Community Analysis and Recovery of Phenol-degrading Bacteria from Drinking Water Biofilters.

PubMed

Gu, Qihui; Wu, Qingping; Zhang, Jumei; Guo, Weipeng; Wu, Huiqing; Sun, Ming

2016-01-01

Phenol is a ubiquitous organic contaminant in drinking water. Biodegradation plays an important role in the elimination of phenol pollution in the environment, but the information about phenol removal by drinking water biofilters is still lacking. Herein, we study an acclimated bacterial community that can degrade over 80% of 300 mg/L phenol within 3 days. PCR detection of genotypes involved in bacterial phenol degradation revealed that the degradation pathways contained the initial oxidative attack by phenol hydroxylase, and subsequent ring fission by catechol 1,2-dioxygenase. Based on the PCR denatured gradient gel electrophoresis (PCR-DGGE) profiles of bacteria from biological activated carbon (BAC), the predominant bacteria in drinking water biofilters including Delftia sp., Achromobacter sp., and Agrobacterium sp., which together comprised up to 50% of the total microorganisms. In addition, a shift in bacterial community structure was observed during phenol biodegradation. Furthermore, the most effective phenol-degrading strain DW-1 that correspond to the main band in denaturing gradient gel electrophoresis (DGGE) profile was isolated and identified as Acinetobacter sp., according to phylogenetic analyses of the 16S ribosomal ribonucleic acid (rRNA) gene sequences. The strain DW-1 also produced the most important enzyme, phenol hydroxylase, and it also exhibited a good ability to degrade phenol when immobilized on granular active carbon (GAC). This study indicates that the enrichment culture has great potential application for treatment of phenol-polluted drinking water sources, and the indigenous phenol-degrading microorganism could recover from drinking water biofilters as an efficient resource for phenol removal. Therefore, the aim of this study is to draw attention to recover native phenol-degrading bacteria from drinking water biofilters, and use these native microorganisms as phenolic water remediation in drinking water sources.

Phenolic composition and antioxidant potential of grain legume seeds: A review.

PubMed

Singh, Balwinder; Singh, Jatinder Pal; Kaur, Amritpal; Singh, Narpinder

2017-11-01

Legumes are a good source of bioactive phenolic compounds which play significant roles in many physiological as well as metabolic processes. Phenolic acids, flavonoids and condensed tannins are the primary phenolic compounds that are present in legume seeds. Majority of the phenolic compounds are present in the legume seed coats. The seed coat of legume seeds primarily contains phenolic acids and flavonoids (mainly catechins and procyanidins). Gallic and protocatechuic acids are common in kidney bean and mung bean. Catechins and procyanidins represent almost 70% of total phenolic compounds in lentils and cranberry beans (seed coat). The antioxidant activity of phenolic compounds is in direct relation with their chemical structures such as number as well as position of the hydroxyl groups. Processing mostly leads to the reduction of phenolic compounds in legumes owing to chemical rearrangements. Phenolic content also decreases due to leaching of water-soluble phenolic compounds into the cooking water. The health benefits of phenolic compounds include acting as anticarcinogenic, anti-thrombotic, anti-ulcer, anti-artherogenic, anti-allergenic, anti-inflammatory, antioxidant, immunemodulating, anti-microbial, cardioprotective and analgesic agents. This review provides comprehensive information of phenolic compounds identified in grain legume seeds along with discussing their antioxidant and health promoting activities. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lag phase and biomass determination of Rhodococcus pyridinivorans GM3 for degradation of phenol

NASA Astrophysics Data System (ADS)

Al-Defiery, M. E. J.; Reddy, G.

2018-05-01

Among various techniques available for removal of phenol, biodegradation is an eco-friendly and cost effective method. Thus, it is required to understand the process of biodegradation of phenol, such as investigate on lag phase and biomass concentration. Phenol degrading bacteria were isolated from soil samples of industrial sites in enriched mineral salts medium (MSM) with phenol as a sole source of energy and carbon. One isolate of potential phenol degradation from consortium for phenol degrading studies was identified as Rhodococcus pyridinivorans GM3. Lag phase and biomass determination of R. pyridinivorans GM3 was studied with different phenol concentrations under pH 8.5 at temperature 32 Co and 200 rpm. Microbial biomass was directly proportional to increasing phenol concentration between 1.0 to 2.0 g/L with a maximum dry biomass of 1.745 g/L was noted after complete degradation of 2.0 g/L phenol in 48 hours.

Solid/liquid extraction equilibria of phenolic compounds with trioctylphosphine oxide impregnated in polymeric membranes.

PubMed

Praveen, Prashant; Loh, Kai-Chee

2016-06-01

Trioctylphosphine oxide based extractant impregnated membranes (EIM) were used for extraction of phenol and its methyl, hydroxyl and chloride substituted derivatives. The distribution coefficients of the phenols varied from 2 to 234, in the order of 1-napthol > p-chlorophenol > m-cresol > p-cresol > o-cresol > phenol > catechol > pyrogallol > hydroquinone, when initial phenols loadings was varied in 100-2000 mg/L. An extraction model, based on the law of mass action, was formulated to predict the equilibrium distribution of the phenols. The model was in excellent agreement (R(2) > 0.97) with the experimental results at low phenols concentrations (<800 mg/L). At higher phenols loadings though, Langmuir isotherm was better suited for equilibrium prediction (R(2) > 0.95), which signified high mass transfer resistance in the EIMs. Examination of the effects of ring substitution on equilibrium, and bivariate statistical analysis between the amounts of phenols extracted into the EIMs and factors affecting phenols interaction with TOPO, indicated the dominant role of hydrophobicity in equilibrium determination. These results improve understanding of the solid/liquid equilibrium process between phenols and the EIMs, and these will be useful in designing phenol recovery process from wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Profile and Bioaccessibility of Phenolic Compounds in Cereals Influenced by Improved Extrusion Cooking Treatment

PubMed Central

Zeng, Zicong; Liu, Chengmei; Luo, Shunjing; Chen, Jun; Gong, Ersheng

2016-01-01

The aim of this study was to investigate the effect of Improved Extrusion Cooking Treatment (IECT) on the phenolics and its bioaccessibility in cereals, represented by brown rice, wheat, and oat. Data showed that total phenolic content and total antioxidant activity in free form were significantly decreased, while the bound form was increased after IECT. After IECT, the total free phenolic acids of brown rice and wheat were significantly decreased by 5.88% and 45.66%, respectively, while the total bound phenolic acids of brown rice, wheat, and oat were significantly increased by 6.45%, 8.78%, and 9.10%, respectively. Brown rice provided the most bioaccessible phenolics and antioxidant compounds, followed by oat and wheat. IECT significantly decreased the bioaccessible phenolics of brown rice and oat by 31.09% and 30.95%, while it had minimal effect on the bioaccessible phenolics of wheat. These results showed that IECT greatly affected the phenolics and its bioaccessibiltiy of cereals, with the effect depending on cereal matrix and the sensitivity of free and bound phenolics. Furthermore, bioaccessible phenolic acids of raw and processed cereals were considerably low, and it slightly contributed to the bioaccessible phenolics. PMID:27513581

VUV/UV light inducing accelerated phenol degradation with a low electric input.

PubMed

Li, Mengkai; Wen, Dong; Qiang, Zhimin; Kiwi, John

2017-01-23

This study presents the first evidence for the accelerated degradation of phenol by Fenton's reagent in a mini-fluidic VUV/UV photoreaction system (MVPS). A low-pressure mercury lamp used in the MVPS led to a complete degradation of phenol within 4-6 min. The HO˙ and HO 2 ˙ originating from both Fenton's reagent and VUV photolysis of water were identified with suitable radical scavengers. The effects of initial concentrations of phenol, H 2 O 2 and Fe 3+ as well as solution pH on phenol degradation kinetics were examined. Increasing the initial phenol concentration slowed down the phenol degradation, whereas increasing the initial H 2 O 2 or Fe 3+ concentration accelerated the phenol degradation. The optimal solution pH was 3.7. At both 254 and 185 nm, increasing phenol concentration enhanced its absorption for the incident photons. The reaction mechanism for the degradation of phenol was suggested consistent with the results obtained. This study indicates that the VUV/UV photo-Fenton process has potential applications in the treatment of industrial wastewater containing phenol and related aromatic pollutants.

Phenolic profile and in vitro antioxidant capacity of insoluble dietary fiber powders from citrus (Citrus junos Sieb. ex Tanaka) pomace as affected by ultrafine grinding.

PubMed

Tao, Bingbing; Ye, Fayin; Li, Hang; Hu, Qiang; Xue, Shan; Zhao, Guohua

2014-07-23

The effects of mechanical and jet grindings on the proximate composition, phenolics, and antioxidant capacity of insoluble antioxidant dietary fiber powder from citrus pomace (IADFP-CP) were investigated in comparison with ordinary grinding. IADFP-CP from jet grinding showed higher levels of crude fat, total sugar, and free phenolics and lower levels of crude protein and bound phenolics than that from ordinary grinding. Totally, 14 phenolics (9 free, 1 bound, and 4 free/bound) in IADFP-CP were identified by RP-HPLC-DAD/ESI-Q-TOF-MS/MS. Hesperidin accounted for >57% of total phenolics in IADFP-CP. Among IADFP-CPs, the jet-ground presented the highest free phenolics but the lowest bound phenolics. The IADFP-CP from jet grinding presented the highest antioxidant capacity of free phenolics (by DPPH and FRAP assays), followed by the ones from mechanical and then ordinary grinding. The present study suggests that jet grinding could improve the extraction of phenolic compounds from IADFP-CP and increase the antioxidant capacities of free phenolics and the resultant powder.

Cocarcinogenicity of phenols from Estonian shale tars (oils).

PubMed Central

Bogovski, P A; Mirme, H I

1979-01-01

Many phenols have carcinogenic activity. The Estonian shale oils contain up to 40 vol % phenols. The promoting activity after initiation of phenols of Estonian shale oils was tested in mice with a single subthreshold dose (0.36 mg) of benzo(a)pyrene. C57Bl and CC57Br mice were used in skin painting experiments. Weak carcinogenic activity was found in the total crude water-soluble phenols recovered from the wastewater of a shale processing plant. In two-stage experiments a clear promoting action of the total crude phenols was established, whereas the fractions A and B (training reagents), obtained by selective crystallization of the total phenols exerted a considerably weaker promoting action. Epo-glue, a commercial epoxy product produced from unfractionated crude phenols, had no promoting activity, which may be due to the processing of the phenols involving polymerization. The mechanism of action of phenols is not clear. According to some data from the literature, phenol and 5-methylresorcinol reduce the resorption speed of BP in mouse skin, causing prolongation of the action fo the carcinogen. PMID:446449

Cocarcinogenicity of phenols from Estonian shale tars (oils).

PubMed

Bogovski, P A; Mirme, H I

1979-06-01

Many phenols have carcinogenic activity. The Estonian shale oils contain up to 40 vol % phenols. The promoting activity after initiation of phenols of Estonian shale oils was tested in mice with a single subthreshold dose (0.36 mg) of benzo(a)pyrene. C57Bl and CC57Br mice were used in skin painting experiments. Weak carcinogenic activity was found in the total crude water-soluble phenols recovered from the wastewater of a shale processing plant. In two-stage experiments a clear promoting action of the total crude phenols was established, whereas the fractions A and B (training reagents), obtained by selective crystallization of the total phenols exerted a considerably weaker promoting action. Epo-glue, a commercial epoxy product produced from unfractionated crude phenols, had no promoting activity, which may be due to the processing of the phenols involving polymerization. The mechanism of action of phenols is not clear. According to some data from the literature, phenol and 5-methylresorcinol reduce the resorption speed of BP in mouse skin, causing prolongation of the action fo the carcinogen.

The regulation by phenolic compounds of soil organic matter dynamics under a changing environment.

PubMed

Min, Kyungjin; Freeman, Chris; Kang, Hojeong; Choi, Sung-Uk

2015-01-01

Phenolics are the most abundant plant metabolites and are believed to decompose slowly in soils compared to other soil organic matter (SOM). Thus, they have often been considered as a slow carbon (C) pool in soil dynamics models. Here, however, we review changes in our concept about the turnover rate of phenolics and quantification of different types of phenolics in soils. Also, we synthesize current research on the degradation of phenolics and their regulatory effects on decomposition. Environmental changes, such as elevated CO2, warming, nitrogen (N) deposition, and drought, could influence the production and form of phenolics, leading to a change in SOM dynamics, and thus we also review the fate of phenolics under environmental disturbances. Finally, we propose the use of phenolics as a tool to control rates of SOM decomposition to stabilize organic carbon in ecosystems. Further studies to clarify the role of phenolics in SOM dynamics should include improving quantification methods, elucidating the relationship between phenolics and soil microorganisms, and determining the interactive effects of combinations of environmental changes on the phenolics production and degradation and subsequent impact on SOM processing.

Chemopreventive effects of free and bound phenolics associated to steep waters (nejayote) obtained after nixtamalization of different maize types.

PubMed

Rojas-García, Carlos; García-Lara, Silverio; Serna-Saldivar, Sergio O; Gutiérrez-Uribe, Janet A

2012-03-01

Free and bound phenolics extracts from nejayote solids were obtained after optimally lime-cooking blue, normal white, red, normal yellow, high-carotenoid and quality protein maize types. The extraction yield ranged from 4.47 to 10.05%. Bound phenolics extracts had higher content of total phenolics, antioxidant activity and ferulic acid compared to the free phenolics extracts. In general, free phenolics extracts were less cytotoxic than the bound phenolics counterparts. Bound phenolics extracts had higher induction of quinone reductase (QR) and particularly the normal yellow nejayote exerted the highest chemopreventive index tested in Hepa1c1c7 cells. When tested for monofunctional phase 2 induction capacity in BPrc1 cells, the bound phenolics extracts of blue, normal white and quality protein nejayotes were better inducers than the normal yellow counterpart. Particularly, the free phenolics extract of the white maize nejayote induced BPrc1 cells QR and exerted a higher chemopreventive index compared to the bound phenolics extract. Therefore, the nejayote of the normal white maize was the best source of monofunctional phase 2 enzyme inducers.

Phenol separation from phenol-laden saline wastewater by membrane aromatic recovery system-like membrane contactor using superhydrophobic/organophilic electrospun PDMS/PMMA membrane.

PubMed

Ren, Long-Fei; Adeel, Mister; Li, Jun; Xu, Cong; Xu, Zheng; Zhang, Xiaofan; Shao, Jiahui; He, Yiliang

2018-05-15

Phenol recovery from phenol-laden saline wastewater plays an important role in the waste reclamation and pollution control. A membrane aromatic recovery system-like membrane contactor (MARS-like membrane contactor) was set up in this study using electrospun polydimethylsiloxane/polymethyl methacrylate (PDMS/PMMA) membrane with 0.0048 m 2 effective area to separate phenol from saline wastewater. Phenol and water contact angles of 0° and 162° were achieved on this membrane surface simultaneously, indicating its potential in the separation of phenol and water-soluble salt. Feed solution (500 mL) of 0.90 L/h and receiving solution (500 mL) of 1.26 L/h were investigated to be the optimum conditions for phenol separation, which corresponds to the employed Reynolds number of 14.6 and 20.5. During 108-h continuous separation for feed solution (2.0 g/L phenol, 10.0 g/L NaCl) under room temperature (20 °C), 42.6% of phenol was recycled in receiving solution with a salt rejection of 99.95%. Meanwhile, the mean phenol mass transfer coefficient (K ov ) was 6.7 × 10 -7  m s -1 . As a membrane-based process, though the permeated phenol increased with the increase of phenol concentration in feed solution, the phenol recovery ratio was determined by the membrane properties rather than the pollutant concentrations. Phenol was found to permeate this membrane via adsorption, diffusion and desorption, and therefore, the membrane fouling generated from pore blockage in other membrane separation processes was totally avoided. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sustainable biodegradation of phenol by immobilized Bacillus sp. SAS19 with porous carbonaceous gels as carriers.

PubMed

Ke, Qian; Zhang, Yunge; Wu, Xilin; Su, Xiaomei; Wang, Yuyang; Lin, Hongjun; Mei, Rongwu; Zhang, Yu; Hashmi, Muhammad Zaffar; Chen, Chongjun; Chen, Jianrong

2018-09-15

In this study, high-efficient phenol-degrading bacterium Bacillus sp. SAS19 which was isolated from activated sludge by resuscitation-promoting factor (Rpf) addition, were immobilized on porous carbonaceous gels (CGs) for phenol degradation. The phenol-degrading capabilities of free and immobilized Bacillus sp. SAS19 were evaluated under various initial phenol concentrations. The obtained results showed that phenol could be removed effectively by both free and immobilized Bacillus sp. SAS19. Furthermore, for degradation of phenol at high concentrations, long-term utilization and recycling were more readily achieved for immobilized bacteria as compared to free bacteria. Immobilized bacteria exhibited significant increase in phenol-degrading capabilities in the third cycle of recycling and reuse, which demonstrated 87.2% and 100% of phenol (1600 mg/L) degradation efficiency at 12 and 24 h, respectively. The present study revealed that immobilized Bacillus sp. SAS19 can be potentially used for enhanced treatment of synthetic phenol-laden wastewater. Copyright © 2018 Elsevier Ltd. All rights reserved.

A comprehensive evaluation of three microfluidic chemiluminescence methods for the determination of the total phenolic contents in fruit juices.

PubMed

Al Haddabi, Buthaina; Al Lawati, Haider A J; Suliman, FakhrEldin O

2017-01-01

Three recently reported microfluidic chemiluminescence (MF-CL) methods (based on reactions with acidic permanganate enhanced by formaldehyde (KMnO4-COH), acidic cerium (IV) and rhodamine B (Ce-RB), and acidic cerium (IV) and rhodamine 6G (Ce-R6G) enhanced by SDS) for the determination of the total phenolic content (TPC) in juices were critically evaluated in terms of their selectivity. The evaluation was carried out using 86 analytes, including 22 phenolic compounds (phenolic acids and polyphenols), 6 known non-phenolic antioxidants, 9 amino acids and a number of proteins, carbohydrates, nucleotide bases, inorganic salts and other compounds. Each method was sensitive toward phenolic compounds (PCs). However, the KMnO4-COH CL system showed a higher sensitivity toward phenolic acids and also responded to non-phenolic antioxidants. The other two systems showed higher sensitivity toward polyphenolic compounds than to phenolic acids and did not responded to all other compounds including non-phenolic antioxidants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bound Phenolics of Quinoa Seeds Released by Acid, Alkaline, and Enzymatic Treatments and Their Antioxidant and α-Glucosidase and Pancreatic Lipase Inhibitory Effects.

PubMed

Tang, Yao; Zhang, Bing; Li, Xihong; Chen, Peter X; Zhang, Hua; Liu, Ronghua; Tsao, Rong

2016-03-02

Unextractable phenolics from plant foods and their role in health benefits have become increasingly important. Meal residues of three quinoa seeds free of fat and extractable phenolics were subjected to acid, alkaline, and enzymatic hydrolyses. The total and individual phenolic compounds released were analyzed, and 19 phenolics, predominantly phenolic acids and several flavonoids, were identified. The concentration of bound phenolics was highest in black quinoa followed by red and white, regardless of the hydrolysis method. Higher phenolic contents also showed stronger antioxidant activities and inhibition of α-glucosidase and pancreatic lipase activities. Carbohydrases, that is, pectinase, xylanase and feruloyl esterase, which effectively liberated bound phenolics are known to be secreted by colonic bacteria, suggesting potential antioxidant and anti-inflammatory effects by these compounds in the large intestine during colonic fermentation. These results can also be applied to treat foods high in bound phenolics to enhance bioaccessibility.

Electrochemical removal of phenol from oil refinery wastewater.

PubMed

Abdelwahab, O; Amin, N K; El-Ashtoukhy, E-S Z

2009-04-30

This study explores the possibility of using electrocoagulation to remove phenol from oil refinery waste effluent using a cell with horizontally oriented aluminum cathode and a horizontal aluminum screen anode. The removal of phenol was investigated in terms of various parameters namely: pH, operating time, current density, initial phenol concentration and addition of NaCl. Removal of phenol during electrocoagulation was due to combined effect of sweep coagulation and adsorption. The results showed that, at high current density and solution pH 7, remarkable removal of 97% of phenol after 2h can be achieved. The rate of electrocoagulation was observed to increase as the phenol concentration decreases; the maximum removal rate was attained at 30 mg L(-1) phenol concentration. For a given current density using an array of closely packed Al screens as anode was found to be more effective than single screen anode, the percentage phenol removal was found to increase with increasing the number of screens per array. After 2h of electrocoagulation, 94.5% of initial phenol concentration was removed from the petroleum refinery wastewater. Energy consumption and aluminum Electrode consumption were calculated per gram of phenol removed. The present study shows that, electrocoagulation of phenol using aluminum electrodes is a promising process.

Lethal and sublethal effects of chlorine, phenol, and chlorine-phenol mixtures on the mud crab, Panopeus herbstii.

PubMed

Key, P B; Scott, G I

1986-11-01

The mud crab, Panopeus herbstii, was acutely exposed (96-hr) to chlorine-produced oxidants (CPO), phenol, and a CPO-phenolic mixture (1:1) to determine lethal and sublethal effects. The 96-hr (LC50) values were determined for each individual compound and mixture. Additionally, whole-animal respiration rates were measured following acute exposure to sublethal concentrations of each compound or mixture. Phenol uptake/depuration rates were measured in the phenol and CPO-phenol mixture concentrations. Results indicated 96-hr LC50 values of 1.06 mg/L for CPO (fiducial limits (FL) = 0.53-2.01 mg/L), 52.8 mg/L for phenol (FL = 45.6-64.5 mg/L), and 184.7 mg/L total toxicant units (TTU) for the CPO-phenol mixture (FL = 143.7-250.2 mg/L TTU). Statistical analysis indicated that the acute toxicity of the CPO-phenol mixture was less than additive. Sublethal studies indicated that only acute exposure to sublethal concentrations of CPO caused altered respiration rates. After 96-hr depuration, metabolic rates in all CPO-exposure crabs generally returned to control rates. Uptake/depuration rate studies indicated significantly lower phenol uptake rates in crabs exposed to the CPO-phenol mixture. These findings suggest that the less-than-additive toxicity of the CPO-phenol mixture may result from lowered uptake/depuration rate kinetics and indicate that the discharge of chlorinated-phenolic waste may not result in additive and/or synergistic interactions, but rather in less-than-additive effects on decapod aquatic species.

Inhibition of the acetoclastic methanogenic activity by phenol and alkyl phenols.

PubMed

Olguin-Lora, P; Puig-Grajales, L; Razo-Flores, E

2003-08-01

Chemical and petrochemical industries are important sources of aromatic pollutants. Petrochemical processes like caustic washing of middle distillates produce the spent caustic liquors highly concentrated in phenol and alkyl phenols. The anaerobic technology is considered a feasible strategy for petrochemical wastewater pre-treatment although high concentrations of phenol could limit its efficiency. The goal of this work was to determine the toxicity of both selected alkyl phenols and a synthetic "spent-caustic phenols mixture" on the acetoclastic Specific Methanogenic Activity (SMA) of unadapted and phenol-adapted granular sludge. Alkyl phenols were responsible for 50% (IC50) and 100% (IC100) inhibition of the SMA at concentrations ranging from 1.6 to 5.0 mM and from 4.1 to 27.5 mM, respectively, for un-adapted granular sludge. In the case of phenol-adapted granular sludge, the inhibitory concentrations ranged from 1.7 to 14.9 mM and from 4.0 to 83.0 for IC50 and IC100, respectively, highlighting the impact of sludge acclimation. The inhibition produced by 2-ethylphenol was more acute compared to phenol and was not reduced by the phenol acclimation process. The IC50 and IC100 values obtained for the synthetic "spent-caustic phenols mixture" were 9.5 mM and 88.4 mM, respectively. The inhibitory concentrations of phenol compounds were closely correlated with compound apolarity (log P), indicating that the lipophilic character of the tested compounds was responsible for their methanogenic toxicity. An inhibition model is confirmed to estimate the IC50 and IC100.

Determination of Radical Scavenging Activity and Total Phenols of Wine and Spices: A Randomized Study

PubMed Central

Lugemwa, Fulgentius Nelson; Snyder, Amanda L.; Shaikh, Koonj

2013-01-01

Thirty eight bottles of red wine (Carbanet Sauvignon) were randomly selected based on vintage, region, price, and age (number of months in a barrel). The total phenolic content of each wine was determined using Folin-Ciocalteau assay. The radical scavenging activity was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. Apart from a few bottles that exhibited above average radical scavenging activity and phenolic content, there was no good correlation of those two quantities with region, price or vintage. The average phenolic amount was 2874 mg/L. The lowest phenolic content was found to be 1648 mg/L for an eight dollar wine. Wine with the highest amount of phenol of 4495 mg/L was a 2007, nine dollar bottle from South America. High amount of phenols did not translate into high radical scavenging activity. Barrel-aging did not increase the amount of phenols or the radical scavenging activity of wine. In order to discover new and potent sources of antioxidants from plants, the following spices were studied: ginger, cilantro, cumin, anise, linden, eucalyptus, marjoram, oregano, sage, thyme and rosemary. Whole spices were crushed and extracted for 96 h at room temperature using a combination of ethyl acetate, ethyl alcohol and water in the ratio of 4.5:4.5:1 (v/v/v). The radical scavenging activity of extracts was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. The total phenolic content of each spice was also determined using the Folin-Ciocalteau assay. Eucalyptus was found to be the most potent antioxidant with an LC50 of 324.1 mg of phenol/L, followed by marjoram with an LC50 of 407.5 mg of phenol/L, and rosemary with an LC50 of 414.0 mg/L. The least potent antioxidants were ginger and cilantro with LC50 of 7604 mg/L of phenol and 7876 mg of phenol/L, respectively. PMID:26784340

A comparison of the toxicity and metabolism of phenol and chlorinated phenols by Lemna gibba, with special reference to 2,4,5-trichlorophenol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, H.A.; Barber, J.T.; Ensley, H.E.

1997-02-01

The toxicity of a series of chlorinated phenols, from phenol to pentachlorophenol, was determined using frond reproduction in aseptically grown Lemna gibba. The toxicities of the phenols tended to increase as the number of chlorine substituents on the phenol ring increased. The plants metabolized each of the phenols in the same manner producing metabolites that were more polar than their parent compounds. The metabolite for 2,4,5-trichlorophenol was isolated and identified by nuclear magnetic resonance spectroscopy and chemical ionization mass spectroscopy. The structural identity was confirmed by comparison with synthetic material as 2,4,5-trichlorophenyl-{beta}-D-glucopyranoside. These results, together with previously published results, suggestmore » that conjugation with D-glucose is a stereotypic response of duckweed to challenge by phenol and chlorinated phenols.« less

Influence of Protein-Phenolic Complex on the Antioxidant Capacity of Flaxseed (Linum usitatissimum L.) Products.

PubMed

Guimarães Drummond E Silva, Fernanda; Miralles, Beatriz; Hernández-Ledesma, Blanca; Amigo, Lourdes; Iglesias, Amadeu Hoshi; Reyes Reyes, Felix Guillermo; Netto, Flavia Maria

2017-02-01

The impact of the naturally present phenolic compounds and/or proteins on the antioxidant capacity of flaxseed products (phenolic fraction, protein concentrates, and hydrolysates) before and after simulated gastrointestinal digestion was studied. For that, whole and phenolic reduced products were assessed. Four glycosylated phenolic compounds (secoisolariciresinol and ferulic, p-coumaric, and caffeic acids) were identified in flaxseed products. Phenolic fraction exerts the highest antioxidant capacity that increased by alkaline hydrolysis and by simulated gastrointestinal digestion. The action of Alcalase and digestive enzymes resulted in an increase of the antioxidant capacity of whole and phenolic reduced products. Principal component analysis showed that proteinaceous samples act as antioxidant is by H + transfer, while those samples containing phenolic compounds exert their effects by both electron donation and H + transfer mechanisms. Protein/peptide-phenolic complexation, confirmed by fluorescence spectra, exerted a positive effect on the antioxidant capacity, mainly in protein concentrates.

Distribution and potential ecological risk of 50 phenolic compounds in three rivers in Tianjin, China.

PubMed

Zhong, Wenjue; Wang, Donghong; Wang, Zijian

2018-04-01

Phenolic compounds widely exist in the surface water of many countries; however, few studies have simultaneously analyzed and evaluated broad-spectrum phenolic compounds in various components of the water environment. Therefore this study analyzed the distribution and potential ecological risk of 50 phenolic compounds in the surface water, sediment and suspended particulate matter of three important rivers in Tianjin, the main heavy industry city with high pollution in China. The qualitative results show that phenolic pollution existed extensively in the three rivers and the kinds of phenolic compounds in the water were relatively higher than in both sediment and suspended particulate matter. The quantitative results show that the phenolic pollution in the wet-season samples was serious than dry-season samples. Meanwhile, total concentrations of phenolic compounds in three components from the Dagu Drainage River (DDR) were all much higher than those in the Beitang Drainage River (BDR) and Yongdingxin River (YDXR). The highest total concentrations of phenolic compounds in three components all appeared in wet-season samples in DDR, and the highest total concentration was 1354 μg/L in surface water, 719 μg/kg dw in suspended particulate matter and 2937 μg/kg dw in sediment, respectively. The ecological risk of phenolic compounds in surface water was evaluated using the quotient method, and phenolic compounds with risk quotient (RQ) > 1 (RQ > 0.3 for YDXR) were identified as priority pollutants. Five kinds of phenolic compounds were identified as priority phenolic compounds in BDR, and the order of risk was 2-cresol > 2,4-xylenol > 2-sec-butylphenol > 2-naphthol > 3-cresol. Six kinds of phenolic compounds were identified as priority phenolic compounds in DDR, and the order of risk was 2-naphthol > p-chloro-m-xylenol > 4-cresol > 3-cresol > 2,4-xylenol > 2,3,6-Trimethylphenol. In YDXR, only phenol, 2-naphthol and 2,4-xylenol were identified as priority phenolic compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inhibitory potentials of phenolic-rich extracts from Bridelia ferruginea on two key carbohydrate-metabolizing enzymes and Fe2+-induced pancreatic oxidative stress.

PubMed

Afolabi, Olakunle Bamikole; Oloyede, Omotade Ibidun; Agunbiade, Shadrack Oludare

2018-05-01

The current study was designed to evaluate the various antioxidant potentials and inhibitory effects of phenolic-rich leaf extracts of Bridelia ferruginea (BF) on the in vitro activities of some key enzymes involved in the metabolism of carbohydrates. In this study, BF leaf free and bound phenolic-rich extracts were used. We quantified total phenolic and flavonoid contents, and evaluated several antioxidant activities using assays for ferric reducing antioxidant power, total antioxidant activity (phosphomolybdenum reducing ability), 1,1-diphenyl-2-picrylhydrazyl and thiobarbituric acid reactive species. Also, extracts were tested for their ability to inhibit α-amylase and α-glucosidase activity. The total phenolic and total flavonoid contents in the free phenolic extract of BF were significantly greater than in the bound phenolic extract. Also, all the antioxidant activities considered were significantly greater in the free phenolic extract than in the bound phenolic extract. In the same vein, the free phenolic-rich extract had a significantly higher percentage inhibition against α-glucosidase activity (IC 50  = 28.5 µg/mL) than the bound phenolic extract (IC 50  = 340.0 µg/mL). On the contrary, the free phenolic extract (IC 50  = 210.0 µg/mL) had significantly lower inhibition against α-amylase than the bound phenolic-rich extract (IC 50  = 190.0 µg/mL). The phenolic-rich extracts of BF leaves showed antioxidant potentials and inhibited two key carbohydrate-metabolizing enzymes in vitro. Copyright © 2018 Shanghai Changhai Hospital. Published by Elsevier B.V. All rights reserved.

Investigation on the reaction of phenolic pollutions to mono-rhamnolipid micelles using MEUF.

PubMed

Liu, Zhifeng; Yu, Mingda; Zeng, Guangming; Li, Min; Zhang, Jiachao; Zhong, Hua; Liu, Yang; Shao, Binbin; Li, Zhigang; Wang, Zhiquan; Liu, Guansheng; Yang, Xin

2017-01-01

Micellar-enhanced ultrafiltration (MEUF) processes of resorcinol, phenol, and 1-Naphthol with rhamnolipid as an anionic biosurfactant were investigated using polysulfone membrane. The effects of retentate/permeate concentration of phenolic pollutants (C R /C P ), distribution coefficient of phenolic pollutions (D), concentration ratios of phenolic pollutions (α P ) and rhamnolipids (α R ) and adsorption capacity of the membrane (N m ) were studied by operating pressure, pH condition, feed surfactant, and phenolic pollution concentrations. Results showed that C R (with pH) increased and ranked in the following order: resorcinol > phenol > 1-Naphthol, which is same with C R (with pressure), C R (with surfactant), C R /C P (with pollution), α, P and D, while C P (with pH), C P (with pressure), and C P (with surfactant) ranked in the reverse order. The operating pressure increased the solubility of phenolic from 0 to 0.1 MPa and then decreased slowly above 0.1 MPa. The concentration ratio of rhamnolipid was nearly at 2.0 and that of phenolic pollution was slightly above 1.0. D of phenolic pollutants reached the maximum at phenolic pollution concentration of 0.1 mM and the feed rhamnolipid concentration at 1 CMC. Moreover, zeta potential in feed stream and retentate stream and membrane adsorption of phenolic pollutions were firstly investigated in this article; the magnitudes of zeta potential with the feed stream of three phenolic pollutions were nearly the same and slightly lower than those with the retentate stream. The adsorption capacity of the membrane (N m ) was calculated and compared to the former research, which showed that rhamnolipid significantly decreases the membrane adsorption of phenolic pollutions at a relatively lower concentration. It was implied that rhamnolipid can be substituted for chemical surfactants.

Isolation and characterization of phenol degrading bacterium strain Bacillus thuringiensis J20 from olive waste in Palestine.

PubMed

Ereqat, Suheir I; Abdelkader, Ahmad A; Nasereddin, Abedelmajeed F; Al-Jawabreh, Amer O; Zaid, Taher M; Letnik, Ilya; Abdeen, Ziad A

2018-01-02

This study aimed at isolation of phenol degrading bacteria from olive mill wastes in Palestine. The efficiency of phenol removal and factors affecting phenol degradation were investigated. A bacterial strain (J20) was isolated from solid olive mill waste and identified as Bacillus thuringiensis based on standard morphological, biochemical characteristics and 16SrRNA sequence analysis. The strain was able to grow in a phenol concentration of 700 mg/L as the sole carbon and energy source. The culture conditions showed a significant impact on the ability of these cells to remove phenol. This strain exhibited optimum phenol degradation performance at pH 6.57 and 30 °C . Under the optimized conditions, this strain could degrade 88.6% of phenol (700 mg/L) within 96 h when the initial cell density was OD 600 0.2. However, the degradation efficiency could be improved from about 88% to nearly 99% by increasing the cell density. Immobilization of J20 was carried out using 4% sodium alginate. Phenol degradation efficiency of the immobilized cells of J20 was higher than that of the free cells, 100% versus 88.6% of 700 mg/L of phenol in 120 h, indicating the improved tolerance of the immobilized cells toward phenol toxicity. The J20 was used in detoxifying crude OMWW, phenolic compounds levels were reduced by 61% compared to untreated OMWW after five days of treatment. Hence, B. thuringiensis-J20 can be effectively used for bioremediation of phenol-contaminated sites in Palestine. These findings may lead to new biotechnological applications for the degradation of phenol, related to olive oil production.

Biodegradation of phenol in synthetic and industrial wastewater by Rhodococcus erythropolis UPV-1 immobilized in an air-stirred reactor with clarifier.

PubMed

Prieto, M B; Hidalgo, A; Rodríguez-Fernández, C; Serra, J L; Llama, M J

2002-05-01

Phenol biodegradation by suspended and immobilized cells of Rhodococcus erythropolis UPV-1 was studied in discontinuous and continuous mode under optimum culture conditions. Phenol-acclimated cells were adsorbed on diatomaceous earth, where they grew actively forming a biofilm of short filaments. Immobilization protected cells against phenol and resulted in a remarkable enhancement of their respiratory activity and a shorter lag phase preceding active phenol degradation. Under optimum operation conditions in a laboratory-scale air-stirred reactor, the immobilized cells were able to completely degrade phenol in synthetic wastewater at a volumetric productivity of 11.5 kg phenol m(-3) day(-1). Phenol biodegradation was also tested in two different industrial wastewaters (WW1 and WW2) obtained from local resin manufacturing companies, which contained both phenols and formaldehyde. In this case, after wastewater conditioning (i.e., dilution, pH, nitrogen and phosphorous sources and micronutrient amendments) the immobilized cells were able to completely remove the formaldehyde present in both waters. Moreover, they biodegraded phenols completely at a rate of 0.5 kg phenol m(-3) day(-1) in the case of WW1 and partially (but at concentrations lower than 50 mg l(-1)) at 0.1 and 1.0 kg phenol m(-3) day(-1) in the cases of WW2 and WW1, respectively.

Directional liquefaction of biomass for phenolic compounds and in situ hydrodeoxygenation upgrading of phenolics using bifunctional catalysts

Treesearch

Junfeng Feng; Chung-yun Hse; Kui Wang; Zhongzhi Yang; Jianchun Jiang; Junming Xu

2017-01-01

Phenolic compounds derived from biomass are important feedstocks for the sustainable production of hydrocarbon biofuels. Hydrodeoxygenation is an effective process to remove oxygen-containing functionalities in phenolic compounds. This paper reported a simple method for producing hydrocarbons by liquefying biomass and upgrading liquefied products. Three phenolic...

Selective defunctionalization by TiO2 of monomeric phenolics from lignin pyrolysis into simple phenols.

PubMed

Mante, Ofei D; Rodriguez, Jose A; Babu, Suresh P

2013-11-01

This study is focused on defunctionalizing monomeric phenolics from lignin into simple phenols for applications such as phenol/formaldehyde resins, epoxidized novolacs, adhesives and binders. Towards this goal, Titanium dioxide (TiO2) was used to selectively remove hydroxyl, methoxy, carbonyl and carboxyl functionalities from the monomeric phenolic compounds from lignin to produce mainly phenol, cresols and xylenols. The results showed that anatase TiO2 was more selective and active compared to rutile TiO2. Catechols were found to be the most reactive phenolics and 4-ethylguaiacol the least reactive with anatase TiO2. An overall conversion of about 87% of the phenolics was achieved at 550°C with a catalyst-to-feed ratio of 5 w/w. Over 97% conversion of phenolics is achievable at moderate temperatures (550°C or ≤ 600°C) and a moderate catalyst-to-feed ratio of 6.5:1. The reactivity of catechols on TiO2 suggests that titania is a promising catalyst in the removal of hydroxyl moiety. Published by Elsevier Ltd.

Transition of phenolics and cyanogenic glycosides from apricot and cherry fruit kernels into liqueur.

PubMed

Senica, Mateja; Stampar, Franci; Veberic, Robert; Mikulic-Petkovsek, Maja

2016-07-15

Popular liqueurs made from apricot/cherry pits were evaluated in terms of their phenolic composition and occurrence of cyanogenic glycosides (CGG). Analyses consisted of detailed phenolic and cyanogenic profiles of cherry and apricot seeds as well as beverages prepared from crushed kernels. Phenolic groups and cyanogenic glycosides were analyzed with the aid of high-performance liquid chromatography (HPLC) and mass spectrophotometry (MS). Lower levels of cyanogenic glycosides and phenolics have been quantified in liqueurs compared to fruit kernels. During fruit pits steeping in the alcohol, the phenolics/cyanogenic glycosides ratio increased and at the end of beverage manufacturing process higher levels of total analyzed phenolics were detected compared to cyanogenic glycosides (apricot liqueur: 38.79 μg CGG per ml and 50.57 μg phenolics per ml; cherry liqueur 16.08 μg CGG per ml and 27.73 μg phenolics per ml). Although higher levels of phenolics are characteristic for liqueurs made from apricot and cherry pits these beverages nevertheless contain considerable amounts of cyanogenic glycosides. Copyright © 2016 Elsevier Ltd. All rights reserved.

Soybean phenolic-rich extracts inhibit key-enzymes linked to type 2 diabetes (α-amylase and α-glucosidase) and hypertension (angiotensin I converting enzyme) in vitro.

PubMed

Ademiluyi, Adedayo O; Oboh, Ganiyu

2013-03-01

This study sought to assess the inhibitory activities of phenolic-rich extracts from soybean on α-amylase, α-glucosidase and angiotensin I converting enzyme (ACE) activities in vitro. The free phenolic extract of the soybean was obtained by extraction with 80% acetone, while that of the bound phenolic extract was done by extracting the alkaline and acid hydrolyzed residue with ethyl acetate. The inhibitory action of these extracts on the enzymes activity as well as their antioxidant properties was assessed. Both phenolic-rich extracts inhibited α-amylase, α-glucosidase and ACE enzyme activities in a dose dependent pattern. However, the bound phenolic extract exhibited significantly (P < 0.05) higher α-amylase and ACE inhibition while the free phenolic extract had significantly (P < 0.05) higher α-glucosidase inhibitory activity. Nevertheless, the free phenolic extract had higher α-glucosidase inhibitory activity when compared to that of α-amylase; this property confer an advantage on soybean phenolic-rich extracts over commercial antidiabetic drugs with little or no side effect. And inhibition of ACE suggests the antihypertension potential of soybean phenolic-rich extracts. Furthermore, the enzyme inhibitory activities of the phenolic-rich extracts were not associated with their phenolic content. Therefore, phenolic-rich extracts of soybean could inhibit key-enzyme linked to type 2 diabetes (α-amylase and α-glucosidase) and hypertension (ACE) and thus could explain in part the mechanism by which soybean renders these health promoting effect. Copyright © 2011 Elsevier GmbH. All rights reserved.

Accumulation of Phenolic Compounds and Expression Profiles of Phenolic Acid Biosynthesis-Related Genes in Developing Grains of White, Purple, and Red Wheat.

PubMed

Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai

2016-01-01

Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation.

Accumulation of Phenolic Compounds and Expression Profiles of Phenolic Acid Biosynthesis-Related Genes in Developing Grains of White, Purple, and Red Wheat

PubMed Central

Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai

2016-01-01

Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation. PMID:27148345

Phenolics and antioxidant capacity of table grape (Vitis vinifera L.) cultivars grown in Chile.

PubMed

Lutz, Mariane; Jorquera, Katterin; Cancino, Beatriz; Ruby, Rene; Henriquez, Carolina

2011-09-01

Grapes (Vitis vinifera L.) possess health-promoting effects attributed to their supply of a wide variety of bioactive phenolics. Juice and skin fractions of 4 varieties of table grapes: Red Globe, Crimson Seedless, Autumn Royal, and Ribier were prepared to determine and compare their total phenolics content, antioxidant capacity (DPPH, FRAP, and ORAC), anthocyanins, and specific phenolics (caffeic acid, gallic acid, resveratrol, and catechin) content, since a series of positive health benefits are expected from the intake of any of these fractions. Higher amounts of total phenolics and antioxidant capacity were observed in the skin fractions (P < 0.05). Blue grapes (Autumn Royal and Ribier) exhibited higher phenolics content and antioxidant capacity (P < 0.05) than red grapes. The most abundant phenolic compound observed was catechin (P < 0.05). Significant correlations between the antioxidant capacity and total phenolics were observed in grape juice and skin fractions. Autumn Royal juice provides a very high amount of phenolics, anthocyanins, and exhibits the highest antioxidant capacity, offering the best health promoting properties compared with the other grape varieties studied. Grapes possess health-promoting effects attributed to their supply of a wide variety of bioactive phenolics. Grape juice made with blue grapes (Autumn Royal, Ribier) exhibit higher phenolics content and antioxidant capacity than juice elaborated with red grapes (Red Globe, Crimson Seedless). The skin is a good source of phenolics and has a high antioxidant capacity. Specific health-promoting phenolics are more abundant in blue grapes, mainly in their skin fraction, which should not be discarded. © 2011 Institute of Food Technologists®

VUV/UV light inducing accelerated phenol degradation with a low electric input† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6ra26043h Click here for additional data file.

PubMed Central

Li, Mengkai; Wen, Dong

2017-01-01

This study presents the first evidence for the accelerated degradation of phenol by Fenton's reagent in a mini-fluidic VUV/UV photoreaction system (MVPS). A low-pressure mercury lamp used in the MVPS led to a complete degradation of phenol within 4–6 min. The HO˙ and HO2˙ originating from both Fenton's reagent and VUV photolysis of water were identified with suitable radical scavengers. The effects of initial concentrations of phenol, H2O2 and Fe3+ as well as solution pH on phenol degradation kinetics were examined. Increasing the initial phenol concentration slowed down the phenol degradation, whereas increasing the initial H2O2 or Fe3+ concentration accelerated the phenol degradation. The optimal solution pH was 3.7. At both 254 and 185 nm, increasing phenol concentration enhanced its absorption for the incident photons. The reaction mechanism for the degradation of phenol was suggested consistent with the results obtained. This study indicates that the VUV/UV photo-Fenton process has potential applications in the treatment of industrial wastewater containing phenol and related aromatic pollutants. PMID:28496972

Changes of phenolic profiles and antioxidant activity in canaryseed (Phalaris canariensis L.) during germination.

PubMed

Chen, Zhijie; Yu, Lilei; Wang, Xinkun; Gu, Zhenxin; Beta, Trust

2016-03-01

Canaryseed is an important cereal crop in western Canada. The changes of the total phenolic content (TPC), antioxidant activities, phenolic acid profiles (free and bound) of canaryseed during germination were investigated in the present study. The growth properties also were investigated. Fresh weight, shoot length and root length increased, whereas dry mass of canaryseed decreased during germination. A 22.3% loss of dry matter was observed at 120h of germination. The total phenolic content and antioxidant activities of free and bound extracts showed a general trend of germinated seeds>raw seeds>soaked seeds. Free, bound and total phenolic content significantly increased 1042%, 120% and 741% at the end of germination as compared to raw seeds (p<0.05). DPPH, ABTS and ORAC assays were employed to evaluate the antioxidant activity of canaryseed. There were high correlations between total phenolic content and antioxidant activities. TPC and ORAC values showed the highest correlation (r=0.9984). Six phenolic acids in free phenolic extracts and seven phenolic acids in bound phenolic extracts were detected, respectively. Bound ferulic acid, the dominant phenolic acid in canaryseed, significantly increased during germination (p<0.05). Study showed that germination provided a new approach to further develop canaryseed as a functional food for human consumption. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phenolic profiles and antioxidant activity of Turkish Tombul hazelnut samples (natural, roasted, and roasted hazelnut skin).

PubMed

Pelvan, Ebru; Olgun, Elmas Öktem; Karadağ, Ayşe; Alasalvar, Cesarettin

2018-04-01

The phenolic profiles and antioxidant status of hazelnut samples [natural (raw) hazelnut, roasted hazelnut, and roasted hazelnut skin] were compared. Free and bound (ester-linked and glycoside-linked) phenolic acids were examined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Comprehensive identification of phenolics was carried out using Q-exactive hybrid quadrupole-orbitrap mass spectrometer (Q-OT-MS). Samples were also assessed for their total phenolics and antioxidant activities using three different assays. Ten free and bound phenolic acids were quantified in hazelnut samples. Roasted hazelnut skin contained the highest content of total phenolic acids, followed by natural and roasted hazelnuts. The majority of phenolic acids were present in the bound form. Using a Q-OT-MS, 22 compounds were tentatively identified, 16 of which were identified for the first time in hazelnut samples. The newly identified compounds consisted of flavonoids, phenolic acids and related compounds, hydrolysable tannins and related compounds, and other phenolics. Three antioxidant assays demonstrated similar trends that roasted hazelnut skin rendered the highest activity. The present work suggests that roasted hazelnut skin is a rich source of phenolics and can be considered as a value-added co-product for use as functional food ingredient and antioxidant. Copyright © 2017 Elsevier Ltd. All rights reserved.

Predicting the hydroxymethylation rate of phenols with formaldehyde by molecular orbital calculation.

Treesearch

Tohru Mitsunaga; Anthony H. Conner; Charles G. Hill

2002-01-01

The rates (k) of hydroxymethylation of phenol, resorcinol. phloroglucinol, and several methylphenols in diluted 10% dimethylformamide aqueous alkaline solution were calculated based on the consumption of phenols and formaldehyde. The k values of phloroglucinol and resorcinol relative to that of phenol were about 62000 and 1200 times, respectively. The phenols that have...

Wine phenolics.

PubMed

Waterhouse, Andrew L

2002-05-01

Wine contains many phenolic substances, most of which originate in the grape berry. The phenolics have a number of important functions in wine, affecting the tastes of bitterness and astringency, especially in red wine. Second, the color of red wine is caused by phenolics. Third, the phenolics are the key wine preservative and the basis of long aging. Lastly, since phenolics oxidize readily, they are the component that suffers owing to oxidation and the substance that turns brown in wine (and other foods) when exposed to air. Wine phenolics include the non-flavonoids: hydroxycinnamates, hydroxybenzoates and the stilbenes; plus the flavonoids: flavan-3-ols, the flavonols, and the anthocyanins. While polymeric condensed tannins and pigmented tannins constitute the majority of wine phenolics, their large size precludes absorption and thus they are not likely to have many health effects (except, perhaps, in the gut). The total amount of phenols found in a glass of red wine is on the order of 200 mg versus about 40 mg in a glass of white wine.

Development and UFLC-MS/MS Characterization of a Product-Specific Standard for Phenolic Quantification of Maple-Derived Foods.

PubMed

Liu, Yongqiang; Ma, Hang; Seeram, Navindra P

2016-05-04

The phenolic contents of plant foods are commonly quantified by the Folin-Ciocalteu assay based on gallic acid equivalents (GAEs). However, this may lead to inaccuracies because gallic acid is not always representative of the structural heterogeneity of plant phenolics. Therefore, product-specific standards have been developed for the phenolic quantification of several foods. Currently, maple-derived foods (syrup, sugar, sap/water, and extracts) are quantified for phenolic contents based on GAEs. Because lignans are the predominant phenolics present in maple, herein, a maple phenolic lignan-enriched standard (MaPLES) was purified (by chromatography) and characterized (by UFLC-MS/MS with lignans previously isolated from maple syrup). Using MaPLES and secoisolariciresinol (a commercially available lignan), the phenolic contents of the maple-derived foods increased 3-fold compared to GAEs. Therefore, lignan-based standards are more appropriate for phenolic quantification of maple-derived foods versus GAEs. Also, MaPLES can be utilized for the authentication and detection of fake label claims on maple products.

An adsorption-release-biodegradation system for simultaneous biodegradation of phenol and ammonium in phenol-rich wastewater.

PubMed

Wang, Ying; Chen, Hu; Liu, Yu-Xiang; Ren, Rui-Peng; Lv, Yong-Kang

2016-07-01

The feasibility of simultaneous biodegradation of phenol and ammonium in phenol-rich wastewater was evaluated in a reusable system, which contained macroporous adsorption resin and Alcaligenes faecalis strain WY-01. In the system, up to 6000mg/L phenol could be completely degraded by WY-01; meanwhile, 99.03±3.95% of ammonium was removed from the initial concentration of 384mg/L. This is the first study to show the capability of single strain in simultaneous removal of ammonium and phenol in wastewater containing such high concentrations of phenol. Moreover, the resin was regenerated during the biodegradation process without any additional manipulations, indicating the system was reusable. Furthermore, enzyme assay, gene expression patterns, HPLC-MS and gas chromatography analysis confirmed that phenol biodegradation accompanied with aerobic nitrifier denitrification process. Results imply that the reusable system provides a novel strategy for more efficient biodegradation of phenol and ammonium contained in some particular industrial wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of phenol on the mycelial growth and fructification in some of basidiomycetous fungi.

PubMed

Upadhyay, R C; Hofrichter, M

1993-01-01

Cometabolic growth studies with phenol were undertaken to screen 32 strains of white and brown rot fungi. All the cultures studied grew well up to 4 mM of phenol on Czapekdox agar except Agaricus bisporus (white button mushroom) and Pleurotus cystidiosus. Most of them could grow even up to 6 mM of phenol. Phenol induced a brown pigmentation of the culture medium. P. flabellatus and P. pulmonarius metabolized 67 and 64 mg/l phenol in 10 days. Studies have indicated that phenol (0.1 to 1.0 mM) incorporated in malt-extract agar has no inhibitory effect on fruitbody formation. Preliminary studies indicate that soaking of wheat straw with phenol solution up to 1600 mg/l give better mycelial growth and fructification of P. cornucopiae, P. ostreatus Z-15 and Calocybe indica than water soaked. Soaking of wheat straw in phenol inhibited the growth of common competitor weed fungi like Stachybotrys sp. and Coprinus sp.

Pulse seed germination improves antioxidative activity of phenolic compounds in stripped soybean oil-in-water emulsions.

PubMed

Xu, Minwei; Jin, Zhao; Peckrul, Allen; Chen, Bingcan

2018-06-01

The purpose of this study was to investigate antioxidative activity of phenolic compounds extracted from germinated pulse seed including chickpeas, lentils and yellow peas. Phenolic compounds were extracted at different germination time and total phenolic content was examined by Folin Ciocalteu's reaction. Antioxidative activity of extracts was characterized by in vitro assay including 2, 2-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH), oxygen radical absorbance capacity (ORAC), iron-binding assay, and in stripped soybean oil-in-water emulsions. The results suggested that germination time is critical for phenolic compounds production. The form variation of phenolic compounds influenced the antioxidative activity of phenolic compounds both in vitro assay and in emulsion systems. Soluble bound phenolic compounds showed higher antioxidative ability in emulsion system with the order of chickpea > yellow pea > lentil. On the basis of these results, soluble bound phenolic compounds may be considered as a promising natural antioxidant to prevent lipid oxidation in foods. Copyright © 2018 Elsevier Ltd. All rights reserved.

Phenolic Polymer Solvation in Water and Ethylene Glycol, II: Ab Initio Computations.

PubMed

Bauschlicher, Charles W; Bucholz, Eric W; Haskins, Justin B; Monk, Joshua D; Lawson, John W

2017-04-06

Ab initio techniques are used to study the interaction of ethylene glycol and water with a phenolic polymer. The water bonds more strongly with the phenolic OH than with the ring. The phenolic OH groups can form hydrogen bonds between themselves. For more than one water molecule, there is a competition between water-water and water-phenolic interactions. Ethylene glycol shows the same effects as those of water, but the potential energy surface is further complicated by CH 2 -phenolic interactions, different conformers of ethylene glycol, and two OH groups on each molecule. Thus, the ethylene glycol-phenolic potential is more complicated than the water-phenolic potential. The results of the ab initio calculations are compared to those obtained using a force field. These calibration studies show that the water system is easier to describe than the ethylene glycol system. The calibration studies confirm the reliability of force fields used in our companion molecular dynamics study of a phenolic polymer in water and ethylene solutions.

Recycling of phenolic compounds in Borneo's tropical peat swamp forests.

PubMed

Yule, Catherine M; Lim, Yau Yan; Lim, Tse Yuen

2018-02-07

Tropical peat swamp forests (TPSF) are globally significant carbon stores, sequestering carbon mainly as phenolic polymers and phenolic compounds (particularly as lignin and its derivatives) in peat layers, in plants, and in the acidic blackwaters. Previous studies show that TPSF plants have particularly high levels of phenolic compounds which inhibit the decomposition of organic matter and thus promote peat accumulation. The studies of phenolic compounds are thus crucial to further understand how TPSF function with respect to carbon sequestration. Here we present a study of cycling of phenolic compounds in five forests in Borneo differing in flooding and acidity, leaching of phenolic compounds from senescent Macaranga pruinosa leaves, and absorption of phenolics by M. pruinosa seedlings. The results of the study show that total phenolic content (TPC) in soil and leaves of three species of Macaranga were highest in TPSF followed by freshwater swamp forest and flooded limestone forest, then dry land sites. Highest TPC values were associated with acidity (in TPSF) and waterlogging (in flooded forests). Moreover, phenolic compounds are rapidly leached from fallen senescent leaves, and could be reabsorbed by tree roots and converted into more complex phenolics within the leaves. Extreme conditions-waterlogging and acidity-may facilitate uptake and synthesis of protective phenolic compounds which are essential for impeded decomposition of organic matter in TPSF. Conversely, the ongoing drainage and degradation of TPSF, particularly for conversion to oil palm plantations, reverses the conditions necessary for peat accretion and carbon sequestration.

Comparison of adsorption and photo-Fenton processes for phenol and paracetamol removing from aqueous solutions: Single and binary systems

NASA Astrophysics Data System (ADS)

Rad, Leila Roshanfekr; Haririan, Ismaeil; Divsar, Faten

2015-02-01

In the present study, adsorption and photo-Fenton processes have been compared for the removal of phenol and paracetamol from aqueous solutions in a single and binary systems. NaX nanozeolites and cobalt ferrite nanoparticles were used during adsorption and photo-Fenton processes, respectively. Both nanoparticles were synthesized using microwave heating method. The synthesized nanoparticles were characterized using powder X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analysis. Based on results, more than 99% removing percentages of phenol and paracetamol were obtained during photo-Fenton process at initial concentrations of 10, 20, 50, 100 and 200 mg/L of phenol and paracetamol. Moreover, the complete removing of phenol and paracetamol was only achieved at lower initial concentrations than 10 mg/L for phenol and paracetamol during adsorption process. The results showed a significant dependence of the phenol and paracetamol removing on the initial concentrations of phenol and paracetamol for selection of process. The photo-Fenton process could be considered an alternative method in higher initial concentrations of phenol and paracetamol. However, the adsorption process due to economical issue was preferred for phenol and paracetamol removing at lower initial concentrations. The kinetic data of photo-Fenton and adsorption processes were well described using first-order and pseudo-second-order kinetic models. The results of phenol and paracetamol removing in a binary system confirmed the obtained results of single removing of phenol and paracetamol in selection of process.

Hybridized Thermoplastic Aramids: Enabling Material Technology For Future Force Headgear

DTIC Science & Technology

2006-11-01

keeping the complete helmet weight the same. Design Material Rolled steel Hadfield Steel Kevlar 29/PVB Phenolic Kevlar 129/PVB...Material Rolled steel Hadfield Steel Kevlar 29/PVB Phenolic Kevlar 129/PVB phenolic Thermoplastic aramid Twaron/PVB phenolic ...Deflection RESULTS Improved Fiber, Fiber Architecture, and Matrix Materials Enable Performance Enhancement PASGT: 19 Ply S735 Kevlar with PVB Phenolic

Phenolic metabolites in carnivorous plants: Inter-specific comparison and physiological studies.

PubMed

Kováčik, Jozef; Klejdus, Bořivoj; Repčáková, Klára

2012-03-01

Despite intensive phytochemical research, data related to the accumulation of phenols in carnivorous plants include mainly qualitative reports. We have quantified phenolic metabolites in three species: Drosera capensis, Dionaea muscipula and Nepenthes anamensis in the "leaf" (assimilatory part) and the "trap" (digestive part). For comparison, commercial green tea was analysed. Phenylalanine ammonia-lyase (PAL) activities in Dionaea and Nepenthes were higher in the trap than in the leaf while the opposite was found in Drosera. Soluble phenols and majority of phenolic acids were mainly accumulated in the trap among species. Flavonoids were abundant in Drosera and Dionaea traps but not in Nepenthes. Phenolic acids were preferentially accumulated in a glycosidically-bound form and gallic acid was the main metabolite. Green tea contained more soluble phenols and phenolic acids but less quercetin. In vitro experiments with Drosera spathulata revealed that nitrogen deficiency enhances PAL activity, accumulation of phenols and sugars while PAL inhibitor (2-aminoindane-2-phosphonic acid) depleted phenols and some amino acids (but free phenylalanine and sugars were elevated). Possible explanations in physiological, biochemical and ecological context are discussed. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Plant phenolic compounds and oxidative stress: integrated signals in fungal-plant interactions.

PubMed

Shalaby, Samer; Horwitz, Benjamin A

2015-08-01

Upon invasion of a host, fungal pathogens are exposed to a variety of stresses. Plants release reactive oxygen species, and mount a variety of preformed and induced chemical defenses. Phenolic compounds are one example: they are ubiquitous in plants, and an invading pathogen encounters them already at the leaf surface, or for soil-borne pathogens, in the rhizosphere. Phenolic and related aromatic compounds show varying degrees of toxicity to cells. Some compounds are quite readily metabolized, and others less so. It was known already from classical studies that phenolic substrates induce the expression of the enzymes for their degradation. Recently, the ability to degrade phenolics was shown to be a virulence factor. Conversely, phenolic compounds can increase the effectiveness of antifungals. Phenolics are known antioxidants, yet they have been shown to elicit cellular responses that would usually be triggered to counter oxidant stress. Here, we review the evidence for a connection between the fungal response to phenolics as small-molecule signals, and the response to oxidants. The connections proposed here should enable genetic screens to identify specific fungal receptors for plant phenolics. Furthermore, understanding how the pathogen detects plant phenolic compounds as a stress signal may facilitate new antifungal strategies.

Influence of Various Phenolic Compounds on Properties of Gelatin Film Prepared from Horse Mackerel Trachurus japonicus Scales.

PubMed

Le, Thuy; Maki, Hiroki; Okazaki, Emiko; Osako, Kazufumi; Takahashi, Kigen

2018-06-15

Influence of various phenolic compounds on physical properties and antioxidant activity of gelatin film from horse mackerel Trachurus japonicus scales was investigated. Tensile strength (TS) of the film was enhanced whereas elongation at break was declined by adding 1% to 5% phenolic compounds. Rutin was the most effective to improve the TS compared to the other tested phenolic compounds including ferulic acid, caffeic acid, gallic acid, and catechin. Gelatin films with the phenolic compounds showed the excellent UV barrier properties. FTIR spectra exhibited that wavenumber of amide-A band of films decreased with formation of hydrogen bonding between amino groups of gelatin and hydroxyl groups of the phenolic compounds. Gelatin film incorporated with rutin which has the largest number of hydroxyl groups among the tested compounds demonstrated the lowest wavenumber for the amide-A peak. It is indicated that hydroxyl groups contained in the phenolic compounds contribute to formation of hydrogen bonds involved in improvement of the mechanical properties of the films. The incorporation of the phenolic compounds with gelatin films also led to the increasing of total phenolic contents and DPPH radical scavenging activities. Thus, it is concluded that phenolic compounds can promote the quality of gelatin film. Properties of gelatin film derived from horse mackerel scales can be improved by adding of phenolic compounds. Phenolic compounds containing a large number of hydroxyl groups should be selected to enhance physical properties of the gelatin film. A biodegradable film prepared from horse mackerel gelatin incorporated with phenolic compounds, which has good physical properties and antioxidant properties, can solve environmental problems caused by synthetic plastic materials. © 2018 Institute of Food Technologists®.

[Effect of soil phenolic acids on soil microbe of coal-mining depressed land after afforestation restoration by different tree species].

PubMed

Ji, Li; Yang, Li Xue

2017-12-01

Phenolic acids are one of the most important factors that influence microbial community structure. Investigating the dynamic changes of phenolic acids and their relationship with the microbial community structure in plantation soils with different tree species could contribute to better understanding and revealing the mechanisms of microbial community changes under afforestation restoration in coal-mining subsidence areas. In this study, plantations of three conifer and one deciduous species (Pinus koraiensis, Larix gmelinii, Pinus sylvestris var. mongolica, and Populus ussuriensis) were established on abandoned coal-mining subsidence areas in Baoshan District, Shuangyashan City. The contents of soil phenols, 11 types of phenolic acids, and microbial communities in all plots were determined. The results showed that the contents of soil complex phenol in plantations were significantly higher than that of abandoned land overall. Specifically, soils in larch and poplar plantations had higher contents of complex phenol, while soils in larch and Korean pine plantations had greater contents of total phenol. Moreover, soil in the P. koraiensis plantation had a higher content of water-soluble phenol compared with abandoned lands. The determination of 11 phenolic acids indicated that the contents of ferulic acid, abietic acid, β-sitosterol, oleanolic acid, shikimic acid, linoleic acid, and stearic acid were higher in plantation soils. Although soil phenol contents were not related with soil microbial biomass, the individual phenolic acids showed a significant relationship with soil microbes. Ferulic acid, abietic acid, and β-sitosterol showed significant promoting effects on soil microbial biomass, and they showed positive correlations with fungi and fungi/bacteria ratio. These three phenolic acids had higher contents in the poplar plantation, suggesting that poplar affo-restation had a beneficial effect on soil quality in coal-mining subsidence areas.

Analysis of phenolic compounds in different parts of pomegranate (Punica granatum) fruit by HPLC-PDA-ESI/MS and evaluation of their antioxidant activity: application to different Italian varieties.

PubMed

Russo, Marina; Fanali, Chiara; Tripodo, Giusy; Dugo, Paola; Muleo, Rosario; Dugo, Laura; De Gara, Laura; Mondello, Luigi

2018-06-01

The analysis of pomegranate phenolic compounds belonging to different classes in different fruit parts was performed by high-performance liquid chromatography coupled with photodiode array and mass spectrometry detection. Two different separation methods were optimized for the analysis of anthocyanins and hydrolyzable tannins along with phenolic acids and flavonoids. Two C 18 columns, core-shell and fully porous particle stationary phases, were used. The parameters for separation of phenolic compounds were optimized considering chromatographic resolution and analysis time. Thirty-five phenolic compounds were found, and 28 of them were tentatively identified as belonging to four different phenolic compound classes; namely, anthocyanins, phenolic acids, hydrolyzable tannins, and flavonoids. Quantitative analysis was performed with a mixture of nine phenolic compounds belonging to phenolic compound classes representative of pomegranate. The method was then fully validated in terms of retention time precision, expressed as the relative standard deviation, limit of detection, limit of quantification, and linearity range. Phenolic compounds were analyzed directly in pomegranate juice, and after solvent extraction with a mixture of water and methanol with a small percentage of acid in peel and pulp samples. The accuracy of the extraction method was also assessed, and satisfactory values were obtained. Finally, the method was used to study identified analytes in pomegranate juice, peel, and pulp of six different Italian varieties and one international variety. Differences in phenolic compound profiles among the different pomegranate parts were observed. Pomegranate peel samples showed a high concentration of phenolic compounds, ellagitannins being the most abundant ones, with respect to pulp and juice samples for each variety. With the same samples, total phenols and antioxidant activity were evaluated through colorimetric assays, and the results were correlated among them.

Inhibited phenol ionization in reverse micelles: confinement effect at the nanometer scale.

PubMed

Silva, O Fernando; Fernández, Mariana A; Silber, Juana J; de Rossi, Rita H; Correa, N Mariano

2012-01-16

We found that the absorption spectra of 2-acetylphenol (2-HAP), 4-acetylphenol (4-HAP), and p-nitrophenol (p-NPh) in water/sodium 1,4-bis(2-ethylhexyl)sulfosuccinate (AOT)/n-heptane reverse micelles (RMs) at various W(0) (W(0) = [H(2)O]/[surfactant]) values studied changed with time if (-)OH ions were present in the RM water pool. There is an evolution of ionized phenol (phenolate) bands to nonionized phenol absorption bands with time and this process is faster at low W(0) values and with phenols with higher bulk water pK(a) values. That is, in bulk water and at the hydroxide anion concentration used, only phenolate species are observed, whereas in AOT RMs at this fixed hydroxide anion concentration, ionized phenols convert into nonionized phenol species over time. Furthermore, we demonstrate that, independent of the (-)OH concentration used to prepare the AOT RMs, the nonionized phenols are the more stable species in the RM media. We explain our results by considering that strong hydrogen-bonding interactions between phenols and the AOT polar head groups result in the existence of only nonionized phenols at the AOT RM interface. The situation is quite different when the phenols are dissolved in cationic benzyl-n-hexadecyldimethylammonium chloride RMs. Therein, only phenolates species are present at the (-)OH concentrations used. The results clearly demonstrate that the classical definition of pH does not apply in a confined environment, such as in the interior of RMs and challenge the general idea that pH can be determined inside RMs. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phenolic acids in the flowers of Althaea rosea var. nigra.

