Pigments are responsible for many of the beautiful colors that we see in the plant world. For instance lycopene is the red pigment responsible for the color of tomatoes. Also spinach leaves contain mainly chlorophyll-a, chlorophyll-b, β-carotene and smaller amount of lutein which is better known as vitamin A. Recent epidemiological studies have suggested that the consumption of tomato and spinach reduce the risk of cancer such as prostate, breast, stomach. The chlorophyll-a and beta-carotene pigments were isolated by column chromatography with alumina (Al2O3) stationary phase as polar absorbent which was suitable for chromatography of less polar compounds and hexane as mobile phase. Thus it makes non-polar beta-carotene pigments to elute faster. In the other hand more polar pigments such as chlorophyll-a make strong interactions and hence it remained more time in the column. Therefore, once β-carotene is eluted, a more polar solvent mixture of hexane-acetone(90:10) is used to elute the more polar chlorophyll-a. Acetone is more polar than hexane as it has a net dipole moment.
Moreover, the lycopene pigment in tomato paste was isolated by separating funnel which is used for the separation of components of a mixture between two immiscible liquid phases.