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1.
Crit Rev Biotechnol ; 44(6): 1080-1102, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39103281

RESUMEN

The rapid increase in the worldwide prevalence of obesity and certain non-communicable diseases (NCDs), such as: cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes, has been mainly attributed to an excess of sugar consumption. Although the potential benefits of the synergetic use of sweeteners have been known for many years, recent development based on synthesis strategies to produce sucrose-like taste profiles is emerging where biocatalyst approaches may be preferred to produce and supply specific sweetener compounds. From a nutritional standpoint, high-intensity sweeteners have fewer calories than sugars while providing a major sweet potency, placing them in the spotlight as valuable alternatives to sugar. Due to the modern world awareness and incidence of metabolic diseases, both food research and growing markets have focused on two generally regarded as safe (GRAS) groups of compounds: the sweet diterpenoid glycosides present on the leaves of Stevia rebaudiana and, more recently, on the cucurbitane triterpene glycosides present on the fruits of Siraitia grosvenorii. In spite of their flavor advantages, biological benefits, including: antidiabetic, anticancer, and cardiovascular properties, have been elucidated. The present bibliographical review dips into the state-of-the-art of sweeteners and their role in human health as sugar replacements, as well as the biotransformation methods for steviol gylcosides and mogrosides apropos of enzymatic technology to update and locate the discoveries to date in the scientific literature to help boost the continuity of research efforts of the ongoing sweeteners.


Asunto(s)
Stevia , Edulcorantes , Humanos , Cucurbitaceae/metabolismo
2.
Carbohydr Polym ; 342: 122399, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048235

RESUMEN

This work demonstrates that sesame (Sesamum indicum L.) hull, an unexploited food industrial waste, can be used as an efficient source for the extraction of hemicellulose and/or pectin polysaccharides to further obtain functional oligosaccharides. Different polysaccharides extraction methods were surveyed including alkaline and several enzymatic treatments. Based on the enzymatic release of xylose, arabinose, glucose, and galacturonic acid from sesame hull by using different enzymes, Celluclast®1.5 L, Pectinex®Ultra SP-L, and a combination of them were selected for the enzymatic extraction of polysaccharides at 50 °C, pH 5 up to 24 h. Once the polysaccharides were extracted, Ultraflo®L was selected to produce arabinoxylo-oligosaccharides (AXOS) at 40 °C up to 24 h. Apart from oligosaccharides production from extracted polysaccharides, alternative approaches for obtaining oligosaccharides were also explored. These were based on the analysis of the supernatants resulting from the polysaccharide extraction, alongside a sequential hydrolysis performed with Celluclast®1.5 L and Ultraflo®L of the starting raw sesame hull. The different fractions obtained were comprehensively characterized by determining low molecular weight carbohydrates and monomeric compositions, average Mw and dispersity, and oligosaccharide structure by MALDI-TOF-MS. The results indicated that sesame hull can be a useful source for polysaccharides extraction (pectin and hemicellulose) and derived oligosaccharides, especially AXOS.


Asunto(s)
Oligosacáridos , Sesamum , Sesamum/química , Oligosacáridos/química , Hidrólisis , Polisacáridos/química , Xilanos/química , Xilanos/aislamiento & purificación , Pectinas/química , Pectinas/aislamiento & purificación , Residuos Industriales , Arabinosa/química , Xilosa/química
3.
Microb Biotechnol ; 17(5): e14443, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38722820

RESUMEN

Pectin structures have received increasing attention as emergent prebiotics due to their capacity to promote beneficial intestinal bacteria. Yet the collective activity of gut bacterial communities to cooperatively metabolize structural variants of this substrate remains largely unknown. Herein, the characterization of a pectin methylesterase, BpeM, from Bifidobacterium longum subsp. longum, is reported. The purified enzyme was able to remove methyl groups from highly methoxylated apple pectin, and the mathematical modelling of its activity enabled to tightly control the reaction conditions to achieve predefined final degrees of methyl-esterification in the resultant pectin. Demethylated pectin, generated by BpeM, exhibited differential fermentation patterns by gut microbial communities in in vitro mixed faecal cultures, promoting a stronger increase of bacterial genera associated with beneficial effects including Lactobacillus, Bifidobacterium and Collinsella. Our findings demonstrate that controlled pectin demethylation by the action of a B. longum esterase selectively modifies its prebiotic fermentation pattern, producing substrates that promote targeted bacterial groups more efficiently. This opens new possibilities to exploit biotechnological applications of enzymes from gut commensals to programme prebiotic properties.


