Bacillus cereus

What is Bacillus cereus?

Bacillus cereus (B. cereus) is a class of bacteria which under adverse conditions can form spores.¹ A spore is a “dormant, nonreproductive body formed by certain bacteria, often in response to a lack of nutrients, and characteristically being highly resistant to heat, desiccation, and destruction by chemicals or enzymes.”² Characteristic of a spore is its ability to remain dormant for long periods in extreme environmental conditions and then reawaken when conditions turn favorable.³ 

B. cereus is part of a class of spores known as “endospores”. Endospores can withstand extremes in temperature from nearly absolute zero up to 150°C.  They can also withstand various chemicals, ultraviolet radiation, drought, sterilization, pasteurization, antimicrobial treatments, and lack of nutrients.^4,5 These endospores come back to life once the surrounding conditions favor bacterial growth.⁶ 

Favorable growing conditions for B. cereus endospores include any temperature between 8° and 55°C.⁷ This bacteria can be found in soil, on vegetables, and in many raw and processed foods.⁹ Particularly troubling for the food processing and agricultural sectors, B. cereus endospores are resistant to cleaning procedures, as they are quite good at sticking to processing equipment.⁸ Notwithstanding its prevalence in the food sector, this bacterium also impacts other sectors such as healthcare.¹⁰ 

The Problem

When B. cereus endospores are exposed to favorable growing conditions, they can contaminate raw or processed food or damaged human skin.¹¹ This contamination can become toxic. If humans somehow engage this toxin, it can lead to mild food poisoning or potentially very dangerous non-intestinal infections.¹²

Effectiveness of HOCl

Research on HOCl has been ongoing for several decades. In 1973, a research team tested the efficacy of “electrolyzed oxidizing” (EO) water in killing the B. cereus bacterium under a variety of conditions. What they found was EO water killed 99.9% of the bacteria in all situations within 5 minutes.¹³ Furthermore, they determined HOCL was the agent within the EO which was responsible for the killing of the B. cereus.¹⁴ In 2000, a research team confirmed HOCL was the primary agent within “electrolyzed oxidizing” water which was responsible for killing B. cereus endospores.¹⁵ As B. cereus endospores are very difficult to kill, it is indeed encouraging HOCl has been shown to be effective at killing these hard-to-kill bacterium.