In vitro Protective Effect of Chemically-Characterized Flower Extracts of Clitorea ternatea L. Against Hydrogen Peroxide Induced Cytotoxicity in Human Keratinocytes (HaCaT)

A Zakaria Nik Nur; E Okello; M Howes

doi:10.1055/s-0037-1608462

Planta Medica International Open, Table of Contents

Planta Medica International Open 2017; 4(S 01): S1-S202
DOI: 10.1055/s-0037-1608462

Poster Session

Georg Thieme Verlag KG Stuttgart · New York

In vitro Protective Effect of Chemically-Characterized Flower Extracts of Clitorea ternatea L. Against Hydrogen Peroxide Induced Cytotoxicity in Human Keratinocytes (HaCaT)

Authors

A Zakaria Nik Nur

¹School of Agriculture, Food and Rural Development (AFRD), NE1 7RU Newcastle Upon Tyne, UK, Newcastle Upon Tyne, United Kingdom

²Faculty of Agro-based Industry (FIAT), Universiti Malaysia Kelantan (UMK), 17600 Jeli, Kelantan, Malaysia, Kelantan, Malaysia
E Okello

¹School of Agriculture, Food and Rural Development (AFRD), NE1 7RU Newcastle Upon Tyne, UK, Newcastle Upon Tyne, United Kingdom
M Howes

³Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond TW9 3AB, UK, Richmond, United Kingdom

Abstract

Full Text

Clitoria ternatea (Leguminosae), commonly known as the butterfly pea, is easily recognizable by its deep blue flowers. The leaves and roots of the plants are well research. However, very little is known about the flower parts of the plant. In Malaysia and Thailand, the flower part was used as a food colorant in the traditional dish, drink as herbal tea and consumed as vegetable salad for health benefits, particularly as defence against skin aging. This study was conducted to investigate the protective effect of C. ternatea extracts against hydrogen-peroxide induced cytotoxicity in HaCaT cells (human keratinocytes) as skin cells model. Two extracts (aqueous and 70% ethanol) were prepared to mimic the traditional methods of preparation. The antioxidant potential of the extracts was determined using diphenyl-picryl hydrazine (DPPH) and 2, 2'-azino-bis (3- ethylbenzothiazoline-6-sulphonic acid (ABTS) assays, expressed as Trolox equivalent (TE)/mg extract. The protective effect against hydrogen-peroxide induced cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium (MTS) assay. The antioxidant assays showed the TE/mg extract for C. ternatea ethanol extract (CTE) were significantly higher than C. ternatea water extract (CTW) (p < 0.05). HaCaT treated with CTW extract showed to have higher percentage viability compared to untreated HaCaT after exposure to 200µM hydrogen peroxide (p < 0.05). No protective effect was observed from CTE extract. High resolution liquid chromatography-mass spectrometry (LC-MS) revealed the detection of compounds assigned as flavonol glycosides (derived from quercetin and myricetin), anthocyanins (derived from delphinidin) and coumaric acid derivatives (coumaroylsucrose and coumaroylglucose) in CTE and CTW. The higher antioxidant potential in CTE, observed by higher antioxidant potential to inhibit free radicals but antagonistically prevented the protective effect against hydrogen peroxide-induced cytotoxicity as opposed to HaCaT treated with CTW may be due to variation in the relative levels of phytochemicals in the CTE and CTW extracts.