Introduction to Perilla
Perilla is known by its botanical name, perilla frutescens and is a perennial plant in the mint family, Lamiaceae. The Perilla species encompasses two distinct varieties:
- Perilla frutescens var. crispa
- Perilla frutescens var. frutescens
Perilla frutescens var. crispa is the aromatic leafy herb. The plant occurs in red (purple-leaved) or green-leaved forms.
In various countries and cultures it is known by different names:
- Korean name is jasoyup, 자소엽
- Japanese name is shiso, 紫蘇 or シソ
- Chinese name is 紫蘇; pinyin: zĭsū; Wade–Giles: tsu-su
- English common name is “beefsteak plant”
Perilla frutescens var. frutescens is the source of perilla oil. The seeds contain 35 to 45 percent oil which is obtained by pressing. Perilla oil is a very rich source of the omega-3 fatty acid alpha-linolenic acid (ALA). About 50 to 60% of the oil consists of ALA.
How Various Cultures Use Perilla
The Asian cultures use perilla in its many forms throughout their cuisines and for its medicinal value.
In Korea, perilla is mainly cultivated in the provinces of Chungcheong, Gyeongsang, and Jeolla. In their cuisine, it is used for marinating namul (seasoned vegetable dish), coating grilled gim (Korean laver), or pan-frying jeon (pancake-like dish). In North Korea, it is called deulkkae gireum (들깨기름).
In China, perilla is called zǐsū:
- Simplified Chinese: 紫苏
- Traditional Chinese: 紫蘇
- Pinyin: zǐsū
The Chinese have used perilla traditionally in Chinese medicine.
The Japanese use the Perilla frutescens var. crispa in their cuisine and it is called shiso (紫蘇). The Japanese name for the green type of perilla is called aojiso (青紫蘇?), or ooba (“big leaf”), and is often combined with sashimi.
The purple leaf variety are called pak maengda (ຜັກແມງດາ) in Laos. They are usually strong in fragrance. The people of Laos use them is a rice vermicelli dish called khao poon (ເຂົ້າປຸ້ນ).
The Vietnamese use a variety of perilla with greenish bronze on the top face and purple on the opposite face. The leaves are smaller and have a much stronger fragrance. In Vietnamese, it is called tía tô, derived from the characters (紫蘇) whose standard pronunciation in Vietnamese is tử tô.
India and Nepal
In Nepal and parts of India, perilla is called silam (सिलाम), thoiding (Meitei), Chhawhchhi (Mizo) and bhangira.
Components of Perilla leaf, seeds and oil
Perilla seed oil has a high lipid content, with a range as high as 38-45% lipids.
Perilla oil has one of the highest content of omega-3 (α-linolenic acid (ALA) fatty acids of any seed oil. It also contains linoleic acid. omega-6 fatty acid. The proportions of omega-3 and omega-6 is as follows: 1
- Omega-3 54-64%
- Omega-6 14%
The Japanese variety of perilla, named shiso contains a lower percentage of lipids, at approximately 25.2-25.7% lipid content. Even though there is a lower percentage of lipids in the shiso variety, the α-linolenic acid (ALA) content is approximately 60% of the total lipids.
Perilla also contain certain essential oils, such as: 2
Korean scientists found a number of aroma-active compounds from Korean perilla (Perilla frutescens Britton). Thirty-three volatile compounds were identified by GC-MS. The most important of these volatile compounds include: 3
- I-(3-Furyl)-4-methyl-1-pentanone (perilla ketone) was found to be the most abundant volatile compound
Perilla ketone comprised 81% (93 ppm), 84% (120 ppm), and 95% (490 ppm) of the volatile compounds obtained from SAFE, LLCE, and HD, respectively.
