Valorizing Salicornia brachiata Seeds: A Rich Source of Polyphenols, Essential Fatty Acids, and Therapeutic Bioactivities.

Salicornia brachiata is an extreme halophyte that grows in saline marshes and produces seeds rich in phytochemicals and associated bioactivities. This study is aimed at comprehensively evaluating the phytochemical composition, fatty acid profile, and multifunctional bioactivities of S. brachiata seeds. Dried powdered S. brachiata seeds were subjected to sequential extraction using hexane (HE), dichloromethane (DE), and methanol (ME) in order. The fatty acid profile of HE was analyzed using GC-MS. Total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), and antioxidant activity of each extract were determined. Enzyme inhibitory potential was evaluated against α-amylase, α-glucosidase, lipase, angiotensin-converting enzyme, and urease. Anti-inflammatory activity and antibacterial activity were assessed for S. brachiata seed powder extracts. The results revealed that ME has the highest quantities of TPC, TFC, and CTC. GC-MS analysis of HE revealed linoleic acid (53.32%) as the dominant fatty acid, with an unsaturated-to-saturated ratio of 2.36:1, indicating strong nutritional and bioactive potential. ME showed the lowest IC50 for DPPH and ABTS radical scavenging assays: 32.13 ± 0.97 and 75.11 ± 2.17  μg/mL, respectively. HE expressed a potent inhibition for antidiabetic activity compared to acarbose. The lowest IC50 for lipase inhibition among extracts was shown by ME (241.67 ± 24.91  μg/mL). DE showed strong antihypertensive activity (78.78% ± 1.08%) at 0.5 mg/mL, though less effective than captopril (91.85% ± 1.23%). HE and DE expressed lower IC50 values: 32.40 ± 2.21 and 12.43 ± 1.31  μg/mL, respectively, in the urease inhibitory assay, highlighting their higher potency compared to thiourea with an IC50 value of 72.23 ± 3.76  μg/mL. DE and ME showed less potency than aspirin in the anti-inflammatory assay. Antibacterial efficacy of S. brachiata seed powder extracts demonstrated a broad spectrum of defense against tested bacteria. Therefore, S. brachiata seeds exhibit multifunctional bioactivities, making them an ideal supplement for fortified foods as well as an effective nutraceutical.