Characterization and anti-inflammation of a polysaccharide produced by Chaetomium globosum CGMCC 6882 on LPS-induced RAW 264.7 cells

A systematic review on polysaccharides from Morinda officinalis How: Advances in the preparation, structural characterization and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Morinda officinalis How is called "Ba-Ji-Tian" in Traditional Chinese Medicine (TCM), which belongs to the genus Rubiaceae and is widely used for medicinal purposes in China and other eastern Asian countries. Morinda officinalis How polysaccharides (MOPs) are one of the key bioactive components, and have a variety of biological activities, such as antioxidation, antifatigue, enhanced immunity, antiosteoporosis, ect.

AIM OF THE REVIEW

This review is aimed at providing comprehensive information of the latest preparation technologies, structural characterization, and pharmacological effects of MOPs. A more in-depth research on the structure and clinical pharmacology of the MOPs was explored. It could lay a foundation for further investigate the pharmacological activities and guide the safe clinical practice of MOPs.

MATERIALS AND METHODS

The Web of Science, PubMed, Scifinder, Google Scholar, CNKI, Wanfang database, and other online database are used to search and collect the literature on extraction and separation methods, structural characterization, and pharmacological activities of MOPs publisher from 2004 to 2023. The key words are "Morinda officinalis polysaccharides", "extraction", "isolation", "purification" and "pharmacological effects".

RESULTS

Morinda officinalis has been widely used in tonifying the kidney yang since ancient times, and is famous for one of the "Four Southern Medicines" in China for the treatment of depression, osteoporosis, rheumatoid arthritis, infertility, fatigue and Alzheimer's disease. The active ingredients of Morinda officinalis that have been researched on the treatment of depression and osteoporosis are mostly polysaccharides and oligosaccharides. The content of polysaccharides varies with different methods of extraction, separation and purification. MOPs have a wide range of pharmacological effects, including antioxidant, antifatigue, immunomodulatory, antiosteoporosis, and regulation of spermatogenesis activities. These pharmacological properties lay a foundation for the treatment of oxidative stress, osteoporosis, spermatogenic dysfunction, immunodeficiency, inflammation and other diseases with MOPs.

CONCLUSIONS

At present, MOPs have been applied in the treatment of skeletal muscle atrophy, varicocele, osteoporosis, because of its effects of enhancing immunity, improving reproduction and antioxidant. However, the structure-activity relationship of these effects are still not clear. The more deeply study could be conducted on the MOPs in the future. The toxicology and clinical pharmacology, as well as mechanism of action of MOPs were also needed to deeply studied and clarified. This paper could lay the foundation for the application and safety of MOPs in multifunctional foods and drugs.

Improvement of antibacterial activity of polysaccharides via chemical modification: A review

Antibiotic residue and bacterial resistance induced by antibiotic abuse have seriously threatened food safety and human healthiness. Thus, the development and application of safe, high-efficiency, and environmentally friendly antibiotic alternatives are urgently necessary. Apart from antitumor, antivirus, anti-inflammatory, gut microbiota regulation, immunity improvement, and growth promotion activities, polysaccharides also have antibacterial activity, but such activity is relatively low, which cannot satisfy the requirements of food preservation, clinical sterilization, livestock feeding, and agricultural cultivation. Chemical modification not only provides polysaccharides with better antibacterial activity, but also promotes easy operation and large-scale production. Herein, the enhancement of the antibacterial activity of polysaccharides via acetylation, sulfation, phosphorylation, carboxymethylation, selenation, amination, acid graft, and other chemical modifications is reviewed. Meanwhile, a new trend on the application of loading chemically modified polysaccharides into nanostructures is discussed. Furthermore, possible limitations and future recommendations for the development and application of chemically modified polysaccharides with better antibacterial activity are suggested.

Effect of monosaccharide composition and proportion on the bioactivity of polysaccharides: A review

Polysaccharides have been widely used in pharmaceutical and food industries due to their diverse bioactivity, high safety, and few or no side effects. However, inability to quickly produce, screen, and synthesize bioactive polysaccharides is the limiting factor for their development and application. Structural features determine and influence the bioactivity of polysaccharides. Among them, monosaccharide is the basic unit of polysaccharide, which not only affects electrification, functional group, and bioactivity of polysaccharide but also is one of the simplest polysaccharide indexes to be detected. At present, effects of monosaccharide composition and proportion on anti-inflammatory, antioxidant, antitumor, immunomodulatory, antibacterial, and prebiotic activities of polysaccharides are reviewed. Further problems need to be considered during regulation and analysis of monosaccharide composition and proportion of polysaccharides. Overall, present work will provide help and reference for production, development, and structure-function investigation of polysaccharides based on their monosaccharide.

Antibacterial activity of a polysaccharide isolated from Artemisia argyi leaf against Staphylococcus aureus and mechanism investigation

Abuse of antibiotics has led to excessive amounts of antibiotic residues in food and environment, thus enhancing pathogenic bacterium resistance and threatening human health. Therefore, searching and developing safe and green antibiotic alternatives are necessary. In this study, an Artemisia argyi leaf polysaccharide (AALP) fraction was extracted and analyzed. Chemical composition analysis showed that the carbohydrate, uronic acid, protein, and polyphenol content in AALP were 68.3 % ± 4.13 %, 9.4 % ± 0.86 %, 1.79 % ± 0.27 %, and 0.16 % ± 0.035 %, respectively. Chromatographic results suggested that AALP contained rhamnose, arabinose, glucosamine, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid in a molar ratio of 9.26, 1.35, 1.18, 3.04, 48.51, 2.33, 31.26, 3.93, and 9.08; the weight average molecular weight, number average molecular weight, and polydispersity of AALP were 5.41 kDa, 4.63 kDa, and 1.168, respectively. Fourier transform infrared spectroscopy indicated that AALP constituted the polysaccharide-specific groups of CH, CO, and OH. Meanwhile, AALP showed a dose-dependent inhibitory effect on Staphylococcus aureus in the inhibition zone assay, and the minimal inhibitory concentration was 1.25 mg/mL. Furthermore, AALP disrupted the cell wall, depolarized the inner membrane potential, and inhibited the activities of succinate dehydrogenase and malate dehydrogenase in S. aureus.

In vitro antioxidant analysis of flavonoids extracted from Artemisia argyi stem and their anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7 macrophages

In this study, flavonoids were successfully extracted from Artemisia argyi stem, and their yield reached 15.3 mg/g dry A. argyi stem. The flavonoid extract from A. argyi stem had a purity of 88.58 % (w/w), meanwhile, which also contained 1.57 % (w/w) carbohydrates, 2.04 % (w/w) proteins and 7.81 % (w/w) polyphenols, respectively. In vitro antioxidant activity analysis showed the increased scavenging effects of flavonoid extract from A. argyi stem on 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azinobis-di-(3-ethyl-benzothiazolin-6-sulfonic acid) diammonium salt, hydroxyl, and superoxide radicals in a concentration-dependent manner. Furthermore, the flavonoid extract from A. argyi stem exerted protective effects on lipopolysaccharide-stimulated RAW 264.7 macrophages via inhibiting the levels of tumor necrosis factor-alpha, interleukin-6, interleukin-1 beta, and nitric oxide free radicals. Overall, this work will provide guidance and help in the utilization of edible A. argyi as plant-based diet and its bioactive flavonoid extract as antioxidant and anti-inflammatory ingredients to improve the function, nutrition, and healthiness of foods.

Biochemical Characteristics and Potential Biomedical Applications of Hydrolyzed Carrageenans

Seaweed contains a variety of bioactive compounds; the most abundant of them are polysaccharides, which have significant biological and chemical importance. Although algal polysaccharides, especially the sulfated polysaccharides, have great potential in the pharmaceutical, medical and cosmeceutical sectors, the large molecular size often limits their industrial applications. The current study aims to determine the bioactivities of degraded red algal polysaccharides by several in vitro experiments. The molecular weight was determined by size-exclusion chromatography (SEC), and the structure was confirmed by FTIR and NMR. In comparison to the original furcellaran, the furcellaran with lower molecular weight had higher OH scavenging activities. The reduction in molecular weight of the sulfated polysaccharides resulted in a significant decrease in anticoagulant activities. Tyrosinase inhibition improved 2.5 times for hydrolyzed furcellaran. The alamarBlue assay was used to determine the effects of different Mw of furcellaran, κ-carrageenan and ι-carrageenan on the cell viability of RAW264.7, HDF and HaCaT cell lines. It was found that hydrolyzed κ-carrageenan and ι-carrageenan enhanced cell proliferation and improved wound healing, whereas hydrolyzed furcellaran did not affect cell proliferation in any of the cell lines. Nitric oxide (NO) production decreased sequentially as the Mw of the polysaccharides decreased, which indicates that hydrolyzed κ-Carrageenan, ι-carrageenan and furcellaran have the potential to treat inflammatory disease. These findings suggested that the bioactivities of polysaccharides were highly dependent on their Mw, and the hydrolyzed carrageenans could be used in new drug development as well as cosmeceutical applications.

