Autism Spectrum Disorder (ASD) is a complex neurodevelopmental trouble characterized by deficits in communication and social interactions associated with restricted and repetitive behaviour, interests and activities. Given the heterogeneity of the disorder and the absence of biomarker, its diagnostic approach must be comprehensive and multidisciplinary, according to international classifications. The aetiology of ASDs remains mostly unknown and results from a multifactorial model.
View Article and Find Full Text PDFDespite recent advances in sequencing and culturing, a deep knowledge of the wiring and functioning of the human gut ecosystem and its microbiota as a community is still missing. A holistic mechanistic understanding will require study of the gut microbiota as an interactive and spatially organized biological system, which is difficult to do in complex natural communities. Synthetic gut microbial ecosystems can function as model systems to further current understanding of the composition, stability and functional activities of the microbiota.
View Article and Find Full Text PDFCurr Opin Pharmacol
December 2019
The use of and interest in probiotics to modulate the human intestinal microbiota have strongly increased in recent years. However, most of the current probiotic products have been limited to single-strain formulations of easily culturable food-grade microorganisms and often resulted in mixed results or limited effects on host health. Therefore, a revision of current probiotic strategies by using synthetic human-derived microbial multispecies consortia is necessary.
View Article and Find Full Text PDFBackground: In contrast to multiple rare monogenetic abnormalities, a common biomarker among children with infantile autism and their parents is the discovery of serum autoantibodies directed to the folate receptor alpha (FR) localized at blood-brain and placental barriers, impairing physiologic folate transfer to the brain and fetus. Since outcome after behavioral intervention remains poor, a trial was designed to treat folate receptor alpha (FR) autoimmunity combined with correction of deficient nutrients due to abnormal feeding habits.
Methods: All participants with nonsyndromic infantile autism underwent a routine protocol measuring CBC, iron, vitamins, coenzyme Q10, metals, and trace elements.
Key cocoa-specific aroma precursors are generated during the fermentation of cocoa beans via the proteolysis of the vicilin-like globulin. Previous studies had shown that degradation of this particular 566 amino acid-long storage protein leads to three distinct subunits with different molecular masses. Although oligopeptides generated from the proteolysis of vicilin-like globulin have been studied previously, changes occurring to vicilin at different stages of fermentation have not yet been explored in detail.
View Article and Find Full Text PDFMicrobial fermentation of the viscous pulp surrounding cocoa beans is a crucial step in chocolate production. During this process, the pulp is degraded, after which the beans are dried and shipped to factories for further processing. Despite its central role in chocolate production, pulp degradation, which is assumed to be a result of pectin breakdown, has not been thoroughly investigated.
View Article and Find Full Text PDFThe fermentation of cocoa beans is essential for the generation of flavour precursors that are required later on to form the flavour components of chocolate. From the many different precursors that are generated, oligopeptides and free amino acids comprise a significant proportion as some of them form Maillard reaction products during the roasting process. Therefore, the diversity of peptides is an important contributing factor to the quality of a fermentation which is in turn controlled by proteolytic activity within the cocoa bean, and is driven by changes in the presence of fermentation by-products as a result of microbial activity outside the bean.
View Article and Find Full Text PDFMicrobial starter cultures have extensively been used to enhance the consistency and efficiency of industrial fermentations. Despite the advantages of such controlled fermentations, the fermentation involved in the production of chocolate is still a spontaneous process that relies on the natural microbiota at cocoa farms. However, recent studies indicate that certain thermotolerant Saccharomyces cerevisiae cultures can be used as starter cultures for cocoa pulp fermentation.
View Article and Find Full Text PDFAppl Environ Microbiol
September 2015
Cocoa pulp fermentation is a spontaneous process during which the natural microbiota present at cocoa farms is allowed to ferment the pulp surrounding cocoa beans. Because such spontaneous fermentations are inconsistent and contribute to product variability, there is growing interest in a microbial starter culture that could be used to inoculate cocoa pulp fermentations. Previous studies have revealed that many different fungi are recovered from different batches of spontaneous cocoa pulp fermentations, whereas the variation in the prokaryotic microbiome is much more limited.
View Article and Find Full Text PDFFourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) is an ultra-high resolution mass spectrometry technique used mainly in analysis of unresolved complex mixtures comprising tens of thousands of analytes. For the first time, it was used to analyze samples of raw fermented cocoa beans originating from Cameroon and Ivory Coast. The direct infusion mass spectra of the raw fermented cocoa bean extracts showed 10091 and 10911 peaks, resp.
View Article and Find Full Text PDFThe fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region.
View Article and Find Full Text PDFAcetobacter pasteurianus, a Gram-negative bacterium belonging to the α-divison of Proteobacteria, produces acetic acid through ethanol oxidation. A genomic bank of A. pasteurianus 386B DNA was cloned in the low-copy cosmid pRG930Cm vector and the resulting clones were screened for the production of protease using the skimmed-milk agar assay whereby a clearing zone around the inoculated spots indicates casein degradation.
