1 2 In vitro activity of pineapple extracts (Ananas comosus, Bromeliaceae) 3 on Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) 4 Luciana Ferreira Domingues a Q1 , Rodrigo Giglioti a , Karina Alves Feitosa b , Rafaela Regina Fantatto b , 5 Márcio Dias Rabelo c , Márcia Cristina de Sena Oliveira c , Gilson Pereira de Oliveira a , 6 Ana Carolina de Souza Chagas c,⇑ 7 a Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista Júlio de Mesquita Filho, Via de Acesso Prof. Paulo Donato Castellane, s/n, CEP 14884-900, 8 Jaboticabal, São Paulo, Brazil 9 b Centro Universitário Central Paulista, Rua Pedro Bianchi, 111, Vila Alpes, São Carlos, São Paulo, Brazil 10 c Embrapa Pecuária Sudeste, Rodovia Washington Luiz, Km 234, CP 339, CEP 13560-970, São Carlos, São Paulo, Brazil 11 12 13 15 highlights 16 17  The activity of the Ananas comosus 18 extract and bromelain is evaluated on 19 R. (B.) microplus. 20  The extract presents LC 50 of 21 276 mg/mL and LC 90 of 8691 mg/mL 22 on engorged females. 23  Bromelain presents LC 50 of 373 mg/ 24 mL and LC 90 of 5172 mg/mL on 25 engorged females. 26  Neither of the substances tested have 27 efficacy on larvae. 28  This is the first reported investigation 29 of the A. comosus action on 30 R. (B.) microplus. 31 graphical abstract 33 33 35 article info 36 Article history: 37 Received 3 January 2013 38 Received in revised form 21 February 2013 39 Accepted 17 March 2013 40 Available online xxxx 41 Keywords: 42 Cattle tick 43 Botanical acaricides 44 Phytotherapy 45 Industrial residue 46 Waste 47 48 abstract 49 Measures to control the cattle tick, Rhipicephalus (Boophilus) microplus, based only on chemical products 50 are becoming unsustainable, mainly because of the development of resistance. The objective of this study 51 was to test the effect of the aqueous extract of pineapple skin (AEPS) and bromelain extracted from the 52 stem (Sigma–Aldrich Ò , B4882) on engorged females and larvae of R. (B.) microplus in vitro. These sub- 53 stances were diluted in water and evaluated at eight concentrations. Engorged females were collected 54 and distributed in groups of 10, with three repetitions for each treatment. After immersion in the solu- 55 tions, the females were placed in an incubator for observation of survival, oviposition and larval hatching. 56 The larval packet method was used, also with three repetitions with about 100 larvae each. The packets 57 were incubated and the readings were performed after 24 h. The estimated reproduction and efficacy of 58 the solutions were calculated. The LC 50 and LC 90 were estimated using the Probit procedure of the SAS 59 program. The eight concentrations were compared within each treatment by the Tukey test. For the 60 experiment with engorged females, the most effective concentrations were 125, 250 and 500 mg/mL: 61 33%, 48% and 59% for the AEPS and 27%, 51% and 55% for the bromelain. The LC 50 and LC 90 values were, 62 respectively, 276 and 8691 mg/mL for AEPS and 373 and 5172 mg/mL for bromelain. None of the dilu- 63 tions tested was effective against the larvae of R.(B.) microplus. This is the first report of the action of 64 pineapple extracts or their constituents on cattle ticks. The results demonstrate that further studies 65 regarding composition of tick cuticle, with evaluation of other solvents and formulations, should be con- 66 ducted seeking to enhance the effect of pineapple extracts and compounds against this ectoparasite. 67 Ó 2013 Published by Elsevier Inc. 68 69 0014-4894/$ - see front matter Ó 2013 Published by Elsevier Inc. http://dx.doi.org/10.1016/j.exppara.2013.03.021 ⇑ Corresponding author. Fax: +55 16 3361 5754. E-mail address: carolina.chagas@embrapa.br (A.C.de Souza Chagas). Experimental Parasitology xxx (2013) xxx–xxx Contents lists available at SciVerse ScienceDirect Experimental Parasitology journal homepage: www.elsevier.com/locate/yexpr YEXPR 6648 No. of Pages 5, Model 5G 1 April 2013 Please cite this article in press as: Domingues, L.F., et al. In vitro activity of pineapple extracts (Ananas comosus, Bromeliaceae) on Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). Exp. Parasitol. (2013), http://dx.doi.org/10.1016/j.exppara.2013.03.021