Research Article Antioxidative Effects and Inhibition of Human Low Density Lipoprotein Oxidation In Vitro of Polyphenolic Compounds in Flammulina velutipes (Golden Needle Mushroom) Mohammad Azizur Rahman, 1,2 Noorlidah Abdullah, 1 and Norhaniza Aminudin 1 1 Mushroom Research Centre, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia 2 Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1340, Bangladesh Correspondence should be addressed to Noorlidah Abdullah; noorlidah@um.edu.my Received 26 September 2014; Accepted 5 January 2015 Academic Editor: Dragan Milenkovic Copyright © 2015 Mohammad Azizur Rahman et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Dietary polyphenolic compounds mediate polynomial actions in guarding against multiple diseases. Atherosclerosis is an oxidative stress driven pathophysiological complication where free radical induced oxidative modifcation of low density lipoprotein (LDL) plays the ground breaking role. Mushrooms have been highly regarded for possessing an antioxidant arsenal. Polyphenolic compounds present in dietary mushrooms seem pertinent in withstanding LDL oxidation en route to controlling atherosclerosis. In this study, the antioxidative efect of fve solvent fractions consisting of methanol : dichloromethane (M : DCM), hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), and aqueous residue (AQ) of Flammulina velutipes was evaluated. M : DCM fraction showed the most potent 2,2-diphenyl-1-picrylhydrazyl radical scavenging efect with IC 50 of 0.86 mg/mL and total phenolic content of 56.36 gallic acid equivalent/g fraction. In LDL oxidation inhibitory tests, M : DCM fraction at 1 g/mL concentration mostly lengthened the lag time (125mins) of conjugated diene formation and inhibited the formation of thiobarbituric acid reactive substances (48.71%, at 1 mg/mL concentration). LC-MS/MS analyses of M : DCM fraction identifed the presence of polyphenolic substances protocatechuic acid, p-coumaric, and ellagic acid. Tese chain-breaking polyphenolics might impart the antioxidative efects of F. velutipes. Tus, mushroom-based dietary polyphenolic compounds might be implicated in slowing down the progression of atherosclerosis. 1. Introduction Te implication of dietary polyphenols and their efects upon cell biochemistry and pathophysiology emanates from their prophylactic role against multiple diseases. Polyphe- nols entail a diverse array of plant and fungal secondary metabolites having pluripotent actions at the cellular level [1]. Teir mode of action is as diverse as their structures are and both ameliorating and null efects have been noticed while considering antioxidative role of dietary polyphenols [2, 3]. Substantial evidences support their involvement in cellular signaling processes that ultimately result in reduced produc- tion of infammatory mediators and increased generation of vasodilators [4, 5]. Although no direct antioxidative function of dietary polyphenols has been noticed in human cardio- vascular health studies, polyphenols have been implicated in inducing antioxidant defense by stimulating the Nrf2/Keap1 signaling pathway [6, 7]. Actually, free radicals are being constantly produced in our body as byproducts or defensive weapons against pathogens and also removed accordingly with a view to maintaining normal cellular biochemistry and physiology [8, 9]. However, the imbroglio of their excessive produc- tion and accumulation aficts the cellular and physiologi- cal normalcy resulting in pathophysiological consequences [10]. Atherosclerosis being such a free radical-induced and Hindawi Publishing Corporation Oxidative Medicine and Cellular Longevity Volume 2015, Article ID 403023, 10 pages http://dx.doi.org/10.1155/2015/403023