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In order to investigate its insecticide potential, the neem cake methanol extract was first analyzed and then separated by different solvents. The high-performance liquid chromatography analysis showed that the neem cake methanol extract still contained relevant quantities of nortriterpenes. Fractions of increasing polarity were obtained from the separation process: hexane fraction (Hp), EtOAc fraction (Ep), n-BuOH fraction (Bp), and aqueous fraction (Wp). The activity of the fractions on Aedes albopictus (Skuse) eggs and larvae was tested, and the Ep fraction exhibits the most relevant larvicide effect. The nuclear magnetic resonance fingerprint analysis of this phytocomplex isolated on EtOAc fraction was performed. The larvicidal effectiveness of the phytocomplex isolated on EtOAc, compared to that of pure and commercial azadirachtin solutions of different concentrations, was checked. The results showed that the activity of the phytocomplex, as a whole, was significantly higher than those of isolated compound solutions. As a consequence, the neem cake is a promising low-cost, easily available on the market, and natural resource to develop a new bioinsecticide, mainly in developing countries.

Propolis is a beehive product popular in natural medicine thanks to its noteworthy properties. Propolis is non-toxic but is responsible for allergic reactions in sensitive individuals. In this paper, we propose a new gas chromatography-mass spectrometry (GC-MS) analytical methodology for the quantitative analysis of two allergenic esters in propolis specimens, benzyl salicylate and benzyl cinnamate, and test it on specimens from different locations of central Italy. We also present the results obtained in the chemical characterization of the same specimens. The characterization showed that the resin fractions of all of the specimens are of poplar origin.

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