Application of "magnetic tongue" to the sensory evaluation of extra virgin olive oil.

The perception of odour and flavour of foods is a complicated physiological and psychological process that cannot be explained by simple models. Unfortunately, taste is not objective, but partially subjective and it depends also on the mood of the taster. Generally, sensory analysis is used to describe sensory features. The availability of a number of instrumental techniques has opened up the possibility to calibrate the sensory perception. Here we have tested the potentiality of nuclear magnetic resonance spectroscopy as "magnetic tongue" to measure sensory descriptors in extra-virgin olive oil. We were able to correlate the NMR metabolomic fingerprints of extra-virgin olive oil to the sensory descriptors: tomato, bitter, pungent, rosemary, artichoke, sweet, grassy and leaf.

A more detailed picture of the interactions between virtual screening-derived hits and the DNA G-quadruplex: NMR, molecular modelling and ITC studies.

The growing amount of literature about G-quadruplex DNA clearly demonstrates that such a structure is no longer viewed as just a biophysical strangeness but it is instead being considered as an important target for the treatment of various human disorders such as cancers or venous thrombosis. In this scenario, with the aim of finding brand new molecular scaffolds able to interact with the groove of the DNA quadruplex [d(TGGGGT)](4), we recently performed a successful structure-based virtual screening (VS) campaign. As a result, six molecules were found to be somehow groove binders. Herein, we report the results of novel NMR titration experiments of these VS-derived ligands with modified quadruplexes, namely [d(TGG(Br)GGT)](4) and [d(TGGGG(Br)T)](4). The novel NMR spectroscopy experiments combined with molecular modelling studies, allow for a more detailed picture of the interaction between each binder and the quadruplex DNA. Noteworthy, isothermal titration calorimetry (ITC) measurements on the above-mentioned compounds revealed that 2, 4, and 6 besides their relatively small dimensions bind the DNA quadruplex [d(TGGGGT)](4) with higher affinity than distamycin A, to the best of our knowledge, the most potent groove binder identified thus far.