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Showing 94 results for Phenolic Compound


Volume 1, Issue 3 (9-2012)
Abstract

The biocontrol activity of two isolates of Candida membranifaciens against grey mold of apple fruit caused by Botrytis mali and their ability to induce biochemical defense responses in apple tissue were investigated. Apple fruit (Malus domestica) wounds were inoculated with 50 µl yeast suspension (1 × 107 CFU/ml) of C. membranifaciens followed 4 h later by 20 µl of conidial suspension of B. mali (1 × 105 conidia/ml). The apples were then incubated at 20 ºC for 8 days. Lesion diameter sizes were measured 4 and 8 days after pathogen inoculation. In addition to controlling grey mold, these two isolates of C. membranifaciens caused increases in peroxidase and β-1, 3-glucanase activities. These isolates also caused inhibition in catalase activity. The accumulation of phenolic compounds was increased in apple fruit treated with antagonists and inoculated with B. mali and reached its highest level 6 days after treatment. The ability of C. membranifaciens to affect H2O2-metobolizing enzymes and increase levels of β-1, 3-glucanase activity and phenolic compounds may be some of mechanisms responsible for its biocontrol activity.  

Volume 4, Issue 3 (9-2015)
Abstract

Some plant extracts have been reported to exhibit antimicrobial properties. Plant based pesticides appear to be an alternative for the synthetic pesticides because of their less dangerous impacts. The objective of this study was to assess the inhibitory activity of Brassica napus water extract on mycelial growth of six phytopathogenic fungi Rhizoctonia solani, Phythophtora drechseleri, Pythium aphanidermatum, Verticellium dahliae, Fusarium oxysporum, and Gaeumannomyces graminis. Antifungal activity test was performed by disc diffusion method. Concentrations of 100 and 50 ppm had the highest and the lowest inhibitory effects on all studied species respectively. The shoot extract (SE) was significantly exerted higher antifungal activity than root extract (RE). At 100 ppm, V. dahliae (17.02% inhibition by RE) and F. oxysporum (50% inhibition by SE) were the most sensitive species however, R. solani (1.8 and 15%) was the most resistant fungus to both extracts. Active compounds of B. napus extract were determined by high performance liquid chromatography (HPLC). Phenolic compounds had the highest concentrations in extracts and are probably the main cause of the mycelial growth inhibition. Application of canola aqueous extract or incorporation of canola in crop rotation program can be considered as a method for management of some soil-borne phytopathogenic fungi.

Volume 5, Issue 1 (6-2016)
Abstract

Solvent extraction and taguchi method were used to optimize conditions for the antioxidant activity of Azolla fern extracts. The independent processing variables were ethanol concentration, extraction time and solid to solvent ratio. Ethanol concentration and solvent to solid ratio significantly affected antioxidant activity measured by the total phenol content (p < 0.05). whereas the extraction time did not significantly affect the activity (p > 0.05). Antioxidant activity of the extracts, determined by the total phenolic content, varied from 5.77 to 16.42 mg acid gallic equivalents/g of dry sample. DPPH scavenging activity percentage ranged from %20.51 to %93.71. Ethanol concentration of %50 and sample to solvent ratio of 1 to 15 were optimal for the highest antioxidant activities measured by the TPC assay and the DPPH method. The optimal extraction time was 48h. The result show that azolla fern is suitable for antioxidant extraction.

Volume 5, Issue 18 (10-2008)
Abstract

  In this experiment, acetone was used to extract the phenolic compounds of grape pomace by colorimetric method (Folin-Ciocalteu). The phenolics extract levels of 50, 150, 250 and 350 ppm were used to assess their antioxidant activity in raw soybean oil. On day 0, 4, 8 and 12 the proxide value for soybean oil was estimated. Also, the TBA value for soybean oil on day 0, 5, 9 and 13 was estimated. The results showed that the phenolic compounds whose content in grape pomace is 64 g/kg DM has an antioxidant activity. The level of 150 ppm of tannin extract from grape pomace showed a desirable activity to prevent the oxidation of raw soybean oil. The antioxidant activity of this level was higher than those obtained by the level 200 ppm from synthetic antioxidants. Therefore, the use of phenolic compound in grape pomace as natural antioxidants can be recommended.  

