DI FU ZI - scoparia By Tony Harrison, Manager of the Bristol Chinese Herb Garden

BOTANY Di Fu Zi has been known by several Latin names over the years since it was first labelled as Chenopodium scoparium by in 1753. In 1809 it was placed in the genus by Heinrich Schrader and the is generally referred to as Kochia scoparia in most Chinese materia medica texts, despite the fact it was transferred to the genus Bassia in 1978 by Andrew Scott. This classification was confirmed by molecular phylogeny in 2011 and the official name is now . There are also many common names. In the gardening world it is often known as ‘burning bush’ and grown for its intense autumn colour.

Bassia scoparia changes from green to red as it sets seed.

The adulteration of Bassia seeds with the seed of Leonorus japonicus (Chong Wei Zi) has long been prevalent in Hong Kong and Guangdong. The action of these 2 herbs is quite different. Fortunately, they are easy to tell apart with a small hand lens. Benski also lists several other which can be present as adulterants and local substitutes. They include the related Chenopodium album used in many provinces of China. In the southern province of Guangxi, Baekea frutescens is used, and in Sichuan and Yunnan, Melliotus suavedens. Other Kochia species are also used in the far north including Kochia sieversiana. The specific name,’scoparia’ refers to the use of the plant as a sweeping broom.

PHARMACOGNOSY Because of the many possible sources, it is worth learning the identification morphology of this herb as given in the Chinese Pharmacopoeia which states the following description.

Seeds flattened ovoid 1mm, surrounded by a persistent perianth 1-3mm in diameter. The shape of the perianth is oblate-spheroid with 5 membranous winglets in the shape of a star. In the centre of the dorsal surface, the slightly prominent fruit stalk scar has 5-10 radial veins.

The distinguishing features of Di Fu Zi are the overall flattened spherical shape of the perianth surrounding the seed and presence of 5 ridges, giving it a star shape. As you can see from the photographs, the seed of Leonorus heterophyllus (Chong Wei Zi) is trihedral 2-3mm long with the seed narrowing towards one end.

Star shaped perianth seed casing is distinguishing feature of Di Fu Zi

Seeds of Chong Wei Zi have distinct trihedral shape

The size is also important as Chenopodium seeds tend to be smaller than the 3 mm achieved by Bassia and the perianth does not have the star shape. Seeds of Baeckae frutescens are small and within a bell shaped capsule and Mellotus suaveolens has seeds 3mm by 2mm covered by a net- like pattern and attached to a persistent hook- like fruit stalk. I have not seen these in the UK. Let me know if you have.

ETHNOBOTANY Bassia scoparia is a large annual herb in the family , which includes several other food based plants. Vast quantities of the seed have been sown by airplane to give quick groundcover for grasses and food for wildlife after fire, and to stabilise soil erosion. In some cases, this has caused problems of invasion. At least 10 different are used to eradicate Bassia as a naturalised weed in the USA. After it flowers it dies and breaks off at the base to become one of the varieties of seen in semi desert regions. There is little chance of it becoming a weed in our cold damp climate. It does have a use as a forage crop for livestock on dry lands, yielding hay which is high in crude protein. This use is, however, restricted by its toxicity to cattle in large doses. Livestock ingesting large amounts can experience weight loss, hyperbilirubinemia, photosensitisation and polyuria. In Japan it is used as a food source to create a garnish called ‘tonburi’ after boiling and removal of the seed coating. It was used as a famine food in China having been introduced from the Mediterranean some 2000 years ago. Pliny comments that it is mentioned as an aromatic herb in the medieval European herbals.

MEDICINAL USE The seed contains the triterpene saponin known as momordin lc which has been the subject of some study. Its anti rheumatoid action has led to its extraction as a drug. Momordin has also been shown to reduce the storage of fats in the body and also to protect the liver by increasing oxidative defence pathways. This chemical does appear to target the liver both in its positive effects and also in the overdose scenario with livestock. Momordin is, however, only one of over 12 triterpenes, 24 volatile oils, 2 alkaloids ( harman/harmine) and flavenoids found in the seed, so we should be cautious in linking its action solely to momordin saponins.

The energetics of the seed according to TCM is as a cold herb with pungent and bitter taste acting on KID/BL channels. It removes damp heat, especially from the bladder, and expels dampness and wind.

The seed is common in formulas for difficult and painful urine and for itching skin, especially eczema. Although in the category of drain dampness herbs, it acts by mobilising the exterior and hence it can also be employed to clear wind heat with symptoms of swollen painful eyes and dizziness. One folk use of the fresh juice of the leaves is to treat heat and pain in the eyes. Action as an exterior releasing herb is more than likely an effect of the volatile oils which would be much stronger if we use the fresh plant. The dose is 9-15g. The fresh herb is used in dosages 30-60g. It is a safe herb at these low dosages, although Benski does report occasional allergic reactions.

CULTIVATION As a rank weed, Bassia scoparia is very adaptable to its surroundings. It is not particular about soil, doing well in any average garden soil, but it does need good drainage. There are some seeds provided in this journal. Plant the seeds in moist soil as this is the trigger for germination in their typical arid habitat. Seedlings appear in about 10 days and they should be thinned to eventually about 2 foot centres. Or you can sow in individual pots if the soil is not yet warmed up and then transplant in April.

Seeds forming, but not yet ripe. Wait for the plant to die off.

The whole plant starts to turn red in the autumn and you should check for ripe seeds when the leaves die down. The whole plant is then cut down and dried. The seeds are later removed when dry by threshing. The seeds do not have a long life and they should be kept very dry and cool if you want to use them next year for planting.

REFERENCES Chinese Medical Herbology and Pharmacology J.Chen, T.Chen Art of Medicine Press 2001 ISBN 0-9740635-0-9

Chinese Materia Medica.; Chemistry, Pharmacology and Applications You Ping Zhu Harwood Academic Publishers 1998 ISBN 90-5702-285-0

Chinese Herbal Materia Medica: D.Benski, S.Clavey, E.Stoger Eastland Press 2004 ISBN 0-939616-4-24

Pharmacopoeia of the Peoples Republic of China Pharmacopoeia Commission of PRC 1992 Guandong Science and Technology Press ISBN 7-5359-0945

Serum Constituents and metabolic hormones in sheep and cattle fed Kochia scoparia hay. Rankins,D.L et al. Journal of Animal Science 69(7), 2941-46

Reduction in fat storage in mice fed a high-fat diet long term by treatment with saponins prepared from Kochia scoparia fruit. Han,L.K. et al (2006) Phytotherapy Research 20(10), 877-82

© Tony Harrison