Rubiscolin

The rubiscolins are a group of opioid peptides that are formed during digestion of the ribulose bisphosphate carboxylase/oxygenase (Rubisco) protein from spinach leaves. Rubiscolins mimic the effects of opiates and, therefore, influence the brain. These peptides have much in common with the better-known gluten exorphins.

There are 2 known rubiscolins with known structure:

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