Volume 6, Issue 1 (2-2020)
Abstract

Aims: The aim of this study was to investigate chemical composition, antioxidant potential, and antimicrobial activity of cardamom essential oil against Staphylococcus aureus, Escherichia coli, and Saccharomyces cerevisiae species.
Materials & Methods: The chemical compositions of cardamom essential oil were identified by Gas Chromatography-Mass Spectrometry (GC-MS) device. Cardamom essential oil antioxidant activity was measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay, and its total phenolic compounds (TPC) were measured by Folin–Ciocalteu reagent. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of cardamom essential oil were determined using the serial-dilution method.
Findings: According to the GC-MS analysis results, 17 compounds were totally identified in cardamom essential oil, among which the most important compounds were 1, 8-cineole (36.74%) and α-terpinyl acetate (33.07%). MICs obtained for S. aureus, E. coli, and S. cerevisiae were 12.50, 25.00, and 1.56 mg/mL, respectively. Also, MBC obtained for both S. aureus and E. coli was 25 mg/mL, while MBC for S. cerevisiae was 3.36 mg/mL. Antioxidant activity measurement results showed that increasing the amount of cardamom essential oil reduced the amount of color and absorbance of DPPH solution to 517 nm. The results also showed that the amount of TPC in cardamom essential oil was 214.35 mg gallic acid per 100 g of dry material.
Conclusion: Cardamom essential oil used in this study showed antibacterial and anti-yeast activities against S. aureus, E. coli, and S. cerevisiae species. Antimicrobial effects of cardamom essential oil were predictable due to the presence of antimicrobial components in this oil.

Volume 6, Issue 2 (11-2015)
Abstract

Free radicals, having one or more unpaired electrons in the outer orbit, which are oxygen-centred free radicals, sometimes known as reactive oxygen species (ROS). The oxidative stress imposed by ROS plays an important role in many chronic and degenerative diseases. The aim of the present research was undertaken to study the antioxidant activity and polyphenolic content in the different extracts of sea urchin Echinometra mathaei. Different extracts (spine, shell, gonad and aristotol lantern) of sea urchin were isolated by three solvents (n- hexan, ethyl acetate, methanol). Antioxidant activity of extracts was assessed by measured reducing power, DPPH free radical scavenging activity and total antioxidant capacity assays, and compared with the synthetic antioxidant butylated hydroxytoluent (BHT) and Ascorbic acid. Total phenolic and flavonoid contents were measured spectrophotometrically. According to the results of the study, highest the reducing power and free radical-scavenging activity of the methanolic shell and methanolic spine, respectively. In total antioxidant capacity assay, the antioxidant activity of aristotol lantern ethyl acetate, spine and gonad n-hexan was higher as compared to that of the ascorbic acid. The highest total phenol and flavonoid compound content per gram of the methanolic spine were 0.0044±0.0003 mg gallic acid equivalents and 24.616±0.7167 mg quercetin equivalents, respectively. Significant differences were observed at P

Volume 6, Issue 2 (9-2017)
Abstract

The extraction of hydrocolloids from seaweeds is associated with production of secondary metabolites during pretreatment step. In this study, the antioxidant properties were evaluated for secondary metabolites from brown seaweed S. angustifolium. The crude extract obtained by 80% ethanol for four hours and then partitioned using hexane, chloroform, ethyl acetate and water. The extraction yield was found to be 4% for crude extract and varied between 2.8-43% for fractions. The evaluation of antioxidant properties revealed a successful solvent fractionation in portioning antioxidant compounds. Among various fractions, ethyl acetate exhibited the highest activity in DPPH radical scavenging (75.78%), ABTS radical scavenging (88.92%), reducing power (67.54%) and total antioxidant (0.34 Abs) capacities. The highest amount of phenolic contents was found in ethyl acetate fraction (277.86 mg/ TA in extract) while the lowest amount was in aqueous fraction (21.36 mg/ TA in extract). The highest correlation (R2 = 0.88) was observed between total phenolic content and total antioxidant activity. Overall, the results of current study show that ethanol extract of S. angustifolium contains major bioactive compounds suggesting its potential application in food industry as a natural antioxidant.  

