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Biofilms play an essential role in chronic and healthcare-associated infections and are more resistant to antimicrobials compared to their planktonic counterparts due to their (1) physiological state, (2) cell density, (3) quorum sensing abilities, (4) presence of extracellular matrix, (5) upregulation of drug efflux pumps, (6) point mutation and overexpression of resistance genes, and (7) presence of persister cells. The genes involved and their implications in antimicrobial resistance are well defined for bacterial biofilms but are understudied in fungal biofilms. Potential therapeutics for biofilm mitigation that have been reported include (1) antimicrobial photodynamic therapy, (2) antimicrobial lock therapy, (3) antimicrobial peptides, (4) electrical methods, and (5) antimicrobial coatings. These approaches exhibit promising characteristics for addressing the impending crisis of antimicrobial resistance (AMR). Recently, advances in the micro- and nanotechnology field have propelled the development of novel biomaterials and approaches to combat biofilms either independently, in combination or as antimicrobial delivery systems. In this review, we will summarize the general principles of clinically important microbial biofilm formation with a focus on fungal biofilms. We will delve into the details of some novel micro- and nanotechnology approaches that have been developed to combat biofilms and the possibility of utilizing them in a clinical setting.

The present study focuses on the antimicrobial activity and safety aspect of lactobacilli strains isolated from the anogenital region. Sixty-two lactobacilli strains were isolated from 52 healthy, non-menstruating women from a local health clinic in Puchong, Selangor, Malaysia and confirmed by 16S rDNA sequencing. The samples were collected by sterile cotton swabs and directly streaked onto De Man, Rogosa, Sharpe agar prior to transportation to the lab on ice. A selective preliminary screening against several Candida albicans and Candida glabrata strains identified 5 promising lactobacilli strains for the subsequent assays; L. delbreuckii 45E, L. fermentum 28E, L. mucosae 28C, L. reuteri 29A and L. reuteri 29B. A follow-up antibacterial assay identified L. delbreuckii 45E, L. reuteri 29A and L. reuteri 29B as the lactobacilli strains with the highest inhibitory activity. Subsequent assays including haemolytic activity, susceptibility to antibiotics, quantification of D/l-lactic acid and H2O2 production as well as bile salt hydrolase (BSH activity) indicated that L. reuteri 29B was a promising probiotic candidate. An acute toxicity study in vivo involving the administration of 1 × 108, 1 × 109 and 1 × 1010 cfu/mouse/day demonstrated that L. reuteri 29B did not exert any adverse effects towards the mice which were evident through the absence of pathological changes in the histological examination and blood test. There was also a lack of bacterial translocation as confirmed by Random Amplified Polymorphic DNA (RAPD). The present study highlights the possibility of utilising L. reuteri 29B as a probiotic. It also demonstrates the possibility of isolating potential probiotics from the anogenital region.

Introduction: Lactobacilli are well-documented probiotics that exert health benefits on their host. They exhibit characteristics that make them potential alternative treatments to address the antimicrobial resistance conundrum and diseases. Their mechanism of action varies with strain and species. Five lactobacilli strains previously isolated from the anogenital region were subjected to several assessments highlighted in the FAO/WHO document, ‘Guidelines for the Evaluation of Probiotics in Food’ to determine its suitability as potential probiotics. Methods: The five lactobacilli strains were subcultured onto Man de Rogosa agar (MRS). Their ability to auto- and co-aggregate was determined spectrophotometrically. Simultaneously, the cell surface hydrophobic properties of these strains towards xylene and toluene were evaluated using the microbial adhesion to hydrocarbon (MATH) test. The lactobacilli strains were also tested for their ability to withstand acid, bile and spermicide to determine their level of tolerance. Results: Lact. reuteri 29A, L. delbrueckii 45E and L. reuteri 29B exhibited the highest degree of auto- and co-aggregation properties. These lactobacilli strains also demonstrated high cell surface hydrophobicity, with the exception of L. delbrueckii 45E. Further tests to evaluate the isolated lactobacilli tolerance identified L. reuteri 29B as the most tolerant strain towards low pH (pH 2.5 for 4 h), high bile concentration (0.5% for 4 h) and high spermicides concentration (up to 10%). Conclusion: Out of the five lactobacilli strains which possessed high antimicrobial activities, L. reuteri 29B portrayed the best probiotic qualities with good auto- and co-aggregation abilities and high tolerance against acid, bile and spermicide.

The female urogenital tract has long been recognised as a reservoir for a great diversity of microorganisms. The most prominent species isolated from this anatomical site among healthy women has been identified as lactobacilli. Previous studies conducted on these species indicate that they function to maintain a healthy reproductive system and protect the host from harm. In this study, the characteristics and properties of several lactobacilli strains isolated from the urogenital tract and perianal region of healthy female participants were evaluated to identify potential probiotic strains. The lactobacilli strains were isolated from twenty out of fifty-two Malaysian women wherein a total of sixty-two species of lactobacilli were identified using 16S rDNA sequencing. The most common species isolated in the present study were identified as L. reuteri (n = 14), L. mucosae (n = 12), L. fermentum (n = 10) and L. oris (n = 9). The least common species were L. vaginalis (n = 5), L. gasseri (n = 4), L. delbrueckii (n = 3), L. jensenii (n = 2) followed by L. salivarius, L. plantarum and L. rhamnosus (all with n = 1 isolate each). All lactobacilli strains demonstrated the ability to reduce the growth of several reference and clinical strains of Candida albicans and Candida glabrata, as observed in the broth microdilution assay. Five of the lactobacilli strains with potent anti-Candida effects were selected for subsequent assays based on the characteristics exhibited. These five lactobacilli strains exhibited fairly strong antimicrobial effects against ten of the pathogens tested as observed from the agar plug diffusion assay. All five lactobacilli strains could produce varying degrees of hydrogen peroxide, H2O2 as evaluated using 3’3, 5’5 tetramethylbenzidine (TMB) agar. Meanwhile, the differences in lactic acid production among the five strains indicate that the growth inhibitory mechanisms may differ for each strain. Besides that, the findings from the autoaggregation and