Tannins represent a heterogeneous group of high-molecular-weight polyphenols that are ubiquitous among plant families, especially in cereals, as well as in many fruits and vegetables. Hydrolysable and condensed tannins, in addition to phlorotannins from marine algae, are the main classes of these bioactive compounds. Despite their low bioavailability, tannins have many beneficial pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, anticancer, and cardioprotective effects. Microbiota-mediated hydrolysis of tannins produces highly bioaccessible metabolites, which have been extensively studied and account for most of the health effects attributed to tannins. This review article summarises the effect of the human microbiota on the metabolism of different tannin groups and the expected health benefits that may be induced by such mutual interactions. Microbial metabolism of tannins yields highly bioaccessible microbial metabolites that account for most of the systemic effects of tannins. This article also uses explainable artificial intelligence to define the molecular signatures of gut-biotransformed tannin metabolites that are correlated with chemical and biological activity. An understanding of microbiota–tannin interactions, tannin metabolism-related phenotypes (metabotypes) and chemical tannin-metabolites motifs is of great importance for harnessing the biological effects of tannins for drug discovery and other health benefits.

The emergence and spread of metallo-beta-lactamase–producing multidrug-resistant (MDR) Klebsiella pneumoniae is a serious public health threat, which is further complicated by the increased prevalence of colistin resistance. The link between antimicrobial resistance acquired by strains of Klebsiella and their unique metabolic capabilities has not been determined. Here, we reconstruct genome-scale metabolic models for 22 K. pneumoniae strains with various resistance profiles to different antibiotics, including two strains exhibiting colistin resistance isolated from Cairo, Egypt. We use the models to predict growth capabilities on 265 different sole carbon, nitrogen, sulfur, and phosphorus sources for all 22 strains. Alternate nitrogen source utilization of glutamate, arginine, histidine, and ethanolamine among others provided discriminatory power for identifying resistance to amikacin, tetracycline, and gentamicin. Thus, genome-scale model based predictions of growth capabilities on alternative substrates may lead to construction of classification trees that are indicative of antibiotic resistance in Klebsiella isolates.

Otitis media (OM) is a frequent infectious condition that affects the middle ear especially in children. The purpose of this project was to create fenchone-augmented novasomes to enhance the trans-tympanic penetration of levofloxacin (LFX) and improve its antibacterial efficacy. Novasomes were formulated using the ethanol injection technique and optimized using a 2 ³ factorial design. The factors analyzed included the stearic acid to drug ratio (A), cholesterol to fenchone ratio (B), and surfactant concentration (%) (C). The optimization feature of Design-Expert® software was utilized to identify the optimal formulation by minimizing particle size (PS) and poly-dispersity index (PDI) while maximizing entrapment efficiency (EE%) and the absolute value of the zeta potential (ZP). The best formulation achieved a desirability of 0.964, with an EE% of 73.39%, a PS of 179.25 nm, and a ZP of − 31.95 mV. The formulation will be subjected to additional evaluations, including in vitro, ex vivo, microbiological, and in vivo testing. A thorough in vitro analysis revealed a biphasic release profile, significant stability, and a spherical morphology. Novasomes exhibited greater ex vivo permeation and superior flux values compared to the LFX solution. The optimum formula demonstrated high otic tolerance. The optimized formula demonstrated markedly enhanced antibacterial activity, with significantly lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against Staphylococcus aureus and Pseudomonas aeruginosa compared to the drug solution. Moreover, it exhibited superior biofilm inhibition, even at sub-MIC concentrations, underscoring its efficacy. These findings highlight the potential of LFX-loaded novasomes as an efficient non-invasive method for managing middle ear infections.

This study introduces and statistically optimizes novel Tetra-Synergistic Bilosomes (TSB), an advanced nano-platform for topical delivery of voriconazole (VOR) in otomycosis therapy. The term “Tetra-Synergistic” reflects the incorporation of four complementary components: Cremophor® EL, sodium deoxycholate, Brij® 58, and Brij® S2, working in synergy to enhance therapeutic efficacy. TSB was fabricated using the thin-film hydration method and optimized through a 2 ³ D-optimal design. Three formulation factors were investigated: Cremophor® EL: VOR ratio, sodium deoxycholate: cholesterol ratio, and Brij® 58: Brij® S2 ratio, with the optimization goal of maximizing EE%, minimizing vesicular size, and maintaining ZP within the acceptable stability range. The model demonstrated excellent predictability, achieving a desirability value of 0.888. The optimized TSB exhibited high EE% (91.6%), a suitably small VS (217.9nm), and stable ZP (− 24.1mV). FTIR confirmed VOR entrapment, while TEM revealed nano-sized spherical vesicles. Moreover, TSB displayed a biphasic In-vitro release profile and remained stable for three months under refrigeration. Importantly, microbiological evaluation confirmed the superior antifungal performance of TSB. Compared with VOR suspension, TSB showed a larger inhibition zone, a lower minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC), and a faster fungicidal effect, eradicating fungal growth in 33% less time. Ex-vivo permeation studies revealed a 2.18-fold enhancement ratio, supported by confocal laser scanning microscopy confirming deeper tissue penetration. Histopathological analysis further validated the safety of topical application without any tissue damage. Collectively, these results establish TSB as a pioneering, microbiologically potent, and clinically promising nano-vesicular system for the effective management of otomycosis.