Differential gene expression of pectin esterase and changes in pectin during development and ripening stages of fruit in selected cultivars of banana

Abstract Pectin is a very important ingredient in food processing. The present study was designed to find out the changes taken place in pectin content during development and ripening phases of banana fruit. The expression of gene (pectin esterase) was also observed during development and ripening. Five exotic cultivars namely William, Brazilian, G-Naine, Basrai and Pisang were selected for this study. Sampling were carried out after every 2 weeks during development and there was 6 sampling stages (from emergence to harvesting stage). After harvesting the fruit of all cultivars were subjected to natural ripening in the lab and sampling during ripening were carried out according to the colour changes in the fruit skin. 5 ripening stages were studied. Hence total number of 11 stages were studied during development and ripening. The sequence of pectin esterase were obtained from NCBI, primers were designed and procured. RNA was extracted from each cultivar and expression analysis of pectin esterase was carried out. It was found that the expression of gene is variable during the development and the ripening stages in each cultivar. Similarly, the pectin content were also significantly variable during development and ripening of fruit. The variation was also found among the cultivars. It was concluded that unripe banana have more pectin content then ripe banana and the pectin content of the fruit is associated with expression of the gene.