Antioxidant and antibacterial activities of a polysaccharide produced by Chaetomium globosum CGMCC 6882

In the present work, a Gynostemma pentaphyllum herb endophytic fungus of Chaetomium globosum CGMCC 6882 polysaccharide produced from tapioca starch (GCP-TS) with submerged fermentation was analyzed. GCP-TS contains rhamnose, glucosamine, galactose, glucose, mannose, and glucuronic acid in the molar ratio of 6.29: 0.55: 1.12: 22.93: 10.94: 3.54. Its weight-average molecular weight, number-average molecular weight and polydispersity were 4.73 × 10⁴ Da, 4.29 × 10⁴ Da and 1.103, respectively. Antioxidant results showed that GCP-TS had a concentration-dependent scavenging ability against DPPH radical, superoxide anion, hydroxyl radical, and ABTS radical. The corresponding scavenging capacities of GCP-TS aqueous solution at the concentration of 1.0 mg/mL were 45.11 ± 2.52, 43.58 ± 1.97, 36.27 ± 2.48, and 34.39 ± 2.06 %, respectively. Antibacterial activities of GCP-TS against Staphylococcus aureus and Escherichia coli were enhanced with the increase in its concentration, and its bacteriostatic activity against S. aureus was stronger than that against E. coli.

Effect of ultrasonic degradation on the structural feature, physicochemical property and bioactivity of plant and microbial polysaccharides: A review

With the bioactivities of antioxidant, anti-bacteria, anti-inflammation, immune regulation, antitumor and anti-coagulation, plant and microbial polysaccharides have been widely used in foods, medicine and cosmetics. However, how structure features affect the physicochemical property and bioactivity of plant and microbial polysaccharides is still unclear. Ultrasonic degradation usually degrades or modifies plant and microbial polysaccharides with different physicochemical properties and bioactivities by affecting their chemical or spatial structures via mechanical bond breaking and cavitation effects. Therefore, ultrasonic degradation might be an effective strategy for producing bioactive plant and microbial polysaccharides and analyzing their structure-function relationship. Present review summarized the influence of ultrasonic degradation on structural feature, physicochemical property and bioactivity of plant and microbial polysaccharides. Moreover, further problems need to be paid attention to during the application of ultrasonication for plant and microbial polysaccharides degradation are also recommended. Overall, present review will provide an efficient method for producing enhanced bioactive plant and microbial polysaccharides and analyzing their structure-activity relationship based on ultrasonic degradation.

Research advances on endophytic fungi and their bioactive metabolites

Endophytic fungi, as a kind of fungi living in the healthy plant tissues and organs, are important sources of natural bioactive products and new microbial resources with high developing value. Therefore, exploration and utilization of endophytic fungi can not only alleviate the problems of resource shortage and ecological balance destruction caused by extracting large number of useful bioactive products from natural plants, but also benefit the protection of rare and endangered plant resources, which is of great significance and economic value. This review mainly expounds the concept of endophytic fungi, analyzes the research advances of endophytic fungi from antioxidant, antibacterial, insecticidal, regulating plant growth, anticancer and antitumor bioactivities and, furthermore, summarizes the existing problems in present research of endophytic fungi and corresponding solutions. We hope that this review could provide references for the development and utilization of endophytic fungi and their bioactive metabolites.

Structural elucidation and anti-inflammatory activity of a proteoglycan from spent substrate of Lentinula edodes

A proteoglycan LEPS1 was firstly isolated and purified from the spent substrate of Lentinula edodes, an agricultural waste that may cause environmental pollution. The average molecular weight of LEPS1 was 1.18 × 10⁴ g/mol, and carbohydrate moiety (88.9 %) was composed of glucose, arabinose, galactose, xylose and mannose at a molar ratio of 1.2:1.2:1.0:2.3:1.1. The protein moiety (8.5 %) of LEPS1 was bonded to the polysaccharide chain via O-glycosidic linkage. LEPS1 could significantly improve the inflammatory injury of LPS stimulated RAW264.7 macrophages by inhibiting the secretion of NO and decreasing the levels of pro-inflammatory factors (TNF-α, IL-1β and IL-6). LEPS1 inhibited JAK-STAT1 and p38 MAPK signaling pathway via modulating JAK expression, phosphorylation of STAT1 and phosphorylation of p38, respectively. Moreover, LEPS1 could promote the expression of CD 206 and IL-10 which were the markers for repairing macrophages. Overall, LEPS1 had anti-inflammatory activity and can potentially treat as a novel anti-inflammation agent. This work could provide scientific basis and valuable information for the highly efficient utilization of spent L. edodes substrates as the by-product in mushroom industries.

