ISO 22988:2020

INTERNATIONAL ISO
STANDARD 22988
First edition
2020-01
Traditional Chinese medicine —
Astragalus mongholicus root
Médecine traditionnelle chinoise — Racine d'astragalus
mongholicus
Reference number
ISO 22988:2020(E)
©
ISO 2020

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ISO 22988:2020(E)

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© ISO 2020
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Published in Switzerland
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ISO 22988:2020(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Descriptions . 2
5 Requirements . 3
5.1 Morphological features . 3
5.2 Moisture . 4
5.3 Total ash . 4
5.4 Water-soluble extractives . 4
5.5 Thin-layer chromatogram identification . 4
5.6 Total polysaccharides . 4
5.7 Marker compounds . 4
5.8 Heavy metals . 4
5.9 Pesticide residues . 4
5.10 Grade . 4
6 Sampling . 5
7 Test methods . 6
7.1 Macroscopic identification . 6
7.2 Determination of moisture content . 6
7.3 Determination of total ash content. 6
7.4 Determination of water-soluble extractives content . 6
7.5 Thin-layer chromatogram identification . 6
7.6 Determination of total polysaccharides content. 6
7.7 Determination of marker compound content . 6
7.8 Determination of heavy metals content . 6
7.9 Determination of pesticide residues content . 6
7.10 Root diameter . 7
7.11 Root length . 7
8 Test report . 7
9 Packaging, storage and transportation . 7
10 Marking and labelling . 7
Annex A (informative) Determination of moisture content . 8
Annex B (informative) Determination of water-soluble extractives content .9
Annex C (informative) Thin-layer chromatogram identification .10
Annex D (informative) Determination of total polysaccharides content .12
Annex E (informative) Determination of marker compound content .13
Annex F (informative) Reference information of national and regional requirements on
Astragalus root .16
Bibliography .19
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ISO 22988:2020(E)

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
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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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
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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 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.
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ISO 22988:2020(E)

Introduction
The Astragalus root (also called Astragali Radix, Milkvetch Root, Huang Qi in Mandarin, or 黄芪 or
黄耆 in Han characters) is one of the most frequently used herbal medicines in traditional Chinese
medicine (TCM).
Of roughly 80 000 TCM formulae recorded in classic TCM books, around 7,3 % contain the Astragalus
root as an ingredient. For example, of 1 493 formulae in the Chinese Pharmacopeia (2015 edition), there
are 202 which contain the Astragalus root (accounting for 13,53 %); among 148 kampo medicines for
prescription from the Ministry of Health, Labour and Welfare (MHLW) of Japan, there are 15 formulae
containing the Astragalus root (accounting for 10,14 %). In the United States, the Astragalus root is
widely sold as a dietary supplement ingredient.
Based on the statistics report for the Department of Market Supervision, Ministry of Commerce of the
People's Republic of China, the volume of Astragalus exported from China in 2015 was 4 477,2 tons,
worth 28,330,614 US$. The destination countries and regions included Malaysia, the United States,
Japan, South Korea, Australia, Thailand, Singapore, Indonesia, Vietnam, Hong Kong and Taiwan.
The Astragalus root has been used in TCM for a very long time and remains a highly valued herb today
because of its significant effects, which include:
— Efficacy supported by modern research: controls inflammation, boosts the immune system, slows
or prevents the growth of tumours, protects the cardiovascular system, regulates and prevents
diabetes and comorbidities related to diabetes, contains antioxidative and anti-ageing capabilities,
heals wounds, alleviates symptoms of chemotherapy, treats cold and flu, and provides supplemental
therapy for chronic asthma.
— Traditional indications: qi deficiency and lack of strength, reduced food intake, sloppy stool, sunken
middle qi, chronic diarrhoea, prolapse of the rectum, bloody stool, flooding and spotting, exterior
deficiency with spontaneous sweating, qi deficiency oedema, interior heat wasting-thirst, blood
deficiency and sallow complexion, hemiplegia, impediment pain, numbness, abscesses and long-
term nonhealed cellulitis caused by diabetic complications.
Two species of Astragalus, namely Astragalus mongholicus and Astragalus membranaceus, are
[1] [2]
included in the British Pharmacopoeia , the Pharmacopoeia of the People's Republic of China , the
[3] [4] [5]
European Pharmacopoeia , the Japanese Pharmacopoeia , the Korean Pharmacopoeia and the
[6]
United States Pharmacopoeia (see Table F.1). This document deals with Astragalus mongholicus;
while ISO/NP 21311 deals with Astragalus membranaceus. These two species are different in terms
of morphology and identification. Astragalus membranaceus has small numbers of large leaflets,
while Astragalus mongholicus has large numbers of small leaflets. These species can be identified and
[7] [8]
differentiated by the HPLC method and DNA barcoding . There are also many other Astragalus
species that are morphologically similar to Astragalus mongholicus, some of which are toxic. The
toxic species of Astragalus include Astragalus emoryanus var. emoryanus, Astragalus emoryanus var.
terlinguensis, Astragalus miser var. oblongifolius, Astragalus miser var. serotinus, Astragalus miser var.
hylophilus, Astragalus michauxii, Astragalus Canadensis, Astragalus oreganus, Astragalus variabilis,
Astragalus strictus, Astragalus hamiensis, Astragalus tibetanus, Astragalus confertus, Astragalus rigidulus,
and Astragalus leucoephalus, which can contain poisonous substances such as miserotoxin, karakin,
[9]
cibarin and hiptugin . Thus, the establishment of an ISO standard for Astragalus mongholicus root is
necessary to ensure the quality and safe use of this herb.
The misuse of such species in TCM remains a problem resulting in questions about the effectiveness
or unexpected side-effects of Astragalus mongholicus and Astragalus membranaceus. The establishment
of an international standard for Astragalus mongholicus root is therefore necessary to guarantee the
clinical effectiveness, safety and controllability of this valuable medicine in global commerce and trade.
Reference information on the use of Astragalus root in different countries and regions is included in
Annex F.
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ISO 22988:2020(E)

