No abstract

La mayoría de microorganismos considerados como probióticos, tienen un papel importante en el mejoramiento de la función intestinal, tanto para la salud humana como animal. Gran parte de estos microorganismos probióticos, son muy sensibles a condiciones ambientales como la humedad, la temperatura, la concentración de oxígeno, las sales biliares, y el pH estomacal y, al ser procesados o almacenados como alimentos funcionales se puede ver afectada su viabilidad. Debido a esto, es necesario desarrollar condiciones protectoras que garanticen la viabilidad y actividad de estos microorganismos cuando son adicionados y procesados en matrices alimentarias, y asegurar que sean liberados en el intestino donde se precisa su acción. De acuerdo a lo anterior, el presente proyecto propone evaluar la influencia de la técnica de secado por aspersión con maltodextrina más inulina sobre la viabilidad de un consorcio de tres tipos de bacterias probióticas ampliamente utilizadas en la industria alimentaria.

The microbial diversity of Lobatus gigas has not been thoroughly studied despite of them is a specie endangered. Knowledge of microbiota may help to improve the conservation and cultivation of this species. The objective of this study was to evaluate the bacterial populationsassociated with the gonad and the gut compartments of the wild endangered L. gigas from the Caribbean Seaflower Biosphere Reserve, using microbiological methods and culture-independent molecular tools. The genetic profiles of the bacterial populations were generated and Temporal Temperature Gradient Electrophoresis (TTGE) was used to compare them with total DNA. A genetic and statistical analysis of the bacterial communities revealed a low level of diversity in gonad tissue based on the number of bands detected using TTGE. In addition, statistical differences in bacterial community structure were found between the foregut and hindgut tissue of L. gigas. The dominant phylogenetic affiliations of the gonad bacteria, as determined using 16S rRNA gene sequencing, belong to Ralstonia (50%). The possible involvement of this genus in the reproduction and development of the conch is discussed. On the other hand, the bacterial phylotypes from foregut and hindgut included members of  Alphaproteobactera (12.5%), Betaproteobacteria (12.5%), Gammaproteobacteria (12.5%), Bacilli (31.25%), Clostridia (6.25%), Actinobacteria (6.25%), Mollicutes (6.25%) and Deinococci (6.25%) classes. Knowing the composition of the gonad and foregut and hindgut bacteria of L. gigas is the first step toward exploring the proper management of this species, as well as provides useful information to future researches that allow a better understanding of the role of these bacterial populations in the health and reproductive rate of L. gigas.

There is increasing evidence that the diet and nutritional status of women during pregnancy and lactation can modulate the microbiota of their milk and, therefore, the microbiota of the infant. An observational, descriptive, and cross-sectional study was carried out in a group of lactating women. Dietary intake during gestation and the first trimester of lactation was evaluated, and the microbiota was analyzed by 16S ribosomal RNA (rRNA) sequencing using the Illumina platform. Globally, Streptococcus spp. (32%), Staphylococcus spp. (17.3%), Corynebacterium spp. (5.1%) and Veillonella spp. (3.1%) were the predominant bacterial genera. The consumption of simple carbohydrates in gestation (rho = 0.55, p ≤ 0.01) and lactation (rho = 0.50, p ≤ 0.01) were positively correlated with Enterobacter spp. In lactation, a negative correlation was observed between the intake of simple carbohydrates and the genus Bifidobacterium spp. (rho = −0.51 p ≤ 0.01); furthermore, a positive correlation was identified between the intake of folic acid and Akkermansia spp. (rho = 0.47, p ≤ 0.01). Amplicon sequence variants (ASVs) associated with the delivery mode, employment relationship, the baby’s gender, birth weight, the Body Mass Index (BMI) of the breastfeeding woman, and gestational weight gain were recovered as covariates in a linear mixed model. The results of this research showed that the maternal nutritional status and diet of women during gestation and lactation could modulate the microbiota of breast milk.