Volume 6, Issue 3 (12-2017)
Abstract

Nowadays, replacement of the synthetic antioxidants by natural ones has been noticed in the food industry. Seaweeds with rich sources of antioxidant compounds will be excellent choice for this purpose. In the study Effect of the use of water and different organic solvents such as acetone, ethanol and methanol 50% on the total polyphenol content and antioxidant activity was studied for two species of red algae Hypnea hamulosa and Gracilaria corticata of Persian Gulf. Extraction was performed using conventional solvent extraction method and the ratio of 1:20 algae: solvent. The results indicated that acetone extracts (50%) had the highest values in the total phenol contents (0.31 mg tannic acid / g algal powder), ferric reducing antioxidant power (0.06 mg tannic acid / g algal powder), DPPH radical scavenging activity 76.11% (p<0.05). Total antioxidant activity of this extract showed no significant difference with ethanolic extracts (50%) and aqueous extract (p> 0.05). Comparison of two algal species showed that in all factors except total antioxidant activity, algal species Gracilaria corticata had a higher antioxidant activity (p<0.05). Therefore conclude that solvents with different polarities have a significant effect on total phenolic content and antioxidant activity.

Volume 8, Issue 2 (10-2017)
Abstract

in recent years, interest in use of plant sources due to function of Phytochemicals and antioxidant compound in maintenance of human health is increased, phenolic and flavonoid compounds are one of important compounds of plants that have antioxidant effects. Aim of the present study is to examine and comparison of phenolic and flavonoid compounds and antioxidant capacity of different organs of saffron, that every year a huge amount of them are wested during the processing of stigma. In this study, different parts of saffron were extracted by methanol (80%), then the amount of total phenol and flavonoid compounds was assayed by means of Folin-Ciocalteu and and Aluminium choloride methods respectively. The antioxidant activity was measured by DPPH free radical reduction. According to the results of this study, The highest content of total phenolic(6.43 mg GAE g-1 DW) and flavonoid (1.33 mg RU g-1 DW) was observed in stigma compared to other organs. The result of DPPH test also showed higher antioxidant capacity of stigma in comparison to other organs. Comparison of phenolic compounds in various organs showed that the content of these compounds and antioxidant activity could be different related to type of organs. Also, the higher antioxidant capacity in stigma and tepal compared to leaf and corm could be as a result of more phenolic compounds in these organs.

Volume 8, Issue 28 (4-2011)
Abstract

  In the present study the effects of extract from the peels of Ramus potato variety as a natural antioxidant in refined soybean oil were investigated using the Schaal oven and Rancimat methods. Phenolic antioxidants of potato peels were extracted by two different solvent extraction methods (Solvent with methanol and ultrasound-assisted method with different solvents including methanol, ethanol, hexane, acetone and water ). The total phenolic compounds were determined according to the Folin–Ciocalteu method. Maximum amount of extract was obtained with water, followed by methanol and ethanol but maximum amount of phenolics was obtained                                                            with methanol, followed by water and ethanol by ultrasound method. Sonication improved the total phenolic compounds of the potato peel extract and shortened the extraction times.                                                                                                   After 16 days storage at 63°C,soy bean oil containing 200, 800, 1600, and 2400 ppm of  methanolic extract of potato peels, attained lower peroxide values (PV , 42.67 , 37.35 , 24.65 and 19.09 meq/kg, respectively) than the control sample (PV , 64.08 meq/kg ) indicating strong antioxidant activity. Oils treated with 200 ppm of BHA, BHT and TBHQ attaind PVs of 33.20 , 28.88 and 9.96 meq/kg, respectively, after 16 days storage at 63°C. Also, results Rancimat (at 90,120,150°C) showed that potato peel extract, at concentrations of 1600 and 2400 ppm exhibited strong antioxidant activity which was almost equal to synthetic antioxidants (BHA & BHT).                                                                                                                                                     

