High‐performance liquid chromatography‐diode array detection‐electrospray ionization multi‐stage mass spectrometric screening of an insect/plant system: the case of Spodoptera littoralis/Lycopersicon esculentum phenolics and alkaloids

Abstract

High-performance liquid chromatography-diode array detection-electrospray ionization multi-stage mass spectrometry (HPLC-DAD-ESI-MS(n)) is considered to be a very valuable tool for the characterization of compounds found in trace amounts in natural matrices, as their previous isolation and clean-up steps can be avoided. Micro-scale separation increases the potential of this analytical technique, allowing the determination of compounds in reduced samples. Spodoptera littoralis represents a major challenge to Solanaceae plants, as it is one of the most deleterious pests. The S. littoralis/Lycopersicon esculentum system was studied for the first time concerning glycoalkaloids and phenolics. Using HPLC-DAD-ESI-MS(n) we were able to characterize 15 phenolic compounds in L. esculentum leaves. Nine of them are reported for the first time. Some differences were found between leaves of cerasiforme and 'Bull's heart' varieties. However, in the materials of S. littoralis (larvae, adults, exuviae and excrements) reared in both L. esculentum leaves no phenolics were identified. α-Tomatine was the main glycoalkaloid in the host plant. The glycoalkaloid composition of the different S. littoralis materials was distinct, with α-tomatine and dehydrotomatine being the main detected compounds in larvae and excrements. These results add knowledge to the ecological interaction in this insect/plant duo, for which it is hard to obtain considerable sample amounts.

Fast determination of bioactive compounds from Lycopersicon esculentum Mill. leaves

“…Spectral data from all peaks were accumulated in the range of 200-400 nm, and chromatograms were recorded at 205 nm. The different steroidic alkaloids were identified by comparison with authentic standards and with published data (Ferreres et al, 2011). Steroidic alkaloids quantification was achieved by the absorbance recorded in the chromatograms relative to external standards.…”

“…Phenolic compounds were extracted using a mixture of methanol/water (1:1), which allows the recovery of a wide range of polyphenols with diverse structures (Ferreres et al, 2011;Abad-García et al, 2007;Taveira et al, 2009).…”

“…(Solanaceae) is a widely studied species, but only few works focus their attention on its leaves. Although this plant material is considered a by-product of tomato production, it contains several bioactive metabolites, such as steroidic alkaloids (Friedman, 2002) and phenolics, namely hydroxycinnamic acids and flavonoids (Ferreres et al, 2011;Slimestad & Verheulb, 2009). These compounds are known to be involved in both host-plant defences and to have several pharmacological and nutritional functions in humans (Friedman, 2002).…”

Chemical Constitutions and Antioxidant Activities of Tomato Leaf Extracts

“…However, only a few research studies have focused on tomato leaves (Taveira et al 2012). Although this plant material is considered a by-product of tomato production, it contains several bioactive metabolites, including steroidic alkaloids (Friedman 2002) and phenolics such as hydroxycinnamic acids and flavonoids (Slimestad and Verheul 2009;Ferreres et al 2011). These compounds are known to be involved in host-plant defenses.…”

Landscape effects on the abundance and larval diet of the polyphagous pest Helicoverpa armigera in cotton fields in North Benin

“…The proportion of tomato plants in the landscape may explain a significant proportion of individuals having fed on C 3 plants, because tomato plants, like cotton, have a C 3 photosynthetic pathway 64 Further studies should focus on tomato plants as larval host plants with the development of a marker, but the biochemical tomato marker tomatine has been difficult to implement. 65 Resistance to insecticides used for tomato crops should also be investigated. 42 …”