Antifeedant and ovicidal activities of a new cassane and other compounds from Caesalpinia welwitschiana Oliv. and Caesalpinia bonduc L. against Tuta absoluta (Lepidoptera: Gelechiidae)

Abstract

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.

Keywords:

• Cassanes
• flavonoides
• Tuta absoluta
• Antifeedant
• Oviposition
• Caesalpinia bonduc
• Caesalpinia welwitschiana

Data accessibility

The datasets supporting this article have been uploaded as part of the Electronic Supplementary Material.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

We gratefully acknowledge the financial support of the German Academic Exchange Service In-Region scholarship for funding FREE. SAM thanks the Federal Ministry of Cooperation and Development (BMZ), Germany for providing the financial support through ICIPE Tuta absoluta IPM project (N°: 12.1433.7-001.00). RJC acknowledges the DFG for funding for LCMS instrumentation (INST 187/621-1).