A newly discovered natural red pigment

Having an interest in unusual fruits, I recently spotted some research about fruits from the Basella alba plant that could provide a new source of natural colour and antioxidants.

The plant is commonly grown as a leafy vegetable in Taiwan, particularly during the summer season when the production of other leafy vegetables is short.

Grown into the autumn and winter seasons, the vines produce a substantial quantity of fleshy and dark blue fruits, which are usually discarded by farmers.

Researchers from the National Chiayi University, Taiwan, have analysed the fruit’s red-violet pigments. The major red pigment was identified as gomphrenin I, which increases in concentration as the fruit ripens.

Gomphrenin I belongs to a group of water-soluble, nitrogen-containing natural pigments known as betalains, which provide a wide range of colours in leaves, fruits and roots as well as being involved in plant adaptation to stress. Largely because of their restricted occurrence in nature, betalains have not been as extensively studied as pigments in the way that anthocyanins, carotenoids and chlorophylls have.

Among the sources of betalains that have been studied, such as beetroot, amaranth plants and Swiss chard, some have been found to contain pigments that have antioxidant and cancer prevention activities as well as colouring properties.

When compared with reference antioxidants such as ascorbic acid, gomphrenin I was also found to be highly potent. It was also found to have marked anti-inflammatory activity.

If further research confirms these properties, Basella alba fruits could find a use as nutraceuticals and also as food colourants.