ORIGINAL PAPER Methanol extract from mycelium of endophytic fungus Rhizoctonia sp. induces antinociceptive and anti-inflammatory activities in mice Betijane Soares de Barros • Juliane Pereira da Silva • Jamylle Nunes de Souza Ferro • Isabela Karine Rodrigues Agra • Fabı ´ola de Almeida Brito • E ´ rica Dutra Albuquerque • Luiz Carlos Caetano • Emiliano Barreto Received: 2 February 2011 / Accepted: 17 March 2011 / Published online: 6 April 2011 Ó The Japanese Society of Pharmacognosy and Springer 2011 Abstract The present study aimed to elucidate the antin- ociceptive and anti-inflammatory properties of the methanol extract from the mycelium of the endophytic fungus Rhi- zoctonia sp. (MEMRh) in mice. The antinociceptive activity was assessed using the abdominal constriction, hot plate, and formalin tests. The anti-inflammatory activity was assessed using a murine model of paw edema. Intraperito- neal administration of MEMRh (0.1, 1, 10 and 100 mg/kg, i.p.) produced an inhibition of acetic acid-induced writhing in mice for at least 8 h. In addition, all doses tested of the methanol extract were able to prevent thermal nociception in the hot-plate test. Furthermore, treatment with MEMRh (10 mg/kg, i.p.) inhibited both the early and late phases of formalin-induced nociception. This antinociceptive effect exhibited by MEMRh in the formalin test was reversed by the systemic administration of naloxone. MEMRh produced inhibition in a carrageenan-induced edema model at a dose of 10 mg/kg. The same extract also displayed significant activity against a histamine- or PGE 2 -induced edema model. The experimental data demonstrated that MEMRh showed remarkable anti-inflammatory and antinociceptive activi- ties. Further studies are warranted to define and isolate the active anti-inflammatory and antinociceptive components from this endophytic fungus, which may yield effective agents for the treatment of inflammatory disorders. Keywords Endophytes Á Rhizoctonia sp. Á Analgesic Á Anti-inflammatory Introduction The presence of endophytes brings many advantages to the host plant, including the ability to produce antibiotics and other secondary metabolites of pharmacological interest and use as biological control agents [1]. The prospect that endophytes produce novel bioactive products stems from the idea that some endophytes may have coevolved with their respective higher plant, and as a result may produce certain metabolites characteristic of their hosts [2]. On the other hand, endophytes may produce useful compounds unique to them [3]. The discovery that an endophytic fungus (Taxomyces andreanae) also produced the anticancer drug paclitaxel (Taxol Ò ) derived from Pacific yew (Taxus brevifolia) was unexpected [4]. Moreover, several studies indicate that endophytic fungi isolated from medicinal plants have the ability to produce secondary metabolites of interest against cancer, sepsis and malaria [5–7]. Thus, these observations stimulated the opening of a fascinating area of research in microbiology where there is only fragmented information on endophytes. Studies on endophytic fungi are therefore of great value to ecology and pharmacology. For instance, the mycelia of fungi of the genus Rhizoctonia are able to produce a large series of secondary metabolites with interesting biological activities, such as the three dioxo- piperazines [8], and phenylacetic acid and derivatives are found in the culture filtrate of R. solani [9] and the two B. S. de Barros Á J. P. da Silva Á J. N. de Souza Ferro Á I. K. R. Agra Á F. de Almeida Brito Á E. Barreto (&) Laborato ´rio de Biologia Celular, Nu ´cleo de Pesquisa Multidisciplinar, Instituto de Cie ˆncias Biolo ´gicas e da Sau ´de, Campus A.C. Simo ˜es, s/n. Tabuleiro dos Martins, Maceio ´, Alagoas 57072-970, Brazil e-mail: emilianobarreto@optma.org E ´ . D. Albuquerque Á L. C. Caetano Laborato ´rio de Biotecnologia de Plantas e Microrganismos Endofı ´ticos, Instituto de Quı ´mica e Biotecnologia, Universidade Federal de Alagoas, Maceio ´-AL, Brazil 123 J Nat Med (2011) 65:526–531 DOI 10.1007/s11418-011-0534-x