Planta Med 2014; 80 - P2B42
DOI: 10.1055/s-0034-1394919

Phenol content, antioxidant and α- and β-glucosidase inhibitory activities of an Anacardium occidentale stem bark Traditional Herbal Preparation

S Encarnação 1, M Malmir 1, D Sousa 2, IM da Silva 1, C Mello-Sampayo 1, R Serrano 1, B Lima 1, O Silva 1
  • 1Research Institute for Medicines and Pharmaceutical Sciences (iMed.ULisboa), Pharmacological and Regulatory Sciences, Faculty of Pharmacy, University of Lisbon, Av. Prof. Gama Pinto, 1649 – 003 Lisbon, Portugal
  • 2Department of Animal Sciences, Federal Rural University of the Semi-arid (UFERSA), BR 110 – Km 47, 59625 – 900, Mossoró, Brazil

Introduction: Anacardium occidentale L., commonly known as cashew tree, has been traditionally used in several countries of Asia, Africa and America, due to its antihyperglycemic properties.

Aim of work: To perform comparative studies between Traditional Herbal Preparation (THP) of A. occidentale stem bark red (AOR) and white (AOW) in order to assess their free radical scavenging, α- and β-glucosidase inhibition activities and total phenolic content.

Methods: THP total phenol content was determined by the Folin-Ciocalteu method [1], using gallic acid as standard. Simultaneously, the free radical scavenging activity of the THPs was assessed with a 1,1-diphenyl-2-picrylhydrazine (DPPH) assay, using ascorbic acid as reference standard [2]. Moreover bioautographic assays with thin layer chromatography were performed for the detection of α- and β-glucosidase inhibitors [3].

Results: Total phenolic content was found to be 51.3 ± 1.6 and 58.0 ± 0.4 mg of gallic acid equivalent per gram of dried cashew stem bark in AOR and AOW THP, respectively. Concerning the free radical scavenging activity, IC50 value was 180.7 ± 6.7 µg/mL for the AOR THP and 143.8 ± 2.8 µg/mL for the AOW THP. Bioautography showed two chromatogram zones that were identified as α-glucosidase (Rf between 0.55 and 0.68) and β-glucosidase (Rf between 0.63 and 0.87) inhibitors in both THP.

Conclusion: Assessed THP proved to be a source of natural antioxidants that may scavenge free radicals. According to data obtained from all experimental assays, AOW THP has higher antioxidant activity and total phenolic content than AOR THP. Moreover, extracts from both types of A. occidentale promoted inhibition of α- and β-glucosidase.

Acknowledgements: This work was supported by grant Pest-OE/SAU/UI4013/2011 from Fundação para a Ciência e Tecnologia, Lisbon, Portugal.

Keywords: Cashew stem bark, Traditional Herbal Preparation

References:

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[3] Simões-Pires C, Hmicha B, Marston A, Hostettmann K. A TLC bioautographic method for the detection of α- and β-glucosidase inhibitors in plant extracts. Phytochem Anal 2009; 20: 511 – 515.