How to Choose PQQ: A 2026 Guide to Checking Salt Forms and Content Labeling of Pyrroloquinoline Quinone

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JRQ consumer verification guide　Published: November 6, 2026

Most people who ask "Which PQQ brand is good" are not missing a list of brand names. They are missing a method for checking product information. JRQ does not recommend any brand and does not compare products. This guide explains how to check PQQ products along four lines: the label, the test report, the lot number, and the storage conditions.

First question: how the PQQ amount on the label is calculated

PQQ stands for pyrroloquinoline quinone. PQQ raw materials on the market come as the free acid, as sodium and other salt forms, and as hydrates that contain water. The same amount of PQQ weighs more when it is made into a salt or a hydrate.

So a label that only says "XX mg" is not enough. You need to know whether that number is calculated as PQQ itself or as the weight of the salt or hydrate. Adequate labeling states the specific form and the basis for the amount. The test report must use the same conversion basis. The relevant standards are JRQ-Q-005 PQQ Quality Standard and JRQ-D-017 Raw Material Conversion Labeling Standard.

A stated source is needed to match the test items

The main sources of PQQ are fermentation and chemical synthesis. Different sources can leave different impurities during production, so the test items should be chosen according to the source.

First check the specification sheet or ingredient documentation to see whether the source is stated. Then ask for a test report and check whether it covers the items that match the source, such as related substances, heavy metals, and microbial tests.

If the source is unclear and the test items do not match the source, the documentation is incomplete. The chemical name, form, and source on the specification sheet should correspond one-to-one with the sample name on the test report. If the names do not match, first ask whether it is the same raw material.

Daily amount: only PQQ itself counts

The daily amount means how much PQQ is in the daily serving. When checking it, first see whether the milligram number refers to PQQ itself or to the weight of the salt or hydrate raw material.

If the label only says "PQQ disodium salt XX mg", you need to be able to find out how much that equals as PQQ itself. If you cannot find the conversion, you cannot compare different products. Different products also have different suggested numbers of tablets or capsules, so calculate the daily amount of PQQ itself before comparing. The best label is one that directly states "daily serving contains PQQ XX mg (calculated as PQQ)".

Combination products: each ingredient must be listed separately

When a product contains PQQ, NMN, and coenzyme Q10 at the same time, you cannot just look at one total weight or the words "combination formula". The label should list each ingredient separately:

• how many milligrams of PQQ calculated as PQQ itself;
• for NMN, state clearly that the amount is NMN itself, not a raw material mixture;
• for coenzyme Q10, state whether it is the oxidized form (ubiquinone) or the reduced form (ubiquinol), then give the milligrams.

The test report should measure the same form that appears on the label. The relevant standards are JRQ-Q-040 Quality Standard for Cell-Function-Related Combination Formulas and JRQ-D-018 Combination Formula Labeling Standard.

Test report and lot number: match them first, then look at results

When looking at a test report, first check whether the sample is a raw material or a finished product. The two cannot replace each other. Then check the lot number: the lot number on the report must match the bottle and the outer carton. Only when it matches does the report correspond to the batch in your hands.

The report should also state the test method, the limit of detection (LOD), or the limit of quantification (LOQ). "Not detected" only means the result is below that method's detection limit; it does not mean the content is zero. When asking the seller, you can directly request "a finished product test report for the corresponding lot number". The relevant standards are JRQ-D-005 Certificate of Analysis Disclosure Standard, JRQ-D-004 Lot Labeling Standard, and JRQ-D-016 Labeling Standard for Limits of Quantification and Detection.

Storage conditions must not be a generic line

PQQ stability can be affected by temperature, humidity, light, and air exposure after opening. The size of these effects depends on the specific formulation. The storage conditions on the label should be supported by the seller's stability data.

If the label says "consume within XX after opening", the seller should be able to provide the basis for that period. Vague storage conditions without available data are a clear warning sign. The relevant standard is JRQ-D-009 Storage Condition Labeling Standard.

Verification checklist

Common misconceptions

• Misconception: a salt form with a larger weight means higher PQQ content. Fact: the weighed number for a salt or hydrate is not the amount of PQQ itself; check the conversion.
• Misconception: a raw material report equals a finished product report. Fact: the samples are different, and one cannot replace the other.
• Misconception: "not detected" means none at all. Fact: it only means below that method's limit of detection.
• Misconception: for combination products, looking at the total milligrams is enough. Fact: check whether the label lists each ingredient separately.
• Misconception: imported products or products from a certain place are more reliable. Fact: place of origin does not replace label, test report, and lot number checks.

Related JRQ standards

• JRQ-Q-005 PQQ Quality Standard: for checking the form, calculation basis, source, and test items of PQQ.
• JRQ-Q-040 Quality Standard for Cell-Function-Related Combination Formulas: for checking labeling and testing when PQQ is combined with NMN, coenzyme Q10, or similar ingredients.
• JRQ-D-005 Certificate of Analysis Disclosure Standard: for checking that a test report corresponds to the right product, is authentic, and matches the label.
• JRQ-D-009 Storage Condition Labeling Standard: for checking the basis for the stated storage conditions.

Scope of this guide

This guide only explains how to check information. It does not evaluate any efficacy of PQQ, and it does not recommend, certify, or compare any specific product. If you are taking medication, have a chronic condition, or are pregnant or breastfeeding, consult a doctor or pharmacist before purchase.

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