PubMed

Dudek, Marlena; Matławska, Irena; Szkudlarek, Maurycy

2006-01-01

Distribution of phenolic acids in the flowers of Althaea rosea var. nigra has been studied by 2D-TLC and HPLC methods. The phenolic acids occurring in these fractions have been identified as ferulic, vanillic, syringic, p-coumaric, p-hydroxybenzoic, p-hydroxyphenylacetic and caffeic acids. By means of the HPLC methods the contents of major phenolic acids were estimated. From among the phenolic acids analyzed the syringic, p-hydroxybenzoic and p-coumaric acids are dominant. Total content of phenolic acids was determined by the Arnov's method.

The reactivity of phenolic and non-phenolic residual kraft lignin model compounds with Mn(II)-peroxidase from Lentinula edodes.

PubMed

Crestini, C; D'Annibale, A; Sermanni, G G; Saladino, R

2000-02-01

Three phenolic model compounds representing bonding patterns of residual kraft lignin were incubated with manganese peroxidase from Lentinula edodes. Extensive degradation of all the phenolic models, mainly occurring via side-chain benzylic oxidation, was observed. Among the tested model compounds the diphenylmethane alpha-5 phenolic model was found to be the most reactive, yielding several products showing oxidation and fragmentation at the bridging position. The non-phenolic 5-5' biphenyl and 5-5' diphenylmethane models were found unreactive.

Influence of different nominal molecular weight fractions of humic acids on phenol oxidation by permanganate.

PubMed

He, Di; Guan, Xiaohong; Ma, Jun; Yu, Min

2009-11-01

The effects of humic acid (HA) and its different nominal molecular weight (NMW) fractions on the phenol oxidation by permanganate were studied. Phenol oxidation by permanganate was enhanced by the presence of HA at pH 4-8, while slightly inhibited at pH 9-10. The effects of HA on phenol oxidation by permanganate were dependent on HA concentration and permanganate/phenol molar ratios. The high NMW fractions of HA enhanced phenol oxidation by permanganate at pH 7 more significantly than the low fractions of HA. The apparent second-order rate constants of phenol oxidation by permanganate in the presence of HA correlated well with their specific ultraviolet absorption (SUVA) at 254 nm and specific violet absorption (SVA) at 465 or 665 nm. High positive correlation coefficients (R(2) > 0.72) implied that pi-electrons of HA strongly influenced the reactivity of phenol towards permanganate oxidation which agreed well with the information provided by fluorescence spectroscopy. The FTIR analysis indicated that the HA fractions rich in aliphatic character, polysaccharide-like substances, and the amount of carboxylate groups had less effect on phenol oxidation by permanganate. The negative correlation between the rate constants of phenol oxidation by permanganate and O/C ratios suggested that the oxidation of phenol increased with a decrease in the content of oxygen-containing functional groups.

Phenolic content variability and its chromosome location in tritordeum

PubMed Central

Navas-Lopez, José F.; Ostos-Garrido, Francisco J.; Castillo, Almudena; Martín, Antonio; Gimenez, Maria J.; Pistón, Fernando

2014-01-01

For humans, wheat is the most important source of calories, but it is also a source of antioxidant compounds that are involved in the prevention of chronic disease. Among the antioxidant compounds, phenolic acids have great potential to improve human health. In this paper we evaluate the effect of environmental and genetic factors on the phenolics content in the grain of a collection of tritordeums with different cytoplasm and chromosome substitutions. To this purpose, tritordeum flour was used for extraction of the free, conjugates and bound phenolic compounds. These phenolic compounds were identified and quantified by RP-HPLC and the results were analyzed by univariate and multivariate methods. This is the first study that describes the composition of phenolic acids of the amphiploid tritordeum. As in wheat, the predominant phenolic compound is ferulic acid. In tritordeum there is great variability for the content of phenolic compounds and the main factor which determines its content is the genotype followed by the environment, in this case included in the year factor. Phenolic acid content is associated with the substitution of chromosome DS1D(1Hch) and DS2D(2Hch), and the translocation 1RS/1BL in tritordeum. The results show that there is high potential for further improving the quality and quantity of phenolics in tritordeum because this amphiploid shows high variability for the content of phenolic compounds. PMID:24523725

The toxicity of binary mixture of Cu (II) ion and phenols on Tetrahymena thermophila.

PubMed

Luo, Hui; Li, Xi; Fang, Tingting; Liu, Peng; Zhang, Chaocan; Xie, Hao; Sun, Enjie

2015-03-01

The toxicity of binary mixture of Cu(2+) and phenols (phenol; o-nitrophenol; m-nitrophenol; p-nitrophenol) was evaluated using Tetrahymena thermophila as the model organism, by microcalorimetry, optical density, field emission scanning electron microscope (FESEM) and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). The growth curves and metabolic properties of Tetrahymena exposed to Cu(2+) and phenols were monitored by microcalorimetry. Binary mixture toxicity changed with the concentration of Cu(2+)/phenols and the order of toxicity was Cu(2+)/phenol

Obtention and characterization of phenolic extracts from different cocoa sources.

PubMed

Ortega, Nàdia; Romero, Maria-Paz; Macià, Alba; Reguant, Jordi; Anglès, Neus; Morelló, José-Ramón; Motilva, Maria-Jose

2008-10-22

The aim of this study was to evaluate several cocoa sources to obtain a rich phenol extract for use as an ingredient in the food industry. Two types of phenolic extracts, complete and purified, from different cocoa sources (beans, nibs, liquor, and cocoa powder) were investigated. UPLC-MS/MS was used to identify and quantify the phenolic composition of the extracts, and the Folin-Ciocalteu and vanillin assays were used to determine the total phenolic and flavan-3-ol contents, respectively. The DPPH and ORAC assays were used to measure their antioxidant activity. The results of the analysis of the composition of the extracts revealed that the major fraction was procyanidins, followed by flavones and phenolic acids. From the obtained results, the nib could be considered the most interesting source for obtaining a rich phenolic cocoa extract because of its rich phenolic profile content and high antioxidant activity in comparison with the other cocoa sources.

Flammability and Photo-Stability of Selected Polymer Systems

DTIC Science & Technology

1981-06-01

modifications. The 13. following methods have been used(2 8 ) : 1. Etherification or esterification of the phenolic hydroxyl groups, 2. Complex...is initiated with a view to making modifications of the flammability behaviors of phenolic resin by using substituted phenols. Also. esterification of...n-substituted phenolic resins. Modification by esterification has also been reported by Lei(29) in the synthesis of n-chloro- phenolic fiber. The

Phenolic Composition and Evaluation of the Antimicrobial Activity of Free and Bound Phenolic Fractions from a Peruvian Purple Corn (Zea mays L.) Accession.

PubMed

Gálvez Ranilla, Lena; Christopher, Ashish; Sarkar, Dipayan; Shetty, Kalidas; Chirinos, Rosana; Campos, David

2017-12-01

Beneficial effects on overall gut health by phenolic bioactives-rich foods are potentially due to their modulation of probiotic gut bacteria and antimicrobial activity against pathogenic bacteria. Based on this rationale, the effect of the free and bound phenolic fractions from a Peruvian purple corn accession AREQ-084 on probiotic lactic acid bacteria such as Lactobacillus helveticus and Bifidobacterium longum and the gastric cancer-related pathogen Helicobacter pylori was evaluated. The free and bound phenolic composition was also determined by ultra-performance liquid chromatography. Anthocyanins were the major phenolic compounds (310.04 mg cyanidin-3-glucoside equivalents/100 g dry weight, DW) in the free phenolic fraction along with hydroxycinnamic acids such as p-coumaric acid derivatives, followed by caffeic and ferulic acid derivatives. The bound phenolic form had only hydroxycinnamic acids such as ferulic acid, p-coumaric acid, and a ferulic acid derivative with ferulic acid being the major phenolic compound (156.30 mg/100 g DW). These phenolic compounds were compatible with beneficial probiotic lactic acid bacteria such as L. helveticus and B. longum as these bacteria were not inhibited by the free and bound phenolic fractions at 10 to 50 mg/mL and 10 mg/mL of sample doses, respectively. However, the pathogenic H. pylori was also not inhibited by both purple corn phenolic forms at same above sample doses. This study provides the preliminary base for the characterization of phenolic compounds of Peruvian purple corn biodiversity and its potential health benefits relevant to improving human gut health. This study provides insights that Peruvian purple corn accession AREQ-084 can be targeted as a potential source of health-relevant phenolic compounds such as anthocyanins along with hydroxycinnamic acids linked to its dietary fiber fraction. Additionally, these phenolic fractions did not affect the gut health associated beneficial bacteria nor the pathogenic H. pylori. Purple corn can be targeted for design of probiotic functional foods integrated with their anthocyanin linked-coloring properties. © 2017 Institute of Food Technologists®.

Treatment of wastewater containing phenol using a tubular ceramic membrane bioreactor.

PubMed

Ersu, C B; Ong, S K

2008-02-01

The performance of a membrane bioreactor (MBR) with a tubular ceramic membrane for phenol removal was evaluated under varying hydraulic retention times (HRT) and a fixed sludge residence time (SRT) of 30 days. The tubular ceramic membrane was operated with a mode of 15 minutes of filtration followed by 15 seconds of permeate backwashing at a flux of 250 l m(-2)hr(-1) along with an extended backwashing of 30 seconds every 3 hours of operation, which maintained the transmembrane pressure (TMP) below 100 kPa. Using a simulated municipal wastewater with varying phenol concentrations, the chemical oxygen demand (COD) and phenol removals observed were greater than 88% with excellent suspended solids (SS) removal of 100% at low phenol concentrations (approx. 100 mg l(-1) of phenol). Step increases in phenol concentration showed that inhibition was observed between 600 to 800 mg l(-1) of phenol with decreased sludge production rate, mixed liquor suspended solids (MLSS) concentration, and removal performance. The sludge volume index (SVI) of the biomass increased to about 450 ml g(-1) for a phenol input concentration of 800 mg l(-1). When the phenol concentration was decreased to 100 mg l(-1), the ceramic tubular MBR was found to recover rapidly indicating that the MBR is a robust system retaining most of the biomass. Experimental runs using wastewater containing phenol indicated that the MBR can be operated safely without upsets for concentrations up to 600 mg l(-1) of phenol at 2-4 hours HRT and 30 days SRT.

Breads enriched with guava flour as a tool for studying the incorporation of phenolic compounds in bread melanoidins.

PubMed

Alves, Genilton; Perrone, Daniel

2015-10-15

In the present study we aimed at studying, for the first time, the incorporation of phenolic compounds into bread melanoidins. Fermentation significantly affected the phenolics profile of bread doughs. Melanoidins contents continuously increased from 24.1 mg/g to 71.9 mg/g during baking, but their molecular weight decreased at the beginning of the process and increased thereafter. Enrichment of white wheat bread with guava flour increased the incorporation of phenolic compounds up to 2.4-fold. Most phenolic compounds showed higher incorporation than release rates during baking, leading to increases from 3.3- to 13.3-fold in total melanoidin-bound phenolics. Incorporation patterns suggested that phenolic hydroxyls, but not glycosidic bonds of melanoidin-bound phenolics are cleaved during thermal processing. Antioxidant capacity of bread melanoidins increased due to enrichment with guava flour and increasing baking periods and was partially attributed to bound phenolics. Moreover, FRAP assay was more sensitive to measure this parameter than TEAC assay. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fermentation and complex enzyme hydrolysis for improving the total soluble phenolic contents, flavonoid aglycones contents and bio-activities of guava leaves tea.

PubMed

Wang, Lu; Luo, You; Wu, Yanan; Liu, Yan; Wu, Zhenqiang

2018-10-30

There are both soluble and insoluble-bound forms of phenolics in tea-leaf products. In order to increase total soluble phenolics contents, guava leaves tea (GLT) was first fermented with Monascus anka and Saccharomyces cerevisiae, and then hydrolyzed with complex enzymes. The changes in phenolics profiles, antioxidant activities and inhibitory effect on α-glucosidase in processed GLT were investigated. Compared with the un-fermented GLT, fermentation and complex enzymatic processing (FE) significantly increased the total phenolics, total flavonoids, quercetin and kaempferol contents by 2.1, 2.0, 13.0 and 6.8 times, respectively. After the FE, a major proportion of phenolics existed in the soluble form. Quercetin was released in the highest amount among different phenolics. In addition, soluble phenolic extracts from GLT following FE exhibited a highest antioxidant activity and inhibitory effect on α-glucosidase. The paper suggested an improved method for processing GLT into high-value products rich in phenolics and flavonoids aglycones with enhanced health benefits. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dynamic Changes in Phenolics and Antioxidant Capacity during Pecan (Carya illinoinensis) Kernel Ripening and Its Phenolics Profiles.

PubMed

Jia, Xiaodong; Luo, Huiting; Xu, Mengyang; Zhai, Min; Guo, Zhongren; Qiao, Yushan; Wang, Liangju

2018-02-16

Pecan ( Carya illinoinensis ) kernels have a high phenolics content and a high antioxidant capacity compared to other nuts-traits that have attracted great interest of late. Changes in the total phenolic content (TPC), condensed tannins (CT), total flavonoid content (TFC), five individual phenolics, and antioxidant capacity of five pecan cultivars were investigated during the process of kernel ripening. Ultra-performance liquid chromatography coupled with quadruple time-of-flight mass (UPLC-Q/TOF-MS) was also used to analyze the phenolics profiles in mixed pecan kernels. TPC, CT, TFC, individual phenolics, and antioxidant capacity were changed in similar patterns, with values highest at the water or milk stages, lowest at milk or dough stages, and slightly varied at kernel stages. Forty phenolics were tentatively identified in pecan kernels, of which two were first reported in the genus Carya , six were first reported in Carya illinoinensis , and one was first reported in its kernel. The findings on these new phenolic compounds provide proof of the high antioxidant capacity of pecan kernels.

Determination of free, esterified, glycosylated and insoluble-bound phenolics composition in the edible part of araticum fruit (Annona crassiflora Mart.) and its by-products by HPLC-ESI-MS/MS.

PubMed

Arruda, Henrique Silvano; Pereira, Gustavo Araujo; de Morais, Damila Rodrigues; Eberlin, Marcos Nogueira; Pastore, Glaucia Maria

2018-04-15

Phenolics present in the free, esterified, glycosylated and insoluble-bound forms of araticum pulp, peel and seed were for the first time characterized and quantified using HPLC-ESI-MS/MS. Levels of total phenolics, flavonoids, condensed tannins and antioxidant activities from araticum fruit followed the order peel > pulp > seed. Overall, insoluble-bound and esterified phenolics were the dominant forms of phenolics from araticum fruit parts and the highest contributors to their antioxidant activities. Extracts were found to contain contrasting levels of phenolics that were specific to each fruit part. From 10 phenolics quantified in araticum fruit, catechin and epicatechin were the major ones from pulp and peel, whereas seed displayed caffeic acid, catechin and epicatechin as its main phenolics. Araticum fruit was found to provide a good source of phenolics, and the full exploitation of this fruit may find applications in the food, cosmetic and pharmaceutical industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

In-Depth Two-Year Study of Phenolic Profile Variability among Olive Oils from Autochthonous and Mediterranean Varieties in Morocco, as Revealed by a LC-MS Chemometric Profiling Approach.

PubMed

Bajoub, Aadil; Medina-Rodríguez, Santiago; Olmo-García, Lucía; Ajal, El Amine; Monasterio, Romina P; Hanine, Hafida; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría

2016-12-28

Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars ("Picholine Marocaine", "Dahbia", "Haouzia" and "Menara"), and nine Mediterranean varieties recently introduced in Morocco ("Arbequina", "Arbosana", "Cornicabra", "Frantoio", "Hojiblanca", "Koroneiki", "Manzanilla", "Picholine de Languedoc" and "Picual"), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils.

Effects of Vinification Techniques Combined with UV-C Irradiation on Phenolic Contents of Red Wines.

PubMed

Tahmaz, Hande; Söylemezoğlu, Gökhan

2017-06-01

Red wines are typically high in phenolic and antioxidant capacity and both of which can be increased by vinification techniques. This study employed 3 vinification techniques to assess the increase in phenolic compounds and antioxidant capacity. Wines were obtained from Boğazkere grape cultivar by techniques of classical maceration, cold maceration combined with ultraviolet light (UV) irradiation, and thermovinification combined with UV irradiation and changes in phenolic contents were examined. Total phenolic and anthocyanin contents and trolox equivalent antioxidant capacity of wines were measured spectrophotometrically and phenolic contents (+)-catechin, (-)-epicatechin, rutin, quercetin, trans-resveratrol, and cis-resveratrol were measured by High Pressure Liquid Chromatography with Diode Array Detection (HPLC-DAD). As a result of the study, the highest phenolic content except for quercetin was measured in the wines obtained by thermovinification combined with UV irradiation. We demonstrated that the highest phenolic compounds with health effect, total phenolic compounds, total anthocyanin, and antioxidant activity were obtained from thermovinification with UV-C treatment than classical wine making. © 2017 Institute of Food Technologists®.

The impact of drying techniques on phenolic compound, total phenolic content and antioxidant capacity of oat flour tarhana.

PubMed

Değirmencioğlu, Nurcan; Gürbüz, Ozan; Herken, Emine Nur; Yıldız, Aysun Yurdunuseven

2016-03-01

In this study, the changes in phenolic composition, total phenolic content, and antioxidant capacity of tarhanas supplemented with oat flour (OF) at the levels of 20-100% (w/w) after three drying treatments (sun-, oven-, and microwave drying) were investigated. A total of seventeen phenolic standards have been screened in tarhanas, and the most abundant flavonol and phenolic acid compounds were kaempferol (23.62mg/g) and 3-hydroxy-4-metoxy cinnamic acid (9.60mg/g). The total phenolic content amount gradually increased with the addition of OF to tarhana, but decidedly higher total phenolic content was found in samples oven dried at 55°C as compared with other methods. The microwave- and oven dried tarhana samples showed higher TEACDPPH and TEACABTS values than those dried with the other methods, respectively, in higher OF amounts. Consequently, oven- and microwave-drying can be recommended to retain the highest for phenolic compounds as well as maximal antioxidant capacity in OF supplemented tarhana samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comprehensive Characterization of Extractable and Nonextractable Phenolic Compounds by High-Performance Liquid Chromatography-Electrospray Ionization-Quadrupole Time-of-Flight of a Grape/Pomegranate Pomace Dietary Supplement.

PubMed

Pérez-Ramírez, Iza F; Reynoso-Camacho, Rosalía; Saura-Calixto, Fulgencio; Pérez-Jiménez, Jara

2018-01-24

Grape and pomegranate are rich sources of phenolic compounds, and their derived products could be used as ingredients for the development of functional foods and dietary supplements. However, the profile of nonextractable or macromolecular phenolic compounds in these samples has not been evaluated. Here, we show a comprehensive characterization of extractable and nonextractable phenolic compounds of a grape/pomegranate pomace dietary supplement using high-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight (HPLC-ESI-QTOF) and matrix-assisted laser desorption/ionization (MALDI)-TOF techniques. The main extractable phenolic compounds were several anthocyanins (principally malvidin 3-O-glucoside) as well as gallotannins and gallagyl derivatives; some phenolic compounds were reported in grape or pomegranate for the first time. Additionally, there was a high proportion of nonextractable phenolic compounds, including vanillic acid, and dihydroxybenzoic acid. Unidentified polymeric structures were detected by MALDI-TOF MS analysis. This study shows that mixed grape and pomegranate pomaces are a source of different classes of phenolic compounds including a high proportion of nonextractable phenolic compounds.

Biodegradation of Phenolic Contaminants: Current Status and Perspectives

NASA Astrophysics Data System (ADS)

Zhao, Lin; Wu, Qi; Ma, Aijin

2018-01-01

Phenolic compounds, a class of toxic pollutants in water, come mainly from a variety of industrial processes. The industrial application for biodegradation has become an important topic in recent years. In this review, we discuss the present situation, properties, and pollution characteristics of phenolic contaminants, factors affecting the degradation of phenols, microbial species and biodegradation methods. The challenges and opportunities in developing biodegradation processes of phenolic contaminants are also discussed.

U-Shape Suppressive Effect of Phenol Red on the Epileptiform Burst Activity via Activation of Estrogen Receptors in Primary Hippocampal Culture

PubMed Central

Liu, Xu; Chen, Ben; Chen, Lulan; Ren, Wan-Ting; Liu, Juan; Wang, Guoxiang; Fan, Wei; Wang, Xin; Wang, Yun

2013-01-01

Phenol red is widely used in cell culture as a pH indicator. Recently, it also has been reported to have estrogen-like bioactivity and be capable of promoting cell proliferation in different cell lines. However, the effect of phenol red on primary neuronal culture has never been investigated. By using patch clamp technique, we demonstrated that hippocampal pyramidal neurons cultured in neurobasal medium containing no phenol red had large depolarization-associated epileptiform bursting activities, which were rarely seen in neurons cultured in phenol red-containing medium. Further experiment data indicate that the suppressive effect of the phenol red on the abnormal epileptiform burst neuronal activities was U-shape dose related, with the most effective concentration at 28 µM. In addition, this concentration related inhibitory effect of phenol red on the epileptiform neuronal discharges was mimicked by 17-β-estradiol, an estrogen receptor agonist, and inhibited by ICI-182,780, an estrogen receptor antagonist. Our results suggest that estrogen receptor activation by phenol red in the culture medium prevents formation of abnormal, epileptiform burst activity. These studies highlight the importance of phenol red as estrogen receptor stimulator and cautions of careful use of phenol red in cell culture media. PMID:23560076

Breeding Vegetables with Increased Content in Bioactive Phenolic Acids.

PubMed

Kaushik, Prashant; Andújar, Isabel; Vilanova, Santiago; Plazas, Mariola; Gramazio, Pietro; Herraiz, Francisco Javier; Brar, Navjot Singh; Prohens, Jaime

2015-10-09

Vegetables represent a major source of phenolic acids, powerful antioxidants characterized by an organic carboxylic acid function and which present multiple properties beneficial for human health. In consequence, developing new varieties with enhanced content in phenolic acids is an increasingly important breeding objective. Major phenolic acids present in vegetables are derivatives of cinnamic acid and to a lesser extent of benzoic acid. A large diversity in phenolic acids content has been found among cultivars and wild relatives of many vegetable crops. Identification of sources of variation for phenolic acids content can be accomplished by screening germplasm collections, but also through morphological characteristics and origin, as well as by evaluating mutations in key genes. Gene action estimates together with relatively high values for heritability indicate that selection for enhanced phenolic acids content will be efficient. Modern genomics and biotechnological strategies, such as QTL detection, candidate genes approaches and genetic transformation, are powerful tools for identification of genomic regions and genes with a key role in accumulation of phenolic acids in vegetables. However, genetically increasing the content in phenolic acids may also affect other traits important for the success of a variety. We anticipate that the combination of conventional and modern strategies will facilitate the development of a new generation of vegetable varieties with enhanced content in phenolic acids.

[Role of NO signal in ABA-induced phenolic acids accumulation in Salvia miltiorrhiza hairy roots].

PubMed

Shen, Lihong; Ren, Jiahui; Jin, Wenfang; Wang, Ruijie; Ni, Chunhong; Tong, Mengjiao; Liang, Zongsuo; Yang, Dongfeng

2016-02-01

To investigate roles of nitric oxide (NO) signal in accumulations of phenolic acids in abscisic.acid (ABA)-induced Salvia miltiorrhiza hairy roots, S. miltiorrhiza hairy roots were treated with different concentrations of sodium nitroprusside (SNP)-an exogenous NO donor, for 6 days, and contents of phenolic acids in the hairy roots are determined. Then with treatment of ABA and NO scavenger (2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylimidazoline-1- oxyl-3-oxide, c-PTIO) or NO synthase inhibitor (NG-nitro-L-arginine methyl ester, L-NAME), contents of phenolic acids and expression levels of three key genes involved in phenolic acids biosynthesis were detected. Phenolic acids production in S. miltiorrhiza hairy roots was most significantly improved by 100 µmoL/L SNP. Contents of RA and salvianolic acid B increased by 3 and 4 folds. ABA significantly improved transcript levels of PAL (phenylalanine ammonia lyase), TAT (tyrosine aminotransferase) and RAS (rosmarinic acid synthase), and increased phenolic acids accumulations. However, with treatments of ABA+c-PTIO or ABA+L-NAME, accumulations of phenolic acids and expression levels of the three key genes were significantly inhibited. Both NO and ABA can increase accumulations of phenolic acids in S. miltiorrhiza hairy roots. NO signal probably mediates the ABA-induced phenolic acids production.

Changes of the phenolic compounds and antioxidant activities in germinated adlay seeds.

PubMed

Xu, Lei; Wang, Pei; Ali, Barkat; Yang, Na; Chen, Yisheng; Wu, Fengfeng; Xu, Xueming

2017-09-01

Over the years, germinated adlay products have been used as both food source and folk medicine. This study investigated the changes of total phenolic content (TPC), total flavonoid content (TFC), antioxidant activities, and phenolic acid profiles of adlay seed during germination. Results revealed that phenolic compounds and antioxidant activities varied with the germination stages. Germination significantly increased the free form phenolic and flavonoid contents by 112.5% and 168.3%, respectively. However, both of the bound form phenolic and flavonoid contents significantly decreased after germination. Phenolic acid compositions were quantified via HPLC analysis, and the levels of vanillic, p-coumaric, caffeic, hydroxybenzoic and protocatechuic acids in the free phenolic extracts were found to be significantly increased. The improvement of the free and total phenolic and flavonoid contents by the germination process led to a significant enhancement of the antioxidant activities (evaluated by the ABTS, FRAP and ORAC assays). The TPC showed the highest correlation with ORAC values (r = 0.9979). Germinated adlay had higher free and total phenolic and flavonoid contents, and antioxidant activities than ungerminated adlay. This study indicates that germinated adlay could be a promising functional food, more suitable for human consumption. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Peroxidase extraction from jicama skin peels for phenol removal

NASA Astrophysics Data System (ADS)

Chiong, T.; Lau, S. Y.; Khor, E. H.; Danquah, M. K.

2016-06-01

Phenol and its derivatives exist in various types of industrial effluents, and are known to be harmful to aquatic lives even at low concentrations. Conventional treatment technologies for phenol removal are challenged with long retention time, high energy consumption and process cost. Enzymatic treatment has emerged as an alternative technology for phenol removal from wastewater. These enzymes interact with aromatic compounds including phenols in the presence of hydrogen peroxide, forming free radicals which polymerize spontaneously to produce insoluble phenolic polymers. This work aims to extract peroxidase from agricultural wastes materials and establish its application for phenol removal. Peroxidase was extracted from jicama skin peels under varying extraction conditions of pH, sample-to-buffer ratio (w/v %) and temperature. Experimental results showed that extraction process conducted at pH 10, 40% w/v and 25oC demonstrated a peroxidase activity of 0.79 U/mL. Elevated temperatures slightly enhanced the peroxidase activities. Jicama peroxidase extracted at optimum extraction conditions demonstrated a phenol removal efficiency of 87.5% at pH 7. Phenol removal efficiency was ∼ 97% in the range of 30 - 40oC, and H2O2 dosage has to be kept below 100 mM for maximum removal under phenol concentration tested.

Phenol oxidation by a sequential CWPO-CWAO treatment with a Fe/AC catalyst.

PubMed

Quintanilla, A; Fraile, A F; Casas, J A; Rodríguez, J J

2007-07-31

Catalytic wet peroxide oxidation (CWPO) of phenol with a homemade Fe/activated carbon (Fe/AC) catalyst has been studied in a stainless steel fixed-bed reactor at different operating conditions (T=23-100 degrees C, P(T)=1-8atm, W=0-2.5g, and tau=20-320g(CAT)h/g(Phenol)). The results show that, thanks to the incorporation of Fe on the activated carbon, phenol conversion improved dramatically, reaching a 90% at 65 degrees C, 2atm, and 40g(CAT)h/g(Phenol). However, TOC conversion values remain fairly low, (around 5% at 40g(CAT)h/g(Phenol)), and no improvement was obtained with the inclusion of Fe. The presence of Fe seems to promote the nondesirable coupling reactions that take place in CWPO of phenol due to the condensation of the ring intermediates (the primary phenol oxidation products). These condensation products are quite refractory to CWPO at the conditions employed. Taking advantage of the high phenol conversions in CWPO and the high phenol mineralization in CWAO, along with the good stability of the Fe/AC catalyst, a CWPO-CWAO sequential treatment has been successfully performed by using a fixed-bed and trickle-bed reactor in series. A CWPO treatment at ambient conditions followed by a CWAO treatment at mild conditions (100 degrees C and 8atm) is presented as high efficiency process for the decontamination of phenolic wastewaters.

Biofilm coupled with UV irradiation for phenol degradation and change of its community structure.

PubMed

Xia, Siqing; Yan, Ning; Zhu, Jun; Zhang, Yongming

2011-06-01

The extensive use of phenol compounds and the inability to remove these compounds during wastewater treatment have resulted in the widespread occurrence of phenols in the natural environment. Phenols have been linked to serious risks to human and environmental health. Hence, the need to develop technologies that can effectively remove phenols from wastewater and source waters is a pressing challenge. In this study, light ceramic particles were immersed in activated sludge acclimated to degrade phenol, and microorganisms were allowed to attach to the particles surface to form biofilm. Then the ceramic particles with biofilm were moved into the photolytic circulating-bed biofilm reactor made of quartz glass, which was used for the degradation of phenol by three protocols: photolysis with UV light alone (P), biodegradation alone (B), and the two mechanisms operating simultaneously (photobiodegradation, P&B). The experimental results indicated that phenol removal rate was quickest by B experiment. However, P&B experiment gave more complete mineralization of phenol than that by other protocols. During P&B experiment, the microorganisms grown on porous ceramic carrier still kept the bioactivity degrading phenol, even under UV light irradiation. However, the dominant members of the bacterial community changed dramatically after the intimately coupled photobiodegradation, according to molecular biological analysis to the biofilm. Whereas Beijerinckia sp. was the dominant strain in the inoculum, it was replaced by Thauera sp. MZ1T that played a main role on degrading phenol during P&B experiment.

Phenolics content and antioxidant activity of tartary buckwheat from different locations.

PubMed

Guo, Xu-Dan; Ma, Yu-Jie; Parry, John; Gao, Jin-Ming; Yu, Liang-Li; Wang, Min

2011-11-25

Two tartary buckwheat samples (Xingku No.2 and Diqing) grown at three locations were analyzed for free and bound phenolic content and antioxidant properties. Moreover, the relative contributions of variety and growing environment to phenolic content and antioxidant properties were determined, as well as correlations of these properties to growing conditions. The total phenolic contents varied from 5,150 to 9,660 μmol of gallic acid equivalents per 100 gram of dry weight (DW) of tartary buckwheat and the free phenolics accounted for 94% to 99%. Rutin content was in the range from 518.54 to 1,447.87 mg per 100 gram of DW of tartary buckwheat. p-Hydroxybenzoic, ferulic and protocatechuic acids were the prominent phenolic acids and other phenolics, including p-coumaric, gallic, caffeic, vanillic and syringic acids were also detected. Tartary buckwheat exhibited higher DPPH· and ABTS·+ scavenging activities and was more effective at preventing the bleaching of β-carotene in comparison with reference antioxidant and plant phenolics constituents. Additionally, growing conditions and the interaction between variety and environment may have more contribution than variety to individual phenolics and antioxidant properties of tartary buckwheat. Environmental parameters such as higher altitudes may also have an increasing effect on rutin and phenolic acids. This study suggests that tartary buckwheat has potential health benefits because of its high phenolic content and antioxidant properties. These components could also be enhanced by optimizing the growing conditions of a selected variety.

Influence of rye flour enzymatic biotransformation on the antioxidant capacity and transepithelial transport of phenolic acids.

PubMed

de Lima, Fabíola Aliaga; Martins, Isabela Mateus; Faria, Ana; Calhau, Conceição; Azevedo, Joana; Fernandes, Iva; Mateus, Nuno; Macedo, Gabriela Alves

2018-03-01

Phenolic acids have been reported to play a role on the antioxidant activity and other important biological activities. However, as most polyphenolics in food products are either bound to cellular matrices or present as free polymeric forms, the way they are absorbed has not been totally clear until now. Hydrolytic enzymes may act to increase functionalities in polyphenolic-rich foods, enhancing the bioaccessibility of phenolic compounds and minerals from whole grains. The aim of this study was to evaluate the action of tannin acyl hydrolase (tannase) on the total phenols, phenolic acid profile, antioxidant capacity and in vitro bioaccessibility of phenolic acids found in whole rye flour (RF). Besides increasing total phenols and the antioxidant capacity, tannase treatment increased the amounts of ferulic, sinapic and vanillic acids identified in RF, evidencing a new type of feruloyl esterase catalytic action of tannase. Vanillic and sinapic acids in tannase-treated whole rye flour (RFT) were higher than RF after in vitro gastrointestinal digestion, and higher amounts of transported vanillic acid through the Caco-2 monolayer were detected in RFT. However, the bioaccessibility and the transport efficiency of RF phenolic acids were higher than RFT. Underutilized crops like rye and rye-derived products may be an important source of phenolic acids. The tannase biotransformation, even influencing the total phenolics and antioxidant capacity of RF, did not increase the bioaccessibility of phenolic acids under the experimental conditions of this study.

Impact of boiling on free and bound phenolic profile and antioxidant activity of commercial gluten-free pasta.

PubMed

Rocchetti, Gabriele; Lucini, Luigi; Chiodelli, Giulia; Giuberti, Gianluca; Montesano, Domenico; Masoero, Francesco; Trevisan, Marco

2017-10-01

Cooking by boiling dry pasta could have varying degrees of influence on nutritional and functional components. In the present study, its effect on total phenolic content and antioxidant capacity, as well as on the comprehensive profile of free and bound phenolics, was investigated in six commercial gluten-free (GF) pasta products. Overall, the heat treatment caused a significant reduction (P<0.01) of the total phenolic content as well as FRAP reducing power and ORAC radical scavenging, with significant differences among the pasta samples considered. The highest values were recorded in free phenolic fraction remaining in black rice (41mggallic acid equivalents100g -1 and 25mmolTrolox Equivalents100g -1 ) and quinoa (24mggallic acid equivalents100g -1 and 14mmolTrolox Equivalents100g -1 ) cooked GF pasta. Significant correlations (P<0.01) could be found between total phenolics and both the antioxidant capacity assays performed. UHPLC-ESI/QTOF-MS mass profiling allowed confirming the spectrophotometric results, while identifying the amount of free and bound fractions. Among phenolic classes, lignans exhibited the highest decrease during the cooking process, followed by stilbenes and flavonoids. However, phenolic acids and other phenolics showed the highest stability. Furthermore, cooking by boiling strongly lowered the bound-to-free ratio of phenolic compounds, by an averaged factor ranging from 14-folds for flavonoids to 5-folds for other classes of phenolics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Process for preparing phenolic formaldehyde resole resin products derived from fractionated fast-pyrolysis oils

DOEpatents

Chum, Helena L.; Kreibich, Roland E.

1992-01-01

A process for preparing phenol-formaldehyde resole resins and adhesive compositions in which portions of the phenol normally contained in said resins are replaced by a phenol/neutral fractions extract obtained from fractionating fast-pyrolysis oils.

Enhancing charge storage of conjugated polymer electrodes with phenolic acids

NASA Astrophysics Data System (ADS)

Wagner, Michal; Rębiś, Tomasz; Inganäs, Olle

2016-01-01

We here present studies of electrochemical doping of poly(1-aminoanthraquinone) (PAAQ) films with three structurally different phenolic acids. The examined phenolic acids (sinapic, ferulic and syringic acid) were selected due to their resemblance to redox active groups, which can be found in lignin. The outstanding electrochemical stability of PAAQ films synthesized for this work enabled extensive cycling of phenolic acid-doped PAAQ films. Potentiodynamic and charge-discharge studies revealed that phenolic acid-doped PAAQ films exhibited enhanced capacitance in comparison to undoped PAAQ films, together with appearance of redox activity characteristics specific for each dopant. Electrochemical kinetic studies performed on microelectrodes affirmed the fast electron transfer for hydroquinone-to-quinone reactions with these phenolic compounds. These results imply the potential application of phenolic acids in cheap and degradable energy storage devices.

Efficacy of topical phenol decontamination strategies on severity of acute phenol chemical burns and dermal absorption: in vitro and in vivo studies in pig skin.

PubMed

Monteiro-Riviere, N A; Inman, A O; Jackson, H; Dunn, B; Dimond, S

2001-05-01

Pure phenol is colorless and used in the manufacture of phenolic resins, plastics, explosives, fertilizers, paints, rubber, textiles, adhesives, pharmaceuticals, paper, soap, and wood preservatives. The purpose of this study was to compare the efficacy of several phenol decontamination strategies following dermal exposure using the pig as a model for human exposure, and then assess the effect of the two best treatments on phenol absorption in the isolated perfused porcine skin flap (IPPSF). Six anesthetized Yorkshire pigs were exposed to 89% aqueous phenol for 1 min using Hilltop chambers (10 skin sites/pig; 400 microl/site). Exposure to phenol was followed by one of 10 different decontamination procedures: 1-, 5-, 15-, and 30-min water wash; Ivory soap solution; polyethylene glycol (PEG 400); PEG 400/industrial methylated spirits (IMS); PEG 400/ethanol (EtOH); polyvinyl pyrrolidone (PVP)/70% isopropanol (IPA); and 70% IPA. For each of the last five strategies, 1-min treatment washes were repeatedly alternated with 1-min water washes for a total of 15 min. Evaluation was based on scoring of erythema, edema, and histological parameters such as intracellular and intercellular epidermal edema, papillary dermal edema, perivascular infiltrates, pyknotic stratum basale cells, and epidermal-dermal separation. It was concluded that PEG 400 and 70% IPA were superior to the other treatments investigated and equally efficacious in the reduction of phenol-induced skin damage. In addition, phenol absorption was assessed utilizing the two most effective in vivo treatments in the IPPSF. The assessment of percutaneous absorption of phenol found the PEG 400, 70% IPA, and 15-min water treatments significantly (P < 0.05) reduced phenol absorption relative to no treatment.

Comparison of antioxidant activity, anthocyanins, carotenoids, and phenolics of three native fresh and sun-dried date (Phoenix dactylifera L.) varieties grown in Oman.

PubMed

Al-Farsi, Mohamed; Alasalvar, Cesarettin; Morris, Anne; Baron, Mark; Shahidi, Fereidoon

2005-09-21

Fresh and sun-dried dates of three native varieties from Oman, namely, Fard, Khasab, and Khalas, were examined for their antioxidant activity and total contents of anthocyanins, carotenoids, and phenolics, as well as free and bound phenolic acids. All results are expressed as mean value +/- standard deviation (n = 3) on a fresh weight basis. Fresh date varieties were found to be a good source of antioxidants (11687-20604 micromol of Trolox equiv/g), total contents of anthocyanins (0.24-1.52 mg of cyanidin 3-glucoside equiv/100 g), carotenoids (1.31-3.03 mg/100 g), phenolics (134-280 mg of ferulic acid equiv/100 g), free phenolic acids (2.61-12.27 mg/100 g), and bound phenolic acids (6.84-30.25 mg/100 g). A significant (p < 0.05) amount of antioxidants and carotenoids was lost after sun-drying of dates, whereas the total content of phenolics and free and bound phenolic acids increased significantly (p < 0.05). Anthocyanins were detected only in fresh dates. Date varieties had different levels and patterns of phenolic acids. Four free phenolic acids (protocatechuic acid, vanillic acid, syringic acid, and ferulic acid) and nine bound phenolic acids (gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, and o-coumaric acid) were tentatively identified. Of the date varieties studied, Khalas, which is considered to be premium quality, had higher antioxidant activity, total carotenoids, and bound phenolic acids than other varieties. These results suggest that all date varieties serve as a good source of natural antioxidants and could potentially be considered as a functional food or functional food ingredient, although some of their antioxidant constituents are lost during sun-drying.

From Olive Fruits to Olive Oil: Phenolic Compound Transfer in Six Different Olive Cultivars Grown under the Same Agronomical Conditions.

PubMed

Talhaoui, Nassima; Gómez-Caravaca, Ana María; León, Lorenzo; De la Rosa, Raúl; Fernández-Gutiérrez, Alberto; Segura-Carretero, Antonio

2016-03-04

Phenolic compounds are responsible of the nutritional and sensory quality of extra-virgin olive oil (EVOO). The composition of phenolic compounds in EVOO is related to the initial content of phenolic compounds in the olive-fruit tissues and the activity of enzymes acting on these compounds during the industrial process to produce the oil. In this work, the phenolic composition was studied in six major cultivars grown in the same orchard under the same agronomical and environmental conditions in an effort to test the effects of cultivars on phenolic composition in fruits and oils as well as on transfer between matrices. The phenolic fractions were identified and quantified using high-performance liquid chromatography-diode array detector-time-of-flight-mass spectrometry. A total of 33 phenolic compounds were determined in the fruit samples and a total of 20 compounds in their corresponding oils. Qualitative and quantitative differences in phenolic composition were found among cultivars in both matrices, as well as regarding the transfer rate of phenolic compounds from fruits to oil. The results also varied according to the different phenolic groups evaluated, with secoiridoids registering the highest transfer rates from fruits to oils. Moreover, wide-ranging differences have been noticed between cultivars for the transfer rates of secoiridoids (4.36%-65.63% of total transfer rate) and for flavonoids (0.18%-0.67% of total transfer rate). 'Picual' was the cultivar that transferred secoiridoids to oil at the highest rate, whereas 'Changlot Real' was the cultivar that transferred flavonoids at the highest rates instead. Principal-component analysis confirmed a strong genetic effect on the basis of the phenolic profile both in the olive fruits and in the oils.

Changes in Phenolic Acid Content in Maize during Food Product Processing.

PubMed

Butts-Wilmsmeyer, Carrie J; Mumm, Rita H; Rausch, Kent D; Kandhola, Gurshagan; Yana, Nicole A; Happ, Mary M; Ostezan, Alexandra; Wasmund, Matthew; Bohn, Martin O

2018-04-04

The notion that many nutrients and beneficial phytochemicals in maize are lost due to food product processing is common, but this has not been studied in detail for the phenolic acids. Information regarding changes in phenolic acid content throughout processing is highly valuable because some phenolic acids are chemopreventive agents of aging-related diseases. It is unknown when and why these changes in phenolic acid content might occur during processing, whether some maize genotypes might be more resistant to processing induced changes in phenolic acid content than other genotypes, or if processing affects the bioavailability of phenolic acids in maize-based food products. For this study, a laboratory-scale processing protocol was developed and used to process whole maize kernels into toasted cornflakes. High-throughput microscale wet-lab analyses were applied to determine the concentrations of soluble and insoluble-bound phenolic acids in samples of grain, three intermediate processing stages, and toasted cornflakes obtained from 12 ex-PVP maize inbreds and seven hybrids. In the grain, insoluble-bound ferulic acid was the most common phenolic acid, followed by insoluble-bound p-coumaric acid and soluble cinnamic acid, a precursor to the phenolic acids. Notably, the ferulic acid content was approximately 1950 μg/g, more than ten-times the concentration of many fruits and vegetables. Processing reduced the content of the phenolic acids regardless of the genotype. Most changes occurred during dry milling due to the removal of the bran. The concentration of bioavailable soluble ferulic and p-coumaric acid increased negligibly due to thermal stresses. Therefore, the current dry milling based processing techniques used to manufacture many maize-based foods, including breakfast cereals, are not conducive for increasing the content of bioavailable phenolics in processed maize food products. This suggests that while maize is an excellent source of phenolics, alternative or complementary processing methods must be developed before this nutritional resource can be utilized.

Fruit Phenolic Profiling: A New Selection Criterion in Olive Breeding Programs

PubMed Central

Pérez, Ana G.; León, Lorenzo; Sanz, Carlos; de la Rosa, Raúl

2018-01-01

Olive growing is mainly based on traditional varieties selected by the growers across the centuries. The few attempts so far reported to obtain new varieties by systematic breeding have been mainly focused on improving the olive adaptation to different growing systems, the productivity and the oil content. However, the improvement of oil quality has rarely been considered as selection criterion and only in the latter stages of the breeding programs. Due to their health promoting and organoleptic properties, phenolic compounds are one of the most important quality markers for Virgin olive oil (VOO) although they are not commonly used as quality traits in olive breeding programs. This is mainly due to the difficulties for evaluating oil phenolic composition in large number of samples and the limited knowledge on the genetic and environmental factors that may influence phenolic composition. In the present work, we propose a high throughput methodology to include the phenolic composition as a selection criterion in olive breeding programs. For that purpose, the phenolic profile has been determined in fruits and oils of several breeding selections and two varieties (“Picual” and “Arbequina”) used as control. The effect of three different environments, typical for olive growing in Andalusia, Southern Spain, was also evaluated. A high genetic effect was observed on both fruit and oil phenolic profile. In particular, the breeding selection UCI2-68 showed an optimum phenolic profile, which sums up to a good agronomic performance previously reported. A high correlation was found between fruit and oil total phenolic content as well as some individual phenols from the two different matrices. The environmental effect on phenolic compounds was also significant in both fruit and oil, although the low genotype × environment interaction allowed similar ranking of genotypes on the different environments. In summary, the high genotypic variance and the simplified procedure of the proposed methodology for fruit phenol evaluation seems to be convenient for breeding programs aiming at obtaining new cultivars with improved phenolic profile. PMID:29535752

Fruit Phenolic Profiling: A New Selection Criterion in Olive Breeding Programs.

PubMed

Pérez, Ana G; León, Lorenzo; Sanz, Carlos; de la Rosa, Raúl

2018-01-01

Olive growing is mainly based on traditional varieties selected by the growers across the centuries. The few attempts so far reported to obtain new varieties by systematic breeding have been mainly focused on improving the olive adaptation to different growing systems, the productivity and the oil content. However, the improvement of oil quality has rarely been considered as selection criterion and only in the latter stages of the breeding programs. Due to their health promoting and organoleptic properties, phenolic compounds are one of the most important quality markers for Virgin olive oil (VOO) although they are not commonly used as quality traits in olive breeding programs. This is mainly due to the difficulties for evaluating oil phenolic composition in large number of samples and the limited knowledge on the genetic and environmental factors that may influence phenolic composition. In the present work, we propose a high throughput methodology to include the phenolic composition as a selection criterion in olive breeding programs. For that purpose, the phenolic profile has been determined in fruits and oils of several breeding selections and two varieties ("Picual" and "Arbequina") used as control. The effect of three different environments, typical for olive growing in Andalusia, Southern Spain, was also evaluated. A high genetic effect was observed on both fruit and oil phenolic profile. In particular, the breeding selection UCI2-68 showed an optimum phenolic profile, which sums up to a good agronomic performance previously reported. A high correlation was found between fruit and oil total phenolic content as well as some individual phenols from the two different matrices. The environmental effect on phenolic compounds was also significant in both fruit and oil, although the low genotype × environment interaction allowed similar ranking of genotypes on the different environments. In summary, the high genotypic variance and the simplified procedure of the proposed methodology for fruit phenol evaluation seems to be convenient for breeding programs aiming at obtaining new cultivars with improved phenolic profile.

Complex enzyme hydrolysis releases antioxidative phenolics from rice bran.

PubMed

Liu, Lei; Wen, Wei; Zhang, Ruifen; Wei, Zhencheng; Deng, Yuanyuan; Xiao, Juan; Zhang, Mingwei

2017-01-01

In this study, phenolic profiles and antioxidant activity of rice bran were analyzed following successive treatment by gelatinization, liquefaction and complex enzyme hydrolysis. Compared with gelatinization alone, liquefaction slightly increased the total amount of phenolics and antioxidant activity as measured by ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays. Complex enzyme hydrolysis significantly increased the total phenolics, flavonoids, FRAP and ORAC by 46.24%, 79.13%, 159.14% and 41.98%, respectively, compared to gelatinization alone. Furthermore, ten individual phenolics present in free or soluble conjugate forms were also analyzed following enzymatic processing. Ferulic acid experienced the largest release, followed by protocatechuic acid and then quercetin. Interestingly, a major proportion of phenolics existed as soluble conjugates, rather than free form. Overall, complex enzyme hydrolysis releases phenolics, thus increasing the antioxidant activity of rice bran extract. This study provides useful information for processing rice bran into functional beverage rich in phenolics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structural Analysis of the Phenol-Responsive Sensory Domain of the Transcription Activator PoxR.

PubMed

Patil, Vinod Vikas; Park, Kwang-Hyun; Lee, Seung-Goo; Woo, Euijeon

2016-04-05

Positive phenol-degradative gene regulator (PoxR) is a σ(54)-dependent AAA+ ATPase transcription activator that regulates the catabolism of phenols. The PoxR sensory domain detects phenols and relays signals for the activation of transcription. Here we report the first structure of the phenol sensory domain bound to phenol and five derivatives. It exists as a tightly intertwined homodimer with a phenol-binding pocket buried inside, placing two C termini on the same side of the dimer. His102 and Trp130 interact with the hydroxyl group of the phenol in a cavity surrounded by rigid hydrophobic residues on one side and a flexible region on the other. Each monomer has a V4R fold with a unique zinc-binding site. A shift at the C-terminal helix suggests that there is a possible conformational change upon ligand binding. The results provide a structural basis of chemical effector binding for transcriptional regulation with broad implications for protein engineering. Copyright © 2016 Elsevier Ltd. All rights reserved.

ODC-Free Solvent Implementation for Phenolics Cleaning

NASA Technical Reports Server (NTRS)

Wurth, Laura; Biegert, Lydia; Lamont, DT; McCool, Alex (Technical Monitor)

2001-01-01

During phenolic liner manufacture, resin-impregnated (pre-preg) bias tape of silica, glass, or carbon cloth is tape-wrapped, cured, machined, and then wiped with 1,1,1 tri-chloroethane (TCA) to remove contaminants that may have been introduced during machining and handling. Following the TCA wipe, the machined surface is given a resin wet-coat and over-wrapped with more prepreg and cured. A TCA replacement solvent for these wiping operations must effectively remove both surface contaminants, and sub-surface oils and greases while not compromising the integrity of this interface. Selection of a TCA replacement solvent for phenolic over-wrap interface cleaning began with sub-scale compatibility tests with cured phenolics. Additional compatibility tests included assessment of solvent retention in machined phenolic surfaces. Results from these tests showed that, while the candidate solvent did not degrade the cured phenolics, it was retained in higher concentrations than TCA in phenolic surfaces. This effect was most pronounced with glass and silica cloth phenolics with steep ply angles relative to the wiped surfaces.

Synthesis, characterization, bioactivity and potential application of phenolic acid grafted chitosan: A review.

PubMed

Liu, Jun; Pu, Huimin; Liu, Shuang; Kan, Juan; Jin, Changhai

2017-10-15

In recent years, increasing attention has been paid to the grafting of phenolic acid onto chitosan in order to enhance the bioactivity and widen the application of chitosan. Here, we present a comprehensive overview on the recent advances of phenolic acid grafted chitosan (phenolic acid-g-chitosan) in many aspects, including the synthetic method, structural characterization, biological activity, physicochemical property and potential application. In general, four kinds of techniques including carbodiimide based coupling, enzyme catalyzed grafting, free radical mediated grafting and electrochemical methods are frequently used for the synthesis of phenolic acid-g-chitosan. The structural characterization of phenolic acid-g-chitosan can be determined by several instrumental methods. The physicochemical properties of chitosan are greatly altered after grafting. As compared with chitosan, phenolic acid-g-chitosan exhibits enhanced antioxidant, antimicrobial, antitumor, anti-allergic, anti-inflammatory, anti-diabetic and acetylcholinesterase inhibitory activities. Notably, phenolic acid-g-chitosan shows potential applications in many fields as coating agent, packing material, encapsulation agent and bioadsorbent. Copyright © 2017 Elsevier Ltd. All rights reserved.

LC-MS analysis of phenolic compounds and antioxidant activity of buckwheat at different stages of malting.

PubMed

Terpinc, Petra; Cigić, Blaž; Polak, Tomaž; Hribar, Janez; Požrl, Tomaž

2016-11-01

The impact of malting on the profile of the phenolic compounds and the antioxidant properties of two buckwheat varieties was investigated. The highest relative increases in phenolic compounds were observed for isoorientin, orientin, and isovitexin, which are consequently major inducible phenolic compounds during malting. Only a minor relative increase was observed for the most abundant phenolic compound, rutin. The radical-scavenging activity of buckwheat seeds was evaluated using ABTS and DPPH assays. A considerable increase in total phenolic compounds and higher antioxidant activity were observed after 64h of germination, whereas kilning resulted in decreased total phenolic compounds and antioxidant activity. Higher antioxidant activities for extracts were found for buffered solvents than for pure methanol and water. Changes in the composition of the phenolic compounds and increased antioxidant content were confirmed by several methods, indicating that buckwheat malt can be used as a food rich in antioxidants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of different cellulases on the release of phenolic acids from rice straw during saccharification.

PubMed

Xue, Yiyun; Wang, Xiahui; Chen, Xingxuan; Hu, Jiajun; Gao, Min-Tian; Li, Jixiang

2017-06-01

Effects of different cellulases on the release of phenolic acids from rice straw during saccharification were investigated in this study. All cellulases tested increased the contents of phenolic acids during saccharification. However, few free phenolic acids were detected, as they were present in conjugated form after saccharification when the cellulases from Trichoderma reesei, Trichoderma viride and Aspergillus niger were used. On the other hand, phenolic acids were present in free form when the Acremonium cellulolyticus cellulase was used. Assays of enzyme activity showed that, besides high cellulase activity, the A. cellulolyticus cellulase exhibited high feruloyl esterase (FAE) activity. A synergistic interaction between FAE and cellulase led to the increase in free phenolic acids, and thus an increase in antioxidative and antiradical activities of the phenolic acids. Moreover, a cost estimation demonstrated the feasibility of phenolic acids as value-added products to reduce the total production cost of ethanol. Copyright © 2017 Elsevier Ltd. All rights reserved.

Solid state fermentation of Trichoderma viride for enhancement phenolic content, antioxidant and antimicrobial activities in ginger.

PubMed

Saleh, Rashad M; Kabli, Saleh A; Al-Garni, Saleh M; Al-Ghamdi, Maryam A; Abdel-Aty, Azza M; Mohamed, Saleh A

2018-05-04

The phenolic content of methanolic and water extracts of ginger fermented by Trichoderma spp. during solid state fermentation (SSF) was detected as compared with unfermented ginger. The total phenolic content of fermented ginger increased several times. The highest phenolic content of ginger was detected after SSF by T. viride. The optimal physiological conditions for the maximum production of the phenolic content and β-glucosidase activity of fermented ginger by T. viride were detected at day 7 incubation, pH 6.0, 30°C and 30% moisture. There are consistent between the maximum production of β-glucosidase and phenolic content. The SSF of ginger by T. viride greatly enhanced the antioxidant potency of phenolic compounds by using DPPH and ABTS assays. Potent antibacterial activity was appeared by phenolic compounds of fermented ginger against all the tested human-pathogenic bacteria. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Phenolic content and antioxidant and antimutagenic activities in tomato peel, seeds, and byproducts.

PubMed

Valdez-Morales, Maribel; Espinosa-Alonso, Laura Gabriela; Espinoza-Torres, Libia Citlali; Delgado-Vargas, Francisco; Medina-Godoy, Sergio

2014-06-11

The phenolic content and antioxidant and antimutagenic activities from the peel and seeds of different tomato types (grape, cherry, bola and saladette type), and simulated tomato industrial byproducts, were studied. Methanolic extracts were used to quantify total phenolic content, groups of phenolic compounds, antioxidant activities, and the profile of phenolic compounds (by HPLC-DAD). Antimutagenic activity was determined by Salmonella typhimurium assay. The total phenolic content and antioxidant activity of tomato and tomato byproducts were comparable or superior to those previously reported for whole fruit and tomato pomace. Phenolic compounds with important biological activities, such as caffeic acid, ferulic acid, chlorogenic acids, quercetin-3-β-O-glycoside, and quercetin, were quantified. Differences in all phenolic determinations due to tomato type and part of the fruit analyzed were observed, peel from grape type showing the best results. Positive antimutagenic results were observed in all samples. All evaluated materials could be used as a source of potential nutraceutical compounds.

Phenolic profile and effect of growing area on Pistacia lentiscus seed oil.

PubMed

Mezni, Faten; Slama, Awatef; Ksouri, Riadh; Hamdaoui, Ghaith; Khouja, Mohamed Larbi; Khaldi, Abdelhamid

2018-08-15

In this investigation, we aimed to study, for the first time, the phenolic composition of Pistacia lentiscus seed oils from different growing areas. Extraction of the phenolic fraction from oils was done by methanol/water. Phenolic profiles were determined using chromatographic analysis by High Performance Liquid Chromatography (HPLC-DAD/MSD) and its quantification was done using an internal standard which is unidentified in the studied oil (syringic acid). Forty phenolic compounds were quantified and only eighteen of them were identified. The eight studied oils showed different phenolic profiles. The total phenols amount varied from 538.03 mg/kg oil in Jbel Masour oils to 4260.57 mg/kg oil in oils from Kef Erraai. The highest amount of secoiridoids was reached by Bouchoucha oil containing 366.71 mg/kg oil of Oleuropein aglycon. Oils from Kef Erraai locality contained the highest concentrations in flavonols (377.44 mg/kg oil) and in phenolic acids (2762.67 mg/kg oil). Copyright © 2018 Elsevier Ltd. All rights reserved.

Determination of the major phenolic compounds in pomegranate juices by HPLC−DAD−ESI-MS.

PubMed

Gómez-Caravaca, Ana María; Verardo, Vito; Toselli, Moreno; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto; Caboni, Maria Fiorenza

2013-06-05

Traditionally, pomegranate (Punica granatum L.) has been consumed as fresh fruit or as pomegranate juice. In this study, the main phenolic compounds of 12 pomegranate varieties and 5 pomegranate clones were determined by HPLC−DAD−ESI-MS. Two chromatographic methods with a fused-core C18 column and a classical HPLC system were developed. Thirteen anthocyanins and fourteen other phenolic compounds were determined in the pomegranate juices. As far as we are concerned, a new flavonol-glycoside, phellatin or its isomer amurensin, has been tentatively identified for the first time in pomegranate juices. Total phenolic content ranged from 580.8 to 2551.3 mg/L of pomegranate juice. Anthocyanins varied between 20 to 82% of total phenolic content. Flavonoids were 1.6-23.6% of total phenolic compounds, while phenolic acids and ellagitannins were in the range 16.4-65.8%. The five clones reported a phenolic content comparable with that of the other pomegranate samples.

Physiological and functional diversity of phenol degraders isolated from phenol-grown aerobic granules: Phenol degradation kinetics and trichloroethylene co-metabolic activities.

PubMed

Zhang, Yi; Tay, Joo Hwa

2016-03-15

Aerobic granule is a novel form of microbial aggregate capable of degrading toxic and recalcitrant substances. Aerobic granules have been formed on phenol as the growth substrate, and used to co-metabolically degrade trichloroethylene (TCE), a synthetic solvent not supporting aerobic microbial growth. Granule formation process, rate limiting factors and the comprehensive toxic effects of phenol and TCE had been systematically studied. To further explore their potential at the level of microbial population and functions, phenol degraders were isolated and purified from mature granules in this study. Phenol and TCE degradation kinetics of 15 strains were determined, together with their TCE transformation capacities and other physiological characteristics. Isolation in the presence of phenol and TCE exerted stress on microbial populations, but the procedure was able to preserve their diversity. Wide variation was found with the isolates' kinetic behaviors, with the parameters often spanning 3 orders of magnitude. Haldane kinetics described phenol degradation well, and the isolates exhibited actual maximum phenol-dependent oxygen utilization rates of 9-449 mg DO g DW(-1) h(-1), in phenol concentration range of 4.8-406 mg L(-1). Both Michaelis-Menten and Haldane types were observed for TCE transformation, with the actual maximum rate of 1.04-21.1 mg TCE g DW(-1) h(-1) occurring between TCE concentrations of 0.42-4.90 mg L(-1). The TCE transformation capacities and growth yields on phenol ranged from 20-115 mg TCE g DW(-1) and 0.46-1.22 g DW g phenol(-1), respectively, resulting in TCE transformation yields of 10-70 mg TCE g phenol(-1). Contact angles of the isolates were between 34° and 82°, suggesting both hydrophobic and hydrophilic cell surface. The diversity in the isolates is a great advantage, as it enables granules to be versatile and adaptive under different operational conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Verification of the electron/proton coupled mechanism for phenolic H-atom transfer using a triplet π,π ∗ carbonyl

NASA Astrophysics Data System (ADS)

Yamaji, Minoru; Oshima, Juro; Hidaka, Motohiko

2009-06-01

Evidence for the coupled electron/proton transfer mechanism of the phenolic H-atom transfer between triplet π,π ∗ 3,3'-carbonylbis(7-diethylaminocoumarin) and phenol derivatives is obtained by using laser photolysis techniques. It was confirmed that the quenching rate constants of triplet CBC by phenols having positive Hammett constants do not follow the Rehm-Weller equation for electron transfer while those by phenols with negative Hammett constants do it. From the viewpoint of thermodynamic parameters for electron transfer, the crucial factors for phenolic H-atom transfer to π,π ∗ triplet are discussed.

A characterization of the two-step reaction mechanism of phenol decomposition by a Fenton reaction

NASA Astrophysics Data System (ADS)

Valdés, Cristian; Alzate-Morales, Jans; Osorio, Edison; Villaseñor, Jorge; Navarro-Retamal, Carlos

2015-11-01

Phenol is one of the worst contaminants at date, and its degradation has been a crucial task over years. Here, the decomposition process of phenol, in a Fenton reaction, is described. Using scavengers, it was observed that decomposition of phenol was mainly influenced by production of hydroxyl radicals. Experimental and theoretical activation energies (Ea) for phenol oxidation intermediates were calculated. According to these Ea, phenol decomposition is a two-step reaction mechanism mediated predominantly by hydroxyl radicals, producing a decomposition yield order given as hydroquinone > catechol > resorcinol. Furthermore, traces of reaction derived acids were detected by HPLC and GS-MS.

Inhibitory effects of benzimidazole containing new phenolic Mannich bases on human carbonic anhydrase isoforms hCA I and II.

PubMed

Gul, Halise Inci; Yazici, Zehra; Tanc, Muhammet; Supuran, Claudiu T

2016-12-01

New phenolic mono and bis Mannich bases incorporating benzimidazole, such as 2-(aminomethyl)-4-(1H-benzimidazol-2-yl)phenol and 2,6-bis(aminomethyl)-4-(1H-benzimidazol-2-yl)phenol were synthesized starting from 4-(1H-benzimidazol-2-yl)phenol. Amines used for the synthesis included dimethylamine, pyrrolidine, piperidine, N-methylpiperazine and morpholine. The CA inhibitory properties of these compounds were tested on the human carbonic anhydrase (CA, EC 4.2.1.1) isoforms hCA I and hCA II. These new compounds, as many phenols show moderate CA inhibitory properties.

Antibacterial activity of sphagnum acid and other phenolic compounds found in Sphagnum papillosum against food-borne bacteria.

PubMed

Mellegård, H; Stalheim, T; Hormazabal, V; Granum, P E; Hardy, S P

2009-07-01

To identify the phenolic compounds in the leaves of Sphagnum papillosum and examine their antibacterial activity at pH appropriate for the undissociated forms. Bacterial counts of overnight cultures showed that whilst growth of Staphylococcus aureus 50084 was impaired in the presence of milled leaves, the phenol-free fraction of holocellulose of S. papillosum had no bacteriostatic effect. Liquid chromatography-mass spectrometry analysis of an acetone-methanol extract of the leaves detected eight phenolic compounds. Antibacterial activity of the four dominating phenols specific to Sphagnum leaves, when assessed in vitro as minimal inhibitory concentrations (MICs), were generally >2.5 mg ml(-1). MIC values of the Sphagnum-specific compound 'sphagnum acid' [p-hydroxy-beta-(carboxymethyl)-cinnamic acid] were >5 mg ml(-1). No synergistic or antagonistic effects of the four dominating phenols were detected in plate assays. Sphagnum-derived phenolics exhibit antibacterial activity in vitro only at concentrations far in excess of those found in the leaves. We have both identified the phenolic compounds in S. papillosum and assessed their antibacterial activity. Our data indicate that phenolic compounds in isolation are not potent antibacterial agents and we question their potency against food-borne pathogens.

Effect of nutrients on Chlorella pyrenoidosa for treatment of phenolic effluent of coal gasification plant.

PubMed

Stephen, Dayana Priyadharshini; Ayalur, Bakthavatsalam Kannappan

2017-05-01

The ability of Chlorella pyrenoidosa, a freshwater microalga, to degrade phenolic effluent of coal-based producer gas plant under ambient conditions was investigated. C. pyrenoidosa was able to grow in high-strength phenolic effluent. Major contaminant present in the effluent was phenol (C 6 H 5 OH). The effluent has 1475.3 ± 68 mg/L of initial total phenolic concentration. The effect of nutrients used for algal cultivation in phenol degradation was analyzed by inoculating four different concentrations, viz.,1, 2, 3, and 4 g of wet biomass/L of raw effluent of C. pyrenoidosa mixed with effluent into two batches (with and without nutrients). C. pyrenoidosa was able to degrade more than 95% of the phenol (C 6 H 5 OH) concentration with the algal concentrations of 3 and 4 g/L when supplemented with nutrients. With effluent devoid of nutrients, the average percent reduction in total phenolic compounds was observed to a maximum of 46%. No physical changes in the C. pyrenoidosa were observed during degradation. C. pyrenoidosa was able to consume the organic carbon present in the phenolic compounds as carbon source for its growth despite the inorganic carbon supplemented externally.

Standardization of the carbon-phenolic materials and processes. Vol. 1: Experimental studies

NASA Technical Reports Server (NTRS)

Hall, William B.

1988-01-01

Carbon-phenolic composite materials are used as ablative material in the solid rocket motor nozzle of the Space Shuttle. The nozzle is lined with carbon cloth-phenolic resin composites. The nominal effects of the completely consumed solid propellant on the carbon-phenolic material are given. The extreme heat and erosion of the burning propellant are controlled by the carbon-phenolic composite by ablation, the heat and mass transfer process in which a large amount of heat is absorbed by sacrificially removing material from the nozzle surface. Phenolic materials ablate with the initial formation of a char. The depth of the char is a function of the heat conduction coefficient of the composite. The char layer is a very poor heat conductor so it protects the underlying phenolic composite from the high heat of the burning propellant. The nozzle component ablative liners (carbon cloth-phenolic composites) are tape wrapped, hydroclave and/or autoclave cured, machined, and assembled. The tape consists of a prepreg broadcloth. The materials flow sheet for the nozzle ablative liners is shown. The prepreg is a three component system: phenolic resin, carbon cloth, and carbon filler. This is Volume 1 of two, Experimental Studies.

Remediation of phenol-contaminated soil by a bacterial consortium and Acinetobacter calcoaceticus isolated from an industrial wastewater treatment plant.

