Natural Deep Eutectic Solvent-Assisted Extraction, Structural Characterization, and Immunomodulatory Activity of Polysaccharides from Paecilomyces hepiali

Abstract

Polysaccharides, which can be affected by different preparations, play a crucial role in the biological function of Paecilomyces hepiali (PHPS) as a health food. To explore high-valued polysaccharides and reduce the negative influence of human involvement, a green tailorable deep eutectic solvent (DES) was applied to optimize the extraction of polysaccharides (PHPS-D), followed by the evaluation of the structural properties and immunomodulation by comparison with the hot-water method (PHPS-W). The results indicated that the best system for PHPS-D was a type of carboxylic acid-based DES consisting of choline chloride and succinic acid in the molar ratio of 1:3, with a 30% water content. The optimal condition was as follows: liquid–solid ratio of 50 mL/g, extraction temperature of 85 °C, and extraction time of 1.7 h. The actual PHPS-D yield was 12.78 ± 0.17%, which was obviously higher than that of PHPS-W. The structural characteristics suggested that PHPS-D contained more uronic acid (22.34 ± 1.38%) and glucose (40.3 ± 0.5%), with a higher molecular weight (3.26 × 105 g/mol) and longer radius of gyration (78.2 ± 3.6 nm), as well as extended chain conformation, compared with PHPS-W, and these results were confirmed by AFM and SEM. Immunomodulatory assays suggested that PHPS-D showed better performance than PHPS-W regarding pinocytic activity and the secretion of NO and pro-inflammatory cytokines (IL-6, TNF-α and IL-1β) by activating the corresponding mRNA expression in RAW264.7 cells. This study showed that carboxylic acid-based DES could be a promising tailorable green system for acidic polysaccharide preparation and the valorization of P. hepiali in functional foods.

Exploring carbohydrate extraction from biomass using deep eutectic solvents: Factors and mechanisms

“… 148 Paecilomyces hepiali Choline Chloride: Succinic Acid 1:3 85°C, 1.7 h, water content: 30%, L/S = 50 mL/g, water bath Total sugar (12.78%) Wang et al. 149 Pomelo (Citrus grandis (L . ) Osbeck) Choline Chloride: Malonic Acid 1:1 60°C, 2 h, ultrasound Pectin (96.37%) Elgharbawy et al.…”

Efficient Extraction and Purification of Isofraxidin from Acanthopanax Senticosus by DES

“…To extract polyphenols, vanillin, and flavonoids, natural deep eutectic solvents (NADES) and therapeutic deep eutectic solvents (THEDES) were developed in accordance with this principle. NADES are frequently used to improve the biological activity of medications because they are made of primary metabolites including amino acids, carbohydrates, or organic acids through the complexation of HBA and HBD [16][17]. The extract can be used directly in products for human or animal consumption due to the food-grade qualities of its constituent molecules, avoiding the requirement for expensive purifying processes.…”

Structural Characterization and Immunomodulatory Activity of Polysaccharides from Polygonatum sibiricum Prepared with Deep Eutectic Solvents

“…Polysaccharides are commonly extracted by using the pharmacopoeia or the acid (alkali) extraction methods, which are assisted by ultrasound, microwaves, and enzymes. However, there are some inherent limitations in these methods, such as high energy consumption, long extraction time, low extraction efciency, and poor selectivity [1]. Traditional solvents (hot water, acid, and alkali) extract functional components in natural plants though destroying cell walls.…”