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The enzymatic degumming process of crude corn oil using phospholipase C from Thielavia terrestris was studied.The key factors affecting the enzymatic degumming efficiency of crude corn oil,including enzyme dosage, volume ratio of NaOH to citric acid, reaction temperature and reaction time, were optimized by a single-factor experiment with the content of phosphorus in corn oil as the evaluation index.The results showed that the optimal enzymatic degumming conditions were: enzyme dosage of 5000 U/kg,volume ratio (NaOH to citric acid) of 4, reaction temperature of 35 ℃ and reaction time of 1 h.Under the optimized conditions, the phosphorus content was reduced from 102.7 mg/kg to 24.0 mg/kg, with a hydrolysis rate of 76.6%.

• A mutant glycoside hydrolase family 134 β-mannanase was expressed in Pichia pastoris. • m Rm Man134A showed good pH stability, thermostability, and cold-activity. • Cassia gum was used as substrate for production of manno-oligosaccharides. • Seven components were separated from the hydrolysate of cassia gum. • Prebiotic activity of manno-oligosaccharides was tested with fourteen probiotics. To produce manno-oligosaccharides from cassia gum, a mutated glycoside hydrolase family 134 β-mannanase gene (mRmMan134A) from Rhizopus microsporus var. rhizopodiformis F518 was expressed in Pichia pastoris and a high expression level (3680 U mL−1) was obtained through high cell density fermentation. m Rm Man134A exhibited maximum activity at pH 5.5 and 50 °C. It was then subjected to hydrolyze cassia gum with 70.6% of overall yield of manno-oligosaccharides. From the hydrolysate, seven components (F1–F7) were separated and identified as mannose, mannobiose, galactose, mannotriose, mannotetraose, 61-α- d -galactosyl-β- d -mannobiose, and mannopentaose, respectively. According to in vitro fermentation, the manno-oligosaccharides were able to promote the growth of three Bifidobacterium strains and six Lactobaillus strains with 3.0-fold increment in culture absorbance, and these strains preferred manno-oligosaccharides with degree of polymerization (DP) 2–3 rather than those with DP 4–5. Novel manno-oligosaccharides from cassia gum with promising prebiotic activity were provided in the present study. [ABSTRACT FROM AUTHOR]

The family 10 xylanase (XynB) from Thermotoga maritima MSB8 is extremely thermostable and great potential in the applications of various fields of industry. The gene mxynB(64) was amplified by the method of PCR with the template of the genomic DNA of Thermotoga maritima MSB8, and cloned into the expression vectors of Escherichia coli and Pichia pastoris respectively. Xylanase B(40kD) was successfully expressed by the two heterologous protein expression systems with high-level production. The recombinant protein of XynB expressed in Pichia pastoris showed extreme thermostability and pH stability, which was optimally active at 90 degrees C and quite stable over the pH range of pH 5.0-10.8 at 70 degrees C. After incubation of the enzyme at 100 degrees C for 30 min, XynB retained 70% higher residual activity. The recombinant XynB expressed in Pichia pastoris is of great use in a variety of industrial and agricultural applications.