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•Plant fermentation is like a metabolic labyrinth undertaken by bacteria.•Omics approaches unraveled the metabolic traits of bacteria to adapt to plants.•Most of the winding metabolic ...pathways involve phenolic compounds.•Fermented plant foods are enriched with high bioavailable bioactive compounds.•Fermentation of plant matrices result in low amounts of anti-nutritional factors.
Even though lactic acid bacteria are only a small part of the plant autochthonous microbiota, they represent the most important microbes having the capability to promote significant changes in the health-promoting properties of plant foods. Owing to the variety of plant chemical components and the possible pathways for bioconversion, plant fermentation is like a metabolic labyrinth undertaken by bacteria. The winding metabolic pathways involve several secondary plant metabolites (e.g. phenolics). The success of these paths is connected to the adaptive growth and survival of lactic acid bacteria. A panel of various interacting omics approaches unraveled the specific traits of lactic acid bacteria to adapt to plants, which allow the optimal design of fermentation strategies for targeted raw matrices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The complex polymicrobial composition of human gut microbiota plays a key role in health and disease. Lachnospiraceae belong to the core of gut microbiota, colonizing the intestinal lumen from birth ...and increasing, in terms of species richness and their relative abundances during the host's life. Although, members of Lachnospiraceae are among the main producers of short-chain fatty acids, different taxa of Lachnospiraceae are also associated with different intra- and extraintestinal diseases. Their impact on the host physiology is often inconsistent across different studies. Here, we discuss changes in Lachnospiraceae abundances according to health and disease. With the aim of harnessing Lachnospiraceae to promote human health, we also analyze how nutrients from the host diet can influence their growth and how their metabolites can, in turn, influence host physiology.
Lactic acid fermentation represents the easiest and the most suitable way for increasing the daily consumption of fresh-like vegetables and fruits. Literature data are accumulating, and this review ...aims at describing the main features of the lactic acid bacteria to be used for fermentation. Lactic acid bacteria are a small part of the autochthonous microbiota of vegetables and fruits. The diversity of the microbiota markedly depends on the intrinsic and extrinsic parameters of the plant matrix. Notwithstanding the reliable value of the spontaneous fermentation to stabilize and preserve raw vegetables and fruits, a number of factors are in favour of using selected starters. Two main options may be pursued for the controlled lactic acid fermentation of vegetables and fruits: the use of commercial/allochthonous and the use of autochthonous starters. Several evidences were described in favour of the use of selected autochthonous starters, which are tailored for the specific plant matrix. Pro-technological, sensory and nutritional criteria for selecting starters were reported as well as several functional properties, which were recently ascribed to autochthonous lactic acid bacteria. The main features of the protocols used for the manufacture of traditional, emerging and innovative fermented vegetables and fruits were reviewed. Tailored lactic acid bacteria starters completely exploit the potential of vegetables and fruits, which enhances the hygiene, sensory, nutritional and shelf life properties.
► Exploitation of vegetables and fruits through lactic acid fermentation. ► Criteria for selecting starters include technological and functional properties. ► The advantages of using autochthonous starters were described. ► Emerging and traditional fermented vegetable and fruit products were also reviewed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Sourdough fermentation is one of the oldest food biotechnologies, which has been studied and recently rediscovered for its effect on the sensory, structural, nutritional and shelf life properties of ...leavened baked goods. Acidification, proteolysis and activation of a number of enzymes as well as the synthesis of microbial metabolites cause several changes during sourdough fermentation, which affect the dough and baked good matrix, and influence the nutritional/functional quality. Currently, the literature is particularly rich of results, which show how the sourdough fermentation may affect the functional features of leavened baked goods. In the form of pre-treating raw materials, fermentation through sourdough may stabilize or to increase the functional value of bran fractions and wheat germ. Sourdough fermentation may decrease the glycaemic response of baked goods, improve the properties and bioavailability of dietary fibre complex and phytochemicals, and may increase the uptake of minerals. Microbial metabolism during sourdough fermentation may also produce new nutritionally active compounds, such as peptides and amino acid derivatives (e.g., γ-amino butyric acid) with various functionalities, and potentially prebiotic exo-polysaccharides. The wheat flour digested via fungal proteases and selected sourdough lactobacilli has been demonstrated to be probably safe for celiac patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Stress Physiology of Lactic Acid Bacteria Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A ...
