Assessing the Antioxidant Activity and Anti-inflammatory Potency on Lipopolysaccharide-induced RAW 264.7 Macrophages of Eleven Methanolic Extracts Indigenous Vegetables

Abstract

Indigenous vegetables have long been part of the traditional diet in southern Thailand, often paired with spicy foods. This study aimed to explore the total phenolic and flavonoid contents of eleven commonly consumed indigenous vegetables in Nakhon Si Thammarat province, while also evaluating their antioxidant and anti-inflammatory properties through methanolic crude extracts. The findings revealed that Litsea petiolate (LP) contained the highest amount of flavonoids, with 270.90 ± 6.175 mg QE/g extract, whereas Anacardium occidentale (AO) showed the greatest phenolic content at 160.40 ± 1.32 mg GAE/g extract. In terms of antioxidant properties, Glochidion wallichianum (GW) demonstrated significant activity through the FRAP assay, yielding 484.08 ± 10.010 μmole TE/g extract and 4,115.36 ± 100.00 μmole Fe²⁺/g extract. Meanwhile, AO exhibited the most substantial results in the DPPH assay, with an 85.99 ± 0.762 mg/ml capacity. The IC₅₀ values of AO (7.39 ± 0.176 mg/ml) and GW (7.70 ± 0.820 mg/ml) surpassed that of ascorbic acid, indicating their high antioxidant potential. In terms of anti-inflammatory effects, Crassocephalum crepidioides (CC) effectively inhibited nitric oxide production at different concentrations, while the LP extract impacted the viability of the RAW264.7 cell line, a distinction not observed in the other vegetables studied. These results underscore the significant bioactive potential of these indigenous vegetables. This not only enhances their value in sustainable food systems but also highlights their educational importance in promoting knowledge of the plant cycle for future generations