mRNAs for a related protein complex is found in Curculigo capitulata fruits, though at a much lower level of expression – so low that the product is undetectable by immunoblotting.
[4] Curculin is considered to be a high-intensity sweetener, with a reported relative sweetness of 430-2070 times sweeter than sucrose on a weight basis.
At a temperature of 50 °C (122 °F) the protein starts to degrade and lose its "sweet-tasting" and "taste-modifying" properties, so it is not a good candidate for use in hot or processed foods.
However, below this temperature both properties of curculin are unaffected in basic and acidic solutions,[6] so it has potential for use in fresh foods and as a table-top sweetener.
[3] In addition to challenges related to commercial production of the protein, there are many regulatory and legal issues remaining to be resolved before it can be marketed as a sweetener.