Using Bromelain in Pineapple Juice to Investigate Enzyme Function

 

William V. Glider and Mark S. Hargrove

Tested Studies in Laboratory Teaching, 2002, Volume 23

Abstract

This investigation introduces students to the structure and function of the proteolytic enzyme, bromelain, which is present in large quantities in the fruit, leaves, and stems of pineapple. In this lab exercise, students study the rate at which bromelain catalyzes the hydrolysis of gelatin (substrate) at different temperatures and pHs. Strips of developed black and white photographic film are placed in freshly squeezed pineapple juice under different experimental conditions. The time it takes for the film to clear is used as an indicator of the rate at which bromelain catalyzes the hydrolysis of the substrate (gelatin), which binds the black silver grains to the plastic backing of the film. This lab exercise has been used in traditional non-majors and mixed majors/non-majors General Biology labs and can easily be adapted to an investigative approach.

Keywords:  enzyme, enzyme assay, pineapple enzyme, bromelain, enzyme activity

University of Chicago (2001)