Distinguishing α/ß-linkages and linkage positions of disaccharides in galactooligosaccharides through mass fragmentation and liquid retention behaviour.

Galactooligosaccharides (GOS) are important prebiotics with function closely related to their structure. However, a comprehensive overview of the structure-function relationship is still limited due to the challenge in characterizing multiple isomers in GOS. This study presents a strategy of combining both hydrophilic interaction liquid chromatography (HILIC) retention time and tandem mass spectrometry (MS/MS) fragmentation pattern to distinguish α/ß-linkages and linkage positions of disaccharide isomers in GOS through HILIC-MS/MS analysis. The results indicated that the ratio of m/z 203.0524 to m/z 365.1054 could distinguish α/ß-linkages, while the ratios of m/z 347.0947 to m/z 365.1054, m/z 245.0642 to m/z 365.1054 and HILIC retention time could distinguish (1 â†’ 2), (1 â†’ 3), (1 â†’ 4) and (1 â†’ 6) linkages. The above rules enabled effective characterization of disaccharides in GOS-containing food samples, including milk powder, rice flour, drink, yogurt. This method can be used in the quality control of GOS and future research on the structure-specific health effects of GOS.

In vitro simulated digestion and fermentation characteristics of pectic polysaccharides from fresh passion fruit (Passiflora edulis f. flavicarpa L.) peel.

In this study, two pectic polysaccharides (PFP-T and PFP-UM) were extracted from fresh passion fruit peels using three-phase partitioning (TPP) and sequential ultrasound-microwave-assisted TPP methods, respectively, and their effects on the in vitro gastrointestinal digestion and fecal fermentation characteristics were examined. The results indicate that gastrointestinal digestion has a minimal effect on the physicochemical and structural characteristics of PFP-T and PFP-UM. However, during in vitro fecal fermentation, both undigested PFP-T and PFP-UM are significantly degraded and utilized by intestinal microorganisms, showing increased the total relative abundance of Firmicutes and Bacteroidota in the intestinal flora. Notably, compared with PFP-UM, PFP-T better promoted the reproduction of beneficial bacteria such as Prevotella, Megasphaera and Dialister, while suppressed the growth of harmful genera including Escherichia-Shigella, producing higher content of short-chain fatty acids. Therefore, our findings suggest that PFP-T derived from passion fruit peel has potential as a dietary supplement for promoting intestinal health.

How food matrices modulate folate bioaccessibility: A comprehensive overview of recent advances and challenges.

The incomplete absorption of dietary folate makes it crucial to understand how food matrices affect folate bioaccessibility. Bioavailability encompasses bioaccessibility, which depicts the proportion that is liberated from the food matrix during digestion and becomes available for absorption. Bioavailability studies are expensive and difficult to control, whereas bioaccessibility studies utilize in vitro digestion models to parameterize the complex digestion, allowing the evaluation of the effect of food matrices on bioaccessibility. This review covers the folate contents in various food matrices, the methods used to determine and the factors affecting folate bioaccessibility, and the advances and challenges in understanding how food matrices affect folate bioaccessibility. The methods for determining bioaccessibility have been improved in the last decade. Current research shows that food matrices modulate folate bioaccessibility by affecting the liberation and stability of folate during digestion but do not provide enough information about folate and food component interactions at the molecular level. In addition, information on folate interconversion and degradation during digestion is scant, hindering our understanding of the impact of food matrices on folate stability. Moreover, the role of conjugase inhibitors should not be neglected when evaluating the nutritional value of food folates. Due to the complexity of food digestion, holistic methods should be applied to investigate bioaccessibility. By synthesizing the current state of knowledge on this topic, this review highlights the lack of in-depth understanding of the mechanisms of how food matrices modulate folate bioaccessibility and provides insights into potential strategies for accurate evaluation of the nutritional value of dietary folate.

Konjac Glucomannan Counteracted the Side Effects of Excessive Exercise on Gut Microbiome, Endurance, and Strength in an Overtraining Mice Model.

Excessive exercise without adequate rest can lead to overtraining syndrome, which manifests a series of side effects, including fatigue, gut dysbiosis, and decremental sports performance. Konjac glucomannan (KGM) is a plant polysaccharide with numerous health-improving effects, but few studies reported its effects on the gut microbiome, endurance, and strength in an overtraining model. This study assessed the effect of KGM on gut microbiome, endurance, and strength in mice with excessive exercise. Three doses of KGM (1.25, 2.50, and 5.00 mg/mL) were administrated in drinking water to mice during 42 days of a treadmill overtraining program. The results showed that excessive exercise induced a significant microbial shift compared with the control group, while a high dose (5.00 mg/mL) of KGM maintained the microbial composition. The proportion of Sutterella in feces was significantly increased in the excessive exercise group, while the moderate dose (2.50 mg/mL) of KGM dramatically increased the relative abundance of Lactobacillus and SCFA production in feces. Additionally, the moderate dose and high dose of KGM counteracted the negative effects of excessive exercise on strength or/and endurance (43.14% and 39.94% increase through a moderate dose of KGM, Bonferroni corrected p < 0.05, compared with the excessive exercise group). Therefore, it suggests that KGM could prevent overtraining and improve sports performance in animal models.

Polysaccharide extracted from cultivated Sanghuangporous vaninii spores using three-phase partitioning with enzyme/ultrasound pretreatment: Physicochemical characteristics and its biological activity in vitro.

Sanghuangporous vaninii, as a valuable dietary supplement and medicinal ingredient, contains abundant bioactive polysaccharides that have health-promoting effects. In the present study, four polysaccharides (SVSPs-C, SVSPs-E, SVSPs-U, and SVSPs-E/U) were extracted for the first time from S. vaninii spores by three-phase partitioning (TPP), enzyme pretreatment before TPP (E-TPP), ultrasonic pretreatment before TPP (U-TPP), and enzyme pretreatment followed by ultrasonic before TPP (E/U-TPP) methods, respectively. Their physicochemical characteristics and in vitro pharmacological functions were determined and compared. Results showed that four TPP-based extraction methods had remarkable impacts on the extraction yield, chemical properties, monosaccharide compositions, and molecular weights (Mw) of SVSPs. Specifically, SVSPs-E/U obtained by E/U-TPP showed the highest extraction yield (25.40 %), carbohydrate content (88.50 %), and the lowest protein content (0.86 %). The four SVSPs had high-Mw (183.8-329.1 kDa) and low-Mw (23.0-156.4 kDa) fractions and mainly consisted of galactose, glucose, and mannose with different contents. In vitro bioactivities assays indicated that SVSPs-E/U possessed stronger antioxidant, hypoglycemic, hypouricemic, immunostimulatory, and antitumor activities than those of SVSPs-C, SVSPs-E, and SVSPs-U. Therefore, our results provide an efficient and promising extraction technique for bioactive polysaccharides from S. vaninii spores, as well as SVSPs had the potential to be applied in functional food, pharmaceutical, and cosmetics fields.

Effects of direct addition of curdlan on the gelling characteristics of thermally induced soy protein isolate gels.

In this study, the effects of the direct addition of curdlan on the physicochemical, structural, and functional properties of heat-induced soy protein isolate (SPI) gels were evaluated. Results demonstrated that the direct incorporation of curdlan enhanced the gel-forming performance, water-holding capacity, and gel strength of heat-induced SPI gels. The presence of curdlan reduced the free water molecules and α-helix content in the SPI structure and contributed to the construction of stable SPI gels with uniform and compact network structures, as visually proven by microstructure observations. Moreover, compared with the SPI gel alone, the curdlan-SPI composite gels presented a more pronounced viscoelastic property and thermal stability mainly due to the intermolecular hydrogen bonding interaction between curdlan and the SPI molecules. Our findings suggest that the direct incorporation of curdlan can effectively ameliorate the gelling characteristics of heat-induced SPI gels, indicating its potential application as a promising gel improver in the food industry.

The anti-hyperlipidemic effect and underlying mechanisms of barley (Hordeum vulgare L.) grass polysaccharides in mice induced by a high-fat diet.

Hyperlipidemia is a pathological disorder of lipid metabolism that can cause fatty liver, atherosclerosis, acute myocardial infarction, and other diseases, seriously endangering people's health. Polysaccharides have been shown to have lipid-lowering potential. In the current study, the anti-hyperlipidemia effect and potential mechanisms of a polysaccharide (BGP-Z31) obtained from barley grass harvested at the stem elongation stage in high-fat diet (HFD)-treated mice were investigated. Results showed that supplementation with BGP-Z31 (200 and 400 mg kg-1) not only suppressed obesity, organ enlargement, and fat accumulation caused by HFD, but also regulated dyslipidemia, relieved liver function injury, and ameliorated the oxidative stress level. Meanwhile, BGP-Z31 increased the concentrations of acetic acid, propionic acid, butyric acid, and isovaleric acid in HFD-induced mice. Gut microbiota analysis demonstrated that BGP-Z31 had no obvious effect on the gut microbiota diversity in mice treated with HFD, but it positively remodeled the intestinal flora structure by elevating the relative abundances of Bacteroides, Muribaculaceae, and Lachnospiraceae and lowering the Firmicutes/Bacteroides value and the relative abundance of Desulfovibrionaceae. Therefore, our data suggested that BGP-Z31 can be used as a promising nutritional supplement for dietary intervention in hyperlipidemia.

Automatic segmentation of cotton roots in high-resolution minirhizotron images based on improved OCRNet.

Root phenotypic parameters are the important basis for studying the growth state of plants, and root researchers obtain root phenotypic parameters mainly by analyzing root images. With the development of image processing technology, automatic analysis of root phenotypic parameters has become possible. And the automatic segmentation of roots in images is the basis for the automatic analysis of root phenotypic parameters. We collected high-resolution images of cotton roots in a real soil environment using minirhizotrons. The background noise of the minirhizotron images is extremely complex and affects the accuracy of the automatic segmentation of the roots. In order to reduce the influence of the background noise, we improved OCRNet by adding a Global Attention Mechanism (GAM) module to OCRNet to enhance the focus of the model on the root targets. The improved OCRNet model in this paper achieved automatic segmentation of roots in the soil and performed well in the root segmentation of the high-resolution minirhizotron images, achieving an accuracy of 0.9866, a recall of 0.9419, a precision of 0.8887, an F1 score of 0.9146 and an Intersection over Union (IoU) of 0.8426. The method provided a new approach to automatic and accurate root segmentation of high-resolution minirhizotron images.

Modified RNN for Solving Comprehensive Sylvester Equation With TDOA Application.

The augmented Sylvester equation, as a comprehensive equation, is of great significance and its special cases (e.g., Lyapunov equation, Sylvester equation, Stein equation) are frequently encountered in various fields. It is worth pointing out that the current research on simultaneously eliminating the lagging error and handling noises in the nonstationary complex-valued field is rather rare. Therefore, this article focuses on solving a nonstationary complex-valued augmented Sylvester equation (NCASE) in real time and proposes two modified recurrent neural network (RNN) models. The first proposed modified RNN model possesses gradient search and velocity compensation, termed as RNN-GV model. The superiority of the proposed RNN-GV model to traditional algorithms including the complex-valued gradient-based RNN (GRNN) model lies in completely eliminating the lagging error when employed in the nonstationary problem. The second model named complex-valued integration enhanced RNN-GV with the nonlinear acceleration (IERNN-GVN) model is proposed to adapt to a noisy environment and accelerate the convergence process. Besides, the convergence and robustness of these two proposed models are proved via theoretical analysis. Simulative results on an illustrative example and an application to the moving source localization coincide with the theoretical analysis and illustrate the excellent performance of the proposed models.

Cotton leaf segmentation with composite backbone architecture combining convolution and attention.

Plant leaf segmentation, especially leaf edge accurate recognition, is the data support for automatically measuring plant phenotypic parameters. However, adjusting the backbone in the current cutting-edge segmentation model for cotton leaf segmentation applications requires various trial and error costs (e.g., expert experience and computing costs). Thus, a simple and effective semantic segmentation architecture (our model) based on the composite backbone was proposed, considering the computational requirements of the mainstream Transformer backbone integrating attention mechanism. The composite backbone was composed of CoAtNet and Xception. CoAtNet integrated the attention mechanism of the Transformers into the convolution operation. The experimental results showed that our model outperformed the benchmark segmentation models PSPNet, DANet, CPNet, and DeepLab v3+ on the cotton leaf dataset, especially on the leaf edge segmentation (MIoU: 0.940, BIoU: 0.608). The composite backbone of our model integrated the convolution of the convolutional neural networks and the attention of the Transformers, which alleviated the computing power requirements of the Transformers under excellent performance. Our model reduces the trial and error cost of adjusting the segmentation model architecture for specific agricultural applications and provides a potential scheme for high-throughput phenotypic feature detection of plants.

Recent advances in research on Allium plants: functional ingredients, physiological activities, and applications in agricultural and food sciences.

Fruits and vegetables (FVs) have long been a major source of nutrients and dietary phytochemicals with outstanding physiological properties that are essential for protecting humans from chronic diseases. Moreover, the growing demand of consumers for nutritious and healthy foods is greatly promoting the increased intake of FVs. Allium (Alliaceae) is a perennial bulb plant genus of the Liliaceae family. They are customarily utilized as vegetable, medicinal, and ornamental plants and have an important role in agriculture, aquaculture, and the pharmaceutical industry. Allium plants produce abundant secondary metabolites, such as organosulfur compounds, flavonoids, phenols, saponins, alkaloids, and polysaccharides. Accordingly, Allium plants possess a variety of nutritional, biological, and health-promoting properties, including antimicrobial, antioxidant, antitumor, immunoregulatory, antidiabetic, and anti-inflammatory effects. This review aims to highlight the advances in the research on the bioactive components, physiological activities and clinical trials, toxicological assessment for safety, and applications of different Allium plants. It also aims to cover the direction of future research on the Allium genus. This review is expected to provide theoretical reference for the comprehensive development and utilization of Allium plants in the fields of functional foods, medicine, and cosmetics.

Heat-induced amorphous aggregates assembly of soy protein modulate in vitro digestibility of potato starch.

This research focused on the characteristics of amorphous aggregates derived from soy protein (SPAA), and their effects on the structural, physicochemical, and digestive properties of potato starch (PS). The SPAA induced by different heating temperatures at pH 7.0 formed an inhomogeneous spherical structure. The presence of SPAA could improve the degree of short-range order of starch, increase thermal stability, reduce pasting viscosity and breakdown, and setback viscosity values of PS. For the PS complexed with SPAAs under simulated cooking conditions, the fraction of digested starch at 300 min (C300) decreased by 6-14 %, and rapid digestible starch content (RDS) decreased by 18-25 %, while the slowly digestible starch (SDS) and resistant starch (RS) increased by 0.4-3 % and 15-23 %, respectively. The SPAA at higher temperature treatment (SPAA130) reduced digestive rate coefficient (k) values more significantly than SPAA at a lower temperature (SPAA70, SPAA90, SPAA110). And the SPAA had no inhibitory effect on α-amylase. The results of this study would significantly contribute to expanding the theoretical information about protein regulation in starch digestion and promoting the development of healthy foods with digestion-resistant properties.

Structural characteristics and ameliorative effect of a polysaccharide from Corbicula fluminea industrial distillate against acute liver injury induced by CCl4 in mice.

Corbicula fluminea distillate as an important industrial by-product of C. fluminea during steaming process is rich in amino acids, proteins and polysaccharides, showing potential hepatoprotective effect. In this study, a polysaccharide (CFDP) was obtained from C. fluminea distillate by three-phase partitioning combined with (NH4)2SO4 precipitation at a saturation of 60 %. The structural characteristics, antioxidant activity in vitro, and hepatoprotection against mice CCl4-induced acute liver damage of CFDP were studied. Results demonstrated that CFDP was a water-soluble homogenous polysaccharide predominantly comprising glucose (>98 %), with a weight-average molecular weight of 1.4 × 107 Da, and exhibiting potent antioxidant benefits in vitro. CFDP had a backbone of (1 â†’ 4)-α-d-glucopyranosyl (Glcp) and a small amount of (1 â†’ 4, 6)-α-D-Glcp. The branch formed at C-6 comprised by (1→)-α-D-Glcp and (1→)-α-D-N-acetylglucosamine. CFDP possessed excellent hepatoprotective activity against acute liver damage caused by CCl4 in mice, mainly by ameliorating weight reduction and organ injures, alleviating hepatic function and serum lipid metabolism, suppressing oxidative stress and inflammatory responses, as directly verified by histopathological examination. Moreover, CFDP improved gut microbiota by up-regulating the relative abundance of total bacteria and probiotics such as Firmicutes, Bacteroidete, Rumminococcaceae, Lactobacillaceae, accompanied by promoting short chain fatty acid production. Therefore, our findings indicated that CFDP can be developed as a healthy food supplement for the prevention of chemical livery injury.

A pectic polysaccharide from fresh okra (Abelmoschus esculentus L.) beneficially ameliorates CCl4-induced acute liver injury in mice by antioxidation, inhibition of inflammation and modulation of gut microbiota.

Okra [Abelmoschus esculentus (Linn.) Moench], as a well-known medicinal and food plant, has important physiological activities and health benefits, and polysaccharide is its main bioactive component. In this study, a pectic polysaccharide (OPS-50) prepared from fresh okra pods by three-phase partitioning and gradient (NH4)2SO4 precipitation at a saturation of 50% was employed in carbon tetrachloride (CCl4)-caused acute liver damage in mice to evaluate the hepatoprotective potential. Results indicated that OPS-50 was mainly composed of a limited linear homogalacturonan backbone and abundant rhamnogalacturonan-I domains as side chains. OPS-50 exerted positively protective effects on acute liver damage induced by CCl4 in mice through relieving weight reduction and organ damage, ameliorating liver function and dyslipidemia, alleviating oxidative stress, suppressing pro-inflammatory cytokines, modulating gut microbiota, and promoting short-chain fatty acid secretion. Moreover, liver histopathology demonstrated the protective benefit of OPS-50 on CCl4-caused acute liver damage in mice. Therefore, our data suggested that the pectic OPS-50, as a dietary supplement, have great potential in preventing and treating chemical liver damages.

Recent advances in the bioactive polysaccharides and other key components from Phellinus spp. and their pharmacological effects: A review.

Phellinus spp. is one of the largest genera of Hymenochaetaceae with approximately 220 species, such as P. vaninii, P. buamii, P. linteus, and P. igniarius, these species are considered as precious food supplements and medicinal ingredients in China, Korea, Japan, and other Asian countries for over 2000 years. Phellinus spp. contains abundant bioactive polysaccharides and other key components (e.g., phenolics, terpenes, steroids, etc.). Pharmacological investigations have confirmed that bioactive polysaccharides and other important secondary metabolites from Phellinus spp. possess multiple health-promoting benefits, including antitumor, immunomodulatory, anti-inflammatory, antidiabetic, antioxidant, and antimicrobial effects. However, comprehensive evaluations on the preparation and structural characteristics, bioactivities, and toxicology of these functional components (e.g., polysaccharides, phenolics, terpenes, steroids) from various Phellinus spp. species are very limited, which may restrict the practical application of Phellinus spp. This review summarizes the physicochemical characteristics, pharmacological activities, and possible mechanisms of bioactive components from Phellinus spp. according to published studies from 2017 to 2022. It also surveyed the toxicological assessment for safety and applications of different Phellinus spp. species. This review aims to provide useful references and promising directions for the comprehensive development and utilization of Phellinus spp. in functional foods, pharmaceuticals, and cosmetics.

In vitro simulated digestion affecting physicochemical characteristics and bioactivities of polysaccharides from barley (Hordeum vulgare L.) grasses at different growth stages.

In this study, three polysaccharides (BGPs: BGPs-Z21, BGPs-Z23, and BGPs-Z31) were successively extracted from barley (Hordeum vulgare L.) grasses (BG) at different growth stages, including seedling (Z21), tillering (Z23), and stem elongation (Z31). The effects of in vitro simulated saliva-gastrointestinal digestion on the physicochemical characteristics and biological activities of BGPs were investigated and compared. Results showed that the simulated saliva-gastrointestinal digestion had considerable influences on reducing sugar content, chemical components, monosaccharide constituents, and molecular weights of BGPs but hardly affected their preliminarily structural characteristics. Moreover, the antioxidant activities of BGPs were weakened after the simulated saliva-gastrointestinal digestion, but their bile acid-binding capacities were remarkably enhanced. The digested BGPs-Z31 by gastric juice possessed better antioxidant benefit, and bile acid-binding capacity (80.33 %) than other digested products. Overall, these results indicated that BGPs obtained from BG are valuable for functional foods as promising bioactive ingredients.

Polysaccharide-based nanoparticles fabricated from oppositely charged curdlan derivatives for curcumin encapsulation.

In this study, carboxylic curdlan (Cur-48) and negatively charged ferulic acid (FA)-grafted carboxylic curdlan (Cur-48-g-FA) were separately used to fabricate polyelectrolyte nanoparticles (PNPs: PNPs-CQ and PNPs-CFQ) with positively charged quaternized curdlan (Qcurd) for curcumin delivery. Results showed that curcumin-loaded PNPs-CQ and PNPs-CFQ had particle sizes of 338.1 and 301.3 nm, zeta potentials of -19.07 and -24.10 mV, and encapsulation efficiencies of 76.32% and 83.54%, respectively. Curcumin was properly encapsulated inside the two PNPs through electrostatic interactions and hydrogen bonds. Compared with free curcumin, entrapped curcumin in the two PNPs exhibited better redispersion performance, thermo- and photostability, and sustained release property. Furthermore, FA molecules surrounding the surface of PNPs-CFQ were conductive to the entrapped curcumin's particulate characteristics, stability, release behavior, and antioxidant potentials. Therefore, our findings indicated that PNPs formulated via Cur-48-g-FA and Qcurd can provide a novel delivery platform for encapsulation of hydrophobic nutrients, including curcumin, in functional foods.

Comparison of physicochemical characteristics and biological activities of polysaccharides from barley (Hordeum vulgare L.) grass at different growth stages.

Barley grass polysaccharides (BGPs) are some of the major bioactive constituents of barley (Hordeum vulgare L.) grass (BG). They exhibit favorable biological activities and health benefits. In this study, seven BGPs were extracted from BG, which was harvested at three different growth stages (e.g., seedling, tillering, and stem elongation), by alkaline-extraction method. Their physicochemical properties, structural characteristics, and biological activities were investigated and compared. Results demonstrated that the extraction yields, chemical compositions, monosaccharide constituents, and molecular weights of the seven BGPs obtained at different growth stages varied obviously. These BGPs had similar preliminary structural characteristics but different microstructures and thermal properties. Furthermore, the BGPs (BGP-Z12 and BGP-Z21) obtained at the seedling stage possessed stronger in vitro antioxidant potentials, cholic acid binding activity, and immunological activity than other BGPs. Therefore, these results indicated that that the seedling stage of BG was the preferable harvest time for preparing highly bioactive BGPs.

Modulatory effects of polysaccharides from plants, marine algae and edible mushrooms on gut microbiota and related health benefits: A review.

Naturally occurring carbohydrate polymers containing non-starch polysaccharides (NPs) are a class of biomacromolecules isolated from plants, marine algae, and edible mushrooms, and their biological activities has shown potential uses in the prevention and treatment of human diseases. Importantly, NPs serve as prebiotics to provide health benefits to the host through stimulating the proliferation of beneficial gut microbiota (GM) and enhancing the production of short-chain fatty acids (SCFAs). The composition and diversity of GM play a critical role in regulating host health and have been extensively studied in recent years. In this review, the extraction, isolation, purification, and structural characterization of NPs derived from plants, marine algae, and edible mushrooms are outlined. Importantly, the degradation and metabolism of these NPs in the intestinal tract, the effects of NPs on the microbial community and SCFAs generation, and the beneficial effects of NPs on host health by modulating GM are systematically highlighted. Overall, we hope that this review can provide some theoretical references and a new perspective for applications of NPs as prebiotics in functional food and drug development.