Nutritional profiling, phytochemical screening, cytotoxicity, and antioxidant content analysis for different crude extracts of Ulva lactuca from coast of Bangladesh

This current investigation assessed the proximate composition, mineral contents, phytochemicals, cytotoxicity and antioxidant activity of Ulva lactuca (UL). Five crude extracts of UL like 100% water (CE1), 50% water+50% ethanol (CE2), 50% water+50% methanol (CE3), 100% ethanol (CE4) and 100% methanol (CE5) were used to screen out the cytotoxicity, phytochemicals and antioxidant activity. DPPH, ABTS, phosphomolybdenum, reducing power, and nitric oxide scavenging activity was determined by in-vitro methods. Cytotoxicity of extracts was assayed using brine shrimp. Results indicated that powder of UL contains a comparable amount of proximate and mineral content. Phytochemical screening, Fourier transform infrared (FT-IR) and High-performance liquid chromatography (HPLC) analysis confirmed the presence of different secondary metabolites, functional groups and polyphenols. The CE1 showed highest phenolic content at 51.87 mg of GA/g and flavonoid content at 49.18 mg of quercetin/g, followed by CE2, CE3, CE4 and CE5. Regarding antioxidants, CE1 exhibited the highest antioxidant activity as evaluated by DPPH (75.62%), ABTS (57.67%), Phosphomolybdenum (124.58 mg of AAE/g), Reducing power (52.34 mg AAE/g), and NO scavenging (41.87%) assays. Cytotoxicity was found to be present in a dose-dependent manner. These results indicated that dried powder and extracts of UL contain macro-micro nutrients, and diversified phytochemicals with potential antioxidant activity.