Overview
ISO 22212:2019 - Traditional Chinese medicine - Gastrodia elata tuber specifies minimum requirements and test methods for the dried, steamed or boiled tuber of Gastrodia elata Bl. (Orchidaceae) derived from cultivated and artificially propagated sources. The standard is intended for Gastrodia elata tuber used as Chinese materia medica and explicitly excludes wild forms. Its purpose is to support consistent quality, safety and identification in international trade and clinical use.
Key topics and technical requirements
- Identification and description
- Macroscopic description (shape, colour, texture, buds and scars) and defined morphological ranges (typical length 3–15 cm, width 1.5–6 cm, thickness 0.5–4 cm; tuber mass ≥ 12 g).
- Quality limits
- Moisture: mass fraction ≤ 15.0%
- Total ash: mass fraction ≤ 4.5%
- Dilute ethanol‑soluble extract: mass fraction ≥ 15.0%
- Marker compounds: identification by TLC (e.g., gastrodin, p‑hydroxybenzyl alcohol) and quantitative requirement - sum of gastrodin and p‑hydroxybenzyl alcohol ≥ 0.25%
- Contaminants and residues
- Determination of heavy metals (arsenic, mercury, lead, cadmium)
- Pesticide residues testing (examples include Benzex, DDT, quintozene)
- Sulfur dioxide content determination
- Sampling and test methods
- Sampling follows WHO guidance for herbal materials (detailed batch sampling and quartering procedures; tabled minimum sample masses)
- Test methods and references provided (e.g., ISO 1575 for total ash; ISO 5379 for sulfur dioxide; ISO 18664 for heavy metals) and informative annexes for moisture, extractives, TLC identification and quantitative assays for marker compounds.
- Packaging, storage, marking
- Requirements for packaging, storage, transportation, marking and labelling to preserve quality and support traceability.
Applications and practical value
- Ensures reproducible quality control for producers and processors of cultivated Gastrodia elata tuber.
- Supports regulators and customs in verifying identity, safety and conformity for imported/exported herbal materials.
- Guides analytical laboratories and QC departments on accepted test methods (moisture, ash, extractives, TLC, chromatographic assays, heavy metals, pesticides, SO2).
- Helps herbal product developers, manufacturers and clinical researchers ensure standardized raw material for formulation, efficacy studies and safety assessments.
- Reduces risks from adulteration and substitution, addressing species identification and toxic contaminant issues.
Related standards and references
- ISO 1575 (total ash), ISO 5379 (sulfur dioxide), ISO 18664 (heavy metals in TCM), ISO 21371 (labelling), Codex STAN 229, CAC/MRL01-2009, WHO Quality Control Methods for Herbal Materials. Informative annexes in ISO 22212:2019 cover gastrodin and p‑hydroxybenzyl alcohol identification and quantification.
Keywords: ISO 22212:2019, Gastrodia elata tuber, traditional Chinese medicine, gastrodin, p‑hydroxybenzyl alcohol, quality control, sampling, test methods, heavy metals, pesticide residues.
