Anti-microbial screening and cytotoxic activity of aerial part of Thymelaea hirsuta L. essential oil growing in south-west Tunisia

This study aimed to investigate the antimicrobial and cytotoxic activities of essential oil isolated by the hydrodistillation of aerial parts of Thymelaea hirsuta. The antimicrobial activity of the oil was evaluated against eight bacterial and three fungal pathogenic strains. The results revealed that the essential oil exhibited a moderate-to-potent antimicrobial activity against all the microorganisms tested. Gram-positive bacteria were noted to be more sensitive to the oil than gram-negative bacteria and yeasts. In vitro cytotoxicity evaluation against HeLa cell lines showed that the essential oil exhibited moderate cytotoxicity on human tumor cells, with a high IC50 value of 175 micro g/mL. To the author's knowledge, this is the first study reporting on the antimicrobial and cytotoxic activities of Thymelaea hirsuta essential oil. Overall, the results indicate that the T. hirsuta essential oil has a number of attractive properties that might open new promising opportunities for the control or prevention of a wide range of microbial infections and cancers and can facilitate the use of essential oils as natural preservatives against spoilage microorganisms in food systems

Oxidative stress markers in intestinal mucosa of Tunisian inflammatory bowel disease patients

Inflammatory bowel diseases [IBDs], Crohn's disease [CrD] and ulcerative colitis [UC], are chronic gastrointestinal inflammatory disorders. The precise etiology of IBD remains unclear, and it is thought that interactions among various factors, including, genetic factors, the host immune system and environmental factors, cause disruption of intestinal homeostasis, leading to dysregulated inflammatory responses of the gut. As inflammation is intimately related to formation of reactive intermediates, including, reactive oxygen species, oxidative stress has been proposed as a mechanism underlying the pathophysiology of IBD. The purpose of this study is to examine the lipid peroxidation, protein oxidation and anti-oxidative profile in Tunisian IBD. Malondialdehyde [MDA], conjugated dienes [CD], protein thiol levels, as well as the catalase [CAT] activity were evaluated in intestinal biopsies of 17 patients affected by IBD [12 CrD and 5 UC] and 12 healthy control individuals. Oxidative stress was confirmed in these two types of disease biopsies as compared to controls. MDA and CD levels were significantly increased in both UC and CrD patients' biopsies as compared to controls' biopsies [P < 0.001]. CAT activity was similar in UC and CrD biopsies' and was not significantly increased in IBD patients' biopsies compared with controls' biopsies [P > 0.05]. A non-significant decrease in thiol [SH] level was observed in both UC and CrD patients' biopsies compared with controls' biopsies [P > 0.05]. Increased levels of MDA and CD in IBD patients' biopsies underline the implication of oxidative stress in the physiopathology of IBD