Correlations of Molecular Weights of β-Glucans from Qingke (Tibetan Hulless Barley) to Their Multiple Bioactivities

Structural and functional characteristics of pectins from three cultivars of apple (Malus pumila Mill.) pomaces

This study aimed to investigate the chemical composition, structural properties, and biological properties of pectin polysaccharides (AP-FS, AP-QG, and AP-HG) isolated from different varieties of apple pomace. Based on the methylation and nuclear magnetic resonance analyses, the structure of AP-FS was determined to be composed of an α-1,4-linked homogalacturonan backbone that exhibited high levels of O-6 methylation. All pectins exhibit potent inhibitory activity against human colon cancer and human liver cancer cells, along with immunostimulatory effects. Among them, AP-FS exhibited the highest activity level. Finally, we further investigated the underlying mechanism behind the effect of AP-FS on RAW 264.7 cells using proteomics analysis. Our findings revealed that AP-FS triggers RAW 264.7 macrophage activation via NOD-like receptor (NLR), NF-κB, and mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, our research contributes to a better understanding of the structure-function relationship among apple pectins, and AP-FS has the potential to be applied to dietary supplements targeting immunomodulation.

Effects of different extraction methods on the physico-chemical characteristics and biological activities of polysaccharides from Clitocybe squamulosa

This study comparatively evaluated the effects of the commonly used six extraction methods (acidic, alkaline, enzymatic, ultrasonic, high-pressure, and microwave) on the physico-chemical properties, processing characteristics, and biological activities of polysaccharides from Clitocybe squamulosa (CSFPs). The results show that polysaccharides extracted using an enzyme-assisted extraction method has a relatively high extraction yield (4.46 ± 1.62 %) and carbohydrate content (70.79 ± 6.25 %) compared with others. Furthermore, CSFPs were all composed of glucose, galactose, mannose, xylose, and glucosamine hydrochloride. Only ultrasonic-assisted extraction of polysaccharides (CSFP-U) has a triple helix chain conformation. Scanning electron microscopy (SEM) revealed significant differences in the microstructure of polysaccharides prepared using different methods. Besides that, the polysaccharides prepared by alkali extraction (CSFP-B) and high-pressure assisted extraction (CSFP-H) have good water (2.86 ± 0.29 g/g and 3.15 ± 0.29 g/g) and oil (8.13 ± 0.32 g/g and 7.97 ± 0.04 g/g) holding properties. The rheological behavior demonstrated that CSFPs solutions were typical non-Newtonian fluid. Apart from this, the antioxidant capacity (clearing DPPH (IC50 = 0.29) and ABTS free radicals (IC50 = 0.19), total reduction ability (IC50 = 3.02)) of polysaccharides prepared by the microwave-assisted extraction (CSFP-M) method was significantly higher than that of other extraction methods. By contrast, the polysaccharide prepared by acid extraction (CSFP-A) has the optimum binding capacity (bile acid salt (71.30 ± 6.78 %) and cholesterol (57.07 ± 3.26 mg/g)). The antibacterial activity of CSFPs was positively correlated with their concentration. Thus, the research results can provide a theoretical basis for the development and utilization of polysaccharides from C. squamulosa.

Effect of Lactiplantibacillus plantarum fermentation on the physicochemical, antioxidant activity and immunomodulatory ability of polysaccharides from Lvjian okra

