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Ultrasound-assisted Extraction (ultrasound-assisted + extraction)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

An improved ultrasound-assisted extraction process of gossypol acetic acid from cottonseed soapstock

AICHE JOURNAL, Issue 3 2009
Guangfeng Jia
Abstract To investigate the extracted process of gossypol acetic acid (G-AA) from cottonseed soapstock and explore the improvement of its yield and purity, a novel ultrasound-assisted extraction and crystallization method was introduced to this process. Under the optimized conditions, preliminary G-AA with the yield of 1300 mg and the purity of 95.9% could be obtained from 100 g of fresh soapstock by ultrasound-assisted extraction. In addition, UV, IR, and NMR spectrum further confirmed the detailed chemical structure of G-AA. Assay of inhibiting human prostate tumor cell line PC-3 and human breast cancer cell line MDA-MB-231 revealed its biological activity, the values of IC50 are 9.096 ,mol/L and 14.37 ,mol/L respectively. In comparison with the conventional solvent extraction, this novel process increases the content of G-AA over 90%, reduces the time of crystallization by 75%, and retains the anticancer activity of gossypol. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source]

Determination of pentachlorophenol and tribromophenol in sawdust by ultrasound-assisted extraction and MEKC

JOURNAL OF SEPARATION SCIENCE, JSS, Issue 6-7 2008
Claudia Mardones
Abstract An ultrasonic bar-assisted extraction and CE separation procedure for the determination of pentachlorophenol (PCP) and 2,4,6-tribromophenol (TBP) residues in sawdust was developed and applied. For this purpose, micellar electrokinetic capillary chromatography (MEKC) was used and compared with a GC/MS methodology. This methodology allowed the quantification of PCP and TBP in a concentration range of 2.5,12.0 mg/kg for TBP and 2.8,12.0 mg/kg for PCP. Different sample treatment processes were evaluated in order to extract these compounds from sawdust. Better results were obtained when the residues were extracted with ultrasound-assisted hexane, filtered, evaporated, dissolved in Na2CO3, and injected into the CE equipment. The optimal option for GC/MS was extraction with Na2CO3 followed by a derivation using acetic anhydride and liquid,liquid extraction with hexane. This method allowed the quantification of TBP and PCP in sawdust in a concentration range of 0.19,12.00 mg/kg and 0.14,12.00 mg/kg, respectively. The CE method was compared with the GC/MS as reference method. The results were shown to be statistically similar by both methods for PCP as well as for TBP. [source]

RP-HPTLC densitometric determination and validation of vanillin and related phenolic compounds in accelerated solvent extract of Vanilla planifolia,*

JOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2007
Upendra Kumar Sharma
Abstract A simple, fast and sensitive RP-HPTLC method is developed for simultaneous quantitative determination of vanillin and related phenolic compounds in ethanolic extracts of Vanilla planifolia pods. In addition to this, the applicability of accelerated solvent extraction (ASE) as an alternative to microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and Soxhlet extraction was also explored for the rapid extraction of phenolic compounds in vanilla pods. Good separation was achieved on aluminium plates precoated with silica gel RP-18 F254S in the mobile phase of methanol/water/isopropanol/acetic acid (30:65:2:3, by volume). The method showed good linearity, high precision and good recovery of compounds of interest. ASE showed good extraction efficiency in less time as compared to other techniques for all the phenolic compounds. The present method would be useful for analytical research and for routine analysis of vanilla extracts for their quality control. [source]

Selective ultrasound-assisted extractions of lipophilic constituents from Betula alleghaniensis and B. papyrifera wood at low temperatures

PHYTOCHEMICAL ANALYSIS, Issue 4 2007
J.-M. Lavoie
Abstract Betula alleghaniensis and B. papyrifera are widely distributed in the province of Québec (Canada) and, since these trees are valuable exports for the local lumber industry, large amounts of their residual ligneous biomass are available for further exploitation. Betula species are well known for their significant concentrations of triterpenes, some of which were recently discovered to present promising bioactivity. The secondary transformation of birch biomass could therefore become important for many industries, particularly the pharmaceutical industry. In the present study, extracts from birch sawdust were obtained using an optimised ultrasound-assisted extraction in which the careful choice of temperature permitted a selective extraction of the targeted triterpenes. Moreover, compared with the classical Soxhlet method, higher extraction yields were obtained in a shorter time. The lipophilic extracts obtained using dichloromethane as a solvent were analysed by GC-MS and the major compounds identified as lupane-type cyclic triterpenoids accompanied by the non-cyclic triterpene squalene. Numerous aliphatic long-chain fatty acids were also found in the extracts together with phytosterols. Betulonic acid and squalene, the major extract constituents for both B. alleghaniensis and B. papyrifera, are both bioactive molecules. Copyright © 2007 John Wiley & Sons, Ltd. [source]