@Tina Wang If you believe that your sweetener is a naturally occurring molecule, even if you have obtained it from an alternative source rather than the original natural source, please consider contributing an entry. The judging panel may, however, expect some description of the original natural source.
The Sweetness Challenge guidelines indicates that it has to be "natural." How do you define this? Does the sweetener need to be purified from its original "natural" source, or can it be purified from a recombinant source where the sequence was originally derived from the "natural" source?