Fast determination of bioactive compounds from Lycopersicon esculentum Mill. leaves

Lycopersicon esculentum leaves, usually considered as a by-product of tomato production, present several bioactive compounds of interest for industries like food, pharmaceutical and cosmetics. Nevertheless, before industrial application, suitable methods to identify and quantify those metabolites should be developed. In this study agitation with aqueous methanol was used for phenolic compounds extraction. Solid-phase extraction (SPE) was performed as the purification step before alkaloids analysis. Among the SPE sorbents tested, sulphonic acid bonded silica with H(+) counterion (SCX) proved to be the most efficient one for removing interfering components. Fifteen phenolics and four steroidic alkaloids were identified in 35 and 20 min analysis, respectively. The optimised methods were validated, revealing to be accurate, fast, simple and sensitive. Thus, these methods represent an easy and fast analytical approach, using equipment available in almost laboratory, which render them to be appropriate for routine analysis.