Abstract Detail

Phytochemical Section

Mahady , Gail B [1], Locklear, Tracie D [2], Patel, Udeshi [2], Adcock, Audrey F [1], Kroll, David [1].

Chemopreventative activities of extracts of Brassica oleracea (collard greens) from the Lumbee Tribe of North Carolina.

Brassica oleracea var. acephalaL. (Brassicaceae also known as Cruciferae) is the cultivar of B. oleracea known as "collard greens" or "collards" is a non-heading form of wild cabbage commonly eaten by populations in southern USA. "Collards" are a staple of Southern cuisine and are typically eaten year-around. Among the vegetable-containing plant families with proven anti-carcinogenic properties, the genus Brassica (cabbage family) has been determined to be effective at reducing the risk of cancer. Brassica oleracea var. acephala L. (collard greens) were collected in North Carolina and deposited in the Herbarium at Chapel Hill, NC. The leaves (5 kg) were dried, pulverized, and extracted in methanol (MeOH, extracted to exhaustion). The MeOH extract was defatted with dichloromethane (3 L) and partitioned intochloroform, ethyl acetate and butanol. The partitions were dried and tested at 20 mcg/ml in an MCF-7 ERE-SEAP reporter gene assay. The ethyl acetate partition (EtOAc) was the most active in the MCF-7cells assay and modified the expression of estrogen-dependent reporter genes. Both the methanol extract and the EtOAc partition inhibited the activity of HER-2 tyrosine kinase by 100% at a concentration of 20 mcg/ml. In addition, the EtOAc partition reduced the expression of the HER-2 receptor proteins in SK-Br breast cancer cells. In order to identify the chemical constituents responsible for this activity the EtOAc partition was fractionated using column chromatography (C18 reverse phase silica gel) using increasing concentrations of methanol/water as a solvent (10% MeOH to 100% MeOH), affording 5 fractions(10%, 30%, 50%, 70% and 100% methanol). The fractions were each analyzed byHPLC (Dionex), and the 70% fraction was found to be a single compound. Based on mass (m/z 309.1) and UV spectrometryand nuclear magnetic resonance (NMR) fraction 70 appears to be a known phenylpropanoid named hydroxycinnamoyl malate. This compound was previously identified in Brassica rapa.

Broader Impacts:

1 - North Carolina Central University, Durham, NC, 20772, USA
2 - University of Illinois at Chicago, Pharmacy Practice, 833 S Wood St, Chicago, IL, 60612, USA

Keywords:
chemoprevention
collard greens
ethnomedical.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Khorassan Ballroom/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 5:30 PM
Number: PPT002
Abstract ID:363