Deep Eutectic Solvents: Alternative Solvents for Biomass-Based Waste Valorization

Abstract

Innovative technologies can transform what are now considered “waste streams” into feedstocks for a range of products. Indeed, the use of biomass as a source of biopolymers and chemicals currently has a consolidated economic dimension, with well-developed and regulated markets, in which the evaluation of the manufacturing processes relies on specific criteria such as purity and yield, and respects defined regulatory parameters for the process safety. In this context, ionic liquids and deep eutectic solvents have been proposed as environmentally friendly solvents for applications related to biomass waste valorization. This mini-review draws attention to some recent advancements in the use of a series of new-solvent technologies, with an emphasis on deep eutectic solvents (DESs) as key players in the development of new processes for biomass waste valorization. This work aims to highlight the role and importance of DESs in the following three strategic areas: chitin recovery from biomass and isolation of valuable chemicals and biofuels from biomass waste streams.

Deep eutectic solvent-ultrasound assisted extraction as a green approach for enhanced extraction of naringenin from Searsia tripartita and retained their bioactivities

“…Because of its greater electrostatic interaction with flavonoids than the other DESs, DES-1 demonstrated better extraction efficiency than the others ( 40 ). Moreover, formic acid and choline chloride, which exist naturally in many whole foods, are totally safe to ingest ( 41 ). The DES system (DES-1) composed of choline chloride and formic acid was used in the following investigations.…”

“…As previously mentioned, the molar ratio of HBD to HBA in the DES regulates the interaction of hydrogen bonding, which in turn influences the viscosity of the DES ( 42 ). The physical properties of DES also have an impact on the efficiency with which NA is extracted ( 41 , 42 ). We did not attempt to increase the choline chloride level since DES crystallizes at a molar ratio greater than 3.5:1.…”

Chitin extraction from crab shells by two-step fermentation with Lacticanttacllus pantarum and Pseudomonas aeruginosa

“…However, these two methods are still at the start of chitin extraction, more attention should be paid in the future to explore limiting factors (stability, recovery rate, security, etc.) (Rachiero et al 2022). Microorganisms are important sources of enzymes, and a variety of bacteria are able to produce organic acids during the growth process, which can be exploited in the DM and DP process when extracting chitin from shrimp and crab shell wastes, which is called microbiological method.…”

A New Method of Extracting Polygonatum sibiricum Polysaccharide with Antioxidant Function: Ultrasound-Assisted Extraction-Deep Eutectic Solvents Method

“…Thus, DESs present a unique advantage, such as safety, easy manipulation, and removement, in the extraction and separation of natural plants [ 23 ]. As an economical and innovative green solvent, they have been widely applied in the separation, extraction, and synthesis of food industries, based on the above characteristics [ 19 , 24 ]. Tang [ 25 ] once adopted DESs to extract PsP, which extraction yield could reach 33.81%.…”