Optimization of ultrasonic-assisted extraction of polysaccharides from Hemerocallis citrina and the antioxidant activity study

Optimization of enzyme-assisted microwave extraction, structural characterization, antioxidant activity and in vitro protective effect against H2O2-induced damage in HepG2 cells of polysaccharides from roots of Rubus crataegifolius Bunge

In this study, an enzyme-assisted microwave extraction process was obtained by response surface method of polysaccharide from roots of Rubus crataegifolius Bunge. The optimized extraction process was as follow: enzyme dosage 2 %, enzymatic time was 3.6 h, enzymatic pH 4.9, and microwave time 4.7 min, with the extraction yield of 9.07 %. Four homogeneous polysaccharides (RCP-1, RCP-3, RCP-4 and RCP-5) were purified through column chromatography. Four polysaccharides have the relative higher molecular weights of 1.70 × 106 Da, 5.56 × 106 Da, 4.97 × 106 Da, and 9.80 × 106 Da and mainly consisted of GluN, GluA, Glu, Gal and Arab. FT-IR and NMR spectral analysis confirmed that the purified polysaccharides were polypyranose containing α- and β-glycosidic bonds. RCP - 1 has a relative high crystallinity. Four purified polysaccharides contained triple helical conformations, and have good antioxidant activities. Among the purified polysaccharides, RCP - 1 was found to reduce the oxidative cell damage induced by H2O2 through increasing of cell viability, inhibition of AST and ALT levels, ROS production and cell apoptosis, increasing of the activities of antioxidative enzymes, as well as reduction of MDA content. Our findings would provide a foundation for purified polysaccharides efficient extraction and demonstrated that the polysaccharides from R. crataegifolius roots could be a promising hepatoprotective agent.

Ultrasonic high-yield extraction of non-toxic fucose-containing Abroma augusta polysaccharide bearing emulsifying properties

BACKGROUND

The stem of Abroma augusta contains mucilaginous polysaccharides having numerous ethnomedicinal properties. The present work aimed to develop a scalable ultrasonic-assisted aqueous Abroma augusta mucilage (AAM) extraction (UAE) method and further explores its emulsifying property and toxicity concern.

RESULTS

The combination of ultrasonic power (750 W), solid-to-liquid ratio (1:15) and temperature (348 K) gave the highest extraction yield of 2.28% with a diffusivity value of 3.85 × 10-9 m2 s-1, which was higher than aqueous extraction method using a kinetic model based on Fick's second law of diffusion. The extracted polysaccharide showed no toxicity as measured through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assay on RAW cell line. Additionally, the polysaccharide over its critical micelle concentration (400, 500, 600 and 700 μg mL-1) offered emulsifying properties with 0.5%, 1% and 5% oil (v/v). The emulsion with a polysaccharide concentration of 600 μg mL-1 with 5% oil (v/v) provides stability against coalescence for 3 days.

CONCLUSION

The overall findings indicated that UAE of AAM polysaccharide can be used for an efficient extraction method, and the obtained polysaccharide is nontoxic in nature and bears emulsifying properties. © 2024 Society of Chemical Industry.

A Novel Water-Soluble Polysaccharide from Daylily (Hemerocallis citrina Baroni): Isolation, Structure Analysis, and Probiotics Adhesion Promotion Effect

The daylily (Hemerocallis citrina Baroni) flower is a traditional raw food material that is rich in a variety of nutrients. In particular, the content of polysaccharides in daylily is abundant and has been widely used as a functional component in food, cosmetics, medicine, and other industries. However, studies on the structure-effective relationship of daylily flower polysaccharides are still lacking. In view of this, daylily flower polysaccharides were isolated and purified, and their physical and chemical properties, structure, antioxidant activity, and adhesion-promoting effect on probiotics were evaluated. The results showed that a novel water-soluble polysaccharide (DPW) with an average molecular weight (Mw) of 2.224 kDa could be successfully isolated using column chromatography. Monosaccharide composition analysis showed that DPW only comprised glucose and fructose, with a molar ratio of 0.242:0.758. Through methylation and nuclear magnetic resonance (NMR) analysis, it was inferred that DPW belonged to the fructans group with a structure of α-D-Glcp-1→2-β-D-Fruf-1→(2-β-D-Fruf-1)n→. Antioxidant analysis showed that DPW showed strong 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-Oxide (PTIO-scavenging activity with IC50 of 1.54 mg/mL. DPW of 1.25 to 5 mg/mL could significantly increase the adhesion rate of Lactobacillus acidophilu, Lactobacillus casei, Bifidobacterium adolescentis, and Lactobacillus plantarum on Caco-2 cells. Considering the above results, the present study provides a theoretical basis and practical support for the development and application of daylily polysaccharides as a functional active ingredient.

