Azadirachtin B

Azadirachtin B is an azadirachtin that has been found in the neem tree, A. indica, and has diverse biological activities, including insecticidal, nematocidal, anticancer, and osteogenic properties.1,2,3,4,5 It has antifeedant activity against P. xylostella third instar larvae when used at a concentration of 3 mg/ml and induces mortality with an LC50 of 1.03 mg/ml.2 It induces mortality in M. incognita second instar larvae with an LD50 value of 125.8 ppm.3 Azadirachtin B (780 nmol in the drinking water) reduces the number of papillomas formed on mouse skin in a model of skin carcinogenesis induced by peroxynitrite and phorbol 12-myristate 13-acetate but is not cytotoxic to HL-60, A549, AZ521, SK-BR-3, or CRL1579 cancer cells (IC50s = >20 μM for all).4,5 It induces osteoblast differentiation and increases the rate of osteoblast proliferation in primary calvarial osteoblast cells when used at concentrations of 100 pM and 10 nM but not 1 pM, 1 μM, or 100 μM.1