Volume 8, Issue 28 (4-2011)
Abstract

  Phenolic compounds, especially those of plants origin, are an essential part of the human diet, and are of considerable interest due to their antioxidant properties. The total phenolics content (TPC) and antioxidant and antimicrobial activities of pistachio green hull methanolic extracts of five different cultivars (Fandoghi, Kaleghochi, Ahmadaghai, Forotani and Seyed ali aghai) were studied. TPC ranged from 15.3 mg/g of GAE (cv. Kaleghochi) to 31.1 mg/g of GAE (cv. Ahmadaghai). The antioxidant capacity of extracts was assessed through DPPH and ABTS methods. A concentration-dependent antioxidative capacity was verified in both methods for all the cultivars. Antioxidant activity of Ahmadaghai cultivar in both methods was more than the other cultivars. The antimicrobial capacity was screened against Gram positive and Gram negative bacteria, and fungi. All the extracts inhibited the growth of Gram positive bacteria of Bacillus cereus and Staphylococcus aureus. Bacillus cereus was more susceptible than Staphylococcus aureus for all the extracts. The results obtained in this study showed that pistachio green hull can be used as a cheap and easily accessible source of natural bioactive compounds.

Volume 8, Issue 34 (12-2011)
Abstract

To evaluate antioxidant activity of some natural phenolics , tallow olein was employed as a lipid system. Since  animal fats are weak in natural antioxidants, studying antioxidant activity will provide a desirable behavior profile for them. Edible sheep tail fat was effectively fractionated by acetone crystallization at constant  temperatures of 25, 15 and 5°C. In order to stabilize mutton tallow olein, antioxidant activities of some phenolic compounds including gallic acid, caffeic acid, catechin,quercetin, tannic acid, ellagic acid and salicylic acid were studied in tallow olein as a lipid system ,at 150 ° C at 40 , 60 ,80 ,100 ,200 and 400 mg/L concentrations, by measuring induction time.  Rancimat apparatus was employed as a mean to evaluate the antioxidant activity. The results indicated that gallic acid had the highest stabilizing effect on tallow olein while ellagic acid had the least effect as primary antioxidants. Among phenolic compounds investigated, only salicylic acid showed no antioxidant activity which is in contrast to all other antioxidant compounds. The results showed that, in tallow olein, the antioxidant activities of the ellagic and tannic acid are comparable to α-tocopherol whereas quercetin, catechin, gallic acid and caffeic acid are much more potent than α-tocopherol.  
P. Yasoubi, M. Barzegar, M. A. Sahari, M. H. Azizi,
Volume 9, Issue 1 (1-2007)
Abstract

The phenolic compounds of pomegranate (Punica granatum L.) peel extracted by two methods (solvent and ultrasound-assisted) with five solvents (acetone, methanol, ethanol, water and ethyl acetate) were compared with supercritical fluid extraction (SFE). The total phenolic compounds were determined according to the Folin-Ciocalteu reagent using tannic acid as standard. The overall results showed that acetone with sonication produced the maximum amount of phenolic compounds from pomegranate peel extracts (PPE). Furthermore, the effect of the acetone extract of pomegranate peel (0.010-0.050 %) on the stability of soybean oil during heating at 60oC (oven test method) was determined by measuring peroxide and thiobarbitoric acid values. At a 0.050 % level of pomegranate peel extract, its antioxidant activity was greater than 0.02 % of the two synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). The pomegranate peel extract possessed a relatively high antioxidant activity and might be considered as a rich source of natural antioxidant.