As national implementation may differ, national standards bodies are invited to modify the values
given in 5.2, 5.3 and 5.4 in their national standards. Examples of national and regional values are given
in Annex F.
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INTERNATIONAL STANDARD ISO 22988:2020(E)
Traditional Chinese medicine — Astragalus mongholicus
root
1 Scope
This document specifies the quality and safety requirements of Astragalus mongholicus root [root of
Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao].
This document applies to Astragalus mongholicus root that is sold and used as natural medicine 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 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 1575, Tea — Determination of total ash
ISO 18664, Traditional Chinese Medicine — Determination of heavy metals in herbal medicines used in
Traditional Chinese Medicine
ISO 21371, Traditional Chinese medicine — Labelling requirements of products intended for oral or topical use
1)
ISO 22217, Traditional Chinese medicine — Storage requirements for raw materials and decoction pieces
2)
ISO 22258, Traditional Chinese medicine — Determination of pesticide residues in natural products by GC
World Health Organization Quality control methods for herbal materials, General advice on sampling
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:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
Astragalus mongholicus root
dried root of Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao
Note 1 to entry: For synonyms of the Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao, see
Table F.1.
3.2
root length
distance from the bottom to the stem scar of the tap root, in centimetres
1) Under preparation. Stage at the time of publication: ISO/DIS 22217:2019.
2) Under preparation. Stage at the time of publication: ISO/DIS 22258:2019.
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ISO 22988:2020(E)

3.3
root diameter
diameter of the tap root, in centimetres
3.4
root top diameter
diameter of the tap root at the stem scar of the tap root, in centimetres
3.5
root mid-diameter
diameter of the tap root at the mid-length of the tap root, in centimetres
3.6
root bottom diameter
diameter of the tap root at the bottom of the tap root, in centimetres
3.7
marker compound
astragaloside I (C H O ), astragaloside II (C H O ), astragaloside IV (C H O ), calycosin
45 72 16 43 70 15 41 68 14
(C H O ), calycosin-7-glucoside (C H O ), formononetin (C H O ), and ononin (C H O )
16 12 5 22 22 10 16 12 4 22 22 9
3.8
batch
samples collected from the same particular place at the same time, of no more than 5 000 kg
4 Descriptions
In this document, Astragalus mongholicus root is the dried root of Astragalus membranaceus (Fisch.)
Bge. var. mongholicus (Bge.) Hsiao in the family of Leguminosae shown in Figure 1.
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ISO 22988:2020(E)

