Diplazium esculentum

Diplazium esculentum, the vegetable fern, is an edible fern found throughout Asia and Oceania. It is probably one of the most commonly consumed ferns.

The genus Diplazium is in the family Athyriaceae, in the eupolypods II clade of the order Polypodiales, in the class Polypodiopsida.

Description
This plant is a large perennial fern with an ascending rhizome of about 50cm high and covered with short rufous scales of about 1mm long. The plant is bipinnate with long brownish petioles, and the petiole base is black and covered with short scales. The frond can reach 1.5m in length, and the pinnae is about 8cm long and 2cm wide.

Uses
The young fronds are stir-fried and used in salads.

They may have mild amounts of fern toxins but no major toxic effects are recorded.

It is known as  pakô ("wing") in the Philippines, pucuk paku and paku tanjung in Malaysia, sayur paku or pakis in Indonesia, phak koot (ผักกูด) in Thailand, rau dớn in Vietnam, dhekia (ঢেকীয়া) in Assam, Dhenki Shaak (ঢেঁকি শাক) in Bengali, paloi saag in Sylheti, ningro in Nepali, dingkia in Boro and linguda in northern India, referring to the curled fronds.

It is known as pohole or hō'i'o in Hawaiian cuisine. The ferns grow in wet areas of shady valleys. The fern species Diplazium esculentum is believed to have been introduced and naturalized in Hawaii and was first reported collected in 1910. The fern also has medicinal uses.

Pharmacological effects
The extract also had alpha-glucosidase inhibitory activity.