Pest Management Science Pest Manag Sci 63:399–403 (2007) Toxicity of extracts and isobutyl amides from Piper tuberculatum: potent compounds with potential for the control of the velvetbean caterpillar, Anticarsia gemmatalis Hosana M Debonsi Navickiene, 1∗ Jos ´ e E Miranda, 2 S´ ergio A Bortoli, 3 Massuo J Kato, 4 Vanderlan S Bolzani 5 and Maysa Furlan 5 1 Faculdade de Ci ˆ encias Farmac ˆ euticas de Ribeir ˜ ao Preto, Universidade de S ˜ ao Paulo 14040903, Ribeir ˜ ao Preto-SP, Brazil 2 Setor de Entomologia, Embrapa Algod ˜ ao, R Osvaldo Cruz, 1143, 58107-720, Campina Grande-PB, Brazil 3 Faculdade de Ci ˆ encias Agr ´ arias e Veterin ´ arias, Universidade Estadual Paulista, 14884-900, Jaboticabal-SP, Brazil 4 Instituto de Qu´ ımica, Universidade de S ˜ ao Paulo, CP 26077, 05599-970, S ˜ ao Paulo-SP, Brazil 5 Instituto de Qu´ ımica, Universidade Estadual Paulista, CP 355, 14801-970, Araraquara-SP, Brazil Abstract: The isobutyl amides pellitorine (compound 1) and 4,5-dihydropiperlonguminine (compound 2) were extracted from the seeds of Piper tuberculatum Jacq. (Piperaceae) in yields of 6.10 and 4.45% respectively. The acute toxicities to the velvetbean caterpillar, Anticarsia gemmatalis (H ¨ ubner) (Lepidoptera: Noctuidae), of extracts of seeds, leaves and stems of P. tuberculatum, and of compounds 1 and 2, were evaluated by means of contact bioassays. The extracts caused 80% mortality when doses higher than 800.00 μg insect -1 of extract of seeds, leaves and stems were administered to the velvetbean caterpillars. Compounds 1 and 2 showed 100% mortality at doses of 200 and 700 μg insect -1 respectively. The LD 50 and LD 90 values were respectively 31.3 and 104.5 μg insect -1 for compound 1, and 122.3 and 381.0 μg insect -1 for compound 2. The potential value of extracts and amides derived from P. tuberculatum as efficient insecticides against velvetbean caterpillars is discussed.  2007 Society of Chemical Industry Keywords: Piper tuberculatum; Anticarsia gemmatalis; amides; insecticidal activity 1 INTRODUCTION Natural products with potential insecticidal activity have been considered as alternatives to conventional synthetic pesticides used in agriculture. Plant sec- ondary metabolites such as pyrethrins, rotenoids and limonoids have interesting ecological advantages, par- ticularly with respect to their specificity of action and their short lifetimes in the environment. 1,2 In spite of the large array of secondary compounds produced by Piperaceae species, only lignans and amides from these plants have demonstrated potential insecticidal activity to date. 3–9 The amides found in most species of the genus Piper have growth-reducing properties, insecticidal activity against Aedes atropalpus (Coq.) 10 and activity against fungi [Cladosporium cladosporioides (Fres.) de Vries and C. sphaerospermum Penz.]. 11 – 14 These amides also show antifeedant properties against the European corn borer Ostrinia nubilalis (H¨ ubner). 4,8,15 In addition to the damage caused by a number of other pests, the devastation occasioned by the vel- vetbean caterpillar, Anticarsia gemmatalis (H¨ ubner), to growing soybean plants is quite serious, leading to the complete defoliation of a plantation when severe attacks occur. 16 The use of synthetic chemical pesti- cides on a crop can be very costly for the farmer and can also produce environmental pollution. 17 An attrac- tive alternative solution to this problem is to employ natural products for control in agroecosystems, in the form of a preventive strategy against pest attack on agricultural products. The present research aims to determine the potential value of extracts and amides derived from Piper tuberculatum Jacq. as insecticides against velvetbean caterpillar A. gemmatalis. 2 MATERIALS AND METHODS 2.1 Instrumentation Melting points were determined on a Microquimica model APF-301 instrument. NMR spectra were acquired on a Bruker AC-200 spectrometer with deuterochloroform as solvent and tetramethylsilane (TMS) as reference. IR spectra were measured in potassium bromide discs on a Nicolet-730 FT- IR spectrophotometer, and UV absorption was recorded on a Hewlett Packard 8452 A diode array spectrophotometer. Electrospray mass spectral ∗ Correspondence to: Hosana M Debonsi Navickiene, Faculdade de Ci ˆ encias Farmac ˆ euticas de Ribeir ˜ ao Preto, Universidade de S ˜ ao Paulo 14040903, Ribeir ˜ ao Preto-SP, Brazil E-mail: hosana@fcfrp.usp.br (Received 12 May 2006; revised version received 31 October 2006; accepted 4 November 2006) Published online 26 February 2007; DOI: 10.1002/ps.1340  2007 Society of Chemical Industry. Pest Manag Sci 1526–498X/2007/$30.00