Structural characterization of a novel glycoprotein in wheat germ and its physicochemical properties

Glycoprotein from Sargassum fusiforme exhibiting anti-inflammatory responses in vitro and in vivo via modulation of TLR4/MyD88 and NF-κB signaling

This study focuses on the identification and characterization of a glycoprotein from Sargassum fusiforme (Harvey) Setchell (SFGP), as well as investigating its potential anti-inflammatory properties both in vitro and in vivo, along with the underlying mechanism. SDS-PAGE analysis revealed a prominent band with a molecular weight of <10 kDa, consisting of 58.39 % protein and 41.61 % carbohydrates, which was confirmed through glycoprotein staining and Coomassie blue staining. Various analytical techniques, including high-resolution mass spectrometry (HRMS), FTIR, amino acid analysis, and UV-visible spectrometry, provided evidence for the presence of monosaccharides (such as d-glucose and mannose) and 17 amino acids linked by an O-glycopeptide bond. In vitro and in vivo studies were conducted to assess the anti-inflammatory activities of SFGP. The results demonstrated that SFGP effectively attenuated nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in LPS-treated RAW264.7 cells. Moreover, SFGP administration significantly and dose-dependently suppressed TLR4/MyD88 signaling as well as the phosphorylation of MAPKs, IκB, and NF-κB, leading to a reduction in the production of TNF-α, IL-1β, and IL-6 in LPS-stimulated RAW264.7 cells. Furthermore, the anti-inflammatory efficacy of SFGP was validated in a carrageenan-induced inflammatory mouse model. These findings indicate that SFGP exhibits anti-inflammatory characteristics and has the potential to be utilized as a novel anti-inflammatory agent.

The ethnopharmacology, phytochemistry and pharmacology of the genus Hericium

ETHNOPHARMACOLOGICAL RELEVANCE

Mushrooms in the genus Hericium are used as functional food and traditional medicines for a long history in East Asian countries such as China, India, Japan, and Korea. Some species of Hericium are called as monkey head mushroom (Houtougu) in China and Yamabushitake in Japan, which are traditionally considered as rare and precious health promoting food and medicinal materials for the treatment of dyspepsia, insomnia, chronic gastritis, and digestive tract tumors.

THE AIM OF THE REVIEW

This review aims to summarize the ethnopharmacology and structural diversity of secondary metabolites from Hericium species, as well as the pharmacological activities of the crude extracts and pure compounds from Hericium species in recent years.

MATERIALS AND METHODS

All the information was gathered by searching Scifinder, PubMed, Web of Science, ScienceDirect, Springer, Wiley, ACS, CNKI, Baidu Scholar, Google Scholar databases and other published materials (books and Ph.D. and M. Sc. Dissertations) using the keywords "Hericium", "Traditional uses", "Chemical composition", "Quality control" and "Pharmacological activity" (1971-May 2023). The species name was checked with https://www.mycobank.org/.

RESULTS

The traditional uses of Hericium species were summarized, and 230 secondary metabolites from Hericium species were summarized and classified into six classes, mainly focusing on their chemical diversity, biosynthesis, biological activities. The modern pharmacological experiments in vivo or in vitro on their crude and fractionated extracts showed that the chemical components from Hericium species have a broad range of bioactivities, including neuroprotective, antimicrobial, anticancer, α-glucosidase inhibitory, antioxidant, and anti-inflammatory activities.

CONCLUSIONS

The secondary metabolites discovered from Hericium species are highly structurally diverse, and they have the potential to be rich resources of bioactive fungal natural products. Moreover, the unveiled bioactivities of their crude extracts and pure compounds are closely related to critical human health concerns, and in-depth studies on the potential lead compounds, mechanism of pharmacological effects and pharmaceutical properties are clearly warranted.

