Optimization of hydrodistillation extraction conditions of zerumbone from Zingiber zerumbet rhizome

Abstract

The optimization of zerumbone extraction from Zingiber zerumbet was investigated using a hydrodistillation extraction method. In the present work, the response surface methodology (RSM) based on a central composite design (CCD) was used to determine the optimum condition for the extraction of essential oil and zerumbone content from Z. zerumbet rhizome. Three evaluated process variables were the extraction time (60-120 min), raw material to solvent ratio (1:15-1:25) and particle size (250-2000 μm). The CCD consisted of 21 experimental points and three replications at the centre point. Data were analysed using Design Expert software 6.0.6. The optimal conditions suggested by the software for maximum yield of Z. zerumbet essential oil and zerumbone content were at 74.29 min, ratio of material to solvent of 1:18.76 and particle size of raw material of 2000 μm. From the experiment, the yield of Z. zerumbet essential oil was 4.10% slightly higher than the predicted value of the software (3.73%). Whereas for zerumbone content, it was observed that the amount obtained from the experiment analysis was 1.20% which was slightly lower compared with the predicted value of the Design Expert software (1.58%). The experimental values fell in a range between lower limit and upper limit of the predicted table indicating suitability of the model employed and the success of RSM in optimizing the extraction conditions. Hence, the CCD model can be used to predict the zerumbone content in essential oil extraction from Z. zerumbet in a hydrodistillation extraction system.