Isolation, purification and immunobiological activity of a new water-soluble bee pollen polysaccharide from Crataegus pinnatifida Bge

Isolation, structural properties and bioactivities of polysaccharides from Crataegus pinnatifida

ETHNOPHARMACOLOGIC RELEVANCE

Crataegus pinnatifida, commonly known as hawthorn, is a plant species with a long history of medicinal use in traditional Chinese medicine. Hawthorn polysaccharides (HP) have gained worldwide attention due to their decent biological activities and potential health benefits. Their excellent antioxidant activity, antitumor activity, immunomodulatory activity, hypoglycemic effect and hypolipidemic effects, intestinal microbiota modulatory activity makes them valuable in the field of ethnopharmacological research.

AIM OF THE STUDY

The purpose of the current review is to provide a systematic and comprehensive summary of the latest literatures and put forward the future perspectives on hawthorn polysaccharides in the context of its extraction, purification, structural characteristics and bioactivities. Furthermore, the underlying structure-bioactivity relationship of hawthorn polysaccharides was also explored and discussed. The current review would provide the important research underpinnings and the update the information for future development and application of hawthorn polysaccharides in the pharmaceutical and functional food industries.

MATERIALS AND METHODS

We use Google Scholar, CNKI, PubMed, Springer, Elsevier, Wiley, Web of Science and other online databases to search and obtain the literature on extraction, isolation, structural analysis and the biological activity of hawthorn polysaccharides published before October 2023. The key words are "extraction", "isolation and purification", "bioactivities", and "Crataegus pinnatifida polysaccharides ".

RESULTS

Crataegus pinnatifida has been widely used for the treatment of cardiovascular diseases, digestive disorders, inflammatory and oxidative stress in traditional Chinese medicine. Polysaccharides are the key active components of Crataegus pinnatifida which have gained widespread attention. The structure and bioactivity of polysaccharides from Crataegus pinnatifida varies in terms of raw materials, extraction methods and purification techniques. Crataegus pinnatifida polysaccharides possess diverse bioactivities, including antitumor, immunomodulatory, hypoglycemic activity, cardioprotective and antioxidant activities, among others. These biological properties can not only lay firm foundation for the treatment of diverse diseases, but also provide a theoretical basis for the in-depth study of the structure-activity relationship. In addition, the underlying structure-activity relationship is also explored and discussed, and further research and development of hawthorn polysaccharides are also prospected.

CONCLUSION

As a natural compound, hawthorn polysaccharides has garnered significant attention and held immense research potential. Hawthorn polysaccharides can be obtained through different extraction methods, including hot water extraction method, ultrasonic extraction method and enzymatic extraction method etc. The structures of hawthorn polysaccharides have also been characterized and reported in numerous studies. Moreover, hawthorn polysaccharides exhibit a wide range of bioactivities, such as the antioxidant activity, the antitumor activity, the immunomodulatory activity, the hypoglycemic effect and the hypolipidemic effect, as well as the intestinal microbiota modulatory activity. These diverse bioactivities contribute to the growing interest in hawthorn polysaccharides and its potential applications. Hawthorn polysaccharides has promising application prospects in various industries, including functional food, pharmaceuticals and biomedical research. Therefore, it is imperative to fully explore and harness the potential of hawthorn polysaccharides in the food and medicine fields.

Traditional uses, phytochemistry, pharmacology, and safety concerns of hawthorn (Crataegus genus): A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Crataegus (hawthorn), a member of the Rosaceae family, encompasses several species with broad geographical distribution across the Northern Hemisphere, including Asia, Europe, and the Americas. Hawthorn is recognized as an edible medicinal plant with applications related to strengthening the digestive system, promoting blood circulation, and resolving blood stasis.

AIM OF THE REVIEW

This study critically summarized the traditional uses, phytochemistry, and pharmacological properties to provide a theoretical basis for further studies on hawthorn and its applications in medicine and food.

MATERIALS AND METHODS

The available information on hawthorn was gathered from scientific databases (including Google Scholar, Web of Science, PubMed, ScienceDirect, Baidu Scholar, CNKI, online ethnobotanical databases, and ethnobotanical monographs, and considered data from 1952 to 2023). Information about traditional uses, phytochemistry, pharmacology, and safety concerns of the collected data is comprehensively summarized in this paper.

RESULTS

The literature review revealed that hawthorn includes more than 1000 species primarily distributed in the northern temperate zone. Traditional uses of hawthorn have lasted for millennia in Asia, Europe, and the Americas. Within the past decade, 337 chemical compounds, including flavonoids, lignans, fatty acids and organic acids, monoterpenoids and sesquiterpenoids, terpenoids and steroids, have been identified from hawthorn. Modern pharmacological studies have confirmed numerous bioactivities, such as cardiovascular system influence, antitumor activity, hepatoprotective activity, antimicrobial properties, immunomodulatory functions, and anti-inflammatory activities. Additionally, evaluations have indicated that hawthorn lacks toxicity.

