f225 Pumpkin

Pumpkin is a gourd-like squash of the genus Cucurbita and the family Cucurbitaceae (which also includes gourds). The Pumpkin is thought to have originated in Central America, possibly Mexico, but is now grown widely in temperate and tropical zones. It is an annual climber, typically with a large, round, ribbed, edible orange fruit. But Pumpkin comes in several other forms such as the finer-textured, straw-coloured Cheese Pumpkin.

The term “Pumpkin” is also sometimes applied to other squashes that have hard, smooth rinds (sometimes lightly ribbed) covering edible flesh and a central seed cavity; confusion is especially likely because some other squashes share the same botanical classifications as Pumpkins. Zucchini or courgette (also called “baby marrow”) is a small summer squash, but both Pumpkin and zucchini are known as Cucurbita pepo.

True Pumpkins can be differentiated from other squashes by their fruit stalk: it is hard and polygonal in Pumpkins, but soft and round in other squashes. But varieties within and between the species can cross-pollinate to produce hybrids: hence the great number of shapes and sizes, and the difficulty of strict botanical distinctions.

Pumpkin is unknown in the wild. Traditional Pumpkin pie usually a mixture of Pumpkin, eggs, sugar and spice, all baked in a pastry shell. On its own, Pumpkin can be boiled, baked, roasted, mashed or made into soup. It is a good source of beta carotene and vitamin E.

The seed can be eaten raw or cooked, and oil can be extracted from it (see Pumpkin seed f226). The leaves and young stems can be cooked as a potherb, and the flowers and buds can be cooked or dried. The vines, leaves, flowers and fruits have decorative functions.

The seeds and pulp are often used for medicinal purposes. The leaves are applied externally to burns. The sap of the plant and the pulp of the fruit can also be employed in this way.

IgE-mediated reactions

Pumpkin can induce symptoms of food allergy in sensitised individuals (1). Dermatitis, asthma, rhinoconjuctivitis, itching of the mouth, angioedema of the face and lips, generalised itching and mild dyspnoea after eating Pumpkin soup or thin vermicelli containing Pumpkin have been reported in a patient (1).

IgE antibodies to Pumpkin have been measured using the Pharmacia CAP System in children with food allergies (2), adults with atopic dermatitis (3), and children with atopic dermatitis and respiratory allergy (4).

An immediate-type reaction after contact with the pulp of butternut squash (Cucurbita moschata), resulting in dermatitis, has been reported (5).

Other reactions

Pumpkin seeds may be aspirated into the trachea in young children (6).

No allergens from this plant have yet been characterised. Whether the allergens in Pumpkin pulp is similar to those present in Pumpkin seed has not yet been determined. See Pumpkin seed f226.

A Bet v 6-related food allergen, isoflavone reductase, phenylcoumaran benzylic ether reductase, has been detected in the closely related zucchini (7). Zucchini may also contain a profilin (8).

Cross Reactivity

An extensive cross-reactivity among the different individual species of the genus could be expected, as well as to a certain degree among members of the family Cucurbitaceae (9). Clinical cross-reactivity has been demonstrated among Pumpkin, Pumpkin seed, muskmelon, Watermelon, Cucumber and zucchini (1).

A cDNA clone encoding a Soybean allergen, Gly m Bd 28K, has been isolated. The polypeptide for the cDNA clone exhibits high homology with the MP27/MP32 proteins in Pumpkin seeds, and with the Carrot globulin-like protein. The clinical significance of this has not yet been determined (10).

The closely related zucchini has been implicated in Latex-fruit syndrome. Cross-reactivity was demonstrated with Hev b6.01, the chitin-binding protein (11).

Last reviewed : June 2022