Cho, Suengmok Yang, Hyejin Jeon, You-Jin Lee, C. Justin Jin, Young-Ho Baek, Nam-In Kim, Dongsoo Kang, Sung-Myung Yoon, Minseok Yong, Heim Shimizu, Makoto Han, Daeseok 2024-01-20T14:33:00Z 2024-01-20T14:33:00Z 2021-09-05 2012-06-01 0308-8146 https://pubs.kist.re.kr/handle/201004/129156 The primary objective was to investigate whether seaweeds have hypnotic activity. Methanol extracts of 30 seaweeds were screened for their binding activity at the GABA type A-benzodiazepine (GABA(A)-BZD) receptor, a well-characterised molecular target for sedative-hypnotics. The most active seaweed was Ecklonia cava Kjellman (ECK). An ethanol extract of ECK (ECK-E) significantly potentiated pentobarbital-induced sleep in mice. In four solvent fractions separated from ECK-E, hypnotic activity was proportional to contents of total phenols and total phlorotannins, known as seaweed polyphenols. Major phlorotannins of the ethyl acetate (EtOAc) fraction with the highest activity were eckol, eckstolonol, dieckol, and triphlorethol-A, and their K, (binding affinity, mu M) values for [H-3]-flumazenil binding were 1.070, 1.491, 3.072, and 4.419, respectively. Hypnotic effects of ECK-E and the EtOAc fraction were fully inhibited by flumazenil, a specific GABA(A)-BZD receptor antagonist. These results imply that phlorotannins of ECK induce sleep by positive allosteric modulation of the GABA(A)-BZD receptor. 2011 Published by Elsevier Ltd. English ELSEVIER SCI LTD BINDING ASSAYS IN-VITRO ANTIOXIDANT LIGAND GABA(A) ALGA PHLOROFUCOFUROECKOL IDENTIFICATION FLAVONOIDS DIECKOL Phlorotannins of the edible brown seaweed Ecklonia cava Kjellman induce sleep via positive allosteric modulation of gamma-aminobutyric acid type A-benzodiazepine receptor: A novel neurological activity of seaweed polyphenols Article 10.1016/j.foodchem.2011.08.040 1 FOOD CHEMISTRY, v.132, no.3, pp.1133 - 1142 FOOD CHEMISTRY 132 3 1133 1142 scie scopus 000301022400003 2-s2.0-84862798191 Chemistry, Applied Food Science & Technology Nutrition & Dietetics Chemistry Food Science & Technology Nutrition & Dietetics Article BINDING ASSAYS IN-VITRO ANTIOXIDANT LIGAND GABA(A) ALGA PHLOROFUCOFUROECKOL IDENTIFICATION FLAVONOIDS DIECKOL Edible seaweeds Ecklonia cava Kjellman Phlorotannin GABA type A-benzodiazepine receptor Hypnotic activity