PubMed

Cordova-Rosa, S M; Dams, R I; Cordova-Rosa, E V; Radetski, M R; Corrêa, A X R; Radetski, C M

2009-05-15

Time-course performance of a phenol-degrading indigenous bacterial consortium, and of Acinetobacter calcoaceticus var. anitratus, isolated from an industrial coal wastewater treatment plant was evaluated. This bacterial consortium was able to survive in the presence of phenol concentrations as high as 1200mgL(-1) and the consortium was more fast in degrading phenol than a pure culture of the A. calcoaceticus strain. In a batch system, 86% of phenol biodegradation occurred in around 30h at pH 6.0, while at pH 3.0, 95.2% of phenol biodegradation occurred in 8h. A high phenol biodegradation (above 95%) by the mixed culture in a bioreactor was obtained in both continuous and batch systems, but when test was carried out in coke gasification wastewater, no biodegradation was observed after 10 days at pH 9-11 for both pure strain or the isolated consortium. An activated sludge with the same bacterial consortium characterized above was mixed with a textile sludge-contaminated soil with a phenol concentration of 19.48mgkg(-1). After 20 days of bioaugmentation, the remanescent phenol concentration of the sludge-soil matrix was 1.13mgkg(-1).

Complex Enzyme-Assisted Extraction Releases Antioxidative Phenolic Compositions from Guava Leaves.

PubMed

Wang, Lu; Wu, Yanan; Liu, Yan; Wu, Zhenqiang

2017-09-30

Phenolics in food and fruit tree leaves exist in free, soluble-conjugate, and insoluble-bound forms. In this study, in order to enhance the bioavailability of insoluble-bound phenolics from guava leaves (GL), the ability of enzyme-assisted extraction in improving the release of insoluble-bound phenolics was investigated. Compared to untreated GL, single xylanase-assisted extraction did not change the composition and yield of soluble phenolics, whereas single cellulase or β -glucosidase-assisted extraction significantly enhanced the soluble phenolics content of PGL. However, complex enzyme-assisted extraction (CEAE) greatly improved the soluble phenolics content, flavonoids content, ABTS, DPPH, and FRAP by 103.2%, 81.6%, 104.4%, 126.5%, and 90.3%, respectively. Interestingly, after CEAE, a major proportion of phenolics existed in the soluble form, and rarely in the insoluble-bound form. Especially, the contents of quercetin and kaempferol with higher bio-activity were enhanced by 3.5- and 2.2-fold, respectively. More importantly, total soluble phenolics extracts of GL following CEAE exhibited the highest antioxidant activity and protective effect against supercoiled DNA damage. This enzyme-assisted extraction technology can be useful for extracting biochemical components from plant matrix, and has good potential for use in the food and pharmaceutical industries.

In-Depth Two-Year Study of Phenolic Profile Variability among Olive Oils from Autochthonous and Mediterranean Varieties in Morocco, as Revealed by a LC-MS Chemometric Profiling Approach

PubMed Central

Bajoub, Aadil; Medina-Rodríguez, Santiago; Olmo-García, Lucía; Ajal, El Amine; Monasterio, Romina P.; Hanine, Hafida; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría

2016-01-01

Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars (“Picholine Marocaine”, “Dahbia”, “Haouzia” and “Menara”), and nine Mediterranean varieties recently introduced in Morocco (“Arbequina”, “Arbosana”, “Cornicabra”, “Frantoio”, “Hojiblanca”, “Koroneiki”, “Manzanilla”, “Picholine de Languedoc” and “Picual”), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils. PMID:28036024

How to Plant Apple Trees to Reduce Replant Disease in Apple Orchard: A Study on the Phenolic Acid of the Replanted Apple Orchard

PubMed Central

Yin, Chengmiao; Xiang, Li; Wang, Gongshuai; Wang, Yanfang; Shen, Xiang; Chen, Xuesen; Mao, Zhiquan

2016-01-01

Apple replant disease (ARD) is an important problem in the production of apple. The phenolic acid is one of the causes of ARD. How phenolic acid affects the ARD was not well known. In this study, we analyzed the type, concentration and annual dynamic variation of phenolic acid in soil from three replanted apple orchards using an accelerated solvent extraction system with high performance liquid chromatography (ASE-HPLC). We found that the type and concentration of phenolic acid were significantly differed among different seasons, different sampling positions and different soil layers. Major types of phenolic acid in three replanted apple orchards were phlorizin, benzoic acid and vanillic aldehyde. The concentration of phenolic acid was highest in the soil of the previous tree holes and it was increased from the spring to autumn. Moreover, phenolic acid was primarily distributed in 30–60 cm soil layer in the autumn, while it was most abundant in 0–30 cm soil layer in the spring. Our results suggest that phlorizin, benzoic acid and vanillic aldehyde may be the key phenolic acid that brought about ARD in the replanted apple orchard. PMID:27907081

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gill, D.P.; Kempen, R.R.; Nash, J.B.

It has recently been suggested that the primary myelotoxic species generated from benzene is not produced directly from the parent compound, but from phenol or an even later metabolite. Several compounds that alter the activities of microsomal oxidative and conjugating enzymes were studied for their effects on benzene's myelotoxicity and metabolism. Phenobarbital (PB) protected animals from leucopnia and increased both to total amount of phenol as well as the amount of unconjugated phenol excreted in the urine. SKF-525A had no effect on the leucopenia, whereas it reduced the conversion of benzene to phenol without changing the excretion of unconjugated phenol.more » 3-Methylcholanthrene also did not prevent the leucopenia, but it did increase the conversion of benzene to phenol and the amount of unconjugated phenol excreted during the first days of the experiment. These data indicate that the early phases of benzene's metabolism may be modulated by the drug pretreatments employed, but myelotoxicity was abated only by PB. We conclude that the marrow effect of benzene is due to a metabolic product other than phenol and, furthermore that the formation of this toxic principle is not strictly dependent on the rate of phenol production.« less

Comparison of the free and bound phenolic profiles and cellular antioxidant activities of litchi pulp extracts from different solvents

PubMed Central

2014-01-01

Background The phenolic contents and antioxidant activities of fruits could be underestimated if the bound phenolic compounds are not considered. In the present study, the extraction efficiencies of various solvents were investigated in terms of the total content of the free and bound phenolic compounds, as well as the phenolic profiles and antioxidant activities of the extracts. Methods Five different solvent mixtures were used to extract the free phenolic compounds from litchi pulp. Alkaline and acidic hydrolysis methods were compared for the hydrolysis of bound phenolic compounds from litchi pulp residue. The phenolic compositions of the free and bound fractions from the litchi pulp were identified using HPLC-DAD. The antioxidant activities of the litchi pulp extracts were determined by oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA) assays. Results Of the solvents tested, aqueous acetone extracted the largest amount of total free phenolic compounds (210.7 mg GAE/100 g FW) from litchi pulp, followed sequentially by aqueous mixtures of methanol, ethanol and ethyl acetate, and water itself. The acid hydrolysis method released twice as many bound phenolic compounds as the alkaline hydrolysis method. Nine phenolic compounds were detected in the aqueous acetone extract. In contrast, not all of these compounds were found in the other four extracts. The classification and content of the bound phenolic compounds released by the acid hydrolysis method were higher than those achieved by the alkaline hydrolysis. The aqueous acetone extract showing the highest ORAC value (3406.9 μmol TE/100 g FW) for the free phenolic extracts. For the CAA method, however, the aqueous acetone and methanol extracts (56.7 and 55.1 μmol QE/100 g FW) showed the highest levels of activity of the five extracts tested. The ORAC and CAA values of the bound phenolic compounds obtained by acid hydrolysis were 2.6- and 1.9-fold higher than those obtained using the alkaline hydrolysis method. Conclusions The free and bound phenolic contents and profiles and antioxidant activities of the extracts were found to be dependent on the extraction solvent used. Litchi exhibited good cellular antioxidant activity and could be a potentially useful natural source of antioxidants. PMID:24405977

40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

Predicting the reactivity of adhesive starting materials

Treesearch

Anthony H. Conner

1999-01-01

Phenolic compounds are important in the production of bonded-wood products. Phenolic compounds in addition to phenol and resorcinol are potential alternative feedstocks for producing adhesives. The reactivity of a wide variety of phenolic compounds with formaldehyde was investigated using semi-empirical and ab initio computational chemistry methods...

40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

Substituent effect of phenolic aldehyde inhibition on alcoholic fermentation by Saccharomyces cerevisiae

Treesearch

Rui Xie; Maobing Tu; Thomas Elder

2016-01-01

Phenolic compounds significantly inhibit microbial fermentation of biomass hydrolysates. To understand thequantitative structure-inhibition relationship of phenolic aldehydes on alcoholic fermentation, the effect of 11 differentsubstituted benzaldehydes on the final ethanol yield was examined. The results showed that the degree of phenolic...

40 CFR 721.5908 - Modified phenolic resin (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified phenolic resin (generic). 721... Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as modified phenolic resin (PMN P...

40 CFR 721.5905 - Modified phenolic resin (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified phenolic resin (generic). 721... Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a modified phenolic resin (PMN...

40 CFR 721.3800 - Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...

Code of Federal Regulations, 2010 CFR

2010-07-01

... polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. 721.3800 Section 721.3800... Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. (a... generically as formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...

IUS (Inertial Upper Stage)/SRM-2 Nozzle Thermal Assessment

DTIC Science & Technology

1984-12-01

design where this could occur:,(see figure 1) 1)(1) The nose cap carbon phenolic to silica phenolic bond surface where temperatures were p:edicted to...contact only with the carbon phenolic r.ose cap and the carbon- carbon integral throat entrance. Although the carbon phenolic is impervious to gas flow...between the housing and silica phenolic liner. After the baseline (BL-l) motor firing, inspection of the gratoil seal area revealed erosion and a hole

Oxidative stability, phenolic compounds and antioxidant potential of a virgin olive oil enriched with natural bioactive compounds.

PubMed

Delgado-Adámez, Jonathan; Baltasar, M Nieves Franco; Yuste, María Concepción Ayuso; Martín-Vertedor, Daniel

2014-01-01

The aim of this research was to evaluate strategies for the development of a virgin olive oil (VOO) enriched with aqueous extracts of olive leaf and cake to increase the necessary dose in the diet of phenolic compounds with a natural product, as phenolic compounds are involved on the healthy properties of olive oil. Different extraction procedures were evaluated with the aim of increasing the phenol content and antioxidant potential of extracts of olive leaf and cake. As leaves extract presented a higher total phenolic content, it was characterized in order to determine its phenolic profile, and was employed to enrich VOO. Diverse procedures were used to prepare enriched VOO with the leaves extract, and finally the effects of phenol enrichment were evaluated based on the antioxidant potential and oxidative stability of the prepared phenol-enriched virgin olive oils. These enriched VOOs increased significantly the content in phenolic compounds, antioxidant potential and oxidative stability 40, 4 and 1.5 fold more, respectively, than the Control oil. Furthermore, the addition of lecithin had a positive effect both on the phenolic compounds content, and on the antioxidant potential of the oils. Besides, the use of the olive leaves extract, with and without lecithin respectively, supposes a strategy potential for reducing the harmful effects that inflicts long-term preservation of VOOs and its possible deterioration.

Comparative transcriptomics elucidates adaptive phenol tolerance and utilization in lipid-accumulating Rhodococcus opacus PD630

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoneda, Aki; Henson, William R.; Goldner, Nicholas K.

Lignin-derived (e.g. phenolic) compounds can compromise the bioconversion of lignocellulosic biomass to fuels and chemicals due to their toxicity and recalcitrance. The lipid-accumulating bacterium Rhodococcus opacus PD630 has recently emerged as a promising microbial host for lignocellulose conversion to value-added products due to its natural ability to tolerate and utilize phenolics. To gain a better understanding of its phenolic tolerance and utilization mechanisms, we adaptively evolved R. opacus over 40 passages using phenol as its sole carbon source (up to 373% growth improvement over wild-type), and extensively characterized two strains from passages 33 and 40. The two adapted strains showedmore » higher phenol consumption rates (~20 mg/l/h) and ~2-fold higher lipid production from phenol than the wild-type strain.Whole-genome sequencing and comparative transcriptomics identified highly-upregulated degradation pathways and putative transporters for phenol in both adapted strains, highlighting the important linkage between mechanisms of regulated phenol uptake, utilization, and evolved tolerance. Our study shows that the R. opacus mutants are likely to use their transporters to import phenol rather than export them, suggesting a new aromatic tolerance mechanism. The identified tolerance genes and pathways are promising candidates for future metabolic engineering in R. opacus for improved lignin conversion to lipid-based products.« less

Comparative transcriptomics elucidates adaptive phenol tolerance and utilization in lipid-accumulating Rhodococcus opacus PD630

DOE PAGES

Yoneda, Aki; Henson, William R.; Goldner, Nicholas K.; ...

2016-02-02

Lignin-derived (e.g. phenolic) compounds can compromise the bioconversion of lignocellulosic biomass to fuels and chemicals due to their toxicity and recalcitrance. The lipid-accumulating bacterium Rhodococcus opacus PD630 has recently emerged as a promising microbial host for lignocellulose conversion to value-added products due to its natural ability to tolerate and utilize phenolics. To gain a better understanding of its phenolic tolerance and utilization mechanisms, we adaptively evolved R. opacus over 40 passages using phenol as its sole carbon source (up to 373% growth improvement over wild-type), and extensively characterized two strains from passages 33 and 40. The two adapted strains showedmore » higher phenol consumption rates (~20 mg/l/h) and ~2-fold higher lipid production from phenol than the wild-type strain.Whole-genome sequencing and comparative transcriptomics identified highly-upregulated degradation pathways and putative transporters for phenol in both adapted strains, highlighting the important linkage between mechanisms of regulated phenol uptake, utilization, and evolved tolerance. Our study shows that the R. opacus mutants are likely to use their transporters to import phenol rather than export them, suggesting a new aromatic tolerance mechanism. The identified tolerance genes and pathways are promising candidates for future metabolic engineering in R. opacus for improved lignin conversion to lipid-based products.« less

Kinetic studies on the removal of phenol by MBBR from saline wastewater.

PubMed

Ahmadi, Mehdi; Jaafarzadeh, Neamat; Rahmat, Zeinab Ghaed; Babaei, Ali Akbar; Alavi, Nadali; Baboli, Zeinab; Niri, Mehdi Vosoughi

2017-01-01

Phenols are chemical compounds which are included in the high priority of pollutants by environmental protection agency (USEPA). The presence of high concentrations of phenols in wastewaters like oil refineries, petrochemical plants, olive oil, pesticide production and oil field operations contain high soluble solids (TDS) and in an olive oil plant, wastewater is acidic, high salty and phenol concentrations are in the range of 0.1- 1%. Kinetic parameters were calculated according to Monod, Modified Stover- Kincannon, Hamoda and Haldane models. The influence of different initial phenol concentrations on the biodegradation rate was performed. The concentrations of phenol varied from 0 to 500 mg / l. The value of K i in saline phenolic wastewater in attached growth systems was higher than suspended growth systems that represented a higher phenol inhibition in suspended growth systems. It was obvious that the best model fitting the obtained data are Hamoda model and the Modified Stover-Kincannon model, having highest R 2 values of 0.991 and 1, respectively. The value of K i in saline phenolic wastewater in attached growth system was higher than suspended growth systems which represented a higher phenol inhibition in suspended growth systems. Hamoda model and the Modified Stover-Kincannon model having highest R2 value of 0.991 and 1, respectively, and also predicting reasonable kinetic coefficient values.

Substrate inhibition kinetics of phenol biodegradation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goudar, C.T.; Ganji, S.H.; Pujar, B.G.

Phenol biodegradation was studied in batch experiments using an acclimated inoculum and initial phenol concentrations ranging from 0.1 to 1.3 g/L. Phenol depletion an associated microbial growth were monitored over time to provide information that was used to estimate the kinetics of phenol biodegradation. Phenol inhibited biodegradation at high concentrations, and a generalized substrate inhibition model based on statistical thermodynamics was used to describe the dynamics of microbial growth in phenol. For experimental data obtained in this study, the generalized substrate inhibition model reduced to a form that is analogous to the Andrews equation, and the biokinetic parameters {micro}{sub max},more » maximum specific growth; K{sub s}, saturation constant; and K{sub i}, inhibition constant were estimated as 0.251 h{sup {minus}1}, 0.011 g/L, and 0.348 g/L, respectively, using a nonlinear least squares technique. Given the wide variability in substrate inhibition models used to describe phenol biodegradation, an attempt was made to justify selection of particular model based on theoretical considerations. Phenol biodegradation data from nine previously published studies were used in the generalized substrate inhibition model to determine the appropriate form of the substrate inhibition model. In all nine cases, the generalized substrate inhibition model reduced to a form analogous to the Andrews equation suggesting the suitability of the Andrews equation to describe phenol biodegradation data.« less

Association between Dietary Phenolic Acids and Hypertension in a Mediterranean Cohort.

PubMed

Godos, Justyna; Sinatra, Dario; Blanco, Isabella; Mulè, Serena; La Verde, Melania; Marranzano, Marina

2017-09-27

Certain foods rich in phenolic acids have been shown to reduce the risk of hypertension, but evidence from epidemiological studies focused on dietary phenolic acid intake is scarce. The aim of this study was to determine the association between dietary phenolic acid intake, as well as their major food sources, and hypertension in a Mediterranean cohort. Demographic and dietary data of 2044 adults living in Southern Italy were collected. Food frequency questionnaires and Phenol-Explorer were used to calculate dietary intake of polyphenols. Multivariate logistic regression analyses were used to test associations. The mean intake of total phenolic acids in the cohort was 362.6 mg/day. Individuals in the highest quartile of phenolic acid intake (median intake = 522.2 mg/day) were less likely to have hypertension (OR (odds ratio) = 0.68, 95% CI (confidence interval): 0.46, 1.00). When taking into account individual subclasses of phenolic acids, only hydroxyphenylacetic acid was inversely associated with hypertension (highest vs. lowest quartile, OR = 0.63, 95% CI: 0.40, 0.96). Among dietary sources of phenolic acids considered in the analysis, only beer was significantly inversely associated with hypertension (highest vs. lowest quartile, OR = 0.32, 95% CI: 0.15, 0.68). The findings of this study suggest that dietary phenolic acids may be inversely associated with hypertension, irrespectively of their dietary source.

Synergistic anti-Campylobacter jejuni activity of fluoroquinolone and macrolide antibiotics with phenolic compounds

PubMed Central

Oh, Euna; Jeon, Byeonghwa

2015-01-01

The increasing resistance of Campylobacter to clinically important antibiotics, such as fluoroquinolones and macrolides, is a serious public health problem. The objective of this study is to investigate synergistic anti-Campylobacter jejuni activity of fluoroquinolones and macrolides in combination with phenolic compounds. Synergistic antimicrobial activity was measured by performing a checkerboard assay with ciprofloxacin and erythromycin in the presence of 21 phenolic compounds. Membrane permeability changes in C. jejuni by phenolic compounds were determined by measuring the level of intracellular uptake of 1-N-phenylnaphthylamine (NPN). Antibiotic accumulation assays were performed to evaluate the level of ciprofloxacin accumulation in C. jejuni. Six phenolic compounds, including p-coumaric acid, sinapic acid, caffeic acid, vanillic acid, gallic acid, and taxifolin, significantly increased the susceptibility to ciprofloxacin and erythromycin in several human and poultry isolates. The synergistic antimicrobial effect was also observed in ciprofloxacin- and erythromycin-resistant C. jejuni strains. The phenolic compounds also substantially increased membrane permeability and antibiotic accumulation in C. jejuni. Interestingly, some phenolic compounds, such as gallic acid and taxifolin, significantly reduced the expression of the CmeABC multidrug efflux pump. Phenolic compounds increased the NPN accumulation in the cmeB mutant, indicating phenolic compounds may affect the membrane permeability. In this study, we successfully demonstrated that combinational treatment of C. jejuni with antibiotics and phenolic compounds synergistically inhibits C. jejuni by impacting both antimicrobial influx and efflux. PMID:26528273

Selective Detoxification of Phenols by Pichia pastoris and Arabidopsis thaliana Heterologously Expressing the PtUGT72B1 from Populus trichocarpa

PubMed Central

Xu, Zhi-Sheng; Lin, Ya-Qiu; Xu, Jing; Zhu, Bo; Zhao, Wei; Peng, Ri-He; Yao, Quan-Hong

2013-01-01

Phenols are present in the environment and commonly in contact with humans and animals because of their wide applications in many industries. In a previous study, we reported that uridine diphosphate-glucose-dependent glucosyltransferase PtUGT72B1 from Populus trichocarpa has high activity in detoxifying trichlorophenol by conjugating glucose. In this study, more experiments were performed to determine the substrate specificity of PtUGT72B1 towards phenolic compounds. Among seven phenols tested, three were glucosylated by PtUGT72B1 including phenol, hydroquinone, and catechol. Transgenic Arabidopsis plants expressing the enzyme PtUGT72B1 showed higher resistance to hydroquinone and catechol but more sensitivity to phenol than wild type plants. Transgenic Pichia pastoris expressing PtUGT72B1 showed enhanced resistance to all three phenols. Compared with wild type Arabidopsis plants, transgenic Arabidopsis plants showed higher removal efficiencies and exported more glucosides of phenol, phenyl β-D-glucopyranoside, to the medium after cultured with the three phenols. Protein extracts from transgenic Arabidopsis plants showed enhanced conjugating activity towards phenol, hydroquinone and catechol. PtUGT72B1 showed much higher expression level in Pichia pastoris than in Arabidopsis plants. Kinetic analysis of the PtUGT72B1 was also performed. PMID:23840543

Phenolic wastewater treatment through extractive recovery coupled with biodegradation in a two-phase partitioning membrane bioreactor.

PubMed

Praveen, Prashant; Loh, Kai-Chee

2015-12-01

A two-phase partitioning membrane bioreactor (TPPMB) was designed and operated for treatment of high strength phenolic wastewater through extraction/stripping and concomitant biodegradation. Tributyl phosphate dissolved in kerosene was used as the organic phase, sodium hydroxide as the stripping phase and Pseudomonas putida for biodegradation. In a semi-dispersive approach, organic phase dispersed in the stripping solution was contacted with wastewater through semi-permeable membranes for removal of phenol from wastewater, while the microorganisms were inoculated directly into the wastewater for biodegradation. The TPPMB exhibited high phenol removal rates, and phenol concentrations of 1000-3000mg/L were reduced to undetected amounts within 2-4h. Up to 80% phenol was recovered through extraction, while the remaining was metabolized by the microorganisms. Phenol recovery in the TPPMB was enhanced by increasing the mass transfer rate of phenol through the membranes, and it was also estimated that phenol diffusion through the aqueous boundary layer on the tube side was the rate limiting step. The flexibility in adjusting inoculation time in the TPPMB prevented microorganisms from adverse effects of substrate inhibition, which facilitated complete removal of phenol from the wastewater. TPPMB retained the advantages of both solvent extraction and biodegradation, and it can be highly promising for the treatment of toxic industrial wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.

Free and Bound Phenolic Compound Content and Antioxidant Activity of Different Cultivated Blue Highland Barley Varieties from the Qinghai-Tibet Plateau.

PubMed

Yang, Xi-Juan; Dang, Bin; Fan, Ming-Tao

2018-04-11

In this study, the polyphenols composition and antioxidant properties of 12 blue highland barley varieties planted on the Qinghai-Tibet Plateau area were measured. The contents of the free, bound and total phenolic acids varied between 166.20-237.60, 170.10-240.75 and 336.29-453.94 mg of gallic acid equivalents per 100 g of dry weight (DW) blue highland barley grains, while the free and bound phenolic acids accounted for 50.09% and 49.91% of the total phenolic acids, respectively. The contents of the free, bound and total flavones varied among 20.61-25.59, 14.91-22.38 and 37.91-47.98 mg of catechin equivalents per 100 g of dry weight (DW) of blue highland barley grains, while the free and bound flavones accounted for 55.90% and 44.10% of the total flavones, respectively. The prominent phenolic compounds in the blue hulless barley grains were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, naringenin, hesperidin, rutin, (+)-catechin and quercetin. Among these, protocatechuic acid, chlorogenic acid and (+)-catechin were the major phenolic compounds in the free phenolics extract. The most abundant bound phenolics were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, benzoic acid, dimethoxybenzoic acid, naringenin, hesperidin, quercetin and rutin. The average contribution of the bound phenolic extract to the DPPH • free radical scavenging capacity was higher than 86%, that of free phenolic extract to the ABTS •+ free radical scavenging capacity was higher than 79%, and that of free phenolic (53%) to the FRAP antioxidant activity was equivalent to that of the bound phenol extract (47%). In addition, the planting environment exerts a very important influence on the polyphenol composition, content and antioxidant activity of blue highland barley. The correlation analysis showed that 2,4-hydroxybenzoic acid and protocatechuic acid were the main contributors to the DPPH • and ABTS •+ free radical scavenging capacity in the free phenolic extract, while chlorogenic acid, vanillic acid, ferulic acid and quercetin were the main contributors to the free radical scavenging capacity in the bound phenol extract. The study results show that the blue highland barley grains have rich phenolic compounds and high antioxidant activity, as well as significant varietal differences. The free and bound phenolic extracts in the blue hulless barley grains have an equivalent proportion in the total phenol, and co-exist in two forms. They can be used as a potential valuable source of natural antioxidants, and can aid in enhancing the development and daily consumption of foods relating to blue highland barley.

Phenol intoxication in a child.

PubMed

Unlü, R Erkin; Alagöz, M Sahin; Uysal, A Caĝri; Orbay, Hakan; Kilinç, Hidir; Tekin, Fatih; Sensöz, Omer; Erk, Gülcan

2004-11-01

Phenol preparations are used in dermatology and plastic surgery for the treatment of acne and during chemical face peeling. At this institution, phenol peeling is used in addition to mechanical dermabrasion for the elimination of subclinical premalignant lesions of patients having xeroderma pigmentosum. As the phenol peel is performed, most surgeons concentrate on skin results, ignoring systemic complications. Local histological changes and systemic toxicity have been seen during applications. Cardiac arrhythmias and even sudden death have been reported. The high incidence of cardiac arrhythmias after topical application of phenol preparations is demonstrated. The case of an 11-year-old boy with a diagnosis of xeroderma pigmentosum who underwent mechanical dermabrasion and chemical peeling with phenol and then developed severe cardiac arrhythmias is reported. A serious systemic toxic effect on cardiac rhythm from cutaneously applied phenol occurred in this case.

Extensive characterisation of bioactive phenolic constituents from globe artichoke (Cynara scolymus L.) by HPLC-DAD-ESI-QTOF-MS.

PubMed

Abu-Reidah, Ibrahim M; Arráez-Román, David; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto

2013-12-01

The aim of this work was to characterise the phenolic compounds in artichoke (hearts) by using HPLC coupled to DAD-ESI-QTOF-MS, which proved useful in characterising 61 phenolic and other polar compounds. Notably, of the 61 compounds characterised, 34 new phenolic compounds with their isomers have been tentatively characterised in artichoke for the first time, namely: 3 hydroxybenzoic acids, 17 hydroxycinnamic acids, 4 lignans, 7 flavones, 2 flavonols, and 1 phenol derivative. Moreover, a total of 28 isomers of previously described phenolics have also been detected. The data compiled from the qualitative polyphenol characterisation indicate that the artichoke extract analysed (Blanca de Tudela variety) could be regarded as a bioactive functional food and also as a promising source of antioxidant phenolic compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Enzyme release of phenolics from muscadine grape (Vitis rotundifolia Michx.) skins and seeds.

PubMed

Xu, Changmou; Yagiz, Yavuz; Borejsza-Wysocki, Wlodzimierz; Lu, Jiang; Gu, Liwei; Ramírez-Rodrigues, Milena M; Marshall, Maurice R

2014-08-15

Enzyme degradation of plant cell wall polysaccharides can potentially enhance the release of bioactive phenolics. The aim of this study was to evaluate various combinations of solvent and enzyme, enzyme type (cellulase, pectinase, ß-glucosidase), and hydrolysis time (1, 4, 8, 24 h) on the release of muscadine grape skin and seed phenolics, and their antioxidant activities. Results showed that pre-treated muscadine skins and seeds with enzymes decreased total phenolic yield compared with solvent (50% ethanol) alone. Enzyme release of phenolics from skins of different muscadine varieties was significantly different while release from seeds was similar. Enzyme hydrolysis was found to shorten extraction time. Most importantly, enzyme hydrolysis modified the galloylated form of polyphenols to low molecular weight phenolics, releasing phenolic acids (especially gallic acid), and enhancing antioxidant activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biochemical changes in phenols, flavonoids, tannins, vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties

PubMed Central

Afify, Abd El-Moneim MR; El-Beltagi, Hossam S; El-Salam, Samiha M Abd; Omran, Azza A

2012-01-01

Objective To investigate the changes in total phenols, flavonoids, tannins, vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties. Methods The changes in total phenols, total flavonoids, tannins, phenolic acids compounds, flavonoid components, vitamin E, β-carotene and antioxidant activity during soaking of sorghum grains were determined. Results Total phenols, total flavonoids, tannins, vitamin E, β-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70, 45.91 to 54.69, 1.39 to 21.79 mg/100 g, 1.74 to 5.25, 0.54 to 1.19 mg/kg and 21.72% to 27.69% and 25.29% to 31.97%, respectively. The above measured compounds were significantly decreased after soaking. p-Hydroxybenzoic acid, vanillic acid, syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety. While ferulic acid, p-coumaric acid, gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6. On the other hand, protocatechuic acid represents the major phenolic acids in Giza-15. Regarding flavonoids components, Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin, hypersoid, quercetin and christen. Finally, Giza-15 was the highest variety in catechin. Phenolic acids, flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions Sorghum varieties have moderate quantities from total phenols, total flavonoids, tannins, phenolic acids compounds, flavonoid components, vitamin E, β-carotene and antioxidant activity which decreased after soaking. PMID:23569898

Biochemical changes in phenols, flavonoids, tannins, vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.

PubMed

Afify, Abd El-Moneim M R; El-Beltagi, Hossam S; El-Salam, Samiha M Abd; Omran, Azza A

2012-03-01

To investigate the changes in total phenols, flavonoids, tannins, vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties. The changes in total phenols, total flavonoids, tannins, phenolic acids compounds, flavonoid components, vitamin E, β-carotene and antioxidant activity during soaking of sorghum grains were determined. Total phenols, total flavonoids, tannins, vitamin E, β-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70, 45.91 to 54.69, 1.39 to 21.79 mg/100 g, 1.74 to 5.25, 0.54 to 1.19 mg/kg and 21.72% to 27.69% and 25.29% to 31.97%, respectively. The above measured compounds were significantly decreased after soaking. p-Hydroxybenzoic acid, vanillic acid, syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety. While ferulic acid, p-coumaric acid, gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6. On the other hand, protocatechuic acid represents the major phenolic acids in Giza-15. Regarding flavonoids components, Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin, hypersoid, quercetin and christen. Finally, Giza-15 was the highest variety in catechin. Phenolic acids, flavonoid compounds and antioxidant activities were decreased after soaking. Sorghum varieties have moderate quantities from total phenols, total flavonoids, tannins, phenolic acids compounds, flavonoid components, vitamin E, β-carotene and antioxidant activity which decreased after soaking.

Formation of brominated phenolic contaminants from natural manganese oxides-catalyzed oxidation of phenol in the presence of Br(.).

PubMed

Lin, Kunde; Song, Lianghui; Zhou, Shiyang; Chen, Da; Gan, Jay

2016-07-01

Brominated phenolic compounds (BPCs) are a class of persistent and potentially toxic compounds ubiquitously present in the aquatic environment. However, the origin of BPCs is not clearly understood. In this study, we investigated the formation of BPCs from natural manganese oxides (MnOx)-catalyzed oxidation of phenol in the presence of Br(-). Experiments at ambient temperature clearly demonstrated that BPCs were readily produced via the oxidation of phenol by MnOx in the presence of Br(-). In the reaction of MnOx sand with 0.213 μmol/L phenol and 0.34 mmol/L Br(-) for 10 min, more than 60% of phenol and 56% of Br(-) were consumed to form BPCs. The yield of BPCs increased with increasing concentrations of phenol and Br(-). Overall, a total of 14 BPCs including simple bromophenols (4-bromophenol, 2,4-dibromophenol, and 2,4,6-tribromophenol), hydroxylated polybrominated diphenyl ethers (OH-PBDEs), and hydroxylated polybrominated biphenyls (OH-PBBs) were identified. The production of BPCs increased with increasing concentrations of Br(-) or phenol. It was deduced that Br(-) was first oxidized to form active bromine, leading to the subsequent bromination of phenol to form bromophenols. The further oxidation of bromophenols by MnOx resulted in the formation of OH-PBDEs and OH-PBBs. In view of the ubiquity of phenol, Br(-), and MnOx in the environment, MnOx-mediated oxidation may play a role on the natural production of BPCs. Copyright © 2016 Elsevier Ltd. All rights reserved.

UV radiation is the primary factor driving the variation in leaf phenolics across Chinese grasslands

PubMed Central

Chen, Litong; Niu, Kechang; Wu, Yi; Geng, Yan; Mi, Zhaorong; Flynn, Dan FB; He, Jin-Sheng

2013-01-01

Due to the role leaf phenolics in defending against ultraviolet B (UVB) under previously controlled conditions, we hypothesize that ultraviolet radiation (UVR) could be a primary factor driving the variation in leaf phenolics in plants over a large geographic scale. We measured leaf total phenolics, ultraviolet-absorbing compounds (UVAC), and corresponding leaf N, P, and specific leaf area (SLA) in 151 common species. These species were from 84 sites across the Tibetan Plateau and Inner Mongolian grasslands of China with contrasting UVR (354 vs. 161 mW/cm2 on average). Overall, leaf phenolics and UVAC were all significantly higher on the Tibetan Plateau than in the Inner Mongolian grasslands, independent of phylogenetic relationships between species. Regression analyses showed that the variation in leaf phenolics was strongly affected by climatic factors, particularly UVR, and soil attributes across all sites. Structural equation modeling (SEM) identified the primary role of UVR in determining leaf phenolic concentrations, after accounting for colinearities with altitude, climatic, and edaphic factors. In addition, phenolics correlated positively with UVAC and SLA, and negatively with leaf N and N: P. These relationships were steeper in the lower-elevation Inner Mongolian than on the Tibetan Plateau grasslands. Our data support that the variation in leaf phenolics is controlled mainly by UV radiation, implying high leaf phenolics facilitates the adaptation of plants to strong irradiation via its UV-screening and/or antioxidation functions, particularly on the Tibetan Plateau. Importantly, our results also suggest that leaf phenolics may influence on vegetation attributes and indirectly affect ecosystem processes by covarying with leaf functional traits. PMID:24363898

Phenolic compounds participating in mulberry juice sediment formation during storage.

PubMed

Zou, Bo; Xu, Yu-Juan; Wu, Ji-Jun; Yu, Yuan-Shan; Xiao, Geng-Sheng

The stability of clarified juice is of great importance in the beverage industry and to consumers. Phenolic compounds are considered to be one of the main factors responsible for sediment formation. The aim of this study is to investigate the changes in the phenolic content in clarified mulberry juice during storage. Hence, separation, identification, quantification, and analysis of the changes in the contents of phenolic compounds, both free and bound forms, in the supernatant and sediments of mulberry juice, were carried out using high performance liquid chromatographic system, equipped with a photo-diode array detector (HPLC-PDA) and HPLC coupled with quadrupole-time of flight mass spectrometric (HPLC-QTOF-MS/MS) techniques. There was an increase in the amount of sediment formed over the period of study. Total phenolic content of supernatant, as well as free phenolic content in the extracts of the precipitate decreased, whereas the bound phenolic content in the sediment increased. Quantitative estimation of individual phenolic compounds indicated high degradation of free anthocyanins in the supernatant and sediment from 938.60 to 2.30 mg/L and 235.60 to 1.74 mg/g, respectively. A decrease in flavonoids in the supernatant was also observed, whereas the contents of bound forms of gallic acid, protocatechuic acid, caffeic acid, and rutin in the sediment increased. Anthocyanins were the most abundant form of phenolics in the sediment, and accounted for 67.2% of total phenolics after 8 weeks of storage. These results revealed that phenolic compounds, particularly anthocyanins, were involved in the formation of sediments in mulberry juice during storage.

Genetic evidence for direct sensing of phenolic compounds by the VirA protein of Agrobacterium tumefaciens.

PubMed Central

Lee, Y W; Jin, S; Sim, W S; Nester, E W

1995-01-01

The virulence (vir) genes of Agrobacterium tumefaciens are induced by low-molecular-weight phenolic compounds and monosaccharides through a two-component regulatory system consisting of the VirA and VirG proteins. However, it is not clear how the phenolic compounds are sensed by the VirA/VirG system. We tested the vir-inducing abilities of 15 different phenolic compounds using four wild-type strains of A. tumefaciens--KU12, C58, A6, and Bo542. We analyzed the relationship between structures of the phenolic compounds and levels of vir gene expression in these strains. In strain KU12, vir genes were not induced by phenolic compounds containing 4'-hydroxy, 3'-methoxy, and 5'-methoxy groups, such as acetosyringone, which strongly induced vir genes of the other three strains. On the other hand, vir genes of strain KU12 were induced by phenolic compounds containing only a 4'-hydroxy group, such as 4-hydroxyacetophenone, which did not induce vir genes of the other three strains. The vir genes of strains KU12, A6, and Bo542 were all induced by phenolic compounds containing 4'-hydroxy and 3'-methoxy groups, such as acetovanillone. By transferring different Ti plasmids into isogenic chromosomal backgrounds, we showed that the phenolic-sensing determinant is associated with Ti plasmid. Subcloning of Ti plasmid indicates that the virA locus determines which phenolic compounds can function as vir gene inducers. These results suggest that the VirA protein directly senses the phenolic compounds for vir gene activation. PMID:8618878

40 CFR 721.7220 - Polymer of substituted phenol, formaldehyde, epichlorohydrin, and disubstituted benzene.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of substituted phenol... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.7220 Polymer of substituted phenol... subject to reporting. (1) The chemical substance identified generically as polymer of substituted phenol...

40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Mixed alkyl phenolic novolak resin... Specific Chemical Substances § 721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical... as mixed alkyl phenolic novolak resin (PMN P-98-718) is subject to reporting under this section for...

40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Mixed alkyl phenolic novolak resin... Specific Chemical Substances § 721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical... as mixed alkyl phenolic novolak resin (PMN P-98-718) is subject to reporting under this section for...

40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Mixed alkyl phenolic novolak resin... Specific Chemical Substances § 721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical... as mixed alkyl phenolic novolak resin (PMN P-98-718) is subject to reporting under this section for...

40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Mixed alkyl phenolic novolak resin... Specific Chemical Substances § 721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical... as mixed alkyl phenolic novolak resin (PMN P-98-718) is subject to reporting under this section for...

40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Mixed alkyl phenolic novolak resin... Specific Chemical Substances § 721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical... as mixed alkyl phenolic novolak resin (PMN P-98-718) is subject to reporting under this section for...

Changes in phenolic compounds and their antioxidant capacities in jujube (Ziziphus jujuba Miller) during three edible maturity stages

USDA-ARS?s Scientific Manuscript database

This study investigated the changes in total phenolic content (TPC), total flavonoid content (TFC), individual phenolic compound content, DPPH radical scavenging activity and antioxidant capacity measured by FRAP assay of four phenolic fractions (free, esterified, glycosided and insoluble-bound) fro...

Reaction of formaldehyde with phenols: a computational chemistry study.

Treesearch

Tohru Mitsunaga; Anthony H. Conner; Charles G. Hill

2001-01-01

Phenolic resins are important adhesives used by the forest products industry. The phenolic compounds in these resins are derived primarily from petrochemical sources. Alternate sources of phenolic compounds include tannins, lignins, biomass pyrolysis products, and coal gasification products. Because of variations in their chemical structures, the reactivities of these...

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for the...

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for the...

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for the...

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for the...

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for the...

Alkylation of phenol by alcohols in the presence of aluminum phenolate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koshchii, V.A.; Kozlikovskii, Ya.B.; Matyusha, A.A.

1988-12-20

The reaction of phenol with alcohols in the presence of aluminum phenolate leads to a mixture of 2- and 4-alkylphenols, of which the former predominate in the case of benzyl, tert-butyl, and cyclohexyl alcohols, and the latter in the case of dimethylphenyl- and diphenylmethylcarbinols. Only triphenyl(4-hydroxyphenyl)-methane is formed during the alkylation of phenol by triphenylcarbinol. In individual experiments the formation of small amounts of alkyl phenyl ethers and 2,6-dialkylphenols was observed.

The roles of plant phenolics in defence and communication during Agrobacterium and Rhizobium infection.

PubMed

Bhattacharya, Amita; Sood, Priyanka; Citovsky, Vitaly

2010-09-01

Phenolics are aromatic benzene ring compounds with one or more hydroxyl groups produced by plants mainly for protection against stress. The functions of phenolic compounds in plant physiology and interactions with biotic and abiotic environments are difficult to overestimate. Phenolics play important roles in plant development, particularly in lignin and pigment biosynthesis. They also provide structural integrity and scaffolding support to plants. Importantly, phenolic phytoalexins, secreted by wounded or otherwise perturbed plants, repel or kill many microorganisms, and some pathogens can counteract or nullify these defences or even subvert them to their own advantage. In this review, we discuss the roles of phenolics in the interactions of plants with Agrobacterium and Rhizobium.

Carbonyl-Phenol Adducts: An Alternative Sink for Reactive and Potentially Toxic Lipid Oxidation Products.

PubMed

Zamora, Rosario; Hidalgo, Francisco J

2018-02-14

Different from the well-characterized function of phenolics as antioxidants, their function as lipid-derived carbonyl scavengers is mostly unknown. However, phenolics react with lipid-derived carbonyls as a function of the nucleophilicity of their reactive groups and the electronic effects and steric hindrances present in the reactive carbonyls. Furthermore, the reaction produces a wide variety of carbonyl-phenol adducts, some of which are stable and have been isolated and characterized but others polymerize spontaneously. This perspective updates present knowledge about the lipid-derived carbonyl trapping ability of phenolics, its competition with carbonyl-amine reactions produced in foods, and the presence of carbonyl-phenol adducts in food products.

Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

DOEpatents

Skotheim, Terje A.; Okamoto, Yoshiyuki; Lee, Hung S.

1989-01-01

The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10.sup.-4 to 10.sup.-7 S cm.sup.-1 at room temperature.

Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

DOEpatents

Skotheim, T.A.; Okamoto, Yoshiyuki; Lee, H.S.

1989-11-21

The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10[sup [minus]4] to 10[sup [minus]7] S cm[sup [minus]1] at room temperature.

Mechanical, Optical, and Barrier Properties of Soy Protein Film As Affected by Phenolic Acid Addition.

PubMed

Insaward, Anchana; Duangmal, Kiattisak; Mahawanich, Thanachan

2015-11-04

This study aimed to explore the effect of phenolic acid addition on properties of soy protein film. Ferulic (FE), caffeic (CA), and gallic (GA) acids as well as their oxidized products were used in this study. Phenolic acid addition was found to have a significant effect (p ≤ 0.05) on the mechanical properties of the film. GA-containing films exhibited the highest tensile strength and elongation at break, followed by those with added CA and FE, respectively. Oxidized phenolic acids were shown to produce a film with higher tensile strength and elongation at break than their unoxidized counterparts. Phenolic acid addition also affected film color and transparency. As compared to the control, phenolic-containing film samples demonstrated reduced water vapor permeability and water solubility and increased contact angle, especially at high concentrations of oxidized phenolic acid addition.

Cultivation of activated sludge using sea mud as seed to treat industrial phenolic wastewater with high salinity.

PubMed

Tan, Songwen; Cui, Chunzhi; Hou, Yang; Chen, Xuncai; Xu, Aiqin; Li, Weiguo; You, Hong

2017-01-30

A technique is proposed to treat saline hazardous wastewater by using marine activated sludge, cultivated with sea mud as seed. Since the developed marine activated sludge had phenol-tolerant microorganisms (MAS-1, MAS-2 and MAS-3) which originated from the ocean, it was envisaged that these bacteria could survive and breakdown phenol in saline environments. In this work, typical phenol-tolerant microorganisms were isolated from the marine activated sludge and identified. After a hierarchical acclimation process, the marine activated sludge was used to treat the industrial phenolic wastewater with high salinity. The marine activated sludge was able to break down phenol and other organic components effectively and efficiently in treating the wastewater with salinity of 5.7% w/v. The results showed a high removal of phenol (99%), COD (80%) and NH 3 -N (68%). Copyright © 2016 Elsevier Ltd. All rights reserved.

HPLC-UV-ESI-MS analysis of phenolic compounds and antioxidant properties of Hypericum undulatum shoot cultures and wild-growing plants.

PubMed

Rainha, Nuno; Koci, Kamila; Coelho, Ana Varela; Lima, Elisabete; Baptista, José; Fernandes-Ferreira, Manuel

2013-02-01

LC-UV and LC-MS analysis were used to study the phenolic composition of water extracts of Hypericum undulatum (HU) shoot cultures and wild-growing (WG) plants. Total phenolic content (TPC), determined using the Folin-Ciocalteu assay, and the antioxidant activity measured by two complementary methods were also performed for each sample. Mass spectrometry revealed several phenolics acids with quinic acid moieties, flavonols, mostly quercetin, luteolin and apigenin glycosides, flavan-3-ols (catechin and epicatechin) and the xanthonoid mangiferin. Differences in phenolic composition profile and TPC were found between the samples. The major phenolic in HU culture-growing (CG) samples is chlorogenic acid, followed by epicatechin, quercitrin and isoquercitrin. The WG plants presents hyperoside as the main phenolic, followed by isoquercitrin, chlorogenic acid and quercetin. The TPC and antioxidant activity were higher in samples from WG plants. Copyright © 2012 Elsevier Ltd. All rights reserved.

Phenol degradation catalyzed by a peroxidase mimic constructed through the grafting of heme onto metal-organic frameworks.

PubMed

Jiang, Wei; Yang, Jiebing; Wang, Xinghuo; Han, Haobo; Yang, Yan; Tang, Jun; Li, Quanshun

2018-01-01

The aim of this work was to construct a peroxidase mimic for achieving the phenol degradation through Fenton reaction. The enzyme mimic was synthesized through the conjugation of heme with the amino group of 2-amino-1,4-benzene dicarboxylate in UiO-66-NH 2 (ZrMOF), namely Heme-ZrMOF. Compared to free heme, the composite Heme-ZrMOF exhibited an obviously enhanced ability for phenol degradation with up to 97.3% of phenol removal after 2h. Meanwhile, it could achieve the easy separation of catalyst from the system and the elimination of iron residues in the process of phenol degradation. Finally, the catalyst Heme-ZrMOF was observed to possess good recyclability in the phenol degradation with still 76.2% of phenol removal after 4 cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

Catalytic ozonation of aqueous phenol over metal-loaded HZSM-5.

PubMed

Amin, Nor Aishah Saidina; Akhtar, Javaid; Rai, H K

2011-01-01

The performances of HZSM-5 and transition metal-loaded HZSM-5 (Mn, Cu, Fe, Ti) catalysts during catalytic ozonation of phenol have been investigated. It was observed the performance order for removal of phenol and COD was Mn/HZSM-5 > Fe/HZSM-5 > Cu/HZSM-5 > Ti/HZSM-5 > HZSM-5. The presence of metals on HZSM-5 enhanced the phenol removal capability of HZSM-5. Mn loading on HZSM-5 was optimized due to its high phenol removal capability amongst metal-loaded HZSM-5 catalysts. Experimental results suggested that low amount of Mn loading on HZSM-5 was sufficient for HZSM-5 to act as catalyst and adsorbent. A maximum of 95.8 wt% phenols and 70.2 wt% COD were removed over 2 wt% Mn/HZSM-5 in 120 min. It was supposed that transition metals mainly acted as ozone decomposers due to their multiple oxidation states that enhanced the ozonation of phenol.

Toxic effects of phenol on grey mullet, Mugil auratus Risso

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krajnovic-Ozretic, M.; Ozretic, B.

1988-01-01

Phenolic compounds are frequently found as contaminants in surface waters, including marine coastal waters. Phenols are generally classified as nonspecific metabolic inhibitors, and the main toxic effects are manifested on the nervous system due to the dissolution of lipids, whereas in the circulatory system phenols act as hemolysing agents of the erythrocytes. Data about sublethal effects of phenol, particularly to marine organisms are rather scarce. In several fresh water fish species exposed to phenol, the number of erythrocytes and the amount of serum proteins were decreased while lesion of gill filaments with edema and blood infiltration with degenerative changes inmore » liver were also observed. These investigations concerned the identification of some physiological and biochemical changes in mullet blood as a consequence of exposure to phenol and some observations about the behavior and gross pathology of poisoned fish were also made.« less

Phenolic Compounds Analysis of Root, Stalk, and Leaves of Nettle

PubMed Central

Otles, Semih; Yalcin, Buket

2012-01-01

Types of nettles (Urtica dioica) were collected from different regions to analyze phenolic compounds in this research. Nettles are specially grown in the coastal part. According to this kind of properties, nettle samples were collected from coastal part of (Mediterranean, Aegean, Black sea, and Marmara) Turkey. Phenolic profile, total phenol compounds, and antioxidant activities of nettle samples were analyzed. Nettles were separated to the part of root, stalk, and leaves. Then, these parts of nettle were analyzed to understand the difference of phenolic compounds and amount of them. Nettle (root, stalk and leaves) samples were analyzed by using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) to qualitative and quantitative determination of the phenolic compounds. Total phenolic components were measured by using Folin-Ciocalteu method. The antioxidant activity was measured by using DPPH (2,2-diphenyl-1-picrylhydrazyl) which is generally used for herbal samples and based on single electron transfer (SET). PMID:22593694

Phenolic compounds analysis of root, stalk, and leaves of nettle.

PubMed

Otles, Semih; Yalcin, Buket

2012-01-01

Types of nettles (Urtica dioica) were collected from different regions to analyze phenolic compounds in this research. Nettles are specially grown in the coastal part. According to this kind of properties, nettle samples were collected from coastal part of (Mediterranean, Aegean, Black sea, and Marmara) Turkey. Phenolic profile, total phenol compounds, and antioxidant activities of nettle samples were analyzed. Nettles were separated to the part of root, stalk, and leaves. Then, these parts of nettle were analyzed to understand the difference of phenolic compounds and amount of them. Nettle (root, stalk and leaves) samples were analyzed by using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) to qualitative and quantitative determination of the phenolic compounds. Total phenolic components were measured by using Folin-Ciocalteu method. The antioxidant activity was measured by using DPPH (2,2-diphenyl-1-picrylhydrazyl) which is generally used for herbal samples and based on single electron transfer (SET).

Phenolic acids potentiate colistin-mediated killing of Acinetobacter baumannii by inducing redox imbalance.

PubMed

Ajiboye, Taofeek O; Skiebe, Evelyn; Wilharm, Gottfried

2018-05-01

Phenolic acids with catechol groups are good prooxidants because of their low redox potential. In this study, we provided data showing that phenolic acids, caffeic acid, gallic acid and protocatechuic acid, enhanced colistin-mediated bacterial death by inducing redox imbalance. The minimum inhibitory concentrations of these phenolic acids against Acinetobacter baumannii AB5075 were considerably lowered for ΔsodB and ΔkatG mutants. Checkerboard assay shows synergistic interactions between colistin and phenolic acids. The phenolic acids exacerbated colistin-induced oxidative stress in A. baumannii AB5075 through increased superoxide anion generation, NAD + /NADH and ADP/ATP ratio. In parallel, the level of reduced glutathione was significantly lowered. We conclude that phenolic acids potentiate colistin-induced oxidative stress in A. baumannii AB5075 by increasing ROS generation, energy metabolism and electron transport chain activity with a concomitant decrease in glutathione. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Method and device for fabricating dispersion fuel comprising fission product collection spaces

DOEpatents

Shaber, Eric L; Fielding, Randall S

2015-05-05

A method of fabricating a nuclear fuel comprising a fissile material, one or more hollow microballoons, a phenolic resin, and metal matrix. The fissile material, phenolic resin and the one or more hollow microballoons are combined. The combined fissile material, phenolic resin and the hollow microballoons are heated sufficiently to form at least some fissile material carbides creating a nuclear fuel particle. The resulting nuclear fuel particle comprises one or more fission product collection spaces. In a preferred embodiment, the fissile material, phenolic resin and the one or more hollow microballoons are combined by forming the fissile material into microspheres. The fissile material microspheres are then overcoated with the phenolic resin and microballoon. In another preferred embodiment, the fissile material, phenolic resin and the one or more hollow microballoons are combined by overcoating the microballoon with the fissile material, and phenolic resin.

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Reaction product of phenolic... Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and glyceride... substances identified generically as Reaction product of phenolic pentaerythritol tetraesters with fatty acid...

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Reaction product of phenolic... Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and glyceride... substances identified generically as Reaction product of phenolic pentaerythritol tetraesters with fatty acid...

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Reaction product of phenolic... Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and glyceride... substances identified generically as Reaction product of phenolic pentaerythritol tetraesters with fatty acid...

40 CFR 721.10054 - Phenol, polymer with formaldehyde, 3-[(2-aminocyclohexyl)amino]-2-hydroxypropyl ethers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol, polymer with formaldehyde, 3... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10054 Phenol, polymer with... uses subject to reporting. (1) The chemical substance identified generically as a phenol, polymer with...

40 CFR 721.10054 - Phenol, polymer with formaldehyde, 3-[(2-aminocyclohexyl)amino]-2-hydroxypropyl ethers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phenol, polymer with formaldehyde, 3... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10054 Phenol, polymer with... uses subject to reporting. (1) The chemical substance identified generically as a phenol, polymer with...

An integrated high resolution mass spectrometric and informatics approach for the rapid identification of phenolics in plant extract

USDA-ARS?s Scientific Manuscript database

An integrated approach based on high resolution MS analysis (orbitrap), database (db) searching and MS/MS fragmentation prediction for the rapid identification of plant phenols is reported. The approach was firstly validated by using a mixture of phenolic standards (phenolic acids, flavones, flavono...

Carbohydrate modified phenol-formaldehyde resins

Treesearch

Anthony H. Conner; Linda F. Lorenz

1986-01-01

For adhesive self-sufficiency, the wood industry needs new adhesive systems in which all or part of the petroleum-derived phenolic component is replaced by a renewable material without sacrificing high durability or ease of bonding. We tested the bonding of wood veneers, using phenolic resins in which part of the phenol-formaldehyde was replaced with carbohydrates. Our...

Adaptation in Caco-2 human intestinal cell differentiation and phenolic transport with chronic exposure to phenolic-rich blackberry (Rubus sp.) extract

USDA-ARS?s Scientific Manuscript database

As evidence mounts for a health-protective role of dietary phenolics, the importance of understanding factors influencing bioavailability increases. Recent evidence has suggested chronic exposure may impact phenolic absorption and metabolism. To explore alterations occurring from chronic dietary e...

40 CFR 721.10054 - Phenol, polymer with formaldehyde, 3-[(2-aminocyclohexyl)amino]-2-hydroxypropyl ethers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phenol, polymer with formaldehyde, 3... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10054 Phenol, polymer with... uses subject to reporting. (1) The chemical substance identified generically as a phenol, polymer with...

40 CFR 721.10054 - Phenol, polymer with formaldehyde, 3-[(2-aminocyclohexyl)amino]-2-hydroxypropyl ethers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phenol, polymer with formaldehyde, 3... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10054 Phenol, polymer with... uses subject to reporting. (1) The chemical substance identified generically as a phenol, polymer with...

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reaction product of phenolic... Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and glyceride... substances identified generically as Reaction product of phenolic pentaerythritol tetraesters with fatty acid...

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Reaction product of phenolic... Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and glyceride... substances identified generically as Reaction product of phenolic pentaerythritol tetraesters with fatty acid...

40 CFR 721.10190 - Formaldehyde, polymer with aliphatic diamine and phenol, reaction products with 4-methyl-2...

Code of Federal Regulations, 2011 CFR

2011-07-01

... diamine and phenol, reaction products with 4-methyl-2-pentanone (generic). 721.10190 Section 721.10190... Formaldehyde, polymer with aliphatic diamine and phenol, reaction products with 4-methyl-2-pentanone (generic... identified generically as formaldehyde, polymer with aliphatic diamine and phenol, reaction products with 4...

40 CFR 721.10190 - Formaldehyde, polymer with aliphatic diamine and phenol, reaction products with 4-methyl-2...

Code of Federal Regulations, 2010 CFR

2010-07-01

... diamine and phenol, reaction products with 4-methyl-2-pentanone (generic). 721.10190 Section 721.10190... Formaldehyde, polymer with aliphatic diamine and phenol, reaction products with 4-methyl-2-pentanone (generic... identified generically as formaldehyde, polymer with aliphatic diamine and phenol, reaction products with 4...

Phenolics and compartmentalization in the sapwood of broad-leaved trees

Treesearch

Kevin T. Smith

1997-01-01

Tree survival depends on the chemistry of phenolic compounds, a broad class of chemicals characterized by a hydroxylated benzene ring. In trees, phenolics occur frequently as polymers, acids, or glycosylated esters and perform diverse functions. For example, lignin, a phenylpropane heteropolymer, provides structural strength to wood. The induced production of phenols...

Content of different groups of phenolic compounds in microshoots of Juglans regia cultivars and studies on antioxidant activity

USDA-ARS?s Scientific Manuscript database

Phenolic and other compounds were extracted from micropropagated axillary shoots (microshoots) of the walnut (Juglans regia L.) cultivars ‘Chandler’, ‘Howard’, ‘Kerman’, ‘Sunland’, and ‘Z63’. Among cultivars, microshoots showed differences in phenolic compounds, phenolic acids, flavonoids and proant...

Anaerobic biodegradation of phenolic compounds in digested sludge.

PubMed Central

Boyd, S A; Shelton, D R; Berry, D; Tiedje, J M

1983-01-01

We examined the anaerobic degradation of phenol and the ortho, meta, and para isomers of chlorophenol, methoxyphenol, methylphenol (cresol), and nitrophenol in anaerobic sewage sludge diluted to 10% in a mineral salts medium. Of the 12 monosubstituted phenols studied, only p-chlorophenol and o-cresol were not significantly degraded during an 8-week incubation period. The phenol compounds degraded and the time required for complete substrate disappearance (in weeks) were: phenol (2), o-chlorophenol (3), m-chlorophenol (7), o-methoxyphenol (2), m- and p-methoxyphenol (1), m-cresol (7), p-cresol (3), and o-, m-, and p-nitrophenol (1). Complete mineralization of phenol, o-chlorophenol, m-cresol, p-cresol, o-nitrophenol, p-nitrophenol, and o-, m-, and p-methoxyphenol was observed. In general, the presence of Cl and NO2 groups on phenols inhibited methane production. Elimination or transformation of these substituents was accompanied by increased methane production, o-Chlorophenol was metabolized to phenol, which indicated that dechlorination was the initial degradation step. The methoxyphenols were transformed to the corresponding dihydroxybenzene compounds, which were subsequently mineralized. PMID:6614908

A review of phenolic compounds in oil-bearing plants: Distribution, identification and occurrence of phenolic compounds.

PubMed

Alu'datt, Muhammad H; Rababah, Taha; Alhamad, Mohammad N; Al-Mahasneh, Majdi A; Almajwal, Ali; Gammoh, Sana; Ereifej, Khalil; Johargy, Ayman; Alli, Inteaz

2017-03-01

Over the last two decades, separation, identification and measurement of the total and individual content of phenolic compounds has been widely investigated. Recently, the presence of a wide range of phenolic compounds in oil-bearing plants has been shown to contribute to their therapeutic properties, including anti-cancer, anti-viral, anti-oxidant, hypoglycemic, hypo-lipidemic, and anti-inflammatory activities. Phenolics in oil-bearing plants are now recognized as important minor food components due to several organoleptic and health properties, and they are used as food or sources of food ingredients. Variations in the content of phenolics in oil-bearing plants have largely been attributed to several factors, including the cultivation, time of harvest and soil types. A number of authors have suggested that the presence phenolics in extracted proteins, carbohydrates and oils may contribute to objectionable off flavors The objective of this study was to review the distribution, identification and occurrence of free and bound phenolic compounds in oil-bearing plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Adsorption of phenol chemicals by surfactant-modified zeolites].

PubMed

Xie, Jie; Wang, Zhe; Wu, De-Yi; Li, Chun-Jie

2012-12-01

Two kinds of zeolites were prepared from fly ash and modified by surfactant subsequently. Surfactant-modified zeolites were studied for adsorption of phenol chemicals (phenol, p-chlorphenol, bisphenol A). It showed that the adsorption affinity of zeolite to phenol chemicals was significantly improved after surfactant modification. The adsorption isotherms of phenol chemicals were well fitted by the Langmuir isotherm. For the two surfactant-surfactant modified zeolites, the maximum adsorption amounts of phenol, p-chlorphenol, and bisphenol A calculated from the Langmuir equation were 37.7, 52.36, 90.9 mg x g(-1) and 10.7, 22.83, 56.8 mg x g(-1), respectively. When pH values of solutions were higher than the pK(a) values of phenol chemicals, the removal efficiencies were getting higher with the increase of pH values. The octanol/water partition coefficient (K(ow)) was also found to be an important factor affecting adsorption of phenol chemicals by the modified zeolites. Higher K(ow) value, which means the greater hydrophobicity of the chemicals, resulted in a higher removal.

Preparation of Activated Carbon From Polygonum orientale Linn. to Remove the Phenol in Aqueous Solutions

PubMed Central

Feng, Jia; Shi, Shengli; Pei, Liangyu; Lv, Junping; Liu, Qi; Xie, Shulian

2016-01-01

Phenol components are major industry contaminants of aquatic environment. Among all practical methods for removing phenol substances from polluted water, activated carbon absorption is the most effective way. Here, we have produced low-cost activated carbon using Polygonum orientale Linn, a wide spreading species with large biomass. The phenol adsorption ability of this activated carbon was evaluated at different physico-chemical conditions. Average equilibrium time for adsorption was 120 min. The phenol adsorption ability of the P. orientale activated carbon was increased as the pH increases and reached to the max at pH 9.00. By contrast, the ionic strength had little effect on the phenol absorption. The optimum dose for phenol adsorption by the P. orientale activated carbon was 20.00 g/L. The dominant adsorption mechanism of the P. orientale activated carbon was chemisorption as its phenol adsorption kinetics matched with the pseudo-second-order kinetics. In addition, the equilibrium data were fit to the Langmuir model, with the negative standard free energy and the positive enthalpy, suggesting that adsorption was spontaneous and endothermic. PMID:27741305

Phenol and chlorinated phenols exhibit different apoptotic potential in human red blood cells (in vitro study).

PubMed

Michałowicz, Jaromir; Włuka, Anna; Cyrkler, Monika; Maćczak, Aneta; Sicińska, Paulina; Mokra, Katarzyna

2018-05-23

Phenol and chlorinated phenols are widely spread in the environment and human surrounding, which leads to a common environmental and occupational exposure of humans to these substances. The aim of this study was to assess eryptotic changes in human red blood cells treated with phenol, 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP). The erythrocytes were incubated with phenols studied in the concentrations ranging from 1 to 100 μg/mL for 24 h or 48 h. The results of the study revealed that all compounds studied caused phosphatidylserine translocation and increased cytosolic calcium ions level in human erythrocytes. It was also noticed that phenol and chlorophenols caused an increase in caspase-3 and calpain activation, which confirmed that they were capable of inducing suicidal death of erythrocytes. The results also revealed that PCP most strongly altered the parameters studied, while phenol exhibited the weakest eryptotic potential in the incubated cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Preparation of Activated Carbon From Polygonum orientale Linn. to Remove the Phenol in Aqueous Solutions.

PubMed

Feng, Jia; Shi, Shengli; Pei, Liangyu; Lv, Junping; Liu, Qi; Xie, Shulian

2016-01-01

Phenol components are major industry contaminants of aquatic environment. Among all practical methods for removing phenol substances from polluted water, activated carbon absorption is the most effective way. Here, we have produced low-cost activated carbon using Polygonum orientale Linn, a wide spreading species with large biomass. The phenol adsorption ability of this activated carbon was evaluated at different physico-chemical conditions. Average equilibrium time for adsorption was 120 min. The phenol adsorption ability of the P. orientale activated carbon was increased as the pH increases and reached to the max at pH 9.00. By contrast, the ionic strength had little effect on the phenol absorption. The optimum dose for phenol adsorption by the P. orientale activated carbon was 20.00 g/L. The dominant adsorption mechanism of the P. orientale activated carbon was chemisorption as its phenol adsorption kinetics matched with the pseudo-second-order kinetics. In addition, the equilibrium data were fit to the Langmuir model, with the negative standard free energy and the positive enthalpy, suggesting that adsorption was spontaneous and endothermic.

Pilot-scale resin adsorption as a means to recover and fractionate apple polyphenols.

PubMed

Kammerer, Dietmar R; Carle, Reinhold; Stanley, Roger A; Saleh, Zaid S

2010-06-09

The purification and fractionation of phenolic compounds from crude plant extracts using a food-grade acrylic adsorbent were studied at pilot-plant scale. A diluted apple juice concentrate served as a model phenolic solution for column adsorption and desorption trials. Phenolic concentrations were evaluated photometrically using the Folin-Ciocalteu assay and by HPLC-DAD. Recovery rates were significantly affected by increasing phenolic concentrations of the feed solutions applied to the column. In contrast, the flow rate during column loading hardly influenced adsorption efficiency, whereas the temperature and pH value were shown to be crucial parameters determining both total phenolic recovery rates and the adsorption behavior of individual polyphenols. As expected, the eluent composition had the greatest impact on the desorption characteristics of both total and individual phenolic compounds. HPLC analyses revealed significantly different elution profiles of individual polyphenols depending on lipophilicity. This technique allows fractionation of crude plant phenolic extracts, thus providing the opportunity to design the functional properties of the resulting phenolic fractions selectively, and the present study delivers valuable information with regard to the adjustment of individual process parameters.

Fermentation and complex enzyme hydrolysis enhance total phenolics and antioxidant activity of aqueous solution from rice bran pretreated by steaming with α-amylase.

PubMed

Liu, Lei; Zhang, Ruifen; Deng, Yuanyuan; Zhang, Yan; Xiao, Juan; Huang, Fei; Wen, Wei; Zhang, Mingwei

2017-04-15

In this study, rice bran was successively steamed with α-amylase, fermented with lactic acid bacteria, and hydrolyzed with complex enzymes. The changes in phenolic profiles and antioxidant activities of the corresponding aqueous solutions from three stages were investigated. Compared to the first stage, fermentation and complex enzyme hydrolysis significantly increased the total phenolics, total flavonoids, total FRAP and ORAC values by 59.2%, 56.6%, 73.6% and 45.4%, respectively. Twelve individual phenolics present in free or soluble conjugate forms were also analyzed during the processing. Ferulic acid was released in the highest amount among different phenolics followed by protocatechuic acid. Moreover, a major proportion of phenolics existed as soluble conjugates. The results showed that fermentation and complex enzyme hydrolysis enhanced total phenolics and antioxidant activities of aqueous solution from rice bran pretreated by steaming with α-amylase. This research could provide basis for the processing of rice bran beverage rich in phenolics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enzyme-assisted extraction of phenolics from winemaking by-products: Antioxidant potential and inhibition of alpha-glucosidase and lipase activities.

