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Feruloyl esterases (FAEs) are essential accessory enzymes in the hydrolysis of plant cell wall structure. A novel FAE was obtained from Penicillium sumatrense NCH-S2. Enzyme purification was conducted by ultrafiltration, ammonium sulfate precipitation, anion exchange, and gel filtration chromatography. This FAE has a molecular mass of 36 kDa. Its optimum temperature and pH were 50°C and pH 9.0–10.0, respectively. The FAE demonstrated high pH stability at the pH ranging from 6.0 to 10.0. After enzymatic hydrolysis with FAE, the DPPH free radical scavenging capacity, ferrous ion chelating ability, and total phenolic content (TPC) of defatted rice bran (DRB) hydrolysate significantly increased. Furthermore, the amount of released FA from DRB under a synergistic interaction of FAE and hemicellulose increased by 18–21% in comparison with that of either enzyme acting alone.

The inferences of burden metallization rate on softening-melting dropping properties were investigated through softening-melting dropping test of three kinds of metalized burden pressure drop. The results indicated that the softeningmelting temperature interval of pre-reduction mixed burden is bigger than primeval mixed burden, the melting interval narrow with the rise of metallization rate of ferric burden as well as dropping temperature interval. The average pressure drop, maximum pressure drop and softening-melting dropping properties eigenvalue decrease with the rise of metallization rate of ferric burden. Besides, the dropping temperature of burden reduces with the rise of carbon content of molten iron. The combination high metalized burden and higher carbon content of molten iron is benefit to decreasing thickness of cohesive zone and improve permeability of cohesive zone.