Use of Liquefied Dimethyl Ether for the Extraction of Proteins from Vegetable Tissues

Abstract

Dimethyl ether (DME), the simplest ether with the formula CH 3 OCH 3 , is a low-temperature solvent and extraction agent applicable to specialized laboratory procedures as recently demonstrated for extraction of biologically active, flavoring or pungent organic compounds from some biological materials. Due to its low boiling point, DME facilitates the removal of solvent from the samples after extraction. In the present study, we demonstrated the extraction of proteins from juicy or relatively dry vegetable tissues and the distribution of proteins in the dry phase and separated aqueous phase were compared. It is notable that a series of proteins from carrot roots, sized between 84.7 and 33.1 kDa, were detected in the liquid sample extracted by DME, suggesting that DME could be used as an effective extraction solvent for separating the hydrophilic (water soluble) proteins from the crude protein samples. Extraction of water-soluble proteins largely depends on the de-watering action of DME.

Dewatering and Extraction of Hydrophilic Solutes and Essential Oils from Cryo-preserved Lemon Peels Using Liquefied Dimethyl Ether

“…As previously demonstrated [12], liquefied DME can be used as a dewatering solvent actively removing water from plant tissues, therefore, in the present study, we further demonstrated that dewatering and extraction of industrially important components can be achieved in one step under cryogenic conditions.…”

“…As discussed in our earlier work [12], the low boiling point (-23°C) for DME could be highly beneficial in order to facilitate the removal of the solvent (DME) from the extracted water-containing samples. We have previously demonstrated that, with liquefied DME, extraction of watersoluble proteins from water-containing plant materials such as vegetable tissues can be achieved [12]. The extraction efficiency of water-soluble proteins largely depends on the dewatering action of DME.…”

“…However, in order to prevent the degradation of biologically active components in plant materials, the dewatering process should be carried out at low temperature as discussed elsewhere [12]. Therefore, in the present study, we attempted to develop a simple protocol for effectively achieving dewatering and extractions of essential oils (EOs), citric acid (CA), and ascorbate (vitamin C, VC) at the same time, from frozen lemon peel tissues, used as model plant tissues, by incubating the frozen tissues in the liquefied DME under cryogenic conditions (at -30°C).…”

Extraction and Separation of Natural Products from Microalgae and Other Natural Sources Using Liquefied Dimethyl Ether, a Green Solvent: A Review

“…Moreover, liquefied DME has been used to extract bioactive compounds from citrus leaves and peels (citrus flavonoids) [197], Garcinia mangostana Linn (mangostin) [198], vegetables (proteins) [199], lemon peel tissue (citric acid, vitamin C, and essential oils) [200], tuna liver (fish oil, n-3 polyunsaturated fatty acids) [201,202], macroalgae Monostroma nitidum (Lutein) [203], Japanese knotweed rhizomes (resveratrol and glycoside) [204], Centella asiatica leaves (triterpenoid) [205], hops (α-acids and β-acids) [206], cyanobacteria (fatty acids) [207], sugar mill waste (policosanol and phytosterol) [208], Curcuma longa L. (curcumin) [138], and diatom Chaetoceros simplex var. calcitrans (fucoxanthin) [178] (Figure 5).…”

Subcritical dimethyl ether extraction as a simple method to extract nutraceuticals from byproducts from rice bran oil manufacture

“…DME has been authorized by the European Food Safety Authority as a safe extraction solvent to produce foodstuffs and food ingredients 20 . Apart from its application as a fuel, subcritical DME has been used for biologically active, flavoring or pungent organic compounds from spices (ginger, black pepper, and chili powder), and its effectiveness is comparable with supercritical carbon dioxide 21 . Most studies on SUPFE have focused on the extraction yield, pressure, temperature, flow rate, and time, but did not focus on the purity of bioactive compounds extracted from SUPFE.…”