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Microbial nitrogen (N) immobilization, which typically results in soil N retention but based on the balance of gross N immobilization over gross N production, affects the fate of the anthropogenic reactive N. However, global patterns and drivers of soil gross immobilization of ammonium (I

Summary The effects of pepsin hydrolysis on the β-conglycinin aggregates formed by heat treatment at different pH were investigated. Results showed that fibrils were still observed, whereas the random aggregates were easily to be digested in the simulated gastric fluid. Electrophoresis and molecular weight analysis indicated that large aggregates still existed after pepsin treatment for fibrils. Hydrolysis resulted in changes in the apparent viscosity (ηapp) of 6% fibril solutions. The ηapp at the shear rate range (0–30 s−1) increased in the order of fibrils

Summary This work focused on the effect of glycosylation on the gelation ability of β-conglycinin induced by microbial transglutaminase (MTGase). Rheological results indicated that the gels of β-conglycinin-dextran conjugate products exhibited higher G′ value (172.2 ± 8.6 Pa) compared with those of dry-heated β-conglycinin (75.2 ± 5.1 Pa), β-conglycinin (53.3 ± 4.0 Pa) and β-conglycinin-dextran mixture (38.6 ± 2.6 Pa) after 4 h incubation with MTGase. The gels prepared from β-conglycinin-dextran conjugate products had higher hardness, fracturability, springiness and cohesiveness values determined by textural profile analysis. The turbidity of β-conglycinin-dextran conjugate products solution incubated with MTGase increased faster than those of the other three protein samples. The conjugated dextran in β-conglycinin-dextran conjugate products could inhibit extensive protein–protein interactions which might result in the formation of more ordered and stronger gel network structures during MTGase cross-linking process. A compact and homogeneous gel networks in β-conglycinin-dextran conjugate products gels were also observed by scanning electron microscopy.

Summary Soy protein isolate (SPI)–maltodextrin (MD) conjugates were synthesised using Maillard reaction under high-temperature (90, 115 and 140 °C), short-time (2 h) dry-heating conditions. The loss of free amino groups in proteins and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) profile confirmed that SPI-MD conjugates were formed and higher dry-heated temperatures could increase the glycosylation degree. The emulsifying properties of SPI and SPI-MD conjugates were evaluated in oil-in-water emulsions. The emulsions stabilised with SPI-MD conjugates synthesised at 140 °C exhibited higher emulsifying stability and excellent storage stability against pH, ionic strength and thermal treatment compared with those synthesised at 90 °C, 115 °C and SPI stabilised emulsions. This might be due to a greater proportion of conjugated MD in SPI-MD conjugates synthesised at 140 °C because of the higher glycosylation degree, and more conjugated MD on the droplet surface could provide steric effect and enhance the stability of the droplets in the emulsions.

Five new sesquiterpenoids Nardosinanone A–E (1–5), were isolated from the extract of Nardostachys chinensis, and their structures were determined by extensive spectroscopic analysis. Compound 1 featured a nardosinane sesquiterpenoid with an unusual tricyclic skeleton. Compounds 2–4 were new nardosinane sesquiterpenoids bearing a rare 10,11-epoxy group. The absolute configurations were determined by single-crystal X-ray diffraction analysis, ECD calculation method, the CD analysis of the in situ formed [Rh2(OCOCF3)4] complex, and the CD data analysis based on the octane rule of cyclohexanone.