Key
A plant of Astragalus mongholicus 4 fibrous root
B dried tap root 5 tap root
C longitudinal section of the tap root 6 epidermis
D slanting section of the tap root 7 phloem
E transverse section of the tap root 8 cambium
1 flower 9 xylem
2 leaf 10 radiate striations
3 stem scar
Figure 1 — Structure of Astragalus mongholicus root
5 Requirements
5.1 Morphological features
a) The roots are cylindrical, some branched, upper part relatively thick.
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ISO 22988:2020(E)

b) The roots are 30 cm to 90 cm long, 1 cm to 3,5 cm in diameter.
c) The outer surface is pale brownish-yellow or pale brown, with irregular, longitudinal wrinkles or
furrows.
d) The texture is hard and tenacious, uneasily broken.
e) The fracture is highly fibrous and starchy, bark yellowish-white, wood pale yellow, with radiate
striations and fissures, the centre part of old root occasionally rotten wood-shaped, blackish-
brown or hollowed.
f) The odour is weak.
g) The taste is slightly sweet and slightly bean-like on chewing.
5.2 Moisture
The content of moisture in percentage mass should not be more than 10,0 %.
5.3 Total ash
The content of total ash in percentage mass should not be more than 5,0 %.
5.4 Water-soluble extractives
The content of water-soluble extractives in percentage mass should not be less than 17,0 %.
5.5 Thin-layer chromatogram identification
The thin-layer chromatogram (TLC) of Astragalus mongholicus root shall present the spots and bands
with the same colour and position corresponding to those of reference solutions.
5.6 Total polysaccharides
The content of total polysaccharides in percentage mass shall be determined.
5.7 Marker compounds
The content of marker compounds in percentage mass shall be determined.
For example, saponins (such as astragaloside I, astragaloside II or astragaloside IV) or isoflavonoids
(such as calycosin, calycosin-7-glucoside, formononetin or ononin) shall be determined according to
relevant national or regional pharmacopoeias.
5.8 Heavy metals
The content of heavy metals including arsenic, mercury, lead and cadmium shall be determined.
5.9 Pesticide residues
The content of pesticide residues shall be determined.
5.10 Grade
The grade of Astragalus mongholicus root shall be established only when all four requirements, i.e. root
top diameter, root mid-diameter, root bottom diameter and root length, are met. The root diameter and
root length of each batch of Astragalus mongholicus root shall conform to the requirements in Table 1.
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ISO 22988:2020(E)

Table 1 — Grading requirements of Astragalus mongholicus root
Root diameter
Root length
Grade
cm
cm
Root top diameter Root mid-diameter Root bottom diameter
First > 2 > 2 ≥ 0,6 > 70
Second > 1,5 > 1,5 ≥ 0,5 > 50
Third > 1 > 1 ≥ 0,4 > 40
Fourth > 0,7 > 0,7 ≥ 0,3 —
Unqualified ≤ 0,7 ≤ 0,7 < 0,3 —
NOTE 1  The requirements are based on roots collected from different production regions of Astragalus mongholicus root.
NOTE 2  The grading requirements are established according to the traditional grading system of Astragalus mongholicus
root that has long been extensively used in the market and trading and that has also been adopted by the national standards
of the People’s Republic of China.
NOTE 3  Traditionally and practically, the market price of Astragalus mongholicus root is positively correlated with the
grades. The higher the grade, the more expensive the price in the market.
NOTE 4  The grade merely reflects size and TCM knowledge of the product, which has no clear relationship with its efficacy
and safety.
6 Sampling
Sampling shall be carried out in accordance with the method described in the World Health
Organization, Quality control methods for herbal materials, General advice on sampling. Sampling of
Astragalus mongholicus root shall be conducted according to the following steps:
a) from a batch of five containers or packaging units, take a sample from each one;
b) from a batch of six units to 50 units, take a sample from five;
c) from a batch of over 50 units, sample 10 %, rounding up the number of units to the nearest multiple
of 10. For example, a batch of 51 units would be sampled as for 60, i.e. take samples from six
packages;
d) from each container or package selected, take three original samples from the top, middle and
bottom of the container or package;
e) the three original samples shall then be combined into a pooled sample which shall be mixed
carefully;
f) the average sample is obtained by quartering:
— mix the pooled sample into an even and square-shaped heap;
— divide diagonally into four equal parts;
— take two diagonally opposite parts and mix carefully;
— repeat the process as necessary until the required quantity, to within ± 10 %, is obtained.
g) using the same quartering procedure, divide the average sample into four final samples, taking
care that each portion is representative of the bulk material;
h) the final samples are tested for the measure and analyses specified in Table 2.
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ISO 22988:2020(E)

