title: Antineurodegenerative effect of phenolic extracts and caffeic acid derivatives in romaine lettuce on neuron-like PC-12 cells.
abstract: In recent decades, romaine lettuce has been one of the fastest growing vegetables with respect to its consumption and production. An understanding is needed of the effect of major phenolic phytochemicals from romaine lettuce on biological protection for neuron-like PC-12 cells. Phenolics in fresh romaine lettuce were extracted, and then its total phenolics and total antioxidant capacity were measured spectrophotometrically. Neuroprotective effects of phenolic extract of romaine lettuce and its pure caffeic acid derivatives (caffeic, chicoric, chlorogenic, and isochlorogenic acids) in PC-12 cells were evaluated using two different in vitro methods: lactate dehydrogenase release and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assays. Total phenolics and total antioxidant capacity of 100 g of fresh romaine lettuce averaged 22.7 mg of gallic acid equivalents and 31.0 mg of vitamin C equivalents, respectively. The phenolic extract of romaine lettuce protected PC-12 cells against oxidative stress caused by H(2)O(2) in a dose-dependent manner. Isochlorogenic acid, one of the phenolics in romaine lettuce, showed stronger neuroprotection than the other three caffeic acid derivatives also found in the lettuce. Although romaine lettuce had lower levels of phenolics and antioxidant capacity compared to other common vegetables, its contribution to total antioxidant capacity and antineurodegenerative effect in human diets would be higher because of higher amounts of its daily per capita consumption compared to other common vegetables.
authors.affiliation: Department of Food Science and Technology and Institute of Life Science and Resources, Kyung Hee University, Yongin, Republic of Korea.
authors.forename: Sung-Eun
authors.initials: SE
authors.lastname: Im
authors.forename: Hyungeun
authors.initials: H
authors.lastname: Yoon
authors.forename: Tae-Gyu
authors.initials: TG
authors.lastname: Nam
authors.forename: Ho Jin
authors.initials: HJ
authors.lastname: Heo
authors.forename: Chang Yong
authors.initials: CY
authors.lastname: Lee
authors.forename: Dae-Ok
authors.initials: DO
authors.lastname: Kim
mesh_terms: D000818:Animals; D002109:Caffeic Acids / Q000494:pharmacology*; D005998:Glycine / Q000031:analogs & derivatives; D018545:Lactuca / Q000737:chemistry*; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects; D010636:Phenols / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats
chemical_list: D002109:Caffeic Acids; D018696:Neuroprotective Agents; D010636:Phenols; D010936:Plant Extracts; C084257:PC 12 ester; D005998:Glycine; C040048:caffeic acid