Ionic Liquid-Microwave-Based Extraction of Biflavonoids from Selaginella sinensis

Abstract

Selaginella sinensis (Desv.) Spring has been used for many years as traditional Chinese medicine (TCM) for many years. Recently, ionic liquids (ILs) have attracted great attentions in extraction and separation technology of TCM as a new green solvent. In this paper, microwave assisted extraction-IL (MAE-IL) that extracted amentoflavone (AME) and hinokiflavone (HIN) from Selaginella sinensis was reported for the first time. The contents of two biflavonoids were simultaneously determined by a high performance liquid chromatography (HPLC) method. After different ionic liquids were compared, it was found [C6mim]BF4 had a high selectivity and efficiency. Moreover, the important extraction conditions, including solid-liquid ratio, IL concentration, extraction time, microwave power and radiation temperature, were also investigated and optimized by response surface methodology (RSM) using AME and HIN yields as index. The results showed that the extraction yields of AME and HIN from S. sinensis were 1.96 mg/g and 0.79 mg/g, respectively, under the optimal process parameters (0.55 mmol/L, 300 W, 40 min, 1:11 g/mL and 48 °C). Compared with the conventional extraction methods, MAE-IL could not only achieve higher yield in shorter time, but also could reduce the consumption of solvent. This effective, rapid and green MAE-IL method was suitable for the extraction of AME and HIN.

Ultrasonic-Assisted Ionic Liquid Extraction of Two Biflavonoids from Selaginella tamariscina

“…The structure of ILs has a great influence on the extraction effect of the active ingredients from natural products. 32 Three different types of ionic liquids are selected, including three benzoxazoles, three imidazoles, and three pyridines, and screened for the extraction of AME and HIN from S. tamariscina ( Figure 4 A–D). It can be seen from the figure that the order of the influence of the three IL types on their extraction effects is pyridines > benzoxazoles > imidazoles, which may be due to the greater interaction between pyridine ILs and biflavonoids, such as hydrogen bonding effect, electrostatic effect, and van der Waals force.…”

Hinokiflavone and Related C–O–C-Type Biflavonoids as Anti-cancer Compounds: Properties and Mechanism of Action

“…HNK is one of the many active compounds that can be found in this type of extract [ 47 ]. Both amentoflavone and HNK can be found in various Selaginella sp., such as S. doederleinii and S. sinensis [ 48 – 50 ]. Anticancer effects have been characterized with different types of Selaginella extracts, in particular with an ethyl acetate extract of S. doederleinii capable of markedly reducing the microvascular density and A549 tumor growth in mice [ 48 , 51 ].…”

Ultrasonic‐Assisted Ionic Liquid Extraction of Four Biflavonoids from Ginkgo biloba L.

“…Ionic liquid (IL), also known as room temperature molten salts, are composed of inorganic or organic anions and organic cations. [11] Therefore, the ionic liquid can be designed. Compared with the traditional solvents, ionic liquids have many excellent properties, such as the wide temperature range, low vapor pressure, strong conductivity, and nonflammability.…”

“…Traditional extraction methods, including reflux extraction, percolation extraction and impregnation extraction, have many disadvantages, such as waste solvent, low extraction efficiency and complicated operation. [11] Therefore, the ultrasonic method was applied to extract biflavonoids from G. biloba L, which was an extraction method employing the cavitation, mechanical and thermal effects of ultrasound to accelerate the release, diffusion and dissolution of target components in the cell, and significantly improve the extraction efficiency. In this experiment, ultrasonic extraction combined with ionic liquid was expected to explore a new extraction method with high efficiency, environmental protection and low energy consumption.…”