Absorción mineral y retención ósea en ratas normales en crecimiento por el consumo de un yogur experimental reducido en lactosa que contiene galactooligosacáridos (GOS) / Mineral absorption and bone retention in normal growing rats by consumption of an experimental lactose-reduced yogurt containing galactooligosaccharides (GOS)

Introducción: Los GOS son prebióticos naturales presentes en la leche materna que pue-den obtenerse enzimáticamente a partir de la lactosa de leche de vaca durante la fabricación de yogur. El producto lácteo resultante será reducido en lactosa y contendrá prebióticos y bacterias potencialmente probióticas. Sin embargo, mantendrá la baja relación Ca/Pi que aporta la leche de vaca, lo que podría alterar el remodelamiento óseo y la mineralización. Objetivo: comparar si un yogur reducido en lactosa que contiene GOS (YE) ofrece ventajas adicionales respecto de un yogur regular sin GOS (YR) sobre las absorciones (Abs) de Ca y Pi, retención y calidad ósea durante el crecimiento normal. Al destete, ratas machos fueron divididas en 3 grupos alimentados con AIN ́93-G (C), YE o YR durante 28 días. Resultados: YE mostró el mayor aumento de lactobacilos fecales; producción de ácidos grasos de cadena corta especialmente p, profundidad de las criptas colónicas y menor pH cecal. El %AbsCa y %AbsPi aumentó en el siguiente órden: YE> YR> C (p < 0,05). El contenido de Ca y Pi en fémur, la densidad y contenido mineral óseos y los parámetros biomecánicos fueron similares en YE y C, mientras que YR mostró valores significativa-mente menores (p < 0,05). Conclusiones: YE aumentó las Abs y biodisponibilidad de minerales, alcanzando la retención y calidad ósea de C. El aumento en las Abs observado en YR no logró obtener la retención y calidad ósea de C. Conclusión: YE habría contrarrestado el efecto negativo del mayor aporte de Pi de la leche de vaca y sería una buena estrategia para lograr el pico de masa ósea y calidad del hueso adecuados, especialmente en individuos intolerantes a la lactosa. (AU)

Breast milk contains an optimal calcium/phosphate (Ca/Pi) ratio and GOS. These natural prebiotics can be enzymatically produced via cow's milk lactose inyogurt manufacture. This milk product is low in lactose and contains prebiotics and potentially probiotic bacteria but maintains a low Ca/Pi ratio that could alter bone remodeling and mineralization. We evaluated if a lactose-reduced yogurt containing GOS (YE) offers additional advantages over regular yogurt without GOS (YR) on Ca and Pi absorption (Abs), bone retention and quality during normal growth. Weaning male rats were divided into 3 groups fed AIN'93-G (C), YE or YR for 28 days. Results: YE showed the highest increase in fecal lactobacilli; short-chain fatty acids production, especially propionate and butyrate; intestine crypt depth, and the lowest cecal pH. AbsCa% and AbsPi% increased in this order: YE> YR> C (p <0.05). Ca and Pi content in femur, bone density and mineral content, and biomechanical parameters were similar in YE and C, while YR showed the significantly lowest value (p < 0.05). Conclusions: YE increased mineral Abs reaching the retention and bone quality of C. Although YR increased Abs, bone retention and quality did not achieve C values. Seemingly, YE compensated for the negative effect of the higher Pi supply and would be a good strategy to achieve adequate peak bone mass and bone quality, especially in lactose intolerant individuals. (AU)

Synthesis of b(1 ? 3) and b(1 ? 6) galactooligosaccharides from lactose and whey using a recombinant b-galactosidase from Pantoea anthophila

BACKGROUND: Milk whey, a byproduct of the dairy industry has a negative environmental impact, can be used as a raw material for added-value compounds such as galactooligosaccharides (GOS) synthesis by bgalactosidases. RESULTS: B-gal42 from Pantoea anthophila strain isolated from tejuino belonging to the glycosyl hydrolase family GH42, was overexpressed in Escherichia coli and used for GOS synthesis from lactose or milk whey. Crude cell-free enzyme extracts exhibited high stability; they were employed for GOS synthesis reactions. In reactions with 400 g/L lactose, the maximum GOS yield was 40% (w/w) measured by HPAEC-PAD, corresponding to 86% of conversion. This enzyme had a strong predilection to form GOS with b(1 ? 6) and b (1 ? 3) galactosyl linkages. Comparing GOS synthesis between milk whey and pure lactose, both of them at 300 g/L, these two substrates gave rise to a yield of 38% (60% of lactose conversion) with the same product profile determined by HPAEC-PAD. CONCLUSIONS: B-gal42 can be used on whey (a cheap lactose source) to produce added value products such as galactooligosaccharides.