Asunto(s)
Hidrolasas de Éster Carboxílico , Heces , Malus , Pectinas , Prebióticos , Malus/microbiología , Pectinas/metabolismo , Heces/microbiología , Hidrolasas de Éster Carboxílico/metabolismo , Hidrolasas de Éster Carboxílico/genética , Fermentación , Humanos , Bifidobacterium longum/metabolismo , Bifidobacterium longum/enzimología , Microbioma Gastrointestinal , Bifidobacterium/enzimología , Bifidobacterium/metabolismo
4.
Food Chem Toxicol ; 187: 114638, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582341

RESUMEN

With a society increasingly demanding alternative protein food sources, new strategies for evaluating protein safety issues, such as allergenic potential, are needed. Large-scale and systemic studies on allergenic proteins are hindered by the limited and non-harmonized clinical information available for these substances in dedicated databases. A missing key information is that representing the symptomatology of the allergens, especially given in terms of standard vocabularies, that would allow connecting with other biomedical resources to carry out different studies related to human health. In this work, we have generated the first resource with a comprehensive annotation of allergens' symptomatology, using a text-mining approach that extracts significant co-mentions between these entities from the scientific literature (PubMed, ∼36 million abstracts). The method identifies statistically significant co-mentions between the textual descriptions of the two types of entities in the literature as indication of relationship. 1,180 clinical signs extracted from the Human Phenotype Ontology, the Medical Subject Heading terms of PubMed together with other allergen-specific symptoms, were linked to 1,036 unique allergens annotated in two main allergen-related public databases via 14,009 relationships. This novel resource, publicly available through an interactive web interface, could serve as a starting point for future manually curated compilation of allergen symptomatology.


Asunto(s)
Alérgenos , Minería de Datos , Humanos , Minería de Datos/métodos , Bases de Datos Factuales , Proteínas/metabolismo
5.
Molecules ; 29(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38257197

RESUMEN

Peptide-protein interactions form a cornerstone in molecular biology, governing cellular signaling, structure, and enzymatic activities in living organisms. Improving computational models and experimental techniques to describe and predict these interactions remains an ongoing area of research. Here, we present a computational method for peptide-protein interactions' description and prediction based on leveraged amino acid frequencies within specific binding cores. Utilizing normalized frequencies, we construct quantitative matrices (QMs), termed 'logo models' derived from sequence logos. The method was developed to predict peptide binding to HLA-DQ2.5 and HLA-DQ8.1 proteins associated with susceptibility to celiac disease. The models were validated by more than 17,000 peptides demonstrating their efficacy in discriminating between binding and non-binding peptides. The logo method could be applied to diverse peptide-protein interactions, offering a versatile tool for predictive analysis in molecular binding studies.


Asunto(s)
Enfermedad Celíaca , Péptidos , Humanos , Aminoácidos , Biología Molecular , Posición Específica de Matrices de Puntuación
6.
J Agric Food Chem ; 71(28): 10693-10700, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37409693

RESUMEN

Intestinal lactic acid bacteria can help alleviate lactose maldigestion by promoting lactose hydrolysis in the small intestine. This study shows that protein extracts from probiotic bacterium Lactiplantibacillus plantarum WCFS1 possess two metabolic pathways for lactose metabolism, involving ß-galactosidase (ß-gal) and 6Pß-galactosidase (6Pß-gal) activities. As L. plantarum WCFS1 genome lacks a putative 6Pß-gal gene, the 11 GH1 family proteins, in which their 6Pß-glucosidase (6Pß-glc) activity was experimentally demonstrated,, were assayed for 6Pß-gal activity. Among them, only Lp_3525 (Pbg9) also exhibited a high 6Pß-gal activity. The sequence comparison of this dual 6Pß-gal/6Pß-glc GH1 protein to previously described dual GH1 proteins revealed that L. plantarum WCFS1 Lp_3525 belonged to a new group of dual 6Pß-gal/6Pß-glc GH1 proteins, as it possessed conserved residues and structural motifs mainly present in 6Pß-glc GH1 proteins. Finally, Lp_3525 exhibited, under intestinal conditions, an adequate 6Pß-gal activity with possible relevance for lactose maldigestion management.