Ultrasonic-Assisted Extraction, Structural Characteristics, and Antioxidant Activities of Polysaccharides from Alpinia officinarum Hance

Alpinia officinarum Hance, a well known agricultural product in the Lei Zhou peninsula, is generally rich in polysaccharides. In order to enhance the use of A. officinarum Hance polysaccharides (AOP) in functional food, AOP was extracted using an ultrasonic-assisted extraction method, and the ultrasonic extraction parameters of AOP was optimized. Furthermore, this study investigated the physicochemical and antioxidant activities of AOPs. In addition, the structural properties were preliminarily determined using Fourier-transform infrared spectroscopy (FTIR), high performance size exclusion chromatography, and a Zetasizer. Ultimately, this study explored the mechanism underlying the antioxidant activities of AOP. The results showed that the optimal ultrasonic-assisted extraction parameters were as follows: ultrasonic time, 6 min; ratio of water to material, 12 mL/g; and ultrasonic power, 380 W. Under these conditions, the maximum yield of AOPs was 5.72%, indicating that ultrasonic-assisted extraction technology is suitable for extracting AOPs due to the reduced time and water usage. Additionally, AOPs were purified using graded alcohol precipitation, resulting in three fractions (AOP30, AOP50, and AOP70). AOP30 had the lowest molecular weight of 11.07 kDa and mainly consisted of glucose (89.88%). The half inhibitory concentration (IC50) value of AOP30 and AOP70 was lower than that of AOP50 in the ability to scavenge the ABTS radical, while a reverse trend was observed in reducing ferric ions. Notably, the antioxidant activities of AOPs were highly correlated with their polydispersity index (Mw/Mn) and Zeta potential. AOP30, a negatively charged acidic polysaccharide fraction, exhibited electron donating capacities. Additionally, it displayed strong antioxidant abilities through scavenging 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radicals and reducing ferric ions. In conclusion, the present study suggests that AOP30 could be developed as an antioxidant ingredient for the food industry.

Polysaccharides from Hemerocallis citrina Baroni Inhibit the Growth of Hepatocellular Carcinoma Cells by Regulating the Wnt/β-Catenin Pathway

Hemerocallis citrina Baroni is an edible plant with anti-inflammatory, antidepressant, and anticancer activities. However, studies on H. citrina polysaccharides are limited. In this study, a polysaccharide named HcBPS2 was isolated and purified from H. citrina. Monosaccharide component analysis showed that HcBPS2 was composed of rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid. Notably, HcBPS2 significantly inhibited human hepatoma cell proliferation, but had little effect on human normal liver cells (HL-7702). Mechanism investigations indicated HcBPS2 suppressed human hepatoma cell growth through the induction of G2/M phase arrest and mitochondria-dependent apoptosis in human hepatoma cells. In addition, the data revealed that HcBPS2 treatment led to the inactivation of Wnt/β-catenin signaling, which then gave rise to cell cycle arrest and apoptosis in human hepatoma cancer cells. Collectively, these findings suggested that HcBPS2 may serve as a therapeutic agent against liver cancer.

Isolation, structural and bioactivities of polysaccharides from Anoectochilus roxburghii (Wall.) Lindl.: A review

Anoectochilus roxburghii (Wall.) Lindl. (A. roxburghii), a valuable herbal medicine in China, has great medicinal and edible value. Polysaccharides, as one of the main active components of A. roxburghii, comprise glucose, arabinose, xylose, galactose, rhamnose, and mannose in different molar ratios and glycosidic bond types. By varying the sources and extraction methods of A. roxburghii polysaccharides (ARPS), different structural characteristics and pharmacological activities can be elucidated. ARPS has been reported to exhibit antidiabetic, hepatoprotective, anti-inflammatory, antioxidant, antitumor, and immune regulation activities. This review summarizes the available literature on the extraction and purification methods, structural features, biological activities, and applications of ARPS. The shortcomings of the current research and potential focus in future studies are also highlighted. This review provides systematic and current information on ARPS to promote their further exploitation and application.

