A research article published in Advances in Pharmacological and Pharmaceutical Sciences demonstrates the strong antibacterial and antioxidant activities of a leafy cactus commonly used in traditional medicine.
Pereskia bleo is a well known medicinal plant native to South America. It is cultivated across Asia and used to treat medical issues ranging from hypertension to diabetes, cancer and skin wounds. However, few studies have been carried out to investigate its phytochemical and biological activities.
The team from Universiti Teknologi MARA in Malaysia used the Folin–Ciocalteu test and a free radical DPPH scavenging assay on P. bleo extract in different solvents to evaluate the total phenolic content and antioxidant activity of Pereskia bleo respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays were then carried out to test antibacterial activity against the Gram-positive bacteria Streptococcus pyogenes and Staphylococcus aureus and the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa.
The Folin–Ciocalteu test showed that P. bleo extract in methanolic extract had the highest total phenolic content compared to the chloroform and hexane extracts. The methanolic extract was therefore expected to exhibit higher antioxidant activity, which was confirmed by the DPPH assay. In the MIC and MBC assays, the methanolic and chloroform extracts both demonstrated strong activity against all four bacteria, but the hexane extract showed weak antibacterial activity.
The four bacteria included in this study are all related to food spoilage and food-borne diseases, therefore this study suggests that certain P. bleo extracts could be used as a natural preservative in food.
This blog post is distributed under the Creative Commons Attribution License (CC-BY). Illustration by David Jury.