Phenols microwave-assisted extraction

Proestos C and Komaitis M 2008. Application of microwave-assisted extraction to the fast extraction of plant phenolic compounds. LWT Food Sci Technol 41(4) 652-659. 

Llompart MP, Lorenzo RA, Cela R, Li K, Belanger JMR, Pare JRJ. Evaluation of supercritical fluid extraction, microwave-assisted extraction and sonication in the determination of some phenolic compounds from various soil matrices. J. Chro-matogr. A 1997 774 243-251. 

Lopez-Avila et al. [7] used microwave assisted extraction to assist the extraction of phenols from soils. 

Lopez-Avila et al. [25] studied the microwave assisted extraction of polyaromatic hydrocarbons, phenols and organochlorine insecticides from standard reference soils and sediments. 

The microwave assisted extraction for organic compounds including polyaromatic hydrocarbons, phenols and organochlorine insecticides, described in section 11.1.8 [25] has been applied to sediments. The application of supercritical fluid extraction to the determination of various insecticides in soils described in section 11.1.7 [23] has been applied to river sediments. 

A nnmber of phenolic snbstances were identified by Sterbova et al. [363] in different plants by a BDS C18 colnmns with 3 pm particle size, and a comparison was carried out on different extraction methods, by the comparison of microwave-assisted extraction (MAE) to the traditional approach. 

Gallo M. Ferracane R. Graziani G. Ritieni A. Fogliano V. 2010. Microwave assisted extraction of phenolic compounds from four different spices. Molecules 15 6365-6374. 

Hayat K. Hussain S. Abbas S. Farooq U. Ding B. Xia S. Jia C. Zhang X. Xia W. 2009. Optimized microwave-assisted extraction of phenolic acids from citrus mandarin peels and evaluation of antioxidant activity in vitro. Sep. Purif. Technol. 70 63-70. 

Liazid, A. Palma, M. Brigui, J. Barroso, C.G. 2007. Investigation on phenolic compounds stability during microwave-assisted extraction. J. Chromatogr. A. 1140 29-34. 

A study was carried out for LEE by the Soxhlet method and microwave-assisted extraction for the determination of the priority phenols in soil samples. Recoveries varied from 67 to 97% with RSD between 8 and 14% for LEE, and >70% for the MAP, except for nitrophenols that underwent degradation when the latter method was applied. LOD was from 20 ngg for 2,4-dimethylphenol to 100 ngg for pentachlorophenol. The best detection method for EC was atmospheric pressnre chemical ionization MS (APCI-MS). The most abnndant ions obtained by this detection method were [M — H] for the lowly chlorinated phenols and [M — H — HCl] for tri-, tetra- and pentachlorophenols . 

As indicated in the previous sections, the antioxidant content in plastic material is often determined by chromatographic methods. Another widely used technique for polymer characterization is thermal analysis with differential scanning calorimetry (DSC). When the oxygen induction time (OIT) for a sample containing a phenoHc antioxidant is measured, a significant oxidative exothermic response is obtained in the DSC when all the phenolic antioxidant in a sample is consumed. The OIT is thus directly related to the antioxidant content in the material and to the stabihzing function, i.e. the antioxidant efficiency in the sample, if the consumption of phenolic antioxidants obeys zero-order kinetics at the temperature used [44]. Table 1 shows the amount of the antioxidant Irganox 1081 in polyethylene (PE) determined by HPLC and extraction by microwave assisted extraction (MAE),... 

The examples described in this section 10.6.1 constituted the first report ever of ill situ reaction-extraction work involving foodstuffs. We had reported earlier on a related approach in a different field, namely a derivatisation-extraction procedure whereby phenols and methylated phenols were acetylated-extracted from environmental matrices in a one-step MAP procedure (15). The latter procedure, however, was performed under much harsher conditions that could not be used with foodstuffs where the potential of creating artefacts is a prime concern. This approach of one-pot, multiple-step procedures opens the avenue to numerous applications of direct interest to the food analysts and are especially versatile and valuable when using microwave-assisted extraction performed in open-vessel systems. This, along with solvent-less extraction (such as MAP gas-phase applications ) is believed... 

