Isolation and chemical characterization of components from Azadirachta indica and Melia azedarach with biological activity

CABONI, P.; NTALLI, N.; BUENO, C.A.; ALCHÉ, L.E.

Emerging Trends in Dietary Components for Preventing and Combating Disease

American Chemical Society

Año: 2012; p. 51 - 77

In this chapter we review the biological activities of Azadirachta indica A. Juss (neem) (AI) and Melia azedarach L. (chinaberry) (MA), as well as the principle components this activity has been attributed to. We develop analytical methods for the structure elucidation and quantitation of the most abundant limonoids of AI and MA seeds and we report on their biological properties. The limonoids afforded by AI were azadirachtin A and B, nimbin, salannin and their acetyl derivatives; while MA afforded a new triterpenoid, named 3-alpha-tigloylmelianone, as well as three known limonoids named methyl kulonate, 21-beta-acetoxymelianone and melianone. The structures elucidation of the limonoids was performed by means of 1D and 2D-NMR and the accuracy of theoretical exact mass values, was deduced by the employment of HPLC-Q-TOF analysis. According to our results 21-beta-acetoxymelianone and 3-alpha-tigloylmelianone gather both antiproliferative (IC50 = 100 and 91.8 μg/ml) and cytotoxic (CC50 = 90.6 and 64.7 μg/ml) activities against the tumorigenic cell line A549, while melianone exhibited the highest cytotoxic activity with an CC50 calculated at 3.6 μg/ml. Methyl kulonate as well as limonoids isolated from AI were not found neither cytotoxic nor antiproliferative. In extends, MA fruits? methanol extract was analysed by GC/MS and was found to contain hexadecanoic, acetic, and hexanoic acids as well as furfural, 5- hydroxymethylfurfural. This extract was found nematicidal against Meloidogyne incognita, both in terms of juveniles paralysis (EC50/96h = 0.04 %) and biological cycle arrest (EC50 = 0.91 %), and the activity has been attributed to its contents in organic acids and aldehydes rather than its limonoids contents. A linear relationship of organic acids? C atom number and nematicidal activity was established at 31.2-500 μg/mL. Furfural exhibited the highest nematicidal activity both after nematodes immersion in test solutions and after exposure to its vapours (EC 50/1 day = 8.5 and 24.1 μg/mL, respectively).