Volume 9, Issue 1 (12-2020)
Abstract

One critical environmental stress that limits plant production and development is salinity stress. Recently it has been shown that application of plant growth-promoting rhizobacteria (PGPR) can alleviate the deleterious effects of environmental stresses. Present study aimed to evaluate the effects of some bacterial strains on proline, sugar, total phenolic compounds (TPC), Phenylalanine ammonia lyase (PAL), photosynthetic pigments and antioxidant activities (guaiacol peroxidase, polyphenol oxidase and superoxide dismutase) of cucumber plants under salinity stress. A completely randomized design was applied with a factorial arrangement of two factors: salinity at three levels (0, 50 and 100 mM) and Pseudomonas fluorescens and Bacillus subtilis strains, with three replications. The results showed that cucumber plants that were inoculated with Pseudomonas and Bacillus strains possessed noticeable variations in proline, sugar, TPC, PAL and enzymes activity compared to un-inoculated control. These results suggest that use of these bacterial strains overcame harmful effect of salinity by accumulation of proline, TPC, sugar, PAL activity and enzymes activity that can be considered as a suitable method to manage salinity stress.

Volume 9, Issue 3 (8-2020)
Abstract

Brown algae are a valuable source of natural antioxidant compounds, especially Phlorotannins. In this study, the effect of solvent concentration (water / ethanol) on the the amount of Phlorotannin compounds and antioxidant properties of extracts from brown alga Sargassum angustifolium were investigated. The extraction was performed by solvent method at room temperature (28-26 °C) with ethanol/ water solvent with three ratios (30:70), (50:50) and (70:30). The amount of Phlorotannin, total phenolic content, ferric reducing antioxidant power, DPPH radical scavenging activity and total antioxidant capacity of different extracts were evaluated. The results showed that the yield of Phlorotannin extraction was dependent on the solvent concentration and with increasing polarity of the solvent, its amount increased, So its amount in ethanol/ water treatment (30:70) is significantly more than the other two treatments (P<0.05). Also, the highest amount of DPPH radical scavenging activity was obtained in ethanol/ water treatments 50:50 and 70:30 which contained less Phlorotannin. Finally, it was found that the ethanol/ water treatment 30:70 of the brown alga Sargassum angustifolium was a good choice for extracting Phlorotannin compounds as a natural bioactive compound for food and medicine purposes.

Volume 11, Issue 44 (2-2014)
Abstract

Apricot fruit consumption increased during past decades because of fruit is a rich source of carotenoids, polyphenol compounds, micro and macro element and vitamins. Current study was carried out to monitored quality changes during fruit ripening and post-harvest period. ‘Asgarabadi’ cultivar fruit was stored at 1 0C and sampling was carried out in 0, 1, 7, 14 and 21 days. Some fruit quality attributes such as soluble solid content (SSC), titrable acidity (TA), carotenoid content, flesh color, total phenol (TP) and fruit antioxidant activity was monitored. SSC increased from 15.5 to 17.7 during experiment while TA was decreased. Carotenoid content was increased and it was accompanied with decrease in color index. TP was 101 mg Gallic acid in 100 g of fresh weight and there were no significant changes during experiment. The evaluation of result indicated that low temperature storage prolonged fruit postharvest life, maintain TP content and improved carotenoid content and color although some antioxidant parameters decreased  

Volume 11, Issue 45 (3-2014)
Abstract

Walnut green husk is waste of walnut that can be valuable source of natural compounds with antioxidant properties. In this study, the effect of regions (Shahrood, Bandar Gaz and Hzargarib),solvent (ethanol 96%, Water and ethanol - water (1:1 v/v)) and extraction time (6 to 24 hours) on the yield of extracted phenolic compounds from walnut green husk has been analyzed. Immersion method at room temperature in a factorial experiment with three replications in a completely randomized design has been used. Then, bioactive properties of walnut green husk extract in a completely randomized design have been compared. The total phenol content of the extract was determined by the method of Folin- ciocalteau. Antioxidant activity of the extract by the reducing power of Iron III and DPPH free radical scavenging ability was evaluated. The results of this study showed that, the solvent polarity, time extraction and plant habitat are effective on amount of extracted phenolic compounds; and also antioxidant activity of the extract depends on the concentration of phenolic compounds. The highest phenolic compounds with 49.66 mg/g (based on Galic acid) were achieved from Hezar jerib walnut green husks with water - ethanol solvent (1:1 v/v) for 24 hours. Also, the most antioxidant properties of the extracts were shown in this extract.

