Fundamental understanding of Quararibea funebris flowers mucilage: an evaluation of chemical composition, rheological properties, and cytotoxic estimation

Ongoing research aims to identify innovative or underutilized biopolymers with valuable properties, such as thickeners, foaming agents, or emulsifiers, to enhance the functionality of foods, reduce toxicity, and lower processing costs in pharmaceutical preparations. Quararibea funebris , a Mexican plant used to prepare the pre-Hispanic drink "tejate", contains mucilage in its flowers, contributing to its fragrance and slight thickening effect. However, there is limited information on the characteristics and safety threshold of this mucilaginous material. This study investigated the chemical composition, rheological properties, and viability effects of Quararibea funebris flower mucilage. Gas chromatography-mass spectrometry analysis revealed its primary constituents: rhamnose, xylose, galactose, glucose, and galacturonic acid. Rheological testing indicated a concentration and temperature-dependent behavior, with the viscosity showing non-Newtonian shear-thinning characteristics in solutions with contents of 0.5–3.0 % (w/v). Dynamic mechanical analysis showed the evolution of dynamic moduli (G′ and G″) within the temperature range of 15–45 °C. At low concentrations (< 3.0 % w/v), the mucilage exhibited predominantly viscous behavior (G″), transitioning to a weak gel-like behavior with increasing concentration. Viability testing on Human embryonic kidney (HEK) 293 cells revealed concentration-dependent effects, with a safe concentration threshold at ≤ 0.63 mg/mL. However, mucilage treatment did not affect cell viability in human cervical cancer (HeLa) cells at 24 or 48 h. This study represents the first characterization of mucilage from flowers of Quararibea funebris , offering valuable insights for potential applications in biomedicine, pharmaceuticals, and the food industry. • Isolation for the first time of a mucilage in the genera Quararibea • The rheologyof the mucilage demonstrated a non-Newtonian viscous behavior • The rheology of this mucilage explains its function in the traditional beverage Tejate • The viability tests in HEK293 and HeLa cells showed promising safe outcomes