Microbiology and molecular biology reviews,
09/2016, Volume:
80, Issue:
3
Journal Article
Peer reviewed
Open access
Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the ...technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance.
The quality of some leavened, sourdough baked goods is not always consistent, unless a well propagated sourdough starter culture is used for the dough fermentation. Among the different types of ...sourdough used, the traditional sourdough has attracted the interest of researchers, mainly because of its large microbial diversity, especially with respect to lactic acid bacteria. Variation in this diversity and the factors that cause it will impact on quality and is the subject of this review.
Sourdough microbial diversity is mainly caused by the following factors: (i) sourdough is obtained through spontaneous, multi-step fermentation; (ii) it is propagated using flour, whose nutrient content may vary according to the batch and to the crop, and which is naturally contaminated by microorganisms; and (iii) it is propagated under peculiar technological parameters, which vary depending on the historical and cultural background and type of baked good. In the population dynamics leading from flour to mature sourdough, lactic acid bacteria (several species of Lactobacillus sp., Leuconostoc sp., and Weissella sp.) and yeasts (mainly Saccharomyces cerevisiae and Candida sp.) outcompete other microbial groups contaminating flour, and interact with each other at different levels. Ecological parameters qualitatively and quantitatively affecting the dominant sourdough microbiota may be classified into specific technological parameters (e.g., percentage of sourdough used as inoculum, time and temperature of fermentation) and parameters that are not fully controlled by those who manage the propagation of sourdough (e.g., chemical, enzyme and microbial composition of flour).
Although some sourdoughs have been reported to harbour a persistent dominant microbiota, the stability of sourdough ecosystem during time is debated. Indeed, several factors may interfere with the persistence of species and strains associations that are typical of a given sourdough: metabolic adaptability to the stressing conditions of sourdough, nutritional and antagonistic interactions among microorganisms, intrinsic robustness of microorganisms, and existence of a stable house microbiota.
Further studies have to be performed in order to highlight hidden mechanisms underlying the microbial structure and stability of sourdough. The comprehension of such mechanisms would be helpful to assess the most appropriate conditions that allow keeping a given traditional sourdough as a stable microbial ecosystem, thus preserving, during time, the typical traits of the resulting product.
•Lactic acid bacteria and yeasts dominate traditional sourdoughs.•Different specific technological parameters lead to sourdough microbial diversity.•Microbial stability is not ensured by application of constant technology parameters.•Flour and house microbiota affect microbial stability of traditional sourdough.•Succession of microorganisms causes variations of sourdough performances over time.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
PURPOSE OF REVIEWThe spread of the Western lifestyle across the globe has led to a pandemic in obesity-related metabolic disease. The Mediterranean diet (MedDiet), Okinawa diet (OkD) and Nordic diet, ...derived from very different regions of the world and culinary traditions, have a large whole plant food component and are associated with reduced disease risk. This review focuses on polyphenol : microbiome interactions as one possible common mechanistic driver linking the protective effects whole plant foods against metabolic disease across healthy dietary patterns irrespective of geography.
RECENT FINDINGSAlthough mechanistic evidence in humans is still scarce, animal studies suggest that polyphenol or polyphenol rich foods induce changes within the gut microbiota and its metabolic output of trimethylamine N-oxide, short-chain fatty acids, bile acids and small phenolic acids. These cross-kingdom signaling molecules regulate mammalian lipid and glucose homeostasis, inflammation and energy storage or thermogenesis, physiological processes determining obesity-related metabolic and cardiovascular disease risk. However, it appears that where in the intestine metabolites are produced, the microbiota communities involved, and interactions between the metabolites themselves, can all influence physiological responses, highlighting the need for a greater understanding of the kinetics and site of production of microbial metabolites within the gut.
