Pius Font i Quer (Lérida, April 9, 1888–Barcelona, January 2, 1964) was a Spanish botanist (taxonomist and phytogeographer), pharmacist, and chemist who stood out as one of the most important figures in Spanish botanical science in the mid-20th century. He was also a professor and disseminator.
The blueberry is a low shrub that only exceptionally reaches a height of 3 feet; it drags its woody branches, which are dark in color, along the ground, beneath the leaf litter or mossy lawns, where they root at intervals and send up erect, angular, and leafless twigs at the top. The leaves, hairless like the entire plant, are elliptical or between ovoid and elliptical in shape, supported by very short petioles and have finely serrated edges, with a hair at the apex of each tooth.
The flowers are solitary or paired, with a pinkish-purple corolla in the shape of a wide, flat base and very constricted at the top, where five small rounded lobes are formed and spread outward. The fruit is a rounded berry, 7 to 9 mm in diameter, dark bluish-black in color, covered with a blue bloom and with a crown-like rim at the top; its flesh, with a pleasant sweet-sour taste, is wine-colored and contains several seeds in the central part. The leaves taste slightly tart.
It blooms from April to June and ripens its fruit from July onwards.
It grows profusely and often forms extensive blueberry patches in the forests and moors of non-calcareous lands, mainly in the mountains of the northern half of the Iberian Peninsula, up to Montseny, the mountains of Teruel (in significant decline in Orihuela de Tremedal, where it barely flowers), Sierra de Guadarrama, Sierra de Gredos, Serra da Estrela, etc.
The leaves should be collected when the plant reaches its full development, generally in the month of June. The berries, in the months of August or September, and even in July in the early ones; in any case, only when they have taken on a bluish, almost black color, a sign of full maturity.
The leaves should be dried as quickly as possible and stored in a cool, dry place. The fruits can be eaten when freshly harvested; they are sweet and rich in vitamin C. Adding sugar, they can be prepared as very pleasant-tasting preserves. When only a small amount of sugar is added, at most as a third of the extracted juice, fermentation occurs, slowly turning into blueberry wine, prepared in Central Europe.
Like bearberry leaves, blueberry leaves contain significant amounts of tannin, quercetin, arbutin, and quinic acid; and a bitter substance, ericoline, to which glycosidic properties are attributed, but which, according to others, is nothing but arbutin itself. In their fresh state, the leaves contain 64 mg of vitamin C, and about three times more when dried.
The fruits, containing 1 to 5% tannic substances, anthocyanins, sugars, and organic acids. According to H. Kaiser, the centesimal proportion of the acids found in the juice of these freshly harvested berries is as follows:
The coloring matter of the fruit, called myrtillin, according to Willstätter and Zollinger, is a monogalactoside of myrtilidine, easily soluble in water and alcohol. It also contains, in a fully ripe state, from 4.78 to 2.28% of inverted sugar. In dried fruits, it increases from 21.29 to 30.67%. Sucrose is only found in immature berries.
It is an astringent and antiseptic plant, with anti-diabetic properties attributed to it.
In folk medicine, it has been used for countless ailments, often without a basis. Due to its content of arbutin, it can produce effects similar to those of bearberry, not only regarding the bladder and urinary tract but also in certain intestinal diseases. In this case, infusions prepared with the leaves regularize bowel movements, eliminate their fetid odor, and prevent the production of intestinal gases. They also facilitate the expulsion of small intestinal pinworms.
The popular use of blueberries for diabetes was considered by scientific medicine a few decades ago. Some American doctors (specifically Allèn) have used a plant-derived myrtillin. This product would have many of the virtues of insulin without some of its disadvantages.
Other authors, experimenting on animals, have confirmed these opinions. In the case of mild to moderately severe diabetes, H. Seel believes that prolonged medication with blueberry leaves not only reduces the sugar excreted in the urine but also the blood content. Other doctors, on the other hand, deny this hypoglycemic action or attach little importance to it. Oettel believes that the increase in blood glucose, which has been observed repeatedly when large amounts of blueberry fruits are administered to the patient, is produced by the free hydroquinone, which in the leaves can reach approximately 1%.
Finally, the astringent virtues of this plant are used to treat bleeding hemorrhoids, with washes and irrigations of leaf decoction.
Use. An infusion is prepared with 1 ounce of crushed or shredded blueberry leaves and 1 liter of boiling water. Strain when it has cooled, without removing the leaves from the water. Three or four cups of this infusion are taken daily in cases of chronic dysentery or diabetes. It should not be sweetened.
A decoction is prepared with 2 ounces of the fruits and 1 liter of water; it is boiled for a quarter of an hour and strained when cold.
For blueberry cure, as for grape cure, fresh fruit is taken, in quantities of 0.5 to 1 kg per day. It is especially useful for regulating intestinal functions and preventing putrid fermentations.
The pharmacologists of antiquity do not tell us about blueberries; this plant does not grow in Greece, and in Italy, it is only found in the high mountains, from the Alps to the Abruzzos.
However, authors wonder which plants were Pliny’s vaccinios. Mattiolli, like the majority who dealt with this problem, believed that they were hyacinths.
Ignacio de Asso, relying on information published by Francheville in 1767, has no doubt that the vaccinium of the ancients is the blueberry. He provides quotations from Virgil, Pliny, and Vitruvius, and the latter author precisely alludes to the same mixture as Francheville: “Eadem purpuram faciunt elegantem” (“They make the same elegant purple”).
BILBIOGRAPHY: “MEDICINAL PLANTS, THE RENEWED DIOSCÓRIDES” BY PIO FONT QUER