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Twenty-one compounds were isolated and elucidated from the roots of Rhodiola rosea L. , including two new compounds (1–2), along with nineteen known compounds (3 - 21), compounds 4 , 5 , 7 , 8 , 13 , 17 , 21 were isolated for the first time from Plants of the Sedum family and compounds 14 , 20 were separated for the first time from the genus Sedum. In the present study, the structures of the compounds were investigated by NMR spectroscopy by comparing the data with those reported in the literature. Moreover, all isolates were tested for their neuroprotective activities aga BV NM. C, inst CoCl 2 -induced injury in PC12 cells. As a result, compound 7 showed better neuroprotective effects with cell viability (56.56 ± 1.2)% at 20 μ M. [Display omitted] • A new phenolic compound and an aliphatic chain compound were isolated from Rhodiola rosea L. • Seven compounds were isolated from Plants of the Sedum family for the first time. • Two compounds were isolated from the genus Sedum for the first time. • Compound 7 (Mallonanosid A) had better neuroprotective effects with cell viability of (56.56 ± 1.2) % at 20 μ M. [ABSTRACT FROM AUTHOR]

To investigate the impact of different polyphenols on the gel properties of gellan gum (GG) and the interaction mechanism, experiments and virtual molecular simulations were conducted based on nine representative polyphenols. Rheological analysis revealed that all the GG/polyphenol composite hydrogels were pseudoplastic fluids with a low viscosity. The storage modulus (G′) of hydrogel containing only GG was 28.3 Pa at 0.1 Hz. The addition of gallic acid (GA), puerarin (PUE) or cyanidin cation (CC) significantly increased the G′ of the hydrogel by 4.9-fold, 3.3-fold, and 2.6-fold, respectively. The introduction of GA reduced the water holding capacity (WHC) of the hydrogel to 62.0 %, while the other eight polyphenols increased the WHC to nearly 100 %. Regular, intact and dense honeycomb mesh structures were observed in the GG/GA, GG/PUE, GG/CC and GG/catechin microstructures. The molecular docking results indicated that, among the nine polyphenols, PUE had the strongest affinity for GG with an interaction energy of −18.64 kcal/mol. According to the results of molecular dynamics simulation, the total energy of the composite system interacting with water corresponded well with the G′ of the composite hydrogels. The GG/GA system with the highest G′ had the lowest total energy of −15655.82 kJ/mol. Hydrogen bonds were the main driving force for improving the strength and maintaining the structural stability of the composite hydrogels. Therefore, this study confirmed the various effects of nine polyphenols on GG hydrogels and provided a novel basis for investigating the synthesis and gelation mechanism of polysaccharide-polyphenol composite hydrogels. [Display omitted] • The properties of GG hydrogel varied after mixed with different polyphenols. • Molecular docking elucidated affinity and binding modes between GG and polyphenols. • Relationship between gel strength and binding energy provided by MD simulations. • Hydrogen bonding played major roles in gel formation and binding process. [ABSTRACT FROM AUTHOR]

This study investigated the influence of heat treatment on the interaction of large yellow croaker (Pseudosciaena crocea) roe protein isolate (pcRPI) with curcumin (Cur), and heated pcRPI (HpcRPI)-Cur and pcRPI-Cur complexes were also prepared. Fourier transform infrared spectroscopy, fluorescence spectroscopy, and surface hydrophobicity analysis indicated that pcRPI and HpcRPI bind to Cur mainly by hydrogen bonds, van der Waals forces, and hydrophobic interactions, and compared with pcRPI, HpcRPI showed better binding effects with Cur. Molecular docking analysis also evaluated the binding site and the forces between vitellogenin, vitellogenin B and C in pcRPI and Cur. Furthermore, HpcRPI-Cur could form gels induced by glucono-δ-lactone (GDL), while pcRPI-Cur-GDL exhibited a fluid state. The HpcRPI-Cur-GDL gels showed great protective effects on Cur in the resistant gastrointestinal environment. These results indicated that heat treatment will improve the application of pcRPI as a functional material in the food field. [Display omitted] • The pcRPI can bind to curcumin via noncovalent interactions and form complexes. • The heat treatment promoted the noncovalent interactions of pcRPI with curcumin. • The heat treatment enhanced the formation of pcRPI cold-set gels. • The heated-pcRPI gel significantly improved the delivery effect of curcumin. [ABSTRACT FROM AUTHOR]

To develop composite hydrogels based on low acyl gellan gum (GG), the effect of puerarin (PUE) on the gel properties of GG was investigated. The results showed that the maximum storage modulus (G ′) of the 1.2 % GG/0.8 % PUE composite hydrogel was 377.4 Pa at 0.1 Hz, which was enhanced by 4.7-fold compared with that of 1.2 % GG. The melting temperature of this composite hydrogel increased from 74.1 °C to >80.0 °C. LF-NMR results showed that a significant amount of free water was present in the hydrogel matrix. The surface structure aggregation and the shrinkage of the honeycomb meshes in the composite hydrogel proved the cross-linking of PUE and GG. XRD, FTIR and molecular simulation results illustrated that hydrogen bonds were the most important factor controlling the interaction between GG and PUE. Thus, the GG/PUE composite hydrogel has good elasticity, thermal stability and water retention, which lays a good foundation for further application in the food industry. [ABSTRACT FROM AUTHOR]

