Development of enzyme-based rapid screening methods for bioactive constituents in plant extracts

In recent years, there are more and more researches with developments of hyphenated techniques for the rapid identification of antioxidants in complex plant extracts, but the limitations for this on-line analysis may be critical to control the stability and activity of biological reactions [1]. A rapid method for detection and identification of antioxidant compounds in plant extracts was developed by a combination of microplate array analysis using xanthine oxidase, tyrosinase, lipoxygenase as models and HPLC [2,3]. As for the enzymatic reaction with plant extracts, the activity of the enzyme can be kept stable under the experimental conditions. With this simple and rapid method, we can estimate the required minimum screening dose of enzyme for bioactive constituents from plant extracts by HPLC. In addition to the reversible inhibitory effect of enzyme on plant extracts demonstrated by both microplate array analysis and HPLC, we will testify the irreversible inhibitory effect of enzymes with trace amounts of bioactive compounds by LC-TOF/MS.

References: 1. Tang, D. et al. (2008)J Sep Sci. 31:3519–26.

2. S. Zhu; S. et al. (2006) Fitoterapia 77:100–108.

3. Chen, C.H. et al.(2009) Molecules 14: 2947–2958.