In vitro binding capacities, physicochemical properties and structural characteristics of polysaccharides fractionated from Passiflora edulis peel

Hydrolyzable tannins and pectin are glycolipid lowering ingredients in Phyllanthus emblica Linn.: Valid interaction with gut action targets

Phyllanthus emblica L., a distinctive fruit, is rich in polyphenols and polysaccharide. However, there is a lack of knowledge regarding the role of these compounds as glycolipid lowering ingredients. In this study, the glycolipid lowering ingredients and their effects have been determined by gradually comparing varieties, parts, and components, splitting components, and calculating combined index via their interactions with digestion enzymes, bile acids, cholesterol micelles and probiotics. Results indicated that the glycolipid lowering ingredients were polyphenols and polysaccharide, which located in the pulp, and not influenced by the variety. Pectin with multiple structural domains, and hydrolyzable tannins, i.e. gallic acid, ellagic acid and their derivatives interacted with multiple gut action targets could regulate glycolipid digestion, absorption and metabolism. Polysaccharide and polyphenols demonstrated a synergistic effect in lowering glycolipid by interacting with gut action targets. These findings highlight the potential for further investigation and utilization of glycolipid lowering ingredients in fruits.

A novel polysaccharide from blueberry leaves: Extraction, structural characterization, hypolipidemic and hypoglycaemic potentials

In this study, the structural characterization, physicochemical properties, antioxidant, hypolipidemic, and hypoglycemic potentials of polysaccharide components (BLP-1, BLP-2, and BLP-3) purified from blueberry leaf polysaccharides (BLP) were investigated. Ion chromatography results showed that BLP-1, BLP-2, and BLP-3 contained rhamnose, arabinose, galactose, glucose, and glucuronic acid. In contrast to BLP-1, BLP-2 and BLP-3 included galacturonic acid. The methylation analysis results indicated that the backbones of BLP-1, BLP-2, and BLP-3 were mainly composed of glycosidic linkages of arabinose, galactose, and glucose, which was consistent with the results of the previously determined monosaccharide composition. The in-vitro antioxidant results showed that BLP-1, BLP-2, and BLP-3 possessed antioxidant activity with the highest scavenging of -OH radicals. Furthermore, BLP-1, BLP-2, and BLP-3 showed high bile acid-binding activity and α-amylase inhibitory activity, suggesting that they have the potentials of hypolipidemic and hypoglycemic. This study provides a reference for the utilization of blueberry leaf resources.

Utilization of electron beam irradiation pretreatment for the extraction of pectic polysaccharides from Diaphragma juglandis fructus: Structural, physicochemical, and functional properties

The effects of electron beam irradiation (EBI) pretreatment on the alkaline extraction of pectic polysaccharides from Diaphragma juglandis fructus (DJF) are highly dependent on the irradiation dosage. Comprehensive characterizations encompassing physicochemical, structural, and functional properties were conducted on crude pectic polysaccharide extract from DJF subjected to various EBI doses. EBI pretreatment significantly increased the yields of crude pectic polysaccharides extract (increasing by 41.89 %), also facilitating the extraction of uronic acid, RG-I structure, and protein content, despite causing a decrease in total sugar content. EBI pretreatment induced the degradation of pectin, resulting in decreased molecular weight, particle size, crystallinity, viscosity, thermal stability, and water holding capacity, while enhancing solubility and oil holding capacity. Variations in physicochemical and structural properties induced by different EBI doses influenced the functional activities of DJF pectic polysaccharides. Low-dose EBI (at 5 kGy) pretreatment markedly improved the emulsifying activity/stability (increasing by 20.82/74.10 %) and ABTS/DPPH radical scavenging activity (increasing by 27.91/12.40 %), whereas high-dose EBI pretreatment (50 kGy) greatly enhanced foaming capacity/stability (increasing by 259.99/175.56 %). These findings provide a novel regulatory strategy for the functional activity of pectic polysaccharides.

