A comparative study of regenerated bamboo, cotton and viscose rayon fabrics. Part 2: antimicrobial properties

Since regenerated bamboo fibres (also referred to as bamboo viscose) became commercially available in 2006, consumers have been bombarded with contradictory information regarding products made of these fibres, their potential end-uses and their properties. On the one hand, manufacturers and marketers make broad claims about the antimicrobial and environmentally friendly characteristics of products made of regenerated bamboo, while, on the other hand, there is an outcry from consumer watchdogs that many of these claims are false and have not been properly proven. Very little information is available about the validation of these properties through scientific research studies. It is also evident that information about natural bamboo and regenerated bamboo fibre products is often confusing. Regenerated bamboo (also referred to as bamboo viscose or bamboo rayon) is manufactured from natural bamboo fibres in a regeneration process by which bamboo pulp is refined from the stems of the bamboo plant in a process similar to that used to manufacture viscose rayon fibres. The severity of this process has led to scepticism as to whether the antimicrobial properties of the bamboo kun remain unchanged in regenerated bamboo fibres. The question has been raised as to whether residual chemicals on the spun fibres could be the cause of antimicrobial properties.   The main objective of this study was to investigate the claim that regenerated bamboo fibres have inherent antimicrobial properties as a result of the bamboo kun present in the raw material from which the fibres are regenerated. For this purpose, the antimicrobial properties of regenerated bamboo fabric were compared to those of viscose rayon and cotton fabrics. The results confirmed that cotton fabric (used as a control) exhibited no antimicrobial activity. However, the antimicrobial effect of the regenerated bamboo and viscose rayon samples was significantly higher than that of the cotton sample, for both Gram-positive bacteria and Gram-negative bacteria. The claims made concerning the bacteriostatic or antimicrobial properties of regenerated bamboo could thus not be proven as false. Statistically, the regenerated bamboo fabrics did not perform better than the viscose rayon fabrics in our tests and did not kill all the bacteria in the solution. No evidence was found that regenerated bamboo fibre fabrics are superior to other regenerated cellulose fibres such as viscose rayon, nor that the antimicrobial properties of natural bamboo remain unchanged in regenerated bamboo fibres.