What percentage of human saliva is salivary amylase?
I don’t find any literature where actual amylase content is measured. Mostly they measure an index of amyolytic activity, which is an indirect indication of the amount present. Many papers report having to dilute saliva 1:100 or 1:200 with water in order to get a properly graphable result; this tells me that the concentration is fairly high. One must remember that amylase is an enzyme catalyst and is not used up in the process of breaking down carbohydrate, so fairly high in the case of a catalyst as not all that high relevant to non-catalytic components. I would guesstimate something on the order of 1%, probably less. Also, amylase content has been shown to vary depending on the individual, the state of the individual regarding stress, hunger level, etc., so no number would be spot on. Here are some representative articles on the subject:
