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Niekonwencjonalne metody ekstrakcji : ekstrakcja ekologiczna

Nowosad Karolina, Sujka Monika

Wiadomości Chemiczne

2019

[Z] 73, 9-10

465--479

Extraction is a method of extracting a chemical from a solution or mixture of solid substances. Conventional methods of extraction, for example, Soxhlet method, require the use of hazardous solvents, are time-consuming and cause degradation of the extracted compounds. Green extraction is characterized by the speed, it gives a quantitative recovery of the extract and does not cause degradation of the components. It takes place at a lower energy consumption than conventional extraction. A number of novel alternatives to conventional extraction techniques have been proposed, including ultrasonic assisted extraction (UAE), supercritical fluid extraction (SFE), enzyme extraction or pulsed electric field. These techniques allow to reduce or eliminate the use of toxic solvents, improve process efficiency and extract quality. The temperature of the above-mentioned processes is low, which affects the behavior of temperature-sensitive substances. The widely used "green extraction" is SFE - extraction with supercritical fluid. The solvent is a supercritical fluid, most often carbon dioxide. Ultrasonic extraction is environmentally friendly, easy to use, versatile and relatively cheap compared to other innovative techniques. This technique can be used to extract, for example, polysaccharides, essential oils, proteins, peptides, dyes, pigments and bioactive substances. Extraction with the use of pulsed electric field is used to extract mainly polyphenols and other bioactive components. Extraction with enzymes (mainly pectinases, cellulases and hemicellulases) is widely used in the food industry, eg for clarifying beer and juices. The extraction yield depends on the solvent system, temperature, enzyme function, substrate availability and pH.

Rapid protein extraction method using ultrasound probe sonication for metal bound protein molecular weight screening in vegetal tissues

Pedredo Z., Madrid Y., Camara C.

Chemia i Inżynieria Ekologiczna

2005

Vol. 12, nr 5-6

573-586

A fast, reliable and simple protein disruption method for metals (Cu, Ni, Co and Zn) bound protein molecular weight characterization in vegetal tissues is described. The method is based on the application of ultrasound probe sonication (USP) and was compared with the traditional and most widely used, grinding disruption method. The resulting cell lysates were characterized by size exclusion chromatography coupled to UV and inductive coupled plasma mass spectrometry. The most efficient extraction conditions were found to be 20 s sonication time at a frequency of 20 kHz without need of using protease inhibitor. The proposed method was proved to be efficient and fast for the disruption of vegetal tissues and could be considered as an alternative to conventional sample treatment for metal bound protein molecular weight screening and metal speciation studies in vegetal tissues.

Opisano szybką, prostą i wiarygodną metodę degradacji białek zawierających metale Cu, Ni, Co i Zn, a pochodzących z tkanek roślinnych, które scharakteryzowano poprzez pomiar masy molekularnej. W tym celu wykorzystano ultradźwięki (technikę USP) i sposób ten porównano z tradycyjną metodą degradacji poprzez mechaniczne rozcieranie. Lizat komórkowy charakteryzowano za pomocą chromatografii wykluczającej z detekcją UV oraz ICP-MS. Największe wydajności ekstrakcji uzyskiwano przy sonif1kacji w czasie 20 s przy częstotliwości 20 kHz bez dodatku inhibitora proteazy.