Shen Qu
StarN/A (fermented preparation of flour, Polygonum hydropiper, Artemisia annua, Prunus armeniaca, Vigna angularis, Xanthium sibiricum)
Traditionally used for
- Digestion
Cautions & contraindications
- Pregnancy
- Breastfeeding
- Young children
- Liver conditions
- Diabetes
☯ TCM Properties
Promotes Digestion and Resolves Food Stagnation; Harmonizes the Stomach; Strengthens the Spleen; Regulates Qi and Harmonizes the Middle Burner; Releases the Exterior
Traditional Chinese Uses
Shen Qu (medicated leaven) is a fermented preparation of several herbal ingredients combined with wheat or rice bran. It reduces food stagnation from undigested grains and starchy foods, improves appetite, and harmonizes the Stomach. It is especially useful after overeating or in cases of Spleen-Stomach weakness with chronic digestive sluggishness. As a prepared fermented substance, it assists the digestive process with a gentle, food-compatible action.
Relationships
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Botanical Description
Shen Qu, known in English as medicated leaven or massa medicata fermentata, is not a single botanical species but a compound preparation in the Chinese materia medica produced by mixing wheat flour and wheat bran with the fresh herbs Artemisia annua (Qing Hao), Polygonum hydropiper (Liao), Xanthium sibiricum (Cang Er), and the juices of bitter almond and red bean. The dampened mixture is packed into blocks or cakes and allowed to ferment under controlled humidity until colonized by molds, yeasts, and bacteria, producing a fragrant yellow-brown mass. The cakes are then sun-dried, broken into pieces, and often further dry-roasted before dispensing. As a fermented preparation, the resulting drug contains digestive enzymes, organic acids, and microbial metabolites, and is classified within the category of food-stagnation resolving agents in traditional Chinese medicine.
Active Constituents
alpha-Amylase
Glycoside hydrolase enzyme (microbial fermentation product)Concentration: Activity peaks at day 4 of a 9-day fermentation (Xu et al. 2013); higher in leaven made with Aspergillus oryzae than with Rhizopus oryzae
The enzyme most directly responsible for the traditional indication of food stagnation, hydrolysing dietary starch. It is generated by the fermenting organisms rather than present in the raw flour and herbs, so a poorly fermented or over-dried batch carries little of it. Amylase activity is the usual laboratory proxy for potency of this drug.
Protease
Peptide hydrolase enzyme (microbial fermentation product)Concentration: Rises continuously to the end of the 9-day fermentation (Xu et al. 2013); marginally higher with Rhizopus oryzae than Aspergillus oryzae
Hydrolyses dietary protein and, unlike amylase, keeps accumulating throughout fermentation, so protease activity tracks fermentation duration. Together with amylase and lipase it accounts for the digestive action attributed to the drug.
Lipase
Carboxylesterase enzyme (microbial fermentation product)Concentration: Activity peaks at day 4 of fermentation; higher in Aspergillus oryzae leaven than Rhizopus oryzae leaven
Hydrolyses dietary triglycerides, completing the trio of digestive enzymes measured as quality indicators for this drug. Its presence is one reason the classical indication is stagnation from fatty and rich food rather than from starch alone.
Carboxymethyl cellulase
Glycoside hydrolase enzyme (microbial fermentation product)Concentration: Activity peaks at day 4 of fermentation (Xu et al. 2013)
A cellulolytic activity generated during fermentation that helps break down the bran and plant cell wall material in the leaven itself, and is used alongside amylase as a fermentation-progress marker.
Ferulic acid
Hydroxycinnamic acid (phenolic acid)Concentration: Consistently present across 13 commercial products; significantly higher in Chinese-made than Korean-made leaven (Wang et al. 2020)
Released from the bound form in wheat bran by microbial feruloyl esterases during fermentation, and one of the few small molecules present in every commercial product analysed. It carries antioxidant and anti-inflammatory activity and has been proposed as a chemical reference marker for a drug that currently has none.
Lactic acid
Organic acid (fermentation metabolite)Concentration: Commonly found across commercial products alongside citric and acetic acid
A product of the bacterial phase of fermentation which acidifies the leaven, contributes to its keeping quality and is part of the organic acid profile common to all commercial products.
Acetic acid
Organic acid (fermentation metabolite)Concentration: Commonly found across commercial products
A fermentation acid contributing to the sour character and low pH of the finished cake. Like lactic acid it is a marker that fermentation actually occurred rather than a therapeutic constituent in its own right.
