Screening, identification, and characterization of high potential bacteria for ꞵ-cryptoxanthin production from natural sources

Abstract

ꞵ-Cryptoxanthin is a carotenoid compound that presents several benefits, including provitamin A, prevention of bone loss, anti-obesity, antioxidant activities, anti-inflammatory, and anti-cancer activity. Bacteria are microorganisms of significant interest for ꞵ-cryptoxanthin production due to their short cultivation times and high yields. In this study, we aimed to screen ꞵ-cryptoxanthin producing-bacteria, which were isolated from three different sources, including surface marine water, soil, and flowers. The isolated bacterium strain from Tecoma stans (yellow elder), with a yellow pigment colony that can produce ꞵ-cryptoxanthin, zeaxanthin, and ꞵ-carotene, was identified by 16S rRNA as Pantoea anthophila FL1_IS5 strain. The carotenoids produced by this strain were identified and quantified by high performance liquid chromatography (HPLC) and high-resolution mass spectrometry (LC-HRMS/MS). Furthermore, the whole genome sequencing of P. anthophila FL1_IS5 was analyzed to confirm the carotenoids synthesis pathway and revealed the presence of the genes idi and CrtBIEXYZ. The optimized concentration of glucose and yeast extract to be added as carbon and nitrogen sources, in nutrient broth (NB) medium (10 g/L and 5 g/L, respectively), resulted in the highest cell biomass of 2.03 ± 0.08 g/L and ꞵ-cryptoxanthin production at 10.59 ± 0.14 mg/L. These results indicate high potential for ꞵ-cryptoxanthin production by the isolated bacterial strain.