How to color axis tick labels with f(z)?

Hi everyone,

Is there a way to color the tick labels of my category plot with f(z)?

I have subcategories, and to make the figure easier to understand I would like to color each subcategory label by its overall family (ie, all carbohydrates blue, all N compounds red, etc). Is this possible? Or is there another way to clearly show the families that my x-axis subcategories belong to, on a category plot?

Thank you for any advice you can give~