Molecular Regulation of the Metabolic Pathways of the Medicinal Plants: Phyla dulcis

Godson O. Osuji^*, Aruna Weerasooriya, Peter A. Y. Ampim, Laura Carson, Paul Johnson, Yoonsung Jung, Eustace Duffus, Sela Woldesenbet, Sanique South, Edna Idan, Dewisha Johnson, Diadrian Clarke, Billy Lawton, Alfred Parks, Ali Fares, Alton Johnson

Plant Systems Research Unit, College of Agriculture and Human Sciences, Prairie View A & M University, Prairie View, USA.

DOI: 10.4236/ajps.2015.611171                

Abstract

Phyla (Lippia) dulcis contains hernundulcin sesquiterpene zero-caloric sweetener that is about a thousand times sweeter than sucrose, and also bitter constituents including camphor and limonene. There is yet no simple method to remove the undesirable constituents. The yield of sweetener hernundulcin is very low, and there is no simple method to maximize its composition. The aim of the project was to characterize the mRNA targets that regulate the primary and terpenoid metabolic enzymes of P. dulcis. Restriction fragment differential display polymerase chain reaction of P. dulcis glutamate dehydrogenase-synthesized RNA showed that many mRNAs encoding β-caryophyllene, (+)-epi-α-bisabolol, bicyclogermacrene, bifunctional sesquiterpene, and geraniol synthases shared sequence homologies with ribulose-1,5-bisphophatase carboxylase, granule-bound starch synthase, pyruvate kinase, glucose-6-phosphate dehydrogenase, and phosphoenol pyruvate carboxylase. Sequence similarities between mRNAs encoding primary metabolic enzymes and terpene synthases suggested that photosynthesis could regulate terpenoid metabolism in order to increase the yield of sweetener hernundulcin.

Keywords

Hernundulcin Sweetener, Primary Metabolism, Terpene Synthase mRNA, Glutamate Dehydrogenase

Conflicts of Interest

The authors declare no conflicts of interest.

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