Croton cordiifolius is widely used in Brazilian Caatinga folk medicine to treat general inflammation, pain, and gastrointestinal disturbances. Currently, its medicinal properties are not well understood, owing to the absence of chemical and pharmacological studies. The aims of this work were to analyze the chemical composition of C. cordiifolius stem bark and evaluate its in vitro antioxidant and in vivo anti-inflammatory activities. C. cordiifolius ethanolic extract (CcEE) was obtained by maceration, while essential oil (CcEO) was extracted by hydrodistillation in a Clevenger-type apparatus. The chemical composition was evaluated by thin-layer chromatography and GCMS. Total phenolics, flavonoids, and antioxidant activity were quantitated by spectrophotometry. Topical anti-inflammatory activity was evaluated by different ear edema models in mice. The major compounds in CcEO were α-pinene (51.76%) and β-pinene (19.08%). CcEE analysis indicated the presence of alkaloids, mono-and sesquiterpenes, flavonoids, phenylpropanoids, triterpenes, steroids, and coumarins. CcEE showed antioxidant activity in vitro. In a topical anti-inflammatory assay, CcEO showed no activity. On the contrary, CcEE inhibited ear edema induced by phorbol 12-myristate 13-acetate (PMA), arachidonic acid (AA), ethyl phenylpropriolate (EPP), and phenol. Probable mechanisms include inhibition of AA metabolite biosynthesis, vasoactive amine activity, and cytokine release/activity. These results corroborate the popular reputation of C. cordiifolius as an anti-inflammatory remedy.
Aims
Antimicrobial resistance is one of the highest priorities in global public health with Staphylococcus aureus among the most important microorganisms due to its rapidly evolving antimicrobial resistance. Despite all the efforts of antimicrobial stewardship, research and development of new antimicrobials are still imperative. The thiazolidine ring is considered a privileged structure for the development of new antimicrobials. This study aimed to compare the antibacterial effects of two analogue series of thiazolidine‐2,4‐dione and 4‐thioxo‐thiazolidin‐2‐one against multidrug‐resistant Staph. aureus clinical isolates.
Methods and Results
The derivatives 1a, 2a and 2b exhibited MIC between 1–32 μg ml−1, with time‐to‐kill curves showing a bactericidal effect up to 24 h. In the antibiofilm assay, the most active derivatives were able to inhibit about 90% of biofilm formation. The 4‐thioxo‐thiazolidine‐2‐one derivatives were more active against planktonic cells, while the thiazolidine‐2,4‐dione derivatives were able to disrupt about 50% of the preformed biofilm. In the in vivo infection model using Caenorhabditis elegans as a host, the derivatives 1a, 2a and 2b increased nematode survival with a concentration‐dependent effect. Exposure of Staph. aureus to the derivatives 2a and 2b induced surface changes and decrease cell size. None of the derivatives was cytotoxic for human peripheral blood mononuclear cells (PBMC) but showed moderate cytotoxicity for L929 fibroblasts.
Conclusion
The 5‐(3,4‐dichlorobenzylidene)‐4‐thioxothiazolidin‐2‐one (2b) was the most active derivative against Staph. aureus and showed higher selective indices.
Significance and Impact of the Study
4‐thioxo‐thiazolidin‐2‐one is a promising scaffold for the research and development of new antimicrobial drugs against multidrug‐resistant Staph. aureus.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.