Okra polysaccharides exhibits a range of biological activities. To date, its processing using microbial fermentation has not been explored. This study investigated the fermentation of okra juice with various lactic acid bacteria, followed by the extraction and characterization of crude polysaccharides (termed OPS-F), in contrast to their non-fermented counterpart (OPS). Changes in physicochemical properties, antioxidant activity and immunomodulatory ability were noted. The results demonstrated that OPS-F had a 7.42-12.53 % increase in total polysaccharides content compared to OPS. However, high-performance size-exclusion chromatography indicated a reduction in the molecular weight of OPS-F (7.9-9.5 × 105 Da) relative to OPS (1.66 × 106 Da). Compared to OPS, OPS-F had reduced levels of mannose, glucose, glucuronic acid and arabinose, but increased rhamnose, galacturonic acid and galactose, exhibiting enhanced solubility and lower apparent viscosity. Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis showed minimal changes in polysaccharide structure post-fermentation. Moreover, despite a decrease in antioxidant activity post-fermentation, OPS-F exhibited superior immunomodulatory potential. In conclusion, fermenting okra juice with lactic acid bacteria alters the physicochemical properties of crude polysaccharides and enhances their immunomodulatory activity, offering a promising approach for developing new functional food resources.

Impact of supplement of Qingke flours on physiochemical properties, sensory and in vitro starch digestibility of wheat bread and its enhancement by bread quality improvers

The aim is to upgrade the formulation to produce wheat bread with lower starch digestibility by supplemented with Qingke flour. Physiochemical properties of multi-scale Qingke flours were examined to select the most satisfied Qingke flour for breadmaking. Data showed multi-scale Qingke samples differed in total starch content, water/oil binding capacity, freeze-thaw stability, but had similar swelling capacity and thermodynamic properties. Addition of Qingke flours significantly reduced the total in vitro starch digestion of bread from 80% to 41% and decreased the rapidly digested starch content from 53% to 27%. However, Qingke flours caused a worse bread quality, texture and sensory e.g. lower bread specific volume (4.26-3.3 mL/g), larger hardness (398-1170 g) and chewiness (296-707 mJ). Meanwhile, hydroxypropyl methylcellulose, sodium stearoyl lactylate and transglutaminase could improve the bread quality and sensory. Lastly, results revealed Qingke-supplemented bread could generate new volatile compounds, hence having a different aroma compared to original wheat bread.

Trends in the Use of Lipases: A Systematic Review and Bibliometric Analysis

Scientific mapping using bibliometric data network analysis was applied to analyze research works related to lipases and their industrial applications, evaluating the current state of research, challenges, and opportunities in the use of these biocatalysts, based on the evaluation of a large number of publications on the topic, allowing a comprehensive systematic data analysis, which had not yet been conducted in relation to studies specifically covering lipases and their industrial applications. Thus, studies involving lipase enzymes published from 2018 to 2022 were accessed from the Web of Science database. The extracted records result in the analysis of terms of bibliographic compatibility among the articles, co-occurrence of keywords, and co-citation of journals using the VOSviewer algorithm in the construction of bibliometric maps. This systematic review analysis of 357 documents, including original and review articles, revealed studies inspired by lipase enzymes in the research period, showing that the development of research, together with different areas of knowledge, presents good results related to the applications of lipases, due to information synchronization. Furthermore, this review showed the main challenges in lipase applications regarding increased production and operational stability; establishing well-defined evaluation criteria, such as cultivation conditions, activity, biocatalyst stability, type of support and reactor; thermodynamic studies; reuse cycles; and it can assist in defining goals for the development of successful large-scale applications, showing several points for improvement of future studies on lipase enzymes.

Effects of different processing (Paozhi) on structural characterization and antioxidant activities of polysaccharides from Cistanche deserticola

In this study, five polysaccharides were extracted from processed Cistanche deserticola. The processing included crude product, enzymatic hydrolysis, hot air drying, stir-baking with wine and high-pressure steaming, and these polysaccharides were named as CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs and HPS-CDPs, respectively. The structural characteristics and biological activities were explored. The results showed that processing changed properties of C. deserticola polysaccharides. CP-CDPs had the highest brightness value L*(93.84) and carbohydrate content (61.27 %). EH-CDPs had minimum M_w (1531.50 kDa), while SBW-CDPs had maximum M_w (2526.0 kDa). Glucose was major predominant monosaccharide in CP-CDPs (89.82 %), HAD-CDPs (79.3 %), SBW-CDPs (59.41 %) and HPS-CDPs (63.86 %), while galactose was major monosaccharide in EH-CDPs (29.44 %). According to SEM, SBW-CDPs showed compact structures, while HPS-CDPs and HAD-CDPs had similar looser structure than SBW-CDPs; meanwhile, CP-CDPs showed irregular agglomeration shape and EH-CDPs was dense blocky shape. The AFM showed SBW-CDPs had the largest molecular chain than other polysaccharides. When scavenging activity reaching 50 %, the concentrations of CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs, HPS-CDPs are 2.25, 0.25, 0.75, 1.8 and 1.5 mg/mL, respectively. This study sheds light on the effects of traditional Chinese medicine processing on characteristics, bioactivities of C. deserticola polysaccharides, and provides the basis for applications in food and pharmaceutical industries.

A comparison between partially peeled hulless barley and whole grain hulless barley: beneficial effects on the regulation of serum glucose and the gut microbiota in high-fat diet-induced obese mice

Though the hypoglycemic effect of whole grain hulless barley (Hordeum vulgare L.) has been documented, whether glucose metabolism would be improved by hulless barley with moderate peeling is still unclear. The purpose of this study was to compare the differences in glucose metabolism and gut microbiota between partially (10%) peeled hulless barley (PHB) and whole grain hulless barley (WHB) intervention in obese mice induced by a high-fat diet. The results showed that both PHB and WHB interventions significantly improved the impaired glucose tolerance, fat accumulation in fat and liver tissues, and the impaired intestinal barrier in mice. The dysbiosis of gut microbiota was improved and the relative abundance of some beneficial bacteria such as genera Lactobacillus, Bifidobacterium, Ileibacterium, and norank_f__Mutibaculaceae was increased by both, PHB and WHB, interventions. Spearman correlation analysis revealed that the abundance of Bifidobacterium was negatively correlated with the area under the blood glucose curve. In conclusion, our results provide evidence that hulless barley improved the gut microbiota and impaired glucose tolerance in mice, and also showed that there was little loss of hypoglycemic effect even when hulless barley was moderately peeled.

Effect of acid hydrolysis on the structural and antioxidant characteristics of β-glucan extracted from Qingke (Tibetan hulless barley)

In this study, we explored the effect of acid hydrolysis on the molecular, structural, rheological, thermal, and antioxidant characteristics of Qingke β-glucan. The acid hydrolysis reduced the molecular weights of β-glucans from 510 to 155 KDa. The results of the structural analysis by nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction, and fourier transforms infrared (FTIR) spectroscopy indicated that acid hydrolysis did not change the primary functional groups of β-glucans. The rheological behavior of β-glucan without and with acid hydrolysis can be described as pseudoplastic and Newtonian, respectively. The DSC curves of the β-glucans with high molecular weights showed the highest transition temperature. The 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity and the reducing power of soluble β-glucans in Qingke showed a dose-dependent pattern. Meanwhile, the antioxidant activities of Qingke β-glucan of different molecular weights were similar. This study demostrated that the acid hydrolysis almost have no effect on antioxidant activity of Qingke β-glucans.

Hulless barley polyphenol extract inhibits adipogenesis in 3T3-L1 cells and obesity related-enzymes

