The form most commonly used at the moment is the perilla seed defatted extract; however, this review will also include information regarding other forms.
Phase I clinical trials have shown a favourable toxicity profile and preliminary data have indicated somechemotherapeutic efficacy in advanced cancers. However, perillyl alcohol (1200 mg/m2 four times daily) failed to extend the time-to-progression in three phase II studies in patients with advanced ovarian carcinoma, prostate cancer and colorectal cancer. All trials were very small and had to contend with high drop-out rates due to intolerabihty of the medicine. Despite encouraging preclinical results, perilla does not appear to be an effective treatment for advanced cancer.
Based on traditional use, in vitro and in vivo studies, and human trials, perilla leaf and defatted seed extracts are used for allergic respiratory disorders including hay fever, asthma and sinusitis. The refined oil may also help allergic and inflammatory respiratory conditions by regulating the arachidonic acid metabolism pathways.
A double-blind, randomised, placebo-controlled clinical trial showed a significant reduction in symptoms such as watery eyes, itchy eyes and itchy nose in 29 patients with seasonal allergic rhinoconjunctivitis, taking 50 or 200 mg of rosmarinic acid enriched perilla for 21 days. Responder rates were 55.6% and 70%, respectively. A drastic reduction in the number of neutrophils and eosinophils in nasal fluid was also demonstrated.
An open clinical trial of 20 human subjects suffering allergic symptoms, including sneezing, nasal obstruction and itchy eyes and skin, were treated with 100-150 mg perilla seed extract daily (higher dose for persons over 60 kg) for 2 weeks. The subjects themselves evaluated changes in the severity of symptoms. Significant improvement was noted in 80% of the subjects for nasal obstructive symptoms, 40% reported a significant improvement in sneezing, and half reported a significant reduction of itchy eyes.
Perilla leaf extract cream
Open studies of more than 100 children with atopic dermatitis found that perilla leaf extract cream improved symptoms in 80% of cases after 3 months’ treatment. Another open study with 20 allergic patients, using perilla leaf cream topically and perilla leaf extract orally, showed a general improvement in 90% of the patients after 2 months, with 30% reporting significant improvements.
DENTAL CARIES AND PERIODONTAL DISEASE
Perilla seed extract inhibits the growth of cariogenic and inflammatory microorganisms including oral streptococci and Porphyromonas gingivalis. Perilla seed extract also reduces inflammation through inhibition of leukocyte production and radical scavenging activity. As such, application of the extract in the oral cavity is used to reduce dental caries and pericoronitis.
Perilla: Other Uses
Perilla refined oil is a good source of n-3 series alpha-linolenic acid.
Clinical note — Perilla and TCM
Perilla is an important ingredient of several TCM formulas. Perilla leaf is a key ingredient in Saiboku-to, a traditional Chinese formulation used in the treatment of type 1 hypersensitivity disorders including asthma. Saiboku-to contains Bupleurum falcatum, Pinellia ternata, Poria cocus, Scutellaria baicalensis, Magnolia officinalis, Zizyphus spinosa, Panax ginseng, Glycyrrhizae uralensis, Zingiber officinale and perilla.
Banxia Houpu Decoction used for depression. It contains Pinellia ternata, Poria cocos, Magnolia officinalis, Perilla frutescens and Zingiber officinale.
Perilla: Dosage Range
• Perilla leaf: extract equivalent to 4-9 g/day.
• Perilla refined oil: 1000 mg capsules taken 3-6 times daily.
• Perilla seed extract (containing min. 3.0% polyphenols): 100-1 50 mg/day.
• External use (dental caries and periodontal disease): 80-160 mg defatted perilla seed daily delivered directly into the oral cavity in the form of toothpaste, chewing gum or mouth rinse.