The rice LATE ELONGATED HYPOCOTYL enhances salt tolerance by regulating Na+/K+ homeostasis and ABA signalling.

The circadian clock plays multiple functions in the regulation of plant growth, development and response to various abiotic stress. Here, we showed that the core oscillator component late elongated hypocotyl (LHY) was involved in rice response to salt stress. The mutations of OsLHY gene led to reduced salt tolerance in rice. Transcriptomic analyses revealed that the OsLHY gene regulates the expression of genes related to ion homeostasis and the abscisic acid (ABA) signalling pathway, including genes encoded High-affinity K+ transporters (OsHKTs) and the stress-activated protein kinases (OsSAPKs). We demonstrated that OsLHY directly binds the promoters of OsHKT1;1, OsHKT1;4 and OsSAPK9 to regulate their expression. Moreover, the ossapk9 mutants exhibited salt tolerance under salt stress. Taken together, our findings revealed that OsLHY integrates ion homeostasis and the ABA pathway to regulate salt tolerance in rice, providing insights into our understanding of how the circadian clock controls rice response to salt stress.

A new demethylase gene, OsDML4, is involved in high temperature-increased grain chalkiness in rice.

High temperature (HT) can affect the accumulation of seed storage materials and cause adverse effects on the yield and quality of rice. DNA methylation plays an important role in plant growth and development. Here, we identified a new demethylase gene OsDML4 and discovered its function in cytosine demethylation to affect endosperm formation. Loss of function of OsDML4 induced chalky endosperm only under HT and dramatically reduced the transcription and accumulation of glutelins and 16 kDa prolamin. The expression of two transcription factor genes RISBZ1 and RPBF was significantly decreased in the osdml4 mutants, which caused adverse effects on the formation of protein bodies (PBs) with greatly decreased PB-II number, and incomplete and abnormally shaped PB-IIs. Whole-genome bisulfite sequencing analysis of seeds at 15 d after pollination revealed much higher global methylation levels of CG, CHG, and CHH contexts in the osdml4 mutants compared with the wild type. Moreover, the RISBZ1 promoter was hypermethylated but the RPBF promoter was almost unchanged under HT. No significant difference was detected between the wild type and osdml4 mutants under normal temperature. Our study demonstrated a novel OsDML4-mediated DNA methylation involved in the formation of chalky endosperm only under HT and provided a new perspective in regulating endosperm development and the accumulation of seed storage proteins in rice.

Higher affinity of polyphenol to zein than to amyloid fibrils leading to nanoparticle-embed network wall scaffold to construct amyloid fibril-zein-EGCG hydrogels for coating of beef.

Globally, 800 million are undernourished and 2 billion are deficient in micronutrients. A regular dietary intake of meat is one of effective strategies to fight against undernourishment and deficiency of micronutrients. However, meat is a typical perishable food; proper handling to extend the shelf life of meat is required. In the present study, homogenous hydrogels composed with high contents of lysozyme amyloid fibrils, zein and green tea polyphenol epigallocatechin gallate (EGCG) were developed via the orchestration of protein-protein interaction and polyphenol-protein interaction for coating of beef. The protein-protein interaction between amyloid fibrils and zein showed higher affinity than that of the polyphenol-protein interactions. In addition, polyphenol EGCG was found to be more inclined to bind with zein than to the amyloid fibrils. Thus, the amyloid fibrils performed as the scaffold, in which EGCG on one hand induced the zein aggregate nanoparticles and on the other hand deposited on the surface of amyloid fibrils, leading to the dense multi-pore network with the nanoparticle-embed wall. It served as the microstructure mechanism for the enhanced gel strength. Coating of fresh chilling beef with the amyloid fibril-zein-EGCG hybrid hydrogels effectively protected the freshness and tenderness through inhibiting the over-growth of microorganisms and oxidation of lipid. This study paves the way to develop functional edible biomaterials via polyphenol induced coordination of the protein-protein interaction and polyphenol-protein interaction, where polyphenol acts as the molecular glue. This strategy shows high application potentials in health promotion related fields, including edible coating to extend the shelf-life of fresh meat.

The effect of additives combination on rheological properties of dough and quality of bread with Agaricus bisporus powder.

The bread with Agaricus bisporus powder has the defects of poor texture and taste, so it is necessary to optimize the appropriate additives in order to improve its quality. The purpose of this study was to evaluate improvement of the combination of vital wheat gluten, sucrose fatty acid esters and cellulase on the improved Agaricus bisporus powder bread (IABPB), with wheat bread (WB) and bread with Agaricus bisporus powder (ABPB) as control. The results of rheological properties indicated the dough samples improved with three improvers had higher solid-like behaviour than the control sample. The results of nutritional quality analysis showed that the protein and dietary fiber content of IABPB was higher than those of WB and ABPB, but the fat content was relatively low. In addition, the additives combination could effectively improve the baking quality of ABPB. Compared with ABPB without additives, the specific volume increased by 21.22%, the brightness of bread crumb increased by 8.75%, but the crumb hardness decreased by 32.57%. Furthermore, the study on texture property and water migration during the storage showed that the addition of three improvers could delay the aging of bread. Therefore, it was feasible to use additives combination as a special quality improver for ABPB, which could effectively improve its quality.

