Fruits of plum tree ( Prunus ) Rosacea family , plums are round or oval , pulp and peel yellow or red - purple , covered with a waxy substance - prunina . Inside contains a grain elongated and pointed. Originating in Syria , plum fruits are found in many varieties and colors, " Prunus domestica " being the most prevalent species .

Plums helps digestion and have a laxative effect . They contain water ; sugars , distributed between glucose, fructose and sucrose ; dietary fiber ( cellulose and pectin ) ; organic acids , which favors the elimination of uric acid ; minerals , especially potassium; vitamins ( B1 , B2 , B3 , B6 , C , E and D ) ; anthocyanins ( in the shell ) , which gives the fruit antioxidants specific color ; tannins and bitter substances in the leaves and bark of the tree . Prunes have a higher caloric content than fresh and a higher concentration of vitamins and minerals .