Gutweed

Aka: Sea Lettuce (tubular form)

bright green tubular macroalgae (Chlorophyta, Ulvaceae) found in marine, brackish, and freshwater environments worldwide. previously classified as Enteromorpha intestinalis.

ethanol extract at 200 µg/mL showed a 35mm inhibition zone against Staphylococcus aureus, and methanolic extract inhibited biofilm formation by 91.26% at the same concentration.
most antibiotics kill planktonic bacteria but struggle against biofilms, which are protective bacterial communities that cause chronic infections, hospital-acquired infections, and antibiotic resistance.

43 compounds from U. intestinalis extract, which were docked against the SARS-CoV-2 S1 spike protein receptor binding domain. compounds including 2,4-di-tert-butylphenol, doconexent, and retinal showed the highest binding affinity, with pharmacokinetic validation confirming them as potential antiviral candidates that could inhibit viral spike protein.

oral administration of hydroalcoholic extract significantly reduced elevated urinary oxalate and reverted serum creatinine, uric acid, and BUN levels back to normal range in calcium oxalate urolithiasis rat models, suggesting regulatory action on endogenous oxalate synthesis and restoration of normal kidney physiology.

immune-stimulating effects in fish and mammals, antiviral properties against enveloped viruses, and as a biodegradable scaffold material for tissue engineering.

U. intestinalis is an efficient hyperaccumulator of nitrogen, phosphorus, and heavy metals from polluted water.