Abstract The flavonoids and xanthones present in the ethanol extracts of leaves and stems of Fridericia samydoides showed that anti-dengue activities in vitro were investigated qualitatively by liquid chromatography-ultraviolet-mass spectrometry in series. Nineteen flavones and fifteen xanthones were detected and characterized on the basis of their fragmentation pattern in the positive and negative ion mode tandem mass spectrometry spectra and ultraviolet bands. Acacetin, chrysin, vitexin, isovitexin, orientin, isoorientin, mangiferin, 2’-O-trans-caffeoylmangiferin, 2’-O-trans-coumaroylmangiferin and 2’-O-trans-cinnamoylmangiferin were identified by comparison with authentic samples. The other compounds detected were tentatively assigned by analysis of the spectral data and by comparison with literature reports. In addition, it performed the fractionation of the leaves extract leading to the isolation of mangiferin, isovitexin and isoorientin. All extracts and isolated compounds inhibited the Dengue virus replication cycle with EC50 less than 25.0 µg/mL for extracts and 272.5, 85.6 and 79.3 µg/mL for mangiferin, isovitexin and isoorientin, respectively.

Resumo A espécie Cissus erosa (Vitaceae) conhecida popularmente, no Brasil, como Cipó fogo é uma planta medicinal empregada no tratamento de verrugas e úlceras externas. O presente estudo objetivou a avaliação da atividade antiviral frente a Dengue e Zika virus dos extratos etanólicos de caules e de folhas desta espécie pelo método colorimétrico do MTT e determinar a caracterização fitoquímica por cromatografia líquida de ultra eficiência acoplada a espectrometria de massa destes extratos (CLUE-EM). Os extratos apresentaram atividade antiviral e baixa citotoxicidade. O extrato de folhas apresentou CC50 > 500 µg/ml para células LLCMK2 e CE50 = 18,2 µg/mL, IS > 27,5 contra o Dengue virus 2 (DENV 2). Ambos os extratos (caules e folhas) apresentaram atividade anti-Zika virus com CE50 de 45,8 µg/ml e 82,8 µg/ml, respectivamente. Os extratos apresentaram CC50 de 309,2 µg/ml (folhas) e 387,6 µg/ml (caules) para células Vero. Nas análises por CCD e CLAE-DAD detectou-se a presença de triterpenos, esteroides, flavonoides e taninos. Análises por CLUE-EM dos extratos permitiram a identificação parcial dos flavonoides majoritárias destes extratos como sendo, vitexina, isovitexina, orientina, isoorientina, luteolina-7,4’-di-O-glicosilflavona, metoxiluteolia-6(8)-C-hexosil. Os resultados dos estudos fitoquímicos até o momento sugerem que flavonoides e terpenoides são os constituintes majoritários dos extratos etanólicos destas espécies e devem contribuírem para a atividade antiviral observada in vitro.

Abstract Cissus erosa (Vitaceae), popularly known in Brazil as Cipó-fogo, is a medicinal plant used in the treatment of warts and external ulcers. The present study aimed to evaluate the activity of stems and leaves ethanol extracts of C. erosa against the Dengue and Zika virus by the MTT colorimetric method and to carry on the phytochemical characterization of active extracts by high performance liquid chromatography coupled to mass spectrometry (UPLC-MS). Only the leaves ethanol extract showed anti-Dengue virus activity EC50 18.2 µg/ml (SI > 27.5) and low cytotoxicity for LLCMK2 cells (CC50 > 500 mg/ml). Both extracts (stems and leaves) showed anti-Zika virus activity with EC50 of 45.8 mg/ml and 82.8 mg/ml, respectively. These extracts presented CC50 of 309.2 µg/ml (leaves) and 387.6 µg/ml (stems) to Vero cells. Analysis by CCD and HPLC-DAD detected the presence of triterpenes, steroids, flavonoids and tannins. UPLC-MS analyses of these extracts, allowed the identification of the majority of flavonoids present known as vitexin, isovitexin, orientin, isoorientin and two flavones derivatives, methoxyluteolin-6(8)-C-hexosyl and luteolin-7,4’-di-O-glycosylflavone. The results of the phytochemical studies here described suggest that flavonoids and terpenoids are the substances that contribute to the antiviral activity of the ethanol extracts within this species.