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1.
Food Microbiol ; 61: 136-149, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27697163

RESUMEN

The present work demonstrates that yeasts belonging to the Schizosaccharomyces genus release a high quantity of polysaccharides of cell wall origin starting from the onset of the alcoholic fermentation. By the end of the alcoholic fermentation, all of the Schizosaccharomyces yeast strains released a quantity of polysaccharides approximately 3-7 times higher than that released by a commercial Saccharomyces cerevisiae yeast strain under the same fermentative conditions of synthetic juice. A higher content of polysaccharide was found in media fermented by Schizosaccharomyces japonicus with respect to that of Schizosaccharomyces pombe. Some of the strains evaluated were also able to produce high levels of pyruvic acid, which has been shown to be an important compound for color stability of wine. The presence of strains with different malic acid consumption patterns along with high polysaccharide release would enable production of naturally modified wines with enhanced mouth feel and reduced acidity. The chemical analysis of the released polysaccharides demonstrated divergence between the two yeast species S. pombe and S. japonicus. A different mannose/galactose ratio and a different percentage of proteins was observed on the polysaccharides released by S. pombe as compared to S. japonicus. Analysis of the proteins released in the media revealed the presence of a glycoprotein with a molecular size around 32-33 kDa only for the species S. japonicus. Mass spectrometry analysis of carbohydrate moieties showed similar proportions among the N-glycan chains released in the media by both yeast species but differences between the two species were also observed. These observations suggest a possible role of rapid MALDI-TOF screening of N-glycans compositional fingerprint as a taxonomic tool for this genus. Polysaccharides release in the media, in particular galactomannoproteins in significant amounts, could make these yeasts particularly interesting also for the industrial production of exogenous polysaccharide preparations.


Asunto(s)
Pared Celular/química , Polisacáridos/química , Polisacáridos/metabolismo , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Fermentación , Galactosa/análogos & derivados , Mananos/biosíntesis , Glicoproteínas de Membrana/biosíntesis , Polisacáridos/análisis , Polisacáridos/aislamiento & purificación , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/clasificación , Schizosaccharomyces/química , Schizosaccharomyces/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Vino/análisis , Vino/microbiología
2.
J Dairy Sci ; 99(10): 7733-7743, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27522435

RESUMEN

The composition of porcine milk oligosaccharides (PMO) was analyzed during early lactation and their relation to piglet gut microbiome was investigated. Pigs are considered ideal intestinal models to simulate humans because of the striking similarity in intestinal physiopathology to humans. The evolution of PMO was investigated in the milk from 3 healthy sows at prefarrowing, farrowing, and d 7 and 14 postpartum by Nano-LC Chip Quadrupole-Time-of-Flight mass spectrometer (Agilent Technologies, Santa Clara, CA). Previously sequenced metagenome libraries were reanalyzed to examine changes with specific gut bacterial populations. Over 30 oligosaccharides (OS) were identified in the milk, with 3'-sialyllactose, lacto-N-tetraose, α1-3,ß1-4-d-galactotriose, 2'-fucosyllactose, and 6'-sialyllactose being the most abundant species (accounting for ~70% of the total OS). Porcine milk had lower OS diversity (number of unique structures) than human milk, and appeared closer to bovine and caprine milk. In agreement with previous studies, only 3 fucosylated OS were identified. Surprisingly, their contribution to total OS abundance was greater than in bovine milk (9 vs. 1%). Indeed, fucosylated PMO increased during lactation, mirroring a similar trend observed for neutral and type I OS content during early lactation. Taken together, these results suggest that, in terms of abundance, PMO are closer to human milk than other domestic species, such as bovine and caprine milks. Metagenomic sequencing revealed that fucose-consuming bacterial taxa in the gut microbiota of piglets were qualitatively but not quantitatively different between nursing and weaning stages, suggesting that both the composition and structure of dietary glycans may play a critical role in shaping the distal gut microbiome. The similarity of both intestinal physiopathology and milk OS composition in human and porcine species suggests similar effects on gastrointestinal development of early nutrition, reinforcing the use of the pig intestinal model to simulate human intestinal models in the clinical setting.


Asunto(s)
Leche/química , Oligosacáridos/química , Porcinos , Animales , Bovinos , Heces/microbiología , Femenino , Cabras , Humanos , Lactancia
3.
Food Microbiol ; 43: 5-15, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24929876

RESUMEN

Eight non-Saccharomyces wine strains, previously selected for their ability to modulate the final concentrations of various volatile compounds and to persist with Saccharomyces cerevisiae in mixed inocula fermentations of grape juice, have been analyzed in the present work to test their ability to release mannoproteins. The eight strains were members of different genera originally isolated from grape: Hansensiaspora osmophila, Lachancea thermotolerans, Metschnikowia pulcherrima, Pichia fermentans, Saccharomycodes ludwigii, Starmerella bacillaris, Torulaspora delbrueckii and Zygosaccharomyces florentinus. A synthetic polysaccharide-free grape juice, was used to characterize the mannoproteins released during the alcoholic fermentation. Mannoproteins profiles were characterized by gel electrophoresis and carbohydrate composition was analyzed both by HPLC and by mass spectrometry. The eight non-Saccharomyces yeasts demonstrated a higher capacity to release polysaccharides compared to S. cerevisiae. The proteins released by the eight yeast strains showed a wide variety of protein sizes, ranging from 25 kDa to greater than 250 kDa. The mass spectrometric profile of the N-glycans ranged from 1600 to 4000 Da and was characteristic for each strain. Detailed investigation of the degree of polymerization of released N-glycans revealed variable composition from 8 to 15 units of monosaccharides.


