Epoxidationof ferutinin by different fungi and antibacterial activity of its metabolite

Structural transformation of the sesquiterpene ester, ferutinin [1], by suspended fungal cultures of Aspergillus niger, Rhizopus stolonifer, and Fusarium lini, resulted in the formation of a metabolite. This metabolite was identified as ferutinin alpha-epoxide [2], by different spectroscopic techniques. Metabolite 2 showed a good antibacterial activity against Staphylococcus aureuscompared to ferutinin [1]

In vitro modulation of oxidative burst via release of reactive oxygen species from immune cells by extracts of selected tropical medicinal herbs and food plants

OBJECTIVE@#To evaluate in vitro immunomodulating properties and potential cytotoxicity of six tropical medicinal herbs and food plants namely Antidesma madagascariense (Euphorbiaceae) (AM), Erythroxylum macrocarpum (Erythroxylaceae) (EM), Faujasiopsis flexuosa (Asteraceae) (FF), Pittosporum senacia (Pittosporaceae) (PS), Momordica charantia (Cucurbitaceae) (MC) and Ocimum tenuiflorum (Lamiaceae) (OT).@*METHODS@#Initially, the crude water and methanol extracts were probed for their capacity to trigger immune cells' NADPH oxidase and MPO-dependent activities as measured by lucigenin- and luminol-amplified chemiluminescence, respectively; as compared to receptor-dependent (serum opsonised zymosan- OPZ) or receptor-independent phorbol myristerate acetate (PMA).@*RESULTS@#Preliminary screening on whole human blood oxidative burst activity showed significant and concentration-dependent immunomodulating properties of three plants AM, FF and OT. Further investigations of the fractions on isolated human polymorphonuclear cells (PMNs) and mice monocytes using two different pathways for activation of phagocytic oxidative burst showed that ethyl acetate fraction was the most potent extract. None of the active samples had cell-death effects on human PMNs, under the assay conditions as determined by the trypan-blue exclusion assay. Since PMA and OPZ NADPH oxidase complex is activated via different transduction pathways, these results suggest that AM, FF and OT does not affect a specific transductional pathway, but rather directly inhibit a final common biochemical target such as the NADPH oxidase enzyme and/or scavenges ROS.@*CONCLUSIONS@#Our findings suggest that some of these plants extracts/fractions were able to modulate significantly immune response of phagocytes and monocytes at different steps, emphasizing their potential as a source of new natural alternative immunomodulatory agents.

Myocardial ischaemia and reperfusion injury: reactive oxygen species and the role of neutrophil

A growing body of evidence suggests that oxygen radicals can mediate myocardial tissue injury during ischaemia and, in particular, during reperfusion. This review focuses on the role of neutrophil as a mediator of myocardial damage. Upon reperfusion, neutrophils accumulate and produce an inflammatory response in the myocardium that is responsible, in part, for the extension of tissue injury associated with reperfusion. It has shown that the inhibition of neutrophil accumulation and adhesion is associated with decreased infarct size. This strongly suggests that myocardial cells at risk region undergo irreversible changes upon reperfusion and accumulation of neutrophils. Several pharmacological agents [ibuprofen, allopurinol, prostacyclin, and prostaglandin E analogues] protect the myocardium from reperfusion injury. In addition, the mechanisms by which these agents act and directions of research that may lead to therapeutically useful approaches are also discussed in this review