Antibacterial and antioxidant activity of Black, Red, and Chinese cultivars of Raphanus sativus

Our study sought to ascertain the biological activities of three distinct radish cultivars: Black, Red, and Chinese. The materials were subjected to lyophilisation for 72 hours, after which ethanolic extracts were obtained via the Soxhlet method. The antioxidant activity of the ethanolic extracts was assessed using the DPPH scavenging assay and the ferric reducing assay. At the same time, the total phenolic content was quantified by the Folin-Ciocalteu method. The antibacterial efficacy of the extracts against the test bacteria was assessed via the disc diffusion method. The findings revealed that Chinese radish exhibited the highest phenolic concentration, quantified at 18.1 mg GAE/g. The DPPH scavenging assay results indicated that, concerning the total phenolic content, the maximum scavenging activity was seen in Chinese radish at 72%. Subsequently, black radish exhibited a DPPH scavenging rate of 59%, while red radish demonstrated a rate of 39%. The ferric reducing power results corroborated the DPPH scavenging assay, indicating the activity hierarchy as Chinese radish, black radish, and red radish, respectively. Antibacterial activity of the ethanolic extracts obtained was also examined; according to the results, only the black radish extract showed antibacterial action against Enterococcus faecalis (13.5 mm) and Staphylococcus aureus (11 mm). This study revealed the effects of different radish cultivars on antioxidant and antibacterial activity.