(P04-041-24) Evaluation of a Polyphenolic, Betalain-Rich Extract From Bougainvillea glabra, as a Potential Nutraceutical Additive

Objectives: Bougainvillea glabra is a widely cultivated ornamental species in Latin America, however, its application as a functional ingredient remains unexplored. The primary objective was to evaluate the biological and technological potential of an extract obtained from the bracts of an unexplored source of natural pigment such as Bougainvillea glabra with abundant bioactive compounds.

Methods: B. glabra pigments (BGE) were extracted using solid-liquid ultrasound-assisted extraction. Total betalain and polyphenol content were performed using a spectrophotometric method. DPPH and ABTS radical scavenging were determined through spectrophotometric approaches using Trolox as control and BGE concentrations ranging from 0.25 - 5 mg/mL. α-amylase enzymatic inhibitory activity was determined using the pure enzyme and soluble starch as substrate and BGE concentrations from 0.25 - 5 mg/mL. The antibacterial potential was assessed on Escherichia coli, Staphylococcus aureus, Streptococcus mutans, and Pseudomonas aeruginosa by a microplate method where the bacterial growth was explored considering the inoculum’s optical density treated with BGE concentrations (1-15 mg/mL). Cytotoxicity on RAW264.7 macrophages was assessed by an MTS-based commercial kit and BGE treatments (0.25-1 mg/mL).

Results: Total betalain content in BGE was 0.6 mg/mL, while the total polyphenol content was 0.1 mg/mL eq. of gallic acid. BGE scavenged ABTS radical with inhibition (p < 0.05) values ranging from 149-180 µM Trolox equivalents, an α-amylase test inhibition revealed a 27.9 % inhibition (p < 0.05) by BGE at 5 mg/mL, while the pharmacological control inhibited (p < 0.05) 76.1% at 1 mM. Studying the potential reduction growth with BGE treatment, no statistical difference (p > 0.05) was found in the optical density after 24 h. On the other hand, up to 1 mg/mL of BGE, no cytotoxicity major to 10% was found in RAW264.7 macrophages.

Conclusions: B. glabra is a promising source of natural pigments with radical scavenging and α-amylase inhibitory potential. Future experiments will allow us to determine biological and technological applications of an unexplored extract from a widely cultivated species in Latin America.

Funding Sources: Presenting author is supported by a scholarship from CONAHCYT, Mexico. This project is financed by the Institute for Obesity Research, Tecnológico de Monterrey.