Haem compounds as bacterial growth promoters in whey: a possible application to bovine mastitis

The enhancing effect of haem compounds on the growth of Escherichia coli, Staphylococcus aureus and Streptococcus agalactiae in whey cultures was studied turbidometrically. Catalase, myoglobin and haemoglobin in concentrations 10(-5) to 10(-3) M enhanced bacterial growth. One explanation of this was the availability of iron by these haem compounds for the bacteria. However, evidence from experiments on free radical generating systems by t-BHP and hydrogen peroxide indicated that haem compounds scavenge activated oxygen products and so protect bacteria from oxygen toxicity.