ISO 20255:2026

International
Standard
ISO 20255
First edition
Traditional Chinese medicine —
2026-09
Epimedium brevicorum, Epimedium
sagittatum, Epimedium pubescens,
and Epimedium koreanum herb
Médecine traditionnelle chinoise — Plantes Epimedium
brevicorum, Epimedium sagittatum, Epimedium pubescens et
Epimedium koreanum
Reference number
© ISO 2026
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Descriptions . 2
4.1 Epimedium brevicornu Maxim. .2
4.2 Epimedium sagittatum (Sieb.et Zucc.) Maxim. .2
4.3 Epimedium pubescens Maxim. .2
4.4 Epimedium koreanum Nakai .2
5 Requirements and recommendations . 7
5.1 General characteristics .7
5.2 Microscopic characteristics .7
5.3 Moisture .9
5.4 Total ash .9
5.5 Ethanol-soluble extractives .9
5.6 Thin-layer chromatogram (TLC) identification .9
5.7 Marker compounds .9
5.8 Heavy metals .9
5.9 Pesticide residues .9
5.10 Foreign matter .9
6 Sampling . 9
7 Test methods . 10
7.1 Macroscopic identification .10
7.2 Microscopic identification .10
7.3 Determination of moisture .10
7.4 Determination of total ash .10
7.5 Determination of ethanol-soluble extractives .10
7.6 Thin-layer chromatogram identification .10
7.7 Determination of marker compounds .10
7.8 Determination of heavy metals .10
7.9 Determination of pesticide residues .10
8 Test report .10
9 Packaging, storage and transportation .11
10 Marking and labelling .11
Annex A (informative) Thin-layer chromatogram (TLC) identification .12
Annex B (informative) Determination of marker compounds .15
Annex C (informative) Reference information of national and regional requirements on
Epimedium herb . 17
Bibliography . 19

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 249/SC 1, Traditional medicine, Subcommittee
SC 1, Traditional Chinese medicine.
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iv
Introduction
The genus Epimedium belongs to the family Berberidaceae. It has more than 50 species, distributed in North
Africa, northern Italy to the Black Sea, Western Himalayas, Northeast Asia including Korea, Japan, and
part of China. Epimedium is a typical forest plant. In nature, plants of this genus form dense thickets and
bloom on humus-rich, slightly moist soil under the canopy of foothill forests, where the young foliage fully
obscure the sun. They are not tolerant direct sunlight, especially in hot summer. Even in the spring, except
in the morning and evening, their leaves can get burned when exposed to direct sunlight. Therefore, when
planting Epimedium, it is desirable to create the conditions similar to their natural habitat and to place them
in the shade or partial shade from tall trees and shrubs. China is the geographical distribution centre of
Epimedium, where nearly 40 species are found, comprising over 80 % of the genus.
In China, Epimedium herb (known as “Yin Yang Huo”) mainly includes four species, Epimedium brevicornu
Maxim., Epimedium sagittatum (Sieb.et Zucc.) Maxim., Epimedium pubescens Maxim. and Epimedium koreanum
Nakai. Epimedium koreanum Nakai is also distributed in North Korea, Japan, Russia, and Italy.
Modern pharmacological studies show that Epimedium herb has various bioactivities, including anti-
aging, antitumor, anti-depression and anti-osteoporosis effects. It can also enhance immunity, promote
hematopoiesis, increase cardiovascular flow, and regulate bone metabolism.
As national implementation can differ, national standards bodies are invited to modify the values given in
5.3, 5.4 and 5.5 in their national standards. Examples of national and regional values are given in Annex C.

v
International Standard ISO 20255:2026(en)
Traditional Chinese medicine — Epimedium brevicorum,
Epimedium sagittatum, Epimedium pubescens, and Epimedium
koreanum herb
1 Scope
This document specifies the minimum requirements and test methods for wild and cultivated Epimedium
herb.
This document applies to Epimedium herb that is sold and used as natural medicines in international trade,
including Chinese materia medica (whole medicinal materials) and decoction pieces derived from this plant.
2 Normative references
The following documents are referred to in the text in such a way that some or all their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 18664, Traditional Chinese Medicine — Determination of heavy metals in herbal medicines used in
Traditional Chinese Medicine
ISO 21310, Traditional Chinese medicine — Microscopic examination of medicinal herbs
ISO 21371, Traditional Chinese medicine — Labelling requirements of products intended for oral or topical use
ISO 22217, Traditional Chinese medicine —Storage requirements for raw materials and decoction pieces
ISO 22258, Traditional Chinese medicine — Determination of pesticide residues in natural products by gas
chromatography
ISO 23723, Traditional Chinese medicine — General requirements for herbal raw material and materia medica
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
Epimedium herb
terrestrial part or leaves of Epimedium brevicornu Maxim., Epimedium sagittatum (Sieb.et Zucc.) Maxim.,
Epimedium pubescens Maxim., and Epimedium koreanum Nakai (Fam. Berberidaceae)

4 Descriptions
4.1 Epimedium brevicornu Maxim.
Leaf of Epimedium brevicornu is ternately compound. Leaflets are oval in shape, 3 cm to 8 cm in length and
2 cm to 6 cm in width. The apex of leaflet is acuminate. The terminal leaflet is cordate at the base. Bilateral
leaflets are small and oblique cordate. The outer side of the leaf is large and auriculate. The margin of the
leaf is yellow and thorny serrulation. (see Figure 1 A).
The upper surface of the leaflet is yellowish-green, and the lower surface is greyish-green. There are 7 to 9
main veins, with sparsely covering slender hairs at the base. Both surfaces have prominent secondary thin
veins and distinct, reticulated veins. The petiolule is 1 cm to 5 cm in length. The texture is close to leathery.
It has a slight characteristic odour and a slightly bitter taste.
4.2 Epimedium sagittatum (Sieb.et Zucc.) Maxim.
Leaf of Epimedium sagittatum is ternately compound. Leaflets are ternately compound, long-ovoid to ovoid-
lanceolate, 4 cm to 12 cm in length, 2,5 cm to 5 cm in width, with acuminate apices. Bilateral leaflets are
distinctly oblique at the base and their outer sides are mostly arrow-shaped. The lower surface of the leaf
lamina is sparsely covered with thick, short pronated hairs or nearly glabrous. The lamina is leathery (see
Figure 2A).
4.3 Epimedium pubescens Maxim.
Leaf of Epimedium pubescens is ternately compound. The leaflets are 3 to 20 cm in length and 2 cm to 8 cm
in width. The upper surface of the leaflet is dark green to brownish-green and glabrous, with a papery and
coriaceous texture. The lower surface of the leaflet is pale green to greenish-grey. The petioles are densely
covered with flossy pubescence. The lamina of the leaflet is ovate or narrowly ovate to lanceolate with a
serrulate, spiny margin. The apex of the leaflet is acuminate or shortly acuminate. (see Figure 3 A).
4.4 Epimedium koreanum Nakai
Leaf of Epimedium koreanum is ternately compound. Leaflets are relatively large, 4 cm to 10 cm in length,
3,5 cm to 7 cm in width. The upper surface of the leaflet is dark green with
...