Asunto(s)
Lactobacillus plantarum , Probióticos , Galactosidasas/metabolismo , Glucosidasas/metabolismo , Lactosa/metabolismo , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo , Metabolismo de los Hidratos de Carbono , Bacterias/metabolismo , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo
7.
Microorganisms ; 11(6)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37374967

RESUMEN

Considering the ban on the use of antibiotics as growth stimulators in the livestock industry, the use of microbiota modulators appears to be an alternative solution to improve animal performance. This review aims to describe the effect of different families of modulators on the gastrointestinal microbiota of poultry, pigs and ruminants and their consequences on host physiology. To this end, 65, 32 and 4 controlled trials or systematic reviews were selected from PubMed for poultry, pigs and ruminants, respectively. Microorganisms and their derivatives were the most studied modulator family in poultry, while in pigs, the micronutrient family was the most investigated. With only four controlled trials selected for ruminants, it was difficult to conclude on the modulators of interest for this species. For some modulators, most studies showed a beneficial effect on both the phenotype and the microbiota. This was the case for probiotics and plants in poultry and minerals and probiotics in pigs. These modulators seem to be a good way for improving animal performance.

8.
Genes (Basel) ; 14(4)2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37107700

RESUMEN

Scientific knowledge is being accumulated in the biomedical literature at an unprecedented pace. The most widely used database with biomedicine-related article abstracts, PubMed, currently contains more than 36 million entries. Users performing searches in this database for a subject of interest face thousands of entries (articles) that are difficult to process manually. In this work, we present an interactive tool for automatically digesting large sets of PubMed articles: PMIDigest (PubMed IDs digester). The system allows for classification/sorting of articles according to different criteria, including the type of article and different citation-related figures. It also calculates the distribution of MeSH (medical subject headings) terms for categories of interest, providing in a picture of the themes addressed in the set. These MeSH terms are highlighted in the article abstracts in different colors depending on the category. An interactive representation of the interarticle citation network is also presented in order to easily locate article "clusters" related to particular subjects, as well as their corresponding "hub" articles. In addition to PubMed articles, the system can also process a set of Scopus or Web of Science entries. In summary, with this system, the user can have a "bird's eye view" of a large set of articles and their main thematic tendencies and obtain additional information not evident in a plain list of abstracts.


Asunto(s)
Bibliometría , Humanos , PubMed , Bases de Datos Factuales
9.
J Agric Food Chem ; 70(49): 15531-15538, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36454042

RESUMEN

The hydrolysis of plant glucosinolates by myrosinases (thioglucosidases) originates metabolites with chemopreventive properties. In this study, the ability to hydrolyze the glucosinolate sinigrin by cultures or protein extracts of Lactiplantibacillus plantarum WCFS1 was assayed. This strain possesses myrosinase-like activity as sinigrin was partly hydrolyzed by induced cultures but not by protein extracts. The 11 glycoside hydrolase GH1 family proteins, annotated as 6-phospho-ß-glucosidases, were the proteins most similar to plant myrosinases. The activity of these proteins was assayed against sinigrin and synthetic glucosides. As expected, none of the proteins assayed possessed myrosinase activity against sinigrin or the synthetic ß-thio-glucoside derivative or against the ß-glucoside. However, all 11 proteins were active on the phosphorylated-ß-glucoside derivative. Moreover, only eight of these proteins were active on phospho-ß-thioglucose. These results supported that, in L. plantarum WCFS1, glucosinolates may undergo previous phosphorylation, and GH1 proteins are the glycosidases involved in the hydrolysis of phosphorylated glucosinolates.