Effects of a GOS+FOS supplemented formula on stool characteristics and fecal beneficial bacteria content in infants / 临床儿科杂志

Objective To investigate the impact of an infant formula supplemented with 1.34 g/L oligosaccharides mixture (galactooligosaccharides and fructooligosaccharides,GOS+FOS) on growth,stool characteristics and fecal beneficial bacteria content in healthy infants.Methods 25 formula-fed (FF) infants and 29 breast-fed (BF) infants within 3 weeks after birth were included and followed up.FF infants were exclusively fed with GOS+FOS supplemented formula at the median age of 13d (1-27d).Body weight and head circumference at 6 and 12 weeks were measured.The frequency,consistency,and color of the infant's stool,and occurrences of spit-up or vomiting during the study period were recorded daily by the parents.Stool samples were collected at 6 and 12 weeks of age,and then subjected to quantitative real-time polymerase chain reaction assays for the enumeration of lactobacillus,bifidobacteria,Bifidobacterium longum,Bifidobacterium breve and Bifidobacterium adolescentis.Results No difference in daily weight gain was detected between the two groups (33.56 ± 7.03g vs.31.18 + 6.91g,P=0.22)during the observation phase from 6 to 12 weeks.FF infants had less frequent and firmer stools at 6 weeks than BF infants,and they both had similar stool frequency,color and consistency at the end of study.FF infants had less fecal Bifidobacterium,B.longum and B.breve at 6 weeks,but those differences became less significant at 12 weeks with more increase in fecal B.longum and B.breve levels in FF infants during the follow up.Conclusions The GOS+FOS supplemented formula provides adequate nutrition for growth,and promotes soft stools and intestinal bifidogenic effects in healthy infants.

Production of extracellular α-galactosidase by Bacillus sp. LX-1 in solid state fermentation for application as a potential feed additive / Producción de α-galactosidasa por Bacillus sp. LX-1 en fermentación en estado sólido para su aplicación como potencial aditivo alimenticio / Produção de α-galactosidase por Bacillus sp. LX-1 em fermentação em estado sólido para o uso como um potencial aditivo na alimentação

Background: α-galacto-oligosaccharides, including raffinose and stachyose, are present in soybean meal and used widely as a protein source in poultry diets. These compounds have anti-nutritive effects that ultimately reduce performance and value of birds. Thus, the addition of exogenous α-galactosidase to poultry diets -which can initiate the digestion of these non-digestible sugars- can be an effective strategy to solve the nutritional disorders associated with consumption of these oligosacharides. Solid state fermentation (SSF) has drawn attention for the production of microbial enzymes, due to the possibility of using cheap and abundant agro-industrial residues as substrates. Objective: to present information on α-galactosidase production under SSF conditions by an Antarctic bacterial isolate, Bacillus LX-1. Methods: initially, wheat bran, soybean meal, corn flour and the combinations of these individual substrates with nutritive supplements containing 1% galactose, 0.5% yeast extract, 1% tryptone, and 0.001% MnSO(4)4H2O were evaluated to select an optimal medium in SSF to produce extracellular α-galactosidase. Certain fermentation parameters involving incubation time, moisture content, and initial pH were investigated separately. Additional studies were conducted to evaluate the influence on enzyme production of different carbon sources (glucose, sucrose, galactose, lactose, and maltose) and nitrogen sources (peptone, tryptone, sodium nitrate and ammonium sulfate). Results: a medium containing soybean meal resulted in best α-galactosidase synthesis and was used for further SSF explorations with Bacillus sp. LX-1. Maximum enzyme production was observed at a growth period of 72 h, 75% moisture content and pH 8.0. Enzyme activity was enhanced in the presence of galactose or lactose as the carbon source, and tryptone or peptone as the nitrogen source. Conclusion: this SSF technique could be potentially used to produce α-galactosidase for poultry feed.

Antecedentes: los α-galacto-oligosacáridos, incluyendo rafinosa y estaquiosa, están presentes en la harina de soja, la cual es utilizada ampliamente como fuente de proteína en dietas de aves. Estos compuestos tienen efectos anti-nutricionales que reducen el rendimiento de las aves. La adición de α-galactosidasa exógena a dietas de aves puede iniciar la digestión de esos azúcares, resultando en una estrategia eficaz para resolver los desórdenes nutricionales asociados con el consumo de dichos oligosacáridos. La fermentación en estado sólido (SSF) se puede usar para producir enzimas microbianas, debido a la posibilidad de utilizar residuos agroindustriales abundantes y baratos como sustrato. Objetivo: informar sobre la producción de α-galactosidasas por una bacteria antártica (Bacillus LX-1) bajo condiciones de SSF. Métodos: se evaluaron salvado de trigo, harina de soja, harina de maíz y las combinaciones individuales de estos sustratos con suplementos nutritivos conteniendo 1% de galactosa, 0,5% de extracto de levadura, 1% de triptona y 0,001% de MnSO(4)4H2O para seleccionar un medio óptimo de SSF para producir α-galactosidasa extracelular. Ciertos parámetros de fermentación incluyendo tiempo de incubación, contenido de humedad, y pH inicial se evaluaron por separado. Se realizaron estudios adicionales para evaluar la influencia de diferentes fuentes de carbono (glucosa, sucrosa, galactosa, lactosa y maltosa) y de nitrógeno (peptona, triptona, nitrato de sodio y sulfato de amonio) sobre la producción enzimatica. Resultados: un medio con harina de soja resultó ser el mejor para la síntesis de α-galactosidasa y se utilizó para nuevas exploraciones de SSF con Bacillus sp. LX-1. La producción máxima de la enzima se observó en un periodo de crecimiento de 72 h, a 75% de humedad y pH 8,0. La actividad enzimática mejoró en presencia de galactosa o lactosa como fuente de carbono, y triptona o peptona como fuente de nitrógeno. Conclusión: la técnica de SSF podría ser utilizada para producir α-galactosidasa destinada a la alimentación de aves de corral.

