The effect of adding microalgae Spirulina platensis in making antibacterial soap

Abstract

The infection of methicillin-resistant Staphylococcus aureus (MRSA) has increased to 8% in 2017 in Indonesia. This infection commonly occurs in hospital thus, individuals must maintain personal hygiene such as using antibacterial soap. Several commercial antibacterial soap in Indonesia still use triclosan and triclocarban as antibacterial agent. This is a problem because they have been banned by Food and Drug Administration (FDA) in 2017. The use of them can disturb human reproduction system which lead to infertility and destroy algal growth. This study utilized Spirulina platensis and virgin coconut oil (VCO) as fatty acid source which reacted with sodium hydroxide to make soap. Furthermore, VCO also acted as antibacterial agent which can kill bacteria. Film-formed soap is expected to lessen soap and water waste. This soap was made by the hot process method at a temperature of 65°C. The examination done were free alkali, free fatty acid values, pH values, water content and antibacterial activity toward S. aureus. The result showed that all sample met the Indonesian National Standard (SNI) of hard soap. The use of VCO can substitute chemical-based antibacterial agent in soap because it has same ability in killing S. aureus in soap (at 25% dilution) which resulted in safer and environmentally friendly soap. The optimum composition in soap making were found in the use of 1 g S. platensis.