Table 2 — Maximum mass of batch and minimum mass of final sample
Minimum mass of final sample
Maximum mass per
g
batch
For measure of root mass For analysis of marker
kg
For other analyses
and root length compounds
5 000 500 250 250
NOTE 1  The establishment of the requirement is based on Astragalus mongholicus root collected from different
producing areas.
NOTE 2  Other analyses include macroscopic identification, the determinations of moisture, total ash, water-soluble
extractives, polysaccharides, heavy metals and pesticide residues, and thin-layer chromatogram identification.
7 Test methods
7.1 Macroscopic identification
Samples of not less than 250 g are taken from each batch randomly. These samples are examined by
naked eye observation, smell and taste.
7.2 Determination of moisture content
See Annex A for additional information.
7.3 Determination of total ash content
The testing method specified in ISO 1575 shall apply.
7.4 Determination of water-soluble extractives content
See Annex B for additional information.
7.5 Thin-layer chromatogram identification
See Annex C for additional information.
7.6 Determination of total polysaccharides content
See Annex D for additional information.
7.7 Determination of marker compound content
[6]
The testing method specified in Annex E, the United States Pharmacopoeia , the British
[1] [2]
Pharmacopoeia , the Pharmacopoeia of the People's Republic of China and the European
[3]
Pharmacopoeia can be used.
7.8 Determination of heavy metals content
The testing method specified in ISO 18664 shall apply.
7.9 Determination of pesticide residues content
3)
The testing method specified in ISO 22258 shall apply.
3) Under preparation. Stage at the time of publication: ISO/DIS 22258:2019.
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ISO 22988:2020(E)

7.10 Root diameter
Samples of not less than 500 g are taken from each batch randomly. The diameters of the tap root at the
stem scar, mid-length and bottom of the tap root are measured, respectively, one by one. The average
top diameter, mid-diameter and bottom diameter of the samples is then calculated, respectively.
7.11 Root length
Samples of not less than 500 g are taken from each batch randomly. The length from the bottom to the
stem scar of the tap root is measured one by one. The average length of the samples is then calculated.
8 Test report
For each test method, the test report shall specify the following:
a) all information necessary for the complete identification of the sample;
b) the sampling method used;
c) the test method used, with reference to this document, i.e. ISO 22988:2020;
d) the test result(s) obtained;
e) all operating details not specified in this document, or regarded as optional, together with details
of any incidents which may have influenced the test result(s);
f) any unusual features (anomalies) observed during the test;
g) the date of the test.
9 Packaging, storage and transportation
The packaging and transportation shall not transmit any odour or flavour to the product and shall not
contain substances which may damage the product or constitute a health risk. The packaging shall be
strong enough to withstand normal handling and transportation.
4)
The storage conditions specified in ISO 22217 shall apply.
The products shall be protected from light, moisture, pollution and entry of foreign substances during
long-distance delivery.
10 Marking and labelling
The following items shall be marked or labelled on the packages in accordance with the method
specified in ISO 21371:
a) grade of the products in accordance with 5.10;
b) all quality features indicated in Clause 5, determined in accordance with methods specified in
Clause 7;
c) gross mass and net mass of the package;
d) country of origin and province/state of the products;
e) date of production, batch number and expiry date of the products;
f) storage and transportation method.
4) Under preparation. Stage at the time of publication: ISO/DIS 22217:2019.
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ISO 22988:2020(E)

Annex A
(informative)

Determination of moisture content
A.1 Procedure
a) Weigh 250 g of sample to grind and pass it through an 80 mesh or finer sieve. Place (2–5) g of the
powdered sample in a flat weighing bottle which has been previously dried to constant mass to
form a smooth layer not exceeding 10 mm in thickness, and then weigh accurately.
b) Dry in an oven at (100–105) °C for 5 h with the stopper of the bottle removed.
c) Upon opening the oven, close the bottle promptly and allow it to cool in a desiccator for 30 min.
d) Weigh accurately and dry it again under similar conditions for 1 h, cool and weigh.
e) Repeat the operation until the difference between two successive weighings is not more than 5 mg.
A.2 Expression of result
Calculate the mass fraction of water, w (%), in the sample being examined according to the mass loss
M
on drying with Formula (A.1):
wm=−()−mm/ m ×100 (A.1)
()
Mb32 3
where
m is the mass of the flat weighing bottle (g);
b
m is the mass of the flat weighing bottle with the sample being examined before drying (g);
3
m
...