Volatile composition and biological activity of key lime Citrus aurantifolia essential oil.

The essential oil of Citrus aurantifolia (Christm) Swingle fruits (limes) was studied for its potential spasmolytic effects in relation to its chemical composition. The essential oil, extracted by hydrodistillation (HD), was analyzed by GC-FID and GC-MS. The antispasmodic activity was evaluated on isolated rabbit jejunum, aorta and uterus. The results indicated that the essential oil of C. aurantifolia possesses important spasmolytic properties, which are likely to be due to its major constituents, limonene (58.4%), beta-pinene (15.4%), gamma-terpinene (8.5%), and citral (4.4%).

Rhodiola rosea extract protects human cortical neurons against glutamate and hydrogen peroxide-induced cell death through reduction in the accumulation of intracellular calcium.

The aim of this study was to investigate the neuroprotective effects of a titolated extract from Rhodiola rosea L. (RrE) and of salidroside (Sa), one of the major biologically active compounds extracted from this medicinal plant, against oxidative stressor hydrogen peroxide (H2O2) and glutamate (GLU)-induced cell apoptosis in a human cortical cell line (HCN 1-A) maintained in culture. The results obtained indicate that exposure of differentiated HCN 1-A neurons to GLU or H2O2 resulted in concentration-dependent cell death. A 24 h pre-treatment with RrE significantly increased cell survival and significantly prevented the plasma membrane damage and the morphological disruption caused by GLU or H2O2, indicating that neurons treated with RrE were protected from the neurotoxicity induced by the oxidative stressor used. In addition, RrE significantly reduced H2O2 or GLU-induced elevation of intracellular free Ca²âº concentration. The results obtained have also shown that Sa caused similar effects in all experimental models used; however, the potency of the action was lower than that of the extract containing corresponding quantities of Sa. These findings indicate that RrE has a neuroprotective effect in cortical neurons and suggest that the antioxidant activity of the RrE, due to the structural features of the synergic active principles they contain, may be responsible for its ability to stabilize cellular Ca²âº homeostasis.