofermenter or facultative homofermenter features. Viable counts higher than 7.0 log10 (CFU/mL) were observed for Lactobacillus paracasei No. 244, Lactobacillus casei No. 210, L. brevis No. 173, Lactobacillus farraginis No. 206, Pediococcus pentosaceus No. 183, Lactobacillus uvarum No. 245 and Lactobacillus plantarum No. 135 strains, after exposure at pH 2.5 for 2 h. Moreover, L. plantarum No. 122, L. casei No. 210, Lactobacillus curvatus No. 51, L. paracasei No. 244, and L. coryniformins No. 71 showed growth inhibition properties against all the tested fifteen pathogenic strains. Finally, all LAB isolates showed antifungal activities against Aspergillus nidulans, Penicillium funiculosum, and Fusarium poae. These results unveiled the exceptionality of spontaneous sourdough as a source of LAB with effective potential to be considered in the design of novel commercial microbial single/mixed starter cultures, intended for application in a wide range of agri-food industries, where the antimicrobial and antifungal properties are often sought and necessary. In addition, metabolites therefrom may also be considered as important functional and bioactive compounds with high potential to be employed in food and feed, as well as cosmetic and pharmaceutical applications.
Highlights
Sourdough can be defined as an acidic sharp-tasting mixture of flour and water obtained after fermentation and used for the development of bread and other cereal-based products
It was published that Weissella cibaria and Lactobacillus sanfranciscensis were predominant in the microbiota of jiaozi and type I sourdoughs, respectively [44]
Chinese traditional sourdoughs from different regions were studied, and the results showed that the West group was significantly different from the North and South groups in the dominant genera [46]
Summary
Sourdough can be defined as an acidic sharp-tasting mixture of flour (or flours) and (salted) water obtained after fermentation and used for the development of bread and other cereal-based products. These fermented doughs are very complex biological ecosystems, where lactic acid bacteria (LAB) are dominant organisms, and mostly synergistically co-existing with yeasts; the latter are well adapted to the prevailing acidic environment and able to grow to high, but mainly lower concentrations than LAB [1,2,3,4]. LAB are generally accepted as safe microorganisms playing important roles in food fermentation and preservation, either by the presence of natural microbiota or through the addition of starter cultures (in single cultures or as consortia of multiple microbial species) under controlled conditions [11]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