Asunto(s)
Glucosinolatos , Glicósido Hidrolasas , Glucosinolatos/metabolismo , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Hidrólisis
10.
J Agric Food Chem ; 70(29): 9048-9056, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35830712

RESUMEN

This study was conducted to investigate the sweetness intensity and the potential fecal microbiome modulation of galactooligosaccharides in combination with enzymatically modified mogrosides (mMV-GOS), both generated through a patented single-pot synthesis. Sweetness intensity was performed in vivo by trained sensory panelists. The impact on the human fecal microbiome was evaluated by in vitro pH-controlled batch fermentation, and bacterial populations and organic acid concentrations were measured by qPCR and GC-FID, respectively. Significant growth (p ≤ 0.05) during the fermentation at 10 h of bacterial populations includes Bifidobacterium (8.49 ± 0.44 CFU/mL), Bacteroides (9.73 ± 0.32 CFU/mL), Enterococcus (8.17 ± 0.42 CFU/mL), and Clostridium coccoides (6.15 ± 0.11 CFU/mL) as compared to the negative control counts for each bacterial group (7.94 ± 0.27, 7.84 ± 1.11, 7.52 ± 0.37, and 5.81 ± 0.08 CFU/mL, respectively) at the same time of fermentation. Likewise, the corresponding significant increase in production of SCFA in mMV-GOS at 10 h of fermentation, mainly seen in acetate (20.32 ± 2.56 mM) and propionate (9.49 ± 1.44 mM) production compared to a negative control at the same time (8.15 ± 1.97 and 1.86 ± 0.24 mM), is in line with a positive control (short-chain fructooligosaccharides; 46.74 ± 12.13 and 6.51 ± 1.91 mM, respectively) revealing a selective fermentation. In conclusion, these substrates could be considered as novel candidate prebiotic sweeteners, foreseeing a feasible and innovative approach targeting the sucrose content reduction in food. This new ingredient could provide health benefits when evaluated in human studies by combining sweetness and prebiotic fiber functionality.


Asunto(s)
Ácidos Grasos Volátiles , Prebióticos , Bacterias/genética , Bifidobacterium , Heces/microbiología , Fermentación , Humanos , Oligosacáridos , Edulcorantes
11.
Benef Microbes ; 13(2): 95-168, 2022 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-35729770

RESUMEN

Together with proteins and fats, carbohydrates are one of the macronutrients in the human diet. Digestible carbohydrates, such as starch, starch-based products, sucrose, lactose, glucose and some sugar alcohols and unusual (and fairly rare) α-linked glucans, directly provide us with energy while other carbohydrates including high molecular weight polysaccharides, mainly from plant cell walls, provide us with dietary fibre. Carbohydrates which are efficiently digested in the small intestine are not available in appreciable quantities to act as substrates for gut bacteria. Some oligo- and polysaccharides, many of which are also dietary fibres, are resistant to digestion in the small intestines and enter the colon where they provide substrates for the complex bacterial ecosystem that resides there. This review will focus on these non-digestible carbohydrates (NDC) and examine their impact on the gut microbiota and their physiological impact. Of particular focus will be the potential of non-digestible carbohydrates to act as prebiotics, but the review will also evaluate direct effects of NDC on human cells and systems.


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Bacterias/metabolismo , Carbohidratos de la Dieta/metabolismo , Fibras de la Dieta/metabolismo , Ecosistema , Humanos , Polisacáridos/metabolismo , Almidón/metabolismo
12.
Front Microbiol ; 12: 750635, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34777303

RESUMEN

In the current study the ability of four previously characterized bifidobacterial ß-galactosidases (designated here as BgaA, BgaC, BgaD, and BgaE) to produce galacto-oligosaccharides (GOS) was optimized. Of these enzymes, BgaA and BgaE were found to be promising candidates for GOS production (and the corresponding GOS mixtures were called GOS-A and GOS-E, respectively) with a GOS concentration of 19.0 and 40.3% (of the initial lactose), respectively. GOS-A and GOS-E were partially purified and structurally characterized. NMR analysis revealed that the predominant (non-lactose) disaccharide was allo-lactose in both purified GOS preparations. The predominant trisaccharide in GOS-A and GOS-E was shown to be 3'-galactosyllactose, with lower levels of 6'-galactosyllactose and 4'-galactosyllactose. These three oligosaccharides have also been reported to occur in human milk. Purified GOS-A and GOS-E were shown to be able to support bifidobacterial growth similar to a commercially available GOS. In addition, GOS-E and the commercially available GOS were shown to be capable of reducing Escherichia coli adhesion to a C2BBe1 cell line. Both in vitro bifidogenic activity and reduced E. coli adhesion support the prebiotic potential of GOS-E and GOS-A.

