Abstract: Cymbopogon flexuosus (Nees ex Steud) Wats mutant cv. GRL-1 leaves obtained from different developmental stages (10 to 50 d) were fed in vivo with 5 μCi μmole-1 [2-14C]- acetate (activity 0.1 mCi, specific activity 34.51 mCi/mmole). The essential oil, geranyl acetate and geraniol (free + bound geraniol as part geranyl acetate) biosynthesis was at peak during the initial (10-20 days) leaf developmental stages. The ratio of relative % distribution of label incorporated into geranyl acetate to that of geraniol decline substantially during leaf development (10 to 50), thereby suggesting the role of geranyl acetate esterase (GAE) in transformation of geranyl acetate to geraniol. Also, it could be said that acetylation capacity of the leaves was maximum during initial growth phase. The relative % distribution of label incorporated in geraniol (as part of geranyl acetate) and acetate moiety isolated after hydrolysis of geranyl acetate have shown that bound geraniol biogenesis was maximum at 10 days and in later stages there was no enhancement in the label incorporation. At 50 days most of the radioactivity was appeared in free geraniol as at this stage acetylation capacity of the leaves was virtually negligible. The study revealed that only young and rapidly expanding leaves have the capacity to synthesize essential oil through cytosolic aceate-mevalonate pathway.
Deepak Ganjewala and Rajesh Luthra, 2007. Essential Oil Biosynthesis and Metabolism of Geranyl Aceate and Geraniol in Developing Cymbopogon flexuosus (Nees ex Steud) Wats Mutant cv. GRL 1 Leaf. American Journal of Plant Physiology, 2: 269-275.