Open AccessCharacterization of γ‐glutamyltranspeptidases from dormant garlic and onion bulbs
Author(s) -
Sun Yuee,
Hu Jing,
Wang Weidong,
Zhang Bin,
Shen Yingbin
Publication year - 2019
Publication title -
food science and nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.614
H-Index - 27
ISSN - 2048-7177
DOI - 10.1002/fsn3.820
Subject(s) - allium , allium sativum , proline , chemistry , food science , aspartic acid , liliaceae , biochemistry , amino acid , botany , biology
This study investigated the characteristics of γ‐glutamyltranspeptidases ( GGT s) isolated from dormant garlic ( Allium sativum L.) and onion ( Allium cepa L. var. agrogatum Don ) bulbs. GGT s were isolated using ( NH 4 ) 2 SO 4 precipitation and hydrophobic interaction chromatography (phenyl‐Sepharose column). The optimal temperature, optimal pH of extraction, and the effects of metal ions and organic compounds on the activity of GGT s were investigated. The optimal pH of the GGT s of garlic and onion was 5 and 7, respectively; the optimal temperatures were 70 and 50°C, respectively. Garlic's GGT had a major band at 53 kDa, whereas onion's GGT had two bands at 55 and 22 kDa. Cu 2+ , Mn 2+ , Fe 2+ , Mg 2+ , glucose, aspartic acid, and cysteine significantly enhanced the activity of garlic's GGT . Lysine and proline remarkably promoted the activity of onion's GGT , whereas Cu 2+ , glucose, and aspartic acid repress its activity. These results may deepen our understanding of allium GGT s and promote the commercial production of bioactive allium compounds.