Citric acid
Organic acid (fermentation metabolite)Concentration: Commonly found across commercial products
An organic acid detected consistently in commercial leaven, of interest mainly as one of the quality-control commonalities identified across otherwise highly variable products.
Acetoin
Alpha-hydroxy ketone (fermentation volatile)Concentration: Detected in fermented leaven only, absent from the unfermented raw mixture
Together with 2,3-butanediol and guaiacol it appears only after fermentation, so its presence distinguishes genuine leaven from a simply dried mixture of the raw ingredients. It is a marker of authenticity rather than a pharmacologically active component.
2,3-Butanediol
Diol (fermentation volatile)Concentration: Detected in fermented leaven only, absent from the unfermented raw mixture
A microbial fermentation volatile absent from the raw ingredients, used with acetoin and guaiacol as evidence that fermentation has taken place. Meanwhile terpenoids from the fresh herbs decrease as fermentation proceeds.
Amygdalin
Cyanogenic diglucosideConcentration: Present in the raw apricot kernel component; progressively degraded during fermentation (Xu et al. 2019)
Contributed by the Prunus armeniaca kernel in the recipe and the one intrinsically hazardous plant constituent of the mixture, since hydrolysis releases hydrogen cyanide. Fermentation degrades amygdalin along with benzaldehyde and rutin, so a properly fermented leaven carries far less than the raw ingredients; an under-fermented product carries more.
Aflatoxin B1
Difuranocoumarin mycotoxin (contaminant, not an intended constituent)Concentration: Variable and product-dependent; Chinese Pharmacopoeia limits for medicinal materials are 5 micrograms/kg for aflatoxin B1 and 10 micrograms/kg for the sum of B1, B2, G1 and G2
Not a constituent of the drug as designed, but the predictable hazard of an open, non-sterile solid-state fermentation of grain. Aspergillus is the dominant genus recovered from commercial leaven, and the intended production organism Aspergillus oryzae is a non-aflatoxigenic domesticated form of the aflatoxin-producing Aspergillus flavus, from which it is not easily distinguished by eye. Aflatoxin B1 is a Group 1 human carcinogen and a hepatotoxin.
⚠ Drug Interactions
Hepatotoxic drugs (paracetamol, methotrexate, isoniazid) and antiviral therapy for chronic hepatitis B
This drug is a grain fermented in the open air, and Aspergillus is the genus most consistently recovered from commercial products. Because the intended organism, Aspergillus oryzae, is a domesticated non-toxigenic form of the aflatoxin-producing Aspergillus flavus, an uncontrolled fermentation can favour the toxigenic relative without any visible difference. Aflatoxin B1 is a hepatotoxin and Group 1 carcinogen whose hepatocellular carcinoma risk is strongly multiplicative with chronic hepatitis B infection. Commercial products are known to differ greatly in their microbiology and there is no mandatory aflatoxin assay specific to this drug, so absence of a reported result is not evidence of a clean batch.
Clinical note: Prefer products from a manufacturer that uses a defined starter culture and can supply mycotoxin test results. Avoid prolonged courses in patients with chronic hepatitis B or C, cirrhosis, or on other hepatotoxins, and do not use a batch that is visibly mouldy, discoloured or musty.
Corticosteroids, cytotoxic chemotherapy and other immunosuppressants
The drug is deliberately grown on Aspergillus species and Rhizopus oryzae and is dried rather than sterilised, so viable spores and hyphal fragments of both genera can persist in the finished cake. These are precisely the organisms responsible for invasive aspergillosis and mucormycosis in neutropenic and transplant patients, and Rhizopus oryzae is the commonest agent of mucormycosis. No case of invasive infection attributed to this drug has been published, so the concern rests on the microbiology of the preparation rather than on reported cases.
Clinical note: Do not give to neutropenic, transplant or otherwise significantly immunosuppressed patients, and avoid it in poorly controlled diabetes and iron overload, which are the classic risk states for mucormycosis. Choose a non-fermented digestive herb such as Mai Ya or Shan Zha instead.
Monoamine oxidase inhibitors (phenelzine, tranylcypromine, linezolid)
Prolonged protein-rich fermentation with a continuously rising protease activity is the standard route by which tyramine accumulates in fermented foods, and tyramine is the substrate whose accumulation causes hypertensive crisis when monoamine oxidase is inhibited. Amino acids and their derivatives are among the metabolite classes that rise during fermentation of this drug, but tyramine itself has not been quantified in it, so this remains an inference from the fermentation chemistry rather than a measured finding.