13.
Int J Biol Macromol ; 193(Pt B): 1093-1102, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34780892

RESUMEN

This work addresses the amino acid sequence, structural analysis, biochemical characterization and glycosidase activity of two recombinant α-rhamnosidases, Ram1 and Ram2, from Lactobacillus plantarum WCFS1. The substrate specificity of both enzymes towards the disaccharide rutinose and natural dietary flavonoids naringin and rutin was also determined and compared to that of a commercial multienzyme complex (Pectinex Ultra Passover, PPO). Ram1 is a less acidic- and heat-active enzyme than Ram2 and exhibited a high activity towards pNP-α-L-rhamnopyranoside, but it was unable to hydrolyze neither rutinose, naringin or rutin. In contrast, Ram2 enzyme showed a substrate specificity towards α-(1➔6) glycosidic flavonoids, such as rutin, and the disaccharide rutinose. The mechanism of action of Ram2 towards rutin was elucidated and revealed the potential cost-effective and selective production of the monoglycosylated flavonoid isoquercetin (quercetin-3-O-glucoside). PPO efficiently converted both naringin and rutin into their corresponding aglycones. These findings revealed the potential usefulness of PPO for the improvement of sensory properties of beverages through debittering of citrus juices, as well as the potential use of Ram2 to selectively produce isoquercetin, a highly valued and bioactive flavonoid whose production is not currently affordable.


Asunto(s)
Proteínas Bacterianas , Flavanonas/química , Glicósido Hidrolasas , Lactobacillus plantarum/enzimología , Rutina/química , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Glicósido Hidrolasas/biosíntesis , Glicósido Hidrolasas/química , Glicósido Hidrolasas/aislamiento & purificación
14.
Food Chem Toxicol ; 157: 112584, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34582965

RESUMEN

A ranking of gluten T-cell epitopes triggering celiac disease (CD) for its potential application in the safety assessment of innovative food proteins is developed. This ranking takes into account clinical relevance and information derived from key steps involved in the CD pathogenic pathway: enzymatic digestion, epitope binding to HLA-DQ receptors of the antigen-presenting cells and activation of pro-inflammatory CD4 T-cells, which recognizes the HLA-DQ-epitope complex and initiates the inflammatory response. In silico chymotrypsin digestion was the most discriminatory tool for the ranking of gluten T-cell epitopes among all digestive enzymes studied, classifying 81% and 60% of epitopes binding HLA-DQ2.5 and HLA-DQ8 molecules, respectively, with a high risk. A positive relationship between the number of prolines and the risk of gluten T-cell epitopes was identified. HLA-binding data analysis revealed the additional role played by the flanking regions of the 9-mer epitopes whereas the integration of T-cell activation data into the ranking strategy was incomplete because it was difficult to combine results from different studies. The overall ranking proposed in decreasing order of immunological relevance was: α-gliadins > ω-gliadins > hordeins > γ-gliadins âˆ¼ avenins âˆ¼ secalins > glutenins. This novel approach can be considered as a first step to reshape the risk assessment strategy of innovative proteins and their potential to trigger CD.


Asunto(s)
Enfermedad Celíaca/inmunología , Alimentos/efectos adversos , Epítopos Inmunodominantes/clasificación , Enfermedad Celíaca/etiología , Epítopos , Epítopos de Linfocito T/inmunología , Glútenes/efectos adversos , Glútenes/inmunología , Antígenos HLA-DQ/inmunología , Humanos , Medición de Riesgo
15.
Vet Res ; 52(1): 99, 2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34215335

RESUMEN

The immunomodulatory capacity of F. hepatica antigens is probably one of the main reasons for the development of a driven non-protective Th2 immune response. In this study, we analysed the cellular response of hepatic lymph node cells and CD4+ T cells in terms of proliferative response, efficiency of antigen presentation and cytokine production, to F. hepatica-derived molecules, at early and late stages of the infection. Thirty-one sheep were allocated into five groups and were slaughtered at 16 dpi and 23 wpi. In order to analyse antigen-specific response, the following F. hepatica recombinant molecules were used: rFhCL1, rFhCL2, rFhCL3, rFhCB1, rFhCB2, rFhCB3, rFhStf-1, rFhStf-2, rFhStf-3 and rFhKT1. A cell proliferation assay using hepatic lymph node cells and an antigen presentation cell assay using CD4+ T cells were performed. At 16 dpi, all molecules but rFhStf-2 and rFhKT1 elicited a significant cell proliferative response on hepatic lymph node cells of infected animals. At both early and late stage of the infection, antigen presentation of rFhCB3 and rFhCL2 resulted in higher stimulation index of CD4+ T cells which was IL-2 mediated, although no statistically significant when compared to uninfected animals. Significant cytokine production (IL-4, IL-10 and IFN-γ) was conditioned by the antigen-specific cell stimulation. No CD4+ T cell exhaustion was detected in infected sheep at the chronic stage of the infection. This study addressed antigen-specific response to F. hepatica-derived molecules that are involved in key aspects of the parasite survival within the host.