Ultrasonic Treatment Enhances the Antioxidant and Immune-Stimulatory Properties of the Polysaccharide from Sinopodophyllum hexandrum Fruit

We aimed to assess the potential of ultrasonic treatment on the processing of polysaccharides as functional foods or food additives. The polysaccharide from Sinopodophyllum hexandrum fruit (SHP, 52.46 kDa, 1.91 nm) was isolated and purified. SHP was treated with various levels of ultrasound (250 W and 500 W), resulting in the formation of two polysaccharides, SHP1 (29.37 kD, 1.40 nm) and SHP2 (36.91 kDa, 0.987 nm). Ultrasonic treatment was found to reduce the surface roughness and molecular weight of the polysaccharides, leading to thinning and fracturing. The effect of ultrasonic treatment on polysaccharide activity was evaluated in vitro and in vivo. In vivo experiments showed that ultrasonic treatment improved the organ index. Simultaneously, it enhanced the activity of superoxide dismutase, total antioxidant capacity, and decreased the content of malondialdehyde in the liver. In vitro experiments demonstrated that ultrasonic treatment also promoted proliferation, nitric oxide secretion, phagocytic efficiency, costimulatory factors (CD80+, CD86+) expression, and cytokine(IL-6, IL-1β) production of RAW264.7 macrophages.

Preparation of nano-selenium from chestnut polysaccharide and characterization of its antioxidant activity

Chestnut is widely cultivated and has high nutritional value due to its richness in polysaccharides. In order to improve the antioxidant activity of chestnut polysaccharide, chestnut polysaccharide (CP) was extracted by ultrasonic-assisted water extraction and alcohol precipitation and purified by cellulose DEAE-52 exchange and Sephadex G-100 chromatography in this study. CP isolates were characterized by I₂-KI reaction, three-strand helical structure analysis, infrared spectrum analysis, and nuclear magnetic resonance detection. The results showed that CP is a pyrylan sugar with triple helical structure and connected by α-glycosidic bonds, with sugar residues 1,4-α-D-Glcp, 1,6-α-D-Galp, 1,5-α-L-Araf, 1,4-α-L-Rhap, and 1,4-β-D-Glcp in the CP backbone. After purification, the branching structure, rod, and spherical structure were significantly increased, with reduced lamellar structure. The in vitro scavenging rates of CP at 10 mg·mL^-1 against DPPH, hydroxyl radicals, and ABTS were 88.95, 41.38, and 48.16%, respectively. The DPPH free radical scavenging rate of purified polysaccharide fraction CP-1a was slightly enhanced, and the other rates showed a small decrease. Selenized chestnut polysaccharide (CP-Se) was prepared using nano-selenium method. The selenization method was optimized and stable Se-CP was obtained. When the concentration was 5 mg·mL^-1, Se-CP had significantly higher scavenging abilities 89.81 ± 2.33, 58.50 ± 1.60, and 40.66 ± 1.91% for DPPH, hydroxyl radical, and ABTS radicals, respectively, than those of CP. The results of this study provide insight into the effects purification and selenization of chestnut polysaccharide on antioxidant activity, and also provide a theoretical basis for the development of chestnut polysaccharide for use in functional foods or health products.

Antioxidant properties of water-soluble polysaccharides prepared by co-culture fermentation of straw and shrimp shell

Herein, we present a method for producing water-soluble polysaccharides (WSPs) by co-culture fermentation of straw and shrimp shells. The chitin-degrading strain was isolated and genotypically identified as the non-pathogen Photobacterium sp. LYM-1 in this study. Photobacterium sp. LYM-1 and Aureobasidium pullulans 2012 could coexist without antagonism. WSPs concentrations were higher in co-culture fermentations of Photobacterium sp. LYM-1 and A. pullulans 2012 (PsL/AP-WSPs) compared to monocultures (PsL-WSPs and AP-WSPs). FTIR was used to examine the polysaccharide properties of three WSP fractions. The monosaccharide compositions of three WSPs fractions were primarily composed of mannose, ribose, glucosamine, glucose, galactose, and arabinose with varying molecular weights and molar ratios according to HPLC analysis. PsL/AP-WSPs showed better scavenging effects on DPPH, ABTS, and OH free radicals, demonstrating the application potential of PsL/AP-WSPs from straw and shrimp shells. The maximum yield obtained under optimum conditions (fermentation time of 6 days, temperature of 31°C, inoculum concentration of 10% (w/v), and inoculum composition of 2:1) was 5.88 ± 0.40 mg/mL, based on the PsL/AP-WSPs production optimization by orthogonal design. The results suggest that an environmentally friendly approach for WSPs production from agro-food wastes straw and shrimp shells was developed.

Ultrasonic-Cellulase Synergistic Extraction of Crude Polysaccharides from Moringa oleifera Leaves and Alleviation of Insulin Resistance in HepG2 Cells

Moringa oleifera leaves (MOL) are a new food resource, rich in functional factors. MOL polysaccharides are important active macromolecules within MOL. However, there are problems, such as low extraction rates and lack of evidence for functional activity. Therefore, in this experiment, single-factor experiments were carried out using MOL powder as the raw material, and the Plackett-Burman test was used to screen the significantly influential test factors. The extraction process of MOL polysaccharide was optimized by response surface methodology. The insulin resistance alleviating activity of MOLP polysaccharides was initially explored. The results showed that the extraction of Moringa oleifera leaves crude polysaccharides (MOLP) by ultrasonic assisted cellulase enzymatic digestion was (17.03 ± 1.03)%, and the obtained MOLP was a crude polysaccharide with an average molecular weight (Mw) of 279.48 kDa, consisting of fucose, rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid. MOLP had an IC50 value of 8.02 mg/mL for α-glucosidase and scavenging activity against free radicals such as ABTS, DPPH, hydroxyl radicals, and superoxide anion with an IC50 value of 0.21 mg/mL 0.31 mg/mL 0.97 mg/mL 0.49 mg/mL. At the same time, MOLP significantly enhanced the glucose consumption, glycogen synthesis, CAT, SOD, GSH-Px activity, and reduced the MDA and ROS content in high glucose-induced insulin-resistant HepG2 (IR-HepG2) cells. This experiment improved the extraction rate of MOLP and demonstrated that MOLP has antioxidant activity and α-glucosidase inhibitory activity, which can alleviate the insulin resistance of high glucose-induced HepG2 cells. It provides partial data support for the possible hypoglycemic effect of MOLP by alleviating oxidative stress, and also provides new ideas for the in-depth study of basic research and industrial application of MOLP.

Polysaccharides in Selenium-Enriched Tea: Extraction Performance under Innovative Technologies and Antioxidant Activities

Pulsed electric fields (PEF) and ultrasonic-assisted extraction (UE) were applied to improve the extraction performance of selenium-enriched tea polysaccharides (Se−TPSs) in mild conditions. Two combined extraction processes were investigated: (1) PEF strength at 10 kV/cm followed by conventional extraction (CE) at 50 °C for 60 min and (2) PEF+UE (PEF strength at 10 kV/cm followed by UE at 400 W for 60 min). The optimal extraction yields, and energy consumption rates were obtained at 36.86% and 41.53% and 78.78 kJ/mg and 133.91 kJ/mg, respectively. The Se−TPSs were analyzed and characterized by GPC, UV, and FT-IR, which evidenced the structural stability of the Se−TPSs during the extraction processes. It was found that PEF and UE could reduce the particle size diameter of the Se−TPS extract, as well as the proportion of uronic acid. Moreover, PEF could increase the selenium content in the Se−TPS extract by 160.14% due to a lower extraction temperature compared to conventional extraction. The antioxidant activities of the Se−TPSs in vitro were investigated using OH, O2−, and ABTS+ scavenging experiments, as well as a total antioxidant ability evaluation. It was found that the antioxidant activity of the Se−TPSs obtained using PEF₂+CE₂ was relatively high due to the potential synergistic effect between the selenium and polysaccharides. Based on these results, we speculate that PEF₂+CE₂ was the best extraction process for the Se−TPSs. Furthermore, this research indicates the application of selenium-enriched tea for functional food production.

Polysaccharide from Hemerocallis citrina Borani by subcritical water: Bioactivity, purification, characterization, and anti-diabetic effects in T2DM rats

Hemerocallis citrina Borani (daylily) has various health benefits. However, the structural characterization and hypoglycemic effects of its polysaccharide remain unclear. Here, we first report for the first time, the effects of subcritical water extraction temperature on bioactivity of Hemerocallis citrina Borani polysaccharide (HCBP). HCBP extracted at 160 °C had better scavenging ability of free-radical and pancreatic lipase inhibition. This study aimed to investigate the structural characterization and anti-diabetic effects of aforementioned HCBP. HCBP was separated into three fractions using a DEAE-Sepharose Fast Flow. HCBP-1 was the major component with lower molecular weight, HCBP-2 was the least abundant component, HCBP-3 was the component with higher uronic acid and molecular weight. HCBP treatment significantly decreased the concentrations of fasting blood glucose, insulin, total cholesterol, triglyceride, and low density lipoprotein, as well as improved glucose intolerance and insulin resistance in type 2 diabetes mellitus (T2DM) rats. HCBP also protected the kidneys and pancreatic organs by histopathology and immunohistochemical analyses in T2DM rats. In addition, HCBP significantly increased the antioxidant enzymes activities and decreased the level of malonaldehyde to alleviated the oxidative stress injury. The results indicate HCBP extracted by subcritical water is promising functional food ingredients and could be used in T2DM treatment.