THE EFFECT OF CLOVE AND CINNAMON ON REDUCTION OF STAPH AUREUS BIOFILM FORMATION

The term ‘biofilm’ refers to micro-organisms attached to and growing, or capable of growing, on a surface. This includes cells or spores that are attached to a surface but have yet to produce a biofilm matrix. Biofilms have become a major issue within the dairy industry and are well recognised as sources, or potential sources, of contamination by spoilage or pathogenic microorganisms, which can decrease product safety, stability, quality and value.

 In dairy manufacturing plants, biofilms can be divided into two categories: process biofilms, which are unique to processing plants and form on surfaces in direct contact with a flowing product; and environmental biofilms, which form in the processing environment, such as in areas where cleaning and sanitation are poor and around drains. Typically, efforts are made to remove biofilms with several sanitizers on the market and for those particularly persistent steam sterilisation, UV and peroxide treatment are recommended. Increasingly though, alternative methods are also considered, some of which are ‘natural enemies’. Such a study was done by Dr P.E. Budri and colleagues, which they published in the Journal of Dairy Science, Volume 98 (Issue 9) of 2015, pages 5899 to 5904, with the title: Effect of essential oils of Syzygium aromaticum and Cinnamomum zeylanicum and their major components on biofilm production in Staphylococcus aureus strains isolated from milk of cows with mastitis.

 In mastitis cases, Staphylococcus aureus is one of the microorganisms most commonly isolated. Staph. aureus also forms biofilms which facilitate the adhesion of bacteria to solid surfaces and contributes to the transmission and maintenance of these bacteria. It has been suggested that the essential oils of Syzygium aromaticum (clove; EOSA) and Cinnamomum zeylanicum (cinnamon; EOCZ) may be effective to combat biofilms. Therefore the influence of these compounds, as well as their major components, eugenol and cinnamaldehyde, on Staph. aureus biofilm formation on different surfaces was investigated.

The results showed a significant inhibition of biofilm production by EOSA on polystyrene and stainless steel surfaces (69.4 and 63.6%, respectively). However, its major component, eugenol, was less effective on polystyrene and stainless steel (52.8 and 19.6%, respectively). Both EOCZ and its major component, cinnamaldehyde, significantly reduced biofilm formation on polystyrene (74.7 and 69.6%, respectively) and on stainless steel surfaces (45.3 and 44.9%, respectively). These findings suggest that EOSA, EOCZ, and cinnamaldehyde may be considered for applications such as sanitization in the dairy industry.