The Anti-Diabetic Effect of Non-Starch Polysaccharides Extracted from Wheat Beer on Diet/STZ-Induced Diabetic Mice

Diabetes mellitus (DM), a major cause of mortality, is characterized by insulin resistance and β-cell dysfunction. The increasing prevalence of DM is linked to lifestyle changes and there is a need for alternative approaches to conventional oral hypoglycemic agents. Polysaccharides, particularly non-starch polysaccharides (NSPs), have been identified as promising hypoglycemic agents. Cereals, especially wheat, are key sources of dietary polysaccharides, with NSPs derived from wheat beer attracting significant interest. This study aimed to investigate the hypoglycemic and hypolipidemic effects of NSPs extracted from wheat beer in STZ-induced diabetic C57BL/6J male mice. The results showed that NSPs extract positively influenced blood glucose regulation, lipid profiles, and liver and kidney functions, by attenuating liver AST and kidney CRE levels in a dose-dependent manner. The NSPs demonstrated anti-oxidative and anti-inflammatory properties, potentially providing significant benefits in managing diabetes and its complications. Moreover, the study revealed the histoprotective effects of NSPs on the liver and pancreas, reducing lipid deposition, necrosis, and inflammation. These findings highlight the multifaceted advantages of NSPs and suggest their potential as effective agents in diabetes management. This study supports the need for further research into the therapeutic potential of NSPs and their application in developing innovative treatments for diabetes and its associated complications.

Purification of Phenolic Compounds from Camellia polyodonta Flower: Composition Analysis, Antioxidant Property, and Hypolipidemic Activity In Vitro and In Vivo

Camellia polyodonta flowers are rich sources of phenolics and less attention has been paid to their potential biological activity. This study aims to explore the crude extracts and resulting purified fractions (CPFP-I, II, III, and IV) through compositional analysis and antioxidant and hypolipidemic activities in vitro and in vivo. Among four fractions, CPFP-II contained the highest total phenolic content and flavonoid content, while CPFP-III exhibited the greatest total proanthocyanidin content. Among the 14 phenolic compounds, CPFP-II displayed the highest content of procyanidin B2, B4, and C1, whereas CPFP-III contained the highest amount of 1,2,3,6-tetragalloylglucose. The DPPH, ABTS, and FRAP assessments demonstrated a consistent trend: CPFP-II > CPFP-III > CPFP-I > CPFP-IV. In vivo experiments showed that that all four fractions significantly reduced lipid levels in hyperlipidemic C. elegans (p < 0.05), with CPFP-II exhibiting the most potent effect. Furthermore, CPFP-II effectively bound to bile acids and inhibited the enzymatic activity of pancreatic lipase in vitro. Consequently, CPFP-II should be prioritized as a promising fraction for further exploration and should provide substantial support for the feasibility of the C. polyodonta flower as a natural alternative.

Enhancement of γ-Aminobutyric Acid and the Characteristics of Nutrition and Function in White Quinoa through Ultrasound Stress at the Pre-Germination Stage

The global production of quinoa has been increasing in recent years. In plant-based foods, ultrasound stress has received increasing attention, owing to its ability to enhance the production of primary and secondary metabolites. We studied the effects of ultrasonic stress at the pre-germination stage on the γ-aminobutyric acid (GABA) accumulation and characteristics of nutrition and function in quinoa. The results showed that ultrasonic conditions of 100 W for 4 min promoted an increase in GABA content by 9.15-fold, to 162.47 ± 6.69 mg/100 g·DW, compared to that of untreated quinoa, through promoting a 10.2% and 71.9% increase in the water absorption and glutamate decarboxylase activity of quinoa, respectively. Meanwhile, compared to untreated quinoa, ultrasonic stress at the pre-germination stage enhanced the total phenolic, total flavonoid, and total saponin contents of quinoa by 10.2%, 33.6%, and 90.7%, to 3.29 mg GA/g·DW, 104.0 mg RE/100 g·DW, and 7.13 mg/g, respectively, without decreasing its basic nutritional quality. Ultrasonic stress caused fissures on the surface of quinoa starch particles. Additionally, germination under ultrasonic stress increased the n3 polyunsaturated fatty acids by 14.4%. Furthermore, ultrasonic stress at the pre-germination stage promoted the scavenging of 2,2-diphenyl1-picrylhydrazyl radicals and inhibitions of α-amylase, α-glucosidase, and pancreatic lipase by 14.4%, 14.9%, 24.6%, and 20.0% in vitro, compared to untreated quinoa. The results indicated that the quinoa sprouted via ultrasonic stress could represent a promising method through which to develop nutritionally balanced whole grains rich in GABA, with hypoglycemic and hypolipidemic activities, which could provide theoretical support for the development of functional whole-grain foods based on quinoa.

Structural Characterization and In Vitro Antioxidant, Hypoglycemic and Hypolipemic Activities of a Natural Polysaccharide from Liupao Tea

This study extracted and purified a natural polysaccharide (TPS-5) that has a molecular weight of 48.289 kDa from Liupao tea, a typical dark tea with many benefits to human health. TPS-5 was characterized as a pectin-type acidic polysaccharide. It has a backbone composed of → 2,4)- α- L-Rhap-(1) → 4)- α- D-GalAp-(1) →, with a branch composed of → 5)- α- L-Ara-(1 → 5,3)- α- L-Ara-(1 → 3)- β- D-Gal-(1 → 3,6)- β- D-Galp-(1) →. The in vitro biological activity evaluation illustrated that TPS-5 has free radical scavenging, ferric-ion-reducing, digestive enzyme inhibitory, and bile-salt-binding abilities. These results suggest that TPS-5 from Liupao tea has potential applications in functional foods or medicinal products.

Structural Characteristics, Rheological Properties, and Antioxidant and Anti-Glycosylation Activities of Pectin Polysaccharides from Arabica Coffee Husks

As primary coffee by-products, Arabica coffee husks are largely discarded during coffee-drying, posing a serious environmental threat. However, coffee husks could be used as potential material for extracting pectin polysaccharides, with high bioactivities and excellent processing properties. Thus, the present study aimed to extract the pectin polysaccharide from Arabica coffee husk(s) (CHP). The CHP yield was calculated after vacuum freeze-drying, and its average molecular weight (Mw) was detected by gel permeation chromatography (GPC). The structural characteristics of CHP were determined by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), proton nuclear magnetic resonance (¹H NMR), and scanning electron microscopy (SEM). Additionally, the rheological and antioxidant properties of CHP and the inhibition capacities of advanced glycation end products (AGEs) with different concentrations were evaluated. The interaction mechanisms between galacturonic acid (GalA) and the AGE receptor were analyzed using molecular docking. The results demonstrated that the CHP yield was 19.13 ± 0.85%, and its Mw was 1.04 × 10⁶ Da. The results of the structural characteristics results revealed that CHP was an amorphous and low-methoxyl pectic polysaccharide linked with an α-(1→6) glycosidic bond, and mainly composed of rhamnose (Rha, 2.55%), galacturonic acid (GalA, 45.01%), β-N-acetyl glucosamine (GlcNAc, 5.17%), glucose (Glc, 32.29%), galactose (Gal, 6.80%), xylose (Xyl, 0.76%), and arabinose (Ara, 7.42%). The surface microstructure of CHP was rough with cracks, and its aqueous belonged to non-Newtonian fluid with a higher elastic modulus (G'). Furthermore, the results of the antioxidant properties indicated that CHP possessed vigorous antioxidant activities in a dose manner, and the inhibition capacities of AGEs reached their highest of 66.0 ± 0.35% at 1.5 mg/mL of CHP. The molecular docking prediction demonstrated that GalA had a good affinity toward AGE receptors by -6.20 kcal/mol of binding energy. Overall, the study results provide a theoretical basis for broadening the application of CHP in the food industry.