Search

Abstract Introduction The objective of this study is to investigate the shear bonding strength of a glycoalkaloid, also a novel matrix metalloproteinase enzyme known as α-tomatine, on two different surfaces of dentin (sound & caries-affected) and its efficacy against cariogenic microorganisms using in vitro and in silico methods. Methods The effect of a-tomatine at different concentrations (0.75 / 1 / 1.5 µM) on shear bonding strength in caries-affected and sound dentin was also investigated (n = 10; each per subgroup). The analysis of shear bonding and failure tests was conducted after a 24-hour storage period. Fracture surfaces were examined under a scanning electron microscope. A stock solution 3 mM of a-tomatine was prepared for antimicrobial evaluation. Antimicrobial activities of the agents against Streptococcus mutans ATCC 25175, Lactobacillus casei ATCC 4646, and Candida albicans ATCC 10231 standard strains were investigated by microdilution method. In addition, through the method of molecular docking and dynamic analysis, the affinity of a-tomatine for certain enzymes of these microorganisms was examined. Results The pretreatment agent and dentin type significantly influenced shear bonding strength values (p

IntroductionCubeb, Piper cubeba L., has been used for centuries in traditional medicine and culinary practices, with a wide range of biological and pharmacological activities.ObjectiveHerein, we determined the phytochemical profile, mineral, fatty acids, and amino acid contents of P. cubeba berries and assessed the dermacosmeceutical properties of their water extract and essential oil (EO). These included assessing their antioxidant and antibacterial activities as well as their in vitro inhibitory activities against tyrosinase and elastase enzymes. In addition, molecular docking and molecular dynamics studies were performed on the major identified compounds of the EO.Results and discussionA total of forty-three compounds belonging to organic acids, phenolic acids and flavonoids were found in the water extract, while 36 volatile compounds were identified in the EO with Z-isoeugenol, dihydroeugenol, β-pinene, E-caryophyllene, and 1,8-cineole as major constituents. The berries were found to be rich in sodium and iron, have moderate zinc content along with low contents of total nitrogen, phosphorus, and potassium. Amino acid analysis revealed a considerable concentration of isoleucine and phenylalanine, whereas 11,14,17-eicosatrienoic acid and linoleic acid were identified as the major fatty acids. In the DPPH and FRAP assays, the water extract elicited considerable antioxidant activity compared to the reference compounds. Enzyme inhibitory assays revealed that the EO had a potential to inhibit tyrosinase and elastase enzymes with IC50 values of 340.56 and 86.04 μg/mL, respectively. The water extract and EO completely inhibited the bacterial growth at MIC of 50 mg/mL and 20%, respectively. At sub-MIC concentrations, the extract and the EO substantially reduced the biofilm formation by up to 26.63 and 77.77%, respectively, as well as the swimming and swarming motilities in a dose-dependent manner. Molecular docking and molecular dynamics showed that the five main components of P. cubeba EO could be the major contributors to the elastase and tyrosinase inhibitory effect.ConclusionThis study emphasizes the promising potential of P. cubeba as a valuable source of natural compounds that can be utilized for the development of innovative pharmaceuticals, dietary supplements, and dermacosmeceutical agents.

