Survival of Planktonic and Sessile Cells of Lactobacillus rhamnosus and Lactobacillus reuteri upon Exposure to Simulated Fasting-State Gastrointestinal Conditions

Comparative analysis of risedronate and its regioisomers synthesized via microwave-assisted method: bone affinity, cytotoxicity, permeability, and therapeutic potential

BACKGROUND

Bisphosphonates (BPs) are widely used for treating bone diseases such as osteoporosis due to their strong affinity for hydroxyapatite (HA) in bones. Minor structural variations among BPs can significantly affect their therapeutic potential. This study aimed to synthesize risedronate (RSD) and its two regioisomers (2-RSD, 4-RSD) and investigate the impact of these variations on bone affinity, permeability, and cytotoxicity.

METHODS

RSD and its regioisomers were synthesized using a microwave-assisted method. Bone affinity was assessed through sorption studies on HA and two polymer-ceramic materials mimicking bone properties. Compound permeability was predicted using the Parallel Artificial Membrane Permeability Assay (PAMPA). Cytotoxicity was evaluated by analyzing the response of bacterial cells to BPs using metabolic activity assays.

RESULTS

2-RSD demonstrated a higher bone affinity and similar permeability than commercially available RSD. 2-RSD also showed reduced cytotoxicity in bacterial cell assays, indicating enhanced biocompatibility. These findings suggest that minor structural changes can lead to significant differences in therapeutic efficacy.

CONCLUSIONS

The study highlights the potential of the 2-RSD as a more effective treatment for bone diseases. Structural variations in BPs can greatly influence their biological properties, paving the way for the development of improved therapeutic agents.

The Evolution of Human Probiotics: Challenges and Prospects

In recent years, the intestinal microbiota has been found to greatly influence a number of biological processes important for human health and longevity. Microbial composition changes easily in response to external factors, such as an unbalanced diet, lack of physical activity, and smoking. Probiotics are a key factor in maintaining the optimal composition of the intestinal microbiota. However, a number of important questions related to probiotics, such as indication for prescription, comparative efficacy of monostrain and multistrain probiotics, methods of delivery, and shelf life, remain unresolved. The aim of this review is to highlight existing issues regarding probiotic production and their prescription. The review presents the most recent findings regarding advantages and efficacy of monostrain and multistrain probiotics, preservation of probiotic strains in capsules and microcapsules, production of probiotics in the form of biofilms for improved efficacy and survival, and results of clinical studies evaluating the benefits of probiotics against different pathologies. We believe that this work will be of interest to physicians and researchers alike and will promote the development of new probiotics and ensuing regimens aimed at the treatment of various diseases.

Biofilm dynamics: linking in situ biofilm biomass and metabolic activity measurements in real-time under continuous flow conditions

The tools used to study biofilms generally involve either destructive, end-point analyses or periodic measurements. The advent of the internet of things (IoT) era allows circumvention of these limitations. Here we introduce and detail the development of the BioSpec; a modular, nondestructive, real-time monitoring system, which accurately and reliably track changes in biofilm biomass over time. The performance of the system was validated using a commercial spectrophotometer and produced comparable results for variations in planktonic and sessile biomass. BioSpec was combined with the previously developed carbon dioxide evolution measurement system (CEMS) to allow simultaneous measurement of biofilm biomass and metabolic activity and revealed a differential response of these interrelated parameters to changing environmental conditions. The application of this system can facilitate a greater understanding of biofilm mass-function relationships and aid in the development of biofilm control strategies.

Unveiling the potentials of bacteriocin (Pediocin L50) from Pediococcus acidilactici with antagonist spectrum in a Caenorhabditis elegans model

Human-milk-based probiotics play a major role in the early colonization and protection of infants against gastrointestinal infection. We investigated potential probiotics in human milk. Among 41 Lactic acid bacteria (LAB) strains, four strains showed high antimicrobial activity against Escherichia coli 0157:H7, Listeria monocytogenes ATCC 15313, Bacillus cereus ATCC 14576, Staphylococcus aureus ATCC 19095, and Helicobacter pylori. The selected LAB strains were tested in simulated gastrointestinal conditions for their survival. Four LAB strains showed high resistance to pepsin (82%-99%), bile with pancreatine stability (96%-100%), and low pH (80%-94%). They showed moderate cell surface hydrophobicity (22%-46%), auto-aggregation abilities (12%-34%), and 70%-80% co-aggregation abilities against L. monocytogenes ATCC 15313, S. aureus ATCC 19095, B. cereus ATCC 14576, and E. coli 0157:H7. All four selected isolates were resistant to gentamicin, imipenem, novobiocin, tetracycline, clindamycin, meropenem, ampicillin, and penicillin. The results show that Pediococcus acidilatici is likely an efficient probiotic strain to produce < 3 Kda pediocin-based antimicrobial peptides, confirmed by applying amino acid sequences), using liquid chromatography mass spectrometry and HPLC with the corresponding sequences from class 2 bacteriocin, and based on the molecular docking, the mode of action of pediocin was determined on LipoX complex, further the ¹³C nuclear magnetic resonance structural analysis, which confirmed the antimicrobial peptide as pediocin.