SUMMARYInteractions between polyphenols and metabolites produced by the gut microbiota are emerging as a possible unifying protective mechanism underpinning diverse healthy dietary patterns signaling across culinary traditions, across geography and across domains of life.
This study aimed at investigating the fecal microbiota and metabolome of children with Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) and autism (AD) in comparison to healthy ...children (HC). Bacterial tag-encoded FLX-titanium amplicon pyrosequencing (bTEFAP) of the 16S rDNA and 16S rRNA analyses were carried out to determine total bacteria (16S rDNA) and metabolically active bacteria (16S rRNA), respectively. The main bacterial phyla (Firmicutes, Bacteroidetes, Fusobacteria and Verrucomicrobia) significantly (P<0.05) changed among the three groups of children. As estimated by rarefaction, Chao and Shannon diversity index, the highest microbial diversity was found in AD children. Based on 16S-rRNA and culture-dependent data, Faecalibacterium and Ruminococcus were present at the highest level in fecal samples of PDD-NOS and HC children. Caloramator, Sarcina and Clostridium genera were the highest in AD children. Compared to HC, the composition of Lachnospiraceae family also differed in PDD-NOS and, especially, AD children. Except for Eubacterium siraeum, the lowest level of Eubacteriaceae was found on fecal samples of AD children. The level of Bacteroidetes genera and some Alistipes and Akkermansia species were almost the highest in PDD-NOS or AD children as well as almost all the identified Sutterellaceae and Enterobacteriaceae were the highest in AD. Compared to HC children, Bifidobacterium species decreased in AD. As shown by Canonical Discriminant Analysis of Principal Coordinates, the levels of free amino acids and volatile organic compounds of fecal samples were markedly affected in PDD-NOS and, especially, AD children. If the gut microbiota differences among AD and PDD-NOS and HC children are one of the concomitant causes or the consequence of autism, they may have implications regarding specific diagnostic test, and/or for treatment and prevention.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study aimed at investigating the addition of legume (chickpea, lentil and bean) flours to wheat flour bread. Type I sourdough containing legumes or wheat–legume flours were prepared and ...propagated (back slopped) in laboratory, according to traditional protocols that are routinely used for making typical Italian breads. Based on kinetic of acidification and culture-dependent data, the wheat–legume sourdough was further characterized and selected for bread making. As determined by RAPD-PCR and partial sequencing of 16S rDNA gene analyses, lactic acid bacteria in wheat–legume sourdough included Lactobacillus plantarum, Lactobacillus sanfranciscensis, Leuconostoc mesenteroides, Lactobacillus fermentum, Weissella cibaria, Lactobacillus pentosus, Lactobacillus coryneformis, Lactobacillus rossiae, Lactobacillus brevis, Lactobacillus parabuchneri and Lactobacillus paraplantarum. Two breads containing 15% (w/w) of legume (chickpea, lentil and bean) flours were produced using selected wheat–legume sourdough (WLSB) and traditional wheat sourdough (WSB). Compared to wheat yeasted bread (WYB), the level of total free amino acids (FAA) was higher in WSB and WLSB. Phytase and antioxidant activities were the highest in WLSB. Compared to bread WYB, the addition of legume flours decreased the in vitro protein digestibility (IVPD) (WYB versus WSB). However, the dough fermentation with WSLB favored an increase of IVPD. According to the levels of carbohydrates, dietary fibers and resistant starch, WSB and WLSB showed lower values of hydrolysis index (HI) compared to WYB. As showed by texture and image analyses and sensory evaluation of breads, a good acceptability was found for WSB and, especially, WLSB breads.
•A protocol for sourdough fermentation of a mixture of wheat and legume flours was set up.•The lactic acid bacteria microbiota of wheat–legume sourdough was characterized.•Legume and sourdough fermentation increased functional compounds of wheat bread.•Wheat–legume sourdough increased phytase and antioxidant activities of wheat bread.•Wheat–legume sourdough decreased the hydrolysis index of wheat bread.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK