초록
This work was conducted to use palm date wastes in the production of carotenoids. Three strains of Lactobacillus plantarum (QS1, QS2 and QS3) were isolated from food samples including bakery's yeast, olive fermentation and cheese. Strains were investigated for their structural recA gene by PCR. The recA gene was successfully amplified from all strains under study. The ability of isolated L. plantarum strains to produce carotenoids in MRS broth was investigated. QS3 isolate gave the highest ability for production of carotenoids. Statistical screening of media components for production of carotenoids by L. plantarum QS3 using date syrup as a source of sugar was carried out using Plackett-Burman design. Date syrup at 5% sugar concentration produced 16.21mg/kg dry cell of carotenoids when used alone. Increase in carotenoids production was recovered (54.89mg/kg dry cell) with supplementation of MRS medium with salts and organic nitrogen after optimization of pH and temperature using date syrup as a carbon source. Plackett-Burman design showed peptone, K<SUB>2</SUB>HPO<SUB>4</SUB>, sodium acetate and date juice as main components affecting carotenoids production.