Showing 4 results for Phenol
Volume 11, Issue 1 (10-2011)
Abstract
Aluminum toxicity is one of the most important limiting factors for plant growth and development in acidic soil (pH <5.5). Soil acidity and consequently availability of Al in the soil can be accelerated by some farming practices and acid rain. The mechanisms of Aluminum toxicity have not been elucidated yet. The first response of the plant to aluminium toxicity is the inhibition of root elongation, that is apparently resulted from increasing of cell wall cross links. Therefore, the effect of aluminium on activity and gene expression of enzymes involved in phenolic compounds biosynthesis such as phenylalanine ammonialyase and peroxidase was investigated in this research.To this end, the flax seeds grown in Hoagland’s solution were treated with 0, 50 and 100 &muM aluminium (as AlCl3. 6H2O). The results showed that aluminium decreased root growth but increased wall bound phenolics content, compared with those of the control plants. Increase of the activity of peroxidase especially in ionically and covalently fractions in Al-treated roots was consisted with reducing root growth. Increased activity, PAL expression and lignin contents were observed in higher concentrations of aluminum. The investigation of the expression of peroxidase isozymes, Flxper1 and Flxper3 suggested that Flxper3 is the isozyme which is more involved in aluminium toxicity in flax roots.
Roya Karamian, M Asadbigi, M Ranjbar,
Volume 12, Issue 3 (11-2012)
Abstract
Salvia L. is one of the important genera of the Lamiaceae family, that most of its species have nutritious and medicinal values. This study aimed to examine the total phenol and flavonoid contents and the antioxidant activities of S. aethiopis using spectrophotometric method. The essential oil of this species was analyzed using GC and GC/MS methods. In addition, antibacterial activities of the essential oil and methanolic extract were evaluated against six gram positive and negative bacteria, respectively. Results showed that the extract has high content of phenolic compounds with high antioxidant activity. From GC analysis, 11 different compounds were indentified in which &alpha-copaene was the most abundant compound with 33.48%. The extract of the species showed a high antibacterial activity against Proteus vulgaris. However, the essential oil of S. aethiopis had no effect on examined bacteria.
Roya Karamian, Davoud Ali Hosseini,
Volume 14, Issue 3 (10-2014)
Abstract
The methanol extracts of leaves and bulbs of Allium ampeloprasum L. (Alliaceae) were analyzed for their phenolic profiles and screened for their antioxidant and antibacterial activities. Two biochemical assays, namely DPPH free radical scavenging and &beta-caroten/linoleic acid activity systems, were used to evaluate antioxidant activity. Total phenol and flavonoid contents of the species were determined by Folin-Ciocalteu and AlCl3 assays, respectively. Results indicated that the extracts are different in total phenolic content. Results from antioxidant activity showed that the extracts studied in DPPH radical scavenging assay are lower active than ascorbic acid and BHT as synthetic antioxidants. Antibacterial assay showed that the bulbs extract is more effective in inactivation of Haemophilus influenzae and Bacillus cereus and the leaves extract is more effective in inactivation of Bacillus cereus at 100 mg ml-1 than others. Then, the extracts of Allium ampeloprasum possess strong antioxidant activity and may be used as new drug supplements in the future.
Volume 18, Issue 56 (9-2006)
Abstract
The mechanism of soybean(Glycine max L.cv.Gorgan 3) response to drought stress was evaluated. The plants were grown in pots under 23 ± 2°C temperature and 14000 lux light intensity and 14hr photoperiod. When first leaf appeard, three irrigation treatments occurred that consisted as one every day(control), once in three(mild stress) and in five days(sever stress).During 15 days the plants were irrigated an amount of 150 ml. The effect of irrigation treatment on the soluble sugar, total protein, proline, phenolic compound, chlorophyll content and nitrate reductase activity was studied.The results showed that in the root soluble sugar and proline content in mild and sever stress significantly increased while in the stem and the leaf these compound considarably increased under sever stress the total protein ,chlorophyll a,b and nitrate reductase activity in leaf especially decreased in sever stress. Also the decrease phenolic compound in leaf under this condition was significant