Figure 3 Experimental design for continuous MAE, liquid-liquid extraction, sorption/cleanup of phenol compounds in soil samples. IV, injection valve PS, membrane phase separator o.p. and a.p., organic and aqueous phases W, waste. (Reproduced with permission from Ericsson M and Colmsjo A (2000) Dynamic microwave-assisted extraction. Journal of Chromatography 877 141 Elsevier.)...

Most of the extraction techniques of phenolic compounds from vegetables are based on ultrasound-assisted extraction (UAE) [27,44,45], In addition, other techniques have been successfully applied to the pretreatment of phenolic compounds in fruits and vegetables, including pressurized liquid extraction (PLE) [46], solid-phase extraction (SPE) [47], supercritical fluid extraction (SFE) [48], microwave-assisted extraction (MAE) [49], rotary shaker-assisted extraction (RAE), [50] and QuEChERS (acronym of quick, easy, cheap, effective, rugged and safe) [51], as can be observed in Tables 16.3 and 16.4. In some cases, an acid treatment [52] was applied to hydrolyze the glycosides in order to determine the content of free and conjugated flavonoids as aglycons. 

Li, H., Deng, Z., Wu, T., Liu, R., Loewen, S., and Tsao, R. 2012. Microwave-assisted extraction of phenolics with maximal antioxidant activities in tomatoes. Food Chem. 130 928-936. 

Zhang Z, Lv G, Pan H, Fan L (2012) Optimisation of the microwave-assisted extraction process for six phenolic compounds in Agaricus blazei murrill. Int J Food Sci Technol 47(1) 24-31... 

Song J, Li D, Liu C, Zhang Y (2011) Optimized microwave-assisted extraction of total phenolics (TP) fimn Ipomoea batatas leaves and its antioxidant activity. Innov Food Sci Emerg Technol 12(3) 282-287... 

Ballard TS, MalUkarjunan P, Zhou K, O Keefe S (2010) Microwave-assisted extraction of phenolic antioxidant compounds from peanut skins. Food Chem 120(4) 1185-1192... 

Hong N, Yaylayan VA, Raghavan GSV, Pare JRJ, Belanger JMR (2001) Microwave-assisted extraction of phenolic compounds from grape seed. Nat Prod Lett 15(3) 197-204... 

When microwave assisted extraction of phytochemicals from grape skins was compared to conventional extraction methods, the former method lowered the efficiency of the extraction and altered the profile of the phytochemicals extracted (Peralbo-Molina et al. 2012). Another study on the extraction of phenolic compounds from wine leaves reported a shorter extraction time using microwave assisted extraction (Perez-Serradilla and Luque de Castro 2011). Although it has been shown that using electromagnetic radiation can improve the extraction of phenolic compounds from other plants (Li et al. 2004), the limited number of studies conducted on the microwave assisted extraction of phytochemicals from grapes has not yet demonstrated a clear benefit of this method. 

Perez-Serradilla, J.A. and Luque de Castro, M.D. 2011. Microwave-assisted extraction of phenolic compounds from wine lees and spray-drying of the extract. Food Chemistry, 72- (4) 1652-1659. 

Patsias, J., Papadakis, E. N., and Papadopoulou-Mourkidou, E., Analysis of phenoxyalkanoic acid herbicides and their phenolic conversion products in soil by microwave assisted solvent extraction and subsequent analysis of extracts by online SPE-liquid chromatography, J. Chromatogr. A, 959, 153-161, 2002. 

Sharma U, Sharma K, Sharma N, Sharma S, Singh HP, Sinha AK, Microwave-assisted efficient extraction of different parts of hippophae rhamnoides for the comparative evaluation of antioxidant activity and quantification of its phenolic constituents by reverse-phase high-performance liquid chromatography (RPHPLC), J. Agric. Food Chem. 2008 56 374-379. 

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