Formulation of disinfectant liquid cleaning detergent using violacein as antibacterial agent for household applications

Abstract

Synthetic antibacterial agents and surfactants have been used widely in detergent formulation. These synthetic antibacterial agents and surfactants have major drawbacks in both environment and health. Synthetic surfactants and antibacterial agents are non-biodegradable, toxic to aquatic life and can cause skin irritation to human. Thus, violacein pigment, a natural antibacterial agent obtained from Chromobacterium violaceum UTM5 and a plant-based surfactants such as sodium laureth sulphate (SLES), coconut fatty acid diethanolamide (CDE) and cocomidopropyl betaine (betaine) were used in this study. Two types of builder which are plant-based, (sorbitol) and synthetic-based, (ethylenediaminetetraacetic acid) were added. The builder act as anti-redeposition agent and help to soften the hard water, thus improving the washing performance of the surfacants. The physical properties of the detergent formulation were tested based on the following properties: pH, foaming ability, viscosity and washing performance. Six formulations of the same ratio of surfactants (SLES:CDE:betaine;8.31:1:2) but different ratio of sorbitol and EDTA were prepared. Five different concentrations of violacein pigment was added in the formulation which contained 5% sorbitol as it give the best physical performance with 12.36 cm³ volume of foam, with the viscosity 3.02 mm²s^-1, washing performance of 97.94% and pH of 8.80. Then antibacterial test was performed using disc method. The antibacterial test performed showed the detergent formulation with different concentrations of violacein pigment have different antibacterial properties which were determined by the inhibition zone. The formulation with high concentration of violacein pigment have high antibacterial properties than others. Comparison study with commercial detergent products in the market show a comparable physical performance and antibacterial properties although it only use three surfactant, one builder and an antibacterial agent in the formulation.