Saccharification of carrot pomace and use as nutrient source for the production of ꞵ-cryptoxanthin by Pantoea anthophila FL1_IS5

Abstract

Carrot pomace represents a rich source of nutritional components such as polysaccharides, dietary fiber, phenolic compounds, and ꞵ-carotene, which can be utilized as alternative sources to produce value-added products. In this research, carrot pomace was hydrolyzed to release monosaccharides and utilized to produce ꞵ-carotene and ꞵ-cryptoxanthin. The hydrolysate obtained from 10% solid loading (w/v) and a hydrolysis time of 48 h contained glucose, xylose, and ꞵ-carotene at 39.02 g/L, 26.63 g/L, and 26.65 mg/L, respectively. This hydrolysate was supplemented as a co-substrate in the cultivation to increase cell biomass and carotenoids production by the bacterial strain Pantoea anthophila FL1_IS5. Optimization of the medium composition and the initial pH revealed that the cell biomass, ꞵ-carotene, and ꞵ-cryptoxanthin reached concentrations of 5.74 g/L, 73.86 mg/L, and 31.87 mg/L, respectively, with 22.93% (v/v) carrot pomace hydrolysate and 0.51% (w/v) yeast extract, with the initial pH 7.44. This finding indicates that glucose, xylose, and ꞵ-carotene from carrot pomace hydrolysate can be used to produce ꞵ-cryptoxanthin by P. anthophilia, offering new opportunities for the valorization of carrot pomace.