Myrtaceæ.
Myrtle Family.
Psidium pomiferum, L. (P. aromaticum and P. pyriferum, Blanco.)
Nom. Vulg.—Guayabas, Sp.; Bayabas, Guayabas, Tayabas, Tag., and other dialects; Guava, Eng.
Uses.—The green fruit is acid and very astringent. The stage of development when it is best eaten raw, is just before it ripens, for then its acidity has lessened, it is not astringent and does not emit the strong odor, so disagreeable to many, that characterizes the ripe fruit. When fully ripe it is sweet, non-astringent and very bland, and this is the stage when it is best for making the jellies and preserves so popular in the Philippines.
The bark, especially that of the root, is highly astringent and a decoction of it is used for diarrhœa and as a wash for ulcers. Dr. Waitz has successfully used the following formula in treating the chronic diarrhœa of children:
| Root bark of guava | 15 grams. |
| Water | 180 grams. |
Boil till reduced one half. Dose, a tablespoonful every 2 or 3 hours according to age.
A decoction of the shoots is very useful in stomatitis, cutaneous eruptions and ulcers. Dr. Waitz advises his formula in prolapsus recti of children. It is also of value as an injection in diarrhœa and dysentery.
Botanical Description.—A tree, about 10° high, branches square and somewhat winged towards the ends. Leaves opposite, oblong, obtuse, downy, aromatic in odor. Petiole very short. Flowers axillary, solitary, white and fragrant. Calyx adherent, the border breaking in 3, 4 or more unequal parts when the flower expands. Corolla, 5–6 petals, inserted on the calyx, curved downward. Stamens numerous, inserted in the calyx, as long as the corolla. Style same length as stamens, awl-shaped. Fruit somewhat pear-shaped, with 4 or 5 ribs that disappear at maturity, 4 or more cells each with many small, hard, irregular seeds. In the Philippines the fruit grows to the size of a small pear.
Eugenia Jambolana, Lam. (Calyptranthes Jambolana, Willd. and Blanco; Syzygium Jambolanum, DC. and Blanco.)
Nom. Vulg.—Lomboy, Duhat, Duat, Tag., Pam., Vis.; Jambul or Black Plum, Indo-Eng.
Uses.—The ripe fruit, so dark a purple in color that it seems black, is edible and very popular in the Philippines, though not considered choice. Some suppose it to be harmful, but it is in reality very easy of digestion.
The syrup of the fruit juice, and the decoction of the trunk bark are both very efficacious in the treatment of diarrhœa and dysentery.
Syrup of Jambul.—
| Juice of ripe fruit | 500 grams. |
| White sugar | 950 grams. |
Dissolve in a covered water-bath, strain through woolen cloth and put aside.
Dose.—60–200 grams a day.
The juice of the leaves is also used to treat diarrhœa. A Hindoo physician, Bhavaprakasa, advises the following receipt:
| Juice of leaves of lomboy } | |
| Juice of leaves of manga } | āā 4 grams. |
| Pulp of Terminalia chebula } |
Give in one dose in a little goat’s milk and honey.
A sort of wine of very agreeable taste is made from the fruit juice. Lately the powdered seed has been recommended in the treatment of glycosuria or at least it has been stated that its internal use lessens and finally abolishes the glucose from the urine of the patient. It has even been affirmed that while under this treatment the patient may eat glucose-forming foods without fear of glycosuria supervening.
The chemical composition of the seeds are as follows:
| Essential oil | Traces. |
| Chlorophyl and fatty matters | 0.37 |
| Resin soluble in alcohol and ether | 0.30 |
| Gallic acid | 1.65 |
| Albumin | 1.25 |
| Pigment soluble in water | 2.70 |
| Water | 10.00 |
| Insoluble residuum | 83.73 |
| 100.00 |
Dujardin-Beaumetz has tested the therapeutic value of these seeds in diabetes but with negative results. Scott has maintained that by adding the powdered seed to a mixture of malt and starch, fermentation is impeded; but Dr. Villy in the laboratory of Dujardin-Beaumetz has demonstrated that such is not the case. Contrary to the opinions of those physicians who stated that “jambul” was capable of causing the glucose to disappear from the urine of diabetic patients without concurrent diabetic regimen, Dujardin-Beaumetz observed in his trials of the drug that the slightest relaxation of the regimen was followed by an increase of glucose. Under the influence of the medicine in doses of 2–10 grams daily, at the same time maintaining a strict diabetic diet, the Parisian therapeutist noted that the glucose disappears from the third to the fifth day; but this occurred only in cases of medium intensity, whereas in severe cases the medication produced no effect. Upon stopping the treatment the sugar reappeared.
Botanical Description.—A tree, 15–20° high, with leaves opposite, acute, entire, ovate, lustrous, very smooth. Flowers in racemose panicles with peduncles opposite. Calyx superior, with 5 small teeth and a deciduous cover composed of many orbicular pieces joined below. Corolla none. Stamens numerous, inserted on the edge of the calyx. Stigma pointed. Fruit black, oval, crowned with the calyx; one long cylindrical seed with membranaceous epidermis.
Habitat.—Common all over the Archipelago. Blooms in February.