Chromatography Forum

Hello all, I am doing research on profiling bioactive compounds of a mushroom. I have identified about 34 compounds, most have been been previously identified in mushrooms before but one compound silymarin which has never been identifed before in mushroom and has only been identifed in milk thistle plant previously. silyamrin itself is a complex flavonolignan complex of several compounds. so to absolutley identify this i would have to purify the compound from the sample which consists of a very small portion of the main fraction (0.64%).then separate out further this complex mixture......this is another years work in itself to do. so my question is can i report on my publication silymarin....along with the other compounds with just a mass spectra libary match??

There is little to no chance that an identification based only on an MS library match will make it past the referees, more especially since its occurrence in mushrooms is a new finding (there would be less problem if you found it in a close relative of the milk thistle for example). I expect that the minimum that you would need is a co-elution with an authentic standard, and presuming that this is LC-MS which has low resolution separations, two sets of separation conditions would be a lot more convincing than one. You could also try MS-MS to show that secondary fragmentations are the same between your molecule and the standard.

Peter

hey peter...thanks for your reply. i have seen many papers with published data based soley on MS for compounds previously identified in mushrooms but are you saying it would be near impossible to publish my data identifying for the first time a compound not identified in fungi before? well i guess its not a big deal i can just exclude it....but it makes me think my professors dont have a clue! and they never warned me

Different journals have different standards. There is a big difference between reporting that a compound whose presence is no surprise at all is actually present, and reporting that a compound whose presence is a big, intersting and potentially important surprise is present. You need more convincing evidence in the latter case. What evidence do you have that the compound is silymarin, and not something else ? What kind of MS data do you have ? - if it is just a MW from a simple LC-ESI-MS run, than ask yourself the question how many other molecules have the same MW ? If you have MS-MS, or APCI fragmentation, how selective and distinctive are the fragmentations ?

Peter