490 Handbook of herbs and spices
which is essential in maintaining health. Feeding trials have shown that Perilla oil
reduced levels of cholesterol, phopsholipids and triglycerols in the blood (Nanjo
et al., 1993). Perilla oil diet also reduces the level of arachidonic acid, a precursor of
prostaglandin biosynthesis by 67%. The production of prostaglandin E 2 in kidney is
reduced by 75% in the case of Perilla oil-fed rats.
Perilla in the treatment of allergy
Allergy is the most widespread immunological disorder in humans, and is regarded
by health experts as the most rapidly increasing chronic health problem. Investigations
have shown that cytokines such as the tumour necrosis factor (TNF) are constantly
associated with allergic reactions. Plasma TNF level becomes elevated in the serum
of patients with atopic dermatitis and the level is tightly correlated with plasma
histamine (Cooper 1994; Sumimoto et al., 1992). The treatment of allergy depends,
in addition to allergy avoidance, on antihistamines, corticosteroids, sodium
chromoglycate, etc., and is only symptomatic in approach. In Chinese traditional
medicine, Perilla and its products are used very successfully for allergy treatment.
Many reports (Oyanagi, 1997; Yamagata, 1992; Mitsuki, 1992; Kabaya, 1994) indicated
that administration of Perilla extract – orally, nasally and topically – can relieve the
allergy symptoms. The treatment period ranges from one week to three months, and
the effect remains for substantially long periods. Chemical studies carried out by
Japanese workers (Okabe, 1990; Okuhira, 1993; Oyanagi, 1997) were quite
promising, and 73.5% and 80.6% of the patients in two test groups showed significant
improvement. The use of Perilla in the treatment of allergy has been reviewed by Yu
et al. (1997).
29.5.2 Perilla as a spice
Perilla leaves are strongly aromatic with a strong mint flavour, and having a pleasant,
sweet taste. Perilla leaves are used as a spice, cooked as potherbs or fried and
combined with fish, rice, vegetables and soups. It is also chopped and mixed with
ginger rhizome and then added to stir-fries, tempuras and salads in many Asian
countries. It is most widely used in Japanese, Korean, Vietnamese, Thai and Chinese
cuisines. In India it is used in the north-eastern regions. The purple variety is used to
impart colour along with flavour to many pickled dishes, the most famous of such
dishes being the Japanese pickled plum. Perilla leaf extract was once the most
important ingredient in sarsaparilla. It is also used to flavour dental products. The
entire plant is very nutritious and is a rich source of vitamins. In Vietnam and Korea
Perilla leaves are used as a fragrant garnish to noodle soup and spring rolls. In these
countries it is the essential flavouring ingredient in dog meat soup (known as Bosintang),
in which the Perilla leaves not only suppresses the meat smell, but also add flavour
and colour (Anon. 2005).
In Japan, Perilla is one of the most widely used flavouring herbs. Perilla is believed
to detoxify the toxic principles of shellfish and other crustaceans and hence is an
essential ingredient in all such dishes. Perilla leaves are used to garnish ‘Sashimi’,
the famous Japanese raw fish dish. It is also used in tempuras, a dish of seafood deep
fried in sesame oil. Perilla leaves are very widely used in pickling Japanese plum, the
product is known as ‘Umeboshi’. For this, unripe fruits are harvested, packed with
red Perilla leaves and pickled. The anthocyanin in the leaves imparts an attractive red
colour and flavour to the plum. Umeboshi is traditionally served with Tofu, the sea