An Unlikely Treasure

A work friend of mine gave me a start a few years back of a rather ordinary purple leafed plant..or at least it seemed. I planted it in my garden thankful for any new and different addition.. then to be honest I kind of forgot it. Each year it seemed to spread more and more. I soon realized this must be a aggressive self sower..for sure. This year the unknown purple plant has returned with avengence. I mean it's everywhere..adding a nice touch of purple color to the landscape. The plant itself looks alot like a coleus..and flowers in a similar fashion. I was at the herb farm a few weekends ago and I saw that unknown plant growing in one of the herb farm gardens.. I of course inquired as to its name. I was informed that the unknown purple plant is Perilla..Then the other day when I was looking up some information on plants for my new herb garden...smile more on that later!!! I came acrossed the purple plant again...and this time it was listed as Sweet Herb, great for cooking..hmmm. How could I have not ever heard about this little treasure. Yesterday while working in the garden I rubbed the leaves and discovered the delightful scent!!! It's a mixture between sweet and licorice flavor. I also found out that while crushing the leaves in a hot sweaty hand that the leaf omits a lovely purple dye...wow!!! Today I'm on the net finding out just what this Perilla is all about?? Who Knew!!

Perilla Leaf, Seed, and Stem

by Subhuti Dharmananda, Ph.D., Director, Institute for Traditional Medicine, Portland, Oregon

Perilla is a mint plant (Laminaceae Family), Perilla frutescens, growing in the hills and mountains of East Asia (mainly India, China, Japan, and Korea). It has been spread around the globe during the previous century; initially it was desired as a decorative garden plant, but then it escaped cultivation; as an example, it now grows in spots throughout most of the Eastern and Midwestern United States, described as an invasive weed. The plant has long been used as a source of herb materials for Chinese medicine; it is known in China as zisu. The character zi refers to the distinctive purple color of the stem; in some varieties or under certain growing conditions, the leaves also display a red-purple coloration; green leaves are more commonly found, while some varieties have one side of the leaf being green and one side red-purple. The character su means comfort, and refers to the comforting effect of perilla leaves when taken as a tea. Two parts of the plant are commonly used in Chinese medicine: the leaf (ye) and the seed (zi), respectively called zisuye and zisuzi (or Zi Su Ye and Zi Su Zi); some herbalists use the stem separately or mixed with the leaves. Jiao Shude has a good description of the different plant parts.

Perilla is also used as a food source (2). The crispa variety of perilla, which has “crisped” leaves (curled along the edges), is known in Japan as shiso leaf (or jiso; this is the Japanese version of the word zisu), used in preparing some sushi dishes and in making pickled plums (umeboshi). The leaves of perilla are used as a garnish or flavoring for some Vietnamese dishes. In China, Hunan cuisine may include perilla leaves in preparing fish. The seeds are used in Japan as a source of oil for cooking, and this oil has been developed as a specialty health product marketed internationally because it is rich in omega-3 fatty acids. Perilla seed is used in making some Indian curries. The seeds are a major food in Korea, used plain and roasted, as well as a source of cooking oil; annual production of perilla seeds in Korea is about 40,000 metric tons.

Perilla Leaf

In the modern Chinese Materia Medica, perilla leaf is categorized as a surface-relieving herb used for common cold and similar types of acute disorders that might involve stuffy nose, cough, and headache; it is considered best for treating “wind-cold” type disorders, and is classified as pungent and warm. Perilla leaf (and especially the stem) is also considered valuable for dispersing stagnant qi and calming the mind. This dual use is also noted for bupleurum (chaihu), classified as a surface relieving herb but commonly employed for regulating qi and calming the mind; a combination of bupleurum, perilla leaf, curcuma, and acorus is used for treating depression. Other surface relieving herbs are sometimes used by Chinese doctors as qi-regulating herbs, such as siler (fangfeng) included in Tong Xie Yao Fang, and mentha (bohe) included in Xiao Yao San. 

Perilla leaf is aromatic, with main active ingredients being volatile oils dominated by monoterpenes (3). Among these components are perillaldehyde (the major flavor and fragrance constituent; structure shown left), perillene, β-caryophyllene, thujopsene, β-farnesene, limonene, elsholtziaketone, perillaketone, furylketone, linalool, and trans-citral. The leaves also contain some larger molecules as active components, such as ursolic acid (a triterpene glycoside) and rosmarinic acid (structure shown right). The red-purple coloration of the stem (and leaves, when so-colored) has been attributed to anthocyanins and flavones, such as luteolin; a specially prepared perilla extract rich in these compounds is sold as a food color for beverages, jams, and candies; it is red in acid pH (but green at basic pH).