Optimal fermentation medium and extraction conditions for lycopene production by Polymorphospora sp. A560

Lycopene, a vital antioxidant, can reduce oxidative damage to cells caused by reactive oxygen, prevent cancer, lower blood cholesterol levels, and mitigate cardiovascular diseases. We screened a lycopene-producing strain of genus Polymorphospora, designated A560, and discovered that its metabolic pathway lacks the cyclooxygenase gene cytY, which is responsible for converting lycopene into γ-carotenoids. The absence of cytY alleviates the challenges associated with the addition of a cyclooxygenase inhibitor, which previously hindered the large-scale accumulation of lycopene in Blakeslea trispora. This study implemented a multi-stage optimization strategy: adjusting the solvent system (acetone/n-hexane/ethanol) and extraction temperature and duration to optimize extraction conditions and enhance recovery rates. Using a uniform design (UD), lycopene yield was maximized by adjusting medium components. Under hexane/ethanol (v/v=2:1) extraction and 60 °C water bath treatment for 1h, lycopene yield increased by 37.13% (from 45.25 to 62.05 mg/L) compared to acetone extraction at room temperature. Following optimized cultivation conditions, lycopene yield increased by 224.64% (from 62.05 to 201.44 mg/L), establishing a novel microbial resource for fermentative lycopene production.