Comparison of Antioxidant and Anti Enteritis Activities of Ethanolic Extracts of Different Varieties of Camellia oleifera Seeds

To investigate the differences in antioxidant and anti-enteritis activities among Camellia oleifera varieties, fifteen samples from five varieties (Camellia vietnamensis Huang., Camellia chekiangoleosa Hu., Camellia yuhsienensis Hu., Camellia meiocarpa Hu. and Camellia oleifera Abel.) were collected as research subjects. The anti-enteritis activity of camellia ethanol extract (CET) was evaluated using the Drosophila "Blue Spirit" model. The total phenolic content of the 15 samples was measured, along with CET’s inhibitory activity against lipoxygenase (LOX) and cyclooxygenase-2 (COX-2), and free radical scavenging activity. The results demonstrated that the total phenolic content across all 15 Camellia oleifera seed samples was measured at 21.50~32.41 mg/g. Camellia oleifera ethanol extract (CET) from all varieties was found to exhibit significant inhibitory effects on LOX, COX-2, and Drosophila enteritis, with the highest average inhibition rates against LOX (84.78%) and Drosophila enteritis (83.76%) observed in Camellia oleifera Abel. CET, while optimal COX-2 inhibition (72.36%) was achieved by Camellia yuhsienensis Hu. CET. Additionally, the scavenging rate of DPPH radicals, ABTS⁺ radicals and superoxide anion radicals by CET of all varieties of Camellia oleifera was higher than 66%, with the highest scavenging rate of ABTS⁺ radicals by Camellia yuhsienensis Hu. (77.62%), the highest clearing rate of superoxide anion by Camellia chekiangoleosa Hu. (93.64%), and the highest scavenging rate of DPPH radicals by Camellia vietnamensis Huang. (79.70%). There was a significant positive correlation between LOX inhibition and Drosophila enteritis relief (r=0.65, P<0.01). In summary, all 15 Camellia oleifera seed samples had free radical scavenging activity, with significant differences among different Camellia oleifera varieties. Inhibition of LOX is the key mechanism of Camellia oleifera CET against enteritis.