CONCLUSIONS

Based on its traditional uses, chemical composition, and pharmacological studies, hawthorn has significant potential as a medicinal and edible plant with a diverse range of pharmacological activities. Traditional uses of the hawthorn include the treatment of indigestion, dysmenorrhea, and osteoporosis. However, modern pharmacological research primarily focuses on its cardiovascular and cerebrovascular system effects, antitumor effects, and liver protection properties. Currently, there is a lack of correlative research involving its traditional uses and pharmacological activities. Moreover, phytochemical and pharmacological research has yet to focus on many types of hawthorn with traditional applications. Therefore, it is imperative to research the genus Crataegus extensively.

Preparation, structural characterization, bioactivities, and applications of Crataegus spp. polysaccharides: A review

Crataegus, is a genus within the Rosaceae family. It is recognized as a valuable plant with both medicinal and edible qualities, earning it the epithet of the "nutritious fruit" owing to its abundant bioactive compounds. Polysaccharides are carbohydrate polymers linked by glycosidic bonds, one of the crucial bioactive ingredients of Crataegus spp. Recently, Crataegus spp. polysaccharides (CPs) have garnered considerable attention due to their diverse range of bioactivities, including prebiotic, hypolipidemic, anticancer, antibacterial, antioxidant, and immunobiological properties. Herein, we provide a comprehensive overview of recent research on CPs. The analysis revealed that CPs exhibited a broad molecular weight distribution, ranging from 5.70 Da to 4.76 × 108 Da, and are composed of various monosaccharide constituents such as mannose, rhamnose, and arabinose. Structure-activity relationships demonstrated that the biological function of CPs is closely associated with their molecular weight, galacturonic acid content, and chemical modifications. Additionally, CPs have excellent bioavailability, biocompatibility, and biodegradability, which make them promising candidates for applications in the food, medicine, and cosmetic industries. The article also scrutinized the potential development and future research directions of CPs. Overall, this article provides comprehensive knowledge and underpinnings of CPs for future research and development as therapeutic agents and multifunctional food additives.

Immunomodulatory Effect of Flammulina rossica Fermentation Extract on Healthy and Immunosuppressed Mice

Flammulina rossica fermentation extract (FREP) was obtained by ethanol precipitation of the fermentation broth. The molecular weight of FREP is 28.52 kDa, and it mainly contains active ingredients such as polysaccharides, proteins, reducing sugars, and 16 amino acids. Among them, the polysaccharides were mannose, glucose, galactose, arabinose, and fucose and possessed β-glycosidic bonds. Furthermore, the immunoregulatory activities of FREP were investigated in vivo. The results demonstrated that FREP could increase the counts of CD4+ T lymphocytes and the ratio of CD4+/CD8+ in a dose-dependent manner in healthy mice. In addition, FREP significantly increased serum cytokines, including IL-2, IL-8, IL-10, IL-12, IL-6, IL-1β, INF-γ, C-rection protein, and TNF-α, and promoted splenocyte proliferation in healthy mice. Finally, FREP could restore the counts of white blood cells, red blood cells, secretory immunoglobulin A, and antibody-forming cells and significantly promote the serum haemolysin level in mice treated with cyclophosphamide. The findings indicated that FREP possessed immunoregulatory activity in healthy mice and could improve the immune functions in immunosuppressive mice. Therefore, FREP could be exploited as an immunomodulatory agent and potential immunotherapeutic medicine for patients with inadequate immune function.

Research progress on the structural characterization, biological activity and product application of polysaccharides from Crataegus pinnatifida

Crataegus pinnatifida is a plant of the Crataegus genus in the Rosaceae family and is commonly used as a food and medicinal resource. Crataegus pinnatifida polysaccharide, as one of the main active ingredients of Crataegus pinnatifida, has a variety of beneficial biological activities, such as antioxidant, hypoglycemic activity, lipid-lowering, intestinal flora regulation, promotion immune regulation, and antitumor activities. However, the extraction methods of Crataegus pinnatifida polysaccharides lack innovation, the primary structure is relatively limited, and the biological activity mechanism needs to be further explored. Therefore, this review summarizes the research status of the extraction, purification, structural characterization, biological activity, and product application of Crataegus pinnatifida polysaccharides. The purpose of this study is to generate support for further development and application of polysaccharides from Crataegus pinnatifida.

Bee Pollen and Bread as a Super-Food: A Comparative Review of Their Metabolome Composition and Quality Assessment in the Context of Best Recovery Conditions

Recently, functional foods have been a subject of great interest in dietetics owing not only to their nutritional value but rather their myriad of health benefits. Moreover, an increase in consumers' demands for such valuable foods warrants the development in not only production but rather tools of quality and nutrient assessment. Bee products, viz., pollen (BP) and bread, are normally harvested from the flowering plants with the aid of bees. BP is further subjected to a fermentation process in bee hives to produce the more valuable and bioavailable BB. Owing to their nutritional and medicinal properties, bee products are considered as an important food supplements rich in macro-, micro-, and phytonutrients. Bee products are rich in carbohydrates, amino acids, vitamins, fatty acids, and minerals in addition to a myriad of phytonutrients such as phenolic compounds, anthocyanins, volatiles, and carotenoids. Moreover, unsaturated fatty acids (USFAs) of improved lipid profile such as linoleic, linolenic, and oleic were identified in BP and BB. This work aims to present a holistic overview of BP and BB in the context of their composition and analysis, and to highlight optimized extraction techniques to maximize their value and future applications in nutraceuticals.

