Evaluation of anti-ageing properties of Moringa oliefera Lam., Centella asiatica (L.) Urban, Clitoria ternatea L. and Cosmos caudatus Kunth. for potential application as cosmeceuticals

Ph.D Thesis ; Background. In 2010, the launch of the Malaysian Economic Transformation Programme (ETP) changed the agriculture sector in Malaysia from “traditional” agriculture into an agribusiness sector. The National Key Research Area (NKRA) in the agriculture sector focuses on raising the status of local herbs for potential commercialisation. Application of local herbs in the cosmetics industry seems to be a promising investment with the current high demand for natural and organic cosmetics worldwide. Given this scenario, this study focused on investigating the anti-ageing properties of selected medicinal plants which are considered as underutilised in Malaysia, as scientific evidence to support their traditional and cosmetic usages is lacking. Aim. This project aims to add agricultural and commercial value to the selected medicinal plants; Moringa oliefera Lam., Centella asiatica (L.) Urban, Clitoria ternatea L. and Cosmos caudatus Kunth. which were investigated for their anti-ageing properties (antioxidant, anti-collagenase, anti-elastase and anti-tyrosinase activities) and their protective effects against oxidative-stress induced by hydrogen-peroxide and UV radiation in vitro. Methods: Two extracts per plant species were prepared using water and 70% ethanol to mimic either the traditional methods or industrial extract preparations. The total phenolic content (TPC) was determined by the Folic Ciacalteau method. High-performance liquid chromatography-mass spectrophotometry was performed to characterise the individual components of the extracts and to chemically authenticate the plant samples. Antioxidant activities were determined using diphenyl-picryl hydrazine (DPPH), 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS). The results are expressed as Trolox equivalent (mg/g dried extract) and IC50 (μg/mL). The anti-collagenase and anti-elastase activities were measured by fluorescence assays and anti-tyrosinase activity using a colourimetric assay. The iv results are expressed as percentage ...