Biofilms are responsible for the most prevalent oral infections such as caries, periodontal disease, and pulp and periapical lesions, which affect the quality of life of people. Antibiotics have been widely used to treat these conditions as therapeutic and prophylactic compounds. However, due to the emergence of microbial resistance to antibiotics, there is an urgent need to develop and evaluate new antimicrobial agents. This scoping review offers an extensive and detailed synthesis of the potential role of selenium nanoparticles (SeNPs) in combating oral pathogens responsible for causing infectious diseases. A systematic search was conducted up until May 2022, encompassing the MEDLINE, Embase, Scopus, and Lilacs databases. We included studies focused on evaluating the antimicrobial efficacy of SeNPs on planktonic and biofilm forms and their side effects in in vitro studies. The selection process and data extraction were carried out by two researchers independently. A qualitative synthesis of the results was performed. A total of twenty-two articles were considered eligible for this scoping review. Most of the studies reported relevant antimicrobial efficacy against C. albicans, S. mutans, E. faecalis, and P. gingivalis, as well as effective antioxidant activity and limited toxicity. Further research is mandatory to critically assess the effectiveness of this alternative treatment in ex vivo and in vivo settings, with detailed information about SeNPs concentrations employed, their physicochemical properties, and the experimental conditions to provide enough evidence to address the construction and development of well-designed and safe protocols.

Biofilm represents an organized multicellular community of bacteria having a complex 3D structure, formed by bacterial cells and their self-produced extracellular matrix. It usually attaches to any foreign body or fixation implant. It acts as a physical protective barrier of the bacteria from the penetration of antibodies, bacteriophages, granulocytes and biocides, antiseptics, and antibiotics. Biofilm-related infections will increase in the near future. This group of surgical site infections is the most difficult to diagnose, to suppress, to eradicate, and in general to manage. Multispecialty teams involved in all stages of care are an effective way to improve results and save resources and time for the benefit of patients and the health system. Significant steps have occurred recently in the prevention and development of clever tools that we can employ in this everlasting fight with the bacteria. Herein, we attempt to describe the nature and role of the \"biofilm\" to the specific clinical setting of surgical site infections in the field of orthopaedic trauma surgery.

Biofilm plays an important role in resisting the adverse environment, improving the taste and texture, and promoting the synthesis of flavor substances. However, to date, the findings on the effect of biofilm and dominating bacteria Bacillus on the ester synthesis in the Baijiu field have been largely lacked. Therefore, the objectives of the present study were to primarily isolate biofilm-producing microbes in the fermented grains, evaluate the stress tolerance capacity, and unveil the effect of biofilm and co-culture with Bacillus on the ester synthesis in the strong flavor Baijiu. Results indicated that after isolation and evaluation of stress-tolerance capacity, bacterial strain BG-5 and yeast strains YM-21 and YL-10 were demonstrated as mediate or strong biofilm-producing microbes and were identified as Bacillus velezensis, Saccharomycopsis fibuligera, and Zygosaccharomyces bailii, respectively. Solid phase microextraction/gas chromatography-mass spectrometer indicated that biofilm could enhance the diversity of esters while reduce the contents of ester. The scanning electron microscopy showed an inhibitory effect of B. velezensis on the growth of S. fibuligera, further restraining the production of esters. Taken together, both biofilm and B. velezensis influence the ester synthesis process. The present study is the first to reveal the biofilm-producing microorganisms in fermented grains and to preliminarily investigate the effect of biofilm on the ester synthesis in the Baijiu field.

Microbial resistance to antibiotics affects the control of clinical infections and is a growing concern in global public health. One important mechanism whereby microorganisms acquire resistance is biofilm formation. This context has led to the investigation of new antimicrobial substances from plants popularly used in folk medicine. In this work we studied the antimicrobial and antibiofilm activity of Zinnia peruviana roots, ziniolide (major root metabolite) and aerial parts against Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. The minimum inhibitory and minimum microbicidal concentration and inhibition of biofilm production was determined. All Z. peruviana extracts showed antimicrobial activity, but that corresponding to the roots was the most active one. The best inhibitory and microbicidal activity was detected against Gram-positive bacteria (0.039 to 0.078 mg ml-1 ). The acetonic extract from Z. peruviana leaves showed moderate activity against Gram-positive bacteria (0.625 mg ml-1 ). Acetonic extract of Z. peruviana flowers showed weak activity (1.25 to 5 mg ml-1 ). All the extracts tested showed inhibition of biofilm formation, as well as the ziniolide, however, roots and flowers extracts showed higher antibiofilm activity particularly against Staphylococcus, Listeria and Candida. The extracts tested may be a promising natural alternative for the control of microbial infections.