PubMed

de Camargo, Adriano Costa; Regitano-d'Arce, Marisa Aparecida Bismara; Biasoto, Aline Camarão Telles; Shahidi, Fereidoon

2016-12-01

Phenolics in food and agricultural processing by-products exist in the soluble and insoluble-bound forms. The ability of selected enzymes in improving the extraction of insoluble-bound phenolics from the starting material (experiment I) or the residues containing insoluble-bound phenolics (experiment II) were evaluated. Pronase and Viscozyme improved the extraction of insoluble-bound phenolics as evaluated by total phenolic content, antioxidant potential as determined by ABTS and DPPH assays, and hydroxyl radical scavenging capacity, reducing power as well as evaluation of inhibition of alpha-glucosidase and lipase activities. Viscozyme released higher amounts of gallic acid, catechin, and prodelphinidin dimer A compared to Pronase treatment. Furthermore, p-coumaric and caffeic acids, as well as procyanidin dimer B, were extracted with Viscozyme but not with Pronase treatment. Solubility plays an important role in the bioavailability of phenolic compounds, hence this study may assist in better exploitation of phenolics from winemaking by-products as functional food ingredients and/or supplements. Copyright © 2016. Published by Elsevier Ltd.

Fast pyrolysis of palm kernel shells: influence of operation parameters on the bio-oil yield and the yield of phenol and phenolic compounds.

PubMed

Kim, Seon-Jin; Jung, Su-Hwa; Kim, Joo-Sik

2010-12-01

Palm kernel shells were pyrolyzed in a pyrolysis plant equipped with a fluidized-bed reactor and a char-separation system. The influence of reaction temperature, feed size and feed rate on the product spectrum was also investigated. In addition, the effect of reaction temperature on the yields of phenol and phenolic compounds in the bio-oil was examined. The maximum bio-oil yield was 48.7 wt.% of the product at 490 degrees C. The maximum yield of phenol plus phenolic compounds amounted to about 70 area percentage at 475 degrees C. The yield of pyrolytic lignin after its isolation from the bio-oil was approximately 46 wt.% based on the water and ash free oil. The pyrolytic lignin was mainly composed of phenol, phenolic compounds and oligomers of coniferyl, sinapyl and p-coumaryl alcohols. From the result of a GPC analysis, the number average molecular weight and the weight average molecular weight were 325 and 463 g/mol, respectively. 2010 Elsevier Ltd. All rights reserved.

Comparative evaluation of maceration and ultrasonic-assisted extraction of phenolic compounds from fresh olives.

PubMed

Deng, Junlin; Xu, Zhou; Xiang, Chunrong; Liu, Jing; Zhou, Lijun; Li, Tian; Yang, Zeshen; Ding, Chunbang

2017-07-01

Ultrasonic-assisted extraction (UAE) and maceration extraction (ME) were optimized using response surface methodology (RSM) for total phenolic compounds (TPC) from fresh olives. The main phenolic compounds and antioxidant activity of TPC were also investigated. The optimized result for UAE was 22mL/g of liquid-solid ratio, 47°C of extraction temperature and 30min of extraction time, 7.01mg/g of yielding, and for ME was 24mL/g of liquid-solid ratio, 50°C of extraction temperature and 4.7h of extraction time, 5.18mg/g of yielding. The HPLC analysis revealed that the extracts by UAE and ME possessed 14 main phenolic compounds, and UAE exhibited more amounts of all phenols than ME. The most abundant phenolic compounds in olive extracts were hydroxytyrosol, oleuropein and rutin. Both extracts showed excellent antioxidant activity in a dose-dependent manner. Taken together, UAE could effectively increase the yield of phenolic compounds from olives. In addition these phenolic compounds could be used as a potential source of natural antioxidants. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification and Quantification of Avenanthramides and Free and Bound Phenolic Acids in Eight Cultivars of Husked Oat ( Avena sativa L) from Finland.

PubMed

Multari, Salvatore; Pihlava, Juha-Matti; Ollennu-Chuasam, Priscilla; Hietaniemi, Veli; Yang, Baoru; Suomela, Jukka-Pekka

2018-03-21

Finland is the second largest oat producer in Europe. Despite the existing knowledge of phenolics in oat, there is little information on the phenolic composition of oats from Finland. The aim of the study was to investigate the concentrations of free and bound phenolic acids, as well as avenanthramides in eight Finnish cultivars of husked oat ( Avena sativa L.). Seven phenolic acids and one phenolic aldehyde were identified, including, in decreasing order of abundance: p-coumaric, ferulic, cinnamic, syringic, vanillic, 2,4-dihydroxybenzoic, and o-coumaric acids and syringaldehyde. Phenolic acids were mostly found as bound compounds. Significant varietal differences ( p < 0.05) were observed in the cumulative content of phenolic acids, with the lowest level found in cv. 'Viviana' (1202 ± 52.9 mg kg -1 ) and the highest in cv. 'Akseli' (1687 ± 80.2 mg kg -1 ). Avenanthramides (AVNs) 2a, 2p, and 2f were the most abundant. Total AVNs levels ranged from 26.7 ± 1.44 to 185 ± 12.5 mg kg -1 in cv. 'Avetron' and 'Viviana', respectively.

Hydrogen Bonding-Mediated Microphase Separation during the Formation of Mesoporous Novolac-Type Phenolic Resin Templated by the Triblock Copolymer, PEO-b-PPO-b-PEO

PubMed Central

Chu, Wei-Cheng; Chiang, Shih-Fan; Li, Jheng-Guang; Kuo, Shiao-Wei

2013-01-01

After blending the triblock copolymer, poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-b-PPO-b-PEO) with novolac-type phenolic resin, Fourier transform infrared spectroscopy revealed that the ether groups of the PEO block were stronger hydrogen bond acceptors for the OH groups of phenolic resin than were the ether groups of the PPO block. Thermal curing with hexamethylenetetramine as the curing agent resulted in the triblock copolymer being incorporated into the phenolic resin, forming a nanostructure through a mechanism involving reaction-induced microphase separation. Mild pyrolysis conditions led to the removal of the PEO-b-PPO-b-PEO triblock copolymer and formation of mesoporous phenolic resin. This approach provided a variety of composition-dependent nanostructures, including disordered wormlike, body-centered-cubic spherical and disorder micelles. The regular mesoporous novolac-type phenolic resin was formed only at a phenolic content of 40–60 wt %, the result of an intriguing balance of hydrogen bonding interactions among the phenolic resin and the PEO and PPO segments of the triblock copolymer. PMID:28788378

Phenolic compounds extracted by acidic aqueous ethanol from berries and leaves of different berry plants.

PubMed

Tian, Ye; Liimatainen, Jaana; Alanne, Aino-Liisa; Lindstedt, Anni; Liu, Pengzhan; Sinkkonen, Jari; Kallio, Heikki; Yang, Baoru

2017-04-01

Phenolic compounds of berries and leaves of thirteen various plant species were extracted with aqueous ethanol and analyzed with UPLC-DAD-ESI-MS, HPLC-DAD, and NMR. The total content of phenolics was consistently higher in leaves than in berries (25-7856 vs. 28-711mg/100g fresh weight). Sea buckthorn leaves were richest in phenolic compounds (7856mg/100g f.w.) with ellagitannins as the dominant compound class. Sea buckthorn berries contained mostly isorhamnetin glycosides, whereas quercetin glycosides were typically abundant in most samples investigated. Anthocyanins formed the dominating group of phenolics in most dark-colored berries but phenolic acid derivatives were equally abundant in saskatoon and chokeberry berries. Caffeoylquinic acids constituted 80% of the total phenolic content (1664mg/100g f.w.) in bilberry leaves. B-type procyanidins and caffeoylquinic acids were the major phenolic compounds in hawthorn and rowanberry, respectively. Use of leaves of some species with prunasin, tyramine and β-p-arbutin, may be limited in food applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Standardization of the carbon-phenolic materials and processes. Vol. 2: Test methods and specifications

NASA Technical Reports Server (NTRS)

Hall, William B.

1988-01-01

Carbon-phenolic composite materials are used in the ablation process in the nozzles of the Space Shuttle Main Engine. The nozzle is lined with carbon cloth-phenolic resin composites. The extreme heat and erosion of the burning propellant are controlled by the carbon-phenolic composite by means of ablation, a heat and mass transfer process in which a large amount of heat is dissipated by sacrificailly removing material from a surface. Phenolic materials ablate with the initial formation of a char. The depth of the char is a function of the heat conduction coefficient of the composite. The char layer is a poor conductor so it protects the underlying phenolic composite from the high heat of the burning propellant. The nozzle component ablative liners (carbon cloth-phenolic resin composites) are tape wrapped, hydroclave and/or autoclave cured, machined and assembled. The tape consists of prepreg broadcloth. The materials flow sheet for the nozzle ablative liners is given. The prepreg is a three component system: phenolic resin, carbon cloth, and carbon filler. This is Volume 2 of the report, Test Methods and Specifications.

Influence of different processing and storage conditions on in vitro bioaccessibility of polyphenols in black carrot jams and marmalades.

PubMed

Kamiloglu, Senem; Pasli, Ayca Ayfer; Ozcelik, Beraat; Van Camp, John; Capanoglu, Esra

2015-11-01

Black carrot is indicated to play an important role in nutrition, as it comprises a variety of health-promoting components, including polyphenols. The objective of the present study was to monitor the stability of total phenolics, antioxidant capacity and phenolic acids in black carrot jams and marmalades after processing, storage and in vitro gastrointestinal digestion. Total phenolic content and antioxidant capacity were determined using spectrophotometric methods, whereas phenolic acids were identified using HPLC-PDA. Jam and marmalade processing significantly decreased total phenolics (89.2-90.5%), antioxidant capacity (83.3-91.3%) and phenolic acids (49.5-96.7%) (p < 0.05). After 20 weeks of storage, the percent decrease in total phenolics in samples stored at 25 °C (26.4-48.0%) was slightly higher than the samples stored at 4 °C (21.0-42.5%). In addition, jam and marmalade processing led to increases in the percent recovery of bioaccessible total phenolics (7.2-12.6%) and phenolic acids (4.7-31.5%), as well as antioxidant capacity (1.4-8.1%). In conclusion, current study highlighted black carrot jams and marmalades as good sources of polyphenols, with high bioaccessibility levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Food processing strategies to enhance phenolic compounds bioaccessibility and bioavailability in plant-based foods.

PubMed

Ribas-Agustí, Albert; Martín-Belloso, Olga; Soliva-Fortuny, Robert; Elez-Martínez, Pedro

2017-06-13

Phenolic compounds are important constituents of plant-based foods, as their presence is related to protective effects on health. To exert their biological activity, phenolic compounds must be released from the matrix during digestion in an absorbable form (bioaccessible) and finally absorbed and transferred to the bloodstream (bioavailable). Chemical structure and matrix interactions are some food-related factors that hamper phenolic compounds bioaccessibility and bioavailability, and that can be counteracted by food processing. It has been shown that food processing can induce chemical or physical modifications in food that enhance phenolic compounds bioaccessibility and bioavailability. These changes include: (i) chemical modifications into more bioaccessible and bioavailable forms; (ii) cleavage of covalent or hydrogen bonds or hydrophobic forces that attach phenolic compounds to matrix macromolecules; (iii) damaging microstructural barriers such as cell walls that impede the release from the matrix; and (iv) create microstructures that protect phenolic compounds until they are absorbed. Indeed, food processing can produce degradation of phenolic compounds, however, it is possible to counteract it by modulating the operating conditions in favor of increased bioaccessibility and bioavailability. This review compiles the current knowledge on the effects of processing on phenolic compounds bioaccessibility or bioavailability, while suggesting new guidelines in the search of optimal processing conditions as a step forward towards the design of healthier foods.

Adaptation in Caco-2 Human Intestinal Cell Differentiation and Phenolic Transport with Chronic Exposure to Blackberry (Rubus sp.) Extract.

PubMed

Redan, Benjamin W; Albaugh, George P; Charron, Craig S; Novotny, Janet A; Ferruzzi, Mario G

2017-04-05

As evidence mounts for a health-protective role of dietary phenolics, the importance of understanding factors influencing bioavailability increases. Recent evidence has suggested chronic exposure to phenolics may impact their absorption and metabolism. To explore alterations occurring from chronic dietary exposure to phenolics, Caco-2 cell monolayers were differentiated on Transwell inserts with 0-10 μM blackberry (Rubus sp.) total phenolics extracts rich in anthocyanins, flavonols, and phenolic acids. Following differentiation, apical to basolateral transport of phenolics was assessed from an acute treatment of 100 μM blackberry phenolics from 0 to 4 h. Additionally, differences in gene expression of transport and phase II metabolizing systems including ABC transporters, organic anion transporters (OATs), and uridine 5'-diphospho (UDP) glucuronosyltransferases (UGTs) were probed. After 4 h, 1 μM pretreated monolayers showed a significant (P < 0.05) decrease in the percentage of cumulative transport including less epicatechin (42.1 ± 0.53), kaempferol glucoside (23.5 ± 0.29), and dicaffeoylquinic acid (31.9 ± 0.20) compared to control. Finally, significant (P < 0.05) alterations in mRNA expression of key phase II metabolizing enzymes and transport proteins were observed with treatment. Therefore, adaptation to blackberry extract exposure may impact intestinal transport and metabolism of phenolics.

Phenolic Molding Compounds

NASA Astrophysics Data System (ADS)

Koizumi, Koji; Charles, Ted; de Keyser, Hendrik

Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.

Mutagenicity testing in the Salmonella typhimurium assay of phenolic compounds and phenolic fractions obtained from smokehouse smoke condensates.

PubMed

Pool, B L; Lin, P Z

1982-08-01

Smokehouse smoke, which is used for flavouring meat products, was investigated for its mutagenic activity in the Salmonella typhimurium assay. We were chiefly concerned with the fractions free of polycyclic aromatic hydrocarbons but containing phenol compounds, which are responsible for the preservative and aromatizing properties of the smoke. The most abundantly occurring phenol compounds (phenol, cresols, 2,4-dimethylphenol, brenzcatechine, syringol, eugenol, vanilline and guaiacol) gave negative results when they were tested for mutagenicity at five concentrations up to 5000 micrograms/plate, with and without S-9 mix, using five strains of S. typhimurium. Even when phenol was further investigated in a variety of test conditions, no induction of his+ revertants was observed. When smokehouse smoke was condensed and fractionated the majority of the various phenolic fractions also gave negative results when tested at five concentrations using five strains of S. typhimurium. However there was a slight increase in the number of revertants in a few cases. The presence in the phenolic fractions of very small amounts of mutagenic impurities, the nature of which needs further investigation, cannot be excluded. These results support the further development of non-hazardous smoke-aroma preparations, based on the phenolic components of smokehouse smoke.

Low molecular weight phenolics of grape juice and winemaking byproducts: antioxidant activities and inhibition of oxidation of human low-density lipoprotein cholesterol and DNA strand breakage.

PubMed

de Camargo, Adriano Costa; Regitano-d'Arce, Marisa Aparecida Bismara; Biasoto, Aline Camarão Telles; Shahidi, Fereidoon

2014-12-17

Bioactive compounds belonging to phenolic acids, flavonoids, and proanthocyanidins of grape juice and winemaking byproducts were identified and quantified by HPLC-DAD-ESI-MS(n). The concentration of phenolic compounds in different grape cultivars was in the order Tempranillo > Cora > Syrah > Isabel. The insoluble-bound fraction was most prominent, contributing 63 and 79% to the total for Isabel and Tempranillo, respectively. Juice-processing byproducts had a higher content of free than esterified phenolics, but the opposite was noted for winemaking byproducts. Insoluble-bound phenolics were up to 15 and 10 times more effective as antioxidants than those of free and esterified fractions, respectively, as evaluated by the DPPH, ABTS, and H2O2 scavenging activities and reducing power determinations. In general, insoluble-bound phenolics (100 ppm) were more effective in inhibiting copper-induced human LDL-cholesterol oxidation than free and esterified phenolics, exhibiting equal or higher efficacy than catechin. Phenolic extracts from all fractions inhibited peroxyl radical-induced DNA strand breakage. These findings shed further light for future studies and industrial application of grape byproducts, which may focus not only on the soluble phenolics but also on the insoluble-bound fraction.

Phenols removal using ozonation-adsorption with granular activated carbon (GAC) in rotating packed bed reactor

NASA Astrophysics Data System (ADS)

Karamah, E. F.; Leonita, S.; Bismo, S.

2018-01-01

Synthetic wastewater containing phenols was treated using combination method of ozonation-adsorption with GAC (Granular Activated Carbon) in a packed bed rotating reactor. Ozone reacts quickly with phenol and activated carbon increases the oxidation process by producing hydroxyl radicals. Performance parameters evaluated are phenol removal percentage, the quantity of hydroxyl radical formed, changes in pH and ozone utilization, dissolved ozone concentration and ozone concentration in off gas. The performance of the combination method was compared with single ozonation and single adsorption. The influence of GAC dose and initial pH of phenols were evaluated in ozonation-adsorption method. The results show that ozonation-adsorption method generates more OH radicals than a single ozonation. Quantity of OH radical formation increases with increasing pH and quantity of the GAC. The combination method prove better performance in removing phenols. At the same operation condition, ozonation-adsorption method is capable of removing of 78.62% phenols as compared with single ozonation (53.15%) and single adsorption (36.67%). The increasing percentage of phenol removal in ozonation-adsorption method is proportional to the addition of GAC dose, solution pH, and packed bed rotator speed. Maximum percentage of phenol removal is obtained under alkaline conditions (pH 10) and 125 g of GAC

Phytochemical Contents and Antioxidant and Antiproliferative Activities of Selected Black and White Sesame Seeds

PubMed Central

Abbasi, Arshad Mehmood; Zheng, Bisheng

2016-01-01

Sesame (Sesamum indicum L.) seeds are popular nutritional food but with limited knowledge about their antioxidant and antiproliferative activities of various varieties. Phytochemical profiles and antioxidant and antiproliferative activities of six varieties of sesame (Sesamum indicum L.) seeds were studied. Fenheizhi3 (black) cultivar exhibited the maximum contents of total phenolics and lignans and values of total oxygen radical absorbance capacity (ORAC) and antiproliferative activity (EC50) against HepG2 cells. Bound ORAC values showed strong associations with bound phenolics contents (r = 0.976, p < 0.01); in bound phenolic extracts, EC50 values showed strong negative associations with phenolic contents (r = −0.869, p < 0.05) and ORAC values (r = −0.918, p < 0.01). Moreover, the contents of free phenolics were higher than that of the bound phenolics, and the three black sesame seeds generally depicted higher total phenolics compared to the three white varieties. The antioxidant (ORAC values) and antiproliferation activities of six sesame seeds were both associated with contents of bound phenolics (r > 0.8, p < 0.05). Interestingly, nonlignan components in bound phenolics contributed to the antioxidant and antiproliferative activities. This study suggested that Fenheizhi3 variety is superior to the other five varieties as antioxidant supplements. PMID:27597975

Evaluation of SRB phenolic TPS material made by an alternate vendor

NASA Technical Reports Server (NTRS)

Karu, Z. S.

1982-01-01

Tests conducted to evaluate the adequacy of solid rocket booster (SRB) phenolic thermal protection system (TPS) material supplied by an alternate vendor chosen by United Space Boosters, Inc. (USBI), to replace the current phenolic TPS sections used thus far on the first four Shuttle flights. The phenolic TPS is applied mainly to the attach and kick rings of the solid rocket booster (SRB). Full-scale sectional models of both the attach and kick ring structure were made up with 0.0265 in. thick stainless steel thin skin covers with thermocouples on them to determine the heating rates. Such models were made up for both the forward and rear faces of the kick ring which has a different configuration on each side. The thin skins were replaced with the alternate phenolic TPS sections cut from flight hardware configuration phenolic parts as supplied by the new vendor. Two tests were performed for each configuration of the attach and kick rings and the samples were exposed to the flow for a duration that gave a heat load equivalent to that obtained in the series of runs made for the current line of phenolic TPS. The samples performed very well with no loss of any phenolic layers. The post-test samples looked better than those used to verify the current phenolic TPS.

In vitro digestibility, free and bound phenolic profiles and antioxidant activity of thermally treated Eragrostis tef L.

PubMed

Koubová, Eva; Mrázková, Martina; Sumczynski, Daniela; Orsavová, Jana

2018-06-01

Total phenolic content, phenolic profile and antioxidant activity were determined in free and bound phenolic fractions of thermally treated brown and white teff grains. Phenolic content in raw brown and white teff (1540 and 992 mg gallic acid equivalent kg -1 ) as well as antioxidant activity (6.3 and 5.5 mmol trolox equivalent kg -1 ) were higher in free phenolic fractions. The most significant decrease in total phenolics was observed after application of the sous-vide method (35% for brown teff and 11% for white teff). Main free phenolics of heat-treated teff were ferulic, protocatechuic, p-coumaric and ellagic acids, rutin and epigallocatechin. Main bound phenolics were ferulic, gallic, sinapic and ellagic acids, catechin and epigallocatechin. The detrimental effect on free and bound quercetin and bound cinnamic acid concentrations was also examined during heat treatment. Thermally treated brown teff showed a high level of in vitro organic matter digestibility if water cooking and rice cooker (both 99.5%) and sous-vide (96.5%) methods were applied. The sous-vide method may be recommended as the most suitable hydrothermal treatment for grains of teff when compared with water cooking and rice cooker methods. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Long-Term Uptake of Phenol-Water Vapor Follows Similar Sigmoid Kinetics on Prehydrated Organic Matter- and Clay-Rich Soil Sorbents.

PubMed

Borisover, Mikhail; Bukhanovsky, Nadezhda; Lado, Marcos

2017-09-19

Typical experimental time frames allowed for equilibrating water-organic vapors with soil sorbents might lead to overlooking slow chemical reactions finally controlling a thermodynamically stable state. In this work, long-term gravimetric examination of kinetics covering about 4000 h was performed for phenol-water vapor interacting with four materials pre-equilibrated at three levels of air relative humidity (RHs 52, 73, and 92%). The four contrasting sorbents included an organic matter (OM)-rich peat soil, an OM-poor clay soil, a hydrophilic Aldrich humic acid salt, and water-insoluble leonardite. Monitoring phenol-water vapor interactions with the prehydrated sorbents, as compared with the sorbent samples in phenol-free atmosphere at the same RH, showed, for the first time, a sigmoid kinetics of phenol-induced mass uptake typical for second-order autocatalytic reactions. The apparent rate constants were similar for all the sorbents, RHs and phenol activities studied. A significant part of sorbed phenol resisted extraction, which was attributed to its abiotic oxidative coupling. Phenol uptake by peat and clay soils was also associated with a significant enhancement of water retention. The delayed development of the sigmoidal kinetics in phenol-water uptake demonstrates that long-run abiotic interactions of water-organic vapor with soil may be overlooked, based on short-term examination.

[Effects on phenol removal in the process of enhanced coagulation by manganese dioxide formed in situ].

PubMed

Zhang, Li-Zhu; Chen, Xiao-Dong; Ma, Jun; Yu, Min; Li, Xin

2011-10-01

Phenol was selected as a model compound. Factors, such as Ca2+, tannic acid, dose of kaolinite, dose of manganese dioxide formed in situ and pH, were invested on phenol removal in the process of enhanced coagulation by manganese dioxide formed in situ. Results showed that the addition of Ca2+ is beneficial for phenol removal. In the range of Ca2+ varied from 0 to 1.0 mmol x L(-1), the efficiency of phenol removal was enhanced more than 10%. Tannic acid can enhance phenol removal significantly when they are coexisted in water. As tannic acid was added to 10 mg x L(-1), phenol removal can be increased about 30% and 50% in the process of coagulation by AlCl3 and enhanced coagulation by manganese dioxide formed in situ, respectively. The dose of coagulant can be reduced in the process of enhanced coagulation with the addition of manganese dioxide formed in situ. The point of 1 mg x L(-1) manganese dioxide formed in situ linked with 30 mg x L(-1) AlCl3 can have the same phenol removal efficiency as the addition of 50 mg x L(-1) AlCl3. In the range of pH varied from 5 to 9, phenol can be removed with the high efficiency in the process of enhanced coagulation by manganese dioxide formed in situ. While under the strong acid condition and strong basic condition, phenol has lower removal efficiency.

Total Phenolic, Phenolic Acid, Anthocyanin, Flavan-3-ol, and Flavonol Profiles and Antioxidant Properties of Pinto and Black Beans ( Phaseolus vulgaris L.) as Affected by Thermal Processing.

PubMed

Xu, Baojun; Chang, Sam K C

2009-06-10

The effects of boiling and steaming processes at atmospheric and high pressures on the phenolic components and antioxidant properties of pinto and black beans were investigated. In comparison to the original raw beans, all processing methods caused significant (p < 0.05) decreases in total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), monomeric anthocyanin content (MAC), DPPH free-radical scavenging activity (DPPH), ferric-reducing antioxidant power (FRAP), and oxygen radical absorbing capacity (ORAC) values in both pinto and black beans. Steaming processing resulted in a greater retention of TPC, DPPH, FRAP, and ORAC values than the boiling processes in both pinto and black beans. To further investigate how thermal processing affected phenolic compositions and to elucidate the contribution of individual phenolic compounds to antioxidant properties, phenolic acids, anthocyanins, flavan-3-ols, and flavonols were quantitatively analyzed by high-performance liquid chromatography (HPLC). All thermal processing significantly (p < 0.05) affected individual phenolic acids, anthocyanins, flavan-3-ols, and flavonols, significantly (p < 0.05) reduced total phenolic acid contents in both pinto and black beans and total flavonol contents in pinto beans, and dramatically reduced anthocyanin contents in black beans. Phenolic acids and flavonols may play important roles on the overall antioxidant activities of pinto beans, while anthocyanins, flavan-3-ols, and flavonols may play important roles on the overall antioxidant activities of black beans.

Rapid establishment of phenol- and quinoline-degrading consortia driven by the scoured cake layer in an anaerobic baffled ceramic membrane bioreactor.

PubMed

Wang, Wei; Wang, Shun; Ren, Xuesong; Hu, Zhenhu; Yuan, Shoujun

2017-11-01

Although toxic and refractory organics, such as phenol and quinoline, are decomposed by anaerobic bacteria, the establishment of specific degrading consortia is a relatively slow process. An anaerobic membrane bioreactor allows for complete biomass retention that can aid the establishment of phenol- and quinoline-degrading consortia. In this study, the anaerobic digestion of phenol (500 mg L -1 ) and quinoline (50 mg L -1 ) was investigated using an anaerobic baffled ceramic membrane bioreactor (ABCMBR). The results showed that, within 30 days, 99% of phenol, 98% of quinoline and 88% of chemical oxygen demand (COD) were removed. The substrate utilisation rates of the cake layer for phenol and quinoline, and specific methanogenic activity of the cake layer, were 7.58 mg phenol g -1  mixed liquor volatile suspended solids (MLVSS) day -1 , 8.23 mg quinoline g -1  MLVSS day -1 and 0.55 g COD CH4  g -1  MLVSS day -1 , respectively. The contribution of the cake layer to the removals of phenol and quinoline was extremely underestimated because the uncounted scoured cake layer was disregarded. Syntrophus was the key population for phenol and quinoline degradation, and it was more abundant in the cake layer than in the bulk sludge. The highly active scattered cake layer sped up the establishment of phenol- and quinoline-degrading consortia in the ABCMBR.

Rapid degradation of phenol by ultrasound-dispersed nano-metallic particles (NMPs) in the presence of hydrogen peroxide: A possible mechanism for phenol degradation in water.

PubMed

Singh, Jiwan; Yang, Jae-Kyu; Chang, Yoon-Young

2016-06-15

The present study was carried out to investigate the degradation of phenol by ultrasonically dispersed nano-metallic particles (NMPs) in an aqueous solution of phenol. Leaching liquor from automobile shredder residue (ASR) was used to obtain the NMPs. The prepared NMPs were analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and by X-ray diffraction (XRD). The SEM images show that the diameters of the NMPs were less than 50 nm. An SEM-EDX elemental analysis reveals that Fe was the most commonly found element (weight %) in the NMPs. The FTIR and XRD peaks indicate the presence of metals oxides on the surfaces of the NMPs. The results of the XPS analysis indicate that various elements (e.g., C, O, Zn, Cu, Mn, Fe) are present on the surfaces of the NMPs. The effects of the NMP dose, the initial solution pH, and of different concentrations of phenol and H2O2 on the phenol degradation characteristics were evaluated. The results of this study demonstrate that phenol degradation can be improved by increasing the amount of NMPs, whereas it is reduced with an increase in the phenol concentration. The degradation of phenol by ultrasonically dispersed NMPs followed the pseudo-first-order kinetics. The probable mechanism of phenol degradation by ultrasonically dispersed NMPs was the oxidation of phenol caused by the hydroxyl radicals produced during the reaction between H2O2 and the NMPs during the ultrasonication process. Copyright © 2016 Elsevier Ltd. All rights reserved.

Elevated circulating LDL phenol levels in men who consumed virgin rather than refined olive oil are associated with less oxidation of plasma LDL.

PubMed

de la Torre-Carbot, Karina; Chávez-Servín, Jorge L; Jaúregui, Olga; Castellote, Ana I; Lamuela-Raventós, Rosa M; Nurmi, Tarja; Poulsen, Henrik E; Gaddi, Antonio V; Kaikkonen, Jari; Zunft, Hans-Franz; Kiesewetter, Holger; Fitó, Montserrat; Covas, María-Isabel; López-Sabater, M Carmen

2010-03-01

In human LDL, the bioactivity of olive oil phenols is determined by the in vivo disposition of the biological metabolites of these compounds. Here, we examined how the ingestion of 2 similar olive oils affected the content of the metabolic forms of olive oil phenols in LDL in men. The oils differed in phenol concentrations as follows: high (629 mg/L) for virgin olive oil (VOO) and null (0 mg/L) for refined olive oil (ROO). The study population consisted of a subsample from the EUROLIVE study and a randomized controlled, crossover design was used. Intervention periods lasted 3 wk and were preceded by a 2-wk washout period. The levels of LDL hydroxytyrosol monosulfate and homovanillic acid sulfate, but not of tyrosol sulfate, increased after VOO ingestion (P < 0.05), whereas the concentrations of circulating oxidation markers, including oxidized LDL (oxLDL), conjugated dienes, and hydroxy fatty acids, decreased (P < 0.05). The levels of LDL phenols and oxidation markers were not affected by ROO consumption. The relative increase in the 3 LDL phenols was greater when men consumed VOO than when they consumed ROO (P < 0.05), as was the relative decrease in plasma oxLDL (P = 0.001) and hydroxy fatty acids (P < 0.001). Plasma oxLDL concentrations were negatively correlated with the LDL phenol levels (r = -0.296; P = 0.013). Phenols in LDL were not associated with other oxidation markers. In summary, the phenol concentration of olive oil modulates the phenolic metabolite content in LDL after sustained, daily consumption. The inverse relationship of these metabolites with the degree of LDL oxidation supports the in vivo antioxidant role of olive oil phenolics compounds.

Efficiency of phenol biodegradation by planktonic Pseudomonas pseudoalcaligenes (a constructed wetland isolate) vs. root and gravel biofilm.

PubMed

Kurzbaum, Eyal; Kirzhner, Felix; Sela, Shlomo; Zimmels, Yoram; Armon, Robert

2010-09-01

In the last two decades, constructed wetland systems gained increasing interest in wastewater treatment and as such have been intensively studied around the world. While most of the studies showed excellent removal of various pollutants, the exact contribution, in kinetic terms, of its particular components (such as: root, gravel and water) combined with bacteria is almost nonexistent. In the present study, a phenol degrader bacterium identified as Pseudomonas pseudoalcaligenes was isolated from a constructed wetland, and used in an experimental set-up containing: plants and gravel. Phenol removal rate by planktonic and biofilm bacteria (on sterile Zea mays roots and gravel surfaces) was studied. Specific phenol removal rates revealed significant advantage of planktonic cells (1.04 × 10(-9) mg phenol/CFU/h) compared to root and gravel biofilms: 4.59 × 10(-11)-2.04 × 10(-10) and 8.04 × 10(-11)-4.39 × 10(-10) (mg phenol/CFU/h), respectively. In batch cultures, phenol biodegradation kinetic parameters were determined by biomass growth rates and phenol removal as a function of time. Based on Haldane equation, kinetic constants such as μ(max) = 1.15/h, K(s) = 35.4 mg/L and K(i) = 198.6 mg/L fit well phenol removal by P. pseudoalcaligenes. Although P. pseudoalcaligenes planktonic cells showed the highest phenol removal rate, in constructed wetland systems and especially in those with sub-surface flow, it is expected that surface associated microorganisms (biofilms) will provide a much higher contribution in phenol and other organics removal, due to greater bacterial biomass. Factors affecting the performance of planktonic vs. biofilm bacteria in sub-surface flow constructed wetlands are further discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

Absorption, Metabolic Stability, and Pharmacokinetics of Ginger Phytochemicals.

PubMed

Mukkavilli, Rao; Yang, Chunhua; Singh Tanwar, Reenu; Ghareeb, Ahmed; Luthra, Latika; Aneja, Ritu

2017-03-30

We have previously demonstrated promising anticancer efficacy of orally-fed whole ginger extract (GE) in preclinical prostate models emphasizing the importance of preservation of the natural "milieu". Essentially, GE primarily includes active ginger phenolics viz., 6-gingerol (6G), 8-gingerol (8G), 10-gingerol (10G), and 6-shogaol (6S). However, the druglikeness properties of active GE phenolics like solubility, stability, and metabolic characteristics are poorly understood. Herein, we determined the physicochemical and biochemical properties of GE phenolics by conducting in vitro assays and mouse pharmacokinetic studies with and without co-administration of ketoconazole (KTZ). GE phenolics showed low to moderate solubility in various pH buffers but were stable in simulated gastric and intestinal fluids, indicating their suitability for oral administration. All GE phenolics were metabolically unstable and showed high intrinsic clearance in mouse, rat, dog, and human liver microsomes. Upon oral administration of 250 mg/kg GE, sub-therapeutic concentrations of GE phenolics were observed. Treatment of plasma samples with β-glucuronidase (βgd) increased the exposure of all GE phenolics by 10 to 700-fold. Co-administration of KTZ with GE increased the exposure of free GE phenolics by 3 to 60-fold. Interestingly, when the same samples were treated with βgd, the exposure of GE phenolics increased by 11 to 60-fold, suggesting inhibition of phase I metabolism by KTZ but little effect on glucuronide conjugation. Correlating the in vitro and in vivo results, it is reasonable to conclude that phase II metabolism seems to be the predominant clearance pathway for GE phenolics. We present evidence that the first-pass metabolism, particularly glucuronide conjugation of GE phenolics, underlies low systemic exposure.

Fourier transform infrared spectroscopy as a metabolite fingerprinting tool for monitoring the phenotypic changes in complex bacterial communities capable of degrading phenol.

PubMed

Wharfe, Emma S; Jarvis, Roger M; Winder, Catherine L; Whiteley, Andrew S; Goodacre, Royston

2010-12-01

The coking process produces great volumes of wastewater contaminated with pollutants such as cyanides, sulfides and phenolics. Chemical and physical remediation of this wastewater removes the majority of these pollutants; however, these processes do not remove phenol and thiocyanate. The removal of these compounds has been effected during bioremediation with activated sludge containing a complex microbial community. In this investigation we acquired activated sludge from an industrial bioreactor capable of degrading phenol. The sludge was incubated in our laboratory and monitored for its ability to degrade phenol over a 48 h period. Multiple samples were taken across the time-course and analysed by Fourier transform infrared (FT-IR) spectroscopy. FT-IR was used as a whole-organism fingerprinting approach to monitor biochemical changes in the bacterial cells during the degradation of phenol. We also investigated the ability of the activated sludge to degrade phenol following extended periods (2-131 days) of storage in the absence of phenol. A reduction was observed in the ability of the microbial community to degrade phenol and this was accompanied by a detectable biochemical change in the FT-IR fingerprint related to cellular phenotype of the microbial community. In the absence of phenol a decrease in thiocyanate vibrations was observed, reflecting the ability of these communities to degrade this substrate. Actively degrading communities showed an additional new band in their FT-IR spectra that could be attributed to phenol degradation products from the ortho- and meta-cleavage of the aromatic ring. This study demonstrates that FT-IR spectroscopy when combined with chemometric analysis is a very powerful high throughput screening approach for assessing the metabolic capability of complex microbial communities. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

Reinvestigation of the role of humic acid in the oxidation of phenols by permanganate.

PubMed

Sun, Bo; Zhang, Jing; Du, Juanshan; Qiao, Junlian; Guan, Xiaohong

2013-12-17

Humic acid (HA) affects the oxidation of phenolic compounds by permanganate, but the role of HA in the oxidation of phenols by permanganate is far from clear. The mechanisms by which HA influences the oxidation of phenols by permanganate at pH 5.0-9.0 were systematically examined in this study. The presence of HA enhanced the oxidation of phenolic compounds by permanganate at pH ≤7.0, with greater enhancement at lower pH values. The presence of HA facilitated the in situ formation of MnO2, implying the importance of reductive moieties of HA in this reaction. This was supported by the finding that HA preoxidized by ozone showed enhancements in the oxidation of phenols by permanganate at pH 5.0-6.0 smaller than those seen with pristine HA. The good correlation between HA-induced improvement in the oxidation rates of phenols by permanganate and those by preformed colloidal MnO2 at pH 5.0 confirmed that contribution of MnO2 formed in situ for the oxidation of phenols under this condition. The differences in the influence of Na2S2O3 and HA on the oxidation of phenol by permanganate revealed the fact that the continuous generation of fresh MnO2 and stabilization of the MnO2 formed in situ by HA were crucial for the HA-induced enhancement of the oxidation of phenols by permanganate at pH ≤7.0. The consumption of permanganate by HA and the poor oxidation ability of in situ-generated MnO2 under alkaline conditions resulted in the slightly negative effect of HA on the degradation rates of phenols by permanganate at pH >7.0.

Secondary Organic Aerosol Produced from Aqueous Reactions of Phenols in Fog Drops and Deliquesced Particles

NASA Astrophysics Data System (ADS)

Smith, J.; Anastasio, C.

2014-12-01

The formation and evolution of secondary organic aerosol (SOA) in atmospheric condensed phases (i.e., aqueous SOA) can proceed rapidly, but relatively little is known of the important aqueous SOA precursors or their reaction pathways. In our work we are studying the aqueous SOA formed from reactions of phenols (phenol, guaiacol, and syringol), benzene-diols (catechol, resorcinol, and hydroquinone), and phenolic carbonyls (e.g., vanillin and syringaldehyde). These species are potentially important aqueous SOA precursors because they are released in large quantities from biomass burning, have high Henry's Law constants (KH = 103 -109 M-1 atm-1) and are rapidly oxidized. To evaluate the importance of aqueous reactions of phenols as a source of SOA, we first quantified the kinetics and SOA mass yields for 11 phenols reacting via direct photodegradation, hydroxyl radical (•OH), and with an excited organic triplet state (3C*). In the second step, which is the focus of this work, we use these laboratory results in a simple model of fog chemistry using conditions during a previously reported heavy biomass burning event in Bakersfield, CA. Our calculations indicate that under aqueous aerosol conditions (i.e., a liquid water content of 100 μg m-3) the rate of aqueous SOA production (RSOA(aq)) from phenols is similar to the rate in the gas phase. In contrast, under fog/cloud conditions the aqueous RSOA from phenols is 10 times higher than the rate in the gas phase. In both of these cases aqueous RSOA is dominated by the oxidation of phenols by 3C*, followed by direct photodegradation of phenolic carbonyls, and then •OH oxidation. Our results suggest that aqueous oxidation of phenols is a significant source of SOA during fog events and also during times when deliquesced aerosols are present.

Isolation of phenolic compounds from hop extracts using polyvinylpolypyrrolidone: characterization by high-performance liquid chromatography-diode array detection-electrospray tandem mass spectrometry.

PubMed

Magalhães, Paulo J; Vieira, Joana S; Gonçalves, Luís M; Pacheco, João G; Guido, Luís F; Barros, Aquiles A

2010-05-07

The aim of the present work was the development of a suitable methodology for the separation and determination of phenolic compounds in the hop plant. The developed methodology was based on the sample purification by adsorption of phenolic compounds from the matrix to polyvinylpolypyrrolidone (PVPP) and subsequent desorption of the adsorbed polyphenols with acetone/water (70:30, v/v). At last, the extract was analyzed by HPLC-DAD and HPLC-ESI-MS/MS. The first phase of this work consisted of the study of the adsorption behavior of several classes of phenolic compounds (e.g. phenolic acids, flavonols, and flavanols) by PVPP in model solutions. It has been observed that the process of adsorption of the different phenolic compounds to PVPP (at low concentrations) is differentiated, depending on the structure of the compound (number of OH groups, aromatic rings, and stereochemistry hindrance). For example, within the phenolic acids class (benzoic, p-hydroxybenzoic, protocatechuic and gallic acids) the PVPP adsorption increases with the number of OH groups of the phenolic compound. On the other hand, the derivatization of OH groups (methylation and glycosylation) resulted in a greatly diminished binding. The use of PVPP revealed to be very efficient for adsorption of several phenolic compounds such as catechin, epicatechin, xanthohumol and quercetin, since high adsorption and recovery values were obtained. The methodology was further applied for the extraction and isolation of phenolic compounds from hops. With this methodology, it was possible to obtain high adsorption values (>or=80%) and recovery yield values (>or=70%) for the most important phenolic compounds from hops such as xanthohumol, catechin, epicatechin, quercetin and kaempferol glycosides, and in addition it allows the identification of about 30 phenolic compounds by HPLC-DAD and HPLC-ESI-MS/MS. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Emissions of fine particulate nitrated phenols from the burning of five common types of biomass.

PubMed

Wang, Xinfeng; Gu, Rongrong; Wang, Liwei; Xu, Wenxue; Zhang, Yating; Chen, Bing; Li, Weijun; Xue, Likun; Chen, Jianmin; Wang, Wenxing

2017-11-01

Nitrated phenols are among the major constituents of brown carbon and affect both climates and ecosystems. However, emissions from biomass burning, which comprise one of the most important primary sources of atmospheric nitrated phenols, are not well understood. In this study, the concentrations and proportions of 10 nitrated phenols, including nitrophenols, nitrocatechols, nitrosalicylic acids, and dinitrophenol, in fine particles from biomass smoke were determined under three different burning conditions (flaming, weakly flaming, and smoldering) with five common types of biomass (leaves, branches, corncob, corn stalk, and wheat straw). The total abundances of fine nitrated phenols produced by biomass burning ranged from 2.0 to 99.5 μg m -3 . The compositions of nitrated phenols varied with biomass types and burning conditions. 4-nitrocatechol and methyl nitrocatechols were generally most abundant, accounting for up to 88-95% of total nitrated phenols in flaming burning condition. The emission ratios of nitrated phenols to PM 2.5 increased with the completeness of combustion and ranged from 7 to 45 ppmm and from 239 to 1081 ppmm for smoldering and flaming burning, respectively. The ratios of fine nitrated phenols to organic matter in biomass burning aerosols were comparable to or lower than those in ambient aerosols affected by biomass burning, indicating that secondary formation contributed to ambient levels of fine nitrated phenols. The emission factors of fine nitrated phenols from flaming biomass burning were estimated based on the measured mass fractions and the PM 2.5 emission factors from literature and were approximately 0.75-11.1 mg kg -1 . According to calculations based on corn and wheat production in 31 Chinese provinces in 2013, the total estimated emission of fine nitrated phenols from the burning of corncobs, corn stalks, and wheat straw was 670 t. This work highlights the apparent emission of methyl nitrocatechols from biomass burning and provides basic data for modeling studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Variations of total phenol, carotenoid, in vitro antioxidant contents, and phenolic profiles of the pulp of five commercial varieties of mango

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in the peel, seeds, and leaves of mango, yet less is known about the phenolic ...

40 CFR 721.3807 - Formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Formaldehyde, polymer with phenol and... Significant New Uses for Specific Chemical Substances § 721.3807 Formaldehyde, polymer with phenol and 1,2,3... chemical substance identified as formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated (PMN...

40 CFR 721.3807 - Formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Formaldehyde, polymer with phenol and... Significant New Uses for Specific Chemical Substances § 721.3807 Formaldehyde, polymer with phenol and 1,2,3... chemical substance identified as formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated (PMN...

40 CFR 721.3807 - Formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Formaldehyde, polymer with phenol and... Significant New Uses for Specific Chemical Substances § 721.3807 Formaldehyde, polymer with phenol and 1,2,3... chemical substance identified as formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated (PMN...

40 CFR 721.3807 - Formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Formaldehyde, polymer with phenol and... Significant New Uses for Specific Chemical Substances § 721.3807 Formaldehyde, polymer with phenol and 1,2,3... chemical substance identified as formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated (PMN...

40 CFR 721.3807 - Formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Formaldehyde, polymer with phenol and... Significant New Uses for Specific Chemical Substances § 721.3807 Formaldehyde, polymer with phenol and 1,2,3... chemical substance identified as formaldehyde, polymer with phenol and 1,2,3-propanetriol, methylated (PMN...

Synthesis and cure kinetics of liquefied wood/phenol/formaldehyde resins

Treesearch

Hui Pan; Todd F. Shupe; Chung-Yun Hse

2008-01-01

Wood liquefaction was conducted at a 2/1 phenol/wood ratio in two different reactors: (1) an atmospheric three-necked flask reactor and (2) a sealed Parr reactor. The liquefied wood mixture (liquefied wood, unreacted phenol, and wood residue) was further condensed with formaldehyde under acidic conditions to synthesize two novolac-type liquefied wood/phenol/...

Preliminary study on chicken feather protein-based wood adhesives

Treesearch

Zehui Jiang; Daochun Qin; Chung-Yun Hse; Monlin Kuo; Zhaohui Luo; Ge Wang; Yan Yu

2008-01-01

The objective of this preliminary study was to partially replace phenol in the synthesis of phenol-formaldehyde resin with feather protein. Feather protein–based resins, which contained one part feather protein and two parts phenol, were formulated under the conditions of two feather protein hydrolysis methods (with and without presence of phenol during...

Investigating Hydrogen Bonding in Phenol Using Infrared Spectroscopy and Computational Chemistry

ERIC Educational Resources Information Center

Fedor, Anna M.; Toda, Megan J.

2014-01-01

The hydrogen bonding of phenol can be used as an introductory model for biological systems because of its structural similarities to tyrosine, a para-substituted phenol that is an amino acid essential to the synthesis of proteins. Phenol is able to form hydrogen bonds readily in solution, which makes it a suitable model for biological…

Olive Tree (Olea europeae L.) Leaves: Importance and Advances in the Analysis of Phenolic Compounds

PubMed Central

Abaza, Leila; Taamalli, Amani; Nsir, Houda; Zarrouk, Mokhtar

2015-01-01

Phenolic compounds are becoming increasingly popular because of their potential role in contributing to human health. Experimental evidence obtained from human and animal studies demonstrate that phenolic compounds from Olea europaea leaves have biological activities which may be important in the reduction in risk and severity of certain chronic diseases. Therefore, an accurate profiling of phenolics is a crucial issue. In this article, we present a review work on current treatment and analytical methods used to extract, identify, and/or quantify phenolic compounds in olive leaves. PMID:26783953

RESPONSE OF PHENOLIC METABOLISM INDUCED BY ALUMINIUM TOXICITY IN FAGOPYRUM ESCULENTUM MOENCH. PLANTS.

PubMed

Smirnov, O E; Kosyan, A M; Kosyk, O I; Taran, N Yu

2015-01-01

Buckwheat genus (Fagopyrum Mill.) is one of the aluminium tolerant taxonomic units of plants. The aim of the study was an evaluation of the aluminium (50 μM effect on phenolic accumulation in various parts of buckwheat plants (Fagopyrum esculentum Moench). Detection of increasing of total phenolic content, changes in flavonoid and anthocyanin content and phenylalanine ammonia-lyase activity (PAL) were revealed over a period of 10 days of exposure to aluminium. The most significant effects of aluminium treatment on phenolic compounds accumulation were total phenolic content increasing (by 27.2%) and PAL activity rising by 2.5 times observed in leaves tissues. Received data could be helpful to understand the aluminium tolerance principles and relationships of phenolic compounds to aluminium phytotoxicity.

Total phenolics and total flavonoids in selected Indian medicinal plants.

PubMed

Sulaiman, C T; Balachandran, Indira

2012-05-01

Plant phenolics and flavonoids have a powerful biological activity, which outlines the necessity of their determination. The phenolics and flavonoids content of 20 medicinal plants were determined in the present investigation. The phenolic content was determined by using Folin-Ciocalteu assay. The total flavonoids were measured spectrophotometrically by using the aluminium chloride colorimetric assay. The results showed that the family Mimosaceae is the richest source of phenolics, (Acacia nilotica: 80.63 mg gallic acid equivalents, Acacia catechu 78.12 mg gallic acid equivalents, Albizia lebbeck 66.23 mg gallic acid equivalents). The highest total flavonoid content was revealed in Senna tora which belongs to the family Caesalpiniaceae. The present study also shows the ratio of flavonoids to the phenolics in each sample for their specificity.

A Comprehensive Study on Chlorella pyrenoidosa for Phenol Degradation and its Potential Applicability as Biodiesel Feedstock and Animal Feed.

PubMed

Das, Bhaskar; Mandal, Tapas K; Patra, Sanjukta

2015-07-01

The present work evaluates the phenol degradative performance of microalgae Chlorella pyrenoidosa. High-performance liquid chromatography (HPLC) analysis showed that C. pyrenoidosa degrades phenol completely up to 200 mg/l. It could also metabolize phenol in refinery wastewater. Biokinetic parameters obtained are the following: growth kinetics, μ max (media) > μ max (refinery wastewater), K s(media) < K s(refinery wastewater), K I(media) > K I(refinery wastewater); degradation kinetics, q max (media) > q max (refinery wastewater), K s(media) < K s(refinery wastewater), K I(media) > K I(refinery wastewater). The microalgae could cometabolize the alkane components present in refinery wastewater. Fourier transform infrared (FTIR) fingerprinting of biomass indicates intercellular phenol uptake and breakdown into its intermediates. Phenol was metabolized as an organic carbon source leading to higher specific growth rate of biomass. Phenol degradation pathway was elucidated using HPLC, liquid chromatography-mass spectrometry (LC-MS) and ultraviolet-visible (UV-visible) spectrophotometry. It involved both ortho- and meta-pathway with prominence of ortho-pathway. SEM analysis shows that cell membrane gets wrinkled on phenol exposure. Phenol degradation was growth and photodependent. Infrared analysis shows increased intracellular accumulation of neutral lipids opening possibility for utilization of spent biomass as biodiesel feedstock. The biomass after lipid extraction could be used as protein supplement in animal feed owing to enhanced protein content. The phenol remediation ability coupled with potential applicability of the spent biomass as biofuel feedstock and animal feed makes it a potential candidate for an environmentally sustainable process.

Wine phenolic compounds influence the production of volatile phenols by wine-related lactic acid bacteria.

PubMed

Silva, I; Campos, F M; Hogg, T; Couto, J A

2011-08-01

To evaluate the effect of wine phenolic compounds on the production of volatile phenols (4-vinylphenol [4VP] and 4-ethylphenol [4EP]) from the metabolism of p-coumaric acid by lactic acid bacteria (LAB). Lactobacillus plantarum, Lactobacillus collinoides and Pediococcus pentosaceus were grown in MRS medium supplemented with p-coumaric acid, in the presence of different phenolic compounds: nonflavonoids (hydroxycinnamic and benzoic acids) and flavonoids (flavonols and flavanols). The inducibility of the enzymes involved in the p-coumaric acid metabolism was studied in resting cells. The hydroxycinnamic acids tested stimulated the capacity of LAB to synthesize volatile phenols. Growth in the presence of hydroxycinnamic acids, especially caffeic acid, induced the production of 4VP by resting cells. The hydroxybenzoic acids did not significantly affect the behaviour of the studied strains. Some of the flavonoids showed an effect on the production of volatile phenols, although strongly dependent on the bacterial species. Relatively high concentrations (1 g l(-1) ) of tannins inhibited the synthesis of 4VP by Lact. plantarum. Hydroxycinnamic acids were the main compounds stimulating the production of volatile phenols by LAB. The results suggest that caffeic and ferulic acids induce the synthesis of the cinnamate decarboxylase involved in the metabolism of p-coumaric acid. On the other hand, tannins exert an inhibitory effect. This study highlights the capacity of LAB to produce volatile phenols and that this activity is markedly influenced by the phenolic composition of the medium. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Effect of maturity on phenolics (phenolic acids and flavonoids) profile of strawberry cultivars and mulberry species from Pakistan.

PubMed

Mahmood, Tahir; Anwar, Farooq; Abbas, Mateen; Saari, Nazamid

2012-01-01

In this study, we investigated how the extent of ripeness affects the yield of extract, total phenolics, total flavonoids, individual flavonols and phenolic acids in strawberry and mulberry cultivars from Pakistan. In strawberry, the yield of extract (%), total phenolics (TPC) and total flavonoids (TFC) ranged from 8.5-53.3%, 491-1884 mg gallic acid equivalents (GAE)/100 g DW and 83-327 mg catechin equivalents (CE)/100 g DW, respectively. For the different species of mulberry the yield of extract (%), total phenolics and total flavonoids of 6.9-54.0%, 201-2287 mg GAE/100 g DW and 110-1021 mg CE/100 g DW, respectively, varied significantly as fruit maturity progressed. The amounts of individual flavonols and phenolic acid in selected berry fruits were analyzed by RP-HPLC. Among the flavonols, the content of myricetin was found to be high in Morus alba (88 mg/100 g DW), the amount of quercetin as high in Morus laevigata (145 mg/100 g DW) while kaempferol was highest in the Korona strawberry (98 mg/100 g DW) at fully ripened stage. Of the six phenolic acids detected, p-hydroxybenzoic and p-coumaric acid were the major compounds in the strawberry. M. laevigata and M. nigra contained p-coumaric acid and vanillic acid while M. macroura and M. alba contained p-hydroxy-benzoic acid and chlorogenic acid as the major phenolic acids. Overall, a trend to an increase in the percentage of extraction yield, TPC, TFC, flavonols and phenolic acids was observed as maturity progressed from un-ripened to fully-ripened stages.

Virgin olive oil rich in phenolic compounds modulates the expression of atherosclerosis-related genes in vascular endothelium.

PubMed

Meza-Miranda, Eliana R; Rangel-Zúñiga, Oriol A; Marín, Carmen; Pérez-Martínez, Pablo; Delgado-Lista, Javier; Haro, Carmen; Peña-Orihuela, Patricia; Jiménez-Morales, Ana I; Malagón, María M; Tinahones, Francisco J; López-Miranda, José; Pérez-Jiménez, Francisco; Camargo, Antonio

2016-03-01

Previous studies have shown the anti-inflammatory and antioxidant properties of phenolic compounds of virgin olive oil (VOO). However, the effect of bioavailable phenolic compounds on the vascular endothelium is unknown. We aimed to evaluate the effect of the consumption of virgin olive oil rich in phenolic compounds on the vascular endothelium. We treated HUVEC with human serum obtained in fasting state and after the intake of a breakfast prepared with VOO with a high or low content of phenolic compounds. Treatment of HUVEC with serum obtained 2 h after the intake of the high-phenol VOO-based breakfast decreased p65 and MCP-1 gene expression (p < 0.001 and p = 0.002, respectively) and increased MT-CYB, SDHA and SOD1 gene expression (p = 0.004, p = 0.012 and p = 0.001, respectively), as compared with the treatment of HUVEC with the serum obtained 2 h after the intake of the low-phenol VOO-based breakfast. The treatment with serum obtained 4 h after the intake of the high-phenol VOO-based breakfast decreased MCP-1 and CAT gene expression (p < 0.001 and p = 0.003, respectively) and increased MT-CYB gene expression (p < 0.001), as compared to the treatment with serum obtained 4 h after the intake of the low-phenol VOO-based breakfast. Our results suggest that the consumption of virgin olive oil rich in phenolic compounds may reduce the risk of atherosclerosis development by decreasing inflammation and improving the antioxidant profile in the vascular endothelium.

Colonic catabolism of dietary phenolic and polyphenolic compounds from Concord grape juice.

PubMed

Stalmach, Angelique; Edwards, Christine A; Wightman, Jolynne D; Crozier, Alan

2013-01-01

After acute ingestion of 350 ml of Concord grape juice, containing 528 μmol of (poly)phenolic compounds, by healthy volunteers, a wide array of phase I and II metabolites were detected in the circulation and excreted in urine. Ingestion of the juice by ileostomists resulted in 40% of compounds being recovered intact in ileal effluent. The current study investigated the fate of these undigested (poly)phenolic compounds on reaching the colon. This was achieved through incubation of the juice using an in vitro model of colonic fermentation and through quantification of catabolites produced after colonic degradation and their subsequent absorption prior to urinary excretion by healthy subjects and ileostomy volunteers. A total of 16 aromatic and phenolic compounds derived from colonic metabolism of Concord grape juice (poly)phenolic compounds were identified by GC-MS in the faecal incubation samples. Thirteen urinary phenolic acids and aromatic compounds were excreted in significantly increased amounts after intake of the juice by healthy volunteers, whereas only two of these compounds were excreted in elevated amounts by ileostomists. The production of phenolic acids and aromatic compounds by colonic catabolism contributed to the bioavailability of Concord grape (poly)phenolic compounds to a much greater extent than phase I and II metabolites originating from absorption in the upper gastrointestinal tract. Catabolic pathways are proposed, highlighting the impact of colonic microbiota and subsequent phase II metabolism prior to excretion of phenolic compounds derived from (poly)phenolic compounds in Concord grape juice, which pass from the small to the large intestine.

UV-C and hyperoxia abiotic stresses to improve healthiness of carrots: study of combined effects.

PubMed

Formica-Oliveira, Anna Carolina; Martínez-Hernández, Ginés Benito; Aguayo, Encarna; Gómez, Perla A; Artés, Francisco; Artés-Hernández, Francisco

2016-09-01

Phenolic compounds are phytochemicals with high health-promoting properties. Carrot is a vegetable highly worldwide consumed although its phenolic content is low compared to other plant products. The aim of this work was to evaluate changes in phenolic compounds in carrots caused by abiotic stresses. The phenylalanine ammonia-lyase (PAL) activity, phenolic compounds and total antioxidant capacity (TAC) changes during storage up to 72 h at 15 °C after wounding (shredding), 9 kJ UV-C m -2 pretreatment and hyperoxia (80 kPa) conditions of carrots were studied. Shredding and hyperoxia storage induced the highest phenolic compounds and TAC enhancements. Accumulation of phenolic compounds in shredded carrots could be structured in the following phases: 1st phase (<24 h): unchanged phenolic compounds levels with minimum PAL activity; 2nd phase (24-48 h): moderate phenolic increases (≈600-700 mg CAE kg -1 accumulated in 24 h) concurring with the greatest increase of PAL activity; 3nd phase (48-72 h): high phenolic increases (≈1600-2700 mg CAE kg -1 , accumulated in 24 h) while a moderate increment of PAL activity was registered. Although UV-C pretreatment of shreds reduced phenolic accumulation, 600 % increments were still registered in those samples stored under hyperoxia conditions for 72 h. However, the contents of chlorogenic acid at 72 h were 1.4-fold higher in irradiated shreds under hyperoxia compared to the same samples under air conditions.

Optimization of extraction conditions of total phenolics, antioxidant activities, and anthocyanin of oregano, thyme, terebinth, and pomegranate.

PubMed

Rababah, Taha M; Banat, Fawzi; Rababah, Anfal; Ereifej, Khalil; Yang, Wade

2010-09-01

The purpose of this study was to evaluate the total phenolic extracts and antioxidant activity and anthocyanins of varieties of the investigated plants. These plants include oregano, thyme, terebinth, and pomegranate. The optimum extraction conditions including temperature and solvent of the extraction process itself were investigated. Total phenolic and anthocyanin extracts were examined according to Folin-Ciocalteu assay and Rabino and Mancinelli method, respectively. The effect of different extracting solvents and temperatures on extracts of phenolic compounds and anthocyanins were studied. Plant samples were evaluated for their antioxidant chemical activity by 2, 2-diphenyl-1-picrylhydrazl assay, to determine their potential as a source of natural antioxidant. Results showed that all tested plants exhibited appreciable amounts of phenolic compounds. The methanolic extract (60 °C) of sour pomegranate peel contained the highest phenolic extract (4952.4 mg/100 g of dry weight). Terebinth green seed had the lowest phenolic extract (599.4 mg/100 g of dry weight). Anthocyanins ranged between 3.5 (terebinth red seed) and 0.2 mg/100 g of dry material (thyme). Significant effect of different extracting solvents and temperatures on total phenolics and anthocyanin extracts were found. The methanol and 60 °C of extraction conditions found to be the best for extracting phenolic compounds. The distilled water and 60 °C extraction conditions found to be the best for extracting anthocyanin.

Spectrophotometric Determination of Phenolic Antioxidants in the Presence of Thiols and Proteins.

PubMed

Avan, Aslı Neslihan; Demirci Çekiç, Sema; Uzunboy, Seda; Apak, Reşat

2016-08-12

Development of easy, practical, and low-cost spectrophotometric methods is required for the selective determination of phenolic antioxidants in the presence of other similar substances. As electron transfer (ET)-based total antioxidant capacity (TAC) assays generally measure the reducing ability of antioxidant compounds, thiols and phenols cannot be differentiated since they are both responsive to the probe reagent. In this study, three of the most common TAC determination methods, namely cupric ion reducing antioxidant capacity (CUPRAC), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt/trolox equivalent antioxidant capacity (ABTS/TEAC), and ferric reducing antioxidant power (FRAP), were tested for the assay of phenolics in the presence of selected thiol and protein compounds. Although the FRAP method is almost non-responsive to thiol compounds individually, surprising overoxidations with large positive deviations from additivity were observed when using this method for (phenols + thiols) mixtures. Among the tested TAC methods, CUPRAC gave the most additive results for all studied (phenol + thiol) and (phenol + protein) mixtures with minimal relative error. As ABTS/TEAC and FRAP methods gave small and large deviations, respectively, from additivity of absorbances arising from these components in mixtures, mercury(II) compounds were added to stabilize the thiol components in the form of Hg(II)-thiol complexes so as to enable selective spectrophotometric determination of phenolic components. This error compensation was most efficient for the FRAP method in testing (thiols + phenols) mixtures.

Toxic and inhibitory effects of trichloroethylene aerobic co-metabolism on phenol-grown aerobic granules.

PubMed

Zhang, Yi; Tay, JooHwa

2015-04-09

Aerobic granule, a form of microbial aggregate, exhibits good potential in degrading toxic and recalcitrant substances. In this study, the inhibitory and toxic effects of trichloroethylene (TCE), a model compound for aerobic co-metabolism, on phenol-grown aerobic granules were systematically studied, using respiratory activities after exposure to TCE as indicators. High TCE concentration did not exert positive or negative effects on the subsequent endogenous respiration rate or phenol dependent specific oxygen utilization rate (SOUR), indicating the absence of solvent stress and induction effect on phenol-hydroxylase. Phenol-grown aerobic granules exhibited a unique response to TCE transformation product toxicity, that small amount of TCE transformation enhanced the subsequent phenol SOUR. Granules that had transformed between 1.3 and 3.7 mg TCE gSS(-1) showed at most 53% increase in the subsequent phenol SOUR, and only when the transformation exceeded 6.6 mg TCE gSS(-1) did the SOUR dropped below that of the control. This enhancing effect was found to sustain throughout several phenol dosages, and TCE transformation below the toxicity threshold also lessened the granules' sensitivity to higher phenol concentration. The unique toxic effect was possibly caused by the granule's compact structure as a protection barrier against the diffusive transformation product(s) of TCE co-metabolism. Copyright © 2015 Elsevier B.V. All rights reserved.

Variation in Phenolics, Flavanoids, Antioxidant and Tyrosinase Inhibitory Activity of Peach Blossoms at Different Developmental Stages.

PubMed

Liu, Jie-Chao; Jiao, Zhong-Gao; Yang, Wen-Bo; Zhang, Chun-Ling; Liu, Hui; Lv, Zhen-Zhen

2015-11-18

Peach blossoms were harvested and classified into six developmental stages: (I) bud emerging stage; (II) middle bud stage; (III) large bud stage; (IV) initial-flowering stage; (V) full-flowering stage; and (VI) end-flowering stage. The contents of total phenolics, flavanoids, individual phenolic compounds as well as antioxidant and tyrosinase inhibitory activity of peach blossoms at different developmental stages were investigated. The total phenolic contents varied from 149.80 to 74.80 mg chlorogenic acid equivalents/g dry weight (DW), and the total flavanoid contents ranged from 93.03 to 44.06 mg rutin equivalents/g DW. Both the contents of total phenolics and flavanoids decreased during blossom development. Chlorogenic acid was the predominant component, accounting for 62.08%-71.09% of the total amount of identified phenolic compounds in peach blossom. The antioxidant capacities determined by different assays and tyrosinase inhibitory activity also showed descending patterns during blossom development. Significant correlations were observed between antioxidant capacities with contents of total phenolics and total flavanoids as well as chlorogenic acid, cinnamic acid and kaempferol-3-O-galactoside, while the tyrosinase inhibitory activity had lower correlations with total phenolics and total flavanoids as well as chlorogenic acid, quercetin-3-O-rhamnoside, kaempferol-3-O-galactoside and cinnamic acid. The antioxidant activities of peach blossom seemed to be more dependent on the phenolic compounds than tyrosinase inhibitory activity.

Anaerobic Benzene Oxidation via Phenol in Geobacter metallireducens

PubMed Central

Tremblay, Pier-Luc; Chaurasia, Akhilesh Kumar; Smith, Jessica A.; Bain, Timothy S.; Lovley, Derek R.

2013-01-01

Anaerobic activation of benzene is expected to represent a novel biochemistry of environmental significance. Therefore, benzene metabolism was investigated in Geobacter metallireducens, the only genetically tractable organism known to anaerobically degrade benzene. Trace amounts (<0.5 μM) of phenol accumulated in cultures of Geobacter metallireducens anaerobically oxidizing benzene to carbon dioxide with the reduction of Fe(III). Phenol was not detected in cell-free controls or in Fe(II)- and benzene-containing cultures of Geobacter sulfurreducens, a Geobacter species that cannot metabolize benzene. The phenol produced in G. metallireducens cultures was labeled with 18O during growth in H218O, as expected for anaerobic conversion of benzene to phenol. Analysis of whole-genome gene expression patterns indicated that genes for phenol metabolism were upregulated during growth on benzene but that genes for benzoate or toluene metabolism were not, further suggesting that phenol was an intermediate in benzene metabolism. Deletion of the genes for PpsA or PpcB, subunits of two enzymes specifically required for the metabolism of phenol, removed the capacity for benzene metabolism. These results demonstrate that benzene hydroxylation to phenol is an alternative to carboxylation for anaerobic benzene activation and suggest that this may be an important metabolic route for benzene removal in petroleum-contaminated groundwaters, in which Geobacter species are considered to play an important role in anaerobic benzene degradation. PMID:24096430

Comparative Analysis of Chemical Composition, Antioxidant Activity and Quantitative Characterization of Some Phenolic Compounds in Selected Herbs and Spices in Different Solvent Extraction Systems.