Bee Pollen: Clinical Trials and Patent Applications

Bee pollen is a natural cocktail of floral nectar, flower pollen, enzymes, and salivary secretions produced by honeybees. Bee pollen is one of the bee products most enriched in proteins, polysaccharides, polyphenols, lipids, minerals, and vitamins. It has a significant health and medicinal impact and provides protection against many diseases, including diabetes, cancer, infectious, and cardiovascular. Bee pollen is commonly promoted as a cost-effective functional food. In particular, bee pollen has been applied in clinical trials for allergies and prostate illnesses, with a few investigations on cancer and skin problems. However, it is involved in several patents and health recipes to combat chronic health problems. This review aimed to highlight the clinical trials and patents involving bee pollen for different cases and to present the role of bee pollen as a supplementary food and a potential product in cosmetic applications.

New Insights into Potential Beneficial Effects of Bioactive Compounds of Bee Products in Boosting Immunity to Fight COVID-19 Pandemic: Focus on Zinc and Polyphenols

The coronavirus disease 2019 (COVID-19) is an epidemic caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Populations at risk as well as those who can develop serious complications are people with chronic diseases such as diabetes, hypertension, and the elderly. Severe symptoms of SARS-CoV-2 infection are associated with immune failure and dysfunction. The approach of strengthening immunity may be the right choice in order to save lives. This review aimed to provide an overview of current information revealing the importance of bee products in strengthening the immune system against COVID-19. We highlighted the immunomodulatory and the antiviral effects of zinc and polyphenols, which may actively contribute to improving symptoms and preventing complications caused by COVID-19 and can counteract viral infections. Thus, this review will pave the way for conducting advanced experimental research to evaluate zinc and polyphenols-rich bee products to prevent and reduce the severity of COVID-19 symptoms.

Botanical, Phytochemical, Anti-Microbial and Pharmaceutical Characteristics of Hawthorn (Crataegusmonogyna Jacq.), Rosaceae

Hawthorn (Crataegus monogyna Jacq.) is a wild edible fruit tree of the genus Crataegus, one of the most interesting genera of the Rosaceae family. This review is the first to consider, all together, the pharmaceutical, phytochemical, functional and therapeutic properties of C. monogyna based on numerous valuable secondary metabolites, including flavonoids, vitamin C, glycoside, anthocyanin, saponin, tannin and antioxidants. Previous reviews dealt with the properties of all species of the entire genera. We highlight the multi-therapeutic role that C. monogyna extracts could have in the treatment of different chronic and degenerative diseases, mainly focusing on flavonoids. In the first part of this comprehensive review, we describe the main botanical characteristics and summarize the studies which have been performed on the morphological and genetic characterization of the C. monogyna germplasm. In the second part, the key metabolites and their nutritional and pharmaceutical properties are described. This work could be an essential resource for promoting future therapeutic formulations based on this natural and potent bioactive plant extract.

The anti-hyperuricemic effects of green alga Enteromorpha prolifera polysaccharide via regulation of the uric acid transporters in vivo

A novel polysaccharide obtained from Enteromorpha prolifera (EPP) was purified through diethylaminoethyl cellulose-52 and Sephadex G-75 chromatography. Fourier transform infrared spectroscopy, high-performance liquid chromatography, and nuclear magnetic resonance (NMR) spectroscopy were employed to analyse the structure of EPP. It mainly comprised rhamnose, glucuronic acid, galactose, arabinose, and xylose at a molar ratio of 20.45:12.74:10.99:5.84:1.95, and its average molecular weight was 46.56 kDa. The seven major glycosidic residues identified by NMR were as follows: →2)-α-L-Araf-(1→, →2)-α-L-Rhap-(1→, →4)-α-L-Rhap-(1→, →2,6)-β-D-Galp-(1→, →4)-β-D-GlcpA-(1→, →3,4)-β-D-GlcpA-(1→, and →4)-β-Xylp-(1→. The effect of EPP on hyperuricemic mice was determined by analysing correlative general physical parameters, renal histopathology, renal gene expressions, and gut microbiome. EPP significantly reduced serum uric acid (UA), serum blood urea nitrogen, serum xanthine oxidase (XOD), and hepatic XOD as well as improved histological parameters in hyperuricemic mice. Furthermore, mRNA and protein expression analyses showed the upregulation of UA excretion genes such as ABCG2, OAT1, and NPT1 and downregulation of UA resorption gene URAT1. Moreover, EPP maintained the stability of the intestinal flora and confirmed that Parasutterella is closely related to the regulation of hyperuricemia. This study is the first to demonstrate the anti-hyperuricemic activity of EPP and highlight its therapeutic potential for hyperuricemia-related diseases.