Asunto(s)
Antígenos Helmínticos/inmunología , Fascioliasis/veterinaria , Ganglios Linfáticos/inmunología , Enfermedades de las Ovejas/inmunología , Linfocitos T/inmunología , Animales , Fasciola hepatica/fisiología , Fascioliasis/inmunología , Fascioliasis/parasitología , Hígado/inmunología , Masculino , Ovinos , Enfermedades de las Ovejas/parasitología , Oveja Doméstica
16.
Carbohydr Polym ; 264: 117980, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33910710

RESUMEN

Comprehensive chemical characterization of nine mono-varietal apple pomaces obtained from the production of ciders with PDO is described. They were rich in essential minerals, fibers (35-52.9 %), and polyphenols. High levels in GalA (11.8-21.6 %), revealed the suitability of these apple pomaces as efficient sources of pectins. Extracted pectins showed high variability in monomer composition, with degrees of methylesterification, strongly associated with pectins functional properties, ranging from 58 to 88 %. For a subset of apple pomace varieties, pectin extraction was accomplished by conventional acid heat treatment or ultrasound. Despite ultrasound-assisted extraction did not improve pectin yield, it minimized levels of "non-pectin" components as revealed by the low content of Glc/Man, leading to the obtainment of high-purity pectin. Our work highlights the key role played by the selection of the apple variety to streamline the potential food applications (gelling/thickening agents or prebiotics) of the extracted pectins that largely depend on their structural features.

17.
J Agric Food Chem ; 69(3): 955-965, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33434031

RESUMEN

This work describes the high capacity of MelA α-galactosidase from Lactobacillus plantarum WCFS1 to transfer galactosyl residues from melibiose to the C6-hydroxyl group of disaccharide-acceptors with ß-linkages (lactulose, lactose, and cellobiose) or α-linkages (isomaltulose and isomaltose) to produce novel galactose-containing hetero-oligosaccharides (HOS). A comprehensive nuclear magnetic resonance characterization of the transfer products derived from melibiose:lactulose reaction mixtures revealed the biosynthesis of α-d-galactopyranosyl-(1 → 6)-ß-d-galactopyranosyl-(1 → 4)-ß-d-fructose as the main component as well as the presence of α-d-galactopyranosyl-(1 → 3)-ß-d-galactopyranosyl-(1 → 4)-ß-d-fructose and α-d-galactopyranosyl-(1 → 6)-α-d-galactopyranosyl-(1 → 6)-ß-d-galactopyranosyl-(1 → 4)-ß-d-fructose. Melibiose-derived α-galactooligosaccharides (α-GOS), manninotriose and verbascotetraose, were also simultaneously synthesized. An in vitro assessment of the intestinal digestibility of the novel biosynthesized HOS revealed a high resistance of α-galactosides derived from lactulose, lactose, cellobiose, and isomaltulose. According to the evidence gathered for conventional α-GOS and certain disaccharides used as acceptors in this work, these novel nondigestible α-galactosides could be potential candidates to selectively modulate the gut microbiota composition, among other applications, such as low-calorie food ingredients.


