"Gold" Pressed Essential Oil: An Essay on the Volatile Fragment from Citrus Juice Industry By-Products Chemistry and Bioactivity.

Present essay explores the potentials of Citrus juice industry's by-products as alternative bioactive natural products resources. Four crude Cold Pressed Essential Oils (CPEOs), derived from orange, lemon, grapefruit, and mandarin, were studied. All CPEOs were subjected to water distillation, in order to obtain the volatile fragment, which was further fractionated with respect to distillation period in two parts, concluding to eight samples. These samples along with the four original CPEOs were assessed in relation to their phytochemical content and their repellent and larvicidal properties against Asian Tiger Mosquito. The volatiles recovery rates ranged from 74% to 88% of the CPEO. Limonene presented a significant increase in all samples ranging from 8% to 52% of the respective CPEO's content and peaked in mandarin's 2nd volatile fragment which comprised 97% of the essential oil. The refinement process presented clear impacts on both bioassays: a significant increase in larvicidal potency was observed, annotated best by the improvement by 1100% and 1300% of the grapefruit volatile fractions; repellence testing provided only one significant result, the decrease of landings by 50% as a response to mandarin's second volatile fraction. The applied methodology thus may be considered for the improvement of Citrus juice industry's by-products chemistry and bioactivity.

Antiangiogenic potential of grape stem extract through inhibition of vascular endothelial growth factor expression.

The aim of the present study was to investigate the antiangiogenic potential of a grape stem extract against tube formation by human endothelial cells (EA.hy926). The results showed that at low and non-cytotoxic concentrations (50 and 100 µg/ml) the grape stem extract inhibited tube formation, indicating a possible antiangiogenic activity. Moreover, the results showed that this extract inhibited the expression levels of vascular endothelial growth factor (VEGF), one of the most potent proangiogenic factors, suggesting that the tube formation inhibition by the extract may be exerted through inhibition of VEGF levels. Since it is well established that VEGF prevents apoptosis, the previous finding was further supported by the fact that the grape stem extract induced apoptosis in EA.hy926 cells. Furthermore, it was shown that the extract treatment did not change the levels of the proangiogenic molecules hypoxia inducible factor 1 alpha (HIF-1α) and cyclooxygenase-1 (COX-1). Therefore, these findings indicate that the grape stem extract reduces VEGF levels through mechanisms that may be HIF-1α- and COX-1-independent. The present study is the first showing that grape stem extracts possess antiangiogenic potential. Thus, our findings suggest that since grape stem extracts possess important bioactivities such as antiangiogenic potential, they could be exploited for developing chemopreventive and anticancer agents, while simultaneously protecting the environment through the use of a harmful waste.