Safety and Stability of Two Potentially Probiotic Lactobacillus Strains After In Vitro Gastrointestinal Transit

Abstract

According to FAO and WHO, probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Most probiotic bacteria used today belong to the genera Lactobacillus and Bifidobacterium and are of animal or human origin. The fundamental characteristic routinely evaluated in potential probiotics strains is their limited viability loss during gastrointestinal transit (GIT), but to date, no studies reported whether probiotics, besides viability, still also maintain their beneficial properties intact. To study this aspect, we considered two strains, Lactobacillus rhamnosus DTA 79 and L. paracasei DTA 83, previously characterised for the presence of some probiotic properties, isolated from faeces of 7-to 21day-old babies. Here, we examined some additional properties, namely antibiotic resistance, resistance to lysozyme, presence of haemolytic activity and inhibition of pathogen biofilm formation. We then tested the effect of in vitro GIT on all these features and our results show evidence that this procedure had in some cases limited and in others no significant effects on them. Additionally, we examined the gastrointestinal resistance of the strains after skim milk fermentation and successive storage of the product for 20 and 40 days at refrigeration temperature, to see whether prolonged storage could weaken cell resistance to GIT. Our results demonstrate that a protracted refrigeration period before in vitro GIT did not affect or influenced very weakly this essential probiotic property.

Growth Parameters and Survivability of Saccharomyces boulardii for Probiotic Alcoholic Beverages Development

“…To evaluate S. boulardii survivability under in vitro gastrointestinal conditions, 10 mL aliquots from the polynomial mathematical model validation experiment samples were collected as described above. In vitro GI treatment was carried out as reported by Guerra et al (2018) and Lemos Junior et al (2019). GI base juice was formulated as follows: 0.11 g L –1 calcium chloride, 1.12 g L –1 potassium chloride, 2.0 g L –1 sodium chloride, and 0.4 g L –1 potassium dihydrogen phosphate.…”

Craft Beers Fermented by Potential Probiotic Yeast or Lacticaseibacilli Strains Promote Antidepressant-Like Behavior in Swiss Webster Mice

“…Potential probiotic L. paracasei DTA 81 was isolated from stools of infants (1 to 3 weeks old) assisted by the Human Milk Bank and the Neonatal Intensive Care Unit of Fernandes Figueira Institute (FIOCRUZ) located in the state of Rio de Janeiro, Brazil. It was identified by Gram staining, catalase reaction, and API 50 CH tests (BioMerieux, Marcy-l'Etoile, France), as well as by sequencing the 16S rDNA region [9,10]. Potential probiotic S. boulardii 17 was purchased at a local pharmacy (Valença, Rio de Janeiro, Brazil), as freeze-dried culture.…”

“…Additionally, the strain is ɣ-hemolytic (absent of β-hemolytic activity when grown on MRS agar containing 5% (w/v) sheep blood). L. paracasei DTA 81 also presented an ability to adhere to HT-29 cells, approximately ten times higher than the reference widespread probiotic commercial strain L. rhamnosus GG [8,9]. L. paracasei DTA-81 easily assimilate glucose, showing restrictions to assimilate maltose [10].…”

Harnessing Microbes for Sustainable Development: Food Fermentation as a Tool for Improving the Nutritional Quality of Alternative Protein Sources

“…Considering the food market, yogurt and fermented dairy products may be the most popular among consumers, but fermented cereals, legumes, vegetables, and fruits have recently attracted consumers' attention, regaining popularity [15]. One of the main benefits of fermented food is the ingestion of beneficial microbes that can contribute to intestinal microbiota populations [17,18] or can impact resident microbial communities via different mechanisms: through trophic interactions, a direct alteration in fitness, or an indirect alteration in fitness through altered production of host-derived molecules [19].…”