ISO 25662

• Abstract:

  This proposal specifies minimum requirements and test methods for Leonurus japonicus herb [the dried aerial part of Leonurus japonicus Houtt.]. It is applicable to Leonurus japonicus herb that is sold and used as a natural medicine in international trade, including Chinese materia medica (whole medicinal materials) and decoction pieces derived from the plant.

• Status: Not Published
• ICS: 11.120.10 - Medicaments
• Technical Committee: ISO/TC 249 - Traditional Chinese medicine
• Drafting Committee: ISO/TC 249/WG 1 - Quality and safety of raw materials and traditional processing
• Current Stage: 6000 - International Standard under publication
• Start Date: 11-Sep-2026
• Completion Date: 19-Sep-2026

Overview

ISO 25662: Traditional Chinese Medicine - Leonurus japonicus Herb is an international standard developed by ISO for the quality and testing of Leonurus japonicus herb, commonly known as Chinese motherwort or "Yimucao." This standard establishes minimum requirements and specifies standardized test methods for the dried aerial parts of Leonurus japonicus Houtt. used in traditional Chinese medicine (TCM). It applies to materials traded globally, including both raw herbal forms (materia medica) and decoction pieces derived from this widely-used medicinal plant.

By harmonizing requirements across countries, ISO 25662 supports the safe and effective international trade of Leonurus japonicus herb. It provides guidance to farmers, manufacturers, importers, exporters, regulatory authorities, and healthcare professionals to ensure product authenticity, quality, and safety.

Key Topics

• Quality and Safety Requirements
  ISO 25662 details critical parameters for Leonurus japonicus herb, including:

  • Cleanliness and absence of foreign matter
  • Morphological features, such as color and texture
  • Microscopic structure for plant authentication
  • Moisture limits to ensure proper drying and prevent spoilage
  • Total and acid-insoluble ash content for purity assessment
  • Acceptable maximum levels for heavy metals (arsenic, cadmium, lead, mercury)
  • Pesticide residues in accordance with international safety guidelines
  • Measurement of water-soluble extractives
  • Quantification of marker compounds (stachydrine hydrochloride, leonurine hydrochloride) for quality verification

• Testing and Identification Methods
  The standard prescribes:

  • Macroscopic and microscopic identification
  • Thin-layer chromatography (TLC) for species authentication
  • Reference methods for moisture, ash, heavy metals, and extractive content
  • High-performance liquid chromatography (HPLC) for marker compound determination

• Packaging, Storage, and Labelling
  Guidelines ensure product protection and traceability:

  • Odour-neutral, safe packaging
  • Controlled storage to prevent contamination and degradation
  • Transport conditions to maintain quality
  • Labelling requirements, including product identity, net mass, origin, batch details, and specific quality features

• Sampling and Reporting
  Standardized procedures for sampling and reporting support regulatory compliance and traceability in international trade.

Applications

ISO 25662 has wide practical relevance across the herbal medicine supply chain:

• Manufacturers apply the standard to control and verify the quality of Leonurus japonicus raw materials and processed products, ensuring international acceptability.
• Traders and exporters use ISO 25662 to demonstrate compliance with global quality and safety parameters, facilitating smoother cross-border transactions.
• Regulatory authorities employ this standard as a basis for inspection, market surveillance, and import/export certification.
• Pharmacies and healthcare practitioners gain confidence in the safety, efficacy, and authenticity of the herbal product being dispensed or prescribed.
• Consumers benefit from improved transparency, consistent quality, and reduced risk of contaminants in herbal products.

Related Standards

ISO 25662 references and complements several other important standards in the field of herbal and traditional Chinese medicine:

• ISO 18664: Determination of heavy metals in herbal medicines used in TCM
• ISO 19609-2: Identity testing of herbal constituents
• ISO/TS 21310: Microscopic examination of medicinal herbs
• ISO 21371: Labelling requirements for products intended for oral or topical use
• ISO 22217: Storage requirements for raw materials and decoction pieces
• ISO 22258: Determination of pesticide residues in natural products by gas chromatography
• ISO 23723: General requirements for herbal raw material and materia medica

Adhering to ISO 25662 in combination with these related standards enables a consistent, safe, and internationally recognized approach to the management of Leonurus japonicus herb in the global herbal medicine industry.

