Ferns are ancient plants that have continuously evolved till today. A fern is a member of a group of approximately 250 genes, over 12,000 species, mostly grown in high-humidity tropical area but can also be found in subtropical and cold climate. Ferns are lower vascular plants that have neither seeds nor flowers, reproduce via spores and rely on water to sustain life cycle. Edible and herbal, ferns are also the queen of ornamental plants for their beautifully-shaped and colorful leaves lending to their popularity.

One of Thai ferns is called Cyclosorus terminans (or Amphineuron terminans or Thelypteris terminans, Thelypteridaceae family), which has similar characteristics as vegetarian ferns, native to southern Thailand in the Thelypteridaceae family like T. ornata and T. truncate. Young Cyclosorus terminans has edible tips. They often grow on a moist, shady soil under a big tree but without too much variation in temperature. They prefer high humidity, sandy soil and dry escarpment at 600-1200 meters above sea level. In Thailand, ferns are reportedly found in provinces of Nan, Sakol Nakorn, Chacheng Sao, Trad, Kanjanaburi, Nakhon Sri Thammarat and Songkhla.

The preliminary study by Asst. Prof. Dr. Sireewan Wiriyagulopas from the Department of Pharmacognosy and Pharmaceutical Botany of the PSU Faculty of Pharmacy, found that extracts from Fern Cyclosorus terminans contain antibacterial property toward gram-positive bacteria, which include Methicillin-sensitive Staphlococcus aureus (MSSA), Methicillin-resistant S. Aureus, S. epidermidis and Bacillus subtillis, withinterruptin as an active ingredient. This discovery leads to a process of green extraction, an environmentally-friendly method, to extract high concentration of interruptin from Cyclosorus terminans, in both water-soluble and oil-soluble form, to produce antibacterial soap products that are safe and environmentally friendly.