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Twenty-two compounds were isolated from the fruit of Albizia lebbeck including one unprecedented, rare amino acid-derived zwitterionic and one new flavone derivative. The isolation was performed on repeated column chromatography over silica gel and their structures were determined by 1D-, 2D-NMR and HR-ESI-MS spectra together with reported data in the literature. The chemophenetic significance is also discussed. Some isolated compounds were reported for the first time to be found in the species. Additionally, compound 2 showed antibacterial activity and compounds 1 and 2 revealed moderate cytotoxic activity against the Raw 264.7 cancer cell line with IC 50 values of 37.19 µM and 29.36 µM, respectively. Furthermore, a proposed biosynthetic pathway of compound 1 is described.

Methanolic extracts of liana of Caesalpinia welwitschiana and leaves of C. bonduc were found to possess moderate antifeedant and ovicidal activities against Tuta absoluta . Bioassay-guided isolation of constituents from the most active fraction of C. welwitschiana led to the identification of four known compounds [isobonducellin 1a and bonducellin 1 b , intricatinol 2 , (-)-epigallocatechin-3- O -gallate 4 ] and one new constituent [welwitschianic acid 3 ]. The most active fraction of C. bonduc afforded two known constituents neocaesalpin L 5 and neocaesalpin A 6 . The isolated structures were elucidated on the basis of their MS, UV, IR and 1 & 2 D NMR spectra and by comparison with literature data. Compounds 2 , 4 - 6 were showed antifeedant and ovicidal properties against T. absoluta, some comparable to that of azadirachtin at 50, 100 and 200 ng/µl. Overall, the present study, conclude that the two species of the plant could be a promising source of eco-friendly botanical constituents.

Tuta absoluta Meyrick originates in South America and is now one of the most important insect pests of Solanaceae in different parts of the world, including Africa. Its control has relied primarily on chemical insecticides, which are associated with negative ecological effects. In the present study, essential oils of Ocimum gratissimum and O. kilimandscharicum were tested for repellence and fumigant toxicity on the adult stages under laboratory conditions. The oil of O. gratissimum was more repellent, but its toxicity was comparable with that of O. kilimandscharicum. The major constituents of O. gratissimum were methyl eugenol (39.5%) and eugenol (29.7%). Those of O. kilimandscharicum were camphor (47.1%) and 1.8-cineole (19.3%). Eugenol (LC 50 of 0.24 μl/ml, 83.3%, RI 50  = 0.15) and camphor (LC 50 of 0.23 μl/ml, 89.5%, RI 50  = 0.13) were more toxic (at 1 μl/ml for 24 h) and repellent than the other constituents. The results show potential of the essential oils for use in integrated management of the tomato pest.