Assessment of glucosinolates, antioxidative and antiproliferative activity of broccoli and collard extracts

摘要

Natural compounds isolated from vegetables have protective and disease-preventing potential for the development of functional food. This study investigates the in vitro antioxidant capacity, total polyphenol and total flavonoid content, glucosinolate and glucosinolate degradation products of broccoli and collard extracts. In vitro antitumor activities on two human tumour cell lines (MCF-7 and HeLa) were studied. Broccoli and collard extracts were extracted from fresh, blanched and boiled broccoli florets and collard leaves. The Oxygen Radical Absorbance Capacity (ORAC) assay revealed that collard extracts exhibited higher antioxidant capacity than broccoli extracts. Total polyphenol and total flavonoid contents were also higher in collard extracts. The extracts were compared for the contents of total glucosinolates, indol glucosinolates and aliphatic glucosinolates. Glucoraphanin was the predominant compound in total glucosinolate content, followed by glucobrassicin and neoglucobrassicin (95.97 mu,mol 100 g(-1) fresh weight (fw), 85.42 mu.mol 100g(-1) fw and 82.12 mu..mol 100g(-1) fw, respectively) in broccoli extracts; while in collard extracts, the major glucosinolate was glucobrassicin (80.33 mu.mol 104-1 fw), followed by glucoiberin (67.50) junol 100 g(-1) fw and sinigrin (21.91 pAnol 100 g(-1) fw). The strongest antiproliferative effect was observed in extracts obtained by blanching. The present study established that the extracts that were examined possess antioxidant and promising antitumour activities. (C) 2017 Elsevier Inc. All rights reserved.