However, it is important to indicate that measuring the exact mass of an unknown substance, by using of ESI–TOF–MS it can directly lead to the atomic composition and sum formula. A list of possible isobaric substances is found when searching in chemical abstracts or other databases like Scifinder, Kegg Ligand, and Massbank, among others. Additional independent information besides exact mass is necessary to base the decision on which of these isobaric is the correct match. Therefore, by combining the retention time, exact mass and the MS/MS fragmentation pattern, it will result in a generally clear identification of the unknown compounds. Information from already reported literature on the botanical family may also be used in the characterization process.