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The purpose of this study is to elucidate the water dynamics in sea cucumber (Stichopus japonicas) during drying processin situby the fast and non-destructive low field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) methods.T2relaxation spectra in three-dimensional (3D) color map surface image from LF-NMR showed three main peaks assigned to bound water with relaxation time less than 2 ms, immobilized water in the range of 15–150 ms and extra-collagen fibrillar bulk water or free water adhered onto the sea cucumber with the longest relaxation time 200–1600 ms. The water dynamics in sea cucumber during drying process was clearly observed from the 3D color map surface image. Significant correlations between the LF-NMRT2parameters (ATotal, A23andT23) and TPA parameters were observed, demonstrating that LF-NMR might be a complementary technique in monitoring the textural properties of sea cucumber during drying process.

Fluorescent nanostructures (NSs) derived from polysaccharides have drawn great attention as novel fluorescent probes for potential bio-imaging applications. Herein, we reported a facile alkali-assisted hydrothermal method to fabricate polysaccharide NSs using starch and chitosan as raw materials. Transmission electron microscopy (TEM) demonstrated that the average particle sizes are 14 nm and 75 nm for starch and chitosan NSs, respectively. Fourier transform infrared (FT-IR) spectroscopy analysis showed that there are a large number of hydroxyl or amino groups on the surface of these polysaccharide-based NSs. Strong fluorescence with an excitation-dependent emission behaviour was observed under ultraviolet excitation. Interestingly, the photostability of the NSs was found to be superior to fluorescein and rhodamine B. The quantum yield of starch NSs could reach 11.12% under the excitation of 360 nm. The oxidative metal ions including Cu(II), Hg(II)and Fe(III) exhibited a quench effect on the fluorescence intensity of the prepared NSs. Both of the two kinds of the multicoloured NSs showed a maximum fluorescence intensity at pH 7, while the fluorescence intensity decreased dramatically when they were put in an either acidic or basic environment (at pH 3 or 11). The cytotoxicity study of starch NSs showed that low cell cytotoxicity and 80% viability was found after 24 h incubation, when their concentration was less than 10 mg/mL. The study also showed the possibility of using the multicoloured starch NSs for mouse melanoma cells and guppy fish imaging.

From aerial parts of the fern Pteris multifida Poir. (Polypodiaceae) two diterpenes, entkaurane- 2β,16α-diol and ent-kaur-16-ene-2β,15α-diol, were isolated by repeated column chromatography using silica gel and silica gel impregnated with silver nitrate. The structures were confirmed by spectroscopic methods. Both compounds showed a moderate cytotoxicity to Ehrlich ascites tumour cells

Turbot is a valuable commercial species because of its high nutrition content. Water redistribution during heating was attributed to temperature-induced protein denaturation and structural shrinkage. Therefore, knowledge about water dynamics provides valuable information related to flesh physical properties (weight loss, color and shear force). Herein, water dynamics in turbot during baking and microwave heating were elucidated by using low field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI). Four distinct water populations with relaxation times of 0.20–0.60 ms, 2.00–6.00 ms, 30.00–60.00 ms, and 250.00–560.00 ms were identified. The dramatic variation of water populations during baking and microwave heating indicated protein denaturation and structural shrinkage, which was further verified by MRI and microscopic examination. Furthermore, good linear correlations were observed between NMR parameters and weight loss, color and shear force. The results revealed that the water mobility and distribution in turbot provided valuable information for quality analysis during baking and microwave heating.