FINAL DRAFT
International
Standard
ISO/FDIS 25662
ISO/TC 249/SC 1
Traditional Chinese medicine —
Secretariat: SAC
Leonurus japonicus herb
Voting begins on:
2026-07-16
Voting terminates on:
2026-09-10
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
ISO/FDIS 25662:2026(en) © ISO 2026

FINAL DRAFT
ISO/FDIS 25662:2026(en)
International
Standard
ISO/FDIS 25662
ISO/TC 249/SC 1
Traditional Chinese medicine —
Secretariat: SAC
Leonurus japonicus herb
Voting begins on:
Voting terminates on:
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2026
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/FDIS 25662:2026(en) © ISO 2026

ii
ISO/FDIS 25662:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Descriptions . 2
5 Quality and safety requirements and recommendations . 3
5.1 General characteristics .3
5.2 Morphological features .3
5.3 Identification .3
5.3.1 Microscopic identification . . .3
5.3.2 Thin-layer chromatography (TLC) identification .4
5.4 Moisture .5
5.5 Total ash .5
5.6 Acid-insoluble ash .5
5.7 Heavy metals .5
5.8 Pesticide residues .5
5.9 Water-soluble extractives .5
5.10 Marker compounds .5
6 Sampling . 5
7 Test methods . 5
7.1 Macroscopic identification .5
7.2 Microscopic identification .5
7.3 Thin-layer chromatography (TLC) identification .5
7.4 Determination of moisture content .5
7.5 Determination of total ash content .5
7.6 Determination of acid-insoluble ash content .6
7.7 Determination of heavy metals .6
7.8 Determination of pesticide residues .6
7.9 Determination of water-soluble extractives .6
7.10 Determination of marker compounds .6
8 Test report . 6
9 Packaging, storage and transportation . 6
10 Marking and labelling . 6
Annex A (informative) Thin-layer chromatography (TLC) identification . 8
Annex B (informative) Determination of stachydrine hydrochloride by HPLC-ELSD .10
Annex C (informative) Determination of leonurine hydrochloride by HPLC-UV .12
Annex D (informative) Reference information of national and regional requirements . 14
Bibliography .16

iii
ISO/FDIS 25662:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 249, Traditional medicine, Subcommittee SC 1,
Traditional Chinese medicine.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/FDIS 25662:2026(en)
Introduction
Leonurus japonicus herb, the dried aerial part of Leonurus japonicus Houtt., is widely used as an herbal
medicine in China and many countries. It is also known as “Yimucao” and Chinese motherwort.
In traditional Chinese medicine, this herb can activate the blood, regulate menstruation, and disperse
swelling, and is used for the treatment of irregular menstruation, dysmenorrhea, anxiety, and depression.
The market, yield, and trade volume of Leonurus japonicus herb is large, and has been developing rapidly in
recent years.
[1]
Leonurus japonicus herb has been recorded in several pharmacopoeias, including Chinese Pharmacopoeia ,
[2] [3] [4]
Japanese Pharmacopoeia , Korean Pharmacopoeia , European Pharmacopoeia , and Hong Kong Chinese
[5]
Materia Medica Standards . The requirements and specifications in these standards have differences.
Therefore, it is important to develop an international standard for Leonurus japonicus herb to harmonize
the existing standards, as well as ensure the safety and effectiveness of this herb. This document benefits
farmers, consumers, enterprises and governments involved in the cultivation, regulation and trade of
Leonurus japonicus herb.
As national implementation can differ, national standards Bodies can modify the values given in 5.4 and 5.5
in their national standards. Examples of national and regional values are given in Annex D.

v
FINAL DRAFT International Standard ISO/FDIS 25662:2026(en)
Traditional Chinese medicine — Leonurus japonicus herb
1 Scope
This document specifies the minimum requirements and test methods for Leonurus japonicus herb.
This document applies to Leonurus japonicus herb when traded and used internationally as natural medicine,
including both the raw 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 of 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 19609-2, Traditional Chinese medicine — Quality and safety of raw materials and finished products made
with raw materials — Part 2: Identity testing of constituents of herbal origin
ISO/TS 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 terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1
Leonurus japonicus herb
dried aerial part of Leonurus japonicus Houtt.
3.2
marker compound
chemical constituent within a medicinal herb that can be used to verify its quality
Note 1 to entry: Active ingredients or chemical markers used to confirm the botanical identity of the starting material.
Note 2 to entry: There may be one or more marker compounds f
...

Formatted: French (France)
ISO/DISFDIS 25662
Formatted: French (France)
ISO/TC 249/SC 1
Secretariat: SAC
Date: 2026-04-2107-02
Traditional Chinese medicine — Leonurus japonicus herb
DISFDIS stage
VVVoootttiiing bng bng beeegigiginsnsns o o on:n:n: 202 202 202555---111111---242424
VoVoVotintintinggg t t terererminminminatatateseses o o onnn:::  222000222666---000222---161616

