Enhancing oleic fatty acid content in cotton seed oil

Germplasm and Genetic Stocks

poster

Bhariya, Sanjaykumar ; HIREMATH, VAMADEVAIAH; KATAGERI, I S; P U, KRISHNARAJ

HIREMATH, VAMADEVAIAH

HIREMATH, VAMADEVAIAH

Global cottonseed output is estimated around 35 million tons in the recent past. Major producers of cotton in the world also dominate the oil sector with China, U.S., India, Pakistan and Brazil are leading. Out of this, nearly 27 million tons are used for oil extraction. Global trade in cotton oil is estimated around 1 million tons. Australia, U.S. and Mexico are the leading exporters of cottonseed oil while Europe and Japan are mail importers. Cottonseed oil is estimated to contribute nearly a fifth of the global vegetable oil production. Cotton seed is a byproduct derived through process called ginning. Cotton seed oil is extracted from cottonseed, which contain around 18-20 per cent oil. This pale yellow oil is generally used for cooking. Cottonseed oil is further refined to remove gossypol, a naturally occurring toxin that protects the cotton plant from insect damage. Oil thus obtained, is used in combination with other oils to produce many vegetable oil products. Composition of cotton seed oil is about 26% Palmitic acid (C16:0) 15 per cent oleic acid (C18:1) and 58 per cent linoleic acid (C18:2). Even through palmitic acid provides stability to the oil during deep frying applications but it leads to low den try lipoproteins subsequently to the greater risk of cardiovascular disease. High level of linoleic acid (50%) is also undesirable because of its oxidative instability. It is therefore it is desirable to develop cottonseed oil higher mano unsaturated fatty acid with thermal stability and better shelf life which is more suitable for deep frying without any rancidity and off flavors. In this study, an attempt was made to develop construct for silencing of 12 desaturase gene, and analyse its expression in cotton plants. A 600 bp DNA fragment was amplified using 12 desaturase gene specific primer from cotton ovules after 30 days pollination. The amplicon was cloned in pTZ57R/T and transformed into E. coli DH5a. Transformants were confirmed through PCR and restriction analysis. The analysis of the sequence revealed maximum of 100% homology at nucleotide and 100% homology at amino acid level with reported sequence in the database (AF270425). Partial sequence of delta 12 desaturase gene was cloned in both sense and antisense direction in generic ihp vector. The expression cassette carrying insect from generic ihp vector was then subcloned into plant transformation vector pCAMBIA 1305.1 to facilitate plant transformation. The recombinant clones were then mobilized into Agrobacterium tumefaciens LBA4404 by tri parental mating then transformed into cotton plants. Callus was analyzed through histochemical analysis of gus gene expression against control plants.