Bee Pollen Polysaccharide From Rosa rugosa Thunb. (Rosaceae) Promotes Pancreatic β-Cell Proliferation and Insulin Secretion

Insufficient pancreatic β-cell or insulin-producing β-cell are implicated in all types of diabetes mellitus. Our previous studies showed bee pollen polysaccharide RBPP-P improves insulin resistance in type 2 diabetic mice by inhibiting liver fat deposition. However, its potential of regulating β-cell function and integrity is not fully known. Herein, we observed that β-cell proliferation (n = 10), insulin synthesis (n = 5, p = 0.01684) and insulin incretion (n = 5, p = 0.02115) were intensely activated in MIN6 cells when treatment with RBPP-P. In alloxan-induced diabetic mice, oral administration of RBPP-P (n = 10) effectively decreased the blood glucose (p = 0.0326), drink intake (p < 0.001) and urine (p < 0.001). It directly stimulated phosphorylation of p38 (p = 0.00439), ERK (p = 0.02951) and AKT (p = 0.0072) to maintain the islet function and mass. Thus, our data suggest that RBPP-P is a natural compound to regulate β-cell proliferation and function, indicating it might have therapeutic potential against type 1 diabetes.

Structural Characterization of an Alkali-Soluble Polysaccharide from Angelica sinensis and Its Antitumor Activity in Vivo

A novel alkali-soluble polysaccharide (AASP) was isolated from Angelica sinensis (Oliv.) Diels under aqueous alkali treatment, and its structural characterization and antitumor activity in Vivo were evaluated in present study. Results of HPGPC and IC revealed that AASP was a neutral polysaccharide containing Ara, Gal and Glc in the mole ratio of 1.00 : 2.26 : 24.43, with the average molecular weight of 4.7 kDa. Periodate oxidation, Smith degradation, methylation, FT-IR, and NMR analyses further demonstrated that a preliminary structure of AASP was proposed as follows: (1→3)-linked arabinose, (1→6)-linked galactose, and (1→), (1→4), (1→6), (1→3,6)-linked glucose with α- and β-configuration. In Vivo antitumor assays, AASP exhibited prominent antitumor effects on H22 hepatoma cells with an inhibitory ratio of 48.57 % and effectively protected thymuses and spleens of tumor-bearing mice. Besides, AASP displayed a proliferation stimulating activity of immunocytes (splenocytes, peritoneal macrophages and natural killer cells), and an auxo-action for cytokines release (TNF-α, IL-2 and IFN-γ), leading to the apoptosis of H22 solid tumors cells via G0/G1 phase arrested. The above data demonstrated that AASP holds great application potential to be a safe and effective antitumor supplement in the future.

A systems-based analysis to explore the multiple mechanisms of Shan Zha for treating human diseases

Shan Zha has garnered increasing attention in the field of functional foods and medicines due to its widely reported healing effects. However, the potential mechanisms of Shan Zha for human health benefits have not been fully interpreted. Therefore, in the current study, a systems-based method that integrates ADME evaluation, target fishing, gene ontology enrichment analysis, network pharmacology, and pathway analysis is proposed to clarify the underlying pharmacological mechanisms of Shan Zha. As a result, 45 active components of Shan Zha that interacted with 161 protein targets were screened and identified. Moreover, gene ontology enrichment, network and pathway analysis indicated that Shan Zha is beneficial for the treatment of cardiovascular system diseases, digestive system diseases, immune system diseases, inflammatory diseases, cancer, and other diseases through multiple mechanisms. Our study not only proposed an integrated method to comprehensively elucidate the complicated mechanisms of Shan Zha for the treatment of various disorders at the system level, but also provided a reference approach for the mechanistic research of other functional foods.

A Novel Optimization of Water-Soluble Compound Polysaccharides from Chinese Herbal Medicines by Quantitative Theory and Study on Its Characterization and Antioxidant Activities

The present study optimized the extraction characterization and antioxidant activities of water-soluble compound polysaccharides (CPs) from hawthorn, lotus leaf, Fagopyrum tataricum, semen cassiae, Lycium barbarum, and Poria cocos Chinese herbal medicines that have mass ratios of 4 : 2 : 2 : 1.5 : 1 : 1. The CPs yield equation was predicted using quantitative theory, to which a maximum CPs yield of 7.18±0.24 % under the following optimal extraction conditions: a water-to-raw material ratio of 30 mL/g, an extraction temperature of 65 °C, an extraction time of 45 min, and extraction mode ultrasonic-assistant extraction. CPs were consisted of Ara, Gal, Glc, Xyl, Man, GalA and GlcA in a molar ratio of 3.1 : 2.6 : 50.6 : 1.7 : 20.4 : 17.2 : 4.2. The HPGPC profiles and FT-IR spectra implied that CPs were heterogeneous acidic polysaccharides and possessed the β-d-pyranose configuration. Congo red test, CD spectrum and SEM revealed that CPs with three helix conformation showed a flocculent, granulous or sheet-like appearance. Furthermore, the relationships between antioxidant activity and concentration of CPs displayed significant positive correlation, and the scavenging abilities for DPPH, hydroxyl radical, ABTS, superoxide-anion radical and reducing power of CPs were 93.56±2.51 %, 84.03±1.69 %, 83.29±1.93 %, 37.49±1.93 % and 0.467±0.006 at a concentration of 4.0 mg/mL. Therefore, CPs could be applied as a potential natural antioxidant in pharmaceutical or functional food fields.