Controlled release and antioxidant activity of chitosan and ß-lactoglobulin complex nanoparticles loaded with epigallocatechin gallate.

In order to investigate the influence of different embedding methods on the properties and function of polyphenols, the Epigallocatechin gallate (EGCG) loaded chitosan nanoparticles prepared with or without ß-lactoglobulin (ß-Lg) were obtained by ionic cross linking method. The average particle sizes of EGCG loaded chitosan nanoparticles (EGCG-CS NPs) decreased from 190 nm to 157 nm after adding with ß-Lg, whereas the encapsulation efficiency (EE) increased from 59.79 % to 76.29 %. The results of transmission electron microscopy (TEM) showed that the obtained nanoparticles had obvious core-shell structure. The results of simulated gastrointestinal digestion showed that the release rate of EGCG in CS/ß-Lg NPs was much lower than that of CS-NPs. Compared with free EGCG, the DPPH and FRAP assay showed that EGCG-CS NPs and EGCG-CS/ß-Lg NPs had slow-controlled antioxidant activity. Meanwhile, the study of cellular antioxidant activity (CAA) showed that the EC50 values of EGCG-CS NPs and EGCG-CS/ß-Lg NPs were decreased by 8.56 % and 18.35 %, respectively.

Effect of sodium alginate and carboxymethyl cellulose edible coating with epigallocatechin gallate on quality and shelf life of fresh pork.

The active edible coatings were prepared by incorporating epigallocatechin gallate (EGCG) into sodium alginate (SA) and carboxymethyl cellulose (CMC) to investigate the effect of SA-CMC-EGCG coatings on quality and shelf life of fresh pork stored at 4 ±â€¯1 °C for 7 days. The antioxidant effects against lipid oxidation (TBARS), total volatile basic nitrogen (TVB-N) and antimicrobial activity against total viable counts (TVC) were analyzed. Besides, the changes in color parameters and sensory attributes of all pork samples were evaluated. The results showed that fresh pork coated with SA-CMC edible coating with EGCG had a significant inhibitory effect on its microbial growth (P < 0.05), lipid oxidation and TVB-N. SA-CMC-EGCG also increased the L* value and maintained a* value of pork during storage. Besides, the sensory scores of pork samples coated with SA-CMC-EGCG were significantly improved (P < 0.05). Therefore, using SA-CMC-EGCG edible coating could prevent decay and significantly increase the shelf life of fresh pork.

Mixolab behavior, quality attributes and antioxidant capacity of breads incorporated with Agaricus bisporus.

At present, some breads rich in edible mushrooms are more popular to meet the needs of functional bread products. In this study, different proportions of Agaricus bisporus powder (0, 2, 4, 6, 8%) were added into wheat flour to prepare bread, and their Mixolab behavior, bread quality and antioxidant capacity were studied. The results showed that the addition of Agaricus bisporus powder diluted the gluten in the flour, destroyed the dough matrix, which changed the water absorption of dough, the gelatinization and retrogradation of starch on the Mixolab. Meanwhile, the results of specific volume, texture and color measurement showed that addition of Agaricus bisporus powder reduced the specific volume of bread, deteriorated the texture and darkened the crumbs. In addition, the higher proportion of Agaricus bisporus powder, the higher total phenolics content and antioxidant ability of compound bread. However, sensory analysis showed that the overall acceptability of breads was relatively high after adding a small amount of Agaricus bisporus powder. Our results showed that breads containing about 4% Agaricus bisporus powder had higher antioxidant capacity and better sensory acceptability.

Preparation and antioxidant activity of sodium alginate and carboxymethyl cellulose edible films with epigallocatechin gallate.

The active edible films were prepared by incorporating epigallocatechin gallate (EGCG) into sodium alginate (SA) and carboxymethyl cellulose (CMC). The effects of EGCG addition on the physical and morphological properties of SA-CMC films were evaluated. Meanwhile, the release characteristics of EGCG from edible films and its antioxidant activity in fat food simulant (95% ethanol) were also detected. The results showed that the addition of EGCG could improve the tensile strength (TS) of edible films and reduce their elongation at break (E). Especially, the color of edible film added with EGCG deepened and the transmittance decreased. Scanning electron microscopy (SEM) images displayed that the films were dense and compact with a little roughness. Fourier transform infrared spectroscopy (FTIR) analysis indicated that the incorporation of EGCG into SA-CMC caused interactions occurring between SA-CMC and EGCG. In addition, the release and DPPH radical scavenging assay of incorporating EGCG in SA-CMC films showed that the obtained SA-CMC films with high EGCG content could release EGCG slowly and had strong antioxidant activity in fatty foods. Thus, incorporating EGCG into SA-CMC film was an effective way in order to develop active and environmental friendly packing materials for food industry.