Bioengineered blue bacterial pigment for improved solubility and bioactivity

Overview

This research focuses on engineering a naturally occurring bacterial pigment to develop a soluble, non-toxic blue coloring agent suitable for beverage and consumer product applications. The team serendipitously discovered a deep blue pigment from a bacterial fermentation and identified minor oxygenated derivatives that maintain the rich blue color while offering improved solubility and reduced toxicity. By applying biosynthetic pathway engineering, the project aims to produce larger quantities of these enhanced derivatives, addressing the growing demand for natural blue colorants in food, beverage, and pharmaceutical industries where synthetic alternatives face increasing consumer and regulatory scrutiny.

Technical specifications

Key features:

• Naturally sourced blue pigment originally isolated from actinobacterial fermentation
• Oxygenated derivatives with enhanced water solubility (~1.3 mg/mL) and reduced toxicity compared to the parent compound
• Deep blue chromophore preserved across pH changes, with reversible color shift to purple-red under acidic conditions (pH = 3)
• Current production yield of approximately 30 mg/L from 15 L cultures, achieving >95% purity via liquid chromatography mass spectrometry and nuclear magnetic resonance
• Identified biosynthetic genes targeted for expression in faster-growing, more genetically tractable bacterial hosts
• Pathway manipulation strategy to preferentially produce oxygenated, more soluble pigment variants

Technology readiness level

This technology is currently at an early-to-mid stage of development. The team has successfully scaled up actinobacterial cultures and purified the blue pigment to high purity, demonstrating initial feasibility. However, biological screening has not yet been performed, and future validation will focus on rigorous toxicity assessment, long-term solubility testing, and pathway engineering to shift production toward the more desirable oxygenated derivatives. The transition to a faster-growing host organism is a key next step to improve production efficiency, as current yields require over two weeks of microbial growth. The technology holds promise for commercialization pending favorable biological safety profiles and successful biosynthetic pathway optimization.