Xylomolins O-X: New limonoids from the Thai mangrove Xylocarpus moluccensis.

Ten new limonoids, named xylomolins O-X, were isolated from seeds of the mangrove Xylocarpus moluccensis, collected in the mangrove swamp of Trang Province, Thailand. Their structures were elucidated on the basis of comprehensive spectroscopic data analysis. The absolute configurations of five compounds (1, 3, 8-10) were unequivocally determined by single-crystal X-ray diffraction analyses, conducted with Cu Kα radiation. Xylomolins OU (1-7) are structurally intriguing mexicanolides, and xylomolin V (8) is a derivative of azadirone. Xylomolin W (9) is the first phragmalin 1,8,9-orthoester with report on X-ray crystallography from the genus Xylocarpus. In addition, xylomolin X (10) is the fifth member of the khayalactone class of limonoids with a hexahydro-2H-2,5-propanocyclopenta[b]furan motif. Compounds 1-10 inhibited NO production in LPS-activated RAW 264.7 macrophages in the range of 10.45-95.47% at the concentration of 100.0 µM. Xylomolin X (10) and xylomolin V (8), exhibited the most potent activity with IC50 values of 9.90 ± 1.84 µM and 14.66 ± 2.33 µM, respectively.

Effect of in vitro storage duration on measured mechanical properties of brain tissue.

Accurate characterization of the mechanical properties of brain tissue is essential for understanding the mechanisms of traumatic brain injuries and developing protective gears or facilities. However, how storage conditions might affect the mechanical properties of brain tissue remains unclear. The objective of this study is to investigate the effect of in vitro storage duration on the mechanical performance of brain tissue since measurements are usually carried out in vitro. Differential Scanning Calorimetry (DSC) measurements and uniaxial compression mechanical experiments are carried out. The results indicate that, for brain tissue stored at 1 °C without any liquid medium, the bio-molecular interactions and the mechanical strength of both white and grey matter deteriorate with prolonged storage duration. Transmission Electron Microscopy (TEM) results reveal the degeneration of myelin sheaths and the vacuolization of cristae with prolonged storage duration, suggesting that the in vitro storage duration should be carefully controlled. The findings from this study might facilitate the development of guidelines and standards for the in vitro storage of brain tissue.