Abstract
Cucumber plants (variety “Kurazh”) had been growing under Philips TL-D 36W/765 fluorescent lamps at 4000 lx with 14 h photoperiod until the beginning of first leaf formation. Then until the appearance of the second leaf (usually 10 d) the plants had been growing under blue (459 nm) or red (635 nm) light-emitting diodes (LEDs) or under blue and red LEDs with red to blue ratio 2:1. Plants grown under white fluorescent lamps were used as a control. All lamps had the same light intensity. Water-soluble phenols content was determined spectrophotometrically and α- and γ-tocopherols contents were determined with HPLC with fluorescent detector. Phenolic peroxidase activity was assayed by guaiacol consumption kinetics at 436 nm.We found that water-soluble phenols and tocopherols levels increase by 80% and 30% under blue LEDs while under red LEDs these levels, conversely, decrease by 30% and 13% compared to control plants. During combined action of red and blue light water-soluble phenols content increased by 55% compared to control. On the other hand tocopherols contents under such lighting were at the level of control. Under red LEDs α- to γ-tocopherol ratio was lower than that under blue light. Previously we showed that monochromatic narrow-band light sources, especially with red light, are considered by plant organism as a stress factor. Low α-tocopherol level detected under red light may be caused by its intensive consumption as an effective quencher of reactive oxygen species and free radicals interceptor. It is not impossible that narrow-band lighting has the inhibiting effect on γ-tocopherol methyltransferase – an enzyme that catalyses γ- to α-tocopherol conversion.Phenolic peroxidase activity changed adversely compared to phenols content – it had the highest value under red LEDs and the lower value under blue LEDs. This is consistent with the fact that it uses phenols as the substrate.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 9
Claim · model-written summary
Blue light raised water soluble phenols 80%.
- Taxon
- Cucumber plants
Cucumis sativust0 - Treatment
- blue LEDse0
- Outcome
- water-soluble phenolse0
- Direction
- increasee0
- Value
- 80%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“water-soluble phenols and tocopherols levels increase by 80% and 30% under blue LEDs”
t0“Cucumber plants”
Claim · model-written summary
Blue light raised tocopherols 30%.
- Taxon
- Cucumber plantsCucumis sativust0
- Treatment
- blue LEDse0
- Outcome
- tocopherolse0
- Direction
- increasee0
- Value
- 30%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“water-soluble phenols and tocopherols levels increase by 80% and 30% under blue LEDs”
t0“Cucumber plants”
Claim · model-written summary
Red light lowered phenols 30%.
- Taxon
- Cucumber plantsCucumis sativust0
- Treatment
- red LEDse0
- Outcome
- levelse0
- Direction
- decreasee0
- Value
- 30%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“under red LEDs these levels, conversely, decrease by 30% and 13% compared to control plants”
t0“Cucumber plants”
Claim · model-written summary
Red light lowered tocopherols 13%.
- Taxon
- Cucumber plantsCucumis sativust0
- Treatment
- red LEDse0
- Outcome
- levelse0
- Direction
- decreasee0
- Value
- 13%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“under red LEDs these levels, conversely, decrease by 30% and 13% compared to control plants”
t0“Cucumber plants”
Claim · model-written summary
Combined light raised phenols 55%.
- Taxon
- Cucumber plantsCucumis sativust0
- Outcome
- water-soluble phenols contente0
- Direction
- increasede0
- Value
- 55%e0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“water-soluble phenols content increased by 55% compared to control”
t0“Cucumber plants”
Claim · model-written summary
Combined light kept tocopherols at control level.
- Taxon
- Cucumber plantsCucumis sativust0
- Outcome
- tocopherols contentse0
- Direction
- at the level of controle0
- Comparator
- controle0
Not reportedTreatment
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“tocopherols contents under such lighting were at the level of control”
t0“Cucumber plants”
Claim · model-written summary
Red light lowered the alpha to gamma tocopherol ratio relative to blue light.
- Taxon
- Cucumber plantsCucumis sativust0
- Treatment
- red LEDse0
- Outcome
- α- to γ-tocopherol ratioe0
- Direction
- lowere0
- Comparator
- blue lighte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under red LEDs α- to γ-tocopherol ratio was lower than that under blue light”
t0“Cucumber plants”
Claim · model-written summary
Phenolic peroxidase activity was highest under red light.
- Taxon
- Cucumber plantsCucumis sativust0
- Outcome
- highest valuee0
- Direction
- higheste0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it had the highest value under red LEDs and the lower value under blue LEDs”
t0“Cucumber plants”
Claim · model-written summary
Phenolic peroxidase activity was lower under blue light.
- Taxon
- Cucumber plantsCucumis sativust0
- Outcome
- lower valuee0
- Direction
- lowere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it had the highest value under red LEDs and the lower value under blue LEDs”
t0“Cucumber plants”