Saponins from the roots of Chiococca alba and their in vitro anti-inflammatory activity Ricardo Moreira Borges a, *, Samuel Santos Valenc ¸a b , Alan Aguiar Lopes b , Nancy dos Santos Barbi c , Antonio Jorge Ribeiro da Silva a a Nu ´cleo de Pesquisas de Produtos Naturais, Centro de Cieˆncias da Sau ´de-Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, RJ, Brazil b Instituto de Cieˆncias Biome ´dicas, Centro de Cieˆncias da Sau ´de-Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, RJ, Brazil c Departamento de Ana ´lises Clı´nicas e Toxicolo ´gicas, Faculdade de Farma ´cia, Centro de Cieˆncias da Sau ´de-Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, RJ, Brazil 1. Introduction Chiococca alba (L.) Hitchc. (Rubiaceae) is a tropical and sub- tropical shrub spread all over the American continent. The infusion of its roots have been used in Brazilian traditional medicine for the treatment of several illnesses due to its anti-rheumatic, diuretic, anti-inflammatory, anti-viral, anti-snakebite activity (Mors et al., 2000) and for the cure of intermittent fever (Cruz, 1930). ‘‘Cainca’’ (as it is commonly known in Brazil) has been listed in the first Brazilian Pharmacopeia as well as in several European pharma- copeias (Schapoval et al., 1983). An herbal remedy prescribed for rheumatism containing the ethanolic extract of C. alba roots along with an extract of Polypodium lepidopteris has been in the Brazilian pharmaceutical market until the nineties. Lignans, coumarins, ketoalcohols (El-Hafiz et al., 1991), triterpenes and a glucuronide glycoside together with two other compounds identified as artifacts of the isolation procedure (Bhattacharyya and Cunha, 1992; Bhattacharyya et al., 2008), iridoids (Carbonezi et al., 1999), a nor-seco-pimarane (Borges-Arga ´ ez et al., 2001), two quinoline alkaloids (El-Abbadi et al., 1989) and flavonoids (Lopes et al., 2004) have been reported as phytochemical constituents of C. alba. Two major saponins have been isolated from the roots of C. alba and their structures elucidated as two bisdesmosidic saponins with a 3b-hydroxyo- lean-12,15-dien-28-oic acid aglicone coupled to 4 and 5 saccharide residues, respectively, at positions 3 and 28 (Borges et al., 2009). Previous pharmacological studies on C. alba have revealed anti- inflammatory effects (Schapoval et al., 1983), antimicrobial action against Staphylococcus aureus (Borges-Arga ´ez et al., 1997) as well as mild anticancer activity (Carbonezi et al., 1999). The ethanol extract from the roots of C. alba has been submitted to the Salmonella assay and did not display mutagenicity (Gazda et al., 2006). The authors have also reported that acute and subacute oral toxicity of the C. alba roots ethanolic extract are very low. We have published recently the results of our studies on the application of these saponins as adjuvants in formulations with the FML antigen for mice prophylaxis against visceral leishmaniasis (Nico et al., 2012). Earlier studies with the root-bark of this plant had indicated the occurrence of an acidic bioactive ‘substance’ (Cruz, 1930) named ‘caincic acid’ (renamed ‘caincin’). Clinical tests with this fraction have showed significant potential as a powerful tonic, to increase urine secretion and as a slightly purgative. This bioactive ‘substance’ was afterwards recognized as a complex mixture of saponins in 1850 by Rockleder and Hlasiwetz (Cruz, 1930). Phytochemistry Letters 6 (2013) 96–100 A R T I C L E I N F O Article history: Received 2 July 2012 Received in revised form 1 October 2012 Accepted 9 November 2012 Available online 21 December 2012 Keywords: Chiococca alba Rubiaceae Saponin Inflammation A B S T R A C T Five triterpenoidal saponins were isolated from the roots of Chiococca alba (L.) Hitchc. (Rubiaceae). Two of the saponins, chiococcasaponin III (3-O-b-D-glucopyranurosyl-3b-hydroxyolean-12,15-dien-28-oic acid 28-O-b-D-xylopyranosyl (1 ! 4)-a-L-rhamnopyranosyl (1 ! 2)-a-L-arabinopyranosyl ester) and chiococcasaponin IV (3-O-b-D-glucopyranurosyl-3b-hydroxyolean-12,15-dien-28-oic acid 28-O-a-L- rhamnopyranosyl (1 ! 2)-a-L-arabinopyranosyl ester) were new and their structures were elucidated on the basis of extensive application of NMR techniques and high resolution electrospray mass spectrometry together with acid hydrolysis product analysis. As part of our investigations on the chemical profile and pharmacological activity of the roots of C. alba, we report the results of the evaluation of the activity of the saponin fractions against in vitro lipopolysaccharide-induced inflammation. The results found, strongly support the fractions I, III and IV as having anti-inflammatory properties. ß 2012 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved. * Corresponding author at: Avenida Brigadeiro Trompowsky s/n, CCS, Bloco H, Ilha do Funda ˜o, 21941-590 Rio de Janeiro, RJ, Brazil. Tel.: +55 21 25626791; fax: +55 21 22702683. E-mail address: ricardo_mborges@nppn.ufrj.br (R.M. Borges). Contents lists available at SciVerse ScienceDirect Phytochemistry Letters jo u rn al h om ep ag e: ww w.els evier.c o m/lo c ate/p hyt ol 1874-3900/$ – see front matter ß 2012 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.phytol.2012.11.006