*NOTICE* - Regarding Amount Determination and Galactolipid Response
Starting on 4-29-16, KLRC is correcting our MGDG and DGDG values by dividing the the observed “signals”, which are based on comparison with the fully saturated MGDG and DGDG internal standards, by 2.8. In other words, we have determined that the average unsaturated MGDG or DGDG gives an [M + NH4]+ peak intensity that is 2.8 times the intensity of a peak from an equimolar amount of a fully saturated MGDG or DGDG peak, and we are correcting for this, so that the results can be presented in molar amounts. (Please note that we were not able to accurately determine individual response factors for various unsaturated galactolipid molecular species.) Thus, we now are including additional calculations (compared to the previous data) and the data are now presented both as signal per mg and % total signal, which represent uncorrected values for polar plant lipids (as previously presented), AND also as nmol per mg and mol%, which take into account the response factor. If you would like to correct MGDG and DGDG data acquired at KLRC as [M + NH4]+ (between ~2009 and 2016), you can divide the MGDG and DGDG values by 2.8. Generally data in signal per mg can be converted to nmol per mg this way. Phospholipid "signal per mg" data is already equivalent to "nmol per mg" (see Available Analyses page).