ISO/DISFDIS 25662:2026(en)
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Formatted: French (France)
E-mail: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
ISO/DISFDIS 25662:2026(en)
Contents
Foreword . iii
Introduction . iii
Scope . iii
Normative references . iii
Terms and definitions . iii
Descriptions . iii
Quality and safety requirements and recommendations . iii
General characteristics . iii
Morphological features . iii
Identification . iii
Moisture . iii
Total ash . iii
Acid-insoluble ash . iii
Heavy metals . iii
Pesticide residues . iii
Water-soluble extractives . iii
Marker compounds . iii
Sampling . iii
Test methods . iii
Macroscopic identification . iii
Microscopic identification . iii
Thin-layer chromatography (TLC) identification . iii
Determination of moisture content . iii
Determination of total ash content . iii
Determination of acid-insoluble ash content . iii
Determination of heavy metals . iii
Determination of pesticide residues . iii
Determination of water-soluble extractives . iii
Determination of marker compounds . iii
Test report . iii
Packaging, storage and transportation . iii
Marking and labelling . iii
(informative) Thin-layer chromatography (TLC) identification . iii
(informative) Determination of stachydrine hydrochloride by HPLC-ELSD . iii
(informative) Determination of leonurine hydrochloride by HPLC-UV . iii
(informative) Reference information of national and regional requirements . iii
Bibliography . iii
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
iii
ISO/DISFDIS 25662:2026(en)
4 Descriptions . 2
5 Quality and safety requirements and recommendations . 5
5.1 General characteristics . 5
5.2 Morphological features . 5
5.3 Identification . 5
5.4 Moisture . 8
5.5 Total ash . 8
5.6 Acid-insoluble ash . 8
5.7 Heavy metals . 8
5.8 Pesticide residues . 8
5.9 Water-soluble extractives . 8
5.10 Marker compounds . 8
6 Sampling . 8
7 Test methods . 8
7.1 Macroscopic identification . 8
7.2 Microscopic identification . 8
7.3 Thin-layer chromatography (TLC) identification . 8
7.4 Determination of moisture content . 8
7.5 Determination of total ash content . 9
7.6 Determination of acid-insoluble ash content . 9
7.7 Determination of heavy metals . 9
7.8 Determination of pesticide residues . 9
7.9 Determination of water-soluble extractives . 9
7.10 Determination of marker compounds . 9
8 Test report . 9
9 Packaging, storage and transportation . 9
10 Marking and labelling . 10
Annex A (informative) Thin-layer chromatography (TLC) identification . 11
Annex B (informative) Determination of stachydrine hydrochloride by HPLC-ELSD . 14
Annex C (informative) Determination of leonurine hydrochloride by HPLC-UV. 17
Annex D (informative) Reference information of national and regional requirements . 19
Bibliography . 21

iv
ISO/DISFDIS 25662:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 249, Traditional medicine, Subcommittee SC 1,
Traditional Chinese medicine.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
ISO/DISFDIS 25662:2026(en)
Introduction
Leonurus japonicus herb, the dried aerial part of Leonurus japonicus Houtt., is widely used as an herbal
medicine in China and many countries. It is also known as “Yimucao” and Chinese motherwort.
In traditional Chinese medicine, this herb can activate the blood, regulate menstruation, and disperse swelling,
and is used for the treatment of irregular menstruation, dysmenorrhea, anxiety, and depression. The market,
yield, and trade volume of Leonurus japonicus herb is large, and has been developing rapidly in recent years.
[1]
Leonurus japonicus herb has been recorded in several pharmacopoeias, including Chinese Pharmacopoeia ,
[2] [3] [4]
Japanese Pharmacopoeia , Korean Pharmacopoeia , European Pharmacopoeia , and Hong Kong Chinese
[5]
Materia Medica Standards . The requirements and specifications in these standards have differences.
Therefore, it is important to develop an international standard for Leonurus japonicus herb to harmonize the
existing standards, as well as ensure the safety and effectiveness of this herb. This document benefits farmers,
consumers, enterprises and governments involved in the cultivation, regulation and trade of Leonurus
japonicus herb.
As national implementation can differ, national standards Bodies can modify the values given in 5.4 and 5.5 in
their national standards. Examples of national and regional values are given in Annex D.
vi
ISO/DISFDIS 25662:2026(en)
Traditional Chinese medicine — Leonurus japonicus herb
1 Scope
This document specifies the minimum requirements and test methods for Leonurus japonicus herb.
This document applies to Leonurus japonicus herb when traded and used internationally as natural medicine,
including both the raw 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 of 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 19609-2, Traditional Chinese medicine — Quality and safety of raw materials and finished products made
with raw materials — Part 2: Identity testing of constituents of herbal origin
ISO/TS 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 terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
Leonurus japonicus herb
dried aerial part of Leonurus japonicus Houtt.
3.2
marker compound
chemical constituent within a medicinal herb that can be used to verify its quality
Note 1 to entry: Active ingredients or chemical markers used to confirm the botanical identity of the starting material.
Note 2 to entry: There may be one or more marker compounds for a medicinal herb.
ISO/DISFDIS 25662:2026(en)
[SOURCE: ISO 22585:2022, 3.2, modified.ISO 22585:2022, 3.2, modified — Note 1 to entry has been revised.]
4 Descriptions
Figure 1 illustrates the structure of Leonurus japonicus herb, which is collected in summer when leaves and
stems are growing luxuriantly before full flowering, and then dried in the sun, either whole or after being cut
into sections.
ISO/DISFDIS 25662:2026(en)
a) flowering Flowering branch of Leonurus japonicus
...