In recent years, borophene has developed into an incredibly promising magnetic material that is essential to many industries including superconductivity and fuel cells. In this paper, using Monte Carlo simulation, the ground-state phase diagrams and magnetic properties of an Ising-type borophene monolayer are explored specifically. The results show that induced by crystal field and exchange coupling, the second-order magnetic phase transitions and the compensation temperature are obtained. Additionally, the multiple compensation temperatures and multi-loop hysteresis characteristics are observed, which are vital in multiple magnetic recording. • A mixed-spin Ising-type borophene monolayer was studied based on Monte Carlo simulation method. • The ground-state phase diagrams were discussed by Monte Carlo method. • The temperature dependence of the magnetization and the susceptibility were presented. • Multiple compensation temperatures were obtained. • Multiple-loop hysteresis behaviors were clearly observed in this system. [ABSTRACT FROM AUTHOR]

• Gellan gum (GG) improved gel formation of protein isolate from P. crocea roe (pcRPI). • GG improved the rheological properties and water holding ability of pcRPI gels. • The pcRPI-GG binary gels showed denser, more aggregated network structure. • GG improved the protective effects of curcumin by pcRPI gels with control release. The aim of this study was to investigate the effect of gellan gum (GG) on the cold gelation of large yellow croaker roe protein isolate (pcRPI). The water-holding ability and storage modulus of the pcRPI-GG binary gels increased with the GG concentration, where the storage modulus of the pcRPI-0.2% GG gel was approximately 30.7 times that of the pure pcRPI gel. Compare to the other binary gels, pcRPI-0.2% GG gels exhibited a lower lacunarity and higher junction density, with a denser, more aggregated microstructure. Consequently, curcumin was embedded in pcRPI-0.2% GG gels, and simulated gastrointestinal digestion test results showed that GG addition effectively protected and slowed curcumin release in the gastrointestinal environment. These findings may contribute to elucidating the interaction of pcRPI with GG and demonstrate the potential of binary gels for the embedding and delivery of active substances. [ABSTRACT FROM AUTHOR]

• Low-acyl gellan gum had effect on gelation of scallop male gonad hydrolysates (SMGHs). • Gel strength of SMGHs was increased with increasing of low-acyl gellan gum (GG) dose. • The thermal stability of SMGHs gel was improved by the addition of GG. • The promoting effect of GG on SMGHs gel was related to the water migration. • The SMGHs/GG composite gels showed a regular and homogenous network. This study aimed to examine the gelation and microstructural properties of scallop male gonad hydrolysates (SMGHs) in the presence of low-acyl gellan gum (GG) at different mass ratios. The rheological results showed that both elastic modulus and thermal stability of SMGHs were significantly improved by the addition of GG. Meanwhile, the relaxation time T 23 was significantly reduced in SMGHs/GG by low-field nuclear magnetic resonance, indicating a strong interaction between SMGHs and GG. Fourier transform infrared spectroscopy indicated the blueshift of amide I and II peaks in SMGHs/GG further demonstrated the electrostatic interaction between SMGHs and GG. The network structure of SMGHs/GG binary complexes was more compact and the surface was smoother than that of SMGHs by cryo-scanning electron microscopy. Furthermore, increasing the content of GG in the SMGHs/GG binary complex significantly reinforced the gel strength and promoted the gelation process. [ABSTRACT FROM AUTHOR]

Human activities have distinctly enhanced the deposition levels of atmospheric nitrogen (N) pollutants into terrestrial ecosystems, but whether and to what extents soil carbon (C) and N status have been influenced by elevated N inputs remain poorly understood in the 'real' world given related knowledge has largely based on N-addition experiments. Here we reported soil organic C (OC) and total N (TN) for twenty-seven forests along a gradient of N deposition (22.4–112.9 kg N/ha/yr) in the Beijing-Tianjin-Hebei (BTH) region of northern China, a global hotspot of high N pollution. Levels of soil TN in forests of the BTH region have been elevated compared with investigations in past decades, suggesting that long-term N deposition might cause soil TN increases. Combining with major geographical and environmental factors among the study forests, we found unexpectedly that soil moisture and pH values rather than N deposition levels were major regulators of the observed spatial variations of soil OC and TN contents. As soil moisture and pH values increased with mean annual precipitation and temperature, respectively, soil C and N status in forests of the BTH region might be more responsive to climate change than to N pollution. These evidence suggests that both N deposition and climate differences should be considered into managing ecosystem functions of forest resources in regions with high N pollution. Unlabelled Image • Soil OC and TN were investigated for forests in a global hotspot of N pollution. • Soil TN increased in forests of the BTH region during past decades. • Spatial variations of soil OC and TN were mainly regulated by moisture and pH. [ABSTRACT FROM AUTHOR]

