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A b s t r a c t A r t i c l e I n f oA novel technology for rapid identification of Machilus Nees species using the visiblenear infrared spectrum (300-1100 nm) is described in this study. The reflectivities of new leaves of seedlings from 9 species of the genus Machilus Nees were collected. Stepwise discriminant analysis was applied to the spectral information of the leaves, and 18 unique bands were selected from 126 bands total. After obtaining the spectral information for the unique bands, the Bayesian discriminant method was applied to establish the discriminant analysis model for Machilus Nees species. According to the discrimination model, combinations of 6, 12, and 18 unique bands were selected, and the discrimination accuracies of 180 training samples reached 76.111%, 83.889%, and 93.889%, respectively, while the accuracies of 90 testing samples were 77.778%, 84.444%, and 95.556%, respectively. These results validated the discrimination model for Machilus Nees species constructed from the spectral information of 18 selected unique bands. The application of visible-near infrared spectrum technology combined with discriminant analysis could provide a novel approach for the rapid and accurate identification of Machilus Nees species.

The rumen of ruminants contains a variety of fungi capable of producing xylanases to break down plant cell walls. In this study, a new GH10 xylanase gene ArXyn10c20 from anaerobic rumen microorganism Anaeromyces robustus was successfully expressed in Pichia Pastoris GS115, with a protein molecular weight of approximately 42 kDa and showed the similarity by 64.08% with the β-Xylanase form Neocallimastix Californiae. The optimal pH and temperature for ArXyn10c20 was 5.5 at 40℃. ArXyn10c20 was stable in the pH range 5.0 – 9.0 for 1h which the residual enzyme activity was all above 75%. The activity of recombinant xylanase was significantly enhanced by 1 mM Cu 2+ . The products of ArXyn10c20 hydrolysis of beechwood xylan were xylobiose, xylotriose and xylotetraose by TLC analysis. In food applications, ArXyn10c20 can significantly improve the quality of dough and bread. With the addition of 7.5 mg ArXyn10c20, the hardness, gumminess and chewiness of the bread decreased by 42.24%, 45.33% and 55.36% respectively and the reducing sugar increased by 18.67%. The new discovered xylanase ArXyn10c20 has great potential in food industry.