Polysaccharides from Nitraria retusa Fruit: Extraction, Purification, Structural Characterization, and Antioxidant Activities

Abstract

Polysaccharides are important bioactive components of Nitraria retusa fruit (NRF). In this study, the ultrasonic-assisted extraction (UAE) conditions of polysaccharides from Nitraria retusa fruit (NRFPs) were optimized by response surface methodology (RSM). The structural characteristics and antioxidant activity were investigated. The maximum NRFPs yield of 3.35% was obtained under the following optimal conditions: temperature of 59.5 °C, time of 30.5 min, liquid-to-solid ratio of 19.5 mL/g. Three polysaccharide fractions, NRFP-1 (20.01 kDa), NRFP-2 (28.96 kDa), and NRFP-3 (67.45 kDa), were isolated. Glucose, galactose, and arabinose in different percentages were identified as the primary monosaccharide units. The Fourier transform infrared spectrometer (FT-IR) and nuclear magnetic resonance (NMR) analysis indicated the presence of α- and β-glycosidic bonds in NRFPs. The NRFP-3 exhibited the highest scavenging activities against DPPH, ABTS, -OH free radicals, and Fe+3-reducing activity.

Exploring the Effects of Short-Term Daily Intake of Nitraria retusa Tea on Lipid Profile: A Pre-Post, Uncontrolled Pilot Study in Both Healthy and Overweight/Obese Adults

“…Furthermore, the antihypertensive effect of NRE is not well explored. In fact, few studies mentioned that the fruits and leaves of Nitraria have been used as a nutritional food and traditional herb for the treatment of hypertension and abnormal menstruation [ 19 , 24 ]. Further studies should be conducted to explore the antihypertensive effect of the infusion of crushed, dried leaves of Nitraria retusa in overweight/obese participants with elevated blood pressure levels (systolic blood pressure (SBP) ≥ 140 mmHg and/or diastolic blood pressure (DBP) ≥ 90 mmHg).…”

Optimization of Composite Enzymatic Extraction, Structural Characterization and Biological Activity of Soluble Dietary Fiber from Akebia trifoliata Peel

“…The purified AP-SDF contained a high uronic acid content (34.90 %) and a total sugar content of 52.46 %. Despite the removal of soluble proteins by the Sevag method in this study, a low quantity of proteins (8.33 %) was also found, indicating that AP-SDF was an acidic polysaccharide and the existence of minor polysaccharideprotein complexes, which often exhibit favorable bioactivities [40]. As shown in Table 4 and Figure 3A, AP-SDF is mainly composed of arabinose (36.03 %), galacturonic acid (27.40 %), and glucose (19.00 %), respectively, with fucose, rhamnose, galactose, xylose, mannose and glucuronic acid as minor components.…”

“…The absorption peaks at 1050.83 cm −1 and 1018.55 cm −1 are attributed to C-O-H and C-O-C stretching vibrations of the pyranose ring [10]. The weak peaks at 831.55 cm -1 and 638.79 cm -1 indicate that the configuration of AP-SDF is dominated by α-glycosidic bonds [40].…”

Preparation, Properties and Application in Electrospinning of Tremella Polysaccharide–Protein Complex

“…DPPH free radical scavenging rate test is one of the important indexes to determine the antioxidant capacity of samples, which is widely used in the study of antioxidant capacity of natural products, food, health products, and drugs [ 25 ]. Figure 2 is the DPPH free radical scavenging ability of the complex of tremella polysaccharide and three proteins under different proportions, time, temperature, and pH conditions.…”