Integrated Characterization of Wolffia globosa as a Potential Food Ingredient: Nutritional and Physicochemical Properties, Selected Elements, and Preliminary In Vitro Responses

Wolffia globosa (watermeal) is a potential plant-based food ingredient. This study characterized its nutritional and physicochemical properties, elemental levels, total phenolic content (TPC), total flavonoid content (TFC), DPPH radical-scavenging activity, IL-6 production in H2O2-stimulated RAW264.7 macrophages, and preliminary cell-viability responses. On a dry-weight basis, the tested W. globosa sample contained 25.83% protein, 4.56% fat, 16.58% ash, 8.80% crude fiber, and 44.22% carbohydrate. Arsenic and zinc were detected below their limits of quantification, whereas cadmium, copper, and lead were below their method detection limits. All analytical reporting limits were below the corresponding EFSA specification values. The extract had TPC and TFC values of 0.85 ± 0.03 mg GAE/g sample DW and 0.52 ± 0.02 mg QE/g sample DW, respectively, and showed weak DPPH radical-scavenging activity (IC50 = 7.58 ± 0.32 mg DW-equivalent/mL). At 0.1 mg DW-equivalent/mL, the H2O2-stimulated extract-treated group showed a lower IL-6 concentration than the H2O2-stimulated extract-free model control. Weak reductions in cancer-cell viability occurred only at high concentrations (IC50 values of approximately 38–42 mg DW-equivalent/mL). The biological findings remain preliminary. Overall, the tested sample showed promising nutritional and physicochemical characteristics, low selected-elements levels, and preliminary in vitro responses.