Chemical composition, antibacterial activity and action mechanism of different extracts from hawthorn (Crataegus pinnatifida Bge.)

Present study was designed to compared the total flavonoids and polyphenols contents and antibacterial activity of hawthorn extracts with different polarities as well as the underlying antibacterial mechanisms. The results showed that among all hawthorn extracts, methanol and ethanol extracts (ME and EE) exhibited high levels of total flavonoids and polyphenols contents, followed by acetone, ethyl acetate, trichloromethane and petroleum ether extracts. ME exhibited the strongest antibacterial activity against tested bacteria, especially Staphylococcus aureus with a 1.25 μg/mL of the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). Further analysis revealed that the main phenolic compounds from ME were epicatechin (281.6 mg/100 g DW), procyanidin B2 (243.5 mg/100 g DW), chlorogenic acid (84.2 mg/100 g DW) and quercetin (78.4 mg/100 g DW). The action mechanism of ME against S. aureus could be ascribed to ME damaging cell wall and cell membrane integrity, inhibiting intracellular enzyme activity, increasing reactive oxygen species (ROS), also changing expression of associated genes and then inducing apoptosis of S. aureus. In addition, the antimicrobial activity of ME against S. aureus has also been demonstrated to be efficient in the food matrix (whole milk).

Bioactive Constituents of F. esculentum Bee Pollen and Quantitative Analysis of Samples Collected from Seven Areas by HPLC

Bee pollen contains all the essential amino acids needed by humans. China is the largest producer of bee pollen in the world. In the present study, we identified 11 fatty acids in F. esculentum bee pollen oil by GC-MS analysis, and 16 compounds were isolated from F. esculentum bee pollen by column chromatography and identified. A high-performance liquid chromatography-diode array detector (HPLC-DAD) method was established for the quality control of F. esculentum bee pollen. A validated HPLC-DAD method was successfully applied to the simultaneous characterization and quantification of nine main constituents in seven samples collected from seven different areas in China. The results showed that all standard calibration curves exhibited good linearity (R2 > 0.999) in HPLC-DAD analysis with excellent precision, repeatability and stability. The total amount in the samples from the seven regions ranged from 23.50 to 46.05 mg/g. In addition, seven compounds were studied for their bioactivity using enzymic methods, whereby kaempferol (3) showed high α-glucosidase inhibitory activity (IC50: 80.35 μg/mL), ergosterol peroxide (8) showed high tyrosinase inhibitory activity (IC50: 202.37 μg/mL), and luteolin (1) had strong acetylcholinesterase inhibitory activity (IC50: 476.25 μg/mL). All results indicated that F. esculentum bee pollen could be a nutritious health food.

Simulated Digestion and Fermentation in Vitro by Human Gut Microbiota of Polysaccharides from Bee Collected Pollen of Chinese Wolfberry

Digestion and fermentation in vitro of polysaccharides from bee collected pollen of Chinese wolfberry (WBPPS) were investigated in the present study. It was found that WBPPS mainly consisted of mannose, ribose, rhamnose, galacturonic acid, glucose, galactose, xylose, and arabinose in a molar ratio of 0.38:0.09:0.17:0.64:0.22:0.67:0.08:1.03, respectively. WBPPS was not affected by human saliva. The fraction A (molecular weight 1340 kDa) of WBPPS was not broken down in simulated gastric and small intestinal juices, while the small fraction B (molecular weight 523 kDa) of WBPPS was degraded. Moreover, fermentation in vitro revealed that WBPPS could significantly enhance the production of short-chain fatty acids and modulate gut microbiota composition via increasing the relative abundances of genera Prevotella, Dialister, Megamonas, Faecalibacterium, and Alloprevotella and decreasing the numbers of genera Bacteroides, Clostridium XlVa, Parabacteroides, Escherichia/Shigella, Phascolarctobacterium, Parasutterella, Clostridium sensu stricto, and Fusobacterium.