View Article and Find Full Text PDFCertain lactic acid bacteria, especially heterofermentative strains, are capable to produce mannitol under adequate culture conditions. In this study, mannitol production by Lactobacillus reuteri CRL 1101 and Lactobacillus fermentum CRL 573 in modified MRS medium containing a mixture of fructose and glucose in a 6.5:1.
View Article and Find Full Text PDFSpontaneous organic cocoa bean box fermentations were carried out on two different farms in Brazil. Physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (LAB) and acetic acid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. The main end-products of the catabolism of the pulp substrates (glucose, fructose, and citric acid) by yeasts, LAB, and AAB were ethanol, lactic acid, mannitol, and/or acetic acid.
View Article and Find Full Text PDFThe genome sequence of Lactobacillus sakei 23K has revealed that the species L. sakei harbors several genes involved in the catabolism of energy sources other than glucose in meat, such as glycerol, arginine, and nucleosides. In this study, a screening of 15 L.
View Article and Find Full Text PDFSourdough is a very competitive and challenging environment for microorganisms. Usually, a stable microbiota composed of lactic acid bacteria (LAB) and yeasts dominates this ecosystem. Although sourdough is rich in carbohydrates, thus providing an ideal environment for microorganisms to grow, its low pH presents a particular challenge.
View Article and Find Full Text PDFLactobacillus sakei is frequently present as the dominant lactic acid bacterium in spontaneously fermented meat products, demonstrating its competitiveness in and adaptation to the meat environment. Since meat is generally low in carbohydrate content, the ability to utilize other energy sources to generate ATP, such as arginine via the arginine deiminase (ADI) pathway, represents a competitive benefit. In this study, the kinetics of growth and arginine conversion capabilities of Lb.
View Article and Find Full Text PDFSourdough fermentation is a cereal fermentation that is characterized by the formation of stable yeast/lactic acid bacteria (LAB) associations. It is a unique process among food fermentations in that the LAB that mostly dominate these fermentations are heterofermentative. In the present study, four wheat sourdough fermentations were carried out under different conditions of temperature and backslopping time to determine their effect on the composition of the microbiota of the final sourdoughs.
View Article and Find Full Text PDFLactic acid bacteria (LAB) are of industrial importance in the production of fermented foods, including sourdough-derived products. Despite their limited metabolic capacity, LAB contribute considerably to important characteristics of fermented foods, such as extended shelf-life, microbial safety, improved texture, and enhanced organoleptic properties. Triggered by the considerable amount of LAB genomic information that became available during the last decade, transcriptome and, by extension, metatranscriptome studies have become one of the most appropriate research approaches to study whole-ecosystem gene expression in more detail.
View Article and Find Full Text PDFWe previously found that Wickerhamomyces anomalus (formerly Hansenula anomala, Pichia anomala) was the second most frequently isolated yeast in Belgian artisan bakery sourdoughs and that the yeast dominated laboratory sourdough fermentations. Such findings are of interest in terms of the advantage of W. anomalus over other commonly encountered sourdough yeasts and its potential introduction into the sourdough ecosystem.
View Article and Find Full Text PDFCocoa bean fermentation is a spontaneous process involving a succession of microbial activities, starting with yeasts, followed by lactic acid bacteria and acetic acid bacteria. So far, all microbiological studies about cocoa bean fermentation were based on culture-dependent (isolation, cultivation, and identification), or, more recently, culture-independent (PCR-DGGE, or polymerase chain reaction denaturing gradient gel electrophoresis) methods. Using a metagenomic approach, total DNA was extracted from heap and box fermentations at different time points and from different locations (Ghana and Brazil, respectively) to generate a 16 S rDNA clone library that was sequenced.
View Article and Find Full Text PDFSourdough fermentations are characterized by the combined activity of lactic acid bacteria and yeasts. An investigation of the microbial composition of 21 artisan sourdoughs from 11 different Belgian bakeries yielded 127 yeast isolates. Also, 12 spontaneous 10-day laboratory sourdough fermentations with daily backslopping were performed with rye, wheat, and spelt flour, resulting in the isolation of 217 yeast colonies.
View Article and Find Full Text PDFThe arginine deiminase (ADI) pathway is a means by which certain sourdough lactic acid bacteria (LAB) convert arginine into ornithine via citrulline while producing ammonia and ATP, thereby coping with acid stress and gaining an energetic advantage. Lactobacillus fermentum IMDO 130101, an isolate from a spontaneous laboratory rye sourdough, possesses an ADI pathway which is modulated by environmental pH. In the present study, a broader view of the activity of the ADI pathway in response to growth under two other commonly encountered stress factors, temperature and added salt, was obtained.
View Article and Find Full Text PDFSourdough is a microbial ecosystem of lactic acid bacteria (LAB) and yeasts in a matrix of mainly cereal flour and water. Culture-dependent and culture-independent microbiological analysis together with metabolite target analyses of different sourdoughs enabled to understand this complex fermentation process. It is difficult to link the species diversity of the sourdough microbiota with the (geographical) type of sourdough and the flour used, although the type and quality of the latter is the main source of autochthonous LAB in spontaneous sourdough fermentations and plays a key role in establishing stable microbial consortia within a short time.
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