Understanding the Mechanisms of Positive Microbial Interactions That Benefit Lactic Acid Bacteria Co-cultures

Abstract

Microorganisms grow in concert, both in natural communities and in artificial or synthetic co-cultures. Positive interactions between associated microbes are paramount to achieve improved substrate conversion and process performance in biotransformation and fermented food production. The mechanisms underlying such positive interactions have been the focus of numerous studies in recent decades and are now starting to be well characterized. Lactic acid bacteria (LAB) contribute to the final organoleptic, nutritional, and health properties of fermented food products. However, interactions in LAB co-cultures have been little studied, apart from the well-characterized LAB co-culture used for yogurt manufacture. LAB are, however, multifunctional microorganisms that display considerable potential to create positive interactions between them. This review describes why LAB co-cultures are of such interest, particularly in foods, and how their extensive nutritional requirements can be used to favor positive interactions. In that respect, our review highlights the benefits of co-cultures in different areas of application, details the mechanisms underlying positive interactions and aims to show how mechanisms based on nutritional interactions can be exploited to create efficient LAB co-cultures.

Microbial association networks in cheese: a meta-analysis

“…Even if, ultimately, co-culturing in the laboratory and/or in appropriate model systems is the only way to obtain in-depth knowledge on the nature of interactions (Cosetta and Wolfe, 2019;D'Souza et al, 2018;Wolfe et al, 2014), the wealth of data provided by metataxonomic, metagenomic and metabolomics approaches provides ample opportunity to mine for microbial association networks and metabolic networks (Layeghifard et al, 2017;Liu et al, 2020;Röttjers and Faust, 2018). Microbial interactions in cheese and in other fermented foods have been the subject of recent comprehensive reviews (Blaya et al, 2017;Canon et al, 2020;Gobbetti et al, 2018;Mayo et al, 2021). A schematic, and possibly oversimplified representation of interactions (parasitism, commensalism, amensalism, competition, protocooperation) occurring in an idealized surface ripened cheese is shown in Figure 1, with some of the interactions described in detail in section 1.3 and Table 1.…”

“…Microbial interactions in cheese and in other fermented foods have been the subject of recent comprehensive reviews (Blaya et al, 2017; Canon et al, 2020; Gobbetti et al, 2018; Mayo et al, 2021). A schematic, and possibly oversimplified representation of interactions (parasitism, commensalism, amensalism, competition, protocooperation) occurring in an idealized surface ripened cheese is shown in Figure 1, with some of the interactions described in detail in section 1.3 and Table 1.…”

“…Surprisingly enough, to the best of our knowledge, approaches based on bipartite network analysis have not been recently used to elucidate the structure of PBINs of dairy LAB. The development of new high-throughput approaches for the study of the metavirome in dairy products (see Zotta et al, 2021 for a recent review) combined with network science approaches is certainly promising in studying the evolution of bacteriophage-host relationships in natural starters and cheese in self-assembled communities (Canon et al, 2020) in cheese manufacture, like the many cheeses produced by using undefined starters reproduced by back-slopping (Zotta et al, 2021), in which dispersal, diversification, evolution and drift (Nemergut et al, 2013) all play a role in shaping the structure, dynamics and function of the cheese microbial communities, at least in early stages of cheese-making. Finally, beyond their role in regulating the structure of bacterial populations, bacteriophages (and prophages) of LAB may have other beneficial effects in microbial communities (induction of lysis, with release on nutrients for other members of the community; providing mechanisms for recombination and gene exchange; Paillet and Dugat-Bon, 2021).…”

“…The networks structure of host microbiomes is known to be dramatically affected by disease (Layeghifard et al, 2017; Liu et al, 2020; Ma, 2018) and this has been proven to be true for mastitis (see Parente et al, 2020 for a review). Analysis of microbial association networks may help to mine for previously unknown interactions among bacteria relevant for cheese ripening and provide the basis for the design of microbiome based starter cultures (Canon et al, 2020; Mayo et al, 2021).…”

Protective Effect of Prunus mume Fermented with Mixed Lactic Acid Bacteria in Dextran Sodium Sulfate-Induced Colitis

“…Khan et al (2018) [ 19 ] reported that LAB-fermented dried longan contained higher phenolic and flavonoid contents and antioxidant capacities compared to unfermented dried longan. Pharmacological studies of LAB have been reported to convince the improvement of therapeutic effects, e.g., diarrhea, constipation and colitis [ 20 , 21 , 22 ]. Furthermore, LAB co-cultures could produce added value according to the increase in food quality, such as flavor and texture, and enhance functionality [ 23 ].…”