Identification of a Novel Pleiotropic Transcriptional Regulator Involved in Sporulation and Secondary Metabolism Production in Chaetomium globosum

Chaetoglobosin A (CheA), a well-known macrocyclic alkaloid with prominently highly antimycotic, antiparasitic, and antitumor properties, is mainly produced by Chaetomium globosum. However, a limited understanding of the transcriptional regulation of CheA biosynthesis has hampered its application and commercialization in agriculture and biomedicine. Here, a comprehensive study of the CgXpp1 gene, which encodes a basic helix-loop-helix family regulator with a putative role in the regulation of fungal growth and CheA biosynthesis, was performed by employing CgXpp1-disruption and CgXpp1-complementation strategies in the biocontrol species C. globosum. The results suggest that the CgXpp1 gene could be an indirect negative regulator in CheA production. Interestingly, knockout of CgXpp1 considerably increased the transcription levels of key genes and related regulatory factors associated with the CheA biosynthetic. Disruption of CgXpp1 led to a significant reduction in spore production and attenuation of cell development, which was consistent with metabolome analysis results. Taken together, an in-depth analysis of pleiotropic regulation influenced by transcription factors could provide insights into the unexplored metabolic mechanisms associated with primary and secondary metabolite production.

Neocinnamomum caudatum Essential Oil Ameliorates Lipopolysaccharide-Induced Inflammation and Oxidative Stress in RAW 264.7 Cells by Inhibiting NF-κB Activation and ROS Production

Neocinnamomum caudatum (Lauraceae) plant is used in the traditional system of medicine and is considered a potential source of edible fruits, spices, flavoring agents and biodiesel. The leaves, bark and roots of the species are used by local communities for the treatment of inflammatory responses, such as allergies, sinusitis and urinary tract infections. However, there is no scientific evidence to support the molecular mechanism through which this plant exerts its anti-inflammatory effect. The aim of the current research was to characterize the chemical constituents of bark (NCB) and leaf (NCL) essential oil of N. caudatum and to elucidate its anti-inflammatory action in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Essential oils extracted by hydrodistillation were further subjected to gas chromatography mass spectrometry (GC-MS) analysis. The major constituents in bark essential oil identified as β-pinene (13.11%), α-cadinol (11.18%) and α-pinene (10.99%), whereas leaf essential oil was found to be rich in β-pinene (45.21%), myrcene (9.97%) and α-pinene (9.27%). Treatment with NCB and NCL at a concentration of 25 µg/mL exerted significant anti-inflammatory activity by significantly reducing LPS-triggered nitric oxide (NO) production to 45.86% and 61.64%, respectively, compared to the LPS-treated group. In the LPS-treated group, the production of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β, decreased after treatment with essential oil, alleviating the mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2. The essential oil also inhibited the production of intracellular ROS and attenuated the depletion of mitochondrial membrane potential in a concentration-dependent manner. Pretreatment with NCB also reduced nuclear factor kappa-B (NF-κB)/p65 translocation and elevated the levels of endogenous antioxidant enzymes in LPS-induced macrophages. The present findings, for the first time, demonstrate the anti-inflammatory potential of both bark and leaf essential oils of N. caudatum. The bark essential oil exhibited a significantly more important anti-inflammatory effect than the leaf essential oil and could be used as a potential therapeutic agent for the treatment of inflammatory diseases.

