1H and 13C NMR assignments of new ecdysteroids from Callisia fragrans

Phytoecdysteroids: Distribution, Structural Diversity, Biosynthesis, Activity, and Crosstalk with Phytohormones

Phytoecdysteroids (PEs) are naturally occurring polyhydroxylated compounds with a structure similar to that of insect molting hormone and the plant hormone brassinosteroids. PEs have a four-ringed skeleton composed of 27, 28, 29, or 30 carbon atoms (derived from plant sterols). The carbon skeleton of ecdysteroid is known as cyclopentanoperhydrophenanthrene and has a β-sidechain on C-17. Plants produce PEs via the mevalonate pathway with the help of the precursor acetyl-CoA. PEs are found in algae, fungi, ferns, gymnosperms, and angiosperms; more than 500 different PEs are found in over 100 terrestrial plants. 20-hydroxyecdysone is the most common PE. PEs exhibit versatile biological roles in plants, invertebrates, and mammals. These compounds contribute to mitigating biotic and abiotic stresses. In plants, PEs play a potent role in enhancing tolerance against insects and nematodes via their allelochemical activity, which increases plant biological and metabolic responses. PEs promote enzymatic and non-enzymatic antioxidant defense systems, which decrease reactive oxygen species in the form of superoxide radicals and hydroxyl radicals and reduce malondialdehyde content. PEs also induce protein biosynthesis and modulate carbohydrate and lipid synthesis. In humans, PEs display biological, pharmacological, and medicinal properties, such as anti-diabetic, antioxidant, anti-microbial, hepatoprotective, hypoglycemic, anti-cancer, anti-inflammatory, antidepressant, and tissue differentiation activity.

The phytochemical, biological, and medicinal attributes of phytoecdysteroids: An updated review

The phytoecdysteroids (PEs) comprise a large group of biologically-active plant steroids, which have structures similar to those of insect-molting hormones. PEs are distributed in plants as secondary metabolites that offer protection against phytophagus (plant-eating) insects. When insects consume the plants containing these chemicals, they promptly molt and undergo metabolic destruction; the insects eventually die. Chemically, ecdysteroids are a group of polyhydroxylated ketosteroids that are structurally similar to androgens. The carbon skeleton of ecdysteroids is termed as cyclopentanoperhydro-phenanthrene with a β-side chain at carbon-17. The essential characteristics of ecdysteroids are a cis-(5β-H) junction of rings A and B, a 7-en-6-one chromophore, and a trans-(14α-OH) junction of rings C and D. Plants only synthesize PEs from mevalonic acid in the mevalonate pathway of the plant cell using acetyl-CoA as a precursor; the most common PE is 20-hydroxyecdysone. So far, over 400 PEs have been identified and reported, and a compilation of 166 PEs originating from 1998 has been previously reviewed. In the present review, we have summarized 212 new PEs reported between 1999 and 2019. We have also critically analyzed the biological, pharmacological, and medicinal properties of PEs to understand the full impact of these phytoconstituents in health and disease.

Chemical profiling and biological screening with potential anti-inflammatory activity of Callisia fragrans grown in Egypt

The ethanolic extract of Callisia fragrans aerial parts showed a significant strong in vivo anti-inflammatory and in vitro antioxidant activities with a high in vivo gastrointestinal safety profile and a very low in vitro cytotoxicity on peripheral blood mononuclear cells (PBMCs) with an IC₅₀ > 1000 μg/ml. The alcoholic extract of C. fragrans has been analysed by HPLC coupled to multiple-stage Linear Ion-Trap and Orbitrap High-Resolution mass spectrometry in negative electrospray ionisation mode (LC-ESI/LTQOrbitrap/MS/MSn). By this approach, it was possible to putatively identify 13 compounds, mainly organic acids, flavonoids, one steroid and one hydroxy-coumarin. Luteolin 6-C-glucopyranosyl-7-O-glucopyranoside, luteolin-8-C-glucopyranosyl-7-O-rhamnopyranoside, luteolin-6-C-glucoside and isoorientin 7-O-[6''-feruloyl]-glucoside were detected for the first time in C. fragrans and family Commelinaceae.

Accumulation of cadmium in potential hyperaccumulators Chlorophytum comosum and Callisia fragrans and role of organic acids under stress conditions

Cadmium (Cd) accumulation, antioxidant activity (AOA), chlorophyll fluorescence (F) and organic acid distribution in Chlorophytum comosum and Callisia fragrans plants exposed to artificially added Cd (40, 160 and 320 mg kg^-1) were examined in pot experiment. At the highest Cd concentration, C. comosum accumulated in roots and the aboveground parts up to 1331 and 1054 mg Cd kg^-1 DW, and C. fragrans up to 1427 and 1263 mg Cd kg^-1 DW, respectively, which are quite near at the level of hyperaccumulator. Cd accumulation in both plant species increased significantly with the increment of soil Cd dosage, and the distribution was roots > shoots > stolons. Values of BC showed rising trend indicating an accumulation potential of both species. The root AOA was positively correlated to Cd addition, especially in C. comosum. Higher values of free SA were found in roots with a significant enhancement at concentrations of 40 and 160 mg kg^-1 Cd. It was observed that citric acid significantly reacted in both species, while fumaric acid only in C. comosum in response to Cd which may contribute to Cd chelation. Our data indicate that both species are suitable for phytoextraction of Cd from contaminated soils which increases their value as ornamentals.