downwardsfromzero
Boundary condition
murklan - I'm wondering about the chemistry of your well water. There may be an insoluble double salt of harmalla alkaloids and something like magnesium from your water that only forms at lower temperatures, but once formed it resolutely refuses to redissolve.
I also suspect the seeds of possibly containing oxalates and/or other organic anions which will form an insoluble precipitate with calcium or magnesium - maybe phytates? Perhaps this precipitate will adsorb some of the alkaloids leading to the observed fluorescence. The amounts of available phytate/oxalate were perhaps increased by your more thorough grinding this time.
Phytates seem like a reasonable candidate here because they're comprised of a phosphate substituted polyol. Magnesium ammonium phosphate is very poorly soluble in water so perhaps magnesium harm(al)inium phytate is similarly insoluble?
That's the two ideas that have sprung to mind so far, and it's worth noting they're not mutually exclusive, they could compound each other.
I also suspect the seeds of possibly containing oxalates and/or other organic anions which will form an insoluble precipitate with calcium or magnesium - maybe phytates? Perhaps this precipitate will adsorb some of the alkaloids leading to the observed fluorescence. The amounts of available phytate/oxalate were perhaps increased by your more thorough grinding this time.
Phytates seem like a reasonable candidate here because they're comprised of a phosphate substituted polyol. Magnesium ammonium phosphate is very poorly soluble in water so perhaps magnesium harm(al)inium phytate is similarly insoluble?
That's the two ideas that have sprung to mind so far, and it's worth noting they're not mutually exclusive, they could compound each other.