Recovery of roseoflavin from a recombinant Streptomyces davaonensis strain by using biphasic aqueous systems

Abstract

BACKGROUND Roseoflavin (RoS) is a naturally occurring red color riboflavin analog compound, produced mainly by Streptomyces davaonensis, with a rising profile owing to its antibacterial potential. However, there is a lack of strategies for its downstream processing and the existing ones are limited to chromatographic techniques involving harmful reagents. The use of aqueous two‐phase systems (ATPS), a liquid–liquid extraction method, is explored in this work as an alternative strategy to recover and purify RoS from S. davaonensis cultures. RESULTS Polymer‐phosphate, alcohol‐phosphate and ionic liquid (IL)‐phosphate systems that varied in composition were tested, where polyethylene glycol (PEG), ethanol (EtOH) and 1‐ethyl‐3‐methylimidazolium acetate ([C2mim] [OAC]) represent the top phases, and phosphate the bottom phase. The partition behavior of either RoS alone or with contaminants was evaluated. In both cases, RoS showed a preference for top phase in all the systems tested. When cell‐free cultures were added to the systems, IL‐salt (13% and 30% w/w), EtOH‐phosphate [50% tie‐line length (TLL)] and PEG8000‐phosphate (35% w/w TLL) systems presented the highest RoS recovery (>95%), but separation of RoS and contaminants was not accomplished. The systems that demonstrated separation of RoS and contaminants were the PEG3350‐ and PEG8000‐salt systems, both with a 15% w/w TLL, as RoS and contaminants partitioned to top and bottom phases, respectively. CONCLUSION This is the first attempt at using ATPS to recover RoS from S. davaonensis cultures. It has been proven that RoS can be recovered directly from S. davaonensis cultures using biphasic systems. This strategy may represent a greener alternative to chromatographic techniques. © 2021 Society of Chemical Industry (SCI).

Aqueous Two-Phase Systems Based on Ionic Liquids and Deep Eutectic Solvents as a Tool for the Recovery of Non-Protein Bioactive Compounds—A Review

“…Several metabolites of industrial interest (e.g., proteins, enzymes, carbohydrates, lipids, pigments, phenolic compounds, and chemicals, among others) [59][60][61][62][63] can be produced by the most diverse microorganisms, including wild strains [64], genetically modified strains [65], or microbial consortium [63]. The recovery of target biocompounds will depend on their intrinsic characteristics, the place where they are produced (inside the cell or in the extracellular medium), the type of cultivation (solid or submerged state), and the culture medium (synthetic or containing industrial byproducts).…”

Mechanistic Insights into Roseoflavin Synthesis by N,N-8-Demethyl-8-aminoriboflavin Dimethyltransferase (RosA): Molecular Dynamics Simulations and Residue Conservation Analysis

“…Although RoF is commercially available via a chemically synthesized approach, the method still provides low yield (∼5% of molar yield) and can be quite expensive. Bacterial fermentation or a biocatalytic process is much greener and produces a higher yield of RoF than the chemical method . Recently, metabolic engineering was used to increase the expression of the essential enzymes for RoF production .…”

“…Bacterial fermentation or a biocatalytic process is much greener and produces a higher yield of RoF than the chemical method. 14 Recently, metabolic engineering was used to increase the expression of the essential enzymes for RoF production. 15 However, production of RoF by a whole cell may also produce undesirable by-products; thus, purification steps are required.…”