Abstract:

The contents and composition of soluble phenolic compounds in pear peel, core and flesh from 11 major cultivars
in northern China were determined and analyzed by high performance liquid chromatography (HPLC). Meanwhile, the
antioxidant activities of their ethanol extracts were evaluated by DPPH and hydroxyl scavenging radical assays. Results
indicated that: 1) the highest contents of soluble phenolic compounds were found in the core, followed by the peel and flesh; 2)
8 kinds of phenolic compounds, i.e., arbutin, gallic acid, catechinic acid, chlorogenic acid, caffeic acid, epicatechin, cumaric
acid and rutin were detected in both the core and peel, while 5 kinds of phenolic compounds, i.e., arbutin, gallic acid,
chlorogenic acid, caffeic acid and epicatechin were detected in the flesh; 3) chlorogenic acid, arbutin and epicatechin were
the major phenolic compounds in the peel and flesh with higher content of chlorogenic acid than arbutin in the flesh and the
opposite result for the peel. At the same time, the main phenolic constituents of the core were chlorogenic acid and arbutin
with higher level of the former when compared with the latter; 4) for each of the three fruit tissues, significant positive
correlations between phenolic compound contents and DPPH and hydroxyl radical scavenging activities were observed,
suggesting the close association of phenolic compounds with free radical scavenging activity.

Key words: pear, phenolic compounds, high performance liquid chromatography, antioxidant activity