Asunto(s)
Proteínas Fúngicas/biosíntesis , Glicoproteínas de Membrana/biosíntesis , Vino/microbiología , Levaduras/metabolismo , Fermentación , Proteínas Fúngicas/química , Glicoproteínas de Membrana/química , Peso Molecular , Vitis/metabolismo , Vitis/microbiología , Vino/análisis , Levaduras/química
4.
Small Rumin Res ; 113(2-3): 411-420, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24587592

RESUMEN

Milk oligosaccharides (OS)-free complex carbohydrates-confer unique health benefits to the nursing neonate. Though human digestive enzymes cannot degrade these sugars, they provide nourishment to specific commensal microbes and act as decoys to prevent the adhesion of pathogenic micro-organisms to gastrointestinal cells. At present, the limited quantities of human milk oligosaccharides (HMO) impede research on these molecules and their potential applications in functional food formulations. Considerable progress has been made in the study of OS structures; however, the synthetic pathways leading to their synthesis in the mammary gland are poorly understood. Recent studies show that complex OS with fucose and N-acetyl neuraminic acid (key structural elements of HMO bioactivity) exist in goat milk. Polymorphisms in the CSN1S1 locus, which is responsible for synthesis of αs1-casein, affect lipid and casein micelle structure in goat milk. The present study sought to determine whether CSN1S1 polymorphisms also influence goat milk oligosaccharide (GMO) production and secretion. The GMO compositions of thirty-two goat milk samples, half of which were from genotype A/A (αs1-casein producers) and half from genotype O/O (αs1-casein non-producers), were determined with nanoflow liquid chromatography high-accuracy mass spectrometry. This study represents the most exhaustive characterization of GMO to date. A systematic and comprehensive GMO library was created, consolidating information available in the literature with the new findings. Nearly 30 GMO, 11 of which were novel, were confirmed via tandem mass spectrometric analyses. Six fucosylated OS were identified; 4 of these matched HMO compositions and three were identified for the first time in goat milk. Importantly, multivariate statistical analysis demonstrated that the OS profiles of the A/A and O/O genotype milks could be discriminated by the fucosylated OS. Quantitative analysis revealed that the goat milk samples contained 1.17 g/L of OS; however, their concentration in milks from A/A and O/O genotypes was not different. This study provides evidence of a genetic influence on specific OS biosynthesis but not total OS production. The presence of fucosylated GMO suggests that goat milk represents a potential source of bioactive milk OS suitable as a functional food ingredient.

5.
J Dairy Sci ; 93(9): 3940-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20723667

RESUMEN

Oligosaccharides (OS) from bovine milk are a class of bioactive molecules that are receiving increasing commercial attention for their potential health benefits. In the present work we measured, comprehensively and systematically, free milk OS in the colostrum of 7 Holstein-Friesian cows during the first 3 d of lactation in 12-h intervals by HPLC-chip/time-of-flight mass spectrometry to determine the biological variation of free milk OS in early lactation. The high sensitivity and resolution of the analytical technique made it possible to monitor all OS species, thus providing a comprehensive and quantitative analysis of OS variations during colostrum production. This study confirmed that although sialyllactose is the major OS in bovine colostrum, several neutral OS species are present in significant abundance even at the third day of lactation. Furthermore, variation in terms of OS species and relative abundances of OS between cows suggest individual animal variation. These variations are likely due to genetic factors because environmental factors such as nutrition, lactation number, and accommodation were the same for all cows. This investigation revealed that colostrum milk from Holstein-Friesian cows is a rich source of neutral and acidic OS for the food and pharmaceutical industries.


Asunto(s)
Calostro/química , Lactancia/fisiología , Oligosacáridos/análisis , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Femenino , Lactancia/metabolismo , Lactosa/análogos & derivados , Espectrometría de Masas , Técnicas Analíticas Microfluídicas , Oligosacáridos/aislamiento & purificación , Ácidos Siálicos/análisis , Ácidos Siálicos/aislamiento & purificación
6.
Rev Med Liege ; 63(7-8): 474-9, 2008.
Artículo en Francés | MEDLINE | ID: mdl-18771225

RESUMEN

Ovarian hyperstimulation syndrome is the most severe iatrogenic complication of fertilization modern methods. This syndrome is characterized by a massive cystic ovarian enlargement associated with an acute body fluid shift. Ascite is the most frequent manifestation of this syndrome. In some rare cases ovarian hyperstimulation syndrome is complicated by massive unilateral pleural effusion without ascite. We describe the case of a 36 year old woman who developed a massive unilateral pleural effusion without ascite. An ovarian hyperstimulation syndrome was diagnosed. Chest tube drainage improved patient parameters and symptoms. We discuss the diagnostic approach of pleural effusions.


