Effect of titanium on the activity of lipoxygenase

Lipoxygenase was extracted from untreated tomato fruits and those treated with titanium ascorbate (TITAVIT) at the last stage of ripening. It was found that titanium (Ti) had a activating effect on lipoxygenase so that the development of red pigments was inhibited to some extent. The addition of Titavit to the reaction mixture resulted in a lag period of about 1 minute to lipoxygenase‐catalyzed linoleic acid oxidation, whereas, incubation of this complex with enzyme extract for 10 minutes significantly increased enzyme activity. Activation of lipoxygenase by Ti was confirmed when addition of titanium chloride also increased the enzyme activity. Titanium also increased the stability of lipoxygenase preparations when kept under refrigeration.