Clinical note: Avoid or use only with blood pressure monitoring in patients on an irreversible MAO inhibitor or on linezolid. The risk with a few grams of leaven is far smaller than with aged cheese or soy sauce, but the drug offers no benefit that justifies the uncertainty.
Cang Er Zi (Fructus Xanthii) prescribed in the same formula
Xanthium sibiricum is one of the herbs in the classical six-ingredient leaven recipe, and Xanthium tissue carries the kaurene diterpene glycosides atractyloside and carboxyatractyloside, which inhibit the mitochondrial adenine nucleotide translocase and cause hepatocellular necrosis. The Xanthium fraction of the leaven is small and no atractyloside assay of finished leaven has been published, so the additional exposure is likely to be minor. The point is that a patient given both drugs is not receiving Xanthium from only one source, and recipes vary between manufacturers.
Clinical note: When prescribing Cang Er Zi and Shen Qu together, keep the Cang Er Zi at pharmacopoeial dose and the course short, and monitor liver function if treatment continues beyond a few weeks. Ask the supplier whether their leaven recipe includes Xanthium, as some modern formulations omit it.
Ku Xing Ren (bitter apricot kernel, Semen Armeniacae Amarum) prescribed in the same formula
Apricot kernel is a recipe ingredient of the leaven, so a formula containing both drugs delivers amygdalin from two sources. Fermentation degrades amygdalin along with benzaldehyde and rutin, which limits the contribution from the leaven, and an under-fermented product would contribute more. The clinically meaningful cyanogenic load in such a formula comes from the separately prescribed kernel, not from the leaven.
Clinical note: Keep bitter apricot kernel within its pharmacopoeial dose, which is the dose-limiting component; no separate adjustment for the leaven is warranted. Be more cautious with an obviously under-fermented or unfermented product.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 6–15 g | Daily | — | — | Standard oral dose per Xi S, Gong Y. Essentials of Chinese Materia Medica and Medical Formulas. Academic Press/Elsevier, 2017, pp. 189–192. Exact wording: Normally, 6–15 g is decocted with water as an oral |
Dui Yao — Herb Pairs
The classical two-herb combinations this herb appears in, each with an action neither herb has alone.
Reduce food stagnation of different kinds together, the one especially for meat and fat, the other for grain and alcohol.
Food stagnation with epigastric fullness, belching and acid regurgitation.
Core pair of a classical formula — Bao He Wan, Dan Xi Xin Fa (Zhu Danxi)
Evidence Tier
Moderate evidence · 6 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
0
In vitro / animal
4
1 verified · 3 unverified
Show 4 studies
- Effects of microbial fermentation on enzyme activity and volatile properties of Massa Medicata Fermentata
- The components and amylase activity of Massa Medicata Fermentata during the process of fermentation
- Comprehensive analysis on the regulatory mechanism of active ingredient accumulation during fermentation process of Massa Medicata Fermentata: microbe and metabolic profiles
- Massa Medicata Fermentata treated spleen deficiency constipation by mediating intestinal microbiota and serum peptide
Other / unclassified
2
0 verified · 2 unverified
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Microbial Community Structure and Chemical Constituents in Shinkiku, a Fermented Crude Drug Used in Kampo Medicine
Thirteen commercial leaven products made in China and Korea were profiled by amplicon sequencing and chemical analysis. Aspergillus was the microorganism common to all products, and every product contained the digestive enzymes alpha-amylase, protease and lipase, the organic acids ferulic, citric, lactic and acetic acid, and 39 shared volatile compounds. Beyond those commonalities the microbiology and chemistry differed markedly by manufacturer: Aspergillus predominated in Korean products, which had higher enzyme activities, while Bacillus was typical of Chinese products, which had more ferulic acid, benzaldehyde and anethole. The authors state plainly that there are no reference standards for the quality of medicinal leaven and argue that microbial management is essential to stabilise it.
