A FTIR Evident-Based Exploration of the Antioxidant Activity of Five Threatened Cactus Species

Abstract

Cacti, members of the botanical family Cactaceae, comprise approximately 127 genera and approximately 1,850 known species within the Caryophyllales order. Presently, various anthropogenic activities are causing the endangerment of several cactus species. Among the reasons cited for this threat, the aesthetic and medicinal values of cacti have garnered notable attention. This study aims to explore the medicinal potential, particularly in terms of antimicrobial, antioxidant, and phytochemical properties, of five threatened cactus species listed by the International Union for Conservation of Nature (IUCN) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES): Micranthocereus estevesii, Euphorbia lactea, Haageocereus crestata, Ferocactus acanthodes and Mammillaria huitzilopochtli. A Fourier-transform infrared (FTIR) analysis was conducted to substantiate and corroborate the findings. Notably, no prior studies have investigated the medicinal properties of these five species, underscoring the novelty of our research. Initially, specimens of the five cacti were collected from the Regional Plant Resource Center, Bhubaneswar, air-dried, and milled into powder. Phytoconstituents were then extracted individually using polar (water) and non-polar (methanol) solvents. The antimicrobial properties were assessed using agar well diffusion assays against Candida albicans, Escherichia coli and Staphylococcus aureus. Results indicated that methanol extracts of Micranthocereus estevesii and Euphorbia lactea inhibited Candida albicans, while aqueous extracts of Micranthocereus estevesii and Ferocactus acanthodes inhibited Escherichia coli and Staphylococcus aureus. Methanol extracts exhibited superior antioxidant activity compared to aqueous extracts. FTIR spectroscopy revealed distinctive peak values representing various functional groups in the extract components, including alcohols, carboxylic acids, phenols, aldehydes, alkanes, alkenes, ketones, aromatics, aliphatic amines, primary amines, ethers, alkyl halides, and esters. Both aqueous and methanolic extracts demonstrated promising antibacterial efficacy among the five cactus species studied, suggesting their potential application in pharmaceuticals and medication development. However, habitat degradation and illegal commerce pose significant threats to these species, emphasizing the urgent need for conservation efforts.