Antioxidant and anti-inflammatory properties of an aminoglycan-rich exopolysaccharide from the submerged fermentation of Bacillus thuringiensis

Proteins from Bacillus thuringiensis are widely used as biopesticides but little is known about its exopolysaccharides. The exopolysaccharide BPS-2 was extracted from B. thuringiensis IX-01 after high-cell-density fermentation. BPS-2 is a heteropolysaccharide (molecular weight 29.36 kDa) composed of D-galactosamine, arabinose, glucosamine, glucose, and mannose in molar ratios 5.53: 1.77:4.74:3.24:1. In vitro upper gastrointestinal simulations showed that BPS-2 has strong anti-digestive capacity, with scavenging of DPPH, hydroxyl, ABTS, and superoxide anions radicals of 31.34 ± 1.67 %, 32.43 ± 3.01 %, 34.31 ± 2.12 %, and 48.53 ± 3.55 %, respectively, after BPS-2 entered the colon. It significantly inhibited production of lipopolysaccharide-induced nitric oxide and multiple pro-inflammatory cytokines and had proliferative effects on RAW 264.7 cells. BPS-2 inhibited malondialdehyde secretion and elevated activities of glutathione peroxidase, superoxide dismutase, and total antioxidants, significantly improving the antioxidant status of inflammation model cells. This first report of the in vitro anti-inflammation and antioxidant properties of BPS-2 from B. thuringiensis provides a basis for biopharmaceutical applications.

Synthesis of naphthalimide-type chemsensor and its application in quality evaluation for polygonatum sibiricum Red

The premise and key of ensuring the safety and effectiveness of traditional Chinese medicine (TCM) is to construct appropriate quality evaluation system of TCM. This study aimed to establish a pre-column derivatization HPLC method for achieving the quality control of Polygonatum sibiricum by reacting synthesized 4-hydrazino-1,8-naphthalimide (HAN) with diverse monosaccharides from the hydrolytic product of P. sibiricum polysaccharides (PSPs), followed by HPLC separation. The HAN was synthesized based on a CuI-catalyzed cross-coupling reaction in water, and then employed as a novel chemosensor that reacts with reducing sugars. Good separation was achieved at a detection wavelength of 448 nm using an ZORBAX SB-C8 column under a gradient elution at a flow rate of 0.5 ml/min within 12 min. The monosaccharide compositions of PSP mainly include two hexoses [glucose (Glc), galactose (Gal)] and two hexuronic acids [glucuronic acid (GlcA) and galacturonic acid (GalA)], and the molar ratio of Glc, Gal, GlcA and GalA is 16.67:52.94:10.58:19.81. The verified HPLC method, possessing excellent precision and good accuracy, successfully achieved rapid qualitative and quantitative determination for PSP. Additionally, the HAN displayed fluorescence enhancement through “push–pull” mode, and fluorescence decreased through “pull–pull” mode after binding to monosaccharides, which is a potential for fluorescence determination of different monosaccharides.

Effect of ultrasonic degradation on the physicochemical property and bioactivity of polysaccharide produced by Chaetomium globosum CGMCC 6882

Similar to the enzymatic process, there might also be an active fragment in polysaccharides, how to obtain is important for investigating the bioactivity and pharmacological mechanism of polysaccharides. Presently, a Gynostemma pentaphyllum endophytic fungus Chaetomium globosum CGMCC 6882 polysaccharide [Genistein Combined Polysaccharide (GCP)] was degraded by ultrasonic treatment, two polysaccharide fragments of GCP-F1 and GCP-F2 were obtained. Physicochemical results showed that GCP-F1 and GCP-F2 had the same monosaccharide composition of arabinose, galactose, glucose, xylose, mannose, and glucuronic acid as compared to GCP with slightly different molar ratios. However, weight-average molecular weights of GCP-F1 and GCP-F2 decreased from 8.093 × 10⁴ Da (GCP) to 3.158 × 10⁴ Da and 1.027 × 10⁴ Da, respectively. In vitro scavenging assays illustrated that GCP-F1 and GCP-F2 had higher antioxidant activity against 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide anions, and hydroxyl radical than GCP, the order was GCP < GCP-F1 < GCP-F2. Meanwhile, antibacterial tests showed that ultrasonic degradation increased the antibacterial activity of GCP-F1 as compared to GCP, but GCP-F2 almost lost its antibacterial activity with further ultrasound treatment. Changes in the antioxidant and antibacterial activities of GCP-F1 and GCP-F2 might be related to the variation of their molecular weights.

Chemical Structure and Immune Activation of a Glucan From Rhizoma Acori Tatarinowii

Rhizoma Acori Tatarinowii is a traditional Chinese herb used to treat depression and coronary heart disease. Studies on its active components mainly focus on small molecular compounds such as asarone and other essential oil components, while the large molecular active components such as polysaccharides are ignored. In this study, we aimed to study the chemical structure and immune activation of polysaccharides from Rhizoma Acori Tatarinowii. In this study, a polysaccharide (RATAPW) was isolated and purified by DEAE-52 cellulose and Sephadex G-100 column chromatography from alkali extraction polysaccharide of Rhizoma Acori Tatarinowii. The average molecular weight of RATAPW was 2.51 × 10⁴ Da, and the total carbohydrate contents of RATAPW were 98.23 ± 0.29%. The monosaccharide composition, methylation, and nuclear magnetic resonance (NMR) analysis results displayed that the polysaccharide was α-1,4-glucan with short α-1,6 branches. Immunofluorescence assay and inhibitor neutralization assay indicated that RATAPW could promote the TNF-α production of RAW264.7 macrophage through the nuclear factor kappa B (NF-κB) molecular signaling pathway. Treatment with 200 μg/ml of RATAPW enhanced a 38.77% rise in the proliferation rate of spleen lymphocytes. RATAPW also enhances ConA-induced T cells and lipopolysaccharide (LPS)-induced B cell proliferation in a dose-dependent effect. Our study lays a foundation for the discovery of natural polysaccharide immune modulators or functional food from Rhizoma Acori Tatarinowii.

Effects of enzymolysis and fermentation on the antioxidant activity and functional components of a coarse cereal compound powder based on principal component analysis and microstructure study

Abstract

In this study, a coarse cereal compound powder (CCCP) was prepared through enzymolysis, fermentation, and joint treatment with 10 coarse cereal types as raw materials. Using 10 evaluation indices, namely the scavenging capacity of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH•), 2,2′‐azino‐bis‐(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS⁺), hydroxyl (OH•) and superoxide anion (O₂^–), the Fe²⁺ chelating capacity, the content of anthocyanin, flavone, soluble dietary fiber, reducing sugar and protein, antioxidant activity, and functional components of CCCP prepared by different methods were compared. Principal component analysis (PCA) was performed to establish a quality evaluation model of CCCP. Then, the effects of different treatments on the microstructure of CCCP were investigated. Two principal components (PCs) were extracted from PCA, with a cumulative contribution rate of 97.014%. In addition, the analysis of thermodynamic properties indicated that the initial gelatinization temperature of CCCP decreased after enzymolysis and fermentation and that it was easier to gelatinize. Particle size analyses revealed that different treatments could reduce the sample particles to different degrees. The average particle size in the three study groups decreased. Scanning electron microscopy (SEM) revealed that after different treatments, the samples were destroyed to different extents, which facilitated easy dissolution of active substances. Fourier‐transformed‐infrared spectroscopy (FTIR) revealed that the changes of CCCP functional groups after fermentation and joint treatment were more significant than those after enzymolysis.

Practical Application

In this study, enzymolysis and fermentation techniques were used to improve the antioxidant activity and functional components of CCCP, and the effects of different treatments on the microstructure of CCCP were investigated. The bioavailability and nutrient composition of CCCP could be significantly improved by pretreatment, provide useful reference for the development of beneficial ingredients in cereal meal products and the application of different pretreatment methods.

Characterization and Antibacterial Activity of a Polysaccharide Produced From Sugarcane Molasses by Chaetomium globosum CGMCC 6882

As a by-product of the sugar industry containing many sugars, proteins, nitrogenous materials, and heavy metals, molasses is rarely used for polysaccharide production. In the present work, a Chaetomium globosum CGMCC 6882 polysaccharide was produced from sugarcane molasses (CGP-SM) was successfully produced from sugarcane molasses. The yield of CGP-SM was 5.83 ± 0.09 g/l and its protein content was 2.41 ± 0.12% (w/w). Structural analysis showed that CGP-SM was a crystalline and amorphous polysaccharide containing rhamnose, glucosamine, galactose, glucose, mannose, fructose, and glucuronic acid in the molar ratio of 10.31: 1.14: 2.07: 59.55: 42.65: 1.92: 9.63. Meanwhile, weight-average molecular weight (Mw), number-average molecular weight (Mn), and polydispersity (Mw/Mn) of CGP-SM were 28.37 KDa, 23.66 KDa, and 1.199, respectively. Furthermore, the bacteriostatic assay indicated that CGP-SM inhibited the growth of Escherichia coli and Staphylococcus aureus in a concentration-dependent manner, and its inhibitory effect on S. aureus was higher than that of E. coli. Above all, this work provides a green method for the production of bioactive polysaccharide from sugarcane molasses.

Characterization and In Vitro Fecal Microbiota Regulatory Activity of a Low-Molecular-Weight Exopolysaccharide Produced by Lactiplantibacillus plantarum NMGL2

The exopolysaccharide (EPS) produced by Lactiplantibacillus plantarum NMGL2 isolated from traditional fermented dairy cheese was purified chromatographically with DEAE-Sepharose and Sepharose CL-6B columns. The purified EPS was characterized by various physicochemical methods and in vitro fecal microbiota regulation assay. The results showed that the EPS had a relatively low molecular weight of 3.03 × 104 Da, and it had a relatively high degradation temperature of 245 °C as determined by differential scanning calorimetry. Observation of the EPS by scanning electron microscopy, transmission electron microscopy, and atomic force microscopy revealed a highly branched and tangled fibrous network microstructure with many hollow microtubules and spherical particles. Structural study by 1H NMR spectroscopy suggested that the EPS contained a tetrasaccharide repeating unit with monosaccharide components of β-galactose (4.6%), α-glucose (20.6%), and α-mannose (74.8%). The EPS was highly resistant to hydrolysis of simulated human saliva, gastric, and intestinal juices. Moreover, the EPS beneficially affected the composition and diversity of the fecal microbiota, e.g., increasing the relative abundance of Firmicutes and inhibiting that of Proteobacteria. The results of this study indicated significant bioactivity of this novel low-molecular-weight EPS produced by Lpb. plantarum NMGL2, which could serve as a bioactive agent for potential applications in the food and health care industry.

Sulfated Chinese yam polysaccharide enhances the immunomodulatory activity of RAW 264.7 cells via the TLR4-MAPK/NF-κB signaling pathway

In this study, Chinese yam polysaccharide (CYP) was isolated from yam by hydroextraction and alcoholic precipitation. Subsequently, the chlorosulfate-pyridine (CSA-Pyr) method was used to obtain the sulfated Chinese yam polysaccharide derivative (S-CYP) to evaluate its immunomodulatory activity in RAW 264.7 cells and to investigate its mechanism of action. The results revealed that the sulfated modification altered the physicochemical properties of CYP but had no impact on the main chain structure. S-CYP demonstrated excellent immunomodulatory activity by increasing the viability of RAW 264.7 macrophage cells and stimulating the production of reactive oxygen species (ROS), nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin (IL)-6. Moreover, signal transduction experiments showed that S-CYP induced the activation of mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways through toll-like receptor 4 (TLR4), dramatically increasing p-ERK, p-JNK and p-p38 proteins. Meanwhile, immunofluorescence results showed that S-CYP could significantly promote the entry of NF-κB p65 into the nucleus, which is essential for triggering the NF-κB pathway. Furthermore, blocking antibody experiments revealed that specific inhibitors of TLR4, MAPKs, and NF-κB suppressed the generation of TNF-α and IL-6 in RAW 264.7 cells. These findings suggested that both CYP and S-CYP could be used as immunomodulatory agents and may have potential application prospects in the food and pharmaceutical industries.

Anti-inflammatory activity of flavonols via inhibiting MAPK and NF-κB signaling pathways in RAW264.7 macrophages

Fisetin (Fis), quercetin (Que), and myricetin (Myr) are flavonols with similar structure but different number of hydroxyl groups. The present research focused on the anti-inflammatory effect of these three flavonols in lipopolysaccharide-stimulated RAW264.7 cells. The number and site of hydroxyl group in flavonols obviously affected their anti-inflammation activity. These flavonols suppressed the overproduction of nitric oxide. Fis showed the best activity with an inhibition rate of 52% at 20 μM. Moreover, the flavonols reduced the levels of ROS, TNF-α, and IL-6. The mechanistic study showed that they inhibited the activation of NF-κB and MAPK pathways by suppressing the phosphorylation of IκBα, p65, JNK, ERK, p38, MEK, and reducing the nuclear translocation of NF-κB p65. In addition, the metabolism of the flavonols was examined. The results indicated that Fis was both methylated and glucuronidated. Que and Myr were mainly transformed into methylated products. This study highlights the anti-inflammatory activity of flavonols, particularly Fis, which has the potential for the prevention or treatment of inflammation as an adjuvant medicine or food additive.

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Flavonols suppressed the production of NO and ROS.

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Flavonols partially blocked the activation of NF-κB and MAPK pathways.

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Fisetin is an excellent anti-inflammatory reagent.

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The number of hydroxyl group in flavonols obviously affects their anti-inflammation activity.

Structural Characterization of Sulfated Polysaccharide Isolated From Red Algae (Gelidium crinale) and Antioxidant and Anti-Inflammatory Effects in Macrophage Cells

Gelidium crinale, the red algae belonging to Geliaceae Gelidium, is a traditional edible and industrial alga in China. A sulfated polysaccharide (GNP) is successfully separated from Gelidium crinale by acid extraction and two-step column chromatography. Chemical analysis showed that the molecular weight of GNP was 25.8 kDa and the monosaccharide composition had the highest galactose content and confirmed the presence and content (16.5%) of sulfate by Fourier transform infrared spectroscopy (FT-IR) spectrometry as well as barium chloride-gelatin methods. In addition, the effect of GNP on lipopolysaccharide (LPS)-induced oxidative stress and inflammation in macrophages was also evaluated. The research results showed that GNP had fairly strong scavenging activities on 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical, hydroxyl radical, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and had Fe²⁺-chelating ability in a dose-dependent manner. At the same time, it significantly inhibits the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and the production of pro-inflammatory cytokines in RAW 264.7 cells induced by LPS through blocking the mitogen-activated protein kinase (MAPK)/nuclear factor kappa beta (NF-κB) signaling pathway. These results indicate that GNP may be a latent component anti-inflammation in pharmaceutical and functional food industries.

Chaetomium and Chaetomium-like Species from European Indoor Environments Include Dichotomopilus finlandicus sp. nov

The genus Chaetomium is a frequently occurring fungal taxon world-wide. Chaetomium and Chaetomium-like species occur in indoor environments, where they can degrade cellulose-based building materials, thereby causing structural damage. Furthermore, several species of this genus may also cause adverse effects on human health. The aims of this research were to identify Chaetomium and Chaetomium-like strains isolated from indoor environments in Hungary and Finland, two geographically distant regions of Europe with drier and wetter continental climates, respectively, and to study their morphological and physiological properties, as well as their extracellular enzyme activities, thereby comparing the Chaetomium and Chaetomium-like species isolated from these two different regions of Europe and their properties. Chaetomium and Chaetomium-like strains were isolated from flats and offices in Hungary, as well as from schools, flats, and offices in Finland. Fragments of the translation elongation factor 1α (tef1α), the second largest subunit of RNA polymerase II (rpb2) and β-tubulin (tub2) genes, as well as the internal transcribed spacer (ITS) region of the ribosomal RNA gene cluster were sequenced, and phylogenetic analysis of the sequences performed. Morphological examinations were performed by stereomicroscopy and scanning electron microscopy. Thirty-one Chaetomium sp. strains (15 from Hungary and 16 from Finland) were examined during the study. The most abundant species was Ch. globosum in both countries. In Hungary, 13 strains were identified as Ch. globosum, 1 as Ch. cochliodes, and 1 as Ch. interruptum. In Finland, 10 strains were Ch. globosum, 2 strains were Ch. cochliodes, 2 were Ch. rectangulare, and 2 isolates (SZMC 26527, SZMC 26529) proved to be representatives of a yet undescribed phylogenetic species from the closely related genus Dichotomopilus, which we formally describe here as the new species Dichotomopilus finlandicus. Growth of the isolates was examined at different temperatures (4, 15, 20, 25, 30, 37, 35, 40, and 45 °C), while their extracellular enzyme production was determined spectrophotometrically.

Probiotic yeast BR14 ameliorates DSS-induced colitis by restoring the gut barrier and adjusting the intestinal microbiota

The probiotic Saccharomyces boulardii has been widely used in colitis treatment; however, the beneficial effects of other yeast species are rarely studied. Saccharomyces cerevisiae with great stress tolerance and potential in colitis treatment was investigated in this study. Among 16 yeast strains, BR14, BR54, and BR174 strains showed good stress-resistant capacity, anti-inflammatory activity, and little toxicity to macrophages. As for the colitis mice, BR14 inhibited weight loss the most, as well as the disease activity index and colon shortening. After treatment with BR14, the expression levels of genes related to histological damage were all upregulated. BR14 significantly attenuated the expression levels of TNF-α and IL-6, while the expression of IL-10 was upregulated. Additionally, BR14 rebalanced the intestinal microbial composition of colitis mice by increasing the abundance of Muribaculaceae, Lactobacillus and Rikenellaceae and decreasing the abundance of Turicibacter, Escherichia-Shigella, Desulfovibrio, and Lachnospiraceae. In summary, BR14 exhibited great potential in alleviating colitis through restoring the gut barrier and adjusting the intestinal microbiota.