Monitoring of the bacterial and fungal biodiversity and dynamics during Massa Medicata Fermentata fermentation
Culture-dependent plating and PCR-DGGE tracked the organisms through a 9-day fermentation. It runs in two phases: a bacterial pre-fermentation from day 0 to 4, peaking at 1.2 times 10 to the 10th CFU/g at day 2, and a fungal post-fermentation from day 5 to 9, reaching 6.3 times 10 to the 5th CFU/g at day 9. The 170 isolates fell into the genera Enterobacter, Klebsiella, Acinetobacter, Pseudomonas, Mucor, Saccharomyces, Rhodotorula and Amylomyces, with Enterobacter, Pediococcus, Pseudomonas, Mucor and Saccharomyces dominant. Amylase, carboxymethyl cellulase and lipase peaked at day 4 while protease rose to the end. Note that the recovered flora includes Klebsiella, Acinetobacter and Pseudomonas, which is what an uncontrolled open fermentation of grain yields.
Effects of microbial fermentation on enzyme activity and volatile properties of Massa Medicata Fermentata
Raw materials were mixed to the National Standard for Chinese Patent Drugs ratio and fermented with pure cultures of either Aspergillus oryzae or Rhizopus oryzae. Fermentation raised enzyme activity overall; the Aspergillus oryzae product had higher alpha-amylase and lipase activity, the Rhizopus oryzae product marginally higher protease. Terpenoids from the fresh herbs fell with fermentation while 2,3-butanediol, acetoin and guaiacol appeared only in the fermented material. The authors conclude that commercial quality varies greatly and that microbial control of production is essential, which is the practical basis for preferring defined-starter products.
The components and amylase activity of Massa Medicata Fermentata during the process of fermentation
Chemical composition and amylase activity were followed through fermentation. Amygdalin, benzaldehyde and rutin were progressively degraded, and the HPLC fingerprint of 7-day fermented leaven had a similarity of only 0.106 to the unfermented mixture, meaning fermentation produces a chemically different drug rather than a flavoured version of the raw ingredients. Amylase activity rose steadily. PCR-SSCP classified 23 fungal species, dominated by Eurotiomycetes at 48 percent, the class that contains Aspergillus and Penicillium.
Comprehensive analysis on the regulatory mechanism of active ingredient accumulation during fermentation process of Massa Medicata Fermentata: microbe and metabolic profiles
Physicochemical, microbiome and broad-target metabolomic profiling at 0, 48, 72 and 96 hours showed bacterial diversity rising and fungal diversity falling through fermentation. Differential metabolites were mainly lipids, amino acids and derivatives, phenolic acids, organic acids, flavonoids, lignans and coumarins, nucleotides and alkaloids, and most peaked at 72 hours. Structural equation modelling linked Bacillus velezensis and Bacillus safensis and the fungi Apiotrichum montevideense, Geotrichum bryndzae, Saccharomycopsis fibuligera and an unidentified Dipodascaceae to those metabolites. This gives a defensible endpoint for fermentation duration, which classical practice judged by feel.
Massa Medicata Fermentata treated spleen deficiency constipation by mediating intestinal microbiota and serum peptide
Eighteen male Kunming mice were assigned to normal, spleen-deficiency-constipation model and treatment groups, the last receiving 4 g/kg/day of aqueous leaven infusion for 7 days. The model reduced faecal water content, lowered serum substance P and raised vasoactive intestinal peptide and calcitonin gene-related peptide. Treatment moved all three peptides and restored intestinal microbial diversity, with Ligilactobacillus positively correlated with substance P and negatively with vasoactive intestinal peptide. The sample is small (n = 6 per group) and the model is a TCM-pattern construct rather than a defined human disease, so this supports a prokinetic mechanism rather than clinical efficacy.
⚠ Safety & Contraindications
- Pregnancy
- Breastfeeding
- Young children
- Liver conditions
- Diabetes
Contraindications
Its use is prohibited in women in lactation for infant, patients with spleen yin deficiency, intense stomach fire and no food accumulation, and cautious in pregnant women.
Source: Xi S, Gong Y. Essentials of Chinese Materia Medica and Medical Formulas. Academic Press/Elsevier, 2017, pp. 189–192.
Historical Texts
Qi Min Yao Shu (Essential Techniques for the Welfare of the People), Jia Sixie
Northern Wei dynasty, c. 544 CEYao Xing Lun (Treatise on Medicinal Properties), Zhen Quan
Tang dynasty, c. 620 CEBen Cao Gang Mu (Compendium of Materia Medica), Li Shizhen
Ming dynasty, 1578Dan Xi Xin Fa (Teachings of Zhu Dan-Xi)
Yuan to early Ming, compiled 1481References
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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