Reduction of Microbial Contamination in Kaolin from Belitung Island, Indonesia

Abstract

Kaolin is often used as an excipient in pharmaceutical and cosmetic industries as well as an anticaking, bulking, absorbent, and opacifying agent. It is also required in some cosmetic industries with a limited number of microbial contaminations, but no study has explored the reduction of these contaminant microbes based on the requirements. Therefore, this study aims to produce kaolin that complies with the microbial contamination specifications. Several methods were used in this study to reduce the microbial content, including heating, sterilization using anautoclave, as well as soaking with ethanol, methanol, and chloroform. The number of microbial contaminations was then measured using the Petri dish method. The result showed that the 2 h heating treatment was not sufficient to eliminate microbial contamination even at a temperature of 250°C, hence, it was combined with the addition of sodium hypochlorite to obtain a better outcome. Furthermore, autoclave treatment at 121°C for 20 min with or without pre-treatment successfully reduced the population of microbes to <102 per gram and this met the standardrequirement for cosmetic industries.