Biochemical Analysis and DNA Barcoding of Millet Echinochloa frumentacea

Abstract

Background: Millets are small grains that are rich in nutrients. In recent times, millet-based foods have been increasingly recommended for a healthy diet. Many millets are not annotated or DNA barcoded yet. Methods: In this study, comparative biochemical analyses especially that of starch and total protein of Echinochloa frumentacea, called as Indian barnyard white millet (Varai), from geographically different locations like Tamil Nadu and Maharashtra have been done. Their DNA barcoding has also been done to identify them on the basis of molecular data. Result: It was observed that starch granules were more abundant in Tamil Nadu variety as compared to Maharashtra variety. Blue value, indicative of amylose: amylopectin ratio was found to be low in Varai, indicating that Varai has low starch digestibility and its starch releases glucose slowly, thus making it a low glycaemic index food. Protein content was higher in Tamil Nadu variety, but overall Varai had a lower protein content as compared to other millets. Ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene from plastid was isolated, amplified by PCR, sequenced and the sequence was submitted to GenBank, NCBI. The gene was identified to be that of Echinochloa frumentacea and was given the accession numbers by GenBank as OR027010 (Varai, Maharashtra) and OR027011 (Varai, Tamil Nadu). This study indicated a distinct biochemical difference related to the geographical location of millets. This study helped barcoding of Echinochloa frumentacea Indian varieties using rbcL gene. This will further help in studies of phylogeny and evolution and also that of the relatedness of Echinochloa sp within and as compared to other millets.