Obesity is characterized by excessive lipid accumulation, hypertrophy, and hyperplasia of adipose cells. Hulless barley (Hordeum vulgare L. var. nudum Hook. f.) is the principal crop grown in the Qinghai-Tibet plateau. Polyphenols, the major bioactive compound in hulless barley, possess antioxidant, anti-inflammatory, and antibacterial properties. However, the anti-obesity effect of hulless barley polyphenol (HBP) extract has not been explored. Therefore, the current study assessed the impact of HBP extract on preventing obesity. For this purpose, we evaluated the inhibitory effect of HBP extract against obesity-related enzymes. Moreover, we investigated the effect of HBP extract on adipocyte differentiation and adipogenesis through 3T3-L1 adipocytes. Our results demonstrated that HBP extract could inhibit α-amylase, α-glucosidase (α-GLU), and lipase in a dose-dependent manner. In addition, HBP extract inhibited the differentiation of 3T3-L1 preadipocytes by arresting the cell cycle at the G0/G1 phase. Furthermore, the extract suppressed the expression of adipogenic transcription factors such as peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), regulating fatty acid synthase (FAS), fatty acid-binding protein 4 (FABP4), and adipose triglyceride lipase (ATGL). It was also observed that HBP extract alleviated intracellular lipid accumulation by attenuating oxidative stress. These findings specify that HBP extract could inhibit obesity-related enzymes, adipocyte differentiation, and adipogenesis. Therefore, it is potentially beneficial in preventing obesity.

Polyphenols in Highland barley tea inhibit the production of Advanced glycosylation end-products and alleviate the skeletal muscle damage

SCOPE

Highland barley tea is a kind of caffeine-free cereal tea. Previous studies have shown that it was rich in polyphenol flavonoids. Here, the effect of Highland barley tea polyphenols (HBP) on the production of advanced glycosylation end-products and alleviate the skeletal muscle damage is systematically investigated.

METHODS

and results: HBP effectively inhibited the formation of AGEs in vitro, and 12 phenolic compounds were identified. In addition, D-galactose was used to construct a mouse senescence model and intervened with different doses of HBP. It was found that high doses of HBP effectively inhibited AGEs in serum and flounder muscle species and increased muscle mass in flounder muscle; also, high doses of HBP increased the expression of the mitochondrial functional protein SIRT3 and decreased the expression of myasthenia-related proteins. Furthermore, cellular experiments showed that AGEs could significantly increase oxidative stress in skeletal muscle.

CONCLUSION

These data indicate that the relationship between the biological activity and HBP properties is relevant since Highland barley could be a potential functional food to prevent AGEs-mediated skeletal muscle damage. This article is protected by copyright. All rights reserved.

Two Novel Polysaccharides From Clitocybe squamulosa: Their Isolation, Structures, and Bioactivities

The crude polysaccharides from the fruiting bodies of Clitocybe squamulosa (CSFP) were isolated by hot-water extraction. Two novel polysaccharides, CSFP1-β and CSFP2-α, were further purified by DEAE-52 anion exchange and Sephacryl S-400 gel filtration chromatography, and the purities reached 98.44 and 97.83%, respectively. The structural characteristics and bioactivities of CSFP, CSFP1-β, and CSFP2-α were identified by the combination of chemical and instrumental analysis. Results showed that CSFP was formed by the aggregation of honeycomb spherical materials; CSFP1-β and CSFP2-α were interwoven by reticular and fibrous structures, respectively. Purified components of both CSFP1-β and CSFP2-α showed typical infrared absorption peaks of polysaccharides, and contents of nucleic acid and protein decreased significantly. Simultaneously, CSFP with a molecular weight (Mw) of 1.948 × 10⁴ Da were composed mainly of glucose, mannose, galactose, and rhamnose. CSFP1-β was composed mainly of glucose, galactose, and mannose, while CSFP2-α was composed of glucose, and both their Mw distributions were uneven. Compared with CSFP, the antioxidant activities of CSFP1-β and CSFP2-α were significantly improved (p < 0.05), and they both showed good abilities to bind free cholesterol and bile acid salts in vitro. The binding abilities of the two compounds were found to be 68.62 and 64.43%, and 46.66 and 45.05 mg/g, respectively. CSFP, CSFP1-β, and CSFP2-α had good bacteriostatic effects with a linear increasing relationship to increasing concentration. In addition, CSFP promoted the growth of RAW264.7 cells and has potential immunomodulatory, anti-inflammatory, and anti-tumor activities.

