Quantification of bufadienolides in the poisons of Rhinella marina and Rhaebo guttatus by HPLC-UV

Abstract

Bufadienolides are the main active compounds in the Bufonidae family of frogs. Recent studies have demonstrated cytotoxic and/or antitumor activity in these molecules. A HPLC-DAD method was developed and validated to quantify three bufadienolides (telocinobufagin, marinobufagin and bufalin) in ethyl acetate extracts of the cane toad poison frogs and smooth-sided toad. The chromatographic analysis was performed on Phenomenex Luna C18 (250.0 × 4.6 mm, 5 μm), using gradient elution with acetonitrile and water, at a flow rate of 1.0 mL min(-1) and detection at 296 nm. The method showed linearity (r > 0.999) and adequate recovery values (86%-111%). The limits of quantification of bufadienolides were 7.4 μg mL(-1) for telocinobufagin, 4.2 μg mL(-1) for marinobufagin and 4.0 μg mL(-1) for bufalin. Intraday and interday values of the method were evaluated and presented standard deviation values lower than 5%. The method was successfully applied to quantify the bufadienolides in the venom extract of the cane toad, which showed a content of 60% of marinobufagin. The same method was not selective for the venom extract of the Rhaebo guttatus, despite being linear, accurate and precise, requiring the development of a technique that presents a greater selectivity.

Chemical and Pharmacological Screening of Rhinella icterica (Spix 1824) Toad Parotoid Secretion in Avian Preparations

“…Cell viability can be altered by toxic conditions that include the production of reactive oxygen species, excitotoxicity, necrosis and apoptosis [73][74][75][76]. In addition, anti-AChE compounds can protect cells from neuronal death and cognitive impairment in neurodegenerative diseases [31,33,[76][77][78][79][80]. The inhibition of Na + /K + -ATPase is one of the mechanisms implicated in the cytotoxicity of cardiac glycosides [81].…”

Biodiversity studies through public-private partnership (PPP): The case of Fazenda São Nicolau in the northwest of Mato Grosso

“…Biodiversity components with medical applications are also under investigation, including frogs that produce toxins that can provide treatments for malaria and cancer (Ferreira et al 2013, Banfi et al 2016, Kerkhoff et al 2016, Ferreira et al 2017. Other studies targeted the value of reforestation comparing undisturbed native forest sites with pasture and abandoned pasture sites.…”

Marinobufagenin extraction from Rhinella marina toad glands: Alternative approaches for a systematized strategy

“…MBG as well as other bufadienolides in biological fluids is becoming a real concern. Several methods, mostly designed for therapeutic drug monitoring of Traditional Chinese Medicine in plasma and/or serum, have already been published but are all facing the same issue: the tricky access to pure standard material for the setup and validation of the analytical methods for MBG measurement . MBG is also found in the skin and parotoid gland secretions of Bufonidae toad species and especially in the secretions of the Rhinella marina (L.) toad.…”