PubMed

Sepahpour, Shabnam; Selamat, Jinap; Abdul Manap, Mohd Yazid; Khatib, Alfi; Abdull Razis, Ahmad Faizal

2018-02-13

This study evaluated the efficacy of various organic solvents (80% acetone, 80% ethanol, 80% methanol) and distilled water for extracting antioxidant phenolic compounds from turmeric, curry leaf, torch ginger and lemon grass extracts. They were analyzed regarding the total phenol and flavonoid contents, antioxidant activity and concentration of some phenolic compounds. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and the ferric reducing antioxidant power (FRAP) assay. Quantification of phenolic compounds was carried out using high-performance liquid chromatography (HPLC). All the extracts possessed antioxidant activity, however, the different solvents showed different efficiencies in the extraction of phenolic compounds. Turmeric showed the highest DPPH values (67.83-13.78%) and FRAP (84.9-2.3 mg quercetin/g freeze-dried crude extract), followed by curry leaf, torch ginger and lemon grass. While 80% acetone was shown to be the most efficient solvent for the extraction of total phenolic compounds from turmeric, torch ginger and lemon grass (221.68, 98.10 and 28.19 mg GA/g freeze dried crude extract, respectively), for the recovery of phenolic compounds from curry leaf (92.23 mg GA/g freeze-dried crude extract), 80% ethanol was the most appropriate solvent. Results of HPLC revealed that the amount of phenolic compounds varied depending on the types of solvents used.

Effect of solvent on the extraction of phenolic compounds and antioxidant capacity of hazelnut kernel.

PubMed

Fanali, Chiara; Tripodo, Giusy; Russo, Marina; Della Posta, Susanna; Pasqualetti, Valentina; De Gara, Laura

2018-03-22

Hazelnut kernel phenolic compounds were recovered applying two different extraction approaches, namely ultrasound-assisted solid/liquid extraction (UA-SLE) and solid-phase extraction (SPE). Different solvents were tested evaluating total phenolic compounds and total flavonoids contents together to antioxidant activity. The optimum extraction conditions, in terms of the highest value of total phenolic compounds extracted together to other parameters like simplicity and cost were selected for method validation and individual phenolic compounds analysis. The UA-SLE protocol performed using 0.1 g of defatted sample and 15 mL of extraction solvent (1 mL methanol/1 mL water/8 mL methanol 0.1% formic acid/5 mL acetonitrile) was selected. The analysis of hazelnut kernel individual phenolic compounds was obtained by HPLC coupled with DAD and MS detections. Quantitative analysis was performed using a mixture of six phenolic compounds belonging to phenolic classes' representative of hazelnut. Then, the method was fully validated and the resulting RSD% values for retention time repeatability were below 1%. A good linearity was obtained giving R 2 no lower than 0.997.The accuracy of the extraction method was also assessed. Finally, the method was applied to the analysis of phenolic compounds in three different hazelnut kernel varieties observing a similar qualitative profile with differences in the quantity of detected compounds. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phenolic Compounds in Particles of Mainstream Waterpipe Smoke

PubMed Central

2013-01-01

Introduction: Waterpipe tobacco smoking has in recent years become a popular international phenomenon, particularly among youth. While it has been shown to deliver significant quantities of several carcinogenic and toxic substances, phenols, an important class of chemical compounds thought to promote DNA mutation and cardiovascular diseases, however, has not been studied. Due to the relatively low temperature characteristic of waterpipe tobacco during smoking (i.e., <450 °C), it was hypothesized that phenolic compounds, which form at approximately 300 °C, will be found in abundance in waterpipe smoke. Methods: In this study, phenolic compounds in the particle phase of waterpipe mainstream smoke were quantified. Waterpipe and cigarette mainstream smoke generated using standard methods were collected on glass fiber pads and analyzed using gas chromatography/mass spectroscopy selected ion current profile chromatogram method for quantification. Results: We found that relative to a single cigarette, a waterpipe delivers at least 3 times greater quantities of the 7 analyzed phenols (phenol, o-cresol, m-cresol, p-cresol, catechol, resorcinol, and hydroquinone). Moreover, phenol derivatives such as methylcatechol, and flavorings such as vanillin, ethyl vanillin, and benzyl alcohol were found in quantities up to 1,000 times greater than the amount measured in the smoke of a single cigarette. Conclusion: The large quantities of phenols and phenol derivatives in waterpipe smoke add to the growing evidence that habitual waterpipe use may increase the risk of cancer and cardiovascular diseases. PMID:23178319

Effect of drying of figs (Ficus carica L.) on the contents of sugars, organic acids, and phenolic compounds.

PubMed

Slatnar, Ana; Klancar, Urska; Stampar, Franci; Veberic, Robert

2011-11-09

Fresh figs were subjected to two different drying processes: sun-drying and oven-drying. To assess their effect on the nutritional and health-related properties of figs, sugars, organic acids, single phenolics, total phenolics, and antioxidant activity were determined before and after processing. Samples were analyzed three times in a year, and phenolic compounds were determined using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS). In figs, monomer sugars predominate, which is important nutritional information, and the content of sugars as well as organic acids in fresh figs was lower than in dried fruits. However, the best sugar/organic acid ratio was measured after the sun-drying process. Analysis of individual phenolic compounds revealed a higher content of all phenolic groups determined after the oven-drying process, with the exception of cyanidin-3-O-rutinoside. Similarly, higher total phenolic content and antioxidant activity were detected after the drying process. With these results it can be concluded that the differences in analyzed compounds in fresh and dried figs are significant. The differences between the sun-dried and oven-dried fruits were determined in organic acids, sugars, chlorogenic acid, catechin, epicatechin, kaempferol-3-O-glucoside, luteolin-8-C-glucoside, and total phenolic contents. The results indicate that properly dried figs can be used as a good source of phenolic compounds.

What makes A. guillouiae SFC 500-1A able to co-metabolize phenol and Cr(VI)? A proteomic approach.

PubMed

Ontañon, Ornella Mailén; Landi, Claudia; Carleo, Alfonso; Gagliardi, Assunta; Bianchi, Laura; González, Paola Solange; Agostini, Elizabeth; Bini, Luca

2018-04-27

Acinetobacter guillouiae SFC 500-1A is an environmental bacterium able to efficiently co-remediate phenol and Cr(VI). To further understand the molecular mechanisms triggered in this strain during the bioremediation process, variations in the proteomic profile after treatment with phenol and phenol plus Cr(VI) were evaluated. The proteomic analysis revealed the induction of the β-ketoadipate pathway for phenol oxidation and the assimilation of degradation products through TCA cycle and glyoxylate shunt. Phenol exposure increased the abundance of proteins associated to energetic processes and ATP synthesis, but it also triggered cellular stress. The lipid bilayer was suggested as a target of phenol toxicity, and changing fatty acids composition seemed to be the bacterial response to protect the membrane integrity. The involvement of two flavoproteins in Cr(VI) reduction to Cr(III) was also proposed. The results suggested the important role of chaperones, antioxidant response and SOS-induced proteins in the ability of the strain to mitigate the damage generated by phenol and Cr(VI). This research contributes to elucidate the mechanisms involved in A. guillouiae SFC 500-1A tolerance and co-remediation of phenol and Cr(VI). Such information may result useful not only to improve its bioremediation efficiency but also to identify putative markers of resistance in environmental bacteria. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of steam explosion-assisted extraction on phenolic acid profiles and antioxidant properties of wheat bran.

PubMed

Liu, Liya; Zhao, Mengli; Liu, Xingxun; Zhong, Kui; Tong, Litao; Zhou, Xianrong; Zhou, Sumei

2016-08-01

The majority of phenolic acids in wheat bran are bound to the cell walls. Hence, a high proportion of phenolic acids cannot be extracted with conventional extraction methods. This study aimed to investigate the efficiency of steam explosion pre-treatment in increasing the extractability of phenolic compounds from wheat bran. Bound phenolic acids (BPA) can be released by steam explosion-assisted extraction. Within the experimental range, soluble free phenolic acids (FPA) and soluble conjugated phenolic acids (CPA) increased gradually with residence time and temperature. After steam explosion at 215 °C for 120 s, the total FPA and CPA reached 6671.8 and 2578.6 µg GAE g(-1) bran, respectively, which was about 39-fold and seven-fold higher than that of the untreated sample. Ferulic acid, the major individual phenolic acids in bran, increased from 55.7 to 586.3 µg g(-1) for FPA, and from 44.9 to 1108.4 µg g(-1) for CPA. The antioxidant properties of FPA and CPA extracts were significantly improved after treated. Correlation analysis indicated that the antioxidant capacity was in close relationship with phenolic content in FPA and CPA. Steam explosion pre-treatment could be effectively used to release of BPA and enhance the antioxidant capacity of wheat bran. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Variations of total phenol, carotenoid, in vitro antioxidant contents, and phenolic profiles of the pulp of five commercial varieties of mango (Mangifera indica L.)

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in mango peel, seeds, and leaves, yet less is known about the phenolic antioxi...

Preparation and Characterization of Novolak Phenol Formaldehyde Resin from Liquefied Brown-Rotted Wood

Treesearch

Gai-Yun Li; Chung-Yun Hse; Te-Fu Qin

2012-01-01

The brown-rotted wood was liquefied in phenol with phosphoric acid as catalyst and the resulting liquefied products were condensed with formaldehyde to yield novolak liquefied wood-based phenol formaldehyde resin (LWPF). The results showed that brown-rotted wood could be more easily liquefied than sound wood in phenol. The residue content of liquefied wood decreased...

Synthesis of phenol-urea-formaldehyde cocondensed resins from UF-concentrate and phenol

Treesearch

Bunchiro Tomita; Mashiko Ohyama; Chung-Yun Hse

1994-01-01

A new synthetic method to obtain phenol-urea-formaldehyde cocondensed resins was developed by reacting phenol with "UF-concentrate", which is a kind of urea-formaldehyde (UF) resin prepared with a high molar ratio of formaldehyde to urea (F/U) such as above 2.5. The products were analyzed with 13C-NMR spectroscopy and gel permeation...

Synthesis, chemical characterization, and economical feasibility of poly-phenolic-branched-chain fatty acids: Synthesis of poly-phenolic-branched-chain fatty acids

USDA-ARS?s Scientific Manuscript database

New poly-phenolic branched-chain fatty acid (poly-PBC-FA) products were synthesized from a combination of soybean fatty acids and phenolic materials through a highly efficient zeolite catalyzed arylation method. These poly-PBC-FAs are liquid at room temperature and do not have the unpleasant odor li...

Predicting the reactivity of phenolic compounds with formaldehyde. II, continuation of an ab initio study.

Treesearch

Tohru Mitsunaga; Anthony H. Conner; Charles G. Jr. Hill

2002-01-01

Phenol–formaldehyde resins are important adhesives used by the forest products industry. The phenolic compounds in these resins are derived primarily from petrochemical sources. Alternate sources of phenolic compounds include tannins, lignins, biomass pyrolysis products, and coal gasification products. Because of variations in their chemical structures, the...

[Identification of migrants from nitrile-butadiene rubber gloves].

PubMed

Mutsuga, Motoh; Kawamura, Yoko; Wakui, Chiseko; Maitani, Tamio

2003-04-01

Polyvinyl chloride gloves containing di(2-ethylhexyl) phthalate are restricted for food contact use. In their place, disposable gloves made from nitrile-butadiene rubber (NBR) are used in contact with foodstuffs. Some unknown substances were found to migrate into n-heptane from NBR gloves. By GC/MS, HR-MS and NMR, their chemical structures were confirmed to be 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (used as a plasticizer), 4,4'-butylidenedi(6-tert-butyl-m-cresol), a mixture of styrenated phenols consisting of 2-(alpha-methylbenzyl)phenol, 4-(alpha-methylbenzyl)phenol, 2,6-di(alpha-methylbenzyl)phenol, 2,4-di(alpha-methylbenzyl)phenol and 2,4,6-tri(alpha-methylbenzyl)phenol (used as antioxidants), and 2,4-di-tert-butylphenol, which seems to a degradation product of antioxidant. Migration levels of these compounds were 1.68 micrograms/cm2 of 2,4-di-tert-butylphenol, 2.80 micrograms/cm2 of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, 46.08 micrograms/cm2 of styrenated phenols and 4.22 micrograms/cm2 of 4,4'-butylidenedi(6-tert-butyl-m-cresol) into n-heptane, respectively. The content of total styrenated phenols was 6,900 micrograms/g in NBR gloves.

Turnover capacity of Coprinus cinereus peroxidase for phenol and monosubstituted phenols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aitken, M.D.; Heck, P.E.

Coprinus cinereus peroxidase (CIP) and other peroxidases are susceptible to mechanism-based inactivation during the oxidation of phenolic substrates. The turnover capacity of CIP was quantified for phenol and 11 monosubstituted phenols under conditions in which enzyme inactivation by mechanisms involving hydrogen peroxide alone were minimized. Turnover capacities varied by nearly 2 orders of magnitude, depending on the substituent. On a mass basis, the enzyme consumption corresponding to the lowest turnover capacities is considerable and may influence the economic feasibility of proposed industrial applications of peroxidases. Within a range of substituent electronegativity values, molar turnover capacities correlated well (r{sup 2} =more » 0.89) with substituent effects quantified by radical {sigma} values and semiquantitatively with homolytic O-H bond dissociation energies of the phenolic substrates, suggesting that phenoxyl radical intermediates are probably involved in the suicide inactivation of CIP. The correlation range in each case did not include phenols with highly electron-withdrawing (nitro and cyano) substituents because they are not oxidized by CIP, nor phenols with highly electron-donating (hydroxy and amino) substituents because they led to virtually complete inactivation of the enzyme with minimal substrate removal.« less

Toxicity of phenol and monochlorophenols to growth and metabolic activities of Pseudomonas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, D.S.; Tseng, I.C.

1996-07-01

Phenolic compounds are toxic to many organisms and are often present in the effluents from oil refineries, the petrochemical, pesticide, and color and textile industries. Several authors have demonstrated a characteristic pattern of behavioral responses in fishes during phenol exposure. Others have also evaluated the toxicity of halogenated phenolic compounds by screening for effects on the specific growth rates (SGR) and the dehydrogenase activity (DHA) of Escherichia coli. However, little work has been done to determine the effects on biota from short exposures at relatively high concentrations of phenol or monochlorophenols that might occur following a deliberate or accidental dischargemore » to a receiving water. Microorganisms with phenol-degrading capacity have been studied intensively, including cyanobacteria such as Nostoc linckia, yeast such as Trichosporon cutaneum, bacteria such as Pseudomonas putida, and other unidentified species. Among these Pseudomonas has received the most attention and several mutants have been prepared to degrade substituted phenols. This study investigates the initial response of Pseudomonas upon exposure to high concentrations of phenol and chlorophenols by measuring the oxygen uptake rates. A series growth experiment was also conducted in order to compare the kinetic results with standard microbial tests. 12 refs., 3 figs., 1 tab.« less

Mechanism for the oxidation of phenol by sulfatoferrate(VI): Comparison with various oxidants.

PubMed

Peings, Vanessa; Frayret, Jérôme; Pigot, Thierry

2015-07-01

The oxidative action of a solid and stable potassium sulfatoferrate(VI) material on phenol was studied in aqueous solution under different stoichiometries. The performance towards phenol and the total organic carbon is compared to that of potassium permanganate and calcium hypochlorite. The total mineralization of phenol is not completely achieved by the studied chemical oxidants, and some oxidation products have been identified by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector analysis. A radical reaction pathway, involving the formation of oxidation intermediates or by-products such as benzoquinone, phenoxyphenol and ring opening products, is proposed for the decomposition of phenol by ferrate(VI). Phenoxyphenol is also involved in the oxidation mechanism for permanganate whereas chlorinated phenols are produced by hypochlorite. The role of the chloride anion impurity of the potassium sulfatoferrate(VI) material has been highlighted in this study; no negative impact on the removal of phenol and its mineralization is observed compared to the use of a pure commercial ferrate(VI). The efficiency of sulfatoferrate(VI) for the oxidative removal of phenol from industrial wastewater is also confirmed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phenolic content and antioxidant properties of seeds from different grape cultivars grown in Iran.

PubMed

Mirbagheri, Vasigheh Sadat; Alizadeh, Ebrahim; Yousef Elahi, Mostafa; Esmaeilzadeh Bahabadi, Sedigheh

2018-02-01

This study investigated the antioxidant activity and phenolic composition of seed extracts from three grape cultivars grown in Iran. Folin Ciocalteu method was used for the determination of the total phenolic contents and GC-MS was used for the analysis of phenolic compositions. 1,1-diphenyl-2-picrylhydrazyl (DPPH) method was used to evaluate the antioxidant activity. The highest and the lowest total phenolic contents of seed extract were found in the black and green grape, respectively. The content of individual phenols such as Frulic acid, Gentistic acid, Syringic acid, (+) Catechin, Chlorogenic acid and (-)- Epicatchin gallate was cultivars dependent. The antioxidant activity of the seed extracts ranged from 34.03% (Green) to 53.63% (Black). Generally, the Black grape seed extract with the total phenolic content (3 ± 0.01 mg tannic acid/g DM), DPPH (53.63 ± 0.34%), IC 50 and AEAC (7.41 and 16.92 mg/mL) showed the highest level of total antioxidant capacity.

Profile and antioxidant activity of phenolic extracts from 10 crabapples (Malus wild species).

PubMed

Li, Nan; Shi, Junling; Wang, Kun

2014-01-22

Phenolic products are highly demanded by the food and cosmetics industries and consumers due to their high antioxidant activities. To evaluate the potential of crabapples (Malus wild species) in preparing phenolic extracts, fruits of 10 crabapples grown in China were separately extracted with 80% (v/v) ethanol and ethyl acetate and the phenolic profiles, polyphenol (PC) and flavonoid contents (FC), and antioxidant activities of the extracts were analyzed. Chlorogenic acid, (-)-epicatechin, rutin, hyperin, and phlorizin appeared as the major phenolic compounds in all phenolic extracts. Ethanol extracts had PC of 302.83-1265.94 mg GAE/100g and FC of 352.45-2351.74 mg RE/100g, being 4.17 and 4.49 times those obtained in ethyl acetate extracts and much higher than those previously reported in apples. Malus wild species appeared as rich sources of phenolic compounds with high antioxidant activity, especially when high chlorogenic acid and rutin contents are emphasized.

Histopathological effects of phenol on the digestive gland of amphimelania holandri fer. (gastropoda, prosobranchia)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lajtner, J.; Erben, R.; Klobucar, G.I.V.

1996-12-31

Phenolic wastes are common water pollutants generated from a variety of industrial processes used in oil refineries, gas operations, coke ovens, coal gasification and by natural processes such as the decomposition of plant matter. Relatively high concentrations of phenol are found in rivers near the outlets of channels into which industrial waste waters have been discharged. There are data about the toxic effects of phenol on fish, and on some invertebrates, including snails. However, little is known about histopathological changes induced by phenol`s toxic effects, and these changes might be a basic indicator in assessing the condition of a particularmore » water ecosystem. The existing data are mostly relevant for fish, and we know very little about the snail`s histopathology; however, the snail is a good research model due to its effectiveness as a pollution indicator species. This study attempts to establish the structure of the normal digestive gland and histopathological changes as a result of exposure to phenol. 22 refs., 4 figs.« less

Home Cooking and Phenolics: Effect of Thermal Treatment and Addition of Extra Virgin Olive Oil on the Phenolic Profile of Tomato Sauces.

PubMed

Vallverdú-Queralt, Anna; Regueiro, Jorge; Rinaldi de Alvarenga, José Fernando; Torrado, Xavier; Lamuela-Raventos, Rosa M

2014-04-09

Tomato products are a key component of the Mediterranean diet, which is strongly related to a reduced risk of cardiovascular events. The effect of cooking time (15, 30, 45, and 60 min) and the addition of extra virgin olive oil (5 and 10%) on the phenolic content of tomato sauces was monitored using liquid chromatography coupled to tandem mass spectrometry. Concentration of phenolics in the tomato sauces decreased during the cooking process, with the exception of caffeic acid and tyrosol. The main degradation observed was the oxidation of quercetin, since the hydroxy-function at the C-ring of this flavonoid is not blocked by a sugar moiety, unlike rutin. Higher levels of virgin olive oil in tomato sauce seemed to enhance the extraction of phenolic compounds from the tomato, leading to higher phenolic contents in the sauces. Thus, the food matrix containing the phenolic compounds plays a crucial role in determining their accessibility.

Monitoring endogenous enzymes during olive fruit ripening and storage: correlation with virgin olive oil phenolic profiles.

PubMed

Hachicha Hbaieb, Rim; Kotti, Faten; García-Rodríguez, Rosa; Gargouri, Mohamed; Sanz, Carlos; Pérez, Ana G

2015-05-01

The ability of olive endogenous enzymes β-glucosidase, polyphenol oxidase (PPO) and peroxidase (POX), to determine the phenolic profile of virgin olive oil was investigated. Olives used for oil production were stored for one month at 20 °C and 4 °C and their phenolic content and enzymatic activities were compared to those of ripening olive fruits. Phenolic and volatile profiles of the corresponding oils were also analysed. Oils obtained from fruits stored at 4 °C show similar characteristics to that of freshly harvested fruits. However, the oils obtained from fruits stored at 20 °C presented the lowest phenolic content. Concerning the enzymatic activities, results show that the β-glucosidase enzyme is the key enzyme responsible for the determination of virgin olive oil phenolic profile as the decrease in this enzyme activity after 3 weeks of storage at 20 °C was parallel to a dramatic decrease in the phenolic content of the oils. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemistry and health of olive oil phenolics.

PubMed

Cicerale, Sara; Conlan, Xavier A; Sinclair, Andrew J; Keast, Russell S J

2009-03-01

The Mediterranean diet is associated with a lower incidence of atherosclerosis, cardiovascular disease, and certain types of cancer. The apparent health benefits have been partially attributed to the dietary consumption of virgin olive oil by Mediterranean populations. Most recent interest has focused on the biologically active phenolic compounds naturally present in virgin olive oils. Studies (human, animal, in vivo and in vitro) have shown that olive oil phenolics have positive effects on certain physiological parameters, such as plasma lipoproteins, oxidative damage, inflammatory markers, platelet and cellular function, and antimicrobial activity. Presumably, regular dietary consumption of virgin olive oil containing phenolic compounds manifests in health benefits associated with a Mediterranean diet. This paper summarizes current knowledge on the physiological effects of olive oil phenolics. Moreover, a number of factors have the ability to affect phenolic concentrations in virgin olive oil, so it is of great importance to understand these factors in order to preserve the essential health promoting benefits of olive oil phenolic compounds.

Artificial neural network modelling of the antioxidant activity and phenolic compounds of bananas submitted to different drying treatments.

PubMed

Guiné, Raquel P F; Barroca, Maria João; Gonçalves, Fernando J; Alves, Mariana; Oliveira, Solange; Mendes, Mateus

2015-02-01

Bananas (cv. Musa nana and Musa cavendishii) fresh and dried by hot air at 50 and 70°C and lyophilisation were analysed for phenolic contents and antioxidant activity. All samples were subject to six extractions (three with methanol followed by three with acetone/water solution). The experimental data served to train a neural network adequate to describe the experimental observations for both output variables studied: total phenols and antioxidant activity. The results show that both bananas are similar and air drying decreased total phenols and antioxidant activity for both temperatures, whereas lyophilisation decreased the phenolic content in a lesser extent. Neural network experiments showed that antioxidant activity and phenolic compounds can be predicted accurately from the input variables: banana variety, dryness state and type and order of extract. Drying state and extract order were found to have larger impact in the values of antioxidant activity and phenolic compounds. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phenolic Compounds in the Potato and Its Byproducts: An Overview

PubMed Central

Akyol, Hazal; Riciputi, Ylenia; Capanoglu, Esra; Caboni, Maria Fiorenza; Verardo, Vito

2016-01-01

The potato (Solanum tuberosum L.) is a tuber that is largely used for food and is a source of different bioactive compounds such as starch, dietary fiber, amino acids, minerals, vitamins, and phenolic compounds. Phenolic compounds are synthetized by the potato plant as a protection response from bacteria, fungi, viruses, and insects. Several works showed that these potato compounds exhibited health-promoting effects in humans. However, the use of the potato in the food industry submits this vegetable to different processes that can alter the phenolic content. Moreover, many of these compounds with high bioactivity are located in the potato’s skin, and so are eliminated as waste. In this review the most recent articles dealing with phenolic compounds in the potato and potato byproducts, along with the effects of harvesting, post-harvest, and technological processes, have been reviewed. Briefly, the phenolic composition, main extraction, and determination methods have been described. In addition, the “alternative” food uses and healthy properties of potato phenolic compounds have been addressed. PMID:27240356

Degradation and Mineralization of Phenol Compounds with Goethite Catalyst and Mineralization Prediction Using Artificial Intelligence

PubMed Central

Tisa, Farhana; Davoody, Meysam; Abdul Raman, Abdul Aziz; Daud, Wan Mohd Ashri Wan

2015-01-01

The efficiency of phenol degradation via Fenton reaction using mixture of heterogeneous goethite catalyst with homogeneous ferrous ion was analyzed as a function of three independent variables, initial concentration of phenol (60 to 100 mg /L), weight ratio of initial concentration of phenol to that of H2O2 (1: 6 to 1: 14) and, weight ratio of initial concentration of goethite catalyst to that of H2O2 (1: 0.3 to 1: 0.7). More than 90 % of phenol removal and more than 40% of TOC removal were achieved within 60 minutes of reaction. Two separate models were developed using artificial neural networks to predict degradation percentage by a combination of Fe3+ and Fe2+ catalyst. Five operational parameters were employed as inputs while phenol degradation and TOC removal were considered as outputs of the developed models. Satisfactory agreement was observed between testing data and the predicted values (R2 Phenol = 0.9214 and R2TOC= 0.9082). PMID:25849556

Assessment of the differences in the phenolic composition and color characteristics of new strawberry (Fragaria x ananassa Duch.) cultivars by HPLC-MS and Imaging Tristimulus Colorimetry.

PubMed

Fernández-Lara, Rebeca; Gordillo, Belén; Rodríguez-Pulido, Francisco J; Lourdes González-Miret, M; Del Villar-Martínez, Alma A; Dávila-Ortiz, Gloria; Heredia, Francisco J

2015-10-01

The phenolic composition (by HPLC-DAD-MS) and color characteristics (by Imaging Tristimulus Colorimetry) of four strawberry cultivars that have shown good climate adaptation to subtropical area (Nikte, Zamorana, Jacona and Pakal) have been assessed. 24 monomeric phenolics were identified, including 15 anthocyanins, 5 phenolic acids, 1 flavanol and 4 flavonols. Nikte and Zamorana showed the highest phenolic potential mainly due to their higher content of anthocyanins, while Pakal was richer in phenolic acids. Regarding color, Nikte and Zamorana were the more similar cultivars having the lowest values of lightness and hue. On the contrary, the color of Pakal was quite different from all the rest, due to the specific distribution between pelargonidin and cyanidin. The inclusion of both phenolic and colorimetric information in the Linear Discriminant Analysis allowed reaching very good discriminations among cultivars. Copyright © 2015 Elsevier Ltd. All rights reserved.

Plant Phenols as Antibiotic Boosters: In Vitro Interaction of Olive Leaf Phenols with Ampicillin.

PubMed

Lim, Anxy; Subhan, Nusrat; Jazayeri, Jalal A; John, George; Vanniasinkam, Thiru; Obied, Hassan K

2016-03-01

The antimicrobial properties of olive leaf extract (OLE) have been well recognized in the Mediterranean traditional medicine. Few studies have investigated the antimicrobial properties of OLE. In this preliminary study, commercial OLE and its major phenolic secondary metabolites were evaluated in vitro for their antimicrobial activities against Escherichia coli and Staphylococcus aureus, both individually and in combination with ampicillin. Besides luteolin 7-O-glucoside, OLE and its major phenolic secondary metabolites were effective against both bacteria, with more activity on S. aureus. In combination with ampicillin, OLE, caffeic acid, verbascoside and oleuropein showed additive effects. Synergistic interaction was observed between ampicillin and hydroxytyrosol. The phenolic composition of OLE and the stability of olive phenols in assay medium were also investigated. While OLE and its phenolic secondary metabolites may not be potent enough as stand-alone antimicrobials, their abilities to boost the activity of co-administered antibiotics constitute an imperative future research area. Copyright © 2016 John Wiley & Sons, Ltd.

Bioaccessibility and potential bioavailability of phenolic compounds from achenes as a new target for strawberry breeding programs.

PubMed

Ariza, María Teresa; Reboredo-Rodríguez, Patricia; Cervantes, Lucía; Soria, Carmen; Martínez-Ferri, Elsa; González-Barreiro, Carmen; Cancho-Grande, Beatriz; Battino, Maurizio; Simal-Gándara, Jesús

2018-05-15

Strawberry is a major natural source of bioactive compounds. Botanically, strawberry is an aggregate fruit consisting of a fleshy floral receptacle that bears a cluster of real dry fruits (achenes). Existing knowledge on the phenolic composition of achenes and its contribution to that of the whole fruit is limited. Also, the gastric and intestinal bioavailability of phenols is poorly known. In this work, a combination of spectrophotometric and HPLC-DAD methods was used to analyse the phenolic composition of whole fruits and achenes before and after in vitro digestion. Five different phenol families were identified. Also, achenes were found to contribute a sizeable fraction of phenolic acids and hydrolysable tannins in the whole fruit. Because the mere presence of phenolic compounds in a food matrix does not ensure their ready absorption and bioavailability, polyphenol potential bioavailability could be an effective selection criterion for strawberry breeding programs aimed at improving dietary healthiness. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of antioxidant activity, total phenolics, total flavonoids and LC-MS/MS characterisation of phenolic constituents in Stachys lavandulifolia.

PubMed

Rahimi Khoigani, Soroush; Rajaei, Ahmad; Goli, Sayed Amir Hossein

2017-02-01

The aim of this study was to evaluate phenolics profile and antioxidant activity of Stachys lavandulifolia. Total phenolics (TP), total flavonoids (TF), DPPH• assay (IC50), ferric ion reducing antioxidant power (FRAP) and total antioxidant capacity (TAC) of the methanolic extract were measured. The content of TP, TF, IC50, FRAP and TAC, were obtained as 16.59 gallic acid equiv./g dry matter (DM), 4.48 mg quercetin equiv./g DM, 2.07 (μg/mL), 0.014 (absorbance/mg phenolic) and 14.61 (mg BHT equiv./g DM), respectively. The results showed that S. lavandulifolia, compared to other species of Stachys, had moderate TP content with desirable antioxidant activity. Subsequently, 59 various phenolic compounds were identified and confirmed in the methanolic extract of S. lavandulifolia using high mass accuracy by MS2 experiments. The compounds consisted of 6 hydroxybenzoic acids and hydroxybenzoic aldehydes, 9 hydroxycinnamic acids, 1 coumarin, 32 flavonoids, 3 lignans, 2 stilbenes, 3 tannins and 3 other phenolics.

Comparison of phenolic content and antioxidant activities of millet varieties grown in different locations in Sri Lanka.

PubMed

Kumari, Disna; Madhujith, Terrence; Chandrasekara, Anoma

2017-05-01

Soluble and bound phenolic compounds were extracted from different varieties of millet types namely, finger millet, foxtail, and proso millet cultivated at dry and intermediate climatic zones in Sri Lanka. The extracts were examined for their total phenolic content (TPC), total flavonoid content (TFC), and proanthocyanidin content (PC). The antioxidant activities were meassured by reducing power (RP), trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferrous ion chelating ability (FICA), and using a β carotene linoleate model system. The ferulic acid content of extracts were determined using high-performance liquid chromatoghraphy (HPLC). Finger millet showed the highest phenolic content and antioxidant activities compared to proso and foxtail millets. The phenolic content as well as antioxidant activites of soluble and bound phenolic extracts of millets were affected by variety and cultivated location. The highest phenolic content and antioxidant activites were reported for millet samples cultivated in areas belonging to the dry zone in Sri Lanka.

Effect of operational factors on bioregeneration of binary phenol and 4-chlorophenol-loaded granular activated carbon using PVA-immobilized biomass cryogels.

PubMed

Leong, Kwok-Yii; Adnan, Rohana; Lim, Poh-Eng; Ng, Si-Ling; Seng, Chye-Eng

2017-09-01

The effects of dry biomass density in cryogel beads, shaking speed and initial concentration ratio of phenol to 4-chlorophenol (4-CP) on the bioregeneration efficiencies of binary phenol and 4-CP-loaded granular activated carbon (GAC) for phenol and 4-CP, respectively, were investigated under the simultaneous adsorption and biodegradation approach. The results revealed higher bioregeneration efficiencies of binary-loaded GAC for phenol and 4-CP at higher dry biomass density but moderate shaking speed. The optimum dry biomass density in cryogel beads and shaking speed for use in bioregeneration were found to be 0.01 g/mL and 250 rpm, respectively. With respect to the initial phenol to 4-CP concentration ratio, the bioregeneration efficiencies were lower under increasing phenol and 4-CP initial concentrations, respectively, with the effect being more conspicuous under increasing 4-CP concentration. Higher bioregeneration efficiencies were achieved with the use of immobilized rather than suspended biomasses.

Phenolic profile and fermentation patterns of different commercial gluten-free pasta during in vitro large intestine fermentation.

PubMed

Rocchetti, Gabriele; Lucini, Luigi; Chiodelli, Giulia; Giuberti, Gianluca; Gallo, Antonio; Masoero, Francesco; Trevisan, Marco

2017-07-01

The fate of phenolic compounds, along with short-chain fatty acids (SCFAs) production kinetics, was evaluated on six different commercial gluten-free (GF) pasta samples varying in ingredient compositions, focussing on the in vitro faecal fermentation after the gastrointestinal digestion. A general reduction of both total phenolics and reducing power was observed in all samples, together with a substantial change in phenolic profile over 24h of faecal fermentation, with differences among GF pasta samples. Flavonoids, hydroxycinnamics and lignans degraded over time, with a concurrent increase in low-molecular-weight phenolic acids (hydroxybenzoic acids), alkylphenols, hydroxybenzoketones and tyrosols. Interestingly, discriminant analysis also identified several alkyl derivatives of resorcinol as markers of the changes in phenolic profile during in vitro fermentation. Furthermore, degradation pathways of phenolics by intestinal microbiota have been proposed. Considering the total SCFAs and butyrate production during the in vitro fermentation, different fermentation kinetics were observed among GF pasta post-hydrolysis residues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phenolic metabolites of grape antioxidant dietary fiber in rat urine.

PubMed

Touriño, Sonia; Fuguet, Elisabet; Vinardell, María Pilar; Cascante, Marta; Torres, Josep Lluís

2009-12-09

Grape antioxidant dietary fiber (GADF) combines the putative health benefits of fiber and polyphenols. Polyphenolic metabolites may play a key role in the overall biological effects of this supplement. We identified phenolic GADF metabolites in rat urine at different times after oral administration, using HPLC-ESI-MS/MS techniques. The phenolic metabolic outcome of GADF is essentially an array of mono- and polyconjugated epicatechins and free or conjugated smaller phenolic acids, some of them never reported before. We have detected 18 mono-, di-, and triconjugates of epicatechin with glucuronide, methyl and sulfate moieties and small phenolic acids both free and conjugated. The results suggest that the procyanidin oligomers are both depolymerized in the digestive tract into epicatechin conjugates and degraded by the colonic microbiota into phenolic acids and their conjugates. For several hours after ingestion of GADF, a great variety of phenolic species, including some with an intact catechol group, are in contact with the digestive tract tissues before, during and after metabolization, and many of them are systemically bioavailable before being excreted.

Comparative study of antioxidant properties and total phenolic content of 30 plant extracts of industrial interest using DPPH, ABTS, FRAP, SOD, and ORAC assays.

PubMed

Dudonné, Stéphanie; Vitrac, Xavier; Coutière, Philippe; Woillez, Marion; Mérillon, Jean-Michel

2009-03-11

Aqueous extracts of 30 plants were investigated for their antioxidant properties using DPPH and ABTS radical scavenging capacity assay, oxygen radical absorbance capacity (ORAC) assay, superoxide dismutase (SOD) assay, and ferric reducing antioxidant potential (FRAP) assay. Total phenolic content was also determined by the Folin-Ciocalteu method. Antioxidant properties and total phenolic content differed significantly among selected plants. It was found that oak (Quercus robur), pine (Pinus maritima), and cinnamon (Cinnamomum zeylanicum) aqueous extracts possessed the highest antioxidant capacities in most of the methods used, and thus could be potential rich sources of natural antioxidants. These extracts presented the highest phenolic content (300-400 mg GAE/g). Mate (Ilex paraguariensis) and clove (Eugenia caryophyllus clovis) aqueous extracts also showed strong antioxidant properties and a high phenolic content (about 200 mg GAE/g). A significant relationship between antioxidant capacity and total phenolic content was found, indicating that phenolic compounds are the major contributors to the antioxidant properties of these plants.

Contributions of phenolics and added vitamin C to the antioxidant capacity of pomegranate and grape juices: synergism and antagonism among constituents†

PubMed Central

Bolling, Bradley W.; Chen, Ya-Yen; Chen, C-Y. Oliver

2013-01-01

The aim of this study was to examine the contribution of sugar, organic acid, neutral phenol, and anthocyanin fractions and added ascorbic acid to grape and pomegranate-nectarine juice total phenol, ORAC, FRAP, and DPPH values. Neutral phenol and anthocyanin fractions contributed ≥75% of the total antioxidant capacity (TAC) for both juices. Intrinsic synergy and antagonism among the fractionated constituents occurred inconsistently in each assay. Sugars and organic acids antagonized pomegranate juice neutral phenols and anthocyanins in the DPPH assay by 50% and the grape juice ORAC value by 21%, but were synergistic to the grape juice FRAP value. The added ascorbic acid was dose-dependently synergistic with pomegranate and grape juice total phenol, DPPH, and FRAP assays, but less so in the ORAC assay. Thus, the interactions between grape and pomegranate juice constituents determine TAC and total phenol values, and synergy in these assays could not be attributed solely to polyphenols. PMID:24187439

Effect of cultivar on phenolic levels, anthocyanin composition, and antioxidant properties in purple basil (Ocimum basilicum L.).

PubMed

Flanigan, Patrick M; Niemeyer, Emily D

2014-12-01

In this study, we determined the effect of cultivar on total and individual anthocyanin concentrations and phenolic acid levels in eight purple basil varieties and examined the relationship between anthocyanin content, phenolic acid composition, and antioxidant properties. Cultivar had a significant influence on total anthocyanin concentrations as well as individual anthocyanin composition. The four major basil anthocyanins (labelled A-D) were quantified and cultivar had a statistically significant effect on anthocyanins B (p<0.01), C (p<0.01), and D (p<0.01), but not on anthocyanin A (p=0.94). Cultivar did not have a significant effect on total phenolic levels, although it did influence the concentration of some individual phenolic acids, including caftaric (p=0.03) and chicoric (p=0.04) acids. Although total phenolic and anthocyanin levels correlated with measured FRAP antioxidant capacities, for some cultivars the individual phenolic acid and anthocyanin composition was also an important factor affecting the antioxidant properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

MICROBIAL METABOLISM OF AROMATIC COMPOUNDS I.

PubMed Central

Tabak, Henry H.; Chambers, Cecil W.; Kabler, Paul W.

1964-01-01

Tabak, Henry H. (Robert A. Taft Sanitary Engineering Center, Cincinnati, Ohio), Cecil W. Chambers, and Paul W. Kabler. Microbial metabolism of aromatic carbon compounds. I. Decomposition of phenolic compounds and aromatic hydrocarbons by phenol-adapted bacteria. J. Bacteriol. 87:910–919. 1964.—Bacteria from soil and related environments were selected or adapted to metabolize phenol, hydroxy phenols, nitrophenols, chlorophenols, methylphenols, alkylphenols, and arylphenols when cultured in mineral salts media with the specific substrate as the sole source of carbon. A phenol-adapted culture (substrate-induced enzyme synthesis proven) was challenged in respirometric tests with 104 related compounds; probable significant oxidative activity occurred with 65. Dihydric phenols were generally oxidized; trihydric phenols were not. Cresols and dimethylphenols were oxidized; adding a chloro group increased resistance. Benzoic and hydroxybenzoic acids were oxidized; sulfonated, methoxylated, nitro, and chlorobenzoic acids were not; m-toluic acid was utilized but not the o- and p-isomers. Benzaldehyde and p-hydroxybenzaldehyde were oxidized. In general, nitro- and chloro-substituted compounds and the benzenes were difficult to oxidize. PMID:14137630

Content of phenolic compounds and free polyamines in black chokeberry (Aronia melanocarpa) after application of polyamine biosynthesis regulators.

PubMed

Hudec, Jozef; Bakos, Dusan; Mravec, Dusan; Kobida, L'ubomír; Burdová, Maria; Turianica, Ivan; Hlusek, Jaroslav

2006-05-17

The total contents of anthocyanins, flavonoids, and phenolics in 60 samples of black chokeberries (Aronia melanocarpa), after treating with catabolites of polyamine biosynthesis (KPAb) and ornithine decarboxylase inhibitor, were analyzed spectrophotometrically, and quercetin and free polyamine contents were analyzed by RP-HPLC with UV detection. The average total contents of the individual substances and phenolic subgroups in control berries were as follows (mg x kg(-1)): anthocyanines, 6408; flavonoids, 664; phenolics, 37,600; quercetin, 349. KPAb decreased total contents of anthocyanines and phenolics only slightly but significantly increased the content of flavonoids. This caused an important change in the abundance of flavonoids in the pigment complex. The absolute content of quercetin was increased, but its ratio to flavonoids content was decreased. Ornithine decarboxylase inhibitor had a markedly different effect as it significantly increased total content of anthocyanins and total phenolics, inhibited the total content of free polyamines, and stimulated the processes of saccharides transformation to phenolic pigments.

[Kinetics of catalytic wet air oxidation of phenol in trickle bed reactor].

PubMed

Li, Guang-ming; Zhao, Jian-fu; Wang, Hua; Zhao, Xiu-hua; Zhou, Yang-yuan

2004-05-01

By using a trickle bed reactor which was designed by the authors, the catalytic wet air oxidation reaction of phenol on CuO/gamma-Al2O3 catalyst was studied. The results showed that in mild operation conditions (at temperature of 180 degrees C, pressure of 3 MPa, liquid feed rate of 1.668 L x h(-1) and oxygen feed rate of 160 L x h(-1)), the removal of phenol can be over 90%. The curve of phenol conversion is similar to "S" like autocatalytic reaction, and is accordance with chain reaction of free radical. The kinetic model of pseudo homogenous reactor fits the catalytic wet air oxidation reaction of phenol. The effects of initial concentration of phenol, liquid feed rate and temperature for reaction also were investigated.

Total Phenolics and Total Flavonoids in Selected Indian Medicinal Plants

PubMed Central

Sulaiman, C. T.; Balachandran, Indira

2012-01-01

Plant phenolics and flavonoids have a powerful biological activity, which outlines the necessity of their determination. The phenolics and flavonoids content of 20 medicinal plants were determined in the present investigation. The phenolic content was determined by using Folin-Ciocalteu assay. The total flavonoids were measured spectrophotometrically by using the aluminium chloride colorimetric assay. The results showed that the family Mimosaceae is the richest source of phenolics, (Acacia nilotica: 80.63 mg gallic acid equivalents, Acacia catechu 78.12 mg gallic acid equivalents, Albizia lebbeck 66.23 mg gallic acid equivalents). The highest total flavonoid content was revealed in Senna tora which belongs to the family Caesalpiniaceae. The present study also shows the ratio of flavonoids to the phenolics in each sample for their specificity. PMID:23439764

Analytical Determinations of the Phenolic Content of Dissolved Organic Matter

NASA Astrophysics Data System (ADS)

Pagano, T.; Kenny, J. E.

2010-12-01

Indicators suggest that the amount of dissolved organic matter (DOM) in natural waters is increasing. Climate Change has been proposed as a potential contributor to the trend, and under this mechanism, the phenolic content of DOM may also be increasing. We have explored the possibility of assessing the phenolic character of DOM using fluorescence spectroscopy as a more convenient alternative to wet chemistry methods. In this work, parallel factor analysis (PARAFAC) was applied to fluorescence excitation emission matrices (EEMs) of humic samples in an attempt to analyze their phenolic content. The PARAFAC results were correlated with phenol concentrations derived from the Folin-Ciocalteau reagent-based method. The reagent-based method showed that the phenolic content of five International Humic Substance Society (IHSS) DOM samples vary from approximately 5 to 22 ppm Tannic Acid Equivalents (TAE) in phenol concentration. A five-component PARAFAC fit was applied to the EEMs of the IHSS sample dataset and it was determined by PARAFAC score correlations with phenol concentrations from the reagent-based method that components C1 (R2=0.78), C4 (R2=0.82), and C5 (R2=0.88) have the highest probability of containing phenolic groups. Furthermore, when the scores of components C4 and C5 were summed, the correlation improved (R2=0.99). Likewise, when the scores of C1, C4, and C5 were summed, their correlations were stronger than their individual parts (R2=0.89). Since the reagent-based method is providing an indicator of “total phenol” amount, regardless of the exact molecular structure of C1, C4, and C5, it seems reasonable that each of these components individually contributes a portion to the summed “total phenol” profile, and that the sum of their phenol-related spectral parts represents a larger portion of the “total phenol” index. However, when the sum of all five components were plotted against the reagent-based phenol concentrations, due to the considerable impact of largely non-phenolic components C2 (R2=0.23) and C3 (R2=0.35), the correlation was quite poor (or no correlation at all with R2=0.10). The results show the potential for PARAFAC analysis of multidimensional fluorescence data to be a tool for monitoring the phenolic content of DOM. Applications include assessing the potential for formation of disinfection byproducts in the treatment of drinking water and monitoring the impact of Climate Change on the phenolic character of DOM.

Wettability of southern pine veneer by phenol formaldehyde wood adhesives

Treesearch

Chung-Yun Hse

1972-01-01

Wettability of southern pine veneers was judged by measuring the contact angles made by 36 phenol formaldehyde resins. Formulation of the resins was by factorial design, the molar ratios of sodium hydroxide to phenol being 0.4, 0.7, and 1.0, the levels of resin solids content in the reaction mixture 37, 40, and 43 percent, and the molar ratios of formaldehyde to phenol...

Wettability of southern pine veneer by phenol formaldehyde wood adhesives

Treesearch

C. -Y. Hse

1972-01-01

Wettabillty of southern pine veneers was judged by measuring the contact angles made by 36 phenol formaldehyde resins. Formulation of the resins was by factorial design. the molar ratios of sodium hydroxide to phenol being 0.4, 0.7, and 1.0, the levels of resin solids content in the reaction mixture 37, 40, and 43 percent, and the molar ratios of formaldehyde to phenol...

40 CFR Table 2 to Subpart Ooo of... - Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins

Code of Federal Regulations, 2011 CFR

2011-07-01

... (HAP) From the Manufacture of Amino/Phenolic Resins 2 Table 2 to Subpart OOO of Part 63 Protection of... Pollutant Emissions: Manufacture of Amino/Phenolic Resins Pt. 63, Subpt. OOO, Table 2 Table 2 to Subpart OOO of Part 63—Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins...

40 CFR Table 2 to Subpart Ooo of... - Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins

Code of Federal Regulations, 2010 CFR

2010-07-01

... (HAP) From the Manufacture of Amino/Phenolic Resins 2 Table 2 to Subpart OOO of Part 63 Protection of... Pollutant Emissions: Manufacture of Amino/Phenolic Resins Pt. 63, Subpt. OOO, Table 2 Table 2 to Subpart OOO of Part 63—Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins...

40 CFR 721.5560 - Formaldehyde, polymer with (chloromethyl) oxirane and phenol, reaction products with 6H-dibenz[c...

Code of Federal Regulations, 2011 CFR

2011-07-01

... (chloromethyl) oxirane and phenol, reaction products with 6H-dibenz[c,e][1,2]oxaphosphorin-6-oxide. 721.5560... Substances § 721.5560 Formaldehyde, polymer with (chloromethyl) oxirane and phenol, reaction products with 6H... phenol, reaction products with 6H-dibenz[c,e][1,2]oxaphosphorin-6-oxide. (PMN P-00-991; CAS No. 300371-38...

40 CFR 721.5560 - Formaldehyde, polymer with (chloromethyl) oxirane and phenol, reaction products with 6H-dibenz[c...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (chloromethyl) oxirane and phenol, reaction products with 6H-dibenz[c,e][1,2]oxaphosphorin-6-oxide. 721.5560... Substances § 721.5560 Formaldehyde, polymer with (chloromethyl) oxirane and phenol, reaction products with 6H... phenol, reaction products with 6H-dibenz[c,e][1,2]oxaphosphorin-6-oxide. (PMN P-00-991; CAS No. 300371-38...

PHENOLIC ACIDS AND LIGNINS IN THE LYCOPODIALES,

DTIC Science & Technology

ethanolysis or alkaline oxidation of their extracted wood-meals. p-Hydroxybenzoic, vanillic, p-coumaric and ferulic acids were identified in phenolic acid ...Twenty-one species and varieties of Lycopodium have been examined for phenolic acids and for phenolic aldehydes, ketones and acids obtained on...found to yield syringic acid in the ethanol-soluble fraction and on degradation of lignin whereas species included in the genera Huperzia and Lepidotis

Quantitative and Qualitative Analysis of Phenolic and Flavonoid Content in Moringa oleifera Lam and Ocimum tenuiflorum L.

PubMed Central

Sankhalkar, Sangeeta; Vernekar, Vrunda

2016-01-01

Background: Number of secondary compounds is produced by plants as natural antioxidants. Moringa oleifera Lam. and Ocimum tenuiflorum L. are known for their wide applications in food and pharmaceutical industry. Objective: To compare phenolic and flavonoid content in M. oleifera Lam and O. tenuiflorum L. by quantitative and qualitative analysis. Materials and Methods: Phenolic and flavonoid content were studied spectrophotometrically and by paper chromatography in M. oleifera Lam. and O. tenuiflorum L. Results: Higher phenolic and flavonoid content were observed in Moringa leaf and flower. Ocimum flower showed higher phenolic content and low flavonoid in comparison to Moringa. Flavonoids such as biflavonyl, flavones, glycosylflavones, and kaempferol were identified by paper chromatography. Phytochemical analysis for flavonoid, tannins, saponins, alkaloids, reducing sugars, and anthraquinones were tested positive for Moringa and Ocimum leaf as well as flower. Conclusions: In the present study higher phenolic and flavonoid content, indicated the natural antioxidant nature of Moringa and Ocimum signifying their medicinal importance. SUMMARY Moringa oleifera Lam. and Ocimum tenuiflorum L. are widly grown in India and are known for their medicinal properties. Number of secondary metabolites like phenolics and flavonoids are known to be present in both the plants. The present study was conducted with an objective to qualitatively and quantitatively compare the phenolics and flavanoids in these two medicinally important plants.Quantitation of total phenolics and flavanoids was done by spectrophotometrically while qualitative analysis was perfomed by paper chromatography and by phytochemical tests. Our results have shown higher phenolics and flavanoid content in Moringa leaf and flower. However, higher phenolic content was absent in Ocimum flower compared to that of Moringa. Phytochemical analysis of various metabolites such as flavonoids, tanins, sapponins, alkaloids, anthraquinones revealed that both the plant extracts were rich sources of secondary metabolites and thus tested positive for the above tests. Various flavanoids and Phenolics were identified by paper chromatography based on their Rf values and significant colors. From the above study we conclude that Moringa and Ocimum are rich in natural antioxidants hence are potent source in pharmaceutical industry. PMID:26941531

Use of Field-Based Stable Isotope Probing To Identify Adapted Populations and Track Carbon Flow through a Phenol-Degrading Soil Microbial Community

PubMed Central

DeRito, Christopher M.; Pumphrey, Graham M.; Madsen, Eugene L.

2005-01-01

The goal of this field study was to provide insight into three distinct populations of microorganisms involved in in situ metabolism of phenol. Our approach measured 13CO2 respired from [13C]phenol and stable isotope probing (SIP) of soil DNA at an agricultural field site. Traditionally, SIP-based investigations have been subject to the uncertainties posed by carbon cross-feeding. By altering our field-based, substrate-dosing methodologies, experiments were designed to look beyond primary degraders to detect trophically related populations in the food chain. Using gas chromatography-mass spectrometry (GC/MS), it was shown that 13C-labeled biomass, derived from primary phenol degraders in soil, was a suitable growth substrate for other members of the soil microbial community. Next, three dosing regimes were designed to examine active members of the microbial community involved in phenol metabolism in situ: (i) 1 dose of [13C]phenol, (ii) 11 daily doses of unlabeled phenol followed by 1 dose of [13C]phenol, and (iii) 12 daily doses of [13C]phenol. GC/MS analysis demonstrated that prior exposure to phenol boosted 13CO2 evolution by a factor of 10. Furthermore, imaging of 13C-treated soil using secondary ion mass spectrometry (SIMS) verified that individual bacteria incorporated 13C into their biomass. PCR amplification and 16S rRNA gene sequencing of 13C-labeled soil DNA from the 3 dosing regimes revealed three distinct clone libraries: (i) unenriched, primary phenol degraders were most diverse, consisting of α-, β-, and γ-proteobacteria and high-G+C-content gram-positive bacteria, (ii) enriched primary phenol degraders were dominated by members of the genera Kocuria and Staphylococcus, and (iii) trophically related (carbon cross-feeders) were dominated by members of the genus Pseudomonas. These data show that SIP has the potential to document population shifts caused by substrate preexposure and to follow the flow of carbon through terrestrial microbial food chains. PMID:16332760

Quantitative and Qualitative Analysis of Phenolic and Flavonoid Content in Moringa oleifera Lam and Ocimum tenuiflorum L.

PubMed

Sankhalkar, Sangeeta; Vernekar, Vrunda

2016-01-01

Number of secondary compounds is produced by plants as natural antioxidants. Moringa oleifera Lam. and Ocimum tenuiflorum L. are known for their wide applications in food and pharmaceutical industry. To compare phenolic and flavonoid content in M. oleifera Lam and O. tenuiflorum L. by quantitative and qualitative analysis. Phenolic and flavonoid content were studied spectrophotometrically and by paper chromatography in M. oleifera Lam. and O. tenuiflorum L. Higher phenolic and flavonoid content were observed in Moringa leaf and flower. Ocimum flower showed higher phenolic content and low flavonoid in comparison to Moringa. Flavonoids such as biflavonyl, flavones, glycosylflavones, and kaempferol were identified by paper chromatography. Phytochemical analysis for flavonoid, tannins, saponins, alkaloids, reducing sugars, and anthraquinones were tested positive for Moringa and Ocimum leaf as well as flower. In the present study higher phenolic and flavonoid content, indicated the natural antioxidant nature of Moringa and Ocimum signifying their medicinal importance. Moringa oleifera Lam. and Ocimum tenuiflorum L. are widly grown in India and are known for their medicinal properties. Number of secondary metabolites like phenolics and flavonoids are known to be present in both the plants. The present study was conducted with an objective to qualitatively and quantitatively compare the phenolics and flavanoids in these two medicinally important plants.Quantitation of total phenolics and flavanoids was done by spectrophotometrically while qualitative analysis was perfomed by paper chromatography and by phytochemical tests. Our results have shown higher phenolics and flavanoid content in Moringa leaf and flower. However, higher phenolic content was absent in Ocimum flower compared to that of Moringa. Phytochemical analysis of various metabolites such as flavonoids, tanins, sapponins, alkaloids, anthraquinones revealed that both the plant extracts were rich sources of secondary metabolites and thus tested positive for the above tests. Various flavanoids and Phenolics were identified by paper chromatography based on their Rf values and significant colors. From the above study we conclude that Moringa and Ocimum are rich in natural antioxidants hence are potent source in pharmaceutical industry.

Campho-Phenique overdose

MedlinePlus

Campho-Phenique contains both camphor and phenol. For information on products containing camphor alone, see camphor overdose . ... Both camphor and phenol are in Campho-Phenique. However, camphor and phenol may be found separately in other products.

Relationship between red wine grades and phenolics. 1. Tannin and total phenolics concentrations.

PubMed

Mercurio, Meagan D; Dambergs, Robert G; Cozzolino, Daniel; Herderich, Markus J; Smith, Paul A

2010-12-08

Measuring chemical composition is a common approach to support decisions about allocating foods and beverages to grades related to market value. Red wine is a particularly complex beverage, and multiple compositional attributes are needed to account for its sensory properties, including measurement of key phenolic components such as anthocyanins, total phenolics, and tannin, which are related to color and astringency. Color has been shown to relate positively to red wine grade; however, little research has been presented that explores the relationship between astringency-related components such as total phenolic or tannin concentration and wine grade. The aim of this research has been to investigate the relationship between the wine grade allocations of commercial wineries and total phenolic and tannin concentrations, respectively, in Australian Shiraz and Cabernet Sauvignon wines. Total phenolic and tannin concentrations were determined using the methyl cellulose precipitable (MCP) tannin assay and then compared to wine grade allocations made by winemaker panels during the companies' postvintage allocation process. Data were collected from wines produced by one Australian wine company over the 2005, 2006, and 2007 vintages and by a further two companies in 2007 (total wines = 1643). Statistical analysis revealed a positive trend toward higher wine grade allocation and wines that had higher concentrations of both total phenolics and tannin, respectively. This research demonstrates that for these companies, in general, Cabernet Sauvignon and Shiraz wines allocated to higher market value grades have higher total phenolics and higher tannin concentrations and suggests that these compositional parameters should be considered in the development of future multiparameter decision support systems for relevant commercial red wine grading processes. In addition, both tannin and total phenolics would ideally be included because although, in general, a positive relationship exists between the two parameters, this relationship does not hold for all wine styles.

Degradation of Malaysian peatlands decreases levels of phenolics in soil and in leaves of Macaranga pruinosa

NASA Astrophysics Data System (ADS)

Yule, Catherine; Lim, Yau; Lim, Tse

2016-04-01

Indo-Malaysian tropical peat swamp forests (PSF) sequester enormous stores of carbon in the form of phenolic compounds, particularly lignin as well as tannins. These phenolic compounds are crucial for ecosystem functioning in PSF through their inter-related roles in peat formation and plant defenses. Disturbance of PSF causes destruction of the peat substrate, but the specific impact of disturbance on phenolic compounds in peat and its associated vegetation has not previously been examined. A scale was developed to score peatland degradation based on the three major human impacts that affect tropical PSF - logging, drainage and fire. The objectives of this study were to compare the amount of phenolic compounds in Macaranga pruinosa, a common PSF tree, and in the peat substrate along a gradient of peatland degradation from pristine peat swamp forest to cleared, drained and burnt peatlands. We examined phenolic compounds in M. pruinosa and in peat and found that levels of total phenolic compounds and total tannins decrease in the leaves of M.pruinosa and also in the surface peat layers with an increase in peatland degradation. We conclude that waterlogged conditions preserve the concentration of phenolic compounds in peat, and that even PSF that has been previously logged but which has recovered a full canopy cover will have high levels of total phenolic content (TPC) in peat. High levels of TPC in peat and in the flora are vital for the inhibition of decomposition of organic matter and this is crucial for the accretion of peat and the sequestration of carbon. Thus regional PSF flourish despite the phenolic rich, toxic, waterlogged, nutrient poor, conditions, and reversal of such conditions is a sign of degradation.

Comparative phenolic compound profiles and antioxidative activity of the fruit, leaves, and roots of Korean ginseng (Panax ginseng Meyer) according to cultivation years

PubMed Central

Chung, Ill-Min; Lim, Ju-Jin; Ahn, Mun-Seob; Jeong, Haet-Nim; An, Tae-Jin; Kim, Seung-Hyun

2015-01-01

Background The study of phenolic compounds profiles and antioxidative activity in ginseng fruit, leaves, and roots with respect to cultivation years, and has been little reported to date. Hence, this study examined the phenolic compounds profiles and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activities in the fruit, leaves, and roots of Korean ginseng (Panax ginseng Meyer) as a function of cultivation year. Methods Profiling of 23 phenolic compounds in ginseng fruit, leaves, and roots was investigated using ultra-high performance liquid chromatography with the external calibration method. Antioxidative activity of ginseng fruit, leaves, and roots were evaluated using the method of DPPH free-radical-scavenging activity. Results The total phenol content in ginseng fruit and leaves was higher than in ginseng roots (p < 0.05), and the phenol content in the ginseng samples was significantly correlated to the DPPH free-radical-scavenging activity (r = 0.928****). In particular, p-coumaric acid (r = 0.847****) and ferulic acid (r = 0.742****) greatly affected the DPPH activity. Among the 23 phenolic compounds studied, phenolic acids were more abundant in ginseng fruit, leaves, and roots than the flavonoids and other compounds (p < 0.05). In particular, chlorogenic acid, gentisic acid, p- and m-coumaric acid, and rutin were the major phenolic compounds in 3–6-yr-old ginseng fruit, leaves, and roots. Conclusion This study provides basic information about the antioxidative activity and phenolic compounds profiles in fruit, leaves, and roots of Korean ginseng with cultivation years. This information is potentially useful to ginseng growers and industries involved in the production of high-quality and nutritional ginseng products. PMID:26843824

Effect of Maturity on Phenolics (Phenolic Acids and Flavonoids) Profile of Strawberry Cultivars and Mulberry Species from Pakistan

PubMed Central

Mahmood, Tahir; Anwar, Farooq; Abbas, Mateen; Saari, Nazamid

2012-01-01

In this study, we investigated how the extent of ripeness affects the yield of extract, total phenolics, total flavonoids, individual flavonols and phenolic acids in strawberry and mulberry cultivars from Pakistan. In strawberry, the yield of extract (%), total phenolics (TPC) and total flavonoids (TFC) ranged from 8.5–53.3%, 491–1884 mg gallic acid equivalents (GAE)/100 g DW and 83–327 mg catechin equivalents (CE)/100 g DW, respectively. For the different species of mulberry the yield of extract (%), total phenolics and total flavonoids of 6.9–54.0%, 201–2287 mg GAE/100 g DW and 110–1021 mg CE/100 g DW, respectively, varied significantly as fruit maturity progressed. The amounts of individual flavonols and phenolic acid in selected berry fruits were analyzed by RP-HPLC. Among the flavonols, the content of myricetin was found to be high in Morus alba (88 mg/100 g DW), the amount of quercetin as high in Morus laevigata (145 mg/100 g DW) while kaempferol was highest in the Korona strawberry (98 mg/100 g DW) at fully ripened stage. Of the six phenolic acids detected, p-hydroxybenzoic and p-coumaric acid were the major compounds in the strawberry. M. laevigata and M. nigra contained p-coumaric acid and vanillic acid while M. macroura and M. alba contained p-hydroxy-benzoic acid and chlorogenic acid as the major phenolic acids. Overall, a trend to an increase in the percentage of extraction yield, TPC, TFC, flavonols and phenolic acids was observed as maturity progressed from un-ripened to fully-ripened stages. PMID:22605997

Laccase enzyme detoxifies hydrolysates and improves biogas production from hemp straw and miscanthus.

PubMed

Schroyen, Michel; Van Hulle, Stijn W H; Holemans, Sander; Vervaeren, Han; Raes, Katleen

2017-11-01

The impact of various phenolic compounds, vanillic acid, ferulic acid, p-coumaric acid and 4-hydroxybenzoic acid on anaerobic digestion of lignocellulosic biomass (hemp straw and miscanthus) was studied. Such phenolic compounds have been known to inhibit biogas production during anaerobic digestion. The different phenolic compounds were added in various concentrations: 0, 100, 500, 1000 and 2000mg/L. A difference in inhibition of biomethane production between the phenolic compounds was noted. Hydrolysis rate, during anaerobic digestion of miscanthus was inhibited up to 50% by vanillic acid, while vanillic acid had no influence on the initial rate of biogas production during the anaerobic digestion of hemp straw. Miscanthus has a higher lignin concentration (12-30g/100gDM) making it less accessible for degradation, and in combination with phenolic compounds released after harsh pretreatments, it can cause severe inhibition levels during the anaerobic digestion, lowering biogas production. To counter the inhibition, lignin degrading enzymes can be used to remove or degrade the inhibitory phenolic compounds. The interaction of laccase and versatile peroxidase individually with the different phenolic compounds was studied to have insight in the polymerization of inhibitory compounds or breakdown of lignocellulose. Hemp straw and miscanthus were incubated with 0, 100 and 500mg/L of the different phenolic compounds for 0, 6 and 24h and pretreated with the lignin degrading enzymes. A laccase pretreatment successfully detoxified the substrate, while versatile peroxidase however was inhibited by 100mg/L of each of the individual phenolic compounds. Finally a combination of enzymatic detoxification and subsequent biogas production showed that a decrease in phenolic compounds by laccase treatment can considerably lower the inhibition levels of the biogas production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Forest Gaps Alter the Total Phenol Dynamics in Decomposing Litter in an Alpine Fir Forest

PubMed Central

Li, Han; Xu, Liya; Wu, Fuzhong; Yang, Wanqin; Ni, Xiangyin; He, Jie; Tan, Bo; Hu, Yi

2016-01-01

The total phenol content in decomposing litter not only acts as a crucial litter quality indicator, but is also closely related to litter humification due to its tight absorption to clay particles. However, limited attention has been focused on the total phenol dynamics in foliar litter in relation to forest gaps. Here, the foliar litter of six representative tree species was incubated on the forest floor from the gap center to the closed canopy of an alpine Minjiang fir (Abies faxoniana) forest in the upper reaches of the Yangtze River and eastern Tibetan Plateau. The dynamics of total phenol concentration in the incubated litter was measured from November 2012 to October 2014. Over two-year incubation, 78.22% to 94.06% of total phenols were lost from the foliar litter, but 52.08% to 86.41% of this occurred in the first year. Forest gaps accelerated the loss of total phenols in the foliar litter in the winter, although they inhibited the loss of total phenols during the growing season in the first year. In comparison with the effects of forest gaps, the variations of litter quality among different species were much stronger on the dynamics of total phenols in the second year. Overall, the loss of total phenols in the foliar litter was slightly higher in both the canopy gap and the expanded gap than in the gap center and under the closed canopy. The results suggest that the predicted decline in snow cover resulting from winter warming or vanishing gaps caused by forest regeneration will retard the loss of total phenol content in the foliar litter of alpine forest ecosystems, especially in the first decomposition year. PMID:26849120

Metabolism of phenol and hydroquinone to reactive products by macrophage peroxidase or purified prostaglandin H synthase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlosser, M.J.; Shurina, R.D.; Kalf, G.F.

1989-07-01

Macrophages, an important cell-type of the bone marrow stroma, are possible targets of benzene toxicity because they contain relatively large amounts of prostaglandin H synthase (PHS), which is capable of metabolizing phenolic compounds to reactive species. PHS also catalyzes the production of prostaglandins, negative regulators of myelopoiesis. Studies indicate that the phenolic metabolites of benzene are oxidized in bone marrow to reactive products via peroxidases. With respect to macrophages, PHS peroxidase is implicated, as in vivo benzene-induced myelotoxicity is prevented by low doses of nonsteroidal anti-inflammatory agents, drugs that inhibit PHS. Incubations of either 14C-phenol or 14C-hydroquinone with a lysatemore » of macrophages collected from mouse peritoneum (greater than 95% macrophages), resulted in an irreversible binding to protein that was dependent upon H2O2, incubation time, and concentration of radiolabel. Production of protein-bound metabolites from phenol or hydroquinone was inhibited by the peroxidase inhibitor aminotriazole. Protein binding from 14C-phenol also was inhibited by 8 microM hydroquinone, whereas binding from 14C-hydroquinone was stimulated by 5 mM phenol. The nucleophile cysteine inhibited protein binding of both phenol and hydroquinone and increased the formation of radiolabeled water-soluble metabolites. Similar to the macrophage lysate, purified PHS also catalyzed the conversion of phenol to metabolites that bound to protein and DNA; this activation was both H2O2- and arachidonic acid-dependent. These results indicate a role for macrophage peroxidase, possibly PHS peroxidase, in the conversion of phenol and hydroquinone to reactive metabolites and suggest that the macrophage should be considered when assessing the hematopoietic toxicity of benzene.« less

Evolution of the localisation and composition of phenolics in grape skin between veraison and maturity in relation to water availability and some climatic conditions.

