Rosmarinic Acid Induces Proliferation Suppression of Hepatoma Cells Associated with NF-κB Signaling Pathway.

BACKGROUND: Rosmarinic acid (RA) is a natural phenolic compound that acts as a Fyn inhibitor by 53 homology modeling of the human Fyn structure. Therefore, the apoptosis mechanism related to  NF-κB signaling pathway induced by RA in HepG2 was investigated. METHODS: The cell growth, apoptosis, and proliferation of HepG2 regulated by various concentrations of RA were studied. The proteins expression of MMP-2, MMP-9, PI3K, AKT, NF-κB, and apoptosis-related proteins Bax, Bcl-2, cleaved caspase-3 were detected. RESULTS: RA significantly reduced proliferation rates, inhibited migration and invasion, and decreased the expressions of invasion-related factors, such as matrix metalloproteinase (MMP)-2 and MMP-9. TUNEL staining revealed that RA resulted in a dose-dependent increase of HepG2 cell apoptosis. In line with this finding, the expression of apoptosis suppressor protein Bcl-2 was downregulated and that of the pro-apoptotic proteins Bax and cleaved caspase-3 was increased. In addition, we found that the phosphatidylinositol 3-kinase (PI3K)/Akt/nuclear factor kappa B (NF-κB) signaling pathway was involved in RA-mediated inhibition of HepG2 cell metastasis. CONCLUSION: Our study identified that  RA as a drug candidate for the treatment of HCC.

Investigation on characteristics of 3D printing using Nostoc sphaeroides biomass.

BACKGROUND: Gel-like constructs can be produced using an extrusion-based 3D food printing (3D-FP) technique. Nostoc sphaeroides biomass is a natural gel material. Considering its good nutrition and rheological properties, these algae were chosen in this study as supply material (ink) for 3D-FP. With this gel material, the extrusion-based 3D printing system was set as a model, and the printing behavior was investigated. Furthermore, the 3D-FP mechanisms were explained through low-field nuclear magnetic resonance and rheological measurements. RESULTS: Results indicated that although fresh biomass gel was printable, non-uniformity and instability occurred during printing. Blanched inks showed non-smooth printing behavior, which was associated with a decrease in elasticity and viscosity. Printability was improved by increasing the rehydration time to 24 h when rehydrated powder was used. Increasing the rehydration time increased the water-binding degree. Pre-gelatinized potato starch was added to the mixture at ratios ranging from 1 to 100 g kg-1 . The best printing outcome was observed at 40 g kg-1 potato starch. CONCLUSION: We emphasize that elasticity and viscosity balance is an essential parameter to achieve printability. The strategies adopted in this work provide new insights into the development of personalized food regarding texture and nutritional additive content. © 2018 Society of Chemical Industry.

Effects of radio frequency and high pressure steam sterilisation on the colour and flavour of prepared Nostoc sphaeroides.

BACKGROUND: Nostoc sphaeroides has been used as a highly effective herbal medicine and dietary supplement for thousands of years. The desired dark green colour of fresh N. sphaeroides is converted into an undesirable dark brown during conventional high pressure (HP) steam sterilisation. Radio frequency (RF) sterilisation technology was used in this study to determine its effectiveness in sterilising N. sphaeroides and to achieve better preservation of natural colour and desirable flavour. Sterilisation was carried out using a 6 kW, 27 MHz RF instrument for 10, 20 and 30 min. The degree of microbial kill and the effects of RF sterilisation on colour and flavour were determined and compared with those obtained from HP steam (121 °C, 30 min) sterilisation. RESULTS: The effects of RF sterilisation on colour and flavour (measured using electronic nose) parameters were significantly lower than that in HP steam sterilisation. The RF sterilisation carried out for 20 min achieved logarithmic reduction of bacterial population and met China's national standard while preserving the colour and flavour better. CONCLUSION: Results of the present study indicated that application of RF sterilisation would improve the quality of sterilised N. sphaeroides and broaden its application in the food and health food industries. © 2017 Society of Chemical Industry.

Simulated microgravity alters growth and microcystin production in Microcystis aeruginosa (cyanophyta).

Recent researches indicated that microgravity can increase pathogenic bacteria virulence. We presumed that microgravity might affect the toxin production of toxic cyanobacteria too. Microcystis aeruginosa PCC7806 was chosen as the model organism to investigate the effects of simulated microgravity (SMG) on the growth and toxin production of toxic cyanobacteria. SMG could inhibit the growth of M. aeruginosa, which resulted in decreased cell number and lower specific growth rate after 20-day treatment. M. aeruginosa sensed the reduced gravity very quickly and immediately up-regulated its microcystin (MC) synthesis and exudation in 2 days. Subsequently, the intracellular MC content fell back since the 8(th) day and was stable around the initial level in the following days, suggesting a quick adaptation to the reduced gravity. SMG had negative effects on the photochemical system and the absorption of phosphorus in most time. However, the photosynthetic pigment concentrations and nitrogen absorption used to be transitorily stimulated upwards by SMG. It was assumed that SMG inhibited cell growth by interfering its photosynthesis and phosphorus uptake, while the enhanced MC production was related with pigment and nitrogen metabolisms. This study reveals that SMG is a novel environmental signal which inhibits growth and enhances MC production of M. aeruginosa.