Which foods contain higher levels of L-(+)-ergothioneine?

L-(+)-Ergothioneine is an amino acid derivative possessing potent antioxidant activity, obtainable from natural food sources. Mushrooms exhibit the highest L-(+)-Ergothioneine content, ranging approximately from 2.4 to 4.9 milligrams, primarily found in King oyster, maitake, oyster, and shiitake varieties. Additionally, it is present in certain soy products and grains, such as black beans, red beans, and oat bran. The antioxidant properties of L-(+)-Ergothioneine enable it to mitigate oxidative stress damage to sperm and ova, thereby enhancing fertility. Subsequent in vivo and in vitro experiments have corroborated this finding.