ABSTRACT
Sesterterpenes are a small group of terpenoids showing a number of interesting pharmacological properties, including cytotoxicity, anti-inflammatory, anti-microbial and anti-angiogenic activities and platelet aggregation inhibition. Recently, some sesterterpene lactones isolated from Salvia dominica have been shown to modulate enzymatic activity of tubulin tyrosine ligase (TTL), a promising target for new anticancer therapeutic strategies. However, to allow a direct use of S. dominica extracts as a source of TTL inhibitors, analytical method aimed to their fast qualitative and quantitative characterization is required. Despite the structural features and diverse biological activities of sesterterpenoids, actually no analytical method for their quantization into complex mixtures has been published. Here we describe an LC-MS/MS method aimed to qualitative and quantitative analysis of sesterterpenes lactones in the crude extracts obtained from different parts of S. dominica. This approach allowed us to characterize all the sesterterpenes by a single step analysis and also to identify two unknown compounds. Moreover, a quantitative comparison of the composition in sesterterpenes of extracts obtained from S. dominica leaves, roots and leaf galls was performed, leading to the definition of both leaves and leaf galls as suitable sources of TTL inhibitors.
Subject(s)
Chromatography, Liquid/methods , Salvia/chemistry , Sesterterpenes/analysis , Enzyme Inhibitors/analysis , Enzyme Inhibitors/isolation & purification , Peptide Synthases/antagonists & inhibitors , Plant Extracts/analysis , Plant Extracts/chemistry , Plant Leaves , Plant Roots , Sesterterpenes/isolation & purification , Tandem Mass Spectrometry/methodsABSTRACT
One new flavonoid glycoside, 3-O-kaempferol 4-O-(galloyl)-beta-D-glucoside, one new bergenin derivative, 11-0-caffeoylbergenin, along with other known flavonoids and phenolic derivatives, were isolated from the leaves of Securinega virosa. Their structures were established on the basis of detailed spectral analysis. In vitro biological analysis of the isolated compounds showed that they were able to quench DPPH radicals and had a direct scavenging activity on superoxide anion. Kaempferol 3-O-(4-galloyl)-beta-D-glucopyranoside (1), 11-0-caffeoylbergenin (2), and glucogallin (6) exhibited the highest antioxidant capacity, being also able to modulate hydroxyl radical formation more efficiently than the other compounds, acting as direct hydroxyl radical scavengers and chelating iron.