Volume 12, Issue 3 (9-2021)
Abstract

Aims The secondary metabolites of plants have been considered due to their diversity and roles in plants and human health. Grapevine is one of the plants that have secondary compounds with medicinal properties. such compounds include resveratrol which is a phenolic compound from the stilbenoid group. In order to investigate the resveratrol production under the effect of an elicitor, a CRD design with four replications using Soltani cultivar was done.
Materials & Methods. The salicylic acid (SA) was used as an elicitor with variable concentrations including 0, 10-4, 10-5, 10-6 and was introduced into MS medium without hormones to examine it`s stress effects. At the molecular level, the effect of SA on the expression of stilbene-synthase gene was evaluated by semi-quantitative RT-PCR. In the biochemical experiment, the rate of resveratrol production was measured by HPLC.
Findings Stilbene-synthase expression analysis showed that SA with a concentration of 10-4 M had a positive and incremental effect on gene expression and showed a 35.48% of increase compared to the control state, and also the concentration of 10-5 M increased the gene expression 5.65% in relation with control state. In the biochemical experiment, increasing in production of resveratrol was observed in 10-4 M treatment compared to the control treatment (6.1 µg) and 10-5 M treatment (3.25 µg) did not show a significant difference with the control sample.
Conclusion SA as an elicitor and stimulant of resveratrol production could enhance the expression of stilbene-synthase gene followed by enhancing the medicinal properties of the Vitis plant.
A. Rajaei, M. Barzegar, Z. Hamidi, M. A. Sahari,
Volume 12, Issue 5 (10-2010)
Abstract

Phenolic compounds, especially those of plant origin, constitute an essential part of the human diet, and are of considerable interest due to their antioxidant properties. In this study, Ultrasound-Assisted Extraction (UAE), Microwave-Assisted Extraction (MAE), as well as Maceration Extraction (ME) methods were applied for phenolic compounds’ extraction from pistachio green hull. Response surface methodology was employed to optimize the extraction conditions as regards the yield of the compounds. A Central Composite Design (CCD) was employed to investigate the effects of three independent variables, namely liquid-to-solid ratio (8-20 times), temperature (25-65 °C) and time (5-45 minutes) on the dependent variable (level of total phenolic compounds). The results indicated that within the same extraction time, the extraction yield through UAE was higher than those in ME and MAE methods. Correlation coefficients (R2) of the models for UAE, MAE and ME methods were 0.95, 0.96 and 0.94, respectively. The optimal conditions for extraction of phenolic compounds from pistachio green hull through ME, UAE, and MAE methods were 20(v/w), 65°C, 45 minutes; 20(v/w), 65°C, 25 minutes; and 20(v/w), 65°C, 45 minutes, respectively. Under optimized conditions the experimental values well agreed with the values predicted by the proposed models.

Volume 12, Issue 46 (5-2015)
Abstract

  Antioxidants have a wide range of application in food industry. Beside by attention to rising in universal attitude to use from natural antioxidants, at this study antioxidant extracts of barberry fruits extracted by subcritical water at 120 – 180 °C and 10 – 50 Bar and radical scavenging power, reduction power, stability power of edible oil matrix and amount of Total Phenolic Compounds (TPC) of extracts investigated in Folin method. Results showed that amount of Total Phenolic Compounds changed from 2073.81 until 2553.79 mg Gallic acid per 100 grams of Dry Material (mg G.A/100 g D.M) that maximum of Total Phenolic Compounds, observed at 160 °C and decreased with rising temperature, whereas radical scavenging power and stability power in edible oil of extracts increase with temperature. Optimization of extraction process did at different temperatures and pressures condition for receive to maximum amount of Total Phenolic Compounds, stability power, reduction and radical scavenging.  

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