| Environmental stresses induce health-promoting phytochemicals in lettuce. | |
| | |
MedLine Citation:
|
PMID: 19297184 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Plants typically respond to environmental stresses by inducing antioxidants as a defense mechanism. As a number of these are also phytochemicals with health-promoting qualities in the human diet, we have used mild environmental stresses to enhance the phytochemical content of lettuce, a common leafy vegetable. Five-week-old lettuce (Lactuca sativa L.) plants grown in growth chambers were exposed to mild stresses such as heat shock (40 degrees C for 10 min), chilling (4 degrees C for 1d) or high light intensity (800 micromolm(-2)s(-1) for 1d). In response to these stresses, there was a two to threefold increase in the total phenolic content and a significant increase in the antioxidant capacity. The concentrations of two major phenolic compounds in lettuce, chicoric acid and chlorogenic acid, increased significantly in response to all the stresses. Quercetin-3-O-glucoside and luteolin-7-O-glucoside were not detected in the control plants, but showed marked accumulations following the stress treatments. The results suggest that certain phenolic compounds can be induced in lettuce by environmental stresses. Of all the stress treatments, high light produced the greatest accumulation of phenolic compounds, especially following the stress treatments during the recovery. In addition, key genes such as phenylalanine ammonia-lyase (PAL), l-galactose dehydrogenase (l-GalDH), and gamma-tocopherol methyltransferase (gamma-TMT) involved in the biosynthesis of phenolic compounds, ascorbic acid, and alpha-tocopherol, respectively, were rapidly activated by chilling stress while heat shock and high light did not appear to have an effect on the expression of PAL and gamma-TMT. However, l-GalDH was consistently activated in response to all the stresses. The results also show that these mild environmental stresses had no adverse effects on the overall growth of lettuce, suggesting that it is possible to use mild environmental stresses to successfully improve the phytochemical content and hence the health-promoting quality of lettuce with little or no adverse effect on its growth or yield. |
| | |
Authors:
|
Myung-Min Oh; Edward E Carey; C B Rajashekar |
Related Documents
:
|
20201804 - The use of beneficial microbial endophytes for plant biomass and stress tolerance impro... 17923374 - Nacl as a physiological modulator of proline metabolism and antioxidant potential in ph... 11800574 - Metabolic engineering of osmoprotectant accumulation in plants. 16665724 - Physiological changes in portulacaria afra (l.) jacq. during a summer drought and rewat... 20724134 - Substitution of peat, fertiliser and manure by compost in hobby gardening: user surveys... 16453764 - Expression of alfalfa mosaic virus coat protein gene confers cross-protection in transg... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't Date: 2009-02-28 |
Journal Detail:
|
Title: Plant physiology and biochemistry : PPB / Société française de physiologie végétale Volume: 47 ISSN: 1873-2690 ISO Abbreviation: Plant Physiol. Biochem. Publication Date: 2009 Jul |
Date Detail:
|
Created Date: 2009-05-25 Completed Date: 2009-08-13 Revised Date: 2009-11-19 |
Medline Journal Info:
|
Nlm Unique ID: 9882449 Medline TA: Plant Physiol Biochem Country: France |
Other Details:
|
Languages: eng Pagination: 578-83 Citation Subset: IM |
Affiliation:
|
Division of Horticulture, Kansas State University, Manhattan, KS 66506, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Adaptation, Physiological* Antioxidants / isolation & purification, metabolism* Ascorbic Acid / metabolism Caffeic Acids / metabolism Chlorogenic Acid / metabolism Flavones / metabolism Galactose Dehydrogenases / metabolism Glucosides / metabolism Lettuce / chemistry, metabolism* Light Methyltransferases / metabolism Phenols / isolation & purification, metabolism* Phenylalanine Ammonia-Lyase / metabolism Quercetin / analogs & derivatives, metabolism Stress, Physiological / physiology* Succinates / metabolism alpha-Tocopherol / metabolism |
| Chemical | |
Reg. No./Substance:
|
0/Antioxidants; 0/Caffeic Acids; 0/Flavones; 0/Glucosides; 0/Phenols; 0/Succinates; 0/luteolin-7-O-glucoside; 117-39-5/Quercetin; 21637-25-2/isoquercitrin; 327-97-9/Chlorogenic Acid; 50-81-7/Ascorbic Acid; 59-02-9/alpha-Tocopherol; 70831-56-0/chicoric acid; EC 1.1.1.-/Galactose Dehydrogenases; EC 1.1.1.48/galactose dehydrogenase; EC 2.1.1.-/Methyltransferases; EC 2.1.1.95/gamma-tocopherol methyltransferase; EC 4.3.1.24/Phenylalanine Ammonia-Lyase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Flow-rate measurements of a dual-phase pipe flow by cross-correlation technique of transmitted radia...
Next Document: Guideline for resuscitation in cardiac arrest after cardiac surgery.