Characterizing Eckol as a Therapeutic Aid: A Systematic Review

Manandhar, Bandana; Paudel, Pradeep; Seong, Su Hui; Jung, Hyun Ah; Choi, Jae Sue

Among the various potential targets for treating obesity in humans, pancreatic lipase holds great potential. Pancreatic lipase is involved in the absorption of triglycerides by the small intestine which eventually gets secreted by the pancreas. It is responsible for the hydrolysis of triglycerides into glycerol and fatty acids [130] . An investigation of a methanolic extract of E. bicyclis revealed significant inhibition on pancreatic lipase through porcine pancreatic lipase assay (IC 50 value 36.4 ± 2.9 mg/mL) leading to the isolation of eckol, fucofuroeckol A, 7-phloroeckol, dioxinodehydroeckol, phlorofucofuroeckol-A, and dieckol. Since eckol lacks ether linkage at the C-7 position of its phlorotannin skeleton, it exhibited much weaker activity against pancreatic lipase than fucofuroeckol A and 7-phloroeckol, having one phloroglucinol element in the same position. Also, the molecular weight difference between the compounds had no impact on their pancreatic lipase inhibitory activity. The existence of a phloroglucinol moiety in eckol structure at the C-7 position and the number of hydroxyl groups in eckol, fucofuroeckol A, and 7-phloroeckol might have positively influenced the inhibition of pancreatic lipase, probably through their unique receptor binding [79] .