Prodigiosin As N-heterocyclic compound: Production optimization, bioactivity evaluation, and in-silico docking against key enzymes related to inflammation, obesity, diabetes, and the insulin signaling pathway

Diabetes is known to cause severe pancreatic inflammation and reduce insulin levels, leading us to investigate the effects of prodigiosin (PG), a red, heterocyclic bacterial compound extracted from Serratia marcescens. The physicochemical and nutritional conditions, along with the extraction solvents for PG, have been optimized for efficient production. PG was produced through bacterial culture, purified by high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC), characterized by Fourier-transform infrared spectroscopy (FTIR) and ultraviolet (UV) spectroscopy. In vitro, PG effectively inhibited key inflammatory enzymes, such as phospholipase A2 (PLA2) and elastase (ELA), in a dose-dependent manner, achieving maximum inhibition rates of 85.3 and 91.4 % at concentrations of 320 µg/mL, with IC₅₀ values of 63 µg/mL and 54.7 µg/mL, respectively. PG also exhibited a maximum inhibition of 82.4 % for myeloperoxidase (MPO) at a concentration of 160 µg/mL, with an IC₅₀ value of 25.9 µg/mL. This indicates that PG is a good candidate for treating these two metabolic diseases. Moreover, PG shows a significant ability to activate insulin signaling through its capacity to stimulate protein tyrosine phosphatase 1B (PTP1B) and inhibit dipeptidyl peptidase-4 (DPP-4), with IC₅₀ values of 67 and 28 µg/mL, respectively, compared to the specific inhibitors CLM and STG (with IC₅₀ values of 19 and 27 µg/mL, respectively). These powerful affinities, stability, and the durability of PG inhibition of these enzymes are confirmed by the determination of binding energy, ligand efficiency, and estimated inhibition constant (Ki). Conclusion: PG benefits from sustainable, cost-effective biological production and exhibits potent anti-inflammatory, antioxidant, and anti-diabetic properties, positioning it as a promising candidate for pharmaceutical and food applications.