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With increased interest in the biodegradation of lignin, there is a pressing need to evaluate the feasibility of using microorganisms for lignin degradation. A novel Bacillus strain was separated from compost and identified as Brevibacillus thermoruber. B. thermoruber showed excellent performance in lignin degradation and degraded 81.97% of lignin after 7 d, which was similar to the lignin degradation rate of fungi. The biodegradation of lignin G and H monomers mainly proceeded via the β-ketoadipate pathway at 37 °C. At 55 °C, the degradation product of lignin S monomer was mainly a benzoic acid substance, indicating that the lignin was degraded via the benzoic acid pathway. The degradation products of lignin are important precursors for humus formation in compost. The results of this study provide new insights into the biodegradation pathway of lignin in different stages of composting.

This research investigated the effects of wheat bran (WB) particle size on the dough and final productions of instant fried noodles. With the decrease of particle size (from 487.9 to 148.5μm), the pasting properties gradually increased and the solvent retention capacities (SRC) of the dry mix were improved and the values of elasticity modulus (G’) and viscous modulus (G’’) of the noodle dough increased significantly. The SEM micrographs of noodle dough showed the more uniform starch granule structure could be formed with smaller WB particle. Moreover, the reduction of particle size gave the fried noodles a slightly darker surface, harder texture and weaker adhesiveness. Most importantly, the oil content of fried noodles decreased from 26.50% to 19.77% with the decrease of particle size. All the results indicated that the decreasing WB particle size reduce the negative effects of WB on the properties of dough and the qualities of noodles.

Cereal grains are generally subjected to thermal treatment before consumption. However, few data are available on total phenolic content (TPC), degree of starch gelatinization, phenolic acids, and antioxidant capacity of extruded whole grains based on trolox equivalent antioxidant capacity (TEAC), DPPH radical scavenging activity, and ferric reducing antioxidant potential (FRAP). Four whole grains, brown rice, wheat, maize, and barley were examined in this study. The free and bound TPCchanged significantly (p < 0.05) after extrusion. Morever, heat and degree of starch gelatinization could affect the bound TPC. In bound fraction, the antioxidant capacity was directly influenced by TPC. Extrusion (110-140°C) can retain or improve the antioxidant capacity in its free and bound fractions. Phenolic acids are stable in their bound form. Results showed that the bound TPC and total phenolic acids have a strong relationship against antioxidant capacity, indicating that TPC is the major antioxidant in the bound fraction.