Asunto(s)
Síndrome de Hiperestimulación Ovárica/complicaciones , Derrame Pleural/etiología , Adulto , Ascitis/etiología , Tubos Torácicos , Drenaje , Femenino , Fertilización In Vitro/efectos adversos , Humanos , Síndrome de Hiperestimulación Ovárica/etiología , Derrame Pleural/diagnóstico , Derrame Pleural/cirugía
7.
J Chromatogr A ; 1428: 143-53, 2016 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-26427327

RESUMEN

A detailed qualitative and quantitative characterization of goat colostrum oligosaccharides (GCO) has been carried out for the first time. Defatted and deproteinized colostrum samples, previously treated by size exclusion chromatography (SEC) to remove lactose, were analyzed by nanoflow liquid chromatography-quadrupole-time of flight mass spectrometry (Nano-LC-Chip-Q-TOF MS). Up to 78 oligosaccharides containing hexose, hexosamine, fucose, N-acetylneuraminic acid or N-glycolylneuraminic acid monomeric units were identified in the samples, some of them detected for the first time in goat colostra. As a second step, a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS) methodology was developed for the separation and quantitation of the main GCO, both acidic and neutral carbohydrates. Among other experimental chromatographic conditions, mobile phase additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry of target carbohydrates. Narrow peaks (wh: 0.2-0.6min) and good symmetry (As: 0.8-1.4) were obtained for GCO using an acetonitrile:water gradient with 0.1% ammonium hydroxide at 40°C. These conditions were selected to quantify the main oligosaccharides in goat colostrum samples. Values ranging from 140 to 315mgL(-1) for neutral oligosaccharides and from 83 to 251mgL(-1) for acidic oligosaccharides were found. The combination of both techniques resulted to be useful to achieve a comprehensive characterization of GCO.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía Liquida , Calostro/química , Espectrometría de Masas , Oligosacáridos/química , Acetonitrilos/química , Hidróxido de Amonio/química , Animales , Técnicas de Química Analítica/instrumentación , Femenino , Cabras , Interacciones Hidrofóbicas e Hidrofílicas , Embarazo
9.
Radiol Med ; 96(1-2): 92-7, 1998.
Artículo en Italiano | MEDLINE | ID: mdl-9819625

RESUMEN

INTRODUCTION: Percutaneous treatment of chronic iliac artery occlusion has not yet gained complete acceptance as the method of choice. The reason of this widespread skepticism are the poor results achieved with angioplasty and/or lysis therapy. The introduction of stents seems to open new perspectives to percutaneous treatment and the latest follow-up studies report encouraging results. MATERIAL AND METHODS: We report our personal experience in percutaneous mechanical revascularization of chronic iliac occlusion with primary stent placement in 29 patients with 2 years' maximum follow-up. Clinically the patients had at least 3 months' claudication and were in Fontaine stages II to IV. The occlusion was passed mechanically using a hydrophilic guide wire, through the contralateral access in 19 cases and ipsilaterally in 10. The stents were primarily implanted in the last 12 patients; in the first 15 patients, after dilatation with undersized balloons, 25 Wallstent and 12 Palmaz stents were implanted. Each patient underwent color Doppler follow-up for 3-24 months. Nine patients underwent angiography too, after one year. RESULTS: The mechanical passage of the guide-wire through the occluded segment was successful in 27 of 29 (93.1%) patients referred for percutaneous revascularization of a chronic occlusion of the iliac artery. The stent was placed and immediate patency was achieved in 100% of these 27 patients. Clinical improvement was of two stages in 24 patients and of one stage in 3 patients. The follow-up showed neither reocclusions nor critical stenoses of the restored iliac segment. Five embolic complications (5%) occurred after angioplasty, all of them treated percutaneously; surgery was never necessary. DISCUSSION AND CONCLUSIONS: The follow-up studies published in the literature in the last few years and our personal experience encourage the percutaneous treatment of chronic iliac artery occlusions. Percutaneous mechanical revascularization with primary stent positioning can be proposed because it is a reliable and efficacious tool, particularly in young patients in whom a surgical aortoiliac or aortofemoral bypass might injure the pudendal plexis and cause sexual disturbances.


Asunto(s)
Arteriopatías Oclusivas/cirugía , Arteria Ilíaca , Stents , Adulto , Anciano , Arteriopatías Oclusivas/diagnóstico por imagen , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Radiología Intervencionista
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