PubMed

Cadot, Yves; Chevalier, Michel; Barbeau, Gerard

2011-08-30

Several studies have investigated the composition of phenolics in grape skin during grape maturation under various conditions of light exposure, water stress, nitrogen supply and mineral nutrition, but their localisation during berry development is not well known. In this study the composition and localisation of proanthocyanidins were monitored for three years on four plots known to induce a distinctive behaviour of the vine (Cabernet Franc). The composition of phenolics was determined by spectrophotometry; also, in one year, proanthocyanidins were determined by high-performance liquid chromatography. Further information was obtained histochemically by means of toluidine blue O staining and image analysis. The results indicated that clear differences in phenolic quantification existed between the biochemical and histochemical approaches; the proportion of cells without phenolics was not linked with the quantity determined by the analytical methods used. The histochemical method showed the evolution of the localisation and typology of cells with and without phenolics during ripening. The number of cells without any phenolic compounds appeared to be very dependent on the mesoclimatic conditions and only slightly dependent on the site water status. Clear differences in phenolic quantification existed between the biochemical and histochemical approaches; the proportion of cells with phenolics was not linked with the quantity determined by biochemistry. The histochemical method showed an evolution of the localisation and typology of cells with and without phenolics in which mesoclimatic conditions were the most influential factor. Finally, the study showed some advantages of the histochemical approach: it gives information about the anatomy of the tissue as well as the nature and distribution of some of the large macromolecules and allows reconstruction of the three-dimensional plant structure. Copyright © 2011 Society of Chemical Industry.

White wine taste and mouthfeel as affected by juice extraction and processing.

PubMed

Gawel, Richard; Day, Martin; Van Sluyter, Steven C; Holt, Helen; Waters, Elizabeth J; Smith, Paul A

2014-10-15

The juice used to make white wine can be extracted using various physical processes that affect the amount and timing of contact of juice with skins. The influence of juice extraction processes on the mouthfeel and taste of white wine and their relationship to wine composition were determined. The amount and type of interaction of juice with skins affected both wine total phenolic concentration and phenolic composition. Wine pH strongly influenced perceived viscosity, astringency/drying, and acidity. Despite a 5-fold variation in total phenolics among wines, differences in bitter taste were small. Perceived viscosity was associated with higher phenolics but was not associated with either glycerol or polysaccharide concentration. Bitterness may be reduced by using juice extraction and handling processes that minimize phenolic concentration, but lowering phenolic concentration may also result in wines of lower perceived viscosity.

Phenolic content and antioxidant capacity in algal food products.

PubMed

Machu, Ludmila; Misurcova, Ladislava; Ambrozova, Jarmila Vavra; Orsavova, Jana; Mlcek, Jiri; Sochor, Jiri; Jurikova, Tunde

2015-01-12

The study objective was to investigate total phenolic content using Folin-Ciocalteu's method, to assess nine phenols by HPLC, to determine antioxidant capacity of the water soluble compounds (ACW) by a photochemiluminescence method, and to calculate the correlation coefficients in commercial algal food products from brown (Laminaria japonica, Eisenia bicyclis, Hizikia fusiformis, Undaria pinnatifida) and red (Porphyra tenera, Palmaria palmata) seaweed, green freshwater algae (Chlorella pyrenoidosa), and cyanobacteria (Spirulina platensis). HPLC analysis showed that the most abundant phenolic compound was epicatechin. From spectrophotometry and ACW determination it was evident that brown seaweed Eisenia bicyclis was the sample with the highest phenolic and ACW values (193 mg·g-1 GAE; 7.53 µmol AA·g-1, respectively). A linear relationship existed between ACW and phenolic contents (r = 0.99). Some algal products seem to be promising functional foods rich in polyphenols.

Extracts of Phenolic Compounds from Seeds of Three Wild Grapevines—Comparison of Their Antioxidant Activities and the Content of Phenolic Compounds

PubMed Central

Weidner, Stanisław; Powałka, Anna; Karamać, Magdalena; Amarowicz, Ryszard

2012-01-01

Phenolic compounds were extracted from three wild grapevine species: Vitis californica, V. riparia and V. amurensis seeds using 80% methanol or 80% acetone. The total content of phenolic compounds was determined utilizing the Folin-Ciocalteu’s phenol reagent while the content of tannins was assayed with the vanillin and BSA precipitation methods. Additionally, the DPPH free radical scavenging activity and the reduction power of the extracts were measured. The RP-HPLC method was applied to identify the phenolic compounds in the extracts, such as phenolic acids and catechins. The seeds contained large amounts of tannins, catechins and gallic acid and observable quantities of p-coumaric acid. The total content of phenolic compounds and tannins was similar in the extracts from V. californica and V. riparia seeds. However, the total content of total phenolic compounds and tannins in the extracts from V. californica and V. riperia seeds were about two-fold higher than that in the extracts from V. amurensis seeds. Extracts from seeds of the American species (V. californica and V. riparia) contained similarly high concentrations of tannins, whereas extracts from seeds of V. amurensis had approximately half that amount of these compounds. The content of catechin and epicatechin was similar in all extracts. The highest DPPH• anti-radical scavenging activity was observed in the acetonic and methanolic extracts of V. californica and V. riparia seeds— while the acetonic extract from the V. californica seeds was the strongest reducing agent. PMID:22489161

Antineurodegenerative effect of phenolic extracts and caffeic acid derivatives in romaine lettuce on neuron-like PC-12 cells.

PubMed

Im, Sung-Eun; Yoon, Hyungeun; Nam, Tae-Gyu; Heo, Ho Jin; Lee, Chang Yong; Kim, Dae-Ok

2010-08-01

In recent decades, romaine lettuce has been one of the fastest growing vegetables with respect to its consumption and production. An understanding is needed of the effect of major phenolic phytochemicals from romaine lettuce on biological protection for neuron-like PC-12 cells. Phenolics in fresh romaine lettuce were extracted, and then its total phenolics and total antioxidant capacity were measured spectrophotometrically. Neuroprotective effects of phenolic extract of romaine lettuce and its pure caffeic acid derivatives (caffeic, chicoric, chlorogenic, and isochlorogenic acids) in PC-12 cells were evaluated using two different in vitro methods: lactate dehydrogenase release and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assays. Total phenolics and total antioxidant capacity of 100 g of fresh romaine lettuce averaged 22.7 mg of gallic acid equivalents and 31.0 mg of vitamin C equivalents, respectively. The phenolic extract of romaine lettuce protected PC-12 cells against oxidative stress caused by H(2)O(2) in a dose-dependent manner. Isochlorogenic acid, one of the phenolics in romaine lettuce, showed stronger neuroprotection than the other three caffeic acid derivatives also found in the lettuce. Although romaine lettuce had lower levels of phenolics and antioxidant capacity compared to other common vegetables, its contribution to total antioxidant capacity and antineurodegenerative effect in human diets would be higher because of higher amounts of its daily per capita consumption compared to other common vegetables.

Determination of Phenols Isomers in Water by Novel Nanosilica/Polydimethylsiloxane-Coated Stirring Bar Combined with High Performance Liquid Chromatography-Fourier Transform Infrared Spectroscopy.

PubMed

Zheng, Bei; Li, Wentao; Liu, Lin; Wang, Xin; Chen, Chen; Yu, Zhiyong; Li, Hongyan

2017-08-18

A novel nanosilica/polydimethylsiloxane (SiO 2 /PDMS) coated stirring bar was adopted in the sorption extraction (SBSE) of phenols in water, and the high performance liquid chromatography-fourier transform infrared spectroscopy (HPLC-FTIR) was subsequently used to determination of phenol concentration. The SiO 2 /PDMS coating was prepared by sol-gel method and characterized with respect to morphology and specific surface area. The results of field-emission scanning electron microscope (FE-SEM) and N 2 adsorption-desorption as well as phenol adsorption experiments denoted that SiO 2 /PDMS has larger surface area and better adsorption capacity than commercial PDMS. The extraction efficiency of phenol with SiO 2 /PDMS coated stirring bar was optimized in terms of ion strength, flow rate of phenol-involved influent, type of desorption solvent and desorption time. More than 75% of phenol desorption efficiency could be kept even after 50 cycles of extraction, indicating the high stability of the SiO 2 /PDMS coated stirring bar. Approximately 0.16 mg/L 2, 5-dimethylphenol (2, 5-DMP), which was 34-fold more toxic than phenol, was detected in water through HPLC-FTIR. However, 2, 5-DMP could be oxidized to 5-methy-2-hydroxy benzaldehyde after disinfection in drinking water treatment process. Therefore, the proposed method of SiO 2 /PDMS-SBSE-HPLC-FTIR is successfully applied in the analysis of phenols isomers in aqueous environment.

Evaluation of antioxidant activity of three common potato (Solanum tuberosum) cultivars in Iran

PubMed Central

Hesam, Faride; Balali, Gholam Reza; Tehrani, Reza Taheri

2012-01-01

Objectives: Potato (Solanum tuberosum L.), as a whole food, contains high levels of vitamins and important antioxidants including phenolic acids, carotenoids and flavonoids. The objective of this study was to determine the total phenolic content and antioxidant activities of three common potatoes (Solanum tuberosum) cultivars in Iran i.e., Savalan, Agria and Sante. Materials and Methods: Phenolic compound extraction of samples was done with methanol and total phenolic on the basis of folin-ciocalteu assay was estimated as 16.58 to 36.24 mg GAE/100g dry sample. The antioxidant activities of potato extracts on the basis of inhibition of linoleic acid peroxidation and DPPH assay were compared with a commercially available antioxidant, α -tocopherol. Results: Savalan had the highest phenolic content and the highest DPPH radical scavenging activity with EC50 value of 41.815±mg/ml (DB). Also Savalan had the best inhibitory action against linoleic acid oxidation at 94.10±1.89% at 50 mg/ml sample concentration. Methanolic potato extracts had better antioxidant activity than α-tocopherol. Significant (p<0.01) negative correlation was observed between total phenolic content and the EC50 for DPPH radical scavenging activity(R=-0.877), but there was no correlation between total phenolic content and total antioxidant activity. Conclusion: Metanolic extracts of three potato cultivars are able to inhibit the oxidation process. The correlation between total phenolic content and DPPH radical scavenging activity indicates that phenolic compounds are responsible for antiradical activity. PMID:25050234

Influence of rice straw polyphenols on cellulase production by Trichoderma reesei.

PubMed

Zheng, Wei; Zheng, Qin; Xue, Yiyun; Hu, Jiajun; Gao, Min-Tian

2017-06-01

In this study, we found that during cellulase production by Trichoderma reesei large amounts of polyphenols were released from rice straw when the latter was used as the carbon source. We identified and quantified the phenolic compounds in rice straw and investigated the effects of the phenolic compounds on cellulase production by T. reesei. The phenolic compounds of rice straw mainly consisted of phenolic acids and tannins. Coumaric acid (CA) and ferulic acid (FA) were the predominant phenolic acids, which inhibited cellulase production by T. reesei. When the concentrations of CA and FA in the broth increased to 0.06 g/L, cellulase activity decreased by 23% compared with that in the control culture. Even though the rice straw had a lower tannin than phenolic acid content, the tannins had a greater inhibitory effect than the phenolic acids on cellulase production by T. reesei. Tannin concentrations greater than 0.3 g/L completely inhibited cellulase production. Thus, phenolic compounds, especially tannins are the major inhibitors of cellulase production by T. reesei. Therefore, we studied the effects of pretreatments on the release of phenolic compounds. Ball milling played an important role in the release of FA and CA, and hot water extraction was highly efficient in removing tannins. By combining ball milling with extraction by water, the 2-fold higher cellulase activity than in the control culture was obtained. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Evaluation of Garlic Cultivars for Polyphenolic Content and Antioxidant Properties

PubMed Central

Cheng, Siqiong; Li, Panpan; Du, Junna; Chang, Yanxia; Meng, Huanwen

2013-01-01

Two phenolic compound parameters (total phenolic and flavonoid contents) and 5 antioxidant parameters (DPPH [2, 2-diphenyl-1-picrylhydrazyl] radical scavenging activity, HRSC (hydroxyl radical scavenging capacity), FRAP (ferric ion reducing antioxidant power), CUPRAC (cupric ion reducing antioxidant capacity), and MCA (metal chelating activity) were measured in bulbs and bolts of 43 garlic cultivars. The bulbs of cultivar ‘74-x’ had the highest phenolic content (total phenolic, flavonoids) and the strongest antioxidant capacity (DPPH, FRAP, and CUPRAC), followed by bulbs of cultivar ‘Hanzhong purple’; the bulbs of cultivar ‘Gailiang’ had the lowest phenolic content and antioxidant capacity (FRAP, CUPRAC, MCA). The bolts of ‘Hanzhong purple’ also had higher phenolic content. Principal components analysis (PCA) separated the cultivars into 3 groups according to phenolic and flavonoid contents and strength of antioxidant activity. The first group had higher HRSC, FRAP, and flavonoid content; the second group had higher total phenolic content and MCA; some cultivars in the third group had higher HRSC and FRAP. All 8 test garlic bulb extracts successfully prevented Human Vascular Endothelial Cell death and significantly prevented reactive-oxygen species (ROS) formation in oxidative stress model, in which cultivar ‘74-x’ had highest protection capability, following by cultivar ‘Hanzhong purple’, and the bulbs of cultivar ‘No. 105 from Korea’ had the lower protection capability against cell death and ROS formation. The protection capability in vivo of these garlic cultivars was consistent with their phenolic content and antioxidant capacity. PMID:24232741

Spectrophotometric Determination of Phenolic Antioxidants in the Presence of Thiols and Proteins

PubMed Central

Avan, Aslı Neslihan; Demirci Çekiç, Sema; Uzunboy, Seda; Apak, Reşat

2016-01-01

Development of easy, practical, and low-cost spectrophotometric methods is required for the selective determination of phenolic antioxidants in the presence of other similar substances. As electron transfer (ET)-based total antioxidant capacity (TAC) assays generally measure the reducing ability of antioxidant compounds, thiols and phenols cannot be differentiated since they are both responsive to the probe reagent. In this study, three of the most common TAC determination methods, namely cupric ion reducing antioxidant capacity (CUPRAC), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt/trolox equivalent antioxidant capacity (ABTS/TEAC), and ferric reducing antioxidant power (FRAP), were tested for the assay of phenolics in the presence of selected thiol and protein compounds. Although the FRAP method is almost non-responsive to thiol compounds individually, surprising overoxidations with large positive deviations from additivity were observed when using this method for (phenols + thiols) mixtures. Among the tested TAC methods, CUPRAC gave the most additive results for all studied (phenol + thiol) and (phenol + protein) mixtures with minimal relative error. As ABTS/TEAC and FRAP methods gave small and large deviations, respectively, from additivity of absorbances arising from these components in mixtures, mercury(II) compounds were added to stabilize the thiol components in the form of Hg(II)-thiol complexes so as to enable selective spectrophotometric determination of phenolic components. This error compensation was most efficient for the FRAP method in testing (thiols + phenols) mixtures. PMID:27529232

Influence of humic acids of different origins on oxidation of phenol and chlorophenols by permanganate.

PubMed

He, Di; Guan, Xiaohong; Ma, Jun; Yang, Xue; Cui, Chongwei

2010-10-15

The influences of humic acids (HAs) of different origins, including two commercial HAs, three soil HAs and one aquatic HA, on phenols oxidation by permanganate were studied. The apparent second-order rate constants of 2-chlorophenol (2-CP)/phenol oxidation by permanganate in the presence of HAs at pH 7 followed the order of commercial HA (Shanghai)>soil HAs>commercial HA (Fluka)>aquatic HA. Moreover, the commercial HA (Shanghai) could accelerate the oxidation of different chlorophenols (CP) significantly under neutral condition. The FTIR analysis demonstrated greater content of CC moieties and less amount of carboxylate, aliphatic groups and polysaccharide-like substances in soil HAs than in aqueous HA, suggesting that the increase of aromaticity in HA was beneficial to the oxidation of phenols by permanganate. The apparent second-order rate constants of 2-CP/phenol oxidation by permanganate in the presence of HAs correlated well with specific visible absorption (SVA) at 665 nm of HAs. High positive correlation coefficients (R(2)>0.75) implied that pi-electrons of HA strongly influenced the reactivity of 2-CP/phenol towards permanganate oxidation, which agreed well with positive correlation between Fluorescence Regional Integration (FRI) and the apparent second-order rate constants. The pi-pi interaction between HAs and phenols, the steric hindrance effect and the dissociation of phenols may affect the oxidation of phenols by permanganate in the presence of HA at pH=7.0. 2010 Elsevier B.V. All rights reserved.

Effect of Cooking on Isoflavones, Phenolic Acids, and Antioxidant Activity in Sprouts of Prosoy Soybean (Glycine max).

PubMed

Kumari, Shweta; Chang, Sam K C

2016-07-01

Soy sprouts possess health benefits and is required to be cooked before consumption. The effects of cooking on the phenolic components and antioxidant properties of soy sprouts with different germination days were investigated. A food-grade cultivar Prosoy with a high protein content was germinated for 1, 2, 3, 5, and 7 d and cooked till palatable for 20, 20, 5, 5, and 7 min, respectively. Total phenolic content (TPC), total flavonoids content (TFC), condensed tannins content (CTC), individual phenolic acids, isoflavones, DPPH, ferric-reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) of raw and cooked sprouts were measured. Cooking caused significant losses in phenolic content and antioxidant activities, and maximum loss was on day 3 > 5 > 7, including TPC (32%, 23%, and 15%), TFC (50%, 44%, and 20%), CTC (73%, 47%, and 12%), DPPH (31%, 15%, and 5%), FRAP (34%, 25%, and 1%), and ORAC (34%, 22%, 32%), respectively. Cooking caused significant losses in most individual phenolic acid, benzoic group, cinnamic group, total phenolic composition, individual isoflavones, and total isoflavones. The losses of phenolic acids such as gallic, protocatechuic, hydroxybenzoic, syringic, chlorogenic, or sinapic acids during cooking were not compensated by the increases in trihydroxybenzoic, vanillic or coumaric acids on certain days of germination. Cooking caused minimal changes in phenolic acid composition of day 1 and 2 sprouts compared to 3, 5, and 7 d sprouts. © 2016 Institute of Food Technologists®

Influences of harvest date and location on the levels of ß-carotene, ascorbic acid, total phenols, in vitro antioxidant capacity, and phenolic profiles of five commercial varieties of mango (Mangifera indica L.)

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in the peel, seeds, and leaves of mango, yet less is known about the phenolic ...

C-H functionalization of phenols using combined ruthenium and photoredox catalysis: in situ generation of the oxidant.

PubMed

Fabry, David C; Ronge, Meria A; Zoller, Jochen; Rueping, Magnus

2015-02-23

A combination of ruthenium and photoredox catalysis allowed the ortho olefination of phenols. Using visible light, the direct C-H functionalization of o-(2-pyridyl)phenols occurred, and diverse phenol ethers were obtained in good yields. The regeneration of the ruthenium catalyst was accomplished by a photoredox-catalyzed oxidative process. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Resole resin products derived from fractionated organic and aqueous condensates made by fast-pyrolysis of biomass materials

DOEpatents

Chum, Helena L.; Black, Stuart K.; Diebold, James P.; Kreibich, Roland E.

1993-01-01

A process for preparing phenol-formaldehyde resole resins by fractionating organic and aqueous condensates made by fast-pyrolysis of biomass materials while using a carrier gas to move feed into a reactor to produce phenolic-containing/neutrals in which portions of the phenol normally contained in said resins are replaced by a phenolic/neutral fractions extract obtained by fractionation.

Resole resin products derived from fractionated organic and aqueous condensates made by fast-pyrolysis of biomass materials

DOEpatents

Chum, H.L.; Black, S.K.; Diebold, J.P.; Kreibich, R.E.

1993-08-10

A process for preparing phenol-formaldehyde resole resins by fractionating organic and aqueous condensates made by fast-pyrolysis of biomass materials while using a carrier gas to move feed into a reactor to produce phenolic-containing/neutrals in which portions of the phenol normally contained in said resins are replaced by a phenolic/neutral fractions extract obtained by fractionation.

Development of Phenol-Enriched Olive Oil with Phenolic Compounds Extracted from Wastewater Produced by Physical Refining.

PubMed

Venturi, Francesca; Sanmartin, Chiara; Taglieri, Isabella; Nari, Anita; Andrich, Gianpaolo; Terzuoli, Erika; Donnini, Sandra; Nicolella, Cristiano; Zinnai, Angela

2017-08-22

While in the last few years the use of olive cake and mill wastewater as natural sources of phenolic compounds has been widely considered and several studies have focused on the development of new extraction methods and on the production of functional foods enriched with natural antioxidants, no data has been available on the production of a phenol-enriched refined olive oil with its own phenolic compounds extracted from wastewater produced during physical refining. In this study; we aimed to: (i) verify the effectiveness of a multi-step extraction process to recover the high-added-value phenolic compounds contained in wastewater derived from the preliminary washing degumming step of the physical refining of vegetal oils; (ii) evaluate their potential application for the stabilization of olive oil obtained with refined olive oils; and (iii) evaluate their antioxidant activity in an in vitro model of endothelial cells. The results obtained demonstrate the potential of using the refining wastewater as a source of bioactive compounds to improve the nutraceutical value as well as the antioxidant capacity of commercial olive oils. In the conditions adopted, the phenolic content significantly increased in the prototypes of phenol-enriched olive oils when compared with the control oil.

Rapid screening of low-molecular-weight phenols from persimmon (Diospyros kaki) pulp using liquid chromatography/UV-visible/electrospray mass spectrometry analysis.

PubMed

Sentandreu, Enrique; Cerdán-Calero, Manuela; Halket, John M; Navarro, José L

2015-06-01

Persimmon fruits have been widely used in traditional medicine owing to their phenolic composition. This research aims to perform a rapid, detailed and affordable study of the profile of low-molecular-weight phenols from persimmon pulp. Two different HPLC-DAD/ESI-MS(n) analyses were performed using a routine three-dimensional ion trap mass spectrometer to analyze the ethanolic extract of persimmon pulp: (1) an untargeted data-dependent analysis to identify the majority of small phenols that included full MS and MS(2) scan events; (2) a targeted data-dependent analysis to identify polymerized phenols (dimers and formic acid adducts) through a source-induced dissociation analysis that included full MS and MS(2) scan events. Thirty-two low-molecular-weight phenols were detected, comprising gallic acid and its glycoside and acyl derivatives, glycosides of p-coumaric, vanillic and cinnamic acids and different flavone di-C-hexosides, most of them reported for the first time in persimmon. The use of a straightforward and affordable methodology of analysis led to obtain an up-to-date profiling of low-molecular-weight phenols in persimmon. The results can help future actions aimed to expand the understanding of the phenolic metabolome of persimmon cultivars. © 2014 Society of Chemical Industry.

Phenolics, sugars, antimicrobial and free-radical-scavenging activities of Melicoccus bijugatus Jacq. fruits from the Dominican Republic and Florida.

PubMed

Bystrom, Laura M; Lewis, Betty A; Brown, Dan L; Rodriguez, Eloy; Obendorf, Ralph L

2009-06-01

Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses.

An Innovative Porous Nanocomposite Material for the Removal of Phenolic Compounds from Aqueous Solutions.

PubMed

Turco, Antonio; Monteduro, Anna Grazia; Mazzotta, Elisabetta; Maruccio, Giuseppe; Malitesta, Cosimino

2018-05-16

Energy efficient, low-cost, user-friendly, and green methods for the removal of toxic phenolic compounds from aqueous solution are necessary for waste treatment in industrial applications. Herein we present an interesting approach for the utilization of oxidized carbon nanotubes (CNTs) in the removal of phenolic compounds from aqueous solution. Dried pristine CNTs were stably incorporated in a solid porous support of polydimethylsiloxane (PDMS) facilitating the handling during both oxidation process of the nanomaterial and uptake of phenolic compounds, and enabling their safe disposal, avoiding expensive post-treatment processes. The adsorption studies indicated that the materials can efficiently remove phenolic compounds from water with different affinities towards different phenolic compounds. Furthermore, the adsorption kinetics and isotherms were studied in detail. The experimental data of adsorption fitted well with Langmuir and Freundlich isotherms, and pseudo-second-order kinetics, and the results indicated that the adsorption process was controlled by a two-step intraparticle diffusion model. The incorporation of CNTs in polymeric matrices did not affect their functionality in phenol uptake. The material was also successfully used for the removal of phenolic compounds from agricultural waste, suggesting its possible application in the treatment of wastewater. Moreover, the surface of the material could be regenerated, decreasing treatment costs.

Hydrothermal degradation of lignin: products analysis for phenol formaldehyde adhesive synthesis.

PubMed

Yang, Sheng; Yuan, Tong-Qi; Li, Ming-Fei; Sun, Run-Cang

2015-01-01

Corncob lignin was treated with pressurized hot water in a cylindrical autoclave in current investigation. With the aim of investigating the effect of reaction temperature and retention time on the distribution of degradation products, the products were divided into five fractions including gas, volatile organic compounds, water-soluble oil, heavy oil, and solid residue. It was found that hydrothermal degradation of corncob lignin in pressurized hot water produced a large amount of phenolic compounds with lower molecular weight than the raw lignin. Some phenolic and benzene derivatives monomers such as vanillin, 2-methoxy-phenol, 2-ethyl-phenol, p-xylene, and 1, 3-dimethyl-benzene were also identified in the degradation products. The products were further analyzed by GC-MS, GPC, 2D-HSQC, and (31)P-NMR to investigate their suitability for partial incorporation into phenol formaldehyde adhesive as a substitution of phenol. The results indicated that the reaction temperature had more effect on the products distribution than the retention time. The optimal condition for heavy oil production appeared at 290 °C with retention time 0 min. The compounds of heavy oil had more active sites than the raw lignin, suggesting that the heavy oil obtained from hydrothermal degradation of lignin is a promising material for phenol formaldehyde adhesive synthesis. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparison of phenol and sodium hydroxide chemical matricectomies for the treatment of ingrowing toenails.

PubMed

Bostanci, Seher; Kocyigit, Pelin; Gürgey, Erbak

2007-06-01

Chemical matricectomy is performed mainly by two agents: phenol and sodium hydroxide. Both agents have excellent cure rates, but there are no data about the comparison of postoperative healing periods. This study was designed to compare the postoperative morbidity rates of sodium hydroxide and phenol matricectomies. Forty-six patients with 154 ingrowing nail sides were treated with either sodium hydroxide or phenol matricectomy. In the postoperative period, the patients were evaluated for the duration and severity of pain, drainage, and peripheral tissue destruction; complete healing periods; and overall success rates. The incidence of pain was higher in the sodium hydroxide group on the first visit, on the second day, but all patients became pain-free after that. The incidence and duration of drainage and peripheral tissue destruction was significantly higher in the phenol group. The mean period for complete recovery was 10.8 days in the sodium hydroxide group, whereas it was 18.02 days in the phenol group. The overall success rates in the sodium hydroxide and phenol groups were found to be 95.1 and 95.8%, respectively. Both sodium hydroxide and phenol are effective agents giving high success rates, but sodium hydroxide causes less postoperative morbidity and provides faster recovery.

Extraction of phenol in wastewater with annular centrifugal contactors.

PubMed

Xu, Jin-Quan; Duan, Wu-Hua; Zhou, Xiu-Zhu; Zhou, Jia-Zhen

2006-04-17

Solvent extraction is an effective way to treat and recover the phenolic compounds from the high content phenolic wastewater at present. The experimental study on treating the wastewater containing phenol has been carried out with QH-1extractant (the amine mixture) and annular centrifugal contactors. The distribution ratio of phenol was 108.6 for QH-1-phenol system. The mass-transfer process of phenol for the system was mainly controlled by diffusion. When the flow ratio (aqueous/organic) was changed from 1/1 to 4/1, the rotor speed was changed from 2500 to 4000 r/min, and the total flow of two phases was changed from 20 to 70 mL/min, the mass-transfer efficiency E of the single-stage centrifugal contactor was more than 95%. When the flow ratio was changed from 4.4/1 to 4.9/1, the rotor speed was 3000 r/min, and the total flow of two phases was changed from 43.0 to 47.0 mL/min, the extraction rate rho of the three-stage cascade was more than 99%. When 15% NaOH was used for stripping of phenol in QH-1, the stripping efficiency of the three-stage cascade was also more than 99% under the experimental conditions.

Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS

PubMed Central

Tasioula-Margari, Maria; Tsabolatidou, Eleftheria

2015-01-01

The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected. PMID:26783843

Phenols in hydrothermal petroleums and sediment bitumen from Guaymas Basin, Gulf of California

NASA Technical Reports Server (NTRS)

Simoneit, B. R.; Leif, R. N.; Ishiwatari, R.

1996-01-01

The aliphatic, aromatic and polar (NSO) fractions of seabed petroleums and sediment bitumen extracts from the Guaymas Basin hydrothermal system have been analyzed by gas chromatography and gas chromatography-mass spectrometry (free and silylated). The oils were collected from the interiors and exteriors of high temperature hydrothermal vents and represent hydrothermal pyrolyzates that have migrated to the seafloor by hydrothermal fluid circulation. The downcore sediments are representative of both thermally unaltered and thermally altered sediments. The survey has revealed the presence of oxygenated compounds in samples with a high degree of thermal maturity. Phenols are one class of oxygenated compounds found in these samples. A group of methyl-, dimethyl- and trimethyl-isoprenoidyl phenols (C27-C29) is present in all of the seabed NSO fractions, with the methyl- and dimethyl-isoprenoidyl phenols occurring as major components, and a trimethyl-isoprenoidyl phenol as a minor component. A homologous series of n-alkylphenols (C13-C33) has also been found in the seabed petroleums. These phenols are most likely derived from the hydrothermal alteration of sedimentary organic matter. The n-alkylphenols are probably synthesized under hydrothermal conditions, but the isoprenoidyl phenols are probably hydrothermal alteration products of natural product precursors. The suites of phenols do not appear to be useful tracers of high temperature hydrothermal processes.

Occurrence, Ecological and Human Health Risks, and Seasonal Variations of Phenolic Compounds in Surface Water and Sediment of a Potential Polluted River Basin in China.

PubMed

Zhou, Mo; Zhang, Jiquan; Sun, Caiyun

2017-09-27

Five phenolic compounds in water and sediment of Yinma River Basin were investigated. The average concentration of phenol was the highest in water samples as well as in sediment samples during the wet season, 101.68 ng/L and 127.76 ng/g, respectively. 2,4,6-Trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP) was not detected in some sampling sites. Shitou Koumen Reservoir and the neighboring area were the severest areas of phenolic pollution. The lower reach was more polluted in three water seasons than the middle reach and upper reach. Phenol had ecological risks in sediment during three water seasons. 2-Nitrophenol (2-NP) and 2,4-dichlorophenol (2,4-DCP) had ecological risks in sediment in both the normal and wet season. The concentrations of five phenolic compounds from high to low were in the wet season, normal season, and dry season in water and sediment, respectively. There were middle risks in water of total concentrations for five phenolic compounds in several sampling sites. Total concentrations for five phenolic compounds in sediment had high ecological risks in all sampling sites. However, there was no human health risk in the Yinma River Basin.

Diversity and degradation mechanism of an anaerobic bacterial community treating phenolic wastewater with sulfate as an electron acceptor.

PubMed

Guo, X J; Lu, Z Y; Wang, P; Li, H; Huang, Z Z; Lin, K F; Liu, Y D

2015-10-01

Petrochemical wastewater often contains high concentrations of phenol and sulfate that must be properly treated to meet discharge standards. This study acclimated anaerobic-activated sludge to treat saline phenolic wastewater with sulfate reduction and clarified the diversity and degradation mechanism of the microbial community. The active sludge in an upflow anaerobic sludge blanket (UASB) reactor could remove 90 % of phenol and maintain the effluent concentration of SO4 (2-) below 400 mg/L. Cloning and sequencing showed that Clostridium spp. and Desulfotomaculum spp. were major phenol-degrading bacteria. Phenol was probably degraded through the carboxylation pathway and sulfate reduction catalyzed by adenosine-5'-phosphosulfate (APS) reductase and dissimilatory sulfite reductase (DSR). A real-time polymerase chain reaction (RT-PCR) showed that as phenol concentration increased, the quantities of 16S rRNA gene, dsrB, and mcrA in the sludge all decreased. The relative abundance of dsrB dropped to 12.46 %, while that of mcrA increased to 56.18 %. The change in the electron flow ratio suggested that the chemical oxygen demand (COD) was removed mainly by sulfate-reducing bacteria under a phenol concentration of 420 mg/L, whereas it was removed mainly by methanogens above 630 mg/L.

Physicochemical properties of natural phenolics from grapes and olive oil byproducts and their antioxidant activity in frozen horse mackerel fillets.

PubMed

Pazos, Manuel; Alonso, Ana; Fernández-Bolaños, Juan; Torres, Josep L; Medina, Isabel

2006-01-25

The reducing and chelating capacities and the affinity for the incorporation into the fish muscle of grape procyanidins, hydroxytyrosol, and propyl gallate were studied together with their antioxidant activity in frozen horse mackerel (Trauchurus trauchurus) fillets. Fillets were supplemented with phenolic antioxidants by (a) spraying an aqueous phenolic solution, (b) glazing with an aqueous phenolic solution, and (c) a previous washing of fillets with water plus spraying an aqueous phenolic solution. The effect of washing on the endogenous pro-oxidant/antioxidant balance of the fillets was also determined. All phenolic compounds were effective delaying lipid oxidation in the fish fillets. The order of antioxidant efficiency in spraying and glazing was propyl gallate > hydroxytyrosol > procyanidins, which was similar to the reducing power of these phenolics, but did not show any correlation with their chelating capacity and their affinity to the fish muscle. Washing the fillets with water prior to spraying phenols increased synergistically the antioxidant activity of grape procyanidins and changed the relative antioxidant efficiency to propyl gallate approximately procyanidins > hydroxytyrosol. This synergism may be a result of a better distribution of the procyanidins onto the fillet surface because of the residual water that remained on the fillets surface after washing.

Development of Phenol-Enriched Olive Oil with Phenolic Compounds Extracted from Wastewater Produced by Physical Refining

PubMed Central

Taglieri, Isabella; Nari, Anita; Andrich, Gianpaolo; Terzuoli, Erika; Donnini, Sandra; Nicolella, Cristiano; Zinnai, Angela

2017-01-01

While in the last few years the use of olive cake and mill wastewater as natural sources of phenolic compounds has been widely considered and several studies have focused on the development of new extraction methods and on the production of functional foods enriched with natural antioxidants, no data has been available on the production of a phenol-enriched refined olive oil with its own phenolic compounds extracted from wastewater produced during physical refining. In this study; we aimed to: (i) verify the effectiveness of a multi-step extraction process to recover the high-added-value phenolic compounds contained in wastewater derived from the preliminary washing degumming step of the physical refining of vegetal oils; (ii) evaluate their potential application for the stabilization of olive oil obtained with refined olive oils; and (iii) evaluate their antioxidant activity in an in vitro model of endothelial cells. The results obtained demonstrate the potential of using the refining wastewater as a source of bioactive compounds to improve the nutraceutical value as well as the antioxidant capacity of commercial olive oils. In the conditions adopted, the phenolic content significantly increased in the prototypes of phenol-enriched olive oils when compared with the control oil. PMID:28829365

Experimental and modeling studies of ultrasound-assisted release of phenolics from oak chips into model wine.

PubMed

Tao, Yang; Zhang, Zhihang; Sun, Da-Wen

2014-09-01

The enhancement of release of oak-related compounds from oak chips during wine aging with oak chips may interest the winemaking industry. In this study, the 25-kHz ultrasound waves were used to intensify the mass transfer of phenolics from oak chips into a model wine. The influences of acoustic energy density (6.3-25.8 W/L) and temperature (15-25 °C) on the release kinetics of total phenolics were investigated systematically. The results exhibited that the total phenolic yield released was not affected by acoustic energy density significantly whereas it increased with the increase of temperature during sonication. Furthermore, to describe the mechanism of mass transfer of phenolics in model wine under ultrasonic field, the release kinetics of total phenolics was simulated by both a second-order kinetic model and a diffusion model. The modeling results revealed that the equilibrium concentration of total phenolics in model wine, the initial release rate and effective diffusivity of total phenolics generally increased with acoustic energy density and temperature. In addition, temperature had a negative effect on the second-order release rate constant whereas acoustic energy density had an opposite effect. Copyright © 2014 Elsevier B.V. All rights reserved.

Engineering of solvent-tolerant Pseudomonas putida S12 for bioproduction of phenol from glucose.

PubMed

Wierckx, Nick J P; Ballerstedt, Hendrik; de Bont, Jan A M; Wery, Jan

2005-12-01

Efficient bioconversion of glucose to phenol via the central metabolite tyrosine was achieved in the solvent-tolerant strain Pseudomonas putida S12. The tpl gene from Pantoea agglomerans, encoding tyrosine phenol lyase, was introduced into P. putida S12 to enable phenol production. Tyrosine availability was a bottleneck for efficient production. The production host was optimized by overexpressing the aroF-1 gene, which codes for the first enzyme in the tyrosine biosynthetic pathway, and by random mutagenesis procedures involving selection with the toxic antimetabolites m-fluoro-dl-phenylalanine and m-fluoro-l-tyrosine. High-throughput screening of analogue-resistant mutants obtained in this way yielded a P. putida S12 derivative capable of producing 1.5 mM phenol in a shake flask culture with a yield of 6.7% (mol/mol). In a fed-batch process, the productivity was limited by accumulation of 5 mM phenol in the medium. This toxicity was overcome by use of octanol as an extractant for phenol in a biphasic medium-octanol system. This approach resulted in accumulation of 58 mM phenol in the octanol phase, and there was a twofold increase in the overall production compared to a single-phase fed batch.

Rapid profiling of polymeric phenolic acids in Salvia miltiorrhiza by hybrid data-dependent/targeted multistage mass spectrometry acquisition based on expected compounds prediction and fragment ion searching.

PubMed

Shen, Yao; Feng, Zijin; Yang, Min; Zhou, Zhe; Han, Sumei; Hou, Jinjun; Li, Zhenwei; Wu, Wanying; Guo, De-An

2018-04-01

Phenolic acids are the major water-soluble components in Salvia miltiorrhiza (>5%). According to previous studies, many of them contribute to the cardiovascular effects and antioxidant effects of S. miltiorrhiza. Polymeric phenolic acids can be considered as the tanshinol derived metabolites, e.g., dimmers, trimers, and tetramers. A strategy combined with tanshinol-based expected compounds prediction, total ion chromatogram filtering, fragment ion searching, and parent list-based multistage mass spectrometry acquisition by linear trap quadropole-orbitrap Velos mass spectrometry was proposed to rapid profile polymeric phenolic acids in S. miltiorrhiza. More than 480 potential polymeric phenolic acids could be screened out by this strategy. Based on the fragment information obtained by parent list-activated data dependent multistage mass spectrometry acquisition, 190 polymeric phenolic acids were characterized by comparing their mass information with literature data, and 18 of them were firstly detected from S. miltiorrhiza. Seven potential compounds were tentatively characterized as new polymeric phenolic acids from S. miltiorrhiza. This strategy facilitates identification of polymeric phenolic acids in complex matrix with both selectivity and sensitivity, which could be expanded for rapid discovery and identification of compounds from complex matrix. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Occurrence, Ecological and Human Health Risks, and Seasonal Variations of Phenolic Compounds in Surface Water and Sediment of a Potential Polluted River Basin in China

PubMed Central

Zhou, Mo; Sun, Caiyun

2017-01-01

Five phenolic compounds in water and sediment of Yinma River Basin were investigated. The average concentration of phenol was the highest in water samples as well as in sediment samples during the wet season, 101.68 ng/L and 127.76 ng/g, respectively. 2,4,6-Trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP) was not detected in some sampling sites. Shitou Koumen Reservoir and the neighboring area were the severest areas of phenolic pollution. The lower reach was more polluted in three water seasons than the middle reach and upper reach. Phenol had ecological risks in sediment during three water seasons. 2-Nitrophenol (2-NP) and 2,4-dichlorophenol (2,4-DCP) had ecological risks in sediment in both the normal and wet season. The concentrations of five phenolic compounds from high to low were in the wet season, normal season, and dry season in water and sediment, respectively. There were middle risks in water of total concentrations for five phenolic compounds in several sampling sites. Total concentrations for five phenolic compounds in sediment had high ecological risks in all sampling sites. However, there was no human health risk in the Yinma River Basin. PMID:28953252

Determination of the phenolic content, profile, and antioxidant activity of seeds from nine tree peony (Paeonia section Moutan DC.) species native to China.

PubMed

Zhang, Xiao-Xiao; Shi, Qian-Qian; Ji, Duo; Niu, Li-Xin; Zhang, Yan-Long

2017-07-01

As an important resource of functional food, the seeds of tree peony are rich in phenolic compounds, which are associated with antioxidant activity. However, so far there has not been systematic study on phenolic compositions and antioxidant activity of the seeds from wild tree peony species. The aim of this study was to determine the phenolic content, antioxidant compounds and antioxidant activity of seeds from nine tree peony species native to China. Among the seed samples, Paeonia rockii had the highest total flavonoid content, strongest DPPH and ABTS radical scavenging activities, and strongest cupric reducing capacity; P. decomposita subsp. rotundiloba had the highest total phenolic and flavanol contents, as well as the strongest hydroxyl radical scavenging activity. Sixteen individual phenolic compounds were quantitatively measured, with (+)-catechin being the most abundant component. The content of the phenolic compounds luteolin, paeonol, and the total flavonoid content were significantly correlated with four antioxidant activities. Hierarchical cluster analysis showed that P. rockii and P. decomposita subsp. rotundiloba could be clustered in a group having a high phenolic content and strong antioxidant activity. These results suggest P. rockii and P. decomposita subsp. rotundiloba are the most promising candidates as useful sources of natural antioxidants. Copyright © 2017. Published by Elsevier Ltd.

Phenolic acids of the two major blueberry species in the US Market and their antioxidant and anti-inflammatory activities.

PubMed

Kang, Jie; Thakali, Keshari M; Jensen, Gitte S; Wu, Xianli

2015-03-01

Highbush (cultivated) and lowbush (wild) are the two major blueberry species in the US market. Eight phenolic acids were detected and quantified from these two species by HPLC-MS. Chlorogenic acid was found to be the predominant phenolic acid in both species, with 0.44 mg/g fresh weight in lowbush blueberries and 0.13 mg/g fresh weight in highbush blueberries. Total phenolic content in lowbush blueberries is over three times higher than that of highbush blueberries. The phenolic acid mixtures representing those in the two species were prepared by using authentic standards to assess their contribution to total antioxidant and anti-inflammatory activities of the whole berries. Neither lowbush nor highbush blueberry phenolic acid mixture contributed significantly to the total antioxidant capacity of their relevant whole berries measured by oxygen radical absorbance capacity (ORAC). Both phenolic acid mixtures were able to enter the cell and showed in cell antioxidant activities from the cell based antioxidant protection of erythrocytes (CAP-e) assay. Lowbush blueberry phenolic acid mixture was found to show anti-inflammatory activities by inhibiting the nuclear factor-κB (NF-κB) activation and the production of inflammatory cytokines (TNF-α and IL-6) at the high dose.

Phenol removal pretreatment process

DOEpatents

Hames, Bonnie R.

2004-04-13

A process for removing phenols from an aqueous solution is provided, which comprises the steps of contacting a mixture comprising the solution and a metal oxide, forming a phenol metal oxide complex, and removing the complex from the mixture.

Effects of abscisic acid, gibberellin, ethylene and their interactions on production of phenolic acids in salvia miltiorrhiza bunge hairy roots.

PubMed

Liang, Zongsuo; Ma, Yini; Xu, Tao; Cui, Beimi; Liu, Yan; Guo, Zhixin; Yang, Dongfeng

2013-01-01

Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants because of its excellent performance in treating coronary heart disease. Phenolic acids mainly including caffeic acid, rosmarinic acid and salvianolic acid B are a group of active ingredients in S. miltiorrhiza. Abscisic acid (ABA), gibberellin (GA) and ethylene are three important phytohormones. In this study, effects of the three phytohormones and their interactions on phenolic production in S. miltiorrhiza hairy roots were investigated. The results showed that ABA, GA and ethylene were all effective to induce production of phenolic acids and increase activities of PAL and TAT in S. miltiorrhiza hairy roots. Effects of phytohormones were reversed by their biosynthetic inhibitors. Antagonistic actions between the three phytohormones played important roles in the biosynthesis of phenolic acids. GA signaling is necessary for ABA and ethylene-induced phenolic production. Yet, ABA and ethylene signaling is probably not necessary for GA3-induced phenolic production. The complex interactions of phytohormones help us reveal regulation mechanism of secondary metabolism and scale-up production of active ingredients in plants.

Effects of Abscisic Acid, Gibberellin, Ethylene and Their Interactions on Production of Phenolic Acids in Salvia miltiorrhiza Bunge Hairy Roots

PubMed Central

Xu, Tao; Cui, Beimi; Liu, Yan; Guo, Zhixin; Yang, Dongfeng

2013-01-01

Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants because of its excellent performance in treating coronary heart disease. Phenolic acids mainly including caffeic acid, rosmarinic acid and salvianolic acid B are a group of active ingredients in S. miltiorrhiza. Abscisic acid (ABA), gibberellin (GA) and ethylene are three important phytohormones. In this study, effects of the three phytohormones and their interactions on phenolic production in S. miltiorrhiza hairy roots were investigated. The results showed that ABA, GA and ethylene were all effective to induce production of phenolic acids and increase activities of PAL and TAT in S. miltiorrhiza hairy roots. Effects of phytohormones were reversed by their biosynthetic inhibitors. Antagonistic actions between the three phytohormones played important roles in the biosynthesis of phenolic acids. GA signaling is necessary for ABA and ethylene-induced phenolic production. Yet, ABA and ethylene signaling is probably not necessary for GA3-induced phenolic production. The complex interactions of phytohormones help us reveal regulation mechanism of secondary metabolism and scale-up production of active ingredients in plants. PMID:24023778

Phenolic composition of pomegranate peel extracts using an liquid chromatography-mass spectrometry approach with silica hydride columns.

PubMed

Young, Joshua E; Pan, Zhongli; Teh, Hui Ean; Menon, Veena; Modereger, Brent; Pesek, Joseph J; Matyska, Maria T; Dao, Lan; Takeoka, Gary

2017-04-01

The peels of different pomegranate cultivars (Molla Nepes, Parfianka, Purple Heart, Wonderful and Vkunsyi) were compared in terms of phenolic composition and total phenolics. Analyses were performed on two silica hydride based stationary phases: phenyl and undecanoic acid columns. Quantitation was accomplished by developing a liquid chromatography with mass spectrometry approach for separating different phenolic analytes, initially in the form of reference standards and then with pomegranate extracts. The high-performance liquid chromatography columns used in the separations had the ability to retain a wide polarity range of phenolic analytes, as well as offering beneficial secondary selectivity mechanisms for resolving the isobaric compounds, catechin and epicatechin. The Vkunsyi peel extract had the highest concentration of phenolics (as determined by liquid chromatography with mass spectrometry) and was the only cultivar to contain the important compound punicalagin. The liquid chromatography with mass spectrometry data were compared to the standard total phenolics content as determined by using the Folin-Ciocalteu assay. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Soymilk enriched with green coffee phenolics - Antioxidant and nutritional properties in the light of phenolics-food matrix interactions.

PubMed

Sęczyk, Łukasz; Świeca, Michał; Gawlik-Dziki, Urszula

2017-05-15

This study investigated the effect of soymilk fortification with green coffee extract (GCE) on phenolic contents, antioxidant capacity, relative in vitro digestibility of proteins and starch, and consumer acceptance. Special attention was paid to the effect of phenolics-food matrix interactions on fortification efficiency. Soymilk was enriched with GCE extracts containing 0.025-1mg of phenolics per 1mL-samples M1-M6. Compared to control, an increase in phenolic contents of up to 70% (M6) was observed for potentially bioaccessible fractions (AD). The antiradical activity and reducing power were also about 1.9 and 10.1 times higher, respectively. However, the determined phenolic and antioxidant activities differed from those predicted. Fortification improved the digestibility of nutrients when higher doses of GCE was introduced (M4-M6). The addition of GCE at an adequate dose allowed the production of a beverage with elevated hedonic properties. In conclusion, fortification was a successful in improving the pro-health status of soymilk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sclerotherapy of testicular hydroceles with 3% aqueous phenol.

PubMed

Ozdemir, E

1996-06-01

With the evolution of minimally invasive approaches in medicine, phenol has regained its popularity for the sclerotherapy of testicular hydroceles. Together with reported efficiency and safety of 2.5% phenol in the literature, the recently proved safety of 3% phenol in esophageal variceal sclerotherapy has led us to perform a prospective study to lessen the number of sessions. Sclerotherapy with 3% aqueous phenol was applied on an ambulatory basis to 23 patients with 31 hydroceles, who were over 40 years old and who had no fertility problems. The over-all cure rate was 96% with an average follow-up of 3 years, and 58% of the hydroceles required only one session of treatment. The average number of treatment sessions was 2.2 (range; 1-7). One patient with a history of herniorraphy 10 years earlier, was treated surgically following failure of seven sclerotherapy sessions. Phenol, a sclerosant superior to other conventional agents including tetracyclines, requires neither anesthetics nor prophylactic antibiotics. Our findings indicate that sclerotherapy with 3% phenol is an effective, economical and safe form of therapy for patients with hydrocele.

Role of Hydrogen Bonding in Photoinduced Electron-Proton Transfer from Phenols to a Polypyridine Ru Complex with a Proton-Accepting Ligand

DOE PAGES

Lymar, Sergei V.; Ertem, Mehmed Z.; Lewandowska-Andralojc, Anna; ...

2017-08-09

Electron-proton transfer, EPT, from phenols to a triplet MLCT-excited Ru polypyridine complex containing an uncoordinated nitrogen site, 1(T), can be described by a kinetic model that accounts for the H-bonding of 1(T) to phenol, 1(T) to solvent, and phenol to solvent. The latter plays a major role in the kinetic solvent effect and commonly precludes simultaneous determination of the EPT rate constant and 1(T)-phenol H-bonding constant. A number of these quantities previously reported for similar systems are shown to be in error due to an inconsistent data analysis. In conclusion, control experiments replacing either 1(T) by its structural isomer withmore » a sterically screened nitrogen site or phenol by its H-bonding surrogate, trifluoroethanol, and the observation of negative activation enthalpies for the overall reactions between 1(T) and phenols lend support to the proposed model and provide evidence for the formation of a precursor H-bonded complex between the reactants, which is a prerequisite for EPT.« less

Potentiation of the bioavailability of blueberry phenolic compounds by co-ingested grape phenolic compounds in mice, revealed by targeted metabolomic profiling in plasma and feces.

PubMed

Dudonné, Stéphanie; Dal-Pan, Alexandre; Dubé, Pascal; Varin, Thibault V; Calon, Frédéric; Desjardins, Yves

2016-08-10

The low bioavailability of dietary phenolic compounds, resulting from poor absorption and high rates of metabolism and excretion, is a concern as it can limit their potential beneficial effects on health. Targeted metabolomic profiling in plasma and feces of mice supplemented for 15 days with a blueberry extract, a grape extract or their combination revealed significantly increased plasma concentrations (3-5 fold) of blueberry phenolic metabolites in the presence of a co-ingested grape extract, associated with an equivalent decrease in their appearance in feces. Additionally, the repeated daily administration of the blueberry-grape combination significantly increased plasma phenolic concentrations (2-3-fold) compared to animals receiving only a single acute dose, with no such increase being observed with individual extracts. These findings highlight a positive interaction between blueberry and grape constituents, in which the grape extract enhanced the absorption of blueberry phenolic compounds. This study provides for the first time in vivo evidence of such an interaction occurring between co-ingested phenolic compounds from fruit extracts leading to their improved bioavailability.

Digestibility of (Poly)phenols and Antioxidant Activity in Raw and Cooked Cactus Cladodes ( Opuntia ficus-indica).

PubMed

De Santiago, Elsy; Pereira-Caro, Gema; Moreno-Rojas, José Manuel; Cid, Concepción; De Peña, María-Paz

2018-05-29

This study aims to investigate whether heat treatment applied to cactus cladodes influences the bioaccessibility of their (poly)phenolic compounds after simulated gastric and intestinal digestion. A total of 45 (poly)phenols were identified and quantified in raw and cooked cactus cladodes by ultra high performance liquid chromatography photodiode array detector high resolution mass spectrometry. Both flavonoids (60-68% total), mainly isorhamnetin derivatives, and phenolic acids (32-40%) with eucomic acids as the predominant ones significantly ( p < 0.05) increased with microwaving and griddling processes. After in vitro gastrointestinal digestion, 55-64% of the total (poly)phenols of cooked cactus cladodes remained bioaccessible versus 44% in raw samples. Furthermore, digestive conditions and enzymes degraded or retained more flavonoids (37-63% bioaccessibility) than phenolic acids (56-87% bioaccessibility). Microwaved cactus cladodes contributed the highest amount of (poy)phenols (143.54 mg/g dm) after gastrointestinal process, followed by griddled samples (133.98 mg/g dm), showing the highest antioxidant capacity. Additionally, gastrointestinal digestion induced isomerizations among the three stereoisomeric forms of piscidic and eucomic acids.

Role of Hydrogen Bonding in Photoinduced Electron-Proton Transfer from Phenols to a Polypyridine Ru Complex with a Proton-Accepting Ligand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lymar, Sergei V.; Ertem, Mehmed Z.; Lewandowska-Andralojc, Anna

Electron-proton transfer, EPT, from phenols to a triplet MLCT-excited Ru polypyridine complex containing an uncoordinated nitrogen site, 1(T), can be described by a kinetic model that accounts for the H-bonding of 1(T) to phenol, 1(T) to solvent, and phenol to solvent. The latter plays a major role in the kinetic solvent effect and commonly precludes simultaneous determination of the EPT rate constant and 1(T)-phenol H-bonding constant. A number of these quantities previously reported for similar systems are shown to be in error due to an inconsistent data analysis. In conclusion, control experiments replacing either 1(T) by its structural isomer withmore » a sterically screened nitrogen site or phenol by its H-bonding surrogate, trifluoroethanol, and the observation of negative activation enthalpies for the overall reactions between 1(T) and phenols lend support to the proposed model and provide evidence for the formation of a precursor H-bonded complex between the reactants, which is a prerequisite for EPT.« less

Phenolic acids and flavonoids of peanut by-products: Antioxidant capacity and antimicrobial effects.

PubMed

de Camargo, Adriano Costa; Regitano-d'Arce, Marisa Aparecida Bismara; Rasera, Gabriela Boscariol; Canniatti-Brazaca, Solange Guidolin; do Prado-Silva, Leonardo; Alvarenga, Verônica Ortiz; Sant'Ana, Anderson S; Shahidi, Fereidoon

2017-12-15

Peanut skin (PS) and meal from dry-blanched peanuts (MDBP) were evaluated as sources of phenolic compounds. PS rendered the highest total phenolic content, antioxidant capacity towards ABTS radical cation, DPPH and hydroxyl radicals as well as reducing power. Phenolic acids were present in PS and MDBP whereas proanthocyanidins and monomeric flavonoids were found only in PS as identified by HPLC-DAD-ESI-MS n . Procyanidin-rich extracts prevented oxidation in non-irradiated and gamma-irradiated fish model system. Both extracts inhibited the growth of gram-positive (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Geobacillus stearothermophilus) and gram-negative bacteria (Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella Enteritidis, Salmonella Typhimurium, Escherichia coli). Regardless of the strain, phenolic acid-rich extracts showed the lowest minimum inhibitory capacity (MIC); therefore presenting higher antibacterial effect. The MIC of phenolic acid-rich extracts (24-49μgphenolics/mL) was higher but comparable to Ampicillin (10μg/mL). Thus, phenolics in PS and MDBP may serve as antioxidants and antimicrobial compounds. Copyright © 2017. Published by Elsevier Ltd.

Reactivity of food phenols with iron and copper ions: binding, dioxygen activation and oxidation mechanisms.

PubMed

Nkhili, Ezzohra; Loonis, Michèle; Mihai, Simona; El Hajji, Hakima; Dangles, Olivier

2014-06-01

In this work, the affinity of common dietary phenols (gallic acid, caffeic acid, catechin, and rutin) for iron and copper ions was quantitatively investigated in neutral phosphate buffer as well as the reactivity of the complexes toward dioxygen. Contrasting behaviors were observed: because of the competing phosphate ions, Fe(III) binding is much slower than Fe(II) binding, which is rapidly followed by autoxidation of Fe(II) into Fe(III). With both ions, O2 consumption and H2O2 production are modest and the phenolic ligands are only slowly oxidized. By contrast, metal-phenol binding is fast with both Cu(I) and Cu(II). With Cu(I), O2 consumption and H2O2 production are very significant and the phenolic ligands are rapidly oxidized into a complex mixture of oligomers. The corresponding mechanism with Cu(II) is hampered by the preliminary rate-determining step of Cu(II) reduction by the phenols. The consequences of these findings for the stability and antioxidant activity of plant phenols are discussed.

Detection of phenols using engineered bacteria

DOEpatents

Wise, Arlene A.; Kuske, Cheryl R.; Terwilliger, Thomas C.

2007-12-04

Detection of phenols using engineered bacteria. A biosensor can be created by placing a reporter gene under control of an inducible promoter. The reporter gene produces a signal when a cognate transcriptional activator senses the inducing chemical. Creation of bacterial biosensors is currently restricted by limited knowledge of the genetic systems of bacteria that catabolize xenobiotics. By using mutagenic PCR to change the chemical specificity of the Pseudomonas species CF600 DmpR protein, the potential for engineering novel biosensors for detection of phenols has been demonstrated. DmpR, a well-characterized transcriptional activator of the P. CF600's dmp operon mediates growth on simple phenols. Transcription from Po, the promoter heading the dmp operon, is activated when the sensor domain of DmpR interacts with phenol and mono-substituted phenols. By altering the sensor domain of the DmpR, a group of DmpR derivatives that activate transcription of a Po-lacZ fusion in response to eight of the EPA's eleven priority pollutant phenols has been created. The assays and the sensor domain mutations that alter the chemical specificity of DmpR is described.

Detection of phenols using engineered bacteria

DOEpatents

Wise, Arlene A.; Kuske, Cheryl R.; Terwilliger, Thomas C.

2004-08-10

Detection of phenols using engineered bacteria. A biosensor can be created by placing a reporter gene under control of an inducible promoter. The reporter gene produces a signal when a cognate transcriptional activator senses the inducing chemical. Creation of bacterial biosensors is currently restricted by limited knowledge of the genetic systems of bacteria that catabolize xenobiotics. By using mutagenic PCR to change the chemical specificity of the Pseudomonas species CF600 DmpR protein, the potential for engineering novel biosensors for detection of phenols has been demonstrated. DmpR, a well-characterized transcriptional activator of the P. CF600's dmp operon mediates growth on simple phenols. Transcription from Po, the promoter heading the dmp operon, is activated when the sensor domain of DmpR interacts with phenol and mono-substituted phenols. By altering the sensor domain of the DmpR, a group of DmpR derivatives that activate transcription of a Po-lacZ fusion in response to eight of the EPA's eleven priority pollutant phenols has been created. The assays and the sensor domain mutations that alter the chemical specificity of DmpR is described.

Bioavailability and pharmacokinetic profile of grape pomace phenolic compounds in humans.

PubMed

Castello, Fabio; Costabile, Giuseppina; Bresciani, Letizia; Tassotti, Michele; Naviglio, Daniele; Luongo, Delia; Ciciola, Paola; Vitale, Marilena; Vetrani, Claudia; Galaverna, Gianni; Brighenti, Furio; Giacco, Rosalba; Del Rio, Daniele; Mena, Pedro

2018-05-15

Grape pomace, the major byproduct of the wine and juice industry, is a relevant source of bioactive phenolic compounds. However, polyphenol bioavailability in humans is not well understood, and the inter-individual variability in the production of phenolic metabolites has not been comprehensively assessed to date. The pharmacokinetic and excretive profiles of phenolic metabolites after the acute administration of a drink made from red grape pomace was here investigated in ten volunteers. A total of 35 and 28 phenolic metabolites were quantified in urine and plasma, respectively. The main circulating metabolites included phenyl-γ-valerolactones, hydroxybenzoic acids, simple phenols, hydroxyphenylpropionic acids, hydroxycinnamates, and (epi)catechin phase II conjugates. A high inter-individual variability was shown both in urine and plasma samples, and different patterns of circulating metabolites were unravelled by applying unsupervised multivariate analysis. Besides the huge variability in the production of microbial metabolites of colonic origin, an important variability was observed due to phase II conjugates. These results are of interest to further understand the potential health benefits of phenolic metabolites on individual basis. Copyright © 2018 Elsevier Inc. All rights reserved.

Identification/quantification of free and bound phenolic acids in peel and pulp of apples (Malus domestica) using high resolution mass spectrometry (HRMS).

PubMed

Lee, Jihyun; Chan, Bronte Lee Shan; Mitchell, Alyson E

2017-01-15

Free and bound phenolic acids were measured in the pulp and peel of four varieties of apples using high resolution mass spectrometry. Twenty-five phenolic acids were identified and included: 8 hydroxybenzoic acids, 11 hydroxycinnamic acids, 5 hydroxyphenylacetic acids, and 1 hydoxyphenylpropanoic acid. Several phenolics are tentatively identified for the first time in apples and include: methyl gallate, ethyl gallate, hydroxy phenyl acetic acid, three phenylacetic acid isomers, 3-(4-hydroxyphenyl)propionic acid, and homoveratric acid. With exception of chlorogenic and caffeic acid, most phenolic acids were quantified for the first time in apples. Significant varietal differences (p<0.05) were observed in both peel and pulp. The levels of total phenolic acids were higher in the pulp as compared to apple peel (dry weight) in all varieties. Coumaroylquinic, protocatechuic, 4-hydroxybenzoic, vanillic and t-ferulic acids were present in free forms. With exception of chlorogenic acid, all other phenolic acids were present only as bound forms. Copyright © 2016 Elsevier Ltd. All rights reserved.

Postharvest changes in the phenolic profile of watercress induced by post-packaging irradiation and modified atmosphere packaging.

PubMed

Pinela, José; Barros, Lillian; Barreira, João C M; Carvalho, Ana Maria; Oliveira, M Beatriz P P; Santos-Buelga, Celestino; Ferreira, Isabel C F R

2018-07-15

The effects of γ-ray irradiation and modified atmosphere packaging (MAP) on watercress (Nasturtium officinale R. Br.) phenolic compounds were evaluated after 7-day storage at 4 °C. Irradiation doses of 1, 2 and 5 kGy were tested, as well as vacuum-packaging and MAP enriched with 100% N 2 and Ar. A non-irradiated, air-packaged control was included in all experiments. p-Coumaric acid was the most abundant compound in fresh watercress, followed by quercetin-3-O-sophoroside and isorhamnetin-O-hydroxyferuloylhexoside-O-hexoside. Four kaempferol glycoside derivatives were identified for the first time in this species. In general, flavonoids predominated over phenolic acids. Samples stored under vacuum and irradiated at 2 kGy revealed lower phenolic levels. Ar-enriched MAP and control conditions preserved the initial phenolic content. The 5 kGy dose also maintained concentrations of flavonoids and total phenolic compounds, but increased the phenolic acids content. Additionally, flavonoids were found strongly correlated to DPPH scavenging activity and β-carotene bleaching inhibition capacity. Copyright © 2018 Elsevier Ltd. All rights reserved.

High-Throughput Screening for a Moderately Halophilic Phenol-Degrading Strain and Its Salt Tolerance Response

PubMed Central

Lu, Zhi-Yan; Guo, Xiao-Jue; Li, Hui; Huang, Zhong-Zi; Lin, Kuang-Fei; Liu, Yong-Di

2015-01-01

A high-throughput screening system for moderately halophilic phenol-degrading bacteria from various habitats was developed to replace the conventional strain screening owing to its high efficiency. Bacterial enrichments were cultivated in 48 deep well microplates instead of shake flasks or tubes. Measurement of phenol concentrations was performed in 96-well microplates instead of using the conventional spectrophotometric method or high-performance liquid chromatography (HPLC). The high-throughput screening system was used to cultivate forty-three bacterial enrichments and gained a halophilic bacterial community E3 with the best phenol-degrading capability. Halomonas sp. strain 4-5 was isolated from the E3 community. Strain 4-5 was able to degrade more than 94% of the phenol (500 mg·L−1 starting concentration) over a range of 3%–10% NaCl. Additionally, the strain accumulated the compatible solute, ectoine, with increasing salt concentrations. PCR detection of the functional genes suggested that the largest subunit of multicomponent phenol hydroxylase (LmPH) and catechol 1,2-dioxygenase (C12O) were active in the phenol degradation process. PMID:26020478

Influence of fungal endophyte infection on phenolic content and antioxidant activity in grasses: interaction between Lolium perenne and different strains of Neotyphodium lolii.

PubMed

Qawasmeh, Abdelqader; Obied, Hassan K; Raman, Anantanarayanan; Wheatley, Warwick

2012-04-04

Lolium perenne is a major forage and turf grass, which is often naturally infected with a "wild-type" strain (E(WT)) of the fungal endophyte Neotyphodium lolii , establishing a symbiotic relationship. In this study, the impacts of different strains wild type E(WT), AR1 (E(AR1)) and AR37 (E(AR37)), of N. lolii on the phenolic profile, phenolic content, and antioxidant capacity of L. perenne were examined. Samples could be ranked according to their phenol content as follows: E(AR1) > E(AR37) ≥ E(-) > E(WT). Radical-scavenging assays showed the same relative ranking of extracts. Flavonoid glycosides and hydroxycinnamic acids were the most abundant polyphenols in L. perenne extracts. Chlorogenic acid and its derivatives were the major compounds responsible for the antioxidant activity. Infection with N. lolii significantly influenced L. perenne phenolic content and antioxidant activity. In conclusion, changes in phenolic composition were merely quantitative. Endophyte infection can have zero, positive, or negative effect on phenol content depending on the endophyte strain.

Determination of contents and antioxidant activity of free and bound phenolics compounds and in vitro digestibility of commercial black and red rice (Oryza sativa L.) varieties.

PubMed

Sumczynski, Daniela; Kotásková, Eva; Družbíková, Helena; Mlček, Jiří

2016-11-15

Black and red rices (Oryza sativa L.) were analysed for total flavonoids and phenolics and the HPLC profile including both free and bound phenolic fractions. Moreover, antioxidant activity and in vitro digestibility was determined. Content of flavonoids and polyphenols as well as antioxidant activity was higher in free phenolic fractions. Bound flavonoids in black rices were not significant contributors to antioxidant activity. The main free phenolics in black rices were ferulic, protocatechuic and trans-p-coumaric acids, while the major free phenolics in red rices were catechin, protocatechuic and caffeic acids. The main bound phenolics in black rices were ferulic and vanillic acids and quercetin, in red rice types, they were ferulic, syringic, trans-p-coumaric acids and quercetin. Newly, the presence of m-coumaric acid in red rices was detected. Steam cooked rices showed very high levels of organic matter digestibility, whereas red rices were significantly more digestible than black rices (p<0.05). Copyright © 2016 Elsevier Ltd. All rights reserved.

Morganella morganii bacteria produces phenol as the sex pheromone of the New Zealand grass grub from tyrosine in the colleterial gland

NASA Astrophysics Data System (ADS)

Marshall, D. G.; Jackson, T. A.; Unelius, C. R.; Wee, S. L.; Young, S. D.; Townsend, R. J.; Suckling, D. M.

