Quantitative production of carotenoid and plasmid stability of Escherichia coli JM 109 pCAR25 Recombinant

Abstract

Abstract Carotenoids are orange-to-yellow natural pigments found in many plant species and some microorganisms. Carotenoids was isoprenoid compounds and having diverse of biological function especially anti-carcinogenic activity and preventing chronic diseases. Natural carotenoid production levels are not yet competitive with carotenoid levels presently produced by fermentation, chemical synthesis or by extraction of plant materials. Erwinia uredovora is carotenoid producing bacteria use use mevalonate pathway, while E. coli was produced isoprenoid via non mevalonate pathway. A combination of isoprenoid genes from different organisms that follow diferrent branches of the pathway make it possible to produce carotenoid and increase carotenogenesis. The aims of the research are measuring carotenoid production from E. coli JM109 pCAR25 recombinant quantitatively. It is also examined whether plasmid stability would be involved in carotenoid production of recombinant. The research was carried out by examined microbial growth, carotenoid production and plasmid stability on E. coli JM109 pCAR25. The result shows that growth of recombinant was slower than wild type detected from the cell weight and indicating the existence of plasmids. The highest carotenoid production of recombinant was 165,25 g/g dcw at stationer phase. The stability of plasmid on E. coli JM109 pCAR25 was consistent until 80 generation but tend to slightly decrease for each generation. It was assumed that the decrease of plasmid stability does not affected carotenoid production on E. coli JM109 pCAR25 recombinant due to the need of carotenoid for survival of the organisms. Key word : carotenoid, plasmid stability, E. coli JM109 pCAR25, E. uredovora