Optimization of the pH of mosquito repellent from citronella using response surface methodology

Abstract

Citronella is a source of essential oil obtained from steam distillation. The production of citronella oil is quite high; therefore, it can be applied in various fields. One of its applications is as an active substance in mosquito repellent creams. The citronella oil used in this study contained 11.59% citronellol content at a retention time of 16.544 minutes and citronellol content of 14.78% at a retention time of 27.165 minutes using the Gas Chromatography Mass Spectrometry method. In the manufacture of mosquito repellent creams, there are still mismatches in the composition between variables, so there is a need for optimization in this study. Optimization in this study using Response Surface Methodology model Central Composite Design on Statistica 10 software with 19 treatments. The method used was the addition of independent variables, citronella oil (2-4%), stearic acid (10-16%) and cetyl alcohol (4-6%) processed using the RSM-CCD method to determine the optimum pH. Optimization results with RSM at pH resulted in optimum conditions for citronella oil content of 2.1591%, stearic acid 18.045% and cetyl alcohol 6.6818% with a pH of 6.1.

Formulation and Evaluation of Citronella Oil (Cymbopogon nardus (L.) Rendle) Cream for Acne Treatment

“…This result agrees with Handayani et al, which found that the pH value will decrease along with the increase in cetyl alcohol content. 30 The five formulas proved stable because storage under ambient conditions and freeze-thaw cycles revealed no significant pH changes.…”