Research Article
Volume 17 Issue 5 - 2022
Toxicological Evaluation of Pyrroloquinoline Quinone (PQQ) Disodium Salt Prepared by Microbial Fermentation using Methylovorus glucosotrophus
Yunji Seol1, Iris Case1, Biao Xu2, Dong Shao3, Jinlian Wu3, Jing Chen3, Wan Zhang3*
1AceOne RS, Inc., Clarksville, Maryland, USA
2WuXi AppTec (Suzhou) Co., Ltd., P.R. China
3Zhejiang Medicine Co., Ltd., Xinchang, People’s Republic of China
*Corresponding Author: Wan Zhang, Zhejiang Medicine Co., Ltd., Xinchang, P.R. China.
Received: January 20, 2022; Published: April 29, 2022


To evaluate the safety of pyrroloquinoline quinone (PQQ) disodium salt prepared by microbial fermentation using Methylovorus glucosotrophus, bacterial reverse mutation test, in vivo rat micronucleus test, and acute and subchronic oral toxicity studies in rats were conducted. Bacterial reverse mutation and in vivo rat micronucleus tests revealed that PQQ disodium salt was not mutagenic and clastogenic. The mean lethal dose (LD50) was found to be higher than 2 g/kg body weight (bw) in rats. In a 90-day oral toxicity study, Sprague-Dawley (SD) rats were fed PQQ disodium salt at daily doses of 50, 100, or 200 mg/kg bw. No treatment-related abnormalities were observed in growth, food intakes, hematology and coagulation parameters, clinical chemistry and urine analysis parameters, organ weights, and histopathological examination parameters. Thus, the no-observed-adverse-effect-level (NOAEL) was set at 200 mg/kg bw/day, the highest level tested in this study. Our data support previous studies that reported the NOAEL values ranged from 100 to 400 mg/kg bw/day for PQQ disodium salt prepared by other manufacturing methods (by chemical synthesis or by microbial fermentation using Hyphomicrobium denitrificans) and indicated that PQQ disodium salt is safe as a food ingredient.

Keywords: Pyrroloquinoline Quinone Disodium Salt; Methylovorus glucosotrophus, Bacterial Reverse Mutation Test; In Vivo Micronucleus Test in Rats; Acute Oral Toxicity; Subchronic Oral Toxicity in Rats


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Citation: Wan Zhang., et al. “Toxicological Evaluation of Pyrroloquinoline Quinone (PQQ) Disodium Salt Prepared by Microbial Fermentation using Methylovorus glucosotrophus”. EC Nutrition 17.5 (2022): 34-50.

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