Passionfruits Passiflora edulis native to an area going from Southern Brazil to Northern Argentina. There are no Passiflora species indigenous to Africa. There are, however, in Asia. I have no information on the edibility or otherwise of the Asian species, but  many of the 120 or so species of Passifloras are edible. Some have tiny fruit, some have quite soft leathery skin, one has a rind that can only be opened with a hammer, many are rather small, one, the size of a football, is too big. Even so, there are very nice flavored passionfruit with good handling characteristics, such as P. ligularis, that are never available commercially.

Although passionfruit are - or used to be - prolific fruiting common dooryard fruits in the countries whose climate allows them to grow and fruit, they are quite demanding as to climate and soil conditions. Consequently, the fruit appear on the market more or less as a luxury item.

Purple passionfruits have the third highest potassium level of any domestic fruit on these pages, at 348mg per100 grams.
They have useful amounts of vitamin A, at 700 International Units per 100 grams.