Polysaccharides from waste Zingiber mioga leaves: Ultrasonic-microwave-assisted extraction, characterization, antioxidant and anticoagulant potentials

Ultrasonic-assisted extraction of polysaccharide from Paeoniae Radix alba: Extraction optimization, structural characterization and antioxidant mechanism in vitro

Paeoniae Radix alba is used in Traditional Chinese Medicine for the treatment of gastrointestinal disorders, immunomodulatory, cancer, and other diseases. In the current study, the yield of Paeoniae Radix alba polysaccharide (PRP) was significantly increased with optimal ultrasound-assisted extraction compared to hot water extraction. Further, an acidic polysaccharide (PRP-AP) was isolated from PRP after chromatographic separation and was characterized as a typical pectic polysaccharide with side chains of arabinogalactans types I and II. Moreover, it showed antioxidant effects on LPS-induced damage on IPEC-J2 cells determined by qRT-PCR and ELISA, including decreasing the pro-inflammatory factors' expressions and increasing the antioxidant enzymes activities, which was shown to be related to the Nrf2/Keap1 pathway modulated by PRP-AP. The metabolites change (such as itaconate, cholesterol sulfate, etc.) detected by untargeted metabolomic analysis in cells was also shown to be modulated by PRP-AP, and these metabolites were further utilized and protected cells damaged by LPS. These results revealed the cellular active mechanism of the macromolecular PRP-AP on protecting cells, and supported the hypothesis that PRP-AP has strong benefits as an alternative dietary supplement for the prevention of intestinal oxidative stress by modulating cellular metabolism.

Ultrasonic-Assisted Decoloration of Polysaccharides from Seedless Chestnut Rose (Rosa sterilis) Fruit: Insight into the Impact of Different Macroporous Resins on Its Structural Characterization and In Vitro Hypoglycemic Activity

Pigments within polysaccharides pose significant challenges when analyzing their structural characteristics and evaluating their biological activities, making decolorization a crucial step in purifying these biomolecules. In this research, a novel approach using ultrasound-assisted static adsorption with macroporous resins was employed to decolorize polysaccharides extracted from seedless chestnut rose (Rosa sterilis S. D. Shi) fruit (RSP). Among the fourteen tested resins, AB-8, D101, D4020, HPD100, and S8 were identified as the most effective, demonstrating superior decoloration efficiency and polysaccharide recovery. Further examinations of RSPs treated with these five resins revealed distinct effects on their uronic acid levels, monosaccharide makeup, molecular weight, surface structure, and hypoglycemic properties. The RSP treated with HPD100 resin stood out for having the highest uronic acid content, smallest particle size, and lowest molecular weight, leading to the most notable inhibition of α-glucosidase activity through a mixed inhibition model. The application of HPD100 resin in the decolorization process not only potentially preserved the macromolecular structure of RSP but also enhanced its hypoglycemic efficacy. These findings provide a solid theoretical basis for further exploring RSP as a component of functional foods, underscoring the effectiveness of the ultrasound-assisted resin adsorption method in polysaccharide purification.

Structural Characterization and Antioxidant Activity of β-Glucans from Highland Barley Obtained with Ultrasonic-Microwave-Assisted Extraction

In order to efficiently extract β-glucan from highland barley (HBG) and study its structural characterization and antioxidant activity, ultrasonic-microwave-assisted extraction (UME) was optimized by the response surface method (RSM). Under the optimal extraction conditions of 25.05 mL/g liquid-solid ratio, 20 min ultrasonic time, and 480 W microwave intensity, the DPPH radical scavenging activity of HBG reached 25.67%. Two polysaccharide fractions were purified from HBG, namely HBG-1 and HBG-2. Structural characterization indicated that HBG-1 and HBG-2 had similar functional groups, glycosidic linkages, and linear and complex chain conformation. HBG-1 was mainly composed of glucose (98.97%), while HBG-2 primarily consisted of arabinose (38.23%), galactose (22.01%), and xylose (31.60%). The molecular weight of HBG-1 was much smaller than that of HBG-2. Both HBG-1 and HBG-2 exhibited concentration-dependent antioxidant activity, and HBG-1 was more active. This study provided insights into the efficient extraction of HBG and further investigated the structure and antioxidant activities of purified components HBG-1 and HBG-2. Meanwhile, the results of this study imply that HBG has the potential to be an antioxidant in foods and cosmetics.

Sulfation on polysaccharides from Zizania latifolia extracted using ultrasound: Characterization, antioxidant and anti-non-small cell lung cancer activities

Zizania latifolia is a highly nutritious vegetable being praised as "Ginseng in Water". Polysaccharides are the main bioactive ingredients in Z. latifolia, but there have been no reports on the yield- and activity-guided ultrasonic-assisted extraction (UAE), sulfation and anti-non-small cell lung cancer (NSCLC) activity. In this study, Z. latifolia polysaccharides (ZLP) were extracted using UAE under an optimized power, followed by sulfation to give three derivatives (SZLP-1 ∼ 3). After characterization, the antioxidant and anti-NSCLC activities were evaluated. The optimal ultrasonic power for ZLP extraction was screened out to be 300 W, under which the yield was 16.9 ± 2.10 %, and the scavenging rate against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical was 63.3 ± 5.71 %, significantly higher than those of other powers and hot-water extraction. A series of characterizations fully confirmed the sulfated modification of ZLP. Sulfation improved the antioxidation of ZLP and was positively proportional to the degree of substitution (DS), of which SZLP-2 with a DS of 15.1 ± 2.50 elicited strong hydroxyl and DPPH radicals-scavenging capacities. Meanwhile, SZLP-2 also exerted promising anti-NSCLC potency via inhibiting A549 cell proliferation, with a median inhibition concentration (IC50) of 0.57 ± 0.01 mg/mL at 72 h, markedly smaller than that of unmodified ZLP (0.78 ± 0.04 mg/mL). In summary, the yield- and activity-guided UAE led to the ZLP with high yield and strong antioxidation. Further sulfation enhanced the bioactivities and produced the promising SZLP-2, which showed great potential in the development of novel antioxidant and anti-NSCLC drug.