I don't know if it's available in USA, but if you want to try, you can buy it here:
www.frusano.com/Dietary-supplement/Fruct...sin-10-pcs::128.html
My doubt is that I don't know if it is really efective. I was looking for xylose isomerase enzyme, also called glucose isomerase, and it is the same that is used to make high fructose corn syrup. I look at the reaction and is an equillibrium Frutcose=Glucose. I suppose that the idea is that this equillibrium is desplaced because glucose is absorved, and if there is more fructose than glucose, this enzyme will transform fructose to glucose. But if you have eaten more glucose than fructose, will be usefull this enzyme? will it really transform fructose to glucose in this case? or will it transform glucose to fructose as it does in HFCS?