Comparison of the antioxidant and antimicrobial properties and microbial quality of cold pressed cactus pear seed oil with commercially available fruit and vegetable oils

Abstract

This study aimed to investigate optimum levels of the antioxidants, and antimicrobials, of cactus pear seed oils (Opuntia ficus-indica and Opuntia robusta) and compare them with those of other cold-pressed functional plant oils already on the market (argan, canola, marula, sunflower, sesame, extra virgin olive oils). Besides antioxidant activities, cactus pear seed oil has been reported to contain bioactive molecules with antimicrobial activities. The amount of tocopherol in each oil sample was measured using high performance liquid chromatography (HPLC). Opuntia robusta had the second-highest total tocopherol content after soybean oil, with both having high β + γ tocopherol isomer contents. Microbial quality tests were performed by using total bacterial count (TBC), coliform counts, E. coli, S. aureus and mould and yeast counts. For microbial quality, marula and sunflower oils showed the presence of mould. Opuntia ficus-indica was the second most effective against E. coli and S. aureus and was solely effective against P. aeruginosa among the oil samples. These findings could be a way for setting standards and policies that would assist producers and entrepreneurs in detecting any illegal adulteration with foreign matter and ensuring the oil remains in its high premium quality state. This would save entrepreneurs from fines, consumer complaints, potential brand damage, or unwanted organoleptic effects during product development.