The organic acids found in perilla are:
- Ferulic Acid
- Rosmarinic Acid
The polyphenols in perilla have been identified as:
- Luteolin (17.3mg/gram)
Health Benefits of Perilla
There are a number of research studies on the effect of perilla leaf and oil on certain health conditions. These studies and their abstracts are listed in the Table below:
Medicinal Value of Perilla Leaf, Seed and Oil
Condition Abstract Reference
Inflammation Triterpene acids from the leaves of Perilla frutescens and their anti-inflammatory and antitumor-promoting effects 1
Liver cancer Growth inhibitory and apoptosis inducing effect of Perilla frutescens extract on human hepatoma HepG2 cells. The results of our study suggest that the PLE should be further investigated as a promising to treat hepatocellular carcinoma. 2
Colon cancer We have investigated the modulatory effect of dietary perilla oil which is rich in the n-3 polyunsaturated fatty acid, alpha-linolenic acid, on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) in male F344 rats. Marked increases in n-3 polyunsaturated fatty acids in membrane phospholipid fractions and decreased PGE2 levels were observed in colonic mucosa of perilla oil-fed rats. These results suggest that perilla oil, even in small amounts, suppresses the development of aberrant crypt foci, and is therefore a possible preventive agent in the early stage of colon carcinogenesis. 3
Tumor necrosis factor-alpha (TNF-alpha) inhibitor The overproduction of tumor necrosis factor-alpha (TNF-alpha) was suppressed by orally administering a perilla leaf extract (PLE). When mice were successively injected with OK-432, severe TNF-alpha was induced in the serum, but this elevated TNF-alpha level was reduced after an oral administration of PLE (400 microliters/mouse). 4
Allergies Perilla extract significantly suppressed the PCA-reaction, which was brought about by rosmarinic acid with a partial contribution from some macromolecular compounds. The anti-allergic titer of rosmarinic acid was more effective than tranilast, which is a modern anti-allergic drug. Perilla and rosmarinic acid are potentially promising agents for the treatment of allergic diseases. 5
Blood clotting As compared with high dietary linoleate safflower oil, high dietary alpha-linolenate perilla oil decreased platelet-activating factor (PAF) production by nearly half in calcium ionophore (CaI)-stimulated rat polymorphonuclear leukocytes (PMN). In the CaI-stimulated PMN from the perilla oil group, the accumulated amount of arachidonate (AA) plus eicosapentaenoate (EPA) was 30% less and that of lyso-PAF was 50% less, indicating that the decreased availability of lyso-PAF is a factor contributing to the relatively low PAF production. 6
Ulcerative colitis The DSS-treated rats were fed either a perilla oil-enriched diet (perilla group) or a soybean oil-enriched diet (soybean group). The bradykinin-stimulated DeltaIsc in the soybean and perilla groups was significantly higher than that in the control group. The mucosal level of arachidonic acid in the perilla group was significantly lower than that in the soybean group. results suggest that supplementation with alpha-linolenic acid, in combination with a lipoxygenase inhibitor, could suppress the increase in Cl- secretion in patients with ulcerative colitis (UC). 7
Learning Donryu strain rats through two generations were fed semi-purified diets supplemented with safflower seed oil (rich in linoleic acid) or with perilla seed oil (rich in alpha-linolenic acid), or a conventional laboratory chow (normal control diet). Brightness-discrimination learning ability was determined to be the highest in the perilla oil-fed group, followed by the normal group, and then by the safflower group, extending our earlier observation in a different strain of rat that alpha-linolenic acid is a factor in maintaining high learning ability 8
Asthma Perilla seed oil (5 - 500 microg/mL) inhibited the slow reaction substance of anaphylaxis (SRS-A) release induced by antigen challenge in lung tissue of sensitized guinea pigs. It also inhibited calcium ionophore (A(23187))-induced leukotriene (LT) D4 release from the lung tissue of non-sensitized guinea pigs in a concentration-dependent manner with an IC50 (95 % CI) of 50 (36 - 69) microg/mL. These results indicate that Perilla seed oil may improve lung function in asthma by controlling eicosanoid production and suppressing LT generation. 9
Fatty acid synthase suppression This study was performed to determine the effects of dietary perilla oil, a n-3 alpha-linolenic acid (ALA) source, on hepatic lipogenesis as a possible mechanism of lowering triacylglycerol (TG) levels. The activities of hepatic lipogenic enzymes such as fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase, and malic enzyme were suppressed in the fish oil, perilla oil, and corn oil-fed groups, and the effect was the most significant in the fish oil-fed group. 10