An alternative water transport system in land plants.

The evolution of vascular tissue is a key innovation enabling plants to inhabit terrestrial environments. Here, we demonstrate extra-vascular water transport in a giant, prop-rooted monocot from Lord Howe Island. Pandanus forsteri (Pandanaceae) produces gutter-like leaves that capture rainwater, which is then couriered along a network of channels to the tips of aerial roots, where it is stored by absorptive tissue. This passive mechanism of water acquisition, transport and storage is critical to the growth of aerial prop roots that cannot yet attain water via vascular conduction. This species therefore sheds light on the elaborate means by which plants have evolved to attain water.

Pandatonkinosides A and B: two new phenolic glycosides from the roots of Pandanus tonkinensis and their nitric oxide production inhibitory activities.

Two new phenolic glycosides, 4-(3-hydroxypropyl)-2,6-dimethoxyphenol ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (1), trans-cinnamyl alcohol 9-O-(6'-O-ß-D-apiofuranosyl)-ß-D-glucopyranoside (2), together with nine known phenolic glycosides (3-11) were isolated from the roots of Pandanus tonkinensis. Their structures were determined by extensive analysis of HRESIMS and NMR spectral data, as well as by comparison of their spectral data (including CD spectra) with those reported in the literature. Compounds 1-4 and 6-11 inhibited NO production in LPS-activated RAW264.7 cells with IC50 values in the range from 0.80 ± 0.06 µM to 43.38 ± 3.92 µM, whereas compound 5 was inactive. The NO production inhibitory activities of compounds 1, 4, 8, and 10 with IC50 values of 10.16 ± 1.05, 0.80 ± 0.06, 1.10 ± 0.13, and 2.79 ± 0.21 µM, respectively, are as potent as that of the positive control of NG-monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 9.80 ± 0.78 µM.

A new lignan from Pandanus tectorius.

A new lignan, named (8S, 8'S)-2,2',3,3'-tetramethoxy-4'-hydroxy-epoxylignan-4-O-ß-D-glucoside (1), together with eight known compounds (2-9), was isolated from the leaves of P. tectorius. Their structures were elucidated on the basis of spectral characteristics and comparison with the data of literatures. Besides, the absolute configuration of 1 was established by using ECD calculations. The cytotoxicity of 1 in vitro against three selected tumor cell lines (A549, HeLa and MCF-7) was evaluated by MTT assay. The results showed that compound 1 exhibited moderate cytotoxicity against HeLa cell with IC50 value of 19.30 ± 4.46 µM.

Recent Progress in the Chemistry of Pandanus Alkaloids.

The genus Pandanus (Pandanaceae) is widely distributed in the tropical and subtropical regions. With about 700 species worldwide, three Pandanus species (P. amaryllifolius, P. utilis, and P. dubius) have been investigated and found to contain new alkaloids possessing a pyrrolidinyl-α,ß-unsaturated γ-lactone, a γ-butylidene-α-methyl-α,ß-unsaturated γ-lactam, and/or indolizidine residues. Several total syntheses of Pandanus alkaloids have been accomplished. Several pharmacological studies on Pandanus species, including scientific validations of their antibacterial, antiinflammatory, antidiarrheal, and cytotoxic activities, have been conducted in relation to their traditional folk medicine uses.