2016-08-01

Costelytra zealandica (Coleoptera: Scarabeidae) is a univoltine endemic species that has colonised and become a major pest of introduced clover and ryegrass pastures that form about half of the land area of New Zealand. Female beetles were previously shown to use phenol as their sex pheromone produced by symbiotic bacteria in the accessory or colleterial gland. In this study, production of phenol was confirmed from the female beetles, while bacteria were isolated from the gland and tested for attractiveness towards grass grub males in traps in the field. The phenol-producing bacterial taxon was identified by partial sequencing of the 16SrRNA gene, as Morganella morganii. We then tested the hypothesis that the phenol sex pheromone is biosynthesized from the amino acid tyrosine by the bacteria. This was shown to be correct, by addition of isotopically labelled tyrosine (13C) to the bacterial broth, followed by detection of the labelled phenol by SPME-GCMS. Elucidation of this pathway provides specific evidence how the phenol is produced as an insect sex pheromone by a mutualistic bacteria.

Lipid encapsulated phenolic compounds by fluidization

USDA-ARS?s Scientific Manuscript database

Phenolic compounds exhibit antioxidant and antimicrobial activities with applications as functional food and feed additives. Ferulic acid, a phenolic compound present in grain crops and lignocellulose biomass, was encapsulated with saturated triglycerides using a laboratory fluidizer. Stability of t...

Method for making adhesive from biomass

DOEpatents

Russell, Janet A.; Riemath, William F.

1985-01-01

A method is described for making adhesive from biomass. A liquefaction oil is prepared from lignin-bearing plant material and a phenolic fraction is extracted therefrom. The phenolic fraction is reacted with formaldehyde to yield a phenol-formaldehyde resin.

Water hyacinths for removal of phenols from polluted waters

NASA Technical Reports Server (NTRS)

Wolverton, B. C.

1975-01-01

Removal of phenol by water hyacinths (Eichhornia crassipes (Mart.) Solms) in static water was investigated. 2.75 g dry weight of this aquatic plant demonstrated the ability to absorb 100 mg of phenol per plant per 72 hours from distilled water, river water, and bayou water. One hectare of water hyacinth plants is shown to be potentially capable of removing 160 kg of phenol per 72 hours from waters polluted with this chemical.

Copper-catalyzed oxidative C-O bond formation of 2-acyl phenols and 1,3-dicarbonyl compounds with ethers: direct access to phenol esters and enol esters.

PubMed

Park, Jihye; Han, Sang Hoon; Sharma, Satyasheel; Han, Sangil; Shin, Youngmi; Mishra, Neeraj Kumar; Kwak, Jong Hwan; Lee, Cheong Hoon; Lee, Jeongmi; Kim, In Su

2014-05-16

A copper-catalyzed oxidative coupling of 2-carbonyl-substituted phenols and 1,3-dicarbonyl compounds with a wide range of dibenzyl or dialkyl ethers is described. This protocol provides an efficient preparation of phenol esters and enol esters in good yields with high chemoselectivity. This method represents an alternative protocol for classical esterification reactions.

Exploratory Development of Corrosion Inhibiting Primers

DTIC Science & Technology

1977-07-01

Phenolic Hardener From previous studies, phenol formaldehyde resins of the novolac (two-step) type have given superior properties when used to cure epoxy...novolacs and three resole (one-step) type phenol- formaldehyde resins which also perform as epoxide curing agents. First, Model #1, as de;crihed in Section...results. Varcum 4326 resin was chosen at this stage for further use with the model systems. It is a low molecular weight phenol- formaldehyde resin used

Scope and limitations of the Heck-Matsuda-coupling of phenol diazonium salts and styrenes: a protecting-group economic synthesis of phenolic stilbenes.

PubMed

Schmidt, Bernd; Elizarov, Nelli; Berger, René; Hölter, Frank

2013-06-14

4-Phenol diazonium salts undergo Pd-catalyzed Heck reactions with various styrenes to 4'-hydroxy stilbenes. In almost all cases higher yields and fewer side products were observed, compared to the analogous 4-methoxy benzene diazonium salts. In contrast, the reaction fails completely with 2- and 3-phenol diazonium salts. For these substitution patterns the methoxy-substituted derivatives are superior.

Probing occurrence of phenylpropanoids in Morinda citrifolia in relation to foliar diseases.

PubMed

Mandal, Sudhamoy; Rath, Chiranjibi; Gupta, Chandan Kumar; Nath, Vishal; Singh, Hari Shankar

2015-01-01

Accumulation of phenolic compounds in cell walls of different plant organs leading to increased lignification is an early defence response of plants against biotic stress. The aim of this work was to delineate occurrence of cell wall-bound (CWB) phenolic compounds in Morinda citrifolia leaves. Alkaline hydrolysis of the cell wall material of leaf tissues yielded 4-coumaric acid (4-CA) as the major bulk of the phenolic compounds in all Morinda germplasms. Next in line was 4-hydroxybenzoic acid. Other phenolics identified were vanillic acid, 4-hydroxybenzaldehyde, vanillin and ferulic acid. Concentrations of all the CWB phenolics were highest in the germplasm CHN-5, followed by the germplasm CHN-1. Incidentally, these two Morinda germplasms recorded lowest incidence of foliar diseases. Significantly higher amounts of 4-CA in combination with other phenolics may be the reasons for lowest incidence of foliar diseases in CHN-5 and CHN-1 germplasms of M. citrifolia.

Application of plasma electrolysis method for simultaneous phenol and Cr(VI) wastewater degradation using Na2SO4 electrolyte

NASA Astrophysics Data System (ADS)

Harianti, Aulia Rahmi; Saksono, Nelson

2017-11-01

Phenol and Cr (VI) are two types of wastewater known as dangerous and difficult to degrade. Through this study, phenol and Cr (VI) metal wastewater were degraded simultaneously using plasma electrolysis method by reactive species, •OH and H•. The variation of anode depth and position of plasma formation as independent variables correlated with yield of hydroxyl radical, percentage of phenol and Cr (VI) degradation, and specific energy. Within 30 minutes, phenol was degraded to 98.4% and Cr (VI) was degraded to 93.35% with 171.05 kJ/mmol in specific energy, and 174.53 ppm in COD. The optimum condition was obtained in anodic plasma and 1.5 cm in anode depth. The highest degradation percentage of phenol and Cr (VI) were 99.79% and 97.33% achieved during 180 minutes of plasma electrolysis process.

Capillary electrophoretic determination of selected phenolic compounds in humic substances of well waters and fertilizers.

PubMed

Chen, Mei-Ying; Chang, Yan-Zin; Lu, Fung-Jou; Chen, Jian-Lian

2010-01-01

Humic substances (HS) from well waters, fertilizers, and synthetic phenolic polymers were characterized by elemental and UV-VIS spectroscopic analyses. Capillary zone electrophoresis (CZE) with UV absorption detection was used to analyze the lignin-derived phenolic distribution in the degradation residues after alkaline CuO oxidation of HS samples. Eleven phenols with p-acetyl, vanillyl and syringyl substituents were selected to optimize the CZE parameters. For well waters and fertilizers, the content of phenolic fragments was in agreement with the findings of the elemental and spectroscopic measurements. Additionally, parameters derived from the vanillic acid/vanilline, syringyl acid/syringaldehyde, p-hydroxyl/vanillyl and syringyl/vanillyl ratios matched analogous studies on dissolved organic matter from natural waters and on humic acids from terrestrial substances. The amount of phenolic monomer bonded within two synthetic HS polymers was found to be 25.9% protocatechuic acid and 71.3% gallic acid.

Phenol metabolism in the leaves of the olive tree (Olea europaea L.) cv. Picual, Verdial, Arbequina, and Frantoio during ripening.

PubMed

Ortega-García, Francisca; Peragón, Juan

2010-12-08

The kinetic behavior and protein-expression level of phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) have been determined in the leaves of the olive tree (Olea europaea L.) of cv. Picual, Verdial, Arbequina, and Frantoio during fruit ripening. Moreover, the concentration of total phenolic compounds, oleuropein, hydroxytyrosol, and tyrosol has been also determined. This study was carried out in 20-year-old olive trees grown in Jaén (Spain). The concentration of total and specific phenols showed a specific pattern in each cultivar. Frantoio showed the highest phenol concentration followed by Arbequina, Picual, and Verdial. A coordinated response between PAL, PPO, and the concentration of total phenols in the four cultivars was found. Also, specific changes were shown over the course of ripening, indicating a regulation of PAL, PPO, and phenol concentration in the olive-tree leaves during fruit ripening.

Effect of phenolic compounds from pretreated sugarcane bagasse on cellulolytic and hemicellulolytic activities.

PubMed

Michelin, Michele; Ximenes, Eduardo; de Lourdes Teixeira de Moraes Polizeli, Maria; Ladisch, Michael R

2016-01-01

This work shows both cellulases and hemicellulases are inhibited and deactivated by water-soluble and acetone extracted phenolics from sugarcane bagasse pretreated at 10% (w/v) for 30 min in liquid hot water at 180 or 200°C. The dissolved phenolics in vacuum filtrate increased from 1.4 to 2.4 g/L as temperature increased from 180 to 200°C. The suppression of cellulose and hemicellulose hydrolysis by phenolics is dominated by deactivation of the β-glucosidase or β-xylosidase components of cellulase and hemicellulase enzyme by acetone extract at 0.2-0.65 mg phenolics/mg enzyme protein and deactivation of cellulases and hemicellulases by the water soluble components in vacuum filtrate at 0.05-2mg/mg. Inhibition was a function of the type of enzyme and the manner in which the phenolics were extracted from the bagasse. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chemical composition and antibacterial activities of lupin seeds extracts.

PubMed

Lampart-Szczapa, Eleonora; Siger, Aleksander; Trojanowska, Krystyna; Nogala-Kalucka, Małgorzata; Malecka, Maria; Pacholek, Bogdan

2003-10-01

Determination of influence of lupin natural phenolic compounds on antibacterial properties of its seeds was carried out. Raw material were seeds of Lupinus albus, L. luteus, and L. angustifolius. The methods included the determination of the content of proteins, total phenolic compounds, free phenolic acids, and tannins as well as antibacterial properties with ethanol extracts. The content of total phenolic compounds was smaller in testas than in cotyledons and the highest levels are observed in bitter cultivars of Lupinus albus cv. Bac and L. angustifolius cv. Mirela. Lupin tannins mainly occurred in cotyledons of the white lupin, predominantly in the bitter cultivar Bac. Free phenolic acids were mainly found in testas. Only extracts from the testas displayed antibacterial properties, which excludes the possibility of alkaloid influence on the results. The results suggest that inhibition of test bacteria growth depended mainly upon the content of the total phenolic compounds.

Antioxidant capacity and phenolic acids of virgin coconut oil.

PubMed

Marina, A M; Man, Y B Che; Nazimah, S A H; Amin, I

2009-01-01

The antioxidant properties of virgin coconut oil produced through chilling and fermentation were investigated and compared with refined, bleached and deodorized coconut oil. Virgin coconut oil showed better antioxidant capacity than refined, bleached and deodorized coconut oil. The virgin coconut oil produced through the fermentation method had the strongest scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and the highest antioxidant activity based on the beta-carotene-linoleate bleaching method. However, virgin coconut oil obtained through the chilling method had the highest reducing power. The major phenolic acids detected were ferulic acid and p-coumaric acid. Very high correlations were found between the total phenolic content and scavenging activity (r=0.91), and between the total phenolic content and reducing power (r=0.96). There was also a high correlation between total phenolic acids and beta-carotene bleaching activity. The study indicated that the contribution of antioxidant capacity in virgin coconut oil could be due to phenolic compounds.

Effect of Bioprocessing on the In Vitro Colonic Microbial Metabolism of Phenolic Acids from Rye Bran Fortified Breads.

PubMed

Koistinen, Ville M; Nordlund, Emilia; Katina, Kati; Mattila, Ismo; Poutanen, Kaisa; Hanhineva, Kati; Aura, Anna-Marja

2017-03-08

Cereal bran is an important source of dietary fiber and bioactive compounds, such as phenolic acids. We aimed to study the phenolic acid metabolism of native and bioprocessed rye bran fortified refined wheat bread and to elucidate the microbial metabolic route of phenolic acids. After incubation in an in vitro colon model, the metabolites were analyzed using two different methods applying mass spectrometry. While phenolic acids were released more extensively from the bioprocessed bran bread and ferulic acid had consistently higher concentrations in the bread type during fermentation, there were only minor differences in the appearance of microbial metabolites, including the diminished levels of certain phenylacetic acids in the bioprocessed bran. This may be due to rye matrix properties, saturation of ferulic acid metabolism, or a rapid formation of intermediary metabolites left undetected. In addition, we provide expansion to the known metabolic pathways of phenolic acids.

Toxicity and kinetic parameters of the aerobic biodegradation of the phenol and alkylphenols by a mixed culture.

PubMed

Acuña-Argüelles, M E; Olguin-Lora, P; Razo-Flores, E

2003-04-01

A mixed culture aerobically metabolized phenol, cresol isomers (o-,m-,p-), 2-ethylphenol and xylenol isomers (2,5-DMP and 3,4-DMP) as the sole carbon and energy source. This culture had a high tolerance towards phenol with values of maximum degradation rate (Vmax) of 47 microM phenol mg-1 protein h-1 and inhibition substrate constant (Ki) of 10 mM. These kinetic parameters were considerably diminished and the toxicity increased with the alkylphenols. For example with 2,5-xylenol, Vmax and Ki values of 0.8 microM 2,5-xylenol mg-1 protein h-1 and 1.3 mM, respectively, were obtained. The cresols were 5-fold more toxic than phenol, whereas 2-ethylphenol and 3,4-xylenol were 11-fold more toxic, and 2,5-xylenol was 34-fold more toxic than phenol.

Semisynthetic Phenol Derivatives Obtained from Natural Phenols: Antimicrobial Activity and Molecular Properties.

PubMed

Pinheiro, Patrícia Fontes; Menini, Luciana Alves Parreira; Bernardes, Patrícia Campos; Saraiva, Sérgio Henriques; Carneiro, José Walkimar Mesquita; Costa, Adilson Vidal; Arruda, Társila Rodrigues; Lage, Mateus Ribeiro; Gonçalves, Patrícia Martins; Bernardes, Carolina de Oliveira; Alvarenga, Elson Santiago; Menini, Luciano

2018-01-10

Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1 H NMR, 13 C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 μg mL -1 . Most of the tested compounds presented MIC values ≤220 μg mL -1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.

Phenols recovery after steam explosion of Olive Mill Solid Waste and its influence on a subsequent biomethanization process.

PubMed

Serrano, Antonio; Fermoso, Fernando G; Alonso-Fariñas, Bernabé; Rodríguez-Gutierrez, Guillermo; Fernandez-Bolaños, Juan; Borja, Rafael

2017-11-01

A promising source of high added value compounds is the Olive Mill Solid Waste (OMSW). The aim of this research was to evaluate the viability of a biorefinery approach to valorize OMSW through the combination of steam explosion, phenols extraction, and anaerobic digestion. Steam explosion treatment increased the total phenol content in the steam exploited OMSW, which was twice than that the total phenol content in raw OMSW, although some undesirable compounds were also formed. Phenol extraction allowed the recovery of 2098mg hydroxytyrosol per kg of OMSW. Anaerobic digestion allowed the partial stabilization of the different substrates, although it was not improved by the steam explosion treatment. The economic suitability of the proposed biorefinery approach is favorable up to a phenol extract price 90.7% lower than the referenced actual price of 520€/kg. Copyright © 2017 Elsevier Ltd. All rights reserved.

The oxidation of phenol by ferrate(VI) and ferrate(V). A pulse radiolysis and stopped-flow study.

PubMed

Rush, J D; Cyr, J E; Zhao, Z; Bielski, B H

1995-04-01

Potassium ferrate, K2FeO4, is found to oxidize phenol in aqueous solution (5.5 < or = pH < or = 10) by a process which is second order in both reactants; -d[FeVI]/dt=k1[FeVI][phenol], k1 = 10(7)M-1s-1. Product analysis by HPLC showed a mixture of hydroxylated products, principally paraquinone, and biphenols that indicate that oxidation of phenol occurs by both one-electron and two-electron pathways. The two-electron oxidant, producing both para- and ortho-hydroxylated phenols is considered to be ferrate(V) which is itself produced by the initial one-electron reduction of ferrate(VI). The rate of ferrate(V) reaction with phenol was determined by pre-mix stopped flow pulse-radiolysis and found to be k7 = (3.8 +/- 0.4) x 10(5)M-1s-1.

Plant secondary metabolites and gut health: the case for phenolic acids.

PubMed

Russell, Wendy; Duthie, Garry

2011-08-01

Plant-based diets contain a plethora of secondary metabolites that may impact on health and disease prevention. Much attention has been focused on the potential bioactivity and nutritional relevance of several classes of phytochemicals such as flavonoids, carotenoids, phyto-oestrogens and glucosinolates. Less attention has been paid to simple phenolic acids that are widely found in fruit, vegetables, herbs, spices and beverages. Daily intakes may exceed 100 mg. In addition, bacteria in the gut can perform reactions that transform more complex plant phenolics such as anthocyanins, procyanidins, flavanones, flavonols, tannins and isoflavones into simple phenolic metabolites. The colon is thus a rich source of potentially active phenolic acids that may impact both locally and systemically on gut health. Both the small and large intestine (colon) contain absorption sites for phenolic acids but low post-prandial concentrations in plasma indicate minimal absorption early in the gastrointestinal tract and/or rapid hepatic metabolism and excretion. Therefore, any bioactivity that contributes to gut health may predominantly occur in the colon. Several phenolic acids affect the expression and activity of enzymes involved in the production of inflammatory mediators of pathways thought to be important in the development of gut disorders including colon cancer. However, at present, we remain largely ignorant as to which of these compounds are beneficial to gut health. Until we can elucidate which pro-inflammatory and potentially carcinogenetic changes in gene expression can be moderated by simple phenolic acids, it is not possible to recommend specific plant-based foods rich in particular phenolics to optimise gut health.

Lethal and teratogenic effects of phenol on Bufo arenarum embryos.

PubMed

Paisio, Cintia Elizabeth; Agostini, Elizabeth; González, Paola Solange; Bertuzzi, Mabel Lucía

2009-08-15

Phenol and their derivatives are used in several industries and they have a high potential toxicity for animal and plant species. They were found in variable concentrations, as high as 1000 mg/L, in industrial wastewater and, they are often discharged into the environment. Amphibian embryos are useful indicators of environmental pollution. However, to our knowledge, there are not studies focussed on the toxic effects of phenol on Bufo arenarum, which is an anuran widely distributed in South America. Therefore, the effect of phenol on the survival and morphogenesis of these amphibian embryos was evaluated by means of AMPHITOX test. Embryos at 25 stage of development (acute test) and embryos at 2-4 blastomers stage (early life stage test), were exposed to phenol solutions in concentrations ranging from 25 to 250 mg/L, which were frequently found in the environment. Mortality and malformations were registered each 24h. LC(50), LC(99), NOEC, TC(50) and TI(50) values were 183.70, 250, 60, 113 mg/L and 1.62, respectively, at 96 h of treatment. Mortality and the percentage of malformations increased with increasing phenol concentrations. Teratogenic effects more frequently produced by phenol were: axial flexure, persistent yolk plug and different abnormalities which caused death of blastulae. Moreover, other malformations were registered, such as irregular form, acephalism, edema, axial shortening and underdevelopment of gills, among others. Larvae of B. arenarum, at early embryonic stages (blastulae), showed higher sensitivity to phenol than tadpoles at stage 25. Results confirm high susceptibility of amphibians to phenol and that environmental concentrations of this pollutant might be harmful to these populations.

Phenol biodegradation by immobilized Pseudomonas putida FNCC-0071 cells in alginate beads

NASA Astrophysics Data System (ADS)

Hakim, Lukman Nul; Rochmadi, Sutijan

2017-06-01

Phenol is one of industrial liquid waste which is harmful to the environment, so it must be degraded. It can be degraded by immobilized Pseudomonas putida FNCC-0071 cells. It needs the kinetics and mass transfer data to design this process which can be estimated by the proposed dynamic model in this study. This model involves simultaneous diffusion and reaction in the alginate bead and liquid bulk. The preliminary stage of phenol biodegradation process was acclimatization cells. This is the stage where cells were acclimated to phenol as carbon source (substrate). Then the acclimated cells were immobilized in alginate beads by extrusion method. The variation of the initial phenol concentration in the solution is 350 to 850 ppm where 60 g alginate bead contained by cells loaded into its solution in reactor batch, so then biodegradation occurs. In this study, the average radius of alginate bead was 0.152 cm. The occurred kinetic reaction process can be explained by Blanch kinetic model with the decreasing of parameter μmax' while the increasing values of initial phenol concentration in the same time, but the parameters KM, KM', and kt were increasing by the rising values of initial phenol concentration. The value of the parameter β is almost zero. Effective diffusivity of phenol and cells are 1.11 × 10-5±4.5% cm2 s-1 and 1.39 × 10-7± 0.04% cm2 s-1. The partition coefficient of phenol and cells are 0.39 ± 15% and 2.22 ± 18%.

Rapid estimation of the oxidative activities of individual phenolics in crude plant extracts.

PubMed

Vihakas, Matti; Pälijärvi, Maija; Karonen, Maarit; Roininen, Heikki; Salminen, Juha-Pekka

2014-07-01

Previous studies of purified phenolic compounds have revealed that some phenolics, especially ellagitannins, can autoxidise under alkaline conditions, which predominate in the midgut of lepidopteran larvae. To facilitate screening for the pro-oxidant activities of all types of phenolic compounds from crude plant extracts, we developed a method that combined our recent spectrophotometric bioactivity method with an additional chromatographic step via UPLC-DAD-MS. This method allowed us to estimate the total pro-oxidant capacities of crude extracts from 12 plant species and to identify the individual phenolic compounds that were responsible for the detected activities. It was found that the pro-oxidant capacities of the plant species (i.e., the concentrations of the easily-oxidised phenolics) varied from 0 to 57 mg/g dry wt, representing from 0% to 46% of the total phenolics from different species. UPLC-DAD-MS analysis revealed that most flavonol and flavone glycosides were only slightly affected by alkaline conditions, thus indicating their low pro-oxidant activity. Interestingly, myricetin-type compounds differed from the other flavonoids, as their concentrations decreased strongly due to alkaline incubation. The same effect was detected for hydrolysable tannins and prodelphinidins, suggesting that a pyrogallol sub-structure could be a key structural component that partially explains their easy oxidation at high pH. Other types of phenolic compounds, such as hydroxycinnamic acids, were relatively active, as well. These findings demonstrate that this method displays the potential to identify most of the active and inactive pro-oxidant phenolic compounds in various plant species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Spatial distribution and ecological risk assessment of phthalic acid esters and phenols in surface sediment from urban rivers in Northeast China.

PubMed

Li, Bin; Liu, Ruixia; Gao, Hongjie; Tan, Ruijie; Zeng, Ping; Song, Yonghui

2016-12-01

Concentration and spatial distribution of six phthalic acid esters (PAEs) and eight phenols in sediments of urban rivers, namely the Xi River (XR) and Pu River (PR) in Shenyang city, Northeast China were investigated and the ecological risk of these target pollutants was assessed based on the risk quotient (RQ) approach. Target PAEs and phenols were detected in most of sediment samples collected from the XR and PR. The concentrations of total PAEs in sediments varied from 22.4 to 369 μg/g dw in the XR and 3.71-46.9 μg/g dw in the PR. The levels of phenols ranged from 2.72 to 106 μg/g dw in the XR and 0.811-25.0 μg/g dw in the PR, respectively. The dominant pollutants in both XR and PR were DEHP, phenol and 4-methylphnol. The sampling locations XR1-3 in the XR suffered severe contamination from PAEs and phenols. The sites PR1 and PR6 were heavily polluted by phenols and PAEs, respectively. Almost all target PAEs and phenolic compounds in sediment of the XR exhibited medium or high ecological risk to organisms and the ecological risk in the PR mainly originated from PEAs, phenol and 4-methylphenol. These results would provide guidance for individual pollutant control and indicate that it is imperative to take some effective measures to reduce the pollution of those contaminants. Copyright © 2016 Elsevier Ltd. All rights reserved.

ABTS as an Electron Shuttle to Enhance the Oxidation Kinetics of Substituted Phenols by Aqueous Permanganate.

PubMed

Song, Yang; Jiang, Jin; Ma, Jun; Pang, Su-Yan; Liu, Yong-Ze; Yang, Yi; Luo, Cong-Wei; Zhang, Jian-Qiao; Gu, Jia; Qin, Wen

2015-10-06

In this study, it was, interestingly, found that 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonate (ABTS), a widely used electron shuttle, could greatly accelerate the oxidation of substituted phenols by potassium permanganate (Mn(VII)) in aqueous solutions at pH 5-9. This was attributed to the fact that these substituted phenols could be readily oxidized by the stable radical cation (ABTS(•+)), which was quickly produced from the oxidation of ABTS by Mn(VII). The reaction of Mn(VII) with ABTS exhibited second-order kinetics, with stoichiometries of ∼5:1 at pH 5-6 and ∼3:1 at pH 7-9, and the rate constants varied negligibly from pH 5 to 9 (k = (9.44 ± 0.21) × 10(4) M(-1) s(-1)). Comparatively, the reaction of ABTS(•+) with phenol showed biphasic kinetics. The second-order rate constants for the reactions of ABTS(•+) with substituted phenols obtained in the initial phase were strongly affected by pH, and they were several orders of magnitude higher than those for the reactions of Mn(VII) with substituted phenols at each pH. Good Hammett-type correlations were found for the reactions of ABTS(•+) with undissociated (log(k) = 2.82-4.31σ) and dissociated phenols (log(k) = 7.29-5.90σ). The stoichiometries of (2.2 ± 0.06):1 (ABTS(•+) in excess) and (1.38 ± 0.18):1 (phenol in excess) were achieved in the reaction of ABTS(•+) with phenol, but they exhibited no pH dependency.

Quorum Quenching and Microbial Control through Phenolic Extract of Eugenia Uniflora Fruits.

PubMed

Rodrigues, Adeline Conceição; Zola, Flávia Guimarães; Ávila Oliveira, Brígida D'; Sacramento, Nayara Thais Barbosa; da Silva, Elis Regina; Bertoldi, Michele Corrêa; Taylor, Jason Guy; Pinto, Uelinton Manoel

2016-10-01

We describe the characterization of the centesimal composition, mineral and phenolic content of Eugenia uniflora fruit and the determination of the antioxidant, antimicrobial and quorum quenching activities of the pulp phenolic extract. Centesimal composition was determined according to standard methods; trace elements were measured by total reflection X-ray fluorescence spectroscopy. The phenolic compounds were extracted by solid-phase chromatography and quantified by spectrophotometry. Antioxidant activity was determined by using 3 different methods. Antimicrobial activity was evaluated against a panel of foodborne microorganisms and antiquorum sensing activity in Chromobacterium violaceum was performed by measuring inhibition of quorum sensing dependent violacein production. The centesimal composition (per 100 g of pulp) was as follows: protein 3.68 ± 0.21 g, lipids 0.02 ± 0.03 g, carbohydrates 10.31 g and fiber 2.06 g. Trace elements (mg/g of pulp) were determined as: K 0.90, Ca 3.36, Fe 0.60, Zn 0.17, Cl 0.56, Cr 0.06, Ni 0.04, and Cu 0.07. The pulp is a source of phenolic compounds and presents antioxidant activity similar to other berries. The fruit phenolic extract inhibited all tested bacteria. We also found that the fruit phenolic extract at low subinhibitory concentrations inhibited up to 96% of violacein production in C. violaceum, likely due to the fruit's phenolic content. This study shows the contribution of E. uniflora phenolic compounds to the antioxidant, antimicrobial and the newly discovered quorum quenching activity, all of which could be used by the food and pharmaceutical industries to develop new functional products. © 2016 Institute of Food Technologists®.

Structure Properties and Mechanisms of Action of Naturally Originated Phenolic Acids and Their Derivatives against Human Viral Infections.

PubMed

Wu, Yi-Hang; Zhang, Bing-Yi; Qiu, Li-Peng; Guan, Rong-Fa; Ye, Zi-Hong; Yu, Xiao-Ping

2017-01-01

A great effort has been made to develop efficacious antiviral drugs, but many viral infections are still lack of efficient antiviral therapies so far. The related exploration of natural products to fight viruses has been raised in recent years. Natural compounds with structural diversity and complexity offer a great chance to find new antiviral agents. Particularly, phenolic acids have attracted considerable attention owing to their potent antiviral abilities and unique mechanisms. The aim of this review is to report new discoveries and updates pertaining to antiviral phenolic acids. The relevant references on natural phenolic acids were searched. The antiviral phenolic acids were classified according to their structural properties and antiviral types. Meanwhile, the antiviral characteristics and structure-activity relationships of phenolic acids and their derivatives were summarized. The review finds that natural phenolic acids and their derivatives possessed potent inhibitory effects on multiple virus in humans such as human immunodeficiency virus, hepatitis C virus, hepatitis B virus, herpes simplex virus, influenza virus and respiratory syncytial virus. In particular, caffeic acid/gallic acid and their derivatives exhibited outstanding antiviral properties by a variety of modes of action. Naturally derived phenolic acids especially caffeic acid/gallic acid and their derivatives may be regarded as novel promising antiviral leads or candidates. Additionally, scarcely any of these compounds has been used as antiviral treatment in clinical practice. Therefore, these phenolic acids with diverse skeletons and mechanisms provide us an excellent resource for finding novel antiviral drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Theoretical and experimental evidence of the photonitration pathway of phenol and 4-chlorophenol: a mechanistic study of environmental significance.

PubMed

Bedini, Andrea; Maurino, Valter; Minero, Claudio; Vione, Davide

2012-02-01

Light-induced nitration pathways of phenols are important processes for the transformation of pesticide-derived secondary pollutants into toxic derivatives in surface waters and for the formation of phytotoxic compounds in the atmosphere. Moreover, phenols can be used as ˙NO(2) probes in irradiated aqueous solutions. This paper shows that the nitration of 4-chlorophenol (4CP) into 2-nitro-4-chlorophenol (NCP) in the presence of irradiated nitrate and nitrite in aqueous solution involves the radical ˙NO(2). The experimental data allow exclusion of an alternative nitration pathway by ˙OH + ˙NO(2). Quantum mechanical calculations suggest that the nitration of both phenol and 4CP involves, as a first pathway, the abstraction of the phenolic hydrogen by ˙NO(2), which yields HNO(2) and the corresponding phenoxy radical. Reaction of phenoxyl with another ˙NO(2) follows to finally produce the corresponding nitrated phenol. Such a pathway also correctly predicts that 4CP undergoes nitration more easily than phenol, because the ring Cl atom increases the acidity of the phenolic hydrogen of 4CP. This favours the H-abstraction process to give the corresponding phenoxy radical. In contrast, an alternative nitration pathway that involves ˙NO(2) addition to the ring followed by H-abstraction by oxygen (or by ˙NO(2) or ˙OH) is energetically unfavoured and erroneously predicts faster nitration for phenol than for 4CP. This journal is © The Royal Society of Chemistry and Owner Societies 2012

Method for making adhesive from biomass

DOEpatents

Russell, J.A.; Riemath, W.F.

1984-03-30

A method is described for making adhesive from biomass. A liquefaction oil is prepared from lignin-bearing plant material and a phenolic fraction is extracted therefrom. The phenolic fraction is reacted with formaldehyde to yield a phenol-formaldehyde resin. 2 figures.

HPLC profiling of phenolics in diverse potato genotypes

USDA-ARS?s Scientific Manuscript database

Methanolic extracts of potatoes from over fifty genotypes representing cultivars, breeding lines, primitive germplasm and wild species were analyzed for phenolic content and hydrophilic antioxidant capacity. Total phenolics were measured using the Folin-Ciocalteau method, antioxidant capacity using ...

Factors Affecting the Extraction of Intact Ribonucleic Acid from Plant Tissues Containing Interfering Phenolic Compounds

PubMed Central

Newbury, H. John; Possingham, John V.

1977-01-01

Using conventional methods it is impossible to extract RNA as uncomplexed intact molecules from the leaves of grapevines (Vitis vinifera L.) and from a number of woody perennial species that contain high levels of reactive phenolic compounds. A procedure involving the use of high concentrations of the chaotropic agent sodium perchlorate prevents the binding of phenolic compounds to RNA during extraction. Analyses of the phenolics present in plant tissues used in these experiments indicate that there is a poor correlation between the total phenolic content and the complexing of RNA. However, qualitative analyses suggest that proanthocyanidins are involved in the tanning of RNA during conventional extractions. PMID:16660134

Growth kinetics of Bacillus stearothermophilus BR219

DOE Office of Scientific and Technical Information (OSTI.GOV)

Worden, R.M.; Subramanian, R.; Bly, M.J.

1991-12-31

Bacillus stearothermophilus BR219, a phenol-resistant thermophile, can convert phenol to the specialty chemical catechol. The growth kinetics of this organism were studied in batch, continuous, and immobilized-cell culture. Batch growth was insensitive to pH between 6.0 and 8.0, but little growth occurred at 5.5. In continuous culture on a dilute medium supplemented with 10 mM phenol, several steady states were achieved between dilution rates of 0.25 and 1.3 h{sup -1}. Phenol degradation was found to be uncoupled from growth. Immobilized cells grew rapidly in a rich medium, but cell viability plummeted following a switch to a dilute medium supplemented withmore » 5 mM phenol.« less

Peroxidase-catalyzed removal of phenols from a petroleum refinery wastewater.

PubMed

Wagner, M; Nicell, J A

2001-01-01

The phenol content of a petroleum refinery wastewater was reduced below the discharge limit following treatment with horseradish peroxidase and H2O2. Approximately 58% of COD, 78% of BOD5, and 95% of toxicity were removed along with the phenols. As a result of treatment, phenols were transformed into less biodegradable compounds which could be removed by subsequent coagulation and precipitation. Optimization of the peroxide concentration led to 20% enzyme savings. The use of PEG and chitosan as protective additives resulted in 4 and 25-fold reductions in enzyme requirements, respectively. Phenol removal did not appear to be adversely affected by the presence of other hydrocarbons that are frequently present in refinery wastewaters.

Surface-modified TiO2 powders with phenol derivatives: A comparative DFT and experimental study

NASA Astrophysics Data System (ADS)

Sredojević, Dušan N.; Kovač, Tijana; Džunuzović, Enis; Ðorđević, Vesna; Grgur, Branimir N.; Nedeljković, Jovan M.

2017-10-01

The charge transfer complex formation between TiO2 powder and variety of phenol derivatives (phenol, 4-nitrophenol, 4-bromophenol, 4-tert-butylphenol, hydroquinone) was achieved. The red-shift of optical absorption was observed upon surface modification of TiO2 powders with phenol derivatives. The influence of substituent functional groups in para position on the optical band gap and conduction band edge of inorganic/organic hybrids was studied using reflection spectroscopy and cyclic voltammetry. The experimental findings were supported by density functional theory calculations. The measured reflection spectra of surface-modified TiO2 powders with phenol derivatives were compared with calculated electronic excitation spectra of corresponding model systems.

The influence of beverage composition on delivery of phenolic compounds from coffee and tea.

PubMed

Ferruzzi, Mario G

2010-04-26

Epidemiological data suggest that consumption of coffee and tea is associated with a reduced risk of several chronic and degenerative diseases including cardiovascular disorders, diabetes, obesity and neurodegenerative disorders. Both coffee and tea are a rich source of phenolic compounds including chlorogenic acids in coffee; and flavan-3-ols as well as complex theaflavins and thearubigens in tea. Coffee and tea are two of the most commonly consumed beverages in the world and thus represent a significant opportunity to positively affect disease risk and outcomes globally. Central to this opportunity is a need to better understand factors that may affect the bioavailability of specific phenolic components from coffee and tea based beverages. An overview of the phenolic composition of coffee and tea is discussed in the context of how processing and composition might influence phenolic profiles and bioavailability of individual phenolic components. Specifically, the impact of beverage formulation, the extent and type of processing and the influence of digestion on stability, bioavailability and metabolism of bioactive phenolics from tea and coffee are discussed. The impact of co-formulation with ascorbic acid and other phytochemicals are discussed as strategies to improve absorption of these health promoting phytochemicals. A better understanding of how the beverage composition impacts phenolic profiles and their bioavailability is critical to development of beverage products designed to deliver specific health benefits. Copyright 2010 Elsevier Inc. All rights reserved.

Phenolic root exudate and tissue compounds vary widely among temperate forest tree species and have contrasting effects on soil microbial respiration.

PubMed

Zwetsloot, Marie J; Kessler, André; Bauerle, Taryn L

2018-04-01

Root-soil interactions fundamentally affect the terrestrial carbon (C) cycle and thereby ecosystem feedbacks to climate change. This study addressed the question of whether the secondary metabolism of different temperate forest tree species can affect soil microbial respiration. We hypothesized that phenolics can both increase and decrease respiration depending on their function as food source, mobilizer of other soil resources, signaling compound, or toxin. We analyzed the phenolic compounds from root exudates and root tissue extracts of six tree species grown in a glasshouse using high-performance liquid chromatography. We then tested the effect of individual phenolic compounds, representing the major identified phenylpropanoid compound classes, on microbial respiration through a 5-d soil incubation. Phenolic root profiles were highly species-specific. Of the eight classes identified, flavonoids were the most abundant, with flavanols being the predominating sub-class. Phenolic effects on microbial respiration ranged from a 26% decrease to a 46% increase, with reduced respiration occurring in the presence of compounds possessing a catechol ring. Tree species variation in root phenolic composition influences the magnitude and direction of root effects on microbial respiration. Our data support the hypothesis that functional group rather than biosynthetic class determines the root phenolic effect on soil C cycling. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Phenolic compound concentration and antioxidant activities of edible and medicinal mushrooms from Korea.

PubMed

Kim, Min-Young; Seguin, Philippe; Ahn, Joung-Kuk; Kim, Jong-Jin; Chun, Se-Chul; Kim, Eun-Hye; Seo, Su-Hyun; Kang, Eun-Young; Kim, Sun-Lim; Park, Yool-Jin; Ro, Hee-Myong; Chung, Ill-Min

2008-08-27

A study was conducted to determine the content of phenolic compounds and the antioxidative activity of five edible and five medicinal mushrooms commonly cultivated in Korea. Phenolic compounds were analyzed using high performance liquid chromatography, and antioxidant activity was evaluated by 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide dismutase activity. A total of 28 phenolic compounds were detected in the mushrooms studied. The average total concentration of phenolic compounds was 326 microg/g, the average being of 174 microg/g in edible mushrooms and 477 microg/g in medicinal mushrooms. The average total flavonoids concentration was 49 microg/g, with averages of 22 and 76 microg/g in edible and medicinal mushrooms, respectively. The DPPH radical scavenging activities ranged between 15 (Pleurotus eryngii) and 70% (Ganoderma lucidum) when reaction time was for 1 min. When reaction time was 30 min, the values ranged between 5 (Pleurotus eryngii) and 78% (Agaricus bisporus). The SOD activity averaged 28% among the 10 mushroom species, averages for edible and medicinal mushrooms being comparable. DPPH activities was significantly correlated (p < 0.01) with total content of phenolic compounds in edible mushrooms, while in medicinal mushrooms there was a significant correlation (p < 0.01) between SOD activity and total concentration of phenolic compounds. Numerous significant positive correlations were observed between phenolic compounds detected and antioxidative potential.

Determination of phenolic priority pollutants utilizing permeation sampling method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Guozheng.

1990-01-01

A passive permeation sampling method for the determination of phenolic priority pollutants in water was developed. Phenols in an aqueous solution permeate a polymeric membrane and are collected on a solid adsorbent in a sampling device. Both solvent and thermal desorption techniques were employed to recovery phenolic pollutants collected. In the solvent desorption, phenolic compounds collected on the XAD-7 resin, and then desorbed by acetonitrile. In the thermal desorption, phenolic compounds collected on Tenax-TA were recovered thermally, Separation and quantification is achieved by a SPB-5 capillary column gas chromatography using a flame ionization detector. There are linear relationships between themore » amount of phenolic compounds collected and the products of the exposure times and concentrations over the range from 5 ppb to 20 ppm with precisions no worse than 13%. The permeation rates of the phenolic pollutants depend upon the exposure temperature, solution pH and membrane area. Samples collected can be stored for up to two weeks without loss. This method provides a simple, convenient and inexpensive way for monitoring the time-weighted-average concentration without the use of a pumping system. An automated sampler which combines the permeation and the thermal desorption techniques together was also developed for water sample obtained from grab sampling. The on-line setup provides a high degree of automation. Detection limits at 10 ppb can be achieved using this sampler.« less

Content of insoluble bound phenolics in millets and their contribution to antioxidant capacity.

PubMed

Chandrasekara, Anoma; Shahidi, Fereidoon

2010-06-09

Soluble and insoluble-bound phenolic extracts of several varieties of millet (kodo, finger, foxtail, proso, pearl, and little millets) whole grains were evaluated for their phenolic contents and antioxidative efficacy using trolox equivalent antioxidant capacity (TEAC), reducing power (RP), and beta-carotene-linoleate model system as well as ferrous chelating activity. In addition, ferulic and p-coumaric acids were present in soluble and bound phenolic fractions of millets, and their contents were determined using high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry (MS). Kodo millet had the highest total phenolic content, whereas proso millet possessed the least. All millet varieties showed high antioxidant activities, although the order of their efficacy was assay dependent. HPLC analysis of millet phenolic extracts demonstrated that the bound fractions contained more ferulic and p-coumaric acids compared to their soluble counterparts. The results of this study showed that soluble as well as bound fractions of millet grains are rich sources of phenolic compounds with antioxidant, metal chelating, and reducing power. The potential of whole millets as natural sources of antioxidants depends on the variety used. The importance of the insoluble bound fraction of millet as a source of ferulic acid and p-coumaric acid was established, and their contribution to the total phenolic content must be taken into account in the assessment of the antioxidant activity of millets.

Growth of Trametes versicolor on phenol.

PubMed

Yemendzhiev, H; Gerginova, M; Krastanov, A; Stoilova, I; Alexieva, Z

2008-11-01

Trametes versicolor 1 was shown to grow on phenol as its sole carbon and energy source. The culture growth and degradation ability dependence on culture medium pH value was observed. The optimal pH value of a liquid Czapek salt medium was 6.5. The investigated strain utilized completely 0.5 g/l phenol in 6 days. The dynamics of the phenol degradation process was investigated. The process was characterized by specific growth rate micromax 0.33 h(-1), metabolic coefficient k=4.4, yield coefficient Yx/s=0.23 and rate of degradation Q=0.506 h(-1). The intracellular activities of phenol hydroxylase (0.333 U/mg protein) and cis,cis-muconate lactonizing enzyme (0.41 U/mg protein) were demonstrated for the first time in this fungus. In an attempt to estimate the occurrence of gene sequences in T. versicolor 1 related to phenol degradation pathway a dot blot analysis with total DNA isolated from this strain was performed. Two synthetic oligonucleotides were used as hybridizing probes. One of the probes was homologous to the 5'end of phyA gene coding for phenol hydroxylase in Trichosporon cutaneum ATCC 46490. The other probe was created on the basis of cis,cis-muconate lactonizing enzyme coding gene in T. cutaneum ATCC 58094. The results of these investigations showed that T. versicolor 1 may carry genes similar to those of Trichosporon cutaneum capable to degrade phenol.

Phenol Photocatalytic Degradation by Advanced Oxidation Process under Ultraviolet Radiation Using Titanium Dioxide

PubMed Central

Nickheslat, Ali; Amin, Mohammad Mehdi; Izanloo, Hassan; Fatehizadeh, Ali; Mousavi, Seyed Mohammad

2013-01-01

Background. The main objective of this study was to examine the photocatalytic degradation of phenol from laboratory samples and petrochemical industries wastewater under UV radiation by using nanoparticles of titanium dioxide coated on the inner and outer quartz glass tubes. Method. The first stage of this study was conducted to stabilize the titanium dioxide nanoparticles in anatase crystal phase, using dip-coating sol-gel method on the inner and outer surfaces of quartz glass tubes. The effect of important parameters including initial phenol concentration, TiO2 catalyst dose, duration of UV radiation, pH of solution, and contact time was investigated. Results. In the dip-coat lining stage, the produced nanoparticles with anatase crystalline structure have the average particle size of 30 nm and are uniformly distributed over the tube surface. The removal efficiency of phenol was increased with the descending of the solution pH and initial phenol concentration and rising of the contact time. Conclusion. Results showed that the light easily passes through four layers of coating (about 105 nm). The highest removal efficiency of phenol with photocatalytic UV/TiO2 process was 50% at initial phenol concentration of 30 mg/L, solution pH of 3, and 300 min contact time. The comparison of synthetic solution and petrochemical wastewater showed that at same conditions the phenol removal efficiency was equal. PMID:23710198

Phenolic Profiles and Antioxidant Activity of Lotus Root Varieties.

PubMed

Yi, Yang; Sun, Jie; Xie, Jun; Min, Ting; Wang, Li-Mei; Wang, Hong-Xun

2016-06-30

Lotus root attracts increasing attention mainly because of its phenolic compounds known as natural antioxidants. Its thirteen varieties were systematically analyzed on the content, distribution, composition and antioxidant activity of phenolic compounds for a better understanding of this aquatic vegetable. The respective mean contents of total phenolics in their flesh, peel and nodes were 1.81, 4.30 and 7.35 mg gallic acid equivalents (GAE)/g fresh weight (FW), and those of total flavonoids were 3.35, 7.69 and 15.58 mg rutin equivalents/g FW. The phenolic composition determined by a high-performance liquid chromatography method varied significantly among varieties and parts. The phenolics of flesh were mainly composed of gallocatechin and catechin; those of peel and node were mainly composed of gallocatechin, gallic acid, catechin and epicatechin. The antioxidant activities of phenolic extracts in increasing order were flesh, peel and node; their mean concentrations for 50% inhibition of 2,2-diphenyl-1-picrylhydrazyl radical were 46.00, 26.43 and 21.72 µg GAE/mL, and their mean values representing ferric reducing antioxidant power were 75.91, 87.66 and 100.43 µg Trolox equivalents/100 µg GAE, respectively. "Zoumayang", "Baheou", "No. 5 elian" and "Guixi Fuou" were the hierarchically clustered varieties with relatively higher phenolic content and stronger antioxidant activity as compared with the others. Especially, their nodes and peels are promising sources of antioxidants for human nutrition.

Antioxidant activity, phenolic-flavonoid content and high-performance liquid chromatography profiling of three different variants of Syzygium cumini seeds: A comparative study.

PubMed

Priya, Syama Hari; Prakasan, Nisha; Purushothaman, Jayamurthy

2017-01-01

The medicinally important phytochemicals present in Syzygium cumini seeds probably accounts for its wide use in traditional systems of medicines in India, like Ayurveda, Unani, and Siddha. The aim of the study was to determine the antioxidant potential of three different geographical variants of S. cumini seeds and to compare the phenolic profiling to know the effect of geographical variation in phenolic composition. Total phenolic and flavonoid content of S. cumini seeds were analyzed. Antioxidant activities in terms of 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), nitric oxide and superoxide radical scavenging assays were performed. The most active fractions were subjected to high-performance liquid chromatography (HPLC) profiling to identify the phenolic composition. Among all the fractions, 70% methanol fraction of S. cumini seed showed significant antioxidant potential. There existed a linear correlation between phenolic content and antioxidant activity. HPLC profiling of 70% methanol (ME) fractions of all the variants revealed the presence of phenolic compounds with high concentrations of ellagic acid and gallic acid. The differences in phenolic concentration due to geographical changes might be the reason for higher antioxidant potential showed by 70% ME of Trivandrum variant. 70% methanolic fraction of S. cumini can act as a novel source of natural antioxidant.

Optimization of pressurized liquid extraction by response surface methodology of Goji berry (Lycium barbarum L.) phenolic bioactive compounds.

PubMed

Tripodo, Giusy; Ibáñez, Elena; Cifuentes, Alejandro; Gilbert-López, Bienvenida; Fanali, Chiara

2018-01-03

Pressurized liquid extraction (PLE) has been used for the first time in this work to extract phenolic compounds from Goji berries according to a multilevel factorial design using response surface methodology. The global yield (% w/dw, weight/dry-weight), total phenolic content (TPC), total flavonoid (TF) and antioxidant activity (determined via ABTS assay, expressed as TEAC value) were used as response variables to study the effects of temperature (50-180°C) and green solvent composition (mixtures of ethanol/water). Phenolic compounds characterization was performed by high performance liquid chromatography-diode array detector-tandem mass spectrometry (HPLC-DAD-MS/MS). The optimum PLE conditions predicted by the model were as follows: 180°C and 86% ethanol in water with a good desirability value of 0.815. The predicted conditions were confirmed experimentally and once the experimental design was validated for commercial fruit samples, the PLE extraction of phenolic compounds from three different varieties of fruit samples (Selvatico mongolo, Bigol, and Polonia) was performed. Nine phenolic compounds were tentatively identified in these extracts, including phenolic acids and their derivatives, and flavonols. The optimized PLE conditions were compared to a conventional solid-liquid extraction, demonstrating that PLE is a useful alternative to extract phenolic compounds from Goji berry. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Protective Effect of Whole Honey and Phenolic Extract on Oxidative DNA Damage in Mice Lymphocytes Using Comet Assay.

PubMed

Cheng, Ni; Wang, Yuan; Cao, Wei

2017-12-01

In this study, the antioxidant activity and the protective effect against hydrogen peroxide-induced DNA damage were assessed for five honeys of different botanical origin. Seven phenolic acids were detected in the honey samples. Ferulic acid was the most abundant phenolic acid detected in longan honey, jujube honey and buckwheat honey. Ellagic acid, p-hydroxybenzoic acid and protocatechuic acid were the main phenolic acids detected in vitex honey. Of all honey samples tested, the highest total phenolic content and antioxidant activity were found in buckwheat honey, whereas the lowest total phenolic content and antioxidant activity were found in locust honey. Treatment with hydrogen peroxide induced a 62% increase in tail DNA in mice lymphocytes, and all studied honeys significantly inhibited this effect (P < 0.05). The buckwheat honey with higher antioxidant capability also exhibited super protective effect than others. Phenolic extracts of honey displayed greater protective effects than whole honey in comet assay. The hydrogen peroxide-generated increase in 8-hydroxy-2-deoxyguanosine (8-OHdG) was effectively inhibited by the honeys studied (P < 0.05). Moreover, a dose-effect relationship between honey concentration and its protective effect was clearly observed in this study. It can be deduced that phenolic acids of honey can penetrate into lymphocytes and protect DNA from oxidative damage by scavenging hydrogen peroxide and/or chelating ferrous ions.

High-resolution mass spectrometry to evaluate the influence of cross-breeding segregating populations on the phenolic profile of virgin olive oils.

PubMed

Sánchez de Medina, Verónica; Calderón-Santiago, Mónica; El Riachy, Milad; Priego-Capote, Feliciano; Luque de Castro, María Dolores

2014-12-01

The growing demand for high-quality virgin olive oils (VOOs) has increased the interest in olive breeding programs. Cross-breeding is considered, within these programs, the best strategy to generate new cultivars as an attempt to improve the present cultivars. In this research, the phenolic profile of VOOs from target crosses (Arbequina × Arbosana, Picual × Koroneiki and Sikitita × Arbosana) and their corresponding genitors (Arbequina, Arbosana, Koroneiki, Picual and Sikitita) has been evaluated using a targeted metabolomics approach. The phenolic profiles were obtained by liquid chromatographic-hybrid quadrupole time-of-flight mass spectrometric targeted analysis of 37 phenols or compounds involved in the main pathways for their biosynthesis. Statistical multivariate analysis by principal component analysis was applied to study the influence of genotype on phenol composition. Phenolic compounds with the highest contribution to explain the observed variability associated to genotype were identified through fold change algorithms (cut-off > 2.0) and t-test analysis. A total of nine phenols (viz. quercetin, ligstroside aglycon (p-HPEA-EA), demethyl oleuropein aglycon, oleuropein aglycon (3,4-DHPEA-EA), hydroxypinoresinol, hydroxytyrosol and phenolic acids such as p-coumaric acid, ferulic acid and protocatechuic acid) contributed to explain the observed variability with 99% confidence (P<0.01). © 2014 Society of Chemical Industry.

Degradation of phenol via phenylphosphate and carboxylation to 4-hydroxybenzoate by a newly isolated strain of the sulfate-reducing bacterium Desulfobacterium anilini.

PubMed

Ahn, Young-Beom; Chae, Jong-Chan; Zylstra, Gerben J; Häggblom, Max M

2009-07-01

A sulfate-reducing phenol-degrading bacterium, strain AK1, was isolated from a 2-bromophenol-utilizing sulfidogenic estuarine sediment enrichment culture. On the basis of phylogenetic analysis of the 16S rRNA gene and DNA homology, strain AK1 is most closely related to Desulfobacterium anilini strain Ani1 (= DSM 4660(T)). In addition to phenol, this organism degrades a variety of other aromatic compounds, including benzoate, 2-hydroxybenzoate, 4-hydroxybenzoate, 4-hydroxyphenylacetate, 2-aminobenzoate, 2-fluorophenol, and 2-fluorobenzoate, but it does not degrade aniline, 3-hydroxybenzoate, 4-cyanophenol, 2,4-dihydroxybenzoate, monohalogenated phenols, or monohalogenated benzoates. Growth with sulfate as an electron acceptor occurred with acetate and pyruvate but not with citrate, propionate, butyrate, lactate, glucose, or succinate. Strain AK1 is able to use sulfate, sulfite, and thiosulfate as electron acceptors. A putative phenylphosphate synthase gene responsible for anaerobic phenol degradation was identified in strain AK1. In phenol-grown cultures inducible expression of the ppsA gene was verified by reverse transcriptase PCR, and 4-hydroxybenzoate was detected as an intermediate. These results suggest that the pathway for anaerobic degradation of phenol in D. anilini strain AK1 proceeds via phosphorylation of phenol to phenylphosphate, followed by carboxylation to 4-hydroxybenzoate. The details concerning such reaction pathways in sulfidogenic bacteria have not been characterized previously.

Development of molecularly imprinted polymer in porous film format for binding of phenol and alkylphenols from water.

PubMed

Gryshchenko, Andriy O; Bottaro, Christina S

2014-01-20

Molecularly imprinted polymers (MIPs) were fabricated on glass slides with a "sandwich" technique giving ~20 µm thick films. Methanol/water as a solvent, and polyethyleneglycol and polyvinylacetate as solvent modifiers, were used to give a porous morphology, which was studied with scanning electron microscopy and gravimetric analysis. Various MIPs were synthesized through non-covalent imprinting with phenol as the template; itaconic acid, 4-vinylpyridine, and styrene as monomers; ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, and pentaerythritol triacrylate (PETA) as cross-linkers. Binding and imprinting properties of the MIPs were evaluated based on phenol adsorption isotherms. Since phenol has only one weakly acidic hydroxyl group and lacks unique structural characteristics necessary for binding specificity, the preparation of selective MIPs was challenging. The recognition of phenol via hydrogen bonding is suppressed in water, while hydrophobic interactions, though promoted, are not specific enough for highly-selective phenol recognition. Nevertheless, the styrene-PETA MIP gave modest imprinting effects, which were higher at lower concentrations (Imprinting Factor (IF) = 1.16 at 0.5 mg·L(-1)). The isotherm was of a Freundlich type over 0.1-40 mg·L(-1) and there was broad cross-reactivity towards other structurally similar phenols. This shows that phenol MIPs or simple adsorbents can be developed based on styrene for hydrophobic binding, and PETA to form a tighter, hydrophilic network.

Quantitative studies on structure-DPPH• scavenging activity relationships of food phenolic acids.

PubMed

Jing, Pu; Zhao, Shu-Juan; Jian, Wen-Jie; Qian, Bing-Jun; Dong, Ying; Pang, Jie

2012-11-01

Phenolic acids are potent antioxidants, yet the quantitative structure-activity relationships of phenolic acids remain unclear. The purpose of this study was to establish 3D-QSAR models able to predict phenolic acids with high DPPH• scavenging activity and understand their structure-activity relationships. The model has been established by using a training set of compounds with cross-validated q2 = 0.638/0.855, non-cross-validated r2 = 0.984/0.986, standard error of estimate = 0.236/0.216, and F = 139.126/208.320 for the best CoMFA/CoMSIA models. The predictive ability of the models was validated with the correlation coefficient r2(pred) = 0.971/0.996 (>0.6) for each model. Additionally, the contour map results suggested that structural characteristics of phenolics acids favorable for the high DPPH• scavenging activity might include: (1) bulky and/or electron-donating substituent groups on the phenol ring; (2) electron-donating groups at the meta-position and/or hydrophobic groups at the meta-/ortho-position; (3) hydrogen-bond donor/electron-donating groups at the ortho-position. The results have been confirmed based on structural analyses of phenolic acids and their DPPH• scavenging data from eight recent publications. The findings may provide deeper insight into the antioxidant mechanisms and provide useful information for selecting phenolic acids for free radical scavenging properties.

Water-deficit and fungal infection can differentially affect the production of different classes of defense compounds in two host pines of mountain pine beetle.

PubMed

Erbilgin, Nadir; Cale, Jonathan A; Lusebrink, Inka; Najar, Ahmed; Klutsch, Jennifer G; Sherwood, Patrick; Enrico Bonello, Pierluigi; Evenden, Maya L

2017-03-01

Bark beetles are important agents of tree mortality in conifer forests and their interaction with trees is influenced by host defense chemicals, such as monoterpenes and phenolics. Since mountain pine beetle (Dendroctonus ponderosae Hopkins) has expanded its host range from lodgepole pine (Pinus contorta Doug. ex Loud. (var. latifolia Engelm.))-dominated forests to the novel jack pine (Pinus banksiana Lamb.) forests in western Canada, studies investigating the jack pine suitability as a host for this beetle have exclusively focused on monoterpenes, and whether phenolics affect jack pine suitability to mountain pine beetle and its symbiotic fungus Grosmannia clavigera is unknown. We investigated the phenolic and monoterpene composition in phloem and foliage of jack and lodgepole pines, and their subsequent change in response to water deficit and G. clavigera inoculation treatments. In lodgepole pine phloem, water deficit treatment inhibited the accumulation of both the total and richness of phenolics, but had no effect on total monoterpene production or richness. Fungal infection also inhibited the total phenolic production and had no effect on phenolic or monoterpene richness, but increased total monoterpene synthesis by 71%. In jack pine phloem, water deficit treatment reduced phenolic production, but had no effect on phenolic or monoterpene richness or total monoterpenes. Fungal infection did not affect phenolic or monoterpene production. Lesions of both species contained lower phenolics but higher monoterpenes than non-infected phloem in the same tree. In both species, richness of monoterpenes and phenolics was greater in non-infected phloem than in lesions. We conclude that monoterpenes seem to be a critical component of induced defenses against G. clavigera in both jack and lodgepole pines; however, a lack of increased monoterpene response to fungal infection is an important evolutionary factor defining jack pine suitability to the mountain pine beetle invasion in western Canada. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Prenatal Exposure to Environmental Phenols: Concentrations in Amniotic Fluid and Variability in Urinary Concentrations during Pregnancy

PubMed Central

Wolff, Mary S.; Calafat, Antonia M.; Ye, Xiaoyun; Bausell, Rebecca; Meadows, Molly; Stone, Joanne; Slama, Rémy; Engel, Stephanie M.

2013-01-01

Background: Maternal urinary biomarkers are often used to assess fetal exposure to phenols and their precursors. Their effectiveness as a measure of exposure in epidemiological studies depends on their variability during pregnancy and their ability to accurately predict fetal exposure. Objectives: We assessed the relationship between urinary and amniotic fluid concentrations of nine environmental phenols, and the reproducibility of urinary concentrations, among pregnant women. Methods: Seventy-one women referred for amniocentesis were included. Maternal urine was collected at the time of the amniocentesis appointment and on two subsequent occasions. Urine and amniotic fluid were analyzed for 2,4- and 2,5-dichlorophenols, bisphenol A, benzophenone-3, triclosan, and methyl-, ethyl-, propyl-, and butylparabens using online solid phase extraction–high performance liquid chromatography–isotope dilution tandem mass spectrometry. Results: Only benzophenone-3 and propylparaben were detectable in more than half of the amniotic fluid samples; for these phenols, concentrations in amniotic fluid and maternal urine collected on the same day were positively correlated (ρ = 0.53 and 0.32, respectively). Other phenols were detected infrequently in amniotic fluid (e.g., bisphenol A was detected in only two samples). The intraclass correlation coefficients (ICCs) of urinary concentrations in samples from individual women ranged from 0.48 and 0.62 for all phenols except bisphenol A (ICC = 0.11). Conclusion: Amniotic fluid detection frequencies for most phenols were low. The reproducibility of urine measures was poor for bisphenol A, but good for the other phenols. Although a single sample may provide a reasonable estimate of exposure for some phenols, collecting multiple urine samples during pregnancy is an option to reduce exposure measurement error in studies regarding the effects of phenol prenatal exposure on health. Citation: Philippat C, Wolff MS, Calafat AM, Ye X, Bausell R, Meadows M, Stone J, Slama R, Engel SM. 2013. Prenatal exposure to environmental phenols: concentrations in amniotic fluid and variability in urinary concentrations during pregnancy. Environ Health Perspect 121:1225–1231; http://dx.doi.org/10.1289/ehp.1206335 PMID:23942273

Plant phenolics – from field to fork

USDA-ARS?s Scientific Manuscript database

Plant secondary metabolites, such as phenolics, are important to human health and for the organoleptic properties they impart to fresh and processed foods. Consumers judge appearance, taste, and texture when making purchasing decisions. Thorough identification of phenolic compounds is key to discern...

Principal component analysis of phenolic acid spectra

USDA-ARS?s Scientific Manuscript database

Phenolic acids are common plant metabolites that exhibit bioactive properties and have applications in functional food and animal feed formulations. The ultraviolet (UV) and infrared (IR) spectra of four closely related phenolic acid structures were evaluated by principal component analysis (PCA) to...

Effects of fungal degradation on the CuO oxidation products of lignin: A controlled laboratory study

NASA Astrophysics Data System (ADS)

Hedges, John I.; Blanchette, Robert A.; Weliky, Karen; Devol, Allan H.

1988-11-01

Duplicate samples of birch wood were degraded for 0, 4, 8 and 12 weeks by the white-rot fungus, Phlebia tremellosus, and for 12 weeks by 6 other white-rot and brown-rot fungi. P. tremellosus caused progressive weight losses and increased the H/C and O/C of the remnant wood by preferentially degrading the lignin component of the middle lamellae. This fungus increased the absolute (weight loss-corrected) yield of the vanillic acid CuO reaction product above its initial level and exponentially decreased the absolute yields of all other lignin-derived phenols. Total yields of syringyl phenols were decreased 1.5 times as fast as total vanillyl phenol yields. Within both phenol families, aldehyde precursors were degraded faster than precursors of the corresponding ketones, which were obtained in constant proportion to the total phenol yield. Although two other white-rot fungi caused similar lignin compositional trends, a fourth white-rot species, Coriolus versicolor, simultaneously eroded all cell wall components and did not concentrate polysaccharides in the remnant wood. Wood degraded by the three brown-rot fungi exhibited porous cell walls with greatly reduced integrity. The brown-rot fungi also preferentially attacked syringyl structural units, but degraded all phenol precursors at a much slower rate than the white-rotters and did not produce excess vanillic acid. Degradation by P. tremellosus linearly increased the vanillic acid/vanillin ratio, (Ad/Al)v, of the remnant birch wood throughout the 12 week degradation study and exponentially decreased the absolute yields of total vanillyl phenols, total syringyl phenols and the syringyl/vanillyl phenol ratio, S/V. At the highest (Ad/Al)v of 0.50 (12 week samples), total yields of syringyl and vanillyl phenols were decreased by 65% and 80%, respectively, with a resulting reduction of 40% in the original S/V. Many of the diagenetically related compositional trends that have been previously reported for lignins in natural environments can be explained by white-rot fungal degradation.

Plant phenolics and absorption features in vegetation reflectance spectra near 1.66 μm

NASA Astrophysics Data System (ADS)

Kokaly, Raymond F.; Skidmore, Andrew K.

2015-12-01

Past laboratory and field studies have quantified phenolic substances in vegetative matter from reflectance measurements for understanding plant response to herbivores and insect predation. Past remote sensing studies on phenolics have evaluated crop quality and vegetation patterns caused by bedrock geology and associated variations in soil geochemistry. We examined spectra of pure phenolic compounds, common plant biochemical constituents, dry leaves, fresh leaves, and plant canopies for direct evidence of absorption features attributable to plant phenolics. Using spectral feature analysis with continuum removal, we observed that a narrow feature at 1.66 μm is persistent in spectra of manzanita, sumac, red maple, sugar maple, tea, and other species. This feature was consistent with absorption caused by aromatic Csbnd H bonds in the chemical structure of phenolic compounds and non-hydroxylated aromatics. Because of overlapping absorption by water, the feature was weaker in fresh leaf and canopy spectra compared to dry leaf measurements. Simple linear regressions of feature depth and feature area with polyphenol concentration in tea resulted in high correlations and low errors (% phenol by dry weight) at the dry leaf (r2 = 0.95, RMSE = 1.0%, n = 56), fresh leaf (r2 = 0.79, RMSE = 2.1%, n = 56), and canopy (r2 = 0.78, RMSE = 1.0%, n = 13) levels of measurement. Spectra of leaves, needles, and canopies of big sagebrush and evergreens exhibited a weak absorption feature centered near 1.63 μm, short ward of the phenolic compounds, possibly consistent with terpenes. This study demonstrates that subtle variation in vegetation spectra in the shortwave infrared can directly indicate biochemical constituents and be used to quantify them. Phenolics are of lesser abundance compared to the major plant constituents but, nonetheless, have important plant functions and ecological significance. Additional research is needed to advance our understanding of the spectral influences of plant phenolics and terpenes relative to dominant leaf biochemistry (water, chlorophyll, protein/nitrogen, cellulose, and lignin).

Isolation and identification of plant phenolic compounds in birch leaves: Air pollution stress and leaf phenolics

NASA Astrophysics Data System (ADS)

Loponen, Jyrki Mikael

Chromatographic (analytical and preparative HPLC), chemical (hydrolysis) and spectroscopic (UV, 1H NMR, 13C NMR and MS) techniques proved to be suitable tools for the structure identification of plant phenolic compounds. More than 30 individual phenolic compounds were detected and quantified. Detailed information of the structures of individual compounds was determined after isolation from birch leaves. Ten flavonoid glycosides were identified. Two of them, myricetin-3-O-α-L-(acetyl)-rhamnopyranoside and quercetin-3-O-α-L-(4/prime'-O-acetyl)- rhamnopyranoside, have been rarely found in birch leaves. Further, some characterized major phenolics with non- flavonoid structures in our study were 1-O-galloyl- β-D-(2-O-acetyl)-glucopyranose, gallic, chlorogenic, neochlorogenic, cis- and trans-forms of 3- and 5-p-coumaroylquinic acids. The presence of gallotannin group was evidenced by strong positive correlations between concentrations of these gallotannins (preliminary identified by HPLC and UV spectra) and the protein precipitation capacity of extracts. Content of gallotannins decreased with leaf growth and maturation. It is known that concentrations of phenolic compounds regularly increase in slowly growing stressed plants and therefore, it is natural that they are also sensitive to different forms of air pollution. Total content and the contents of some individual phenolics correlated negatively with the distance from the pollution source in our study area. In addition to comparing absolute concentrations of compounds in question, the within-tree correlations or within-tree variations of the relevant compounds between polluted and control areas were an alternative approach. Differences in pairwise correlations between the investigated leaf phenolic compounds indicated the competition between some gallotannins and p-coumaroylquinic acids on the polluted but not on the control site. Air pollution seems to be a stress factor for birch trees associated with accumulation, variability, as well as between-compound correlations of individual phenolics in leaves. Effects of atmospheric stress factors on phenolics with different structures result from the activation of the shikimate pathway.

