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Name: Linda Martin
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

What exactly is the astringent that is found in persimmons that makes your mouth pucker?

The astringents in persimmons are tannins (tannic acid) and other polyphonously compounds. There are many forms of tannins, but generally there are two groups: 1) flavonol derivatives and 2) esters of sugar, usually glucose, with one or more trihydroxybenzenecarboxylic acids. Tannins can be found in many plants and trees, including oak, sumac, myrobalan, and the Chinese nutgall. How do astringents work? Basically, they reduce the permeability of cell membranes and hardens the cement substance of the capillary endothelium (the inner cell layer of capillaries). In effect, this inhibits movement of plasma protein through capillaries, which thus reduces local edema (swelling) and inflammation. Muscle contraction and tissue wrinkling accompanies the effect. Since astringents do not penetrate very deeply into cells, the action is limited to the cell surface and interstitial (in-between cells) spaces. The American Indians had many uses for persimmons (scientific name: Diospyros virginiana L.). The infusion of the fruit was used to treat diarrhea, dysentery, uterine hemorrhages, and sore throats. The powdered seeds were mixed with water to make a drink for kidney stones. The boiled bark was used for sores of the mouth, lips and throat. A lot of good from a simple tree and its fruit!


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