Purification, Preliminary Characterization and Hepatoprotective Effects of Polysaccharides from Dandelion Root

In this study, purification, preliminary characterization and hepatoprotective effects of water-soluble polysaccharides from dandelion root (DRP) were investigated. Two polysaccharides, DRP1 and DRP2, were isolated from DRP. The two polysaccharides were α-type polysaccharides and didn't contain protein. DRP1, with a molecular weight of 5695 Da, was composed of glucose, galactose and arabinose, whereas DRP2, with molecular weight of 8882 Da, was composed of rhamnose, galacturonic acid, glucose, galactose and arabinose. The backbone of DRP1 was mainly composed of (1→6)-linked-α-d-Glc and (1→3,4)-linked-α-d-Glc. DRP2 was mainly composed of (1→)-linked-α-d-Ara and (1→)-linked-α-d-Glc. A proof-of-concept study was performed to assess the therapeutic potential of DRP1 and DRP2 in a mouse model that mimics acetaminophen (APAP) -induced liver injury (AILI) in humans. The present study shows DRP1 and DRP2 could protect the liver from APAP-induced hepatic injury by activating the Nrf2-Keap1 pathway. These conclusions demonstrate that the DRP1 and DRP2 might be suitable as functional foods and natural drugs in preventing APAP-induced liver injury.

Structure and immunomodulatory activity of a sulfated agarose with pyruvate and xylose substitutes from Polysiphonia senticulosa Harvey

A charged and size uniform polysaccharide PS2 was prepared from red seaweed Polysiphonia senticulosa Harvey. Based on nuclear magnetic resonance (NMR), fourier transform infrared (FTIR) spectroscopy, and electrospray ionization collision-induced-dissociation mass spectrometry (ESI-CID-MSⁿ) analysis, PS2 was determined to be a novel 6-O-sulfated agarose which was mainly composed of a repeating unit of alternating (1→3)-linked 6-sulfated-β-d-galactose and (1→4)-linked 3,6-anhydro-α-l-galactose in association with small amount of pyruvate substituted on galactose residues and xylose (Xyl) branched at C2 position of 3,6-anhydro-galactose. The immunomodulatory activity of PS2 was evaluated on RAW264.7 cells, and the results showed PS2 could increase nitric oxide (NO) production and enhanced the phagocytic activity of macrophages. Moreover, PS2 could significantly promote proliferation of T lymphocyte and potentiated the nature kill cell (NK) activity. These findings suggest that PS2 could be potentially developed as a novel valuable immunomodulator.

Pectic Bee Pollen Polysaccharide from Rosa rugosa Alleviates Diet-Induced Hepatic Steatosis and Insulin Resistance via Induction of AMPK/mTOR-Mediated Autophagy

Despite it is used as a nutraceutical against diabetes and obesity, the mechanism of action of bee pollen is still unclear. Pectic bee pollen polysaccharide (RBPP-P) was isolated from Rosa rugosa, and its structure was characterized by ¹³C-NMR and Fourier transform-infrared spectroscopy (FT-IR). Using high glucose and fatty acids-treated HepG2 cells and high fat diet (HFD)-induced obesity mice, we detected its effect on insulin function and lipid metabolism based on autophagy. RBPP-P contained arabinogalactan, rhamnogalacturonan I, and homogalacturonan domains. In vivo studies demonstrated that RBPP-P markedly ameliorated insulin resistance, glucose intolerance, and liver steatosis in obese mice. The suppressive effects of RBPP-P on liver steatosis and triglyceride content were mediated by increased autophagy and lipase expression in liver. In AMPK knockdown cells (prkaa 1/2^−/− MEF) and HFD-fed mice tissues (liver, gonadal white adipose, and inguinal white adipose), RBPP-P enhanced autophagy in AMPK/mTOR-dependent way in liver, but not in adipose tissue. These findings demonstrated that bee pollen polysaccharide alleviated liver steatosis and insulin resistance by promoting autophagy via an AMPK/mTOR-mediated signaling pathway, suggesting that RBPP-P could be a novel therapeutic agent used for the treatment of obesity and diabetes.

Bee pollen in allergy and immunology. Short review

Bee pollen is a natural resource - pollen collected by bees and stored in the beehive with various bee enzymes added as it is a mixture of plants pollen and bee saliva. It is rich source of various nutrients, among them exogenous amino acids. Therefore, it can be a good and natural dietary supplement. New possibilities for bee pollen usage arise every day, yet it can also be a threat. Although bee pollen can act as an immunostimulant and anti-allergic agent, it is also and maybe even primarily allergic or cross-reactive with many allergens. A number of bee pollen allergy cases was described worldwide. A caution is therefore needed before ingestion or any other form of administration, especially in case of children or individuals with atopic predispositions. Anti-allergic attributes and immunostimmulation ability still need further research.

Purification, characterization, and antitumor activity of a novel glucan from the fruiting bodies of Coriolus Versicolor

Cancer is one of the most common causes of deaths worldwide. Herein, we report an efficient natural anticancer glucan (CVG) extracted from Coriolus Versicolar (CV). CVG was extracted by the hot water extraction method followed by ethanol precipitation and purified using gas exclusion chromatography. Structural analysis revealed that CVG has a linear α-glucan chain composed of only (1→ 6)-α-D-Glcp. The antitumor activity of CVG on Sarcoma-180 cells was investigated in vitro and in vivo. Mice were treated with three doses of CVG (40, 100, 200 mg/kg body weight) for 9 days. Tumor weight, relative spleen, thymus weight, and lymphocyte proliferation were studied. A significant increase (P< 0.01) in relative spleen and thymus weight and a decrease (P< 0.01) in tumor weight at the doses of 100 and 200 mg/kg were observed. The results obtained demonstrate CVG has antitumor activity towards Sarcoma-180 cells by its immunomodulation activity.

