The food additive fumonisin esterase may be safely used to degrade fumonisins in swine and poultry feed in accordance with the following prescribed conditions:

(a) Fumonisin esterase, a carboxylesterase, is produced by a nontoxigenic and nonpathogenic yeast, Komagataella phaffii, genetically engineered to express the fumonisin esterase gene from the bacterium Sphingopyxis sp. Hydrolyzed fumonisin and two tricarballylic acid molecules are the reaction products of fumonisin hydrolysis by this 493 amino acid fumonisin esterase enzyme.

(b) The additive shall meet the following specifications:

(1) The fermentation media for the Komagataella phaffii shall not contain methanol.

(2) Viable genetically engineered Komagataella phaffii shall not be present.

(3) One unit of fumonisin esterase activity is defined as the amount of enzymatic activity required to release one micromole of tricarballylic acid (CAS 99-14-9) per minute from 100 micromolar fumonisin B1 in 20 millimolar Tris-hydrochloride buffer (pH 8.0) containing 0.1 milligram per milliliter of bovine serum albumin at 30 °C.

(c) The additive is incorporated at a minimum of 15 units of fumonisin esterase activity per kilogram of complete feed:

(1) Complete swine feeds cannot contain more than 10 parts per million of total fumonisins.

(2) Complete feed for poultry being raised for slaughter cannot contain more than 50 parts per million of total fumonisins.

(3) Complete feed for breeding poultry and hens laying eggs for human consumption cannot contain more than 15 parts per million of total fumonisins.

(d) To assure safe use of the additive, in addition to the other information required by the Federal Food, Drug, and Cosmetic Act:

(1) The label and labeling of the additive, any feed premix, and complete feed shall contain the common or usual name of the additive's source, dried Komagataella phaffii fermentation product.

(2) The label and labeling of the additive and any feed premix shall also contain:

(i) Adequate directions for use including a statement that the additive must be uniformly applied and thoroughly mixed into complete feeds;

(ii) A guarantee for the minimum amount of fumonisin esterase activity, expressed in accordance with paragraph (b)(3) of this section, and the unit of weight being consistent with the inclusion rate stated in the directions for use;

(iii) Appropriate warning and safety precaution statements concerning the additive as a respiratory sensitizer;

(iv) A cautionary statement concerning the maximum fumonisin content as established in paragraph (c) of this section.

[87 FR 47344, Aug. 3, 2022, as amended at 87 FR 52682, Aug. 29, 2022]