Phytochemistry and the systematics and ecology of Loasaceae and Gronoviaceae (Loasales)

Abstract

A screening for iridoid compounds of 78 of 315 species from all major groups in Gronoviaceae and Loasaceae has been carried out. The results were compared to the systematic concepts in the family and distribution and ecology of the taxa. Iridoids are present in at least some species of all genera screened. Some simple, monomeric compounds (e.g., loganin, sweroside) are found in all major groups of the two families and represent the basic iridoid inventory. Other compounds are restricted to certain taxonomic groups: nine-carbon iridoids (e.g., deutzioside) are restricted to Mentzelia (Loasaceae subfam. Mentzelioideae), hetero-oligomeric iridoids (e.g., tricoloroside methyl ester, acerifolioside) are restricted to two small groups in Loasa (Loasa ser. Macrospermae and ser. Floribundae, Loasaceae subfam. Loasoideae), and oleosides (e.g., 10-hydroxyoleoside dimethyl ester) are restricted to the large genus Caiophora sensu Weigend). The distribution of certain iridoid compounds thus confirms some of the generic limits. Iridoid phytochemistry does not correlate with systematic entities above the generic level nor does it in any way correlate with the morphological evolution of taxa. Conversely, the amount and complexity of iridoid compounds present in taxa correlate positively with the aridity of their habitat and the extent of mammalian herbivore pressure.

Phylogenetic relationships and generic re‐arrangements in “South Andean Loasas” (Loasaceae)

“…Iridoid phytochemistry underscores the monophyly of Caiophora (Weigend & al., 2000), while the specific composition of seed fatty acids emphasizes the coherence of Nasa (Weigend & al., 2004a). Likewise, most genus limits are also underscored by seed morphology (Weigend & al., 2004a(Weigend & al., , 2005.…”

The major clades of Loasaceae: phylogenetic analysis using the plastid matK and trnL‐trnF regions

“…7). The constrained analyses that forced the gronovioids (Cevallia, Fuertesia, Gronovia, and Petalonyx) to be the sister to the rest of the Loasaceae, modeling the segregation of Gronoviaceae from Loasaceae as advocated by Endlicher (1841) and Weigend (1997;Weigend et al, 2000), resulted in trees that were 18 state changes longer than the most parsimonious trees (Fig. 6).…”

The C-Domain of Oleuropein β-Glucosidase Assists in Protein Folding and Sequesters the Enzyme in Nucleus

“…Olea europaea (Oleaceae) produces a unique number of terpene-derived secoiridoids, known as oleosides, conjugates of glycosylated elenolic acid with a characteristic exocyclic 8,9-olefinic bond (Soler-Rivas et al, 2000). The genus Caiophora (Loasaceae) and members of the Oleaceae family are the only known source of oleosides (Weigend et al, 2000;Jensen et al, 2002;Obied et al, 2008).…”