Antimicrobial and Antioxidant Activity of Some Plant Extracts against Different Food Spoilage and Pathogenic Microbes

Aims: Guava (Psidium guajava), pomegranate (Punica granatum), olive (Olea europaea L.), and moringa (Moringa oleifera( extracts which are assumed to contain active components and which are renewable sources in fighting infections of microbes. This study aimed to investigate its antioxidant and antimicrobial activity.

Methodology: The agar well diffusion technique, minimum inhibitory concentration (MIC), total phenolic content (TPC), total flavonoid content (TFC), and the free radical scavenging activity of the plant extracts were applied.

Results: All extracts exhibited different results against the microorganism used in the research. The minimum inhibitory concentration (MIC) values for bacteria and fungi ranged from 25 to 300 mg/mL. The antioxidant activity was evaluated by using DPPH radical scavenging assay. In addition, the amount of total phenolic content (TPC) of the extracts ranged from 48.08 to 324.08 mg/g, while total flavonoid content (TFC) ranged from11.53 to 65.85 mg/g.

Conclusion: It could be noticed that the guava and pomegranate extracts had strong antioxidant and antimicrobial effects, while olive extract had a moderate effect, but moringa showed a very weak effect against tested microbes. Therefore, the herbal extracts of guava and pomegranate could be used as novel, safe, and effective food preservatives instead of chemical ones.