Topical gel containing Polysiloxanes and hyaluronic acid for skin scar: Formulation design, characterization, and In vivo activity

Development and Evaluation of the Antibacterial Properties of an Experimental Herbal Gel Against Cariogenic Bacteria

BACKGROUND

Recently, products with antibacterial properties derived from medicinal plants have increased as an alternative to conventional drugs. Thus, this study aimed to formulate and evaluate the antibacterial activity of an experimental gel based on Grindelia tarapacana essential oil in a bacterial consortium.

MATERIAL AND METHODS

The composition of the essential oil (EO) was determined using gas chromatography-mass spectrometry (GC-MS). The antibacterial activity of the EO against Streptococcus mutans ATCC 25175, Streptococcus sanguinis ATCC 10556, and Streptococcus salivarius ATCC 13419 was evaluated using an Agar disc diffusion and minimum inhibitory concentration methods. Five formulations of the experimental gel were prepared at 0.25%, 0.5%, 1%, 1.5%, and 2% (v/v). The antibacterial susceptibility test was evaluated using an Agar-Well diffusion assay against a bacterial consortium of S. mutans, S. sanguinis, and S. salivarius. The physical properties, pH, spreadability, gel morphology, phase separation, and drug release were evaluated. The experimental gels were compared with a chlorhexidine gel. Data were analyzed with one-way ANOVA and Kruskal-Wallis tests with a significant level of 5%.

RESULTS

The major components of the EO were bornyl acetate, α-isomethyl-E-nerolidol, germacrene B, E-nerolidol, α-cedrene-epoxide, fokienol, and 10-epi-γ-eudesmol. All formulations were effective in inhibiting bacterial growth. The 2% concentration presented inhibition zones (18.14 ± 1.01 mm) similar to those observed for the chlorhexidine gel (p > 0.05). All formulations were stable, without signs of separation, with adequate physical properties, and no significant differences were observed regarding the drug content with the chlorhexidine gel (p > 0.05).

CONCLUSIONS

The experimental gels based on G. tarapacana EO presented good physicochemical properties and were highly effective in inhibiting the growth of a cariogenic bacterial consortium.

OH End-Capped Silicone as an Effective Nucleating Agent for Polylactide-A Robotizing Method for Evaluating the Mechanical Characteristics of PLA/Silicone Blends

Current research on materials engineering focuses mainly on bio-based materials. One of the most frequently studied materials in this group is polylactide (PLA), which is a polymer derived from starch. PLA does not have a negative impact on the natural environment and additionally, it possesses properties comparable to those of industrial polymers. The aim of the work was to investigate the potential of organosilicon compounds as modifiers of the mechanical and rheological properties of PLA, as well as to develop a new method for conducting mechanical property tests through innovative high-throughput technologies. Precise dosing methods were utilized to create PLA/silicone polymer blends with varying mass contents, allowing for continuous characterization of the produced blends. To automate bending tests and achieve comprehensive characterization of the blends, a self-created workstation setup has been used. The tensile properties of selected blend compositions were tested, and their ability to withstand dynamic loads was studied. The blends were characterized through various methods, including rheological (MFI), X-ray (XRD), spectroscopic (FTIR), and thermal properties analysis (TG, DSC, HDT), and they were evaluated using microscopic methods (MO, SEM) to examine their structures.