Lactic Acid Bacteria Co-Encapsulated with Lactobionic Acid: Probiotic Viability during In Vitro Digestion

Synbiotic products are a type of functional food with great potential due to consumer interest in foods that improve health and/or reduce the risk of certain diseases. In this study, synbiotic macrocapsules were developed using Lactobacillus paracasei CBA L74 as probiotic and lactobionic acid (LBA) as prebiotic. Firstly, the probiotic was proven to be able to use LBA as the only substrate source checking their growth and lactic acid production. Then, four different types of capsules were produced using sodium alginate as matrix and different hardener solutions (CaCl2 and chitosan). The macrocapsules were characterised regarding their strength, and the best performing ones were used for further analysis. In order to obtain a synbiotic capsule characterized by a longer stability time due to low water activity, the capsules were dried using freeze and thermal drying. Successively, to revitalize the microorganisms, the capsules were rehydrated in two different media (saline solution and yogurt), subjected to simulated in vitro digestion tests and visually characterised. In addition, their viability over time was assessed. As a result, L. paracasei was able to grow using LBA as the only source of carbon with better production of lactic acid for prolonged periods. The more resistant freeze- and thermal-dried capsules showed differences in rehydration kinetics, and visual changes were also observed. In simulated in vitro digestion tests, capsules rehydrated in yogurt showed the best results in terms of survival. Regarding their viability over time, the importance of the use of chitosan was noted.

Enhanced Antibacterial Potential of Amoxicillin against Helicobacter pylori Mediated by Lactobionic Acid Coated Zn-MOFs

H. pylori (Helicobacter pylori) causes a common chronic infectious disease and infects around 4.4 billion people worldwide. H. pylori was classified as a member of the primary class of stomach cancer (stomach adenocarcinoma). Hence, this study was conducted to design a novel lactobionic acid (LBA)-coated Zn-MOFs to enhance bactericidal activity of Amoxicillin (AMX) against H. pylori. The synthesized Zn-MOFs were characterized by various techniques which included Dynamic Light Scattering (DLS), Fourier Transform Infrared (FT-IR) Spectroscopy, Powder X-ray diffraction, scanning electron microscope, and atomic force microscope. They were capable of encapsulating an increased amount of AMX and investigated for their efficacy to enhance the antibacterial potential of their loaded drug candidate. Interestingly, it was found that LBA-coated Zn-MOFs significantly reduced the IC50, MIC, and MBIC values of AMX against H. pylori. Morphological investigation of treated bacterial cells further authenticated the above results as LBA-coated Zn-MOFs-treated cells underwent complete distortion compared with non-coated AMX loaded Zn-MOFs. Based on the results of the study, it can be suggested that LBA-coated Zn-MOFs may be an effective alternate candidate to provide new perspective for the treatment of H. pylori infections.

Evaluation of Microencapsulated Synbiotic Preparations Containing Lactobionic Acid

The aim of this paper was to assess the prebiotic properties of lactobionic acid in the human gastrointestinal model. Five different strains of probiotic, or potentially probiotic, bacteria were used in the microencapsulation process; these were Lactobacillus casei Shirota, Lactococcus lactis ATCC1, Lactobacillus fermentum, Bifidobacterium bifidum DSM 20456, and Bifidobacterium bifidum DSM 20082. Starch with a concentration of 4% (w/v) and a degree of substitution of 0.03 was used to produce the microcapsules. The alginian microcapsules we produced functioned as a protective barrier for the probiotic microorganisms closed in them, protecting them from adverse conditions in the human digestive tract. The microorganisms could thus survive the encapsulation process and the in vitro model digestion process while retaining the ability to produce biomass. Factors such as pH and time affect the solution of alginate microcapsules. The capsule solution began when a pH of 7.4 was reached; this corresponded to pH in the target probiotic site, an in vitro model of the colon. The capsules had completely dissolved after 24 h of digestion at a pH of 8. The addition of lactobionic acid stimulated the growth of probiotic and potentially probiotic bacteria, thus confirming its prebiotic properties.