“…Other m/z peaks in the 250–300 amu range may also record different groups of ions bearing carboxylic groups like 255.23, 283.26, and 299.25 matching C 16 H 31 O 2 + , C 18 H 35 O 2 + , and C 18 H 35 O 3 + (supporting information Figure S11), which may represent positive fragments of some middle‐chained fatty acids (e.g., linoleic, oleic, and ricinoleic acids) that have also been identified by their negatively charged fragments (see supporting information Figure S14) [ Ostrowski et al ., ; Richter et al ., ]; as well as some N‐ and P‐bearing ions such as C 5 H 13 NPO 2 + and Na 5 P 2 O 7 + [ Vaezian et al ., ] detected at 150.02 and 186.90 amu, respectively (supporting information Figure S11). Positive ions with masses greater than 300 amu include ions detected at 311.28, 313.27, 339.25, and 341.28 amu, consistent with the C 19 H 35 O 3 + , C 19 H 37 O 3 + , C 21 H 39 O 3 + , and C 21 H 41 O 3 + which can be assigned to fragments of monoacylglycerols (MAGs) bearing long‐chained fatty acids [ Leefmann et al ., ]. Other positive m/z peaks of larger ions observed at 367.43, 368.44, 369.45, 378.71, 386.65, 390.66, 394.45, 396.47, and 402.38 (supporting information Figure S11) may represent still larger hydrocarbon ions such as C 27 H 43 + , C27H44+, C 27 H 45 + , C26H50O+, C28H50+, C 27 H 46 O +, C 27 H 50 O+, C 27 H 54 O + , C 28 H 44 O + , and C 28 H 50 O + which could be ions and fragments of sterol adducts and radicals of fungi like [M‐H] + and [M]+* [ Ghumman et al ., ; Leefmann et al ., ; Nygren et al ., ; Passarelly and Winograd , ].…”