Phosphate starvation promoted the accumulation of phenolic acids by inducing the key enzyme genes in Salvia miltiorrhiza hairy roots.

PubMed

Liu, Lin; Yang, DongFeng; Liang, TongYao; Zhang, HaiHua; He, ZhiGui; Liang, ZongSuo

2016-09-01

Phosphate starvation increased the production of phenolic acids by inducing the key enzyme genes in a positive feedback pathway in Saliva miltiorrhiza hairy roots. SPX may be involved in this process. Salvia miltiorrhiza is a wildly popular traditional Chinese medicine used for the treatment of coronary heart diseases and inflammation. Phosphate is an essential plant macronutrient that is often deficient, thereby limiting crop yield. In this study, we investigated the effects of phosphate concentration on the biomass and accumulation of phenolic acid in S. miltiorrhiza. Results show that 0.124 mM phosphate was favorable for plant growth. Moreover, 0.0124 mM phosphate was beneficial for the accumulation of phenolic acids, wherein the contents of danshensu, caffeic acid, rosmarinic acid, and salvianolic acid B were, respectively, 2.33-, 1.02-, 1.68-, and 2.17-fold higher than that of the control. By contrast, 12.4 mM phosphate inhibited the accumulation of phenolic acids. The key enzyme genes in the phenolic acid biosynthesis pathway were investigated to elucidate the mechanism of phosphate starvation-induced increase of phenolic acids. The results suggest that phosphate starvation induced the gene expression from the downstream pathway to the upstream pathway, i.e., a feedback phenomenon. In addition, phosphate starvation response gene SPX (SYG1, Pho81, and XPR1) was promoted by phosphate deficiency (0.0124 mM). We inferred that SPX responded to phosphate starvation, which then affected the expression of later responsive key enzyme genes in phenolic acid biosynthesis, resulting in the accumulation of phenolic acids. Our findings provide a resource-saving and environmental protection strategy to increase the yield of active substance in herbal preparations. The relationship between SPX and key enzyme genes and the role they play in phenolic acid biosynthesis during phosphate deficiency need further studies.

Dose-response plasma appearance of coffee chlorogenic and phenolic acids in adults.

PubMed

Renouf, Mathieu; Marmet, Cynthia; Giuffrida, Francesca; Lepage, Mélissa; Barron, Denis; Beaumont, Maurice; Williamson, Gary; Dionisi, Fabiola

2014-02-01

Coffee contains phenolic compounds, mainly chlorogenic acids (CGAs). Even though coffee intake has been associated with some health benefits in epidemiological studies, the bioavailability of coffee phenolics is not fully understood. We performed a dose-response study measuring plasma bioavailability of phenolics after drinking three increasing, but still nutritionally relevant doses of instant pure soluble coffee. The study design was a one treatment (coffee) three-dose randomized cross-over design, with a washout period of 2 wks between visits. CGAs, phenolic acids, and late-appearing metabolites all increased with increasing ingested dose. Hence, the sum of area under the curve was significantly higher for the medium to low dose, and high to medium dose, by 2.23- and 2.38-fold, respectively. CGAs were not well absorbed in their intact form, regardless of the dose. CGA and phenolic acids appeared rapidly in plasma, indicating an early absorption in the gastrointestinal tract. Late-appearing metabolites were the most abundant, regardless of the dose. This study confirmed previous findings about coffee bioavailability but also showed that coffee phenolics appear in a positive dose-response manner in plasma when drank at nutritionally relevant doses. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phenolic contamination in the sand-and-gravel aquifer from a surface impoundment of wood treatment wastes, Pensacola, Florida

USGS Publications Warehouse

Troutman, D.E.; Godsy, E.M.; Goerlitz, D.F.; Ehrlich, G.G.

1984-01-01

Creosote and pentachlorophenol wastewaters discharged to unlined surface impoundments have resulted in groundwater contamination in the vicinity of an industrial site near Pensacola, Florida. Total phenol concentrations of 36,000 microgm/liter have been detected 40 ft below land surface in a test hole 100 ft south of an overflow impoundment but less than 10 microgm/liter 90 ft below land surface. Samples collected in test holes 1,350 ft downgradient from the surface impoundments and 100 ft north of Pensacola Bay, above and immediately below a clay lens, indicate that phenol contaminated groundwater may not be discharging directly into Pensacola Bay. Phenol concentrations exceeding 20 microgm/liter were detected in samples from a drainage ditch discharging directly into Bayou Chico. Microbiological data collected near the test site suggest that an anaerobic methanogenic ecosystem contributes to a reduction in phenol concentrations in groundwater. A laboratory study using bacteria isolated from the study site indicates that phenol, 2-methylphenol, and 3-methylphenol are significantly degraded and that methanogenesis reduces total phenol concentrations in laboratory digestors by 45%. Pentachlorophenol may inhibit methanogenesis at concentrations exceeding 0.45 milligm/liter. (USGS)

A Phenolic Extract Obtained from Methyl Jasmonate-Treated Strawberries Enhances Apoptosis in a Human Cervical Cancer Cell Line.

PubMed

Spagnuolo, Carmela; Flores, Gema; Russo, Gian Luigi; Ruiz Del Castillo, Maria Luisa

2016-10-01

In the present study, we evaluated the effect of methyl jasmonate (MeJA) treatment on strawberry phenolic composition. Strawberry extracts contain a mixture of phenolic compounds possessing several biological properties. We demonstrated that these extracts were more effective in inducing apoptosis in HeLa cells compared to phenolic preparations derived from untreated strawberries. Treatment of strawberries with 0.5% MeJA resulted in increased polyphenols content (from 7.4 to 8.6 mM quercetin equivalents) and antioxidant properties (from 3.9 to 4.6 mM quercetin equivalents). The identification and quantification of phenolic compounds by liquid chromatography-mass spectrometry in the strawberry extracts showed that cyanidin glucoside, pelargonidin glucoside, and ellagic glucoside acid were significantly higher in strawberries treated with MeJA. Phenolic extracts from MeJA-treated strawberries significantly decreased the cell viability in HeLa cells, compared to extracts derived from untreated fruits. We hypothesized that the enhanced apoptotic activity of MeJA-treated strawberries was due to a synergistic or additive effect of different phenolic compounds present in the extract, rather than the activity of a single molecule.

Extraction, evolution, and sensory impact of phenolic compounds during red wine maceration.

PubMed

Casassa, L Federico; Harbertson, James F

2014-01-01

We review the extraction into wine and evolution of major phenolic classes of sensory relevance. We present a historical background to highlight that previously established aspects of phenolic extraction and retention into red wine are still subjects of much research. We argue that management of the maceration length is one of the most determining factors in defining the proportion and chemical fate of phenolic compounds in wine. The extraction of anthocyanins, flavonols, flavan-3-ols, and oligomeric and polymeric proanthocyanidins (PAs) is discussed in the context of their individual extraction patterns but also with regard to their interaction with other wine components. The same approach is followed to present the sensory implications of phenolic and phenolic-derived compounds in wine. Overall, we conclude that the chemical diversity of phenolic compounds in grapes is further enhanced as soon as vacuolar and pulp components are released upon crushing, adding a variety of new sensory dimensions to the already present chemical diversity. Polymeric pigments formed by the covalent reaction of anthocyanin and PAs are good candidates to explain some of the observed sensory changes in the color, taste, and mouthfeel attributes of red wines during maceration and aging.

Characterization and quantification of phenolic compounds in four tomato (Lycopersicon esculentum L.) farmers' varieties in northeastern Portugal homegardens.

PubMed

Barros, Lillian; Dueñas, Montserrat; Pinela, José; Carvalho, Ana Maria; Buelga, Celestino Santos; Ferreira, Isabel C F R

2012-09-01

Tomato (Lycopersicon esculentum L.) is one of the most widely consumed fresh and processed vegetables in the world, and contains bioactive key components. Phenolic compounds are one of those components and, according to the present study, farmers' varieties of tomato cultivated in homegardens from the northeastern Portuguese region are a source of phenolic compounds, mainly phenolic acid derivatives. Using HPLC-DAD-ESI/MS, it was concluded that a cis p-coumaric acid derivative was the most abundant compound in yellow (Amarelo) and round (Batateiro) tomato varieties, while 4-O-caffeolyquinic acid was the most abundant in long (Comprido) and heart (Coração) varieties. The most abundant flavonoid was quercetin pentosylrutinoside in the four tomato varieties. Yellow tomato presented the highest levels of phenolic compounds (54.23 μg/g fw), including phenolic acids (43.30 μg/g fw) and flavonoids (10.93 μg/g fw). The phenolic compounds profile obtained for the studied varieties is different from other tomato varieties available in different countries, which is certainly related to genetic features, cultivation conditions, and handling and storage methods associated to each sample.

Modeling of experimental treatment of acetaldehyde-laden air and phenol-containing water using corona discharge technique.

PubMed

Faungnawakij, Kajornsak; Sano, Noriaki; Charinpanitkul, Tawatchai; Tanthapanichakoon, Wiwut

2006-03-01

Acetaldehyde-laden air and phenol-contaminated water were experimentally treated using corona discharge reactions and gas absorption in a single water-film column. Mathematical modeling of the combined treatment was developed in this work. Efficient removal of the gaseous acetaldehyde was achieved while the corona discharge reactions produced short-lived species such as O and O- as well as ozone. Direct contact of the radicals and ions with water was known to produce aqueous OH radical, which contributes to the decomposition of organic contaminants: phenol, absorbed acetaldehyde, and intermediate byproducts in the water. The influence of initial phenol concentration ranging from 15 to 50 mg L(-1) and that of influent acetaldehyde ranging from 0 to 200 ppm were experimentally investigated and used to build the math model. The maximum energetic efficiency of TOC, phenol, and acetaldehyde were obtained at 25.6 x 10(-9) mol carbon J(-1), 25.0 x 10(-9) mol phenol J(-1), and 2.0 x 10(-9) mol acetaldehyde J(-1), respectively. The predictions for the decomposition of acetaldehyde, phenol, and their intermediates were found to be in good agreement with the experimental results.

Plant phenolics are detoxified by prophenoloxidase in the insect gut

PubMed Central

Wu, Kai; Zhang, Jie; Zhang, Qiaoli; Zhu, Shoulin; Shao, Qimiao; Clark, Kevin D.; Liu, Yining; Ling, Erjun

2015-01-01

Plant phenolics are a group of important secondary metabolites that are toxic to many animals and insects if ingested at high concentrations. Because most insects consume plant phenolics daily, they have likely evolved the capacity to detoxify these compounds. Here, we used Drosophila melanogaster, Bombyx mori and Helicoverpa armigera as models to study the metabolism of plant phenolics by prophenoloxidases. We found that insect foreguts release prophenoloxidases into the lumen, and that the survival of prophenoloxidase-deletion mutants was impaired when fed several plant phenolics and tea extracts. Using l-DOPA as a model substrate, biochemical assays in large Lepidopteran insects demonstrated that low levels of l-DOPA are rapidly metabolized into intermediates by phenoloxidases. Feeding with excess l-DOPA showed that the metabolic intermediate 5,6-dihydroxyindole reached the hindgut either by passing directly through the midgut, or by transport through the hemolymph. In the hindgut, 5,6-dihydroxyindole was further oxidized by prophenoloxidases. Intermediates exerted no toxicity in the hemocoel or midgut. These results show that plant phenolics are not toxic to insects unless prophenoloxidase genes are lost or the levels of phenolics exceed the catalytic activity of the gut prophenoloxidases. PMID:26592948

"Carbon gain vs. water saving, growth vs. defence": two dilemmas with soluble phenolics as a joker.

PubMed

Karabourniotis, George; Liakopoulos, Georgios; Nikolopoulos, Dimosthenis; Bresta, Panagiota; Stavroulaki, Vassiliki; Sumbele, Sally

2014-10-01

Despite that phenolics are considered as a major weapon against herbivores and pathogens, the primal reason for their evolution may have been the imperative necessity for their UV-absorbing and antioxidant properties in order for plants to compensate for the adverse terrestrial conditions. In dry climates the choice concerning the first dilemma (carbon gain vs. water saving) needs the appropriate structural and metabolic modulations, which protect against stresses such as high UV and visible radiation or drought, but reduce photosynthesis and increase oxidative pressure. Thus, when water saving is chosen, priority is given to protection (including phenolic synthesis), instead of carbon gain and hence growth. At the global level, the different choices by the individual species are expressed by an interspecific negative relationship between total phenolics and photosynthesis. On the other hand, the accumulation of phenolics in water saving plants offers additional defensive functions because these multifunctional compounds can also act as pro-oxidant, antifeeding or toxic factors. Therefore phenolics, as biochemical jokers, can give the answer to both dilemmas: water saving involves high concentrations of phenolics which also offer high level of defence. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Exogenously applied abscisic acid to Yan73 (V. vinifera) grapes enhances phenolic content and antioxidant capacity of its wine.

PubMed

Xi, Zhu-Mei; Meng, Jiang-Fei; Huo, Shan-Shan; Luan, Li-Ying; Ma, Li-Na; Zhang, Zhen-Wen

2013-06-01

Yan73 is a 'teinturier' red wine variety cultivated in China and widely used in winemaking to strengthen red wine colour. The objective of this study was to evaluate the effect of exogenous abscisic acid (ABA) applied to the grapevine cluster on the antioxidant capacity and phenolic content of the wine made from Yan73. Two hundred mg/l ABA was applied on Yan73 grapevine cluster during veraison. As they mature, these ABA-treated and untreated grape berries were transformed into wines, respectively, and the phenolic content and antioxidant capacity of these wines were compared. The results showed that phenolic content (total phenolics, tannins, flavonoids and anthocyanins) and antioxidant capacity were higher in the wine produced with ABA-treated Yan73 grapes than those in the wine from untreated grapes. Compared to Cabernet Sauvignon wine, Yan73 wine had higher phenolic content and stronger antioxidant capacity. These strongly suggest that exogenously applied ABA to Yan73 grapes can enhance phenolic content and antioxidant capacity of its wine, and Yan73 wine has the higher utilization value and potential for development.

Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation.

PubMed

García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

2016-01-01

In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11-16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18-22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9-13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly.

Variability of Virgin Olive Oil Phenolic Compounds in a Segregating Progeny from a Single Cross in Olea europaea L. and Sensory and Nutritional Quality Implications

PubMed Central

Pérez, Ana G.; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

2014-01-01

Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil. PMID:24651694

LC-MS phenolic profiling combined with multivariate analysis as an approach for the characterization of extra virgin olive oils of four rare Tunisian cultivars during ripening.

PubMed

Ben Brahim, Samia; Kelebek, Hasim; Ammar, Sonda; Abichou, Mounir; Bouaziz, Mohamed

2017-08-15

In this work, the phenolic composition of four rare cultivars grown under the same agronomical and environmental conditions was studied. This is to test the effects of cultivars and ripening index essentially on phenolic composition in olive oils as well as tocopherols composition, organoleptic profiling and oxidative properties. Furthermore, some agronomical traits were determined in which a general increase in the size of the fruit and oil contents were recorded for all cultivars. The phenolic fractions were identified and quantified using liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) in multiple reaction monitoring mode (MRM). A total of 13 phenolic compounds belonging to different chemical families were determined. Qualitative and quantitative differences in phenolic composition were observed among cultivars and also among sampling times. On the contrary to the agronomical traits, a general decrease (p<0.05) of total phenolic compounds was observed during maturation. Likewise, a decrease in tocopherols concentrations and oxidative properties was observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effects of heat treatment on the phenolic composition and antioxidant capacity of red wine pomace seasonings.

PubMed

Del Pino-García, Raquel; González-SanJosé, María L; Rivero-Pérez, María D; García-Lomillo, Javier; Muñiz, Pilar

2017-04-15

The impact of thermal processing on the phenolic profile and antioxidant capacity (TAC) of powdered red wine pomace seasonings (RWPSs) obtained from different sources (seedless: Sk-S; whole: W-S; seeds: Sd-S) was assessed. High contents in anthocyanins, flavonol-3-O-glycosides, phenolic acids and flavan-3-ols were found in Sk-S, whereas flavan-3-ols and phenolic acids were the main compounds identified in Sd-S. Reductions in the anthocyanidin and flavonol-3-ol contents mainly determined the effect of heat on the total phenolic contents (Sk-S: -29.4%; W-S: -28.0%; Sd-S: -5.78%), although heating affected positively the phenolic acid and flavonol aglycon contents. Slight TAC decreases were observed in the RWPS-derived extracts (classical Folin-Ciocalteu and ABTS assays). However, higher TAC reductions were detected when the powdered RWPSs were used directly as samples (QUENCHER approach). In conclusion, there is little evidence against submitting RWPSs to thermal processing, as heating affects differently each type of phenolic compound and does not induce very severe TAC decreases in these seasonings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Degradation of phenol using a combination of granular activated carbon adsorption and bipolar pulse dielectric barrier discharge plasma regeneration

NASA Astrophysics Data System (ADS)

Shoufeng, TANG; Na, LI; Jinbang, QI; Deling, YUAN; Jie, LI

2018-05-01

A combined method of granular activated carbon (GAC) adsorption and bipolar pulse dielectric barrier discharge (DBD) plasma regeneration was employed to degrade phenol in water. After being saturated with phenol, the GAC was filled into the DBD reactor driven by bipolar pulse power for regeneration under various operating parameters. The results showed that different peak voltages, air flow rates, and GAC content can affect phenol decomposition and its major degradation intermediates, such as catechol, hydroquinone, and benzoquinone. The higher voltage and air support were conducive to the removal of phenol, and the proper water moisture of the GAC was 20%. The amount of H2O2 on the GAC was quantitatively determined, and its laws of production were similar to phenol elimination. Under the optimized conditions, the elimination of phenol on the GAC was confirmed by Fourier transform infrared spectroscopy, and the total removal of organic carbons achieved 50.4%. Also, a possible degradation mechanism was proposed based on the HPLC analysis. Meanwhile, the regeneration efficiency of the GAC was improved with the discharge treatment time, which attained 88.5% after 100 min of DBD processing.

Berry Phenolics of Grapevine under Challenging Environments

PubMed Central

Teixeira, António; Eiras-Dias, José; Castellarin, Simone D.; Gerós, Hernâni

2013-01-01

Plant phenolics have been for many years a theme of major scientific and applied interest. Grape berry phenolics contribute to organoleptic properties, color and protection against environmental challenges. Climate change has already caused significant warming in most grape-growing areas of the world, and the climatic conditions determine, to a large degree, the grape varieties that can be cultivated as well as wine quality. In particular, heat, drought and light/UV intensity severely affect phenolic metabolism and, thus, grape composition and development. In the variety Chardonnay, water stress increases the content of flavonols and decreases the expression of genes involved in biosynthesis of stilbene precursors. Also, polyphenolic profile is greatly dependent on genotype and environmental interactions. This review deals with the diversity and biosynthesis of phenolic compounds in the grape berry, from a general overview to a more detailed level, where the influence of environmental challenges on key phenolic metabolism pathways is approached. The full understanding of how and when specific phenolic compounds accumulate in the berry, and how the varietal grape berry metabolism responds to the environment is of utmost importance to adjust agricultural practices and thus, modify wine profile. PMID:24030720

Phenolic characterisation of red wines from different grape varieties cultivated in Mendoza province (Argentina).

PubMed

Fanzone, Martín; Zamora, Fernando; Jofré, Viviana; Assof, Mariela; Gómez-Cordovés, Carmen; Peña-Neira, Álvaro

2012-02-01

Knowledge of the chemical composition of wine and its association with the grape variety/cultivar is of paramount importance in oenology and a necessary tool for marketing. Phenolic compounds are very important quality parameters of wines because of their impact on colour, taste and health properties. The aim of the present work was to study and describe the non-flavonoid and flavonoid composition of wines from the principal red grape varieties cultivated in Mendoza (Argentina). Sixty phenolic compounds, including phenolic acids/derivatives, stilbenes, anthocyanins, flavanols, flavonols and dihydroflavonols, were identified and quantified using high-performance liquid chromatography with diode array detection coupled with electrospray ionisation mass spectrometry (HPLC-DAD/ESI-MS). Marked quantitative differences could be seen in the phenolic profile among varieties, especially in stilbenes, acylated anthocyanins and other flavonoids. The polyphenolic content of Malbec wines was higher compared with the other red varieties. Dihydroflavonols represent a significant finding from the chemotaxonomic point of view, especially for Malbec variety. This is the first report on the individual phenolic composition of red wines from Mendoza (Argentina) and suggests that anthocyanins, flavanols and phenolic acids exert a great influence on cultivar-based differentiation. Copyright © 2011 Society of Chemical Industry.

Selective hydrogenation of phenol to cyclohexanone over Pd@CN (N-doped porous carbon): Role of catalyst reduction method

NASA Astrophysics Data System (ADS)

Hu, Shuo; Yang, Guangxin; Jiang, Hong; Liu, Yefei; Chen, Rizhi

2018-03-01

Selective phenol hydrogenation is a green and sustainable technology to produce cyclohexanone. The work focused on investigating the role of catalyst reduction method in the liquid-phase phenol hydrogenation to cyclohexanone over Pd@CN (N-doped porous carbon). A series of reduction methods including flowing hydrogen reduction, in-situ reaction reduction and liquid-phase reduction were designed and performed. The results highlighted that the reduction method significantly affected the catalytic performance of Pd@CN in the liquid-phase hydrogenation of phenol to cyclohexanone, and the liquid-phase reduction with the addition of appropriate amount of phenol was highly efficient to improve the catalytic activity of Pd@CN. The influence mechanism was explored by a series of characterizations. The results of TEM, XPS and CO chemisorption confirmed that the reduction method mainly affected the size, surface composition and dispersion of Pd in the CN material. The addition of phenol during the liquid-phase reduction could inhibit the aggregation of Pd NPs and promote the reduction of Pd (2+), and then improved the catalytic activity of Pd@CN. The work would aid the development of high-performance Pd@CN catalysts for selective phenol hydrogenation.

Variability of virgin olive oil phenolic compounds in a segregating progeny from a single cross in Olea europaea L. and sensory and nutritional quality implications.

PubMed

Pérez, Ana G; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

2014-01-01

Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil.

49 CFR 178.356 - Specification 20PF phenolic-foam insulated, metal overpack.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Specification 20PF phenolic-foam insulated, metal overpack. 178.356 Section 178.356 Transportation Other Regulations Relating to Transportation (Continued... Specification 20PF phenolic-foam insulated, metal overpack. ...

49 CFR 178.356 - Specification 20PF phenolic-foam insulated, metal overpack.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Specification 20PF phenolic-foam insulated, metal overpack. 178.356 Section 178.356 Transportation Other Regulations Relating to Transportation PIPELINE AND... Specification 20PF phenolic-foam insulated, metal overpack. ...

Phenol esterase activity of porcine skin

USDA-ARS?s Scientific Manuscript database

The alkyl esters of plant-derived phenols may serve as slow-release sources for cutaneous delivery of antioxidants. The ability of skin esterases to hydrolyze phenolic esters was examined. Esters of tyrosol and hydroxytyrosol were prepared from decanoic and lipoic acids. Ferulic acid was esterified ...

Spectroscopic analysis of phenolic compounds for food and feed formulations

USDA-ARS?s Scientific Manuscript database

Phenolic compounds exhibit several bioactive properties including anti-oxidant, anti-microbial, and anti-fungal characteristics with potential applications as additives in functional food and feed formulations. Phenolic compounds occur in plants as secondary metabolites and may be recovered as a co-...

Olive oil phenolics are dose-dependently absorbed in humans.

PubMed

Visioli, F; Galli, C; Bornet, F; Mattei, A; Patelli, R; Galli, G; Caruso, D

2000-02-25

Olive oil phenolic constituents have been shown, in vitro, to be endowed with potent biological activities including, but not limited to, an antioxidant action. To date, there is no information on the absorption and disposition of such compounds in humans. We report that olive oil phenolics, namely tyrosol and hydroxytyrosol, are dose-dependently absorbed in humans after ingestion and that they are excreted in the urine as glucuronide conjugates. Furthermore, an increase in the dose of phenolics administered increased the proportion of conjugation with glucuronide.

Carbon-Phenolic Cages for High-Speed Bearings. Part II - Bearing Evaluation with a Multiply-Alkylated Cyclopentane (MAC) Lubricant

DTIC Science & Technology

2003-01-01

program manager for the overall effort. The carbon -phenolic cages were fabricated under the direction of Mr. Wei Shih of Allcomp Inc ., City of...friction. The early carbon -phenolic cages were hand wrapped by Allcomp . Since that time, Allcomp has added a wrapping machine that uses uniform tension...AFRL-PR-WP-TR-2003-2032 CARBON -PHENOLIC CAGES FOR HIGH-SPEED BEARINGS Part II - Bearing Evaluation with a Multiply- Alkylated Cyclopentane (MAC

The thermochemical characteristics of solution of phenol and benzoic acid in water-dimethylsulfoxide and water-acetonitrile mixtures

NASA Astrophysics Data System (ADS)

Zakharov, A. G.; Voronova, M. I.; Batov, D. V.; Smirnova, K. V.

2011-03-01

The solution of phenol and benzoic acid in water-dimethylsulfoxide (DMSO) and water-acetonitrile (AN) mixtures was studied. As distinct from benzoic acid, the thermodynamic characteristics of solution of phenol sharply change at concentrations corresponding to a change in the character of cluster formation in water-DMSO and water-AN mixtures. Differences in the solvation of phenol and benzoic acid are explained by different mechanisms of the interaction of the solutes with clusters existing in binary mixtures.

Phenol-selective mass spectrometric analysis of jet fuel.

PubMed

Zhu, Haoxuan; Janusson, Eric; Luo, Jingwei; Piers, James; Islam, Farhana; McGarvey, G Bryce; Oliver, Allen G; Granot, Ori; McIndoe, J Scott

2017-08-21

Bromobenzyl compounds react selectively with phenols via the Williamson ether synthesis. An imidazolium charge-tagged bromobenzyl compound can be used to reveal phenol impurities in jet fuel by analysis via electrospray ionization mass spectrometry. The complex matrix as revealed by Cold EI GC/MS analysis is reduced to a few simple sets of compounds in the charge-tagged ESI mass spectrum, primarily substituted phenols and thiols. Examination of jet fuels treated by different refinery methods reveals the efficacy of these approaches in removing these contaminants.

Protodeboronation of ortho- and para-phenol boronic acids and application to ortho and meta functionalization of phenols using boronic acids as blocking and directing groups.

PubMed

Lee, Chun-Young; Ahn, Su-Jin; Cheon, Cheol-Hong

2013-12-06

The first metal-free thermal protodeboronation of ortho- and para-phenol boronic acids in DMSO was developed. The protodeboronation was successfully applied to the synthesis of ortho- and meta-functionalized phenols using the boronic acid moiety as a blocking group and a directing group, respectively. Mechanistic studies suggested that this protodeboronation proceeds through the coordination of water to the boron atom followed by σ-bond metathesis.

Porous Media and Mixture Models for Hygrothermal Behavior of Phenolic Composites

NASA Technical Reports Server (NTRS)

Sullivan, Roy M.; Stokes, Eric H.

1999-01-01

Theoretical models are proposed to describe the interaction of water with phenolic polymer. The theoretical models involve the study of the flow of a viscous fluid through a porous media and the thermodynamic theory of mixtures. From the theory, a set of mathematical relations are developed to simulate the effect of water on the thermostructural response of phenolic composites. The expressions are applied to simulate the measured effect of water in a series of experiments conducted on carbon phenolic composites.

Simultaneous determination of phenolic compounds in Cynthiana grape (Vitis aestivalis) by high performance liquid chromatography-electrospray ionisation-mass spectrometry.

PubMed

Ramirez-Lopez, L M; McGlynn, W; Goad, C L; Mireles Dewitt, C A

2014-04-15

Phenolic acids, flavanols, flavonols and stilbenes (PAFFS) were isolated from whole grapes, juice, or pomace and purified using enzymatic hydrolysis. Only anthocyanin mono-glucosides and a few of the oligomers from Cynthiana grape (Vitis aestivalis) were analysed. Flavonoid-anthocyanin mono-glucosides (FA) were isolated using methanol/0.1% hydrochloric acid extraction. In addition, crude extractions of phenolic compounds from Cynthiana grape using 50% methanol, 70% methanol, 50% acetone, 0.01% pectinase, or petroleum ether were also evaluated. Reverse phase high performance liquid chromatography (RP-HPLC) with photodiode array (PDA) detector was used to identify phenolic compounds. A method was developed for simultaneous separation, identification and quantification of both PAFFS and FA. Quantification was performed by the internal standard method using a five points regression graph of the UV-visible absorption data collected at the wavelength of maximum absorbance for each analyte. From whole grape samples nine phenolic compounds were tentatively identified and quantified. The individual phenolic compounds content varied from 3 to 875 mg kg⁻¹ dry weight. For juice, twelve phenolic compounds were identified and quantified. The content varied from 0.07 to 910 mg kg⁻¹ dry weight. For pomace, a total of fifteen phenolic compounds were tentatively identified and quantified. The content varied from 2 mg kg⁻¹ to 198 mg kg⁻¹ dry matter. Results from HPLC analysis of the samples showed that gallic acid and (+)-catechin hydrate were the major phenolic compounds in both whole grapes and pomace. Cyanidin and petunidin 3-O-glucoside were the major anthocyanin glucosides in the juice. Published by Elsevier Ltd.

Effects of fungal degradation on the CuO oxidation products of lignin: A controlled laboratory study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hedges, J.I.; Weliky, K.; Devol, A.H.

1988-11-01

Duplicate samples of birch wood were degraded for 0, 4, 8 and 12 weeks by the white-rot fungus, Phlebia tremellosus, and for 12 weeks by 6 other white-rot and brown-rot fungi. P. tremellosus caused progressive weight losses and increased the H/C and O/C of the remnant wood by preferentially degrading the lignin component of the middle lamellae. Total yields of syringyl phenols were decreased 1.5 times as fast as total vanillyl phenol yields. Within both phenol families, aldehyde precursors were degraded faster than precursors of the corresponding ketones, which were obtained in constant proportion to the total phenol yield. Althoughmore » two other white-rot fungi caused similar lignin compositional trends, a fourth white-rot species, Coriolus versicolor, simultaneously eroded all cell wall components and did not concentrate polysaccharides in the remnant wood. The brown-rot fungi also preferentially attacked syringyl structural units, but degraded all phenol precursors at a much slower rate than the white-rotters and did not produce excess vanillic acid. Degradation by P. tremellosus linearly increased the vanillic acid/vanillin ratio, (Ad/Al)v, of the remnant birch wood throughout the 12 week degradation study and exponentially decreased the absolute yields of total vanillyl phenols, total syringyl phenols and the syringyl/vanillyl phenol ratio, S/V. At the highest (Ad/Al)v of 0.50 total yields of syringyl and vanillyl phenols were decreased by 65% and 80%, respectively, with a resulting reduction of 40% in the original S/V. Many of the diagenetically related compositional trends that have been previously reported for lignins in natural environments can be explained by white-rot fungal degradation.« less

Control of occupational exposure to phenol in industrial wastewater treatment plant of a petroleum refinery in Alexandria, Egypt: An intervention application case study.

PubMed

Zaki, Gehan R; El-Marakby, Fadia A; Ramadan, Alaa El-Din K; Issa, Ahmed I; Nofal, Faten H

2016-11-01

Phenol exposure is one of the hazards in the industrial wastewater treatment basin of any refinery. It additively interacts with hydrogen sulfide emitted from the wastewater basin. Consequently, its concentration should be greatly lower than its threshold limit value. The present study aimed at controlling occupational exposure to phenol in the work environment of wastewater treatment plant in a refinery by reducing phenolic compounds in the industrial wastewater basin. This study was conducted on both laboratory and refinery scales. The first was completed by dividing each wastewater sample from the outlets of different refinery units into three portions; the first was analyzed for phenolic compounds. The second and third were for laboratory scale charcoal and bacterial treatments. The two methods were compared regarding their simplicities, design, and removal efficiencies. Accordingly, bacterial treatment by continuous flow of sewage water containing Pseudomonas Aeruginosa was used for refinery scale treatment. Laboratory scale treatment of phenolic compounds revealed higher removal efficiency of charcoal [100.0(0.0) %] than of bacteria [99.9(0.013) %]. The refinery scale bacterial treatment was [99.8(0.013) %] efficient. Consequently, level of phenol in the work environment after refinery-scale treatment [0.069(0.802) mg/m(3)] was much lower than that before [5.700(26.050) mg/m(3)], with removal efficiency of [99.125(2.335) %]. From the present study, we can conclude that bacterial treatment of phenolic compounds in industrial wastewater of the wastewater treatment plant using continuous flow of sewage water containing Pseudomonas Aeruginosa reduces the workers' exposure to phenol.

Phenolic profile and antioxidant activity of extracts prepared from fermented heat-stabilized defatted rice bran.

PubMed

Webber, Daniel M; Hettiarachchy, Navam S; Li, Ruiqi; Horax, Ronny; Theivendran, Sivarooban

2014-11-01

Heat-stabilized, defatted rice bran (HDRB) serves as a potential source of phenolic compounds which have numerous purported health benefits. An estimated 70% of phenolics present in rice bran are esterified to the arabinoxylan residues of the cell walls. Release of such compounds could provide a value-added application for HDRB. The objective of this study was to extract and quantify phenolics from HDRB using fermentation technology. Out of 8 organisms selected for rice bran fermentation, Bacillus subtilis subspecies subtilis had the maximum phenolic release of 26.8 mg ferulic acid equivalents (FAE) per gram HDRB. Response surface methodology was used to further optimize the release of rice bran phenolics. An optimum of 28.6 mg FAE/g rice bran was predicted at 168 h, 0.01% inoculation level, and 100 mg HDRB/mL. Fermentation of HDRB for 96 h with B. subtilis subspecies subtilis resulted in a significant increase in phenolic yield, phenolic concentration, and radical scavenging capacity. Fermented rice bran had 4.86 mg gentistic acid, 1.38 mg caffeic acid, 6.03 mg syringic acid, 19.02 mg (-)-epicatechin, 4.08 mg p-courmaric acid, 4.64 mg ferulic acid, 10.04 mg sinapic acid, and 17.59 mg benzoic acid per 100 g fermented extract compared to 0.65 mg p-courmaric acid and 0.36 mg ferulic acid per 100 g nonfermented extract. The high phenolic content and antioxidant activity of fermented HDRB extract indicates that rice bran fermentation under optimized condition is a potential means of meeting the demand for an effective and affordable antioxidant. © 2014 Institute of Food Technologists®

Phenolic Extracts from Clerodendrum volubile Leaves Inhibit Cholinergic and Monoaminergic Enzymes Relevant to the Management of Some Neurodegenerative Diseases.

PubMed

Oboh, Ganiyu; Ogunruku, Omodesola O; Oyeleye, Sunday I; Olasehinde, Tosin A; Ademosun, Ayokunle O; Boligon, Aline Augusti

2017-05-04

This study investigated the inhibitory effects of phenolic-rich extracts from Clerodendrum volubile leaves on cholinergic [acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)] and monoaminergic [monoamine oxidase (MAO)] enzymes' activities and pro-oxidants [Fe 2+ and quinolinic acid-(QA)] induced lipid peroxidation in rats brain homogenates in vitro. Free phenolic extracts (FPE) and bound phenolic extracts (BPE) were obtained via solvent extraction, and the total phenol and flavonoid contents were evaluated. The phenolic constituents of the extracts were also determined using high performance liquid chromatography coupled with diode array detector (HPLC-DAD). Our findings revealed that FPE had higher AChE (2.06 μg/mL), BChE (2.79 μg/mL), and MAO (2.81 μg/mL) inhibitory effects than BPE [AChE, 2.80 μg/mL; BChE, 3.40 μg/mL; MAO, 3.39 μg/mL]. Furthermore, FPE also had significantly (P < 0.05) higher inhibitory effects on Fe 2+ and QA-induced lipid peroxidation compared to BPE. FPE (162.61 mg GAE/g) had higher total phenol content than BPE. However, BPE (18.65 mg QE/g) had significantly higher total flavonoid content than FPE (13.32 mg QE/g). Phenolic acids (such as gallic acid, catechin, chlorogenic, caffeic, ellagic, p-Coumaric acids) and flavonoids (catechins, rutin and quercetin) were present in both extracts. This study revealed that the enzymes' inhibitory activities and antioxidant potentials of phenolic-rich extracts from C. volubile could be part of the mechanism of actions behind its use for memory/cognitive function as obtained in folklore. However, FPE exhibited significantly higher enzymes, inhibitory and antioxidant potentials than BPE.

Importance of phenols structure on their activity as antinitrosating agents: A kinetic study

PubMed Central

Pessêgo, Márcia; Rosa da Costa, Ana M; Moreira, José A.

2011-01-01

Objective: Nitrosative deamination of DNA bases induced by reaction with reactive nitrogen species (RNS) has been pointed out as a probable cause of mutagenesis. (Poly)phenols, present in many food items from the Mediterranean diet, are believed to possess antinitrosating properties due to their RNS scavenging ability, which seems to be related to their structure. It has been suggested that phenolic compounds will react with the above-mentioned species more rapidly than most amino compounds, thus preventing direct nitrosation of the DNA bases and their transnitrosation from endogenous N-nitroso compounds, or most likely from the transient N-nitrosocompounds formed in vivo. Materials and Methods: In order to prove that assumption, a kinetic study of the nitroso group transfer from a N-methyl-N-nitrosobenzenesulfonamide (N-methyl-N-nitroso-4-methylbenzenesulfonamide, MeNMBS) to the DNA bases bearing an amine group and to a series of phenols was carried out. In the transnitrosation of phenols, the formation of nitrosophenol was monitored by Ultraviolet (UV) / Visible spectroscopy, and in the reactions of the DNA bases, the consumption of MeNMBS was followed by high performance liquid chromatography (HPLC). Results: The results obtained point to the transnitrosation of DNA bases being negligible, as well as that of phenols bearing electron-withdrawing groups. Phenols with methoxy substituents in positions 2, 4, and / or 6, although they seemed to react, did not afford the expected product. Phenols with electron-releasing substituents, unless these blocked the oxygen atom, reacted with our model compound at an appreciable rate. O-nitrosation of the phenolate ion followed by rearrangement of the C-nitrosophenol seemed to be involved. Conclusion: This study provided evidence that the above compounds might actually act as antinitrosating agents in vivo. PMID:21430963

Phenolic acids as bioindicators of fly ash deposit revegetation.

PubMed

Djurdjević, L; Mitrović, M; Pavlović, P; Gajić, G; Kostić, O

2006-05-01

The floristic composition, the abundance, and the cover of pioneer plant species of spontaneously formed plant communities and the content of total phenolics and phenolic acids, as humus constituents, of an ash deposit after 7 years of recultivation were studied. The restoration of both the soil and the vegetation on the ash deposits of the "Nikola Tesla-A" thermoelectric power plant in Obrenovac (Serbia) is an extremely slow process. Unfavorable physical and chemical characteristics, the toxicity of fly ash, and extreme microclimatic conditions prevented the development of compact plant cover. The abundance and cover of plants increased from the central part of the deposit towards its edges (ranging from 1-80%). Festuca rubra L., Crepis setosa Hall., Erigeron canadensis L., Cirsium arvense (L.) Scop., Calamagrostis epigeios (L.) Roth., and Tamarix gallica L. were the most abundant species, thus giving the highest cover. Humus generated during the decomposition process of plant remains represents a completely new product absent in the ash as the starting material. The amount of total phenolics and phenolic acids (38.07-185.16 microg/g of total phenolics and 4.12-27.28 microg/g of phenolic acids) in fly ash increased from the center of the deposit towards its edges in correlation with the increase in plant abundance and cover. Ash samples contained high amounts of ferulic, vanillic, and p-coumaric acid, while the content of both p-hydroxybenzoic and syringic acid was relatively low. The presence of phenolic acids indicates the ongoing process of humus formation in the ash, in which the most abundant pioneer plants of spontaneously formed plant communities play the main role. Phenolic compounds can serve as reliable bioindicators in an assessment of the success of the recultivation process of thermoelectric power plants' ash deposits.

Phenol and terpene quenching of singlet- and triplet-excited states of riboflavin in relation to light-struck flavor formation in beer.

PubMed

Cardoso, Daniel R; Olsen, Karsten; Møller, Jens K S; Skibsted, Leif H

2006-07-26

Phenolic compounds present in beer were shown by fluorescence spectroscopy and laser flash photolysis to deactivate both singlet- and triplet-excited states of riboflavin with bimolecular rate constants close to the diffusion control ranging from 2.8x10(9) to 1.1x10(10) M-1 s-1 and from 1.1x10(9) to 2.6x10(9) M-1 s-1, respectively. Enthalpies of activation were low (up to 33.2 kJ mol-1), and entropies of activation were positive, ranging from 17 to 92 J mol-1 K-1, as derived from temperature dependence, indicating a compensation effect. From a Stern-Volmer analysis of the singlet-excited riboflavin quenching by phenols it was found that high amounts of phenolic compounds (>0.3 M) would be needed to hinder triplet-excited riboflavin generation. On the other hand, a phenolic content of 0.36 mM is likely to quench 90% of the triplet-excited state. Phenol photodegradation was found to be complex, and using ESI-MS analysis it was not possible to identify specific photooxidation products of the phenolic compounds; only the photoproducts of riboflavin could be detected and structurally assigned. The rate of reaction of triplet-excited riboflavin with phenolic compounds in acetonitrile/citrate buffer (pH 4.6, 10 mM) is 550 times faster than the reaction with iso-alpha-acids from hops, indicating that triplet-excited quenchers such as phenols may be involved in the early steps in light-struck flavor formation in beer through radical formation. Terpenes present in herb-flavored beers were found to be nonreactive toward singlet- and triplet-excited-state riboflavin, and any protection depends on other mechanisms.

Differential Degradation of Nonylphenol Isomers by Sphingomonas xenophaga Bayram

PubMed Central

Gabriel, Frédéric L. P.; Giger, Walter; Guenther, Klaus; Kohler, Hans-Peter E.

2005-01-01

Sphingomonas xenophaga Bayram, isolated from the activated sludge of a municipal wastewater treatment plant, was able to utilize 4-(1-ethyl-1,4-dimethylpentyl)phenol, one of the main isomers of technical nonylphenol mixtures, as a sole carbon and energy source. The isolate degraded 1 mg of 4-(1-ethyl-1,4-dimethylpentyl)phenol/ml in minimal medium within 1 week. Growth experiments with five nonylphenol isomers showed that the three isomers with quaternary benzylic carbon atoms [(1,1,2,4-tetramethylpentyl)phenol, 4-(1-ethyl-1,4-dimethylpentyl)phenol, and 4-(1,1-dimethylheptyl)phenol] served as growth substrates, whereas the isomers containing one or two hydrogen atoms in the benzylic position [4-(1-methyloctyl)phenol and 4-n-nonylphenol] did not. However, when the isomers were incubated as a mixture, all were degraded to a certain degree. Differential degradation was clearly evident, as isomers with more highly branched alkyl side chains were degraded much faster than the others. Furthermore, the C9 alcohols 2,3,5-trimethylhexan-2-ol, 3,6-dimethylheptan-3-ol, and 2-methyloctan-2-ol, derived from the three nonylphenol isomers with quaternary benzylic carbon atoms, were detected in the culture fluid by gas chromatography-mass spectrometry, but no analogous metabolites could be found originating from 4-(1-methyloctyl)phenol and 4-n-nonylphenol. We propose that 4-(1-methyloctyl)phenol and 4-n-nonylphenol were cometabolically transformed in the growth experiments with the mixture but that, unlike the other isomers, they did not participate in the reactions leading to the detachment of the alkyl moiety. This hypothesis was corroborated by the observed accumulation in the culture fluid of an as yet unidentified metabolite derived from 4-(1-methyloctyl)phenol. PMID:15746308

The effect of phenol composition on the sensory profile of smoke affected wines.

PubMed

Kelly, David; Zerihun, Ayalsew

2015-05-26

Vineyards exposed to wildfire generated smoke can produce wines with elevated levels of lignin derived phenols that have acrid, metallic and smoky aromas and flavour attributes. While a large number of phenols are present in smoke affected wines, the effect of smoke vegetation source on the sensory descriptors has not been reported. Here we report on a descriptive sensory analysis of wines made from grapes exposed to different vegetation sources of smoke to examine: (1) the effect vegetation source has on wine sensory attribute ratings and; (2) associations between volatile and glycoconjugated phenol composition and sensory attributes. Sensory attribute ratings were determined by a trained sensory panel and phenol concentrations determined by gas chromatography-mass spectroscopy. Analysis of variance, principal component analysis and partial least squares regressions were used to evaluate the interrelationships between the phenol composition and sensory attributes. The results showed that vegetation source of smoke significantly affected sensory attribute intensity, especially the taste descriptors. Differences in aroma and taste from smoke exposure were not limited to an elevation in a range of detractive descriptors but also a masking of positive fruit descriptors. Sensory differences due to vegetation type were driven by phenol composition and concentration. In particular, the glycoconjugates of 4-hydroxy-3-methoxybenzaldehyde (vanillin), 1-(4-hydroxy-3-methoxyphenyl)ethanone (acetovanillone), 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde) and 1-(4-hydroxy-3,5-dimethoxyphenyl)ethanone (acetosyringone) concentrations were influential in separating the vegetation sources of smoke. It is concluded that the detractive aroma attributes of smoke affected wine, especially of smoke and ash, were associated with volatile phenols while the detractive flavour descriptors were correlated with glycoconjugated phenols.

Analysis of annual fluctuations in the content of phenol, chlorophenols and their derivatives in chlorinated drinking waters.

PubMed

Michałowicz, Jaromir; Stufka-Olczyk, Jadwiga; Milczarek, Anna; Michniewicz, Małgorzata

2011-08-01

Chlorophenols are widely represented, toxic, and persistent environmental pollutants. In this work, we analyzed annual fluctuations in the content of phenol, guaiacol, chlorophenols, chlorocatechols, and chlorinated methoxyphenols in drinking water collected in Warsaw and Tomaszów Mazowiecki (Poland). Moreover, the effect of dissolved organic matter content on the occurrence of phenolic compounds in drinking water was studied. The compounds were adsorbed on octadecyl C18 solid-phase discs, separated by the use of gas chromatography, and analyzed using mass spectrometry. The content of organic matter was evaluated by the analysis of UV absorption at 254 nm by water samples. In Warsaw, raw water (derived from infiltration intakes situated in the Vistula River) and treated water (subjected to coagulation, filtration, and disinfection with chlorine dioxide) were collected in order to analyze phenols. In Tomaszów Mazowiecki, raw water (taken directly form the river) and treated water (subjected to coagulation, sand filtration, ozonation, and disinfection with gaseous chlorine) were taken to determine phenolic substances. The obtained results showed the occurrence of phenol, guaiacol, 2,4,6-trichlorophenol (2,4,6-TCP), tetrachlorophenol (TeCP), and pentachlorophenol in drinking water of both cities. Occasionally, in the waters studied, the appearance of chloroguaiacols, 3-chlorosyringol, and some chlorocatechols were noted. It was also observed that the content of dissolved organic matter in river waters may have contributed to the formation of some phenols, e.g., phenol, guaiacol, 2,4,6-TCP, and TeCP in drinking water. Finally, it was found that there were no annual (seasonal) fluctuations in phenolic compounds contents in drinking waters examined.

The influence of L-phenylalanine, methyl jasmonate and sucrose concentration on the accumulation of phenolic acids in Exacum affine Balf. f. ex Regel shoot culture.

PubMed

Skrzypczak-Pietraszek, Ewa; Słota, Joanna; Pietraszek, Jacek

2014-01-01

Phenolic acids are an important group of plant secondary metabolites with various, valuable therapeutic properties. Apart from plants growing in the open air, tissue cultures can be an alternative source of the secondary metabolites. The yield of their accumulation in in vitro cultures can be increased by different methods, including culture medium supplementation with precursors, elicitors and changing the standard amounts of the medium components. The purpose of this study was to investigate the influence of the precursor (L-phenylalanine), the elicitor (methyl jasmonate) and a higher sucrose concentration on the phenolic acids accumulation in the agitated shoot cultures of Exacum affine Balf. f. ex Regel (Gentianaceae). Qualitative and quantitative analyses of the phenolic acids in methanolic extracts from the biomass were conducted by applying the HPLC method. Fourteen phenolic acids and cinnamic acid were found in all samples. The total content of free phenolic acids increased from approximately 0.242% to 0.635% (2.6-fold) and the total content of the whole phenolic acids (free and bound) - from 0.712% to 1.160% (1.6-fold). The studies show that the best variant for the accumulation of most of the identified phenolic acids contained 6% of sucrose (double the standard amount), L-phenylalanine 1.6 gL(-1) of medium and methyl jasmonate 100 μM. The analysis of the results in the experiment presented here showed that it is possible to increase the accumulation of the phenolic acids in Exacum affine shoot cultures - by adding the precursor (L-phenylalanine), the elicitor (methyl jasmonate) and by increasing the sucrose concentration.

Improving phenolic bioactive-linked anti-hyperglycemic functions of dark germinated barley sprouts (Hordeum vulgare L.) using seed elicitation strategy.

PubMed

Ramakrishna, Ramnarain; Sarkar, Dipayan; Manduri, Avani; Iyer, Shreyas Ganesan; Shetty, Kalidas

2017-10-01

Sprouts of cereal grains, such as barley ( Hordeum vulgare L.), are a good source of beneficial phenolic bioactives. Such health relevant phenolic bioactives of cereal sprouts can be targeted to manage chronic hyperglycemia and oxidative stress commonly associated with type 2 diabetes (T2D). Therefore improving phenolic bioactives by stimulating plant endogenous defense responses such as protective pentose phosphate pathway (PPP) during sprouting has significant merit. Based on this metabolic rationale, this study aimed to enhance phenolic bioactives and associated antioxidant and anti-hyperglycemic functions in dark germinated barley sprouts using exogenous elicitor treatments. Dark-germinated sprouts of two malting barley cultivars (Pinnacle and Celebration), treated with chitosan oligosaccharide (COS) and marine protein hydrolysate (GP), were evaluated. Total soluble phenolic content (TSP), phenolic acid profiles, total antioxidant activity (TA) and in vitro inhibitory activities of hyperglycemia relevant α-amylase and α-glucosidase enzymes of the dark germinated barley sprouts were evaluated at day 2, 4, and 6 post elicitor treatments. Overall, TSP content, TA, and α-amylase inhibitory activity of dark germinated barley sprouts decreased, while α-glucosidase inhibitory activity and gallic acid content increased from day 2 to day 6. Among barley cultivars, high phenolic antioxidant-linked anti-hyperglycemic bioactives were observed in Celebration. Furthermore, GP and COS seed elicitor treatments in selective doses improved T2D relevant phenolic-linked anti-hyperglycemic bioactives of barley spouts at day 6. Therefore, such seed elicitation approach can be strategically used to develop bioactive enriched functional food ingredients from cereal sprouts targeting chronic hyperglycemia and oxidative stress linked to T2D.

Effect of post cure time and temperature on the properties of two phenolic-fiber composites

NASA Technical Reports Server (NTRS)

Lucy, M. H.; Price, H. L.

1975-01-01

Some effects of post-cure time and temperature on the physicomechanical properties of a phenolic-asbestos and a phenolic-glass composite are studied. The molding and post-curing procedures are discussed along with physical and mechanical test results. It is found that the specific gravity of the panels tested decreased slightly but the hardness always increased with post cure, and that the mechanical properties had different patterns of response to increasing post-cure time and temperature. For tensile properties, strength decreased, modulus increased, and elongation at break exhibited little change. In general, the phenolic-asbestos showed more positive response to post cure than did the phenolic-glass. Mold venting is found to impart better properties to the composites concerned.

Statistical optimization of process parameters for the simultaneous adsorption of Cr(VI) and phenol onto Fe-treated tea waste biomass

NASA Astrophysics Data System (ADS)

Gupta, Ankur; Balomajumder, Chandrajit

2017-12-01

In this study, simultaneous removal of Cr(VI) and phenol from binary solution was carried out using Fe-treated tea waste biomass. The effect of process parameters such as adsorbent dose, pH, initial concentration of Cr(VI) (mg/L), and initial concentration of phenol (mg/L) was optimized. The analysis of variance of the quadratic model demonstrates that the experimental results are in good agreement with the predicted values. Based on experimental design at an initial concentration of 55 mg/L of Cr(VI), 27.50 mg/L of phenol, pH 2.0, 15 g/L adsorbent dose, 99.99% removal of Cr(VI), and phenol was achieved.

Electrocatalytic Hydrogenation of Phenol over Platinum and Rhodium: Unexpected Temperature Effects Resolved

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Nirala; Song, Yang; Gutiérrez, Oliver Y.

2016-11-04

Both electrocatalytic hydrogenation (ECH) and thermal hydrogenation (TH) of phenol by Pt and Rh show a roll-over in rate with increasing temperature without changing the principal reaction pathways. The negative effect of temperature for aqueous-phase phenol H2 and electrocatalytic hydrogenation on Pt and Rh is deduced to be due to the unexpected buildup of dehydrogenated phenol adsorbates, which block active sites. Rates of ECH and TH increase similarly with increasing hydrogen chemical potential whether induced by applied potential or H2 pressure, both via increasing H coverage, and indirectly by removing site blockers, a very strong effect at high temperature. Thismore » enables unprecedented rates in the TH of phenol at these temperatures.« less

Ultrasonically assisted extraction of total phenols and flavonoids from Rhodiola rosea.

PubMed

Staneva, Jordanka; Todorova, Milka; Neykov, Neyko; Evstatieva, Ljuba

2009-07-01

This work deals with ultrasonically assisted extraction (UAE) of biologically active compounds from rhizomes of Rhodiola rosea, a popular medicinal plant. The influence of temperature, type of solvent and solid/solvent ratio on the yield of total extracts, total phenols and flavonoids was established. The best extraction of total phenols and flavonoids was achieved by using 50% aqueous EtOH and MeOH, respectively. Five times increase of solid/solvent ratio (from 1:20 to 1:100 (w/v)) leads to slow increase of the yield of total phenols and flavonoids. The extraction effectiveness of conventional maceration with 50% EtOH and UAE performed for 1 h at 25 degrees C using the same solvent with respect of total phenols was comparable.

Carbon phenolic heat shields for Jupiter/Saturn/Uranus entry probes

NASA Technical Reports Server (NTRS)

Mezines, S.

1974-01-01

Carbon phenolic heat shield technology is reviewed. Heat shield results from the outer planetary probe mission studies are summarized along with results of plasma jet testing of carbon phenolic conducted in a ten megawatt facility. Missile flight data is applied to planetary entry conditions. A carbon phenolic heat shield material is utilized and tailored to accommodate each of the probe missions. An integral heat shield approach is selected over in order to eliminate a high temperature interface problem and permit direct bonding of the carbon phenolic to the structural honeycomb sandwich. The sandwich is filled with a very fine powder to minimize degradation of its insulation properties by the high conductive hydrogen/helium gases during the long atmospheric descent phase.

40 CFR 721.3812 - Substituted phenols and formaldehyde polymer, alkylated (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... polymer, alkylated (generic). 721.3812 Section 721.3812 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.3812 Substituted phenols and formaldehyde polymer... substance identified generically as substituted phenols and formaldehyde polymer, alkylated (PMN P-00-0542...

40 CFR 721.3812 - Substituted phenols and formaldehyde polymer, alkylated (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... polymer, alkylated (generic). 721.3812 Section 721.3812 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.3812 Substituted phenols and formaldehyde polymer... substance identified generically as substituted phenols and formaldehyde polymer, alkylated (PMN P-00-0542...

Antioxidants and phenolic secretion in sugarcane genotypes shoot culture

USDA-ARS?s Scientific Manuscript database

The secretion of phenolic compounds is a major limitation for sugarcane in vitro culture, causing a loss of regenerative capacity and subsequent cell death. In this study, micropropagation and phenolic secretion of four Saccharum genotypes in the presence of different antioxidants were evaluated. As...

SOLVENT-FREE TETRAHYDROPYRANYLATION (THP) OF ALCOHOLS AND PHENOLS AND THEIR REGENERATION BY CATALYTIC ALUMINUM CHLORIDE HEXAHYDRATE

EPA Science Inventory

Catalytic amount of aluminum chloride hexahydrate enables solvent-free tetrahydropyranylation (THP) of alcohols and phenols at moderate temperatures. A simple addition of methanol helps to regenerate the corresponding alcohols and phenols thus rendering these protection and depro...

Phenolic composition, anitproliferative and anti-inflammatory properties of conventional and organic cinnamon and peppermint

USDA-ARS?s Scientific Manuscript database

Conventional and organic cinnamon and peppermint were investigated for their phenolic profile, antiproliferative, anti-inflammatory, and antioxidant properties. Accelerated solvent extraction (ASE) with 75% acetone was a better method than Soxhlet and overnight extraction for phenolic content and a...

40 CFR 721.3812 - Substituted phenols and formaldehyde polymer, alkylated (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... polymer, alkylated (generic). 721.3812 Section 721.3812 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.3812 Substituted phenols and formaldehyde polymer... substance identified generically as substituted phenols and formaldehyde polymer, alkylated (PMN P-00-0542...

40 CFR 721.3812 - Substituted phenols and formaldehyde polymer, alkylated (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... polymer, alkylated (generic). 721.3812 Section 721.3812 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.3812 Substituted phenols and formaldehyde polymer... substance identified generically as substituted phenols and formaldehyde polymer, alkylated (PMN P-00-0542...

40 CFR 721.3812 - Substituted phenols and formaldehyde polymer, alkylated (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... polymer, alkylated (generic). 721.3812 Section 721.3812 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.3812 Substituted phenols and formaldehyde polymer... substance identified generically as substituted phenols and formaldehyde polymer, alkylated (PMN P-00-0542...

Bromination of Phenol

ERIC Educational Resources Information Center

Talbot, Christopher

2013-01-01

This "Science note" examines the bromination of phenol, a reaction that is commonly taught at A-level and IB (International Baccalaureate) as an example of electrophilic substitution. Phenol undergoes bromination with bromine or bromine water at room temperature. A white precipitate of 2,4,6-tribromophenol is rapidly formed. This…

Lipid encapsulated phenolics

USDA-ARS?s Scientific Manuscript database

Phenolic compounds have numerous health benefits when included in the human diet and have emerged as a functional food and feed additive. Current sources of phenolics include commodity grains such as corn, oat, and wheat but may also be obtained as a co-product from agricultural residues and other l...

Phenolic composition and antioxidant capacity of Ugni molinae Turcz. leaves of different genotypes.

PubMed

Peña-Cerda, Marcelo; Arancibia-Radich, Jorge; Valenzuela-Bustamante, Paula; Pérez-Arancibia, Rodrigo; Barriga, Andrés; Seguel, Ivette; García, Lorena; Delporte, Carla

2017-01-15

Ugni molinae Turcz. is a native shrub of Chile, known for its edible berries and its leaves, which have been the focus of recent attention, as a good source of phenolic compounds to be used in cosmetics and food products. The aim of this study was to assess the differences in the phenolic composition and antioxidant capacity of the ethanolic extracts from the leaves of 10 genotypes of U. molinae, that were cultivated under the same soil, climate and agronomical management. Antioxidant activity was assessed by complementary methods (ORAC-Fl, FRAP and DPPH assay), phenolic composition of each extract was analyzed by LC-MS. Phenolic and flavonoid total contents were determined by Folin-Ciocalteu and AlCl3 methods. Significative differences were found by these methods, and ellagitannins, gallic acid derivatives and flavonols were identified as responsible for these differences, showing the influence of the genotype on the phenolic composition of U. molinae leaves. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electricity generation and removal performance of a microbial fuel cell using sulfonated poly (ether ether ketone) as proton exchange membrane to treat phenol/acetone wastewater.

PubMed

Wu, Hao; Fu, Yu; Guo, Chunyu; Li, Yanbo; Jiang, Nanzhe; Yin, Chengri

2018-07-01

The microbial fuel cell (MFC) has emerged as a promising technology for wastewater treatment and energy recovery, but the expensive cost of proton exchange membranes (PEMs) is a problem that need to be solved. In this study, a two-chamber MFC based on our self-made PEM sulfonated poly (ether ether ketone) membrane was set up to treat phenol/acetone wastewater and synchronously generate power. The maximum output voltage was 240-250 mV. Using phenol and acetone as substrates, the power generation time in an operation cycle was 289 h. The MFC exhibited good removal performance, with no phenol or acetone detected, respectively, when the phenol concentration was lower than 50 mg/L and the acetone concentration was lower than 100 mg/L. This study provides a cheap and eco-friendly way to treat phenol/acetone wastewater and generate useful energy by MFC technology. Copyright © 2018 Elsevier Ltd. All rights reserved.

Antioxidant capacities and total phenolic contents increase with gamma irradiation in two types of Malaysian honey.

PubMed

Hussein, Saba Zuhair; Yusoff, Kamaruddin Mohd; Makpol, Suzana; Yusof, Yasmin Anum Mohd

2011-07-27

Two types of monofloral Malaysian honey (Gelam and Nenas) were analyzed to determine their antioxidant activities and total phenolic and flavonoid contents, with and without gamma irradiation. Our results showed that both types of honey can scavenge free radicals and exhibit high antioxidant-reducing power; however, Gelam honey exhibited higher antioxidant activity (p < 0.05) than Nenas honey, which is in good correlation (r = 0.9899) with its phenolic contents. Interestingly, we also noted that both irradiated honeys have higher antioxidant activities and total phenolic and flavonoid contents compared to nonirradiated honeys by Folin-Ciocalteu and UV-spectrophotometry methods, respectively. However, HPLC analysis for phenolic compounds showed insignificant increase between irradiated and nonirradiated honeys. The phenolic compounds such as: caffeic acid, chlorogenic acid, ellagic acid, p- coumaric acid, quercetin and hesperetin as indicated by HPLC method were found to be higher in Gelam honey versus Nenas honey. In conclusion, irradiation of honey causes enhanced antioxidant activities and flavonoid compounds.

Phenolic acids and methylxanthines composition and antioxidant properties of mate (Ilex paraguariensis) residue.

PubMed

Vieira, Manoela A; Maraschin, Marcelo; Pagliosa, Cristiane M; Podestá, Rossana; de Simas, Karina N; Rockenbach, Ismael Ivan; Amboni, Renata D de M C; Amante, Edna R

2010-04-01

Ilex paraguariensis is known to contain compounds with antioxidant properties, such as phenolic acids, and its stimulant properties are attributed to methylxanthines, such as caffeine. The aims of this study were to evaluate the phenolic, methylxanthinic, and tannin composition of a mate residue (mate powder), to compare the quali-quantitative phenolic composition and the antioxidant potential of extracts obtained from distinct solvent systems. Among the extracts prepared with different solvents, the 80% methanol extract showed the highest total polyphenol content (11.51 g/100 g) and antioxidant activity. HPLC analysis showed that 4,5 dicaffeoylquinic acid is the major component of the phenolic fraction of mate powder. The caffeine, theobromine, and tannin contents in mate powder were 1.01, 0.10, and 0.29 g/100 g, respectively. Consumption of mate powder would significantly contribute to antioxidant and stimulant intake, providing high amounts of phenolic acids, tannins, and methylxanthines with biological effects potentially beneficial for human health. This article contributes to the minimization of residues in yerba-mate processing.

The Potential of Plant Phenolics in Prevention and Therapy of Skin Disorders

PubMed Central

Działo, Magdalena; Mierziak, Justyna; Korzun, Urszula; Preisner, Marta; Szopa, Jan; Kulma, Anna

2016-01-01

Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract. PMID:26901191

Influence of Fermentation with Different Lactic Acid Bacteria and in Vitro Digestion on the Biotransformation of Phenolic Compounds in Fermented Pomegranate Juices.

PubMed

Valero-Cases, Estefanía; Nuncio-Jáuregui, Nallely; Frutos, María José

2017-08-09

This study describes the effect of fermentation and the impact of simulated gastrointestinal digestion (SGD) of four fermented pomegranate juices with different lactic acid bacteria (LAB) on the biotransformation of phenolic compounds. The changes of the antioxidant capacity (AOC) and of LAB growth and survival in different fermented juices were also studied. Two new phenolic derivatives (catechin and α-punicalagin) were identified only in fermented juices. During SGD, the AOC increased together with the phenolic derivatives concentration mainly in the juices fermented with Lactobacillus. These derivatives were formed due to the LAB metabolism of the ellagitannins, epicatechin, and catechin after fermentation and during SGD. The FRAP assay performance might be associated with the degradation and biotransformation of catechin. The fermented pomegranate juices with these LAB increased the bioaccessibility of phenolic compounds, ensuring the survival of LAB after SGD, suggesting a possible prebiotic effect of phenolic compounds on LAB.

Changes in Phenolic Compounds and Phytotoxicity of the Spanish-Style Green Olive Processing Wastewaters by Aspergillus niger B60.

PubMed

Papadaki, Eugenia; Tsimidou, Maria Z; Mantzouridou, Fani Th

2018-05-16

This study systematically investigated the degradation kinetics and changes in the composition of phenolic compounds in Spanish-style Chalkidiki green olive processing wastewaters (TOPWs) during treatment using Aspergillus niger B60. The fungal growth and phenol degradation kinetics were described sufficiently by the Logistic and Edward models, respectively. The maximum specific growth rate (2.626 1/d) and the maximum degradation rate (0.690 1/h) were observed at 1500 mg/L of total polar phenols, indicating the applicability of the process in TOPWs with a high concentration of phenolic compounds. Hydroxytyrosol and the other simple phenols were depleted after 3-8 days. The newly formed secoiridoid derivatives identified by HPLC-DAD-FLD and LC-MS are likely produced by oleoside and oleuropein aglycon via the action of fungal β-glucosidase and esterase. The treated streams were found to be less phytotoxic with reduced chemical oxygen demand by up to 76%. Findings will provide useful information for the subsequent treatment of residual contaminants.

Effect of phenol on the nitrogen removal performance and microbial community structure and composition of an anammox reactor.

PubMed

Pereira, Alyne Duarte; Leal, Cíntia Dutra; Dias, Marcela França; Etchebehere, Claudia; Chernicharo, Carlos Augusto L; de Araújo, Juliana Calabria

2014-08-01

The effects of phenol on the nitrogen removal performance of a sequencing batch reactor (SBR) with anammox activity and on the microbial community within the reactor were evaluated. A phenol concentration of 300 mg L(-1) reduced the ammonium-nitrogen removal efficiency of the SBR from 96.5% to 47%. The addition of phenol changed the microbial community structure and composition considerably, as shown by denaturing gradient gel electrophoresis and 454 pyrosequencing of 16S rRNA genes. Some phyla, such as Proteobacteria, Verrucomicrobia, and Firmicutes, increased in abundance, whereas others, such as Acidobacteria, Chloroflexi, Planctomycetes, GN04, WS3, and NKB19, decreased. The diversity of the anammox bacteria was also affected by phenol: sequences related to Candidatus Brocadia fulgida were no longer detected, whereas sequences related to Ca. Brocadia sp. 40 and Ca. Jettenia asiatica persisted. These results indicate that phenol adversely affects anammox metabolism and changes the bacterial community within the anammox reactor. Copyright © 2014 Elsevier Ltd. All rights reserved.