The phytoconstituents of the aqueous extract from Syzygium jambos L. (Alston) leaves were defined using HPLC-PDA-MS/MS and the antioxidant, anti-aging, antibacterial, and anti-biofilm activities of the extract were in silico and in vitro investigated. The antioxidant activities were performed using in vitro DPPH and FRAP assays as well as H2-DCFDA assay in HaCaT cells in which oxidative stress was induced by UVA radiation. Anti-aging activity was tested in vitro, using aging-related enzymes. The antibacterial, anti-biofilm and inhibitory effects on bacterial mobilities (swarming and swimming) were assessed against Pseudomonas aeruginosa. Results showed that S. jambos aqueous extract contained 28 phytochemicals belonging to different metabolite classes, mainly phenolic acids, gallic acid derivatives, flavonoids, and ellagitannins. Mineral content analysis showed that S. jambos leaves contained moderate amounts of nitrogen, potassium, manganese, magnesium, and zinc, relatively low amounts of phosphorus and copper, and high concentration of calcium and iron. The extract displayed strong antioxidant activities in vitro and inhibited UVA-induced oxidative stress in HaCaT cells. Docking the major compounds identified in the extract into the four main protein targets involved in skin aging revealed an appreciable inhibitory potential of these compounds against tyrosinase, elastase, hyaluronidase, and collagenase enzymes. Moreover, molecular dynamic simulations were adopted to confirm the binding affinity of some selected compounds towards the target enzymes. The extract exhibited pronounced in vitro anti-aging effects, compared to kojic acid and quercetin (the reference compounds). It also inhibited the growth of P. aeruginosa, counteracted its ability to form biofilm, and impeded its swarming and swimming mobilities. Altogether, these findings strongly propose S. jambos leaves as a promising source of bioactive metabolites for the development of natural cosmeceutical and dermatological agents.

Plant extracts and their individual components have been used to manage skin aging for several decades. Recently, the discovery of new natural bioactive agents, that not only enhance the skin health but also offer protection against various deleterious factors, such as free radicals, ultraviolet radiation, and microbial infections, has been a potential target by many researchers. The aim of the current work was to investigate the phytochemical profile of an ethanol bark extract from Pseudobombax ellipticum, and to evaluate its antioxidant, antiaging and antibacterial activities in vitro. Molecular docking and molecular dynamics studies were adopted to estimate and confirm the binding affinity of several compounds and explain their binding pattern at the binding sites of four target enzymes associated with skin aging, namely collagenase, elastase, tyrosinase, and hyaluronidase. HPLC-MS/MS analysis led to the tentative identification of 35 compounds comprising phenolic acids, and their glycosides, procyanidins and flavonoid glycosides. The extract demonstrated a promising in vitro antioxidant activity in the DPPH and FRAP assays (IC50 56.45 and 15.34 μg/mL, respectively), and was able to inhibit the aforementioned key enzymes with comparable results to the reference drugs. In addition, the extract (6.25 mg/mL) inhibited the biofilm production of Pseudomonas aeruginosa and diminished the swimming and swarming motilities. The docked compounds revealed appreciable binding energy with the tested enzymes and were stable throughout the molecular dynamic simulations. In view of this data, P. ellipticum bark can be regarded as a good candidate for prospective application in derma-cosmeceutical preparations.

This study aims to examine the effect of a-tomatine, a new matrix metalloproteinase inhibitor for dentistry, as a surface pretreatment on the bonding strength of different types of dentine via in vitro and in silico methods. The binding efficacy of both a-tomatine and chlorhexidine to MMP-2, 8, and 9 was evaluated through molecular docking and dynamics analyses. For microtensile testing (µTBS), specimens (n = 84) were categorized into two groups based on the type of dentin: sound (SD) and eroded (ED) (n = 42). Each group was further divided into three subgroups according to the utilization of surface pretreatment agents (1.5 µM of tomatine, 2% chlorhexidine (CHX), and the control). Composite buildups were gradually created via a three-step etch-and-rinse technique. The specimens were sectioned into sticks and subsequently subjected to µTBS after aging for either 24 h (n = 7) or 6 months (n = 7). The data were subjected to analysis using two-way ANOVA with a Bonferroni correction post hoc test. The significance level was evaluated at a minimum of p < 0.05. According to molecular docking and dynamic simulation analyses, a-tomatine exhibits a higher affinity for MMP-2, -8, and -9 enzymes compared to chlorhexidine. Lower µTBS values were observed in all ED groups compared to the SD groups. Following 24-h aging, the CHX application in both the SD and ED groups achieved lower µTBS values compared to the control group (p < 0.01 and p > 0.05, respectively). The most favorable results were consistently achieved across all the subgroups subjected to a-tomatine applications (p < 0.05). a-tomatine is a more effective MMP inhibitor than chlorhexidine in terms of preserving bond strength values over time and its capacity to bind to MMP-2,8, and 9 for inhibition.