Leucine has a Natural Origin Index (NOI) of 1.00 (scale 0–1) per ISO 16128. Amino acids are fermentation or protein-hydrolysate products, natural origin. An NOI of 1.00 means 100% of its molecular mass is traceable to a natural, renewable source.

Is Leucine natural? NOI 1.00 — Is That Natural?

How we scored it

Single amino acid, produced by fermentation from plant sugars = 1.0.

What counts. ISO 16128-2 scores the atoms that remain in the final ingredient. Reagents, solvents, catalysts and protecting groups used during manufacture leave no mass behind and are not counted.

Where it comes from

Commercially produced by bacterial fermentation of plant-derived sugars such as corn or molasses. No petrochemical route is used commercially.

In plain English

An amino acid used to condition hair and skin and reduce static. Usually made by fermenting plant sugars with bacteria, the same way many food-grade amino acids are produced.

Structure

(2S)-2-amino-4-methylpentanoic acid

PubChem CID 6106 ↗

References

1ISO 16128-1:2016 and ISO 16128-2:2017 — Guidelines on technical definitions and criteria for natural and organic cosmetic ingredients and products. ISO, Geneva.
2Leucine. PubChem CID 6106. National Center for Biotechnology Information. pubchem.ncbi.nlm.nih.gov ↗
3LEUCINE. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
4LEUCINE. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=LEUCINE