Immunomodulatory activity of macromolecular polysaccharide isolated from Grifola frondosa

The present study was designed to evaluate the immune-modulating effects of the polysaccharide from Grifola frondosa (GFP) by using mouse peritoneal macrophage and cytoxan (CTX) induced immunosuppression models. Our results from the phagocytotic and mononuclear phagocytic system function assays showed that GFP-A (one component from GFP) stimulated the phagocytosis of the phagocytes. The splenocyte proliferation assay showed that GFP-A acted the effect combing ConA or LPS in splenocyte proliferation. The results showed that GFP-A increased indices of thymus and spleen, the levels of LDH and ACP in the spleen, the mRNA levels of IL-1β, IL-2, IL-6 and IFN-γ in splenocyte. And GFP-A also significantly increased the expression of CD4(+) and CD8(+) splenic T lymphocytes, which were suppressed by the CTX in peripheral blood. In conclusion, our results indicate that the GFP-A is involved in immunomodulatory effects leading to its modulatory effects on immunosuppression.

Inhibitory effect on HT-29 colon cancer cells of a water-soluble polysaccharide obtained from highland barley

A water-soluble polysaccharide (BP-1) was obtained from highland barley (Hordeum vulgare L.) by hot water extraction and purification of sepharose column chromatography. BP-1 had an average molecular weight of about 6.7×10⁴Da and was composed of glucose (Glc), xylose (Xyl), arabinose (Ara) and rhamnose (Rha) with a relative molar ratio of 8.82:1.92:1.50:1.00. It was found that BP-1 inhibited proliferation of human colon cancer cells (HT-29) in a time- and dose-dependent manner with half maximal inhibitory concentration at 48h of 48.18μg/mL. Western blotting results showed that BP-1 enhanced the phosphorylation of c-Jun N-terminal kinase (JNK), processes associated with the reactive oxygen species (ROS) formation and inhibited nuclear factor-κB (NF-κB) translocation from cytoplasm into nucleus. Meanwhile, the BP-1-induced apoptosis was related to the regulation of apoptosis-associated proteins, such as B-cell lymphoma-2 (Bcl-2), release of cytochrome C from mitochondria to cytoplasm and activation of caspase-8 and caspase-9. These results suggest that BP-1-induced HT-29 apoptosis through ROS-JNK and NF-κB-mediated caspase pathways.

Experimental Studies on Some Immunotoxicological Aspects of Aflatoxins Containing Diet and Protective Effect of Bee Pollen Dietary Supplement

Aflatoxins (AFs), widely distributed food-borne mycotoxins, affect quality and safety of food and cause economic losses in livestock. In this study, the protective effect of Bee Pollen (BP) against some immunotoxic hazards elucidated from eating of AFs-containing diet was investigated in Wistar rats. Rats were randomly classified intofour groups and treated for 30 days, Group 1; control negative, Group 2; Total AFs (3 mg kg(-1) basal diet), Group 3; BP (20 g kg(-1) basal diet) and Group 4; AFs+BP in basal diet. The immunoprotective effect of BP was revealed in terms of increasing (relative to levels seen in Group 2 rats that consumed the AFs diet) serum total protein and globulin levels, restored normal neutrophil (PMN)/lymphocyte ratio, increased PMN phagocytic activity and increased lymphocyte proliferative capacity. Also, the use of the BP reduced spleen H2O2 levels and increased GSH content while maintaining normal levels of NO formation. Histopathologic analysis showed thatthe AFs caused lymphocytic depletion in the spleen; however, BP induced lymphocytic hyperplasia and reduced the levels of AFs-inducible cellular exhaustion or depletion. These results provide evidence of a protective effect of BP against some immunotoxic actions induced in situ by consumption of AFs.

Immunomodulatory potencies of isolated compounds from Crataegus azarolus through their antioxidant activities

The search of natural immunomodulatory agents has become an area of great interest in order to reduce damage to the human body. In this study, the immunomodulatory potential of Crataegus azarolus and its isolated hyperoside on mouse lymphocytes and macrophages in vitro was assessed. The effect of C. azarolus natural compounds on splenocytes proliferation, natural killer (NK) and cytotoxic T lymphocytes (CTL) activities, and on macrophage-mediated cytotoxicity were assessed by MTT test. Phagocytic activity and inhibition of nitric oxide (NO) release by macrophages were also evaluated. The antioxidant capacity of these products was evaluated by determining their cellular antioxidant activity (CAA) in splenocytes and macrophages. Depending on the concentrations, both ethyl acetate (EA) extract and hyperoside (Hyp) from C. azarolus affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide release. Whereas, the above-mentioned products significantly promote LPS and lectin-stimulated splenocyte proliferation, implying a potential activation of lymphocytes B and T enhancing humoral and cellular immune responses. Moreover, EA extract and Hyp could enhance the activity of NK and T lymphocytes cells, as well as the macrophages-mediated cytotoxicity against B16F10 cells. The anti-inflammatory activity was concomitant with the cellular antioxidant effect of the tested compounds against macrophages and splenocytes. Collectively, C. azarolus and its isolated hyperoside exhibited an immunomodulatory effect through their antioxidant activity. These findings suggest that C. azarolus should be explored as a novel potential immunomodulatory agent for the treatment of inflammatory diseases.

