Given the urgent need for novel methods to control the spread of multidrug-resistant microorganisms, this study presents a green synthesis approach to produce silver nanoparticles (AgNPs) using the bark extract from Anadenanthera colubrina (Vell.) Brenan var. colubrina. The methodology included obtaining the extract and characterizing the AgNPs, which revealed antimicrobial activity against MDR bacteria. A. colubrina species is valued in indigenous and traditional medicine for its medicinal properties. Herein, it was employed to synthesize AgNPs with effective antibacterial activity (MIC = 19.53–78.12 μM) against clinical isolates from the ESKAPEE group, known for causing high hospitalization costs and mortality rates. Despite its complexity, AgNP synthesis is an affordable method with minimal environmental impacts and risks. Plant-synthesized AgNPs possess unique characteristics that affect their biological activity and cytotoxicity. In this work, A. colubrina bark extract resulted in the synthesis of nanoparticles measuring 75.62 nm in diameter, with a polydispersity index of 0.17 and an average zeta potential of −29 mV, as well as low toxicity for human erythrocytes, with a CC₅₀ value in the range of 961 μM. This synthesis underscores its innovative potential owing to its low toxicity, suggesting applicability across several areas and paving the way for future research.

Background/Objectives: Wounds from burns are susceptible to infections, allowing multidrug-resistant microorganisms to complicate treatments and patient recovery. This highlights the development of new strategies to control these microorganisms. This work evaluated the antibacterial activity of hydrogels containing biogenic silver nanoparticles (bio-AgNP) and Origanum vulgare essential oil (OEO) against multidrug-resistant bacteria. Methods: The formulations were subjected to organoleptic, pharmacotechnical, and stability characterization and antimicrobial activity assessment by time–kill tests and alternative methods, an ex vivo model using porcine skin, and an in vivo model using Galleria mellonella. Results: All hydrogels maintained their stability after the thermal stress. The hydrogel containing bio-AgNP + OEO 1% (HAgNP + OEO1) presented bactericidal effectiveness, within 2 h, against both Gram-positive and Gram-negative multidrug-resistant bacteria in the time–kill test. For alternative testing, HAgNP + OEO1 was compared with 1% silver sulfadiazine (SS) and the base formulation. In the ex vivo test, both HAgNP + OEO1 and SS treatments showed a similar reduction in superficial washing of the burn for S. aureus 999, while for P. aeruginosa, the reduction was more expressive for SS treatment. In the burn tissue, HAgNP + OEO1 treatment was more effective against S. aureus 999, while for P. aeruginosa 1461, both formulations were similarly effective. In the Galleria mellonella test, survival rates after 48 h were 84% for the control group (base) and 50% for both HAgNP + OEO1 and SS treatment groups. Conclusions: This study demonstrates that the hydrogel combining antimicrobials is effective against multidrug-resistant microorganisms, offering a promising alternative for the treatment of infected burns.

The demand for sustainable cosmetics leads to the search for natural and biotechnological ingredients. The present study reports the development of a multifunctional lip moisturizer containing levan (LEV) from Bacillus subtilis natto, sophorolipids (SOPs) from Starmerella bombicola and Citrus paradisi (OCP) essential oil, using a simplex-centroid experimental design. The formulations were evaluated physicochemically, pharmacotechnically and by DPPH assay. The optimized formulation was selected through the Response Surface Method, and the evaluation of its efficiency in lip hydration was carried out using the bioimpedance method and sensory analysis. The formulations showed pH compatibility with lips and remained stable after a centrifuge test and thermal stress. Spreadability varied between 415.3 and 1217.1 mm², moisture retention was above 95% and antioxidant capacity was around 50% for all formulations. The optimized formulation, containing 0.4% LEV and 0.8% SOF, maintained the lip hydration already shown by the participants; 85% of them reported improvement in this aspect. For the first time, LEV and SOP were incorporated in lip moisturizers, which is an environmentally friendly product with marketing potential. Furthermore, the use of the Skin Analyzer Digital equipment, a low-cost and non-invasive technique, to evaluate the effectiveness of lip products is innovative; this methodology may help in the development of future cosmetology studies.

The demand for sustainable cosmetics leads to the search for natural and biotechnology ingredients. The present study reports the development of multifunctional lip moisturizer containing levan (LEV) from Bacillus subtilis natto, sophorolipids (SOP) from Starmerella bombicola and Citrus paradisi (OCP) essential oil , using simplex-centroid experimental design. The formulations were evaluated physicochemically, pharmacotechnically and by DPPH assay. The optimized formulation was selected through Response Surface Method and the evaluation of its efficiency in lip hydration was carried out using bioimpedance method and sensory analysis. The formulations showed pH compatible with the lip region and remained stable after centrifuge test and thermal stress in preliminary stability. Spreadability varied between 415.3 and 1217.1 mm2, moisture retention was above 95%, and antioxidant capacity was around 50% for all formulations. The optimized formulation, containing 0.4% LEV and 0.8% SOF, helped to maintain the lip hydration already shown by the participants; 85% of them reported improvement in this aspect. The incorporation of these actives is innovative and helps in the development of future works, through the use of a new non-invasive and low-cost technique, not previously described in other studies, in association with relevant sensory analyzes in the field of cosmetology.

Background/Objectives: Bacterial resistance to antimicrobials has become a public health problem worldwide, limiting the effectiveness of conventional treatments. Therefore, combination antimicrobial therapy has been proposed as a strategy to combat multidrug-resistant bacteria. This study aimed to investigate the antibacterial effects of ciprofloxacin (CIP) in binary combinations with Cinnamomum cassia (L.) J. Presl. (CEO) and Origanum vulgare L. (OEO) essential oils against Acinetobacter baumannii, Klebsiella quasipneumoniae, Pseudomonas paraeruginosa, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA). Methods: The hemolytic activity was evaluated for the compounds individually and when combined. The antimicrobial activity was performed by broth dilution in double-antimicrobial gradient and time-kill assays. Results: The CEO–CIP and OEO–CIP combinations demonstrated hemolytic activity in human erythrocytes of 4.04 to 3.35% and 3.39 to 2.29%, respectively, and presented synergistic, additive, and indifferent antibacterial effects. The CEO–CIP combination significantly reduced CIP minimal inhibitory concentration from 256 to 0.125 µg/mL against MRSA. OEO–CIP was bactericidal against P. paraeruginosa and S. aureus; meanwhile, the CEO–CIP combination showed bactericidal activity against P. paraeruginosa, but reduced S. aureus viability by only 1.83 log after 24 h. Conclusions: These findings demonstrate the combination of CEO–CIP against A. baumannii, K. quasipneumoniae, P. paraeruginosa, S. aureus, and MRSA, in addition to hemolytic activity below 5% at the tested concentrations. Although limited to in vitro conditions, these results highlight the combination’s therapeutic potential and emphasize the necessity for further investigation into its mechanisms of action and in vivo toxicity.