Total Phenolic and Flavonoid Contents, Antioxidant and Anti-Inflammatory Activities of Different Solvent Fractions from the Ethanolic Extract of Allium ampeloprasum (“Sibujing”)

The spice Allium ampeloprasum, commonly known as “sibujing,” is a key ingredient in the "palapa" condiment, popular in Maranao dishes, and is traditionally used by the Maranao people in the Lanao regions of Mindanao, Philippines, to treat inflammatory diseases, fever, and cough. This study investigates the total phenolic content (TPC), total flavonoid content (TFC), and the antioxidant and anti-inflammatory activities of the crude ethanolic extract of A. ampeloprasum and its solvent fractions. TPC was determined using the Folin–Ciocalteu method, while TFC was assessed using the aluminum chloride colorimetric method. Anti-inflammatory activity and antioxidant activity were measured using the egg albumin denaturation assay and the DPPH radical scavenging assay, respectively. The results showed that the ethyl acetate fraction had the highest TPC (68.54 ± 1.44 mg GAE/g) and a moderately strong antioxidant capacity (EC₅₀ = 221.40 ± 2.97 μg/mL). On the other hand, the hexane fraction had the highest TFC (169.88 ± 0.64 mg QE/g) and showed promising anti-inflammatory activity (IC₅₀ = 205.83 ± 6.73 μg/mL). Interestingly, a very strong inverse correlation was observed between TPC and antioxidant EC₅₀, while a moderate inverse correlation was noted between the TFC and anti-inflammatory IC₅₀ of the plant’s extract and fractions. These correlations suggest that the phenolic and flavonoid compounds in the plant’s extract and fractions may significantly contribute to A. ampeloprasum’s antioxidant and anti-inflammatory effects. These findings support the traditional medicinal use of A. ampeloprasum for treating inflammatory diseases, highlight its natural antioxidant properties, and underscore its potential as a valuable source of bioactive compounds. This study recommends further research to identify the specific active compounds responsible for the observed biological activities.