In order to investigate the relationships among β-mannanase,β-mannosidase and α-galactosidase required for degrading galactomannan in cell wall during and following rice seed germination,the activities of the three enzymes and the effects of ABA and GA3 on them were detected.

By using the method of PCR-based cDNA library screening, two β-mannosidase clones, GhManAl and GhManA2, had been isolated.

To characterize the precise function ofβ-mannosidase in cotton fiber, in this study,the sense and antisense coding sequence of theβ-mannosidase gene were fused withfiber-specific E6 promoter to build the constructs of sense gene and antisense RNA gene,and with which to transform into cotton via Agrobacterium-mediated transfor.

The synthesis of β-mannoside and β-mannosamine poses one of the greatest challenges to the carbohydrate chemists,because the mechanism of forming mannoside or mannosamine,either neighboring group participation method or non-neighboring group participation method,leads predominately to the α-anomer.

This research used β-mannanase which was thermostablly,beared the acid and alkali beta to carry on the controllable degeneration to Pregelatinized Dtarch.

By introducing and localiz-ing mannosidases and glycosyltransferases into the yeast,the pathway of hyperglycosylation are effectively blocked.

The synthesis of β-mannoside and β-mannosamine poses one of the greatest challenges to the carbohydrate chemists,because the mechanism of forming mannoside or mannosamine,either neighboring group participation method or non-neighboring group participation method,leads predominately to the α-anomer.