Fermented Wheat Germ Alleviates Depression-like Behavior in Rats with Chronic and Unpredictable Mild Stress

Depression is a chronic mental illness with devastating effects on a person's physical and mental health. Studies have reported that food fermentation with probiotics can enrich the nutritional values of food and produce functional microorganisms that can alleviate depression and anxiety. Wheat germ is an inexpensive raw material that is rich in bioactive ingredients. For example, gamma-aminobutyric acid (GABA) is reported to have antidepressant effects. Several studies concluded that Lactobacillus plantarum is a GABA-producing bacteria and can alleviate depression. Herein, fermented wheat germs (FWGs) were used to treat stress-induced depression. FWG was prepared by fermenting wheat germs with Lactobacillus plantarum. The chronic unpredictable mild stress (CUMS) model was established in rats, and these rats were treated with FWG for four weeks to evaluate the effects of FWG in relieving depression. In addition, the study also analyzed the potential anti-depressive mechanism of FWG based on behavioral changes, physiological and biochemical index changes, and intestinal flora changes in depressed rats. The results demonstrated that FWG improved depression-like behaviors and increased neurotransmitter levels in the hippocampus of CUMS model rats. In addition, FWG effectively altered the gut microbiota structure and remodeled the gut microbiota in CUMS rats, restored neurotransmitter levels in depressed rats through the brain-gut axis, and restored amino acid metabolic functions. In conclusion, we suggest that FWG has antidepressant effects, and its potential mechanism may act by restoring the disordered brain-gut axis.

Application of enzymes in the preparation of wheat germ polypeptides and their biological activities

Wheat germ, a byproduct of wheat industrial processing, contains 30% protein and is a comprehensive source of plant-based protein. But a large amount of wheat germs are disposed of as waste every year. Wheat germ protein can be hydrolyzed into polypeptides with antioxidant, antihypertensive, anti-tumor, bacteriostatic and other activities. At present, researches on the hydrolysis of wheat germ protein and the preparation of bioactive peptides from wheat germ protein have attracted increasing attentions. However, the traditional protein hydrolysis method, protease hydrolysis, can no longer meet the market's needs for efficient production. Various auxiliary means, such as ultrasound, microwave and membrane separation, were applied to boost the yield and biological activity of wheat germ peptides by enzymatic hydrolysis. Under ultrasound and microwave, the protein structure may expand to increase the binding sites between enzyme and substrate and promote hydrolysis efficiency. Membrane separation is applied to separate products from enzymatic hydrolysate to reduce the inhibitory effect of the product on the hydrolysis reaction. The paper reviewed the hydrolysis methods of wheat germ protein and summarized the biological activity of wheat germ peptides to provide references for further study of wheat germ peptides.

A glycoprotein from mountain cultivated ginseng: Insights into their chemical characteristics and intracellular antioxidant activity

A glycoprotein (MGP2) from mountain-cultivated ginseng (MCG) was purified by Tris-HCl extraction followed by DEAE-52 ion exchange chromatography and Sephadex G-100 gel filtration chromatography. The approximate molecular weight (27.0 kDa) and monomeric nature were determined by reduced and non-reduced SDS-PAGE. The structure of MGP2 was characterized by a practical and reliable "protein-polysaccharide analyzed by spectroscopy combined with chemical analysis" strategy. The results showed that MGP2 belonged to Arabinogalactan proteins (AGPs) which contained high amount of Glc (35.1 %). The hemagglutination test concluded that MGP2 was not a lectin. In addition, the MGP2 exhibited antioxidant activity by scavenging radical capacity tests and the ability to protect human erythrocytes and RAW264.7 cells from oxidative damage induced by AAPH. Therefore, these results suggested that glycoprotein MGP2 could be used as a natural antioxidant in drug and food industry.

Regulation of wheat germ polysaccharides in the immune response of mice from newborn to adulthood associated with intestinal microbiota

The aim of this study was to determine the effects of wheat germ polysaccharides (WGPs), which are indigestible carbohydrate fibers, on mice in early life, and the changes leading to long-lasting consequences. We determined the influences of early life ceftriaxone and WGP treatment on intestinal microbiota and immunity both in newborn and adulthood mice. The results showed that ceftriaxone significantly altered the intestinal microbiota, short-chain fatty acids' (SCFAs) metabolism, organ index, and serum OVA-specific IgE levels in newborn mice. Comparing adulthood mice to ceftriaxone-treated mice, the diversity and composition of intestinal microbiota were significantly improved after WGP treatment. In addition, the levels of OVA-specific IgE in the WGP-treated mice were significantly decreased, and the expression of cytokines (IL-2, IL-4, IL-6, IFN-γ, and TNF-α) were obviously increased. Therefore, we speculate that the mechanism of action of the indigestible carbohydrate fibers of WGPs is through maintaining immune homeostasis in newborns, which may partly last into adulthood. More importantly, this may be closely related to alterations in the intestinal microbiota.

