Antiherpetic activity of a flavonoid fraction from Ocotea notata leaves

Abstract

This study describes the isolation of a flavonoid fraction from leaves of Ocotea notata (Nees & Mart.) [10]) present in the fraction and its activity against the Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). The 50% effective concentrations values (EC50) calculated from the dose-response curve and the selectivity indices (SI) against the virus were: EC50 35.8 µg/mL and SI 5.5 to HSV-1 and EC50 23.5 µg/mL and SI 8.5 to HSV-2. The flavonoid fraction was more active against HSV-2 than HSV-1. The mechanisms of antiviral action of the flavonoid fraction against the virus were also evaluated. The percentage inhibition (PI) obtained for HSV-2 was higher than 90% in the following assays: virucidal, pre-treatment of cells, treatment of cells after viral adsorption and treatment of cells after viral penetration. For HSV-1, the flavonoid fraction had no effect in pretreatment of cells and showed 60% of inhibition in virucidal assay.

<b>An anti-dengue and anti-herpetic polysulfated fraction isolated from the coenocytic green seaweed <i>Caulerpa cupressoides</i> inhibits thrombin generation in vitro

“…The 50% cytotoxic concentration (CC 50 ) was calculated as the dilution that caused a reduction of 50% in the number of viable cells (Vanderlei et al, 2016). The antiviral effect of Cc-SP1 and acyclovir was evaluated by the titer reduction (Garrett et al, 2012). The virus titers were calculated using the Reed and Muench statistical method and expressed as 50% tissue culture infective dose (TCID 50 ) per mL.…”

“…No in situ cytotoxic effects on cell viability were detected with Cc-SP1 at CC 50 up to 1000 μg mL -1 for cultured cells, suggesting biocompatibility in vitro (Vanderlei et al, 2016). In addition, no microscopically visible change of normal cellular morphology was observed after the use of neutral red for distinguishing living, dead or damaged cells (Garrett et al, 2012, Gomaa & Elshoubaky, 2016, Vanderlei et al, 2016. Acyclovir did not exhibit cytotoxicity up to 200 μg mL -1 .…”

Perfil de flavonoides e avaliação do potencial antioxidante e citotóxico de Bauhinia purpurea (Fabaceae) da região amazônica

“…Os resultados mostraram um padrão de fragmentação característico para as duas substâncias, com perda das unidades de açúcar (m/z 609/301 e m/z 463/301) e a fragmentação das respectivas agliconas gerando o íon 1,2 A -(m/z 301/179), ambas em concordância com a literatura [37][38][39][40][41][42][43] (Material suplementar).…”

Phytochemical profile and in vitro evaluation of extracts from leaves of Drimys brasiliensis (Winteraceae) against bovine and equine herpesviruses

“…However, taxifolin showed an inhibitory effect on hepatitis A virus replication in vitro, while astilbin and isoastilbin do not have antiviral properties described yet (Biziagos et al, 1987). Quercetrin is also known as bioactive phytochemical for presenting some inhibitory effects (Almeida et al, 1998;Garrett et al, 2012;Chiow et al, 2016). Almeida, et al (1998) found varied degrees of this activity using Persea americana extracts and fractions against SuHV-1.…”