Antecedentes: os α-galacto-oligossacarídeos, incluindo rafinose e estaquiose, estão presentes na farinha de soja, que é amplamente utilizado como uma fonte de proteína em dietas de aves domésticas. Estes compostos têm efeitos anti-nutricionais que reduzem o desempenho das aves. A adição de α-galactosidase exógena em dietas de aves pode começar a digerir estes açúcares, resultando em uma estratégia eficaz para resolver os problemas nutricionais associados com o consumo desses oligossacarídeos. A fermentação em estado sólido (SSF) pode ser usada para produzir enzimas microbianas, devido à possibilidade de utilização de resíduos agroindustriais como substrato abundante e barato. Objetivo: relatar a produção de α-galactosidase por uma bactéria da Antártida (Bacillus LX- 1) em SSF. Métodos: foram avaliados o farelo de trigo, farelo de soja, farelo de milho e combinações específicas destes substratos com suplementos nutricionais contendo 1% de galactose, 0,5% de extrato de levedura, 1% de triptona e 0,001% de MnSO(4)4H2O para selecionar um meio ideal de SSF para produzir extracelular α-galactosidase. Certos parâmetros de fermentação, incluindo tempo de incubação, teor de umidade e pH inicial foram avaliados separadamente. Estudos adicionais foram conduzidos para avaliar a influência de diferentes fontes de carbono (glucose, sacarose, galactose, lactose e maltose) e de azoto (peptona, triptona, nitrato de sódio e sulfato de amónio) na produção da enzima. Resultados: um meio com farelo de soja acabou por ser o melhor para a síntese de α-galactosidase e foi usado para uma maior exploração de SSF com Bacillus sp. LX - 1. A produção máxima da enzima foi observada em um período de crescimento de 72 h, 75% de humidade e pH 8,0. Melhoria da atividade enzimática na presença de galactose ou lactose como fonte de carbono e de triptona e peptona como fonte de azoto. Conclusão: A técnica da SSF poderia ser usada para produzir α-galactosidase para a alimentação de aves domésticas.

Effect of prebiotics on intestinal barrier function in stressed rats / 第二军医大学学报

Objective: To evaluate the effect of the galacto-oligosaccharides (GOS) on the intestinal mucosal tight junction and barrier function of rats with induced cold restraint stress. Methods: Forty Wistar rats were randomly divided into four groups: two cold resistant stress (CRS) groups fed with either a standard diet (CRS group) or 4g/kg GOS per day (CRS + GOS group) and two sham CRS groups fed with a standard diet (control group) or 4g/kg GOS per day (GOS group). All the four groupswere fed for a total of 10 days, and the CRS and CRS+GOS groups were subjected to cold restraint stress on the 10th day. Then the blood samples of all the four groups were collected via cardio puncture for determination of serum diamine oxidas (DAO) activity; finally all the rats were sacrificed and the intestinal tissues were collected for pathological and electronic microscopic examination, with the occludin mRNA level measured by real-time PCR and the occludin protein expression by immune-histological method. Results: Compared with the control, the serum DAO levels of CRS group and the CRS+GOS group were significantly increased (P<0.01); and that in the CRS group was significantly higher than that in the CRS+GOS group (P<0.01). The levels of occludin mRNA and protein expression were significantly decreased in the two CRS groups (P<0.01), and that in the CRS group was significantly lower than that in the CRS+GOS group (P<0.01); the serum DAO levels, the expressions of occludin mRNA and protein were not significantly different between the control and the GOS groups. Conclusion: Feeding with GOS can decrease plasma level of DAO in rats, increase expression of intestinal occludin mRNA and protein in rat ileum, indicating that GOS can improve the mucosal tight junction and intestinal barrier function.

