This product is sourced from Aspergillus flavus by microbial fermentation.
A sample certificate of origin is available at this link: https://www.sigmaaldrich.com/US/en/coo/undefined/A6636/*
The item is not an analytical standard.
Please see the link below to review product 34029, which has been tested for use as an analytical standard:
https://www.sigmaaldrich.com/US/en/product/sial/34029.