Quantitative Determination of Andrographolide and Related Compounds in Andrographis paniculata Extracts and Biological Evaluation of Their Anti-Inflammatory Activity.

Extraction, isolation and characterization of Andrographis paniculata (A.p.) products were developed. Three natural diterpenes compounds were obtained and one was used for chemical modifications. Evaluation of their inhibition of TNFα induced NFκB transcriptional activity. A rapid analytical method for the determination and quantitation of three diterpenoid lactones (andrographolide 1, didehydroandrographolide 2, neoandrographiside 3) found in A. paniculata extracts was investigated. After some optimizations on column type and injection solvent, the separation was achieved in 9 min on a monolithic Chromolith Performance RP18e column (100 mm × 4.6 mm ID, 2 µm), with a gradient solvent system of water and methanol, UV detection at 220 nm and ELSD detection. The method was proved to be suitable for the quantitation of these three diterpenes in four different commercial Andrographis dietary supplements. The anti-inflammatory activities of a mixture of known composition have been evaluated showing differences in activity depending on the relative ratio of various diterpenes and also a possible synergic activity for some of them.

Simplified strigolactams as potent analogues of strigolactones for the seed germination induction of Orobanche cumana Wallr.

BACKGROUND: Strigolactones play an important role in the rhizosphere as signalling molecules stimulating the seed germination of parasitic weed seeds and hyphal branching of arbuscular micorrhiza, and also act as hormones in plant roots and shoots. Strigolactone derivatives, e.g. strigolactams, could be used as suicidal germination inducers in the absence of a host crop for the decontamination of land infested with parasitic weed seeds. RESULTS: We report the stereoselective synthesis of novel strigolactams, together with some of their critical physicochemical properties, such as water solubility, hydrolytic stability, as well as their short soil persistence. In addition, we show that such strigolactams are potent germination stimulants of O. cumana parasitic weed seeds and do not affect the seed germination and the root growth of sunflower. CONCLUSIONS: The novel strigolactam derivatives described here compare favourably with the corresponding GR-28 strigolactones in terms of biological activity and physicochemical properties. However, we believe strigolactone and strigolactam derivatives require further structural optimisation to improve their soil persistence to demonstrate a potential for agronomical applications. © 2016 Society of Chemical Industry.

Chemicals inducing seed germination and early seedling development.

Seed germination and early seedling development are essential events in the plant life cycle that are controlled largely by the interplay and cross-talk between several plant hormones. Recently, major progress has been achieved in the elucidation at the molecular level of the signalling of these phytohormones. In this review, we summarise the data for the most promising classes of compounds, which could find potential agronomic applications for promoting seed germination and early seedling development even under abiotic stress conditions. Structural modifications of plant hormones are required to improve their biological performance and their specificity to allow commercial application.