Hydrolysis of galacto-oligosaccharides in soy molasses by α -galactosidases and invertase from Aspergillus terreus

Two α -galactosidase (P1 and P2) and one invertase present in the culture of Aspergillus terreus grown on wheat straw for 168 h at 28ºC were partially purified by gel filtration and hydrophobic interaction chromatographies. Optimum pH and temperatures for P1, P2 and invertase preparations were 4.5-5.0, 5.5 and 4.0 and 60, 55 and 65ºC, respectively. The K M app for ρ -nitrophenyl-α -D-galactopyranoside were 1.32 mM and 0.72 mM for P1 and P2, respectively, while the K M app value for invertase, using sacarose as a substrate was 15.66 mM. Enzyme preparations P1 and P2 maintained their activities after pre-incubation for 3 h at 50ºC and invertase maintained about 90 percent after 6 h at 55 ºC. P1 and P2 presented different inhibition sensitivities by Ag+, D-galactose, and SDS. All enzyme preparations hydrolyzed galacto-ologosaccharides present in soymolasses.

Duas α-galactosidases (P1 e P2) e uma invertase produzidas no sobrenadante da cultura do fungo Aspergillus terreus quando crescido por 168 h a 28ºC com farelo de trigo como fonte de carbono foram parcialmente purificadas por cromatografias de gel filtração e interação hidrofóbica. O pH e temperatura ótimos para as preparações P1, P2 e invertase foram entre 4,5-5,0, 5,5 e 4,0 e 60, 55 e 65ºC, respectivamente. O K M app para ρ-nitrofenil-α-D-galactopiranosideo foi 1.32 mM e 0.72 mM para P1 e P2, respectivamente. O valor de K M app para invertase usando sacarose como substrato foi de 15,66 mM. As preparações enzimáticas P1 e P2 mantiveram suas atividades após 3 h de pré-incubação a 50 ºC e a invertase manteve cerca de 90 por cento após 6 h a 55 ºC. P1 e P2 foram diferentemente sensíveis à inibição por Ag+, D-galactose e SDS. As preparações enzimáticas hidrolisaram os galactooligossacarídeos presentes em melaço de soja.

Revisión del papel de los oligosacáridos prebióticos en la prevención de infecciones gastrointestinales: [revisión] / Role of prebiotic oligosaccharides in prevention of gastrointestinal infections: [review]

Las enfermedades gastrointestinales siguen siendo un problema de salud pública mundial. El avance de la ciencia muestra que cambios en el balance adecuado de la microflora intestinal (MI) juegan un papel crucial en la patogénesis. La evidencia apunta a que una manera de modular esta MI es a través del uso de oligosacáridos prebióticos, que estimulan el crecimiento de bacterias benéficas y que a la vez aumentan la resistencia a la invasión por patógenos. Estudios con animales indican que el consumo de carbohidratos prebióticos podría estar implicado en la prevención y tratamiento de diarreas. En infantes humanos sanos, los estudios revelan que el consumo de mezclas de prebióticas (galactooligosacáridos/fructooligosacáridos, inulina/galactooligosacáridos) disminuyen la incidencia de fiebre, de infecciones y de patógenos gastrointestinales. Lo anterior representa un gran potencial para los alimentos funcionales que los contienen, principalmente las fórmulas infantiles. Sin embargo, los estudios de prevención de diarreas mediante el suministro de prebióticos en personas con una microflora intestinal alterada no son concluyentes, sobre todo aquellos practicados en ancianos, personas con problemas crónicos de inflamación intestinal y personas con diarreas asociadas a la toma de antibióticos. Lo anterior nos indica la necesidad de estudios bioquímicos y microbiológicos más profundos en humanos de diferentes edades y condiciones de salud intestinal, a fin de determinar en que condiciones, los prebióticos tienen algún efecto sobre las infecciones.

Gastrointestinal disorders are still a main world public health problem. Scientific progress shows that and inadequate balance in intestinal microbiota (IM) plays a crucial role in its pathogenesis. Evidence indicates that one way to modulate the IM is through the use of prebiotics. These oligosaccharides stimulate the growth of benefic bacteria and increase the resistance to invading pathogens. Research using animals show that the consumption of prebiotics could be implicated in prevention and treatment of diarrhea. Studies in healthy infants also indicate that the consumption of prebiotic mixtures (galactooligosaccharides/ fructooligosaccharides, inulin/ galactooligosaccharides) decreases the incidence of fever, infections and pathogens. These results represent a great potential for functional foods that contain prebiotics, mainly the infant formulas. However, results of other clinical studies for prebiotics effects on diarrhea are not conclusive. Specially those studies that include patients with an altered IM (like the elderly), patients with chronic intestinal inflammation and with diarrhea associated to antibiotic treatments. There is a need for more biochemical and microbiological studies in humans at different ages and intestinal health conditions, in order to determine when prebiotics may effectively function on infections.