Abstract Based on the daily precipitation data of Northeastern China (NEC), this research study utilized the monthly mean geopotential height field and vertical velocity field data obtained by NCEP/NCAR reanalysis. In addition, the monthly mean SST (sea surface temperature) data obtained by NOAA reconstruction, along with the calculations of NEC precipitation generated on the occurrence date of the annual early summer (June) northeast cold vortex (NECV) (hereinafter referred to as the cold vortex precipitation) were used to analyze the variation characteristics of cold vortex precipitation. The aim of this study was to explain the physical mechanism of the previous SST factors which had influenced the cold vortex precipitation through the force of atmospheric circulations, from the perspective of a statistical analysis. Finally, sensitivity tests of the AM2.1 atmospheric circulation model were conducted to verify the statistical analysis results. The results revealed that since 1961 there had been a significant increase trend in the early summer cold vortex precipitation. The relationships between the NEC early summer cold vortex precipitation and the previous SST were divided into three periods. During the period ranging from 1961 to 1979 (hereinafter referred to as Phase 1), a NAT anomaly positive phase during March to May resulted in the blocking highs of the Ural Mountains and the Sea of Okhotsk becoming strengthened (“dual blocking pattern”) in the early summer, which in turn led to increased early summer cold vortex precipitation. During the period ranging from 1980 to 2000 (hereinafter referred to as Phase 2), a higher Kuroshio SST in April to May stimulated an EU-like teleconnection pattern in the early summer over Eastern Asia. As a result, the cold vortex precipitation in early summer was reduced. After 2001 (hereinafter referred to as Phase 3), the NAT anomaly negative phase during March to May induced strengthened blocking patterns on the northwestern side of Lake Baikal in the early summer, which was accompanied by a strengthened northeastern cold vortex (a pattern of “higher in the north, lower in the south”). Also, an upward vertical velocity anomaly appeared over the NEC, which resulted in increased early summer cold vortex precipitation. The sensitivity tests of this study's numerical model reproduced the force effects of the Kuroshio SST in Phase 2, and the NAT in Phase 3 on the EU-like teleconnection pattern, and the pattern of “higher in the north, lower in the south”. These findings further corroborated the aforementioned results. Highlights • Since 1961 there had been a significant increase trend in the early summer cold vortex precipitation. • During 1961-1979, a NAT anomaly positive phase during March to May resulted in the “dual blocking pattern”. • During 1980-2000, a higher Kuroshio SST in April to May stimulated an EU-like pattern in early summer. • After 2001, the NAT anomaly negative phase in spring induced a pattern of “higher in the north, lower in the south”. • The sensitivity tests of this study’s numerical model reproduced the force effects provided by the statistical results. [ABSTRACT FROM AUTHOR]

A composite hydrogel composed of scallop (Patinopecten yessoensis) male gonad hydrolysates (SMGHs) and κ -carrageenan (KC) was fabricated with a designed microstructure to preserve curcumin (Cur) during the upper gastrointestinal tract (GIT). The presence of KC obviously increased the initial elastic moduli (8.2–761.8 Pa), shortened the relaxation time T 23 (517.37–420.10 ms) as well as caused the blue shift of the emission peak and quenched the intrinsic fluorescence of Cur in SMGHs/KC-Cur system, signifying the solid combination within SMGHs and KC. In addition, the red shift in O–H stretching bands and blue shift in amide I bands in SMGHs/KC-Cur further accentuated the involvement of hydrogen bonds and electrostatic interactions within SMGHs, KC and Cur. The disappearance of crystalline structures suggested the successful embedment of Cur in the hydrophobic core of SMGHs. Moreover, the microstructure of the hydrogels varied from heterogeneous with tattered large pore cavities and scattered patches to homogeneous distribution with dense mesh and solid network wall. These scenarios caused a more compact network of SMGHs/KC-Cur than SMGHs-Cur to protect Cur from releasing in simulated intestinal and simulated colonic phases with slower released rate, both of which had the final extent of Cur release exceeding 90%. Furthermore, cryo-SEM showed that the significant release of Cur from hydrogels in the simulated intestinal phase was due to SMGHs matrix erosion with even larger pore sizes, tattered network and thinner network wall. Therefore, it is suggested that SMGHs/KC hydrogels with biocompatibility and good tolerance to acid environment could be reliable and desirable soft materials to embed and deliver Cur to the colon, having potential applications in functional foods and biological therapeutic purposes. [Display omitted] - Enhancement of gel elasticity in SMGHs/KC confirmed a feasible Cur-loaded carrier. - Migration of water in SMGHs/KC to bound water direction supported the Cur embedment. - Compact and dense porous networks of SMGHs/KC contributed to the Cur embedment. - Better sustained release of Cur in SMGHs/KC promised the delivery of Cur in colon. [ABSTRACT FROM AUTHOR]