UNASSIGNED: Potentilla kleiniana Wight et Arn is a wide-spread wild plant in the mountainous areas in southern China. The whole herb has been used as a traditional herbal medicine to treat fever, arthritis, malaria, insect and snake bites, hepatitis, and traumatic injury. In vitro studies have reported the antibacterial activity use of the plant in traditional medicinal systems.
OBJECTIVE: The aim of this study was to investigate the inhibitory activity of total flavonoid from Potentilla kleiniana Wight et Arn (TFP) on methicillin-resistant Staphylococcus aureus (MRSA) in planktonic state and biofilm state.
METHODS: Antibacterial activities of TFP on planktonic MRSA were determined by agar diffusion method, microtiter plate assay and time-kill curve assay. Electrical conductivity, membrane permeability, membrane potential and autoaggregation were analyzed to study TFP effects on planktonic MRSA growth. Crystal violet (CV) staining and confocal laser scanning microscopy (CLSM) were analyzed to study TFP effects on aggregation and maturation of MRSA biofilm. After TFP treatment, extracellular polymeric substances (EPS) production were examined. Morphological changes in planktonic and MRSA biofilm following TFP treatment were determined with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Moreover, α-Toxin protein expression and adhesion-related gene expression were also determined.
RESULTS: The minimum inhibitory concentration (MIC) of TFP against MRSA was 20 μg/mL. The agar diffusion method and time-kill curve assay results indicated that TFP inhibited planktonic MRSA growth. TFP treatment significantly inhibited planktonic MRSA growth by inhibiting autoaggregation, α-hemolysin activity, α-Toxin protein expression, but increasing electrolyte leakage, membrane permeability and membrane potential and impacting cell structure. Moreover, TFP treatment significantly inhibited aggregation and maturation on MRSA biofilm by decreasing surface hydrophobicity, EPS production and adhesion-related gene expression.
CONCLUSIONS: The results of this trial provide scientific experimental data on the traditional use of Potentilla Kleiniana Wight et Arn for traumatic injury treatment and further demonstrate the potential of TFP to be developed as a novel anti-biofilm drug.

The emergence of multidrug-resistant bacteria is a growing problem and alternative therapies are being sought to effectively address this issue. The aim of this study is to assess a range of Escherichia coli strains\' susceptibility to Methylene Blue-mediated antimicrobial photodynamic therapy and determine if this is affected by their antibiotic-resistance profile. Two reference and twenty-four uropathogenic clinical E. coli strains were used in this study. All were tested in vitro for antimicrobial susceptibility against sixteen antibiotics. Strains underwent photodynamic treatments using the photosensitizer Methylene Blue with red light and tested in both planktonic and biofilm state. It was found that reference strain ATCC 25922 was susceptible to all tested antibiotics whereas reference strain ATCC 35218 showed resistance only to Ampicillin. With the exception of strains number 16 and 22, all of the isolated strains were multidrug-resistant according to the criteria established by the European Centre for Disease Prevention and Control and the Centre for Disease Control and Prevention, where acquired non-susceptibility to at least one agent in three or more antimicrobial categories is outlined. Photodynamic therapy induced more than 3 log10 colony-forming units\' reduction to all strains in planktonic state. Whereas when tested in biofilm state, two and a half times the original dose of methylene blue was necessary to cause a 3 log10 antimicrobial effect. There were statistically significant differences in susceptibility among the strains tested in both the planktonic and biofilm experiments. Nevertheless, antimicrobial photodynamic therapy could inactivate all multidrug-resistant strains in the planktonic and biofilm state.