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In this study, a combined whole-cell biotransformation process was used for efficient synthesis of optically pure (1 R, 2 S )-norephedrine [(1 R, 2 S )-NE]. The genes encoding R -selective acetohydroxyacid synthase I (AHAS I) from Escherichia coli and S -selective ω-transaminase (ω-TA) from Chromobacterium violaceum BCRC10636 were cloned and over-expressed in E. coli NovaBlue cells. In the first biosynthetic step, l -phenylacetylcarbinol ( l -PAC) was produced from benzaldehyde and pyruvate by using recombinant E. coli (pQE- AHAS I) cells, with almost 100% conversion yield and 71.8% purification yield. The purified l -PAC was coupled to l -alanine by using recombinant E. coli (pQE- CvTA ) cells to produce (1 R, 2 S )-NE. This biocatalytic process was optimal at pH 6.5 to 8.0 and 37 °C, with a 1:10 ratio of l -PAC to l -alanine. Under the optimal conditions, the highest conversion yield of (1 R, 2 S )-NE was 62.2% and the enantiomeric excess value of (1 R, 2 S )-NE was more than 99%. The recombinant E. coli (pQE- CvTA ) cells could be reused for at least 20 cycles, with only a modest reduction in the conversion yield to 76.3% relative to the first cycle. Our results indicate that the combination of AHAS I- and ω-TA-expressing E. coli cells might be a potential biocatalyst for (1 R, 2 S )-NE production.

To promote developing more usable and accessed, daily-used products that could meet the rigorous requirements from diverse consumers at the present time, this research proposed an innovative product design process by synergizing both universal design (UD) principles and TRIZ tools. This newly developed process started with stating the design problems via a UD evaluation, followed by PDMT analysis to develop the preliminary design directions. The directions were then analyzed by using Su-Field models in order to locate the potential resolutions from TRIZ’s 76 Standard Solutions. Finally, a case study was conducted to demonstrate how this innovative design process works. Study result shows that this approach can help identify the core of the problem and locate the improved product concepts effectively, resulting in generating more creative and usable product design.