Optimization of ultrasound-assisted extraction of phenolic compound from Pandan leaves (Pandanus Amaryllifolius)

Abstract

Pandan leaves or scientifically known as Pandanus amaryllifolius is used as a natural flavouring in South East Asian countries as it has a pleasant and sweet flavour. Due to its health benefits, it has been used as functional ingredients for wide range of applications such as pharmaceutical, cosmetic, food preservatives, flavour and fragrance industries. The study is to optimize the conditions for phenolic compounds extracted from Pandanus Amaryllifolius leaves using an ultrasound assisted extraction and to verify their antioxidant property. Three independent variables including extraction temperature, sonication time and solid-to–liquid ratio on the extraction yield of phenolic compounds were optimized using a central composite design-based response surface methodology. The plant extract obtained was assessed for its phenolic content and antioxidant activity by Folin-Ciocalteu method and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) method The optimal conditions to achieve maximum yields of phenolic compounds were extraction temperature 34 ̊C, sonication time 46 min and solid-to-liquid ratio 1:46 g/mL. The yield of phenolic compounds was 15.01 mg gallic acid equivalent/g pandan powder. The optimum yield of phenolic compound was corresponded to the value predicted from the CCD model with the desirability of 0.993. The plant extract also exhibits significant strong scavenging activity on DPPH with 68.60% and thus proven the antioxidant ability of pandan extract .These results indicate the suitability of ultrasound-assisted extraction for the extraction of phenolic compounds from Pandanus amaryllifolius leaves. This phenolic-enriched extract can be used as valuable antioxidant source for health benefits.