Perilla: Shiso vs. Oba leaves
Shiso (シソ/紫蘇) is an annual plant that belongs to the genus Perilla in the family Lamiaceae, and probably because of that, it is referred to as perilla in English.
Shiso vs. Oba
The leaf is edible with a fresh, herby fragrance, and in Japanese food culture, it serves as an accent in dishes.
The plant Shiso comes in various varieties, but they are broadly classified into two groups based on the color of the leaf.
One is Akajiso (赤ジソ) with red leaves, while the other is Aojiso (青ジソ) with green leaves.
Meanwhile, Aojiso is a potherb typically used in Tempura and Oba Miso and prepared for Sashimi as a garnish.
Aojiso or green Shiso leaves have another name Oba (大葉), which literally means big leaf in Japanese.
But big leaves of Akajiso or red Shiso are not called Oba. Only the picked Aojiso leaves served as food are allowed to be called Oba.
(Reference Page: Wikipedia シソ )