Asunto(s)
Proteínas Bacterianas/metabolismo , Galactosa/metabolismo , Lactobacillus plantarum/metabolismo , Oligosacáridos/biosíntesis , alfa-Galactosidasa/metabolismo , Proteínas Bacterianas/genética , Galactosa/análisis , Lactobacillus plantarum/enzimología , Lactobacillus plantarum/genética , Lactulosa/metabolismo , Oligosacáridos/química , alfa-Galactosidasa/genética
18.
J Agric Food Chem ; 69(3): 1011-1019, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33428404

RESUMEN

Luo Han Guo fruit extract (Siraitia grosvenorii), mainly composed of mogroside V (50%), could be considered a suitable alternative to free sugars; however, its commercial applications are limited by its unpleasant off-notes. In the present work, a central composite design method was employed to optimize the transglycosylation of a mogroside extract using cyclodextrin glucosyltransferases (CGTases) from three different bacteriological sources (Paenibacillus macerans, Geobacillus sp., and Thermoanaerobacter sp.) considering various experimental parameters such as maltodextrin and mogroside concentration, temperature, time of reaction, enzymatic activity, and pH. Product structures were determined by liquid chromatography coupled to a diode-array detector (LC-DAD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Sensory analysis of glucosylated mogrosides showed an improvement in flavor attributes relevant to licorice flavor and aftereffect. Consequently, an optimum methodology was developed to produce new modified mogrosides more suitable when formulating food products as free sugar substitutes.


Asunto(s)
Proteínas Bacterianas/química , Cucurbitaceae/química , Glucósidos/biosíntesis , Glucosiltransferasas/química , Extractos Vegetales/química , Edulcorantes/síntesis química , Biocatálisis , Cromatografía Líquida de Alta Presión , Frutas/química , Geobacillus/enzimología , Glucósidos/química , Paenibacillus/enzimología , Extractos Vegetales/síntesis química , Espectrometría de Masa por Ionización de Electrospray , Edulcorantes/química , Thermoanaerobacter/enzimología
19.
Food Res Int ; 139: 109940, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33509494

RESUMEN

In order to know the catalytic activities of the disaccharidases expressed in the mammalian small intestinal brush-border membrane vesicles (BBMV) high concentrated solutions of sucrose, maltose, isomaltulose, trehalose and the mixture sucrose:lactose were incubated with pig small intestine disaccharidases. The hydrolysis and transglycosylation reactions generated new di- and trisaccharides, characterized and quantified by GC-MS and NMR, except for trehalose where only hydrolysis was detected. In general, α-glucosyl-glucoses and α-glucosyl-fructoses were the most abundant structures, whereas no fructosyl-fructoses or fructosyl-glucoses were found. The in-depth structural characterization of the obtained carbohydrates represents a new alternative to understand the potential catalytic activities of pig small intestinal disaccharidases. The hypothesis that the oligosaccharides synthesized by glycoside hydrolases could be also hydrolysed by the same enzymes was confirmed. This information could be extremely useful in the design of new non-digestible or partially digestible oligosaccharides with potential prebiotic properties.


Asunto(s)
Glicósido Hidrolasas , Intestino Delgado , Animales , Hidrólisis , Microvellosidades , Oligosacáridos , Porcinos
20.
Crit Rev Food Sci Nutr ; 61(19): 3267-3278, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32744076

RESUMEN

Oro-gastrointestinal digestion of dietary carbohydrates involves up to six different carbohydrases in a multistage process. Enzymes from the small intestinal brush border membrane play a major role in the digestibility of these substrates. However, to date, the inclusion of these small intestinal enzymes has been dismissed in most in vitro studies carried out, despite their importance in the degradation of carbohydrates. Several in vitro and in vivo studies have demonstrated the capability of brush border enzymes to degrade certain "non-digestible" carbohydrates to a different extent depending on their structural composition (monomeric composition, glycosidic linkage, etc.). In this sense, considering the available evidence, mucosal disaccharidases embedded in the small intestinal brush border membrane vesicles must be considered in addition to α-amylases; therefore, new approaches for the evaluation of the digestibility of carbohydrates have been recently reported. These new methods based on the utilization of the small intestinal enzymes present in the brush border membrane aim to fulfill the final and key step of the digestion of carbohydrates in the small intestine. Here, rat small intestinal extract enzymes as well as brush border membrane vesicles from pig have emerged as very reliable and useful tools to evaluate carbohydrate digestion. Thus, this review aims to go briefly through the most relevant digestion methods for carbohydrates that are currently available and to highlight the new improved methods, which include mammalian intestinal enzymes, and their current use in the evaluation of the digestibility of prebiotics.


Asunto(s)
Digestión , Prebióticos , Animales , Carbohidratos de la Dieta , Intestino Delgado , Microvellosidades , Ratas , Porcinos
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