Polyphenols from Bee Pollen: Structure, Absorption, Metabolism and Biological Activity

Bee pollen constitutes a natural source of antioxidants such as phenolic acids and flavonoids, which are responsible for its biological activity. Research has indicated the correlation between dietary polyphenols and cardioprotective, hepatoprotective, anti-inflammatory, antibacterial, anticancerogenic, immunostimulating, antianaemic effects, as well as their beneficial influence on osseous tissue. The beneficial effects of bee pollen on health result from the presence of phenolic acids and flavonoids which possess anti-inflammatory properties, phytosterol and linolenic acid which play an anticancerogenic role, and polysaccharides which stimulate immunological activity. Polyphenols are absorbed in the alimentary tract, metabolised by CYP450 enzymes, and excreted with urine and faeces. Flavonoids and phenolic acids are characterised by high antioxidative potential, which is closely related to their chemical structure. The high antioxidant potential of phenolic acids is due to the presence and location of hydroxyl groups, a carboxyl group in the immediate vicinity of ortho-diphenolic substituents, and the ethylene group between the phenyl ring and the carboxyl group. As regards flavonoids, essential structural elements are hydroxyl groups at the C5 and C7 positions in the A ring, and at the C3′ and C4′ positions in the B ring, and a hydroxyl group at the C3 position in the C ring. Furthermore, both, the double bond between C2 and C3, and a ketone group at the C4 position in the C ring enhance the antioxidative potential of these compounds. Polyphenols have an ideal chemical structure for scavenging free radicals and for creating chelates with metal ions, which makes them effective antioxidants in vivo.

Purification and characterization of a novel polysaccharide-peptide complex from Clinacanthus nutans Lindau leaves

A novel polysaccharide-peptide complex CNP-1-2 with molecular weight of 9.17 × 10(4) Da was obtained from Clinacanthus nutans Lindau leaves by hot water extraction, ethanol precipitation, and purification with Superdex 200 and DEAE-Sepharose Fast Flow column chromatography. CNP-1-2 exhibited the highest growth inhibitory effect on human gastric cancer cells SGC-7901 with inhibition ratio of 92.34% and stimulated activation of macrophages with NO secretion level of 47.53 μmol/L among the polysaccharide fractions. CNP-1-2 comprised approximately 87.25% carbohydrate and 9.37% protein. Monosaccharide analysis suggested that CNP-1-2 was composed of L-rhamnose, l-arabinose, D-mannose, D-glucose and D-galactose with a molar ratio of 1.30:1.00:2.56:4.95:5.09. Methylation analysis, FT-IR, and (1)H NMR spectroscopy analysis revealed that CNP-1-2 might have a backbone consisting of 1,4-linked Glcp, 1,3-linked Glcp, 1,3-linked Manp, 1,4-linked Galp, 1,2,6-linked Galp and 1,2,6-linked Galp. Its side chain might be composed of 1-linked Araf, 1,6-linked Galp and 1-linked Rhap residues. AFM (atomic force micrograph) analysis revealed that CNP-1-2 had the molecular aggregation along with branched and entangled structure.

Effect of sonication on different quality parameters of Pinus massoniana pollen

A study was initiated with the objective of evaluating the effects of sonication treatment on important quality parameters of extract of Pinus massoniana pollen. Sonication of extract was done (frequency 20kHz and various amplitude levels) for 10, 30, 50min, respectively. As results, total polysaccharide, phenolics and flavonoids significantly increased (P<0.05). And sonicated P.massoniana pollen displays strong immuno-stimulating activity by increasing proliferations of splenic lymphocytes and subsets of CD4+ T cells (CD3+CD4+), CD8 T cells (CD3+CD8+), and increased Ig secretion. Sonicated P. massoniana pollen also showed anti-tumor function by inhibition of tumor cell proliferation, inhibition of ROS production, up-regulation of GSH/GSSG ration, up-regulating the gene expression of P53, Bax and down-regulating the gene expression of Bcl-2. Findings of the present study suggested the sonication treatment of P. massoniana pollen could improve the quality and bioactivity of P. massoniana pollen, indicating that sonication is effective in processing of pollen and could be a potential process in tumor prevention and treatment.

Effects of supplementary bee pollen and its polysaccharides on nutrient digestibility and serum biochemical parameters in Holstein calves

This study investigated the effects of supplementing the