First of all...according to basic food combining laws, fruit and vegetables should never be mixed. Leave out all the fruits...or do fruit juices separately (morning is good for fruits). Then even when combining fruits you should not mix some fruit juices with each other. Same with vegetables (carrot and tomato do not mix for example) (do a Google search for food combining and the proper combining lists would apply to the juices of the foods as well.)
When you juice make sure you don't eat solid food for 2 hours before or after. The juices can make your foods ferment and improperly digest which is causing the acne. Broccoli & cabbage have a lot of sulphur and could contribute to excessive gas.I've found after dealing with customers for years in natural food stores that Acne is originating in the bowels, from putriification. Toxins are not being eliminated enough in the bowel or urine and come out the skin (which is our largest elimination organ!) Barley green/wheat grass/chlorella/spirulina can really help the acne. Plus probiotics of course.