Wheat germ glycoprotein regionally modulates immunosuppressed mouse intestinal immunity function from early life to adulthood

Wheat germ glycoprotein (WGP) is widely used due to its nutritional benefits and biological activity. This study evaluated the effects of WGP on intestinal-immunosuppressed mice from early life to adulthood and detected the underlying mechanism. The results revealed that WGP demonstrated no clinical side effects on the body index, serum total IgA level, protein expression and the morphology of intestine in newborn mice. In the phase of life, compared with the cyclophosphamide-treated group (CG), WGP clearly promoted the secretion of sIgA and effectively regulated the cytokine gene (IL-2, IFN-γ, TNF-α, IL-4, IL-6, IL-5, IL-17, and TGF-β1) expression in the intestine. Furthermore, WGP promoted the expression of CD40L and CD40, phosphorylation of IKKα/β and transcription of NF-κB-p65. The data as reported in this present analysis suggest that WGP can improve the intestinal immunity of newborn mice to adulthood via the CD40L-CD40-IKKα/β-NF-κB p65 signaling pathway.

A novel wheat germ polysaccharide: Structural characterization, potential antioxidant activities and mechanism

A wheat germ polysaccharide (WGP-1) was isolated from wheat germ through hot-water (pH = 7.3) extraction and further fractionated by anion-exchange column using DEAE-52 cellulose column and purified by gel-permeation chromatography using Sephacryl S-500 column. WGP-1 was mainly consisted with rhamnose, arabinose, xylose, mannose, galactose and glucose, and linked with 1→, 1 → 2, 1 → 4, 1 → 3 and 1 → 6 glucosidic bands. The present study was designed to evaluate the antioxidant activities of WGP-1 in oleic acid (OA)-induced HepG2 cell model with its related mechanisms. Results showed that WGP-1 remarkably elevated the expression of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and total antioxidant capacity (T-AOC), and decreased the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in OA-treated cell. WGP-1 was found to promote the expression of PI3K, the phosphorylation of AKT and the translocation of Nrf2, further increased the expression of HO-1 in OA-induced cells. These results demonstrate again that WGP-1 can effectively improve OA-induced oxidative damage, probably by up-regulating of PI3K expression, Nrf2 translocation, and AKT phosphorylation.

Structure and hypoglycemic activity of a novel exopolysaccharide of Cordyceps militaris

A novel neutral exopolysaccharide (EPS-III) was isolated from culture broth of Cordyceps militaris (C. militaris). The EPS-III was a homogeneous polysaccharide with M_w of 1.56 × 10³ kDa. The yield of EPS-III from culture broth was 123.2 ± 3.1 mg/L and the sugar content was 93.32 ± 0.87%. The backbone of EPS-III was mainly consisted of →4)-α-D-Galp-(1→, while →3, 6)-α-D-Manp-(1→, →4)-α-D-Manp-(1→, →3)-β-D-Galp-(1→ and →3)-α-D-Glcp-(1→ were distributed in the backbone or in the branch chains. The EPS-III had helix structure when dissolved in weak alkaline solution. It also had branched and intertwined form on the surface. The inhibition of α-glucosidase significantly increased as the increase of purity of exopolysaccharides. The EPS-III had effective inhibition on the α-glucosidase with dose-effect relationship. Besides, the results of hypoglycemic activity analysis in vivo indicated that EPS-III can alleviate weight loss, reduce plasma glucose concentration, improve glucose tolerance, protect immune organs and repair dyslipidemia to relieve diabetes in STZ-induced diabetic mice. The manuscript first studied the hypoglycemic activity of exopolysaccharide of by C. militaris, proving and promoting the application value of culture broth. The structure characterization of EPS-III laid experimental foundations on the exploration of structure-activity relationship.