Coarse cereals modulating chronic low-grade inflammation: review

Chronic low-grade inflammation (CLGI) is closely associated with various chronic diseases. Researchers have paid attention to the comprehensive application and development of food materials with potential anti-inflammatory activity. Owing to their abundant nutrients and biological activities, coarse cereals have emerged as an important component of human diet. Increasing evidence has revealed their potential protective effects against CLGI in chronic conditions. However, this property has not been systematically discussed and summarized. In the present work, numerous published reports were reviewed to systematically analyze and summarize the protective effects of coarse cereals and their main active ingredients against CLGI. Their current utilization state was investigated. The future prospects, such as the synergistic effects among the active compounds in coarse cereals and the biomarker signatures of CLGI, were also discussed. Coarse cereals show promise as food diet resources for preventing CLGI in diseased individuals. Their active ingredients, including β-glucan, resistant starch, arabinoxylan, phenolic acids, flavonoids, phytosterols and lignans, function against CLGI through multiple possible intracellular signaling pathways and immunomodulatory effects. Therefore, coarse cereals play a crucial role in the food industry due to their health effects on chronic diseases and are worthy of further development for possible application in modulating chronic inflammation.

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.

In vitro digestion and fermentation by human fecal microbiota of polysaccharides from Clitocybe squamulose

The present study aimed to evaluate the effects of in vitro simulated saliva-gastrointestinal digestion and fecal fermentation behavior on the chemical composition, structure and bioactivity of polysaccharides from Clitocybe squamulosa (CSFP). Results showed that gastric digestion significantly changed the chemical composition and structural properties of CSFP, such as total uronic acid, reducing sugar, molecular weight, rheological properties, particle size, and microscopic morphology. In particular, the molecular weight decreased from 19,480 Da to 10,945 Da, while the reducing-sugar content increased from 0.149 mg/mL to 0.293 mg/mL. Gastric digestion also affected the biological activity of CSFP. Although after gastric digestion, CSFP retained its vigorous antioxidant activity, ability to inhibit α-amylase activity, and the binding ability to bile acid, fat, and free cholesterol in vitro. However, there was an apparent weakening trend. After in vitro fermentation of gut microbiota, the content of total sugar was significantly decreased from 11.6 mg/mL to 2.4 mg/mL, and the pH value in the fecal culture significantly decreased to 5.20, indicating that CSFP could be broken down and utilized by gut microbiota. Compared to the blank, the concentrations of total short-chain fatty acids (SCFAs) including acetic, propionic and n-butyric significantly increased. Simultaneously, CSFP could remarkably reduce the proportions of Firmicutes and Bacteroides (F/B) and promote the growth of some beneficial intestinal microbiota. Therefore, CSFP can potentially be a new functional food as prebiotics to promote human gut health.

Fermentation profile, cholesterol-reducing properties and chemopreventive potential of β-glucans from Levilactobacillus brevis and Pediococcus claussenii - a comparative study with β-glucans from different sources

The aim of the present study was to investigate whether β-glucans obtained from the lactic acid bacteria (LAB) Levilactobacillus (L.) brevis and Pediococcus (P.) claussenii exhibit similar physiological effects such as cholesterol-binding capacity (CBC) as the structurally different β-glucans from oat, barley, and yeast as well as curdlan. After in vitro fermentation, fermentation supernatants (FSs) and/or -pellets (FPs) were analyzed regarding the concentrations of short-chain fatty acids (SCFAs), ammonia, bile acids, the relative abundance of bacterial taxa and chemopreventive effects (growth inhibition, apoptosis, genotoxicity) in LT97 colon adenoma cells. Compared to other glucans, the highest CBC was determined for oat β-glucan (65.9 ± 8.8 mg g^-1, p < 0.05). Concentrations of SCFA were increased in FSs of all β-glucans (up to 2.7-fold). The lowest concentrations of ammonia (down to 0.8 ± 0.3 mmol L^-1) and bile acids (2.5-5.2 μg mL^-1) were detected in FSs of the β-glucans from oat, barley, yeast, and curdlan. The various β-glucans differentially modulated the relative abundance of bacteria families and reduced the Firmicutes/Bacteroidetes ratio. Treatment of LT97 cells with the FSs led to a significant dose-dependent growth reduction and increase in caspase-3 activity without exhibiting genotoxic effects. Though the different β-glucans show different fermentation profiles as well as cholesterol- and bile acid-reducing properties, they exhibit comparable chemopreventive effects.

Plant/algal polysaccharides extracted by microwave: A review on hypoglycemic, hypolipidemic, prebiotic, and immune-stimulatory effect

Microwave-assisted extraction (MAE) is an emerging technology to obtain polysaccharides with an extensive spectrum of biological characteristics. In this study, the hypoglycemic, hypolipidemic, prebiotic, and immunomodulatory (e.g., antiinflammatory, anticoagulant, and phagocytic) effects of algal- and plant-derived polysaccharides rich in glucose, galactose, and mannose using MAE were comprehensively discussed. The in vitro and in vivo results showed that these bioactive macromolecules with the low digestibility rate could effectively alleviate the fatty acid-induced lipotoxicity, acute hemolysis, and dyslipidemia status. The optimally extracted glucomannan- and glucogalactan-containing polysaccharides revealed significant antidiabetic effects through inhibiting α-amylase and α-glucosidase, improving dynamic insulin sensitivity and secretion, and promoting pancreatic β-cell proliferation. These bioactive macromolecules as prebiotics not only improve the digestibility in gastrointestinal tract but also reduce the survival rate of pathogens and tumor cells by activating macrophages and producing pro-inflammatory biomarkers and cytokines. They can effectively prevent gastrointestinal disorders and microbial infections without any toxicity.

Qingke β-glucan synergizes with a β-glucan-utilizing Lactobacillus strain to relieve capsaicin-induced gastrointestinal injury in mice

Capsaicin (CAP) is the main pungent component in capsicum fruits. Eating too much CAP leads to gastrointestinal injury. Previously, Qingke β-glucan combined with β-glucan-utilizing Lactobacillus plantarum S58 (LP.S58) ameliorated high fat-diet-induced obesity, but their effects on CAP-induced gastrointestinal injury have not been investigated. Our results showed that Qingke β-glucan reduced the CAP-induced gastrointestinal injury in Kunming mice. The serum levels of inflammatory cytokines and gastrointestinal hormones, and the localized inflammation and the expression of EGF, EGFR, VEGF, and ZO-1 in the gastrointestinal tissues in CAP-treated mice were partly restored by Qingke β-glucan. The CAP-induced increase in the abundances of proinflammatory intestinal bacteria was also reduced by Qingke β-glucan. More importantly, we found that these beneficial effects of Qingke β-glucan were markedly enhanced by β-glucan-utilizing LP.S58 supplementation. Our study indicated that Qingke β-glucan coupled with β-glucan-utilizing LP.S58 relieved CAP-induced gastrointestinal injury.

Comprehensive Evaluation of the Effect of Ultraviolet Stress on Functional Phytochemicals of Hulless Barley (Qingke) Grass in Different Growth Times at Vegetative Stage

The present study was executed to analyze the functional phytochemicals of hulless barley grass grown under different intensities of ultraviolet stress. The wheat seedlings were imposed to 0.5, 1.0, 1.5, 2.0, and 2.5 h ultraviolet radiation and harvested in different times at vegetative stage. Specifically, the contents of total polyphenols, total flavonoids, total triterpenes, total polysaccharides, proanthocyanidins, and chlorophyll were determined and antioxidants capacity was evaluated by OH^• and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging ability. A mathematical model (Technique for Order Preference by Similarity to Ideal Solution, TOPSIS) was also employed for the comprehensive evaluation of functional components of hulless barley grass at different growth stages. The results showed that the UV stress could efficiently improve/preserve the contents of total polyphenols, total flavonoids, total triterpenes, total polysaccharides, proanthocyanidins, chlorophyll a, chlorophyll b, and total chlorophyll, as well as the OH^• and ABTS scavenging capacity. TOPSIS evaluation revealed that the highest phytochemical contents were yield on the 15th day under 1.0 h ultraviolet treatment.

Interactive effects of molecular weight and degree of substitution on biological activities of arabinoxylan and its hydrolysates from triticale bran

Arabinoxylan (AX) has many beneficial health effects that are closely related to its structural characteristics. The current study aimed to investigate the effects of molecular weight (Mw) and degree of substitution (DS) on the antioxidant and hypoglycemic activities of triticale bran AX and its hydrolysates in vitro. At low and similar Mw, the antioxidant activity of AX was inversely proportional to its DS. When DS was close, the antioxidant activity of AX was inversely proportional to its Mw at high DS, but the opposite result was found at low DS. As for the hypoglycemic performance, when DS was similar, the hypoglycemic activity of AX was proportional to its Mw. At low and similar Mw, the α-glucosidase inhibitory ability and glucose adsorption ability of AX was positively correlated with DS, whereas the α-amylase inhibitory ability and glucose delayed absorption ability showed the opposite results. Mw and DS had significant effects on the antioxidant and hypoglycemic activities of AX, and these two factors often need to be combined to explain the varied effects under different conditions.

Molecular Mechanism of Functional Ingredients in Barley to Combat Human Chronic Diseases

Barley plays an important role in health and civilization of human migration from Africa to Asia, later to Eurasia. We demonstrated the systematic mechanism of functional ingredients in barley to combat chronic diseases, based on PubMed, CNKI, and ISI Web of Science databases from 2004 to 2020. Barley and its extracts are rich in 30 ingredients to combat more than 20 chronic diseases, which include the 14 similar and 9 different chronic diseases between grains and grass, due to the major molecular mechanism of six functional ingredients of barley grass (GABA, flavonoids, SOD, K-Ca, vitamins, and tryptophan) and grains (β-glucans, polyphenols, arabinoxylan, phytosterols, tocols, and resistant starch). The antioxidant activity of barley grass and grain has the same and different functional components. These results support findings that barley grain and its grass are the best functional food, promoting ancient Babylonian and Egyptian civilizations, and further show the depending functional ingredients for diet from Pliocene hominids in Africa and Neanderthals in Europe to modern humans in the world. This review paper not only reveals the formation and action mechanism of barley diet overcoming human chronic diseases, but also provides scientific basis for the development of health products and drugs for the prevention and treatment of human chronic diseases.

Effects of simulated saliva-gastrointestinal digestion on the physicochemical properties and bioactivities of okra polysaccharides

This study was to investigate the effects of in vitro simulated saliva-gastrointestinal digestion on the physicochemical properties and bioactivities of okra polysaccharides (OPS). Results showed that the digestibilities of OPS were about 5.1%, 37.5%, and 41.3% after saliva digestion (SD), saliva-gastric digestion (SGD), and saliva-gastrointestinal digestion (SGID), respectively. The SGID significantly changed the physicochemical properties of OPS, such as total uronic acids, total flavonoids, monosaccharide composition, rheological properties, and molecular weights (M_w). Especially, M_w changes resulted in the breakdown of glycosidic bonds during SGD, and the degradation of OPS during SGID was mainly caused by disrupting aggregates. Furthermore, the bioactivities of OPS were also affected by SGID. After SGID, OPS still possessed strong antioxidant activities, binding capacities, and prebiotic activities, but the α-glucosidase inhibitory effect was obviously decreased. Overall, results can provide valuable and scientific support on the oral administration of OPS as functional foods and medicines in the future.

Structural characterization, antioxidant activity, and immunomodulatory activity of non-starch polysaccharides from Chuanminshen violaceum collected from different regions

Chuanminshen violaceum has been used as an important traditional Chinese medicine and a popular tonic food in China. Polysaccharides are considered the major bioactive components in C. violaceum. In this study, in order well understand the chemical structures and bioactivities of non-starch polysaccharides in C. violaceum (CVPs), the physicochemical structures, antioxidant activities, and immunomodulatory activities of CVPs in C. violaceum collected from different regions of China were investigated and compared. Results showed that the constituent monosaccharides and Fourier transform infrared spectra of CVPs in C. violaceum collected from different regions were similar. However, their molar ratios of constituent monosaccharides, molecular weights, and contents of uronic acids were different. Furthermore, CVPs exerted remarkable antioxidant activities (ABTS and nitric oxide radical scavenging capacities) and immunomodulatory activities (promoted production of nitric oxide, IL-6, and TNF-α from RAW 264.7 macrophages in vitro). Meanwhile, the antioxidant and immunomodulatory activities of CVPs extracted from C. violaceum also varied by cultivated regions. Moreover, results indicated that the antioxidant and immunomodulatory activities of CVPs were closely correlated to their α-1,4-d-galactosiduronic linkages. Results are helpful for better understanding of the structure-bioactivity relationships of CVPs, and beneficial for the improvement of their applications in pharmaceutical and functional food industries.

Structural characteristics, rheological properties, and biological activities of polysaccharides from different cultivars of okra (Abelmoschus esculentus) collected in China

In order to well understand the physicochemical characteristics and biological activities of polysaccharides (OPPs) from different cultivars of okra collected in China, the chemical characteristics, rheological properties, antioxidant activities, in vitro binding properties, and in vitro inhibitory effects on α-glucosidase of polysaccharides from five representative okra cultivars, including 'Lvjian', 'Kalong8', 'Shuiguo', 'Taiwanwufu', and 'Kalong3', were investigated and compared. Results showed that the constituent monosaccharides of OPPs were similar, which composed of rhamnose, galacturonic acid, galactose, and arabinose. However, their weight-average molecular weights varied from 2.76 × 10³ to 4.20 × 10³ kDa, and from 0.11 × 10³ to 0.90 × 10³ kDa, respectively. The uronic acids and degrees of esterification of OPPs ranged from 39.32% to 61.68%, and from 21.66% to 30.02%, respectively. OPPs exhibited typical shear-thinning behavior and viscoelastic properties. Furthermore, OPPs exhibited remarkable antioxidant activities, in vitro binding capacities, and inhibitory effects on α-glucosidase, which might be attributed to their relatively high content of uronic acids, high degrees of esterification, and high molecular weights. Results are helpful for better understanding of the physicochemical structures and bioactivities of OPPs, and OPPs had good application prospects as functional food ingredients for industrial applications.

Extraction Optimization, Structural Characterization, and Antioxidant Activities of Polysaccharides from Cassia Seed (Cassia obtusifolia)

In order to explore Cassia seed polysaccharides (CSPs) as natural antioxidants for application in the functional-food industry, microwave-assisted extraction (MAE) was optimized for the extraction of CSPs by using a response surface methodology. Furthermore, the chemical structures and antioxidant activities of CSPs extracted by MAE and hot water extraction were investigated and compared. The maximum extraction yield of CSPs extracted by MAE (8.02 ± 0.19%) was obtained at the optimized extraction parameters as follows: microwave power (415 W), extraction time (7.0 min), and ratio of water to raw material (51 mL/g). Additionally, the contents of the uronic acids, molecular weight, ratio of constituent monosaccharides, intrinsic viscosities, and degrees of esterification of CSPs were significantly affected by the MAE method. Moreover, CSPs exhibited remarkable 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ABTS, 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl DPPH, nitric oxide, and hydroxyl radical scavenging activities as well as reducing power. The high antioxidant activities observed in CSPs extracted by MAE could be partially attributed to its low molecular weights and high content of unmethylated galacturonic acid. Results indicate that the MAE method could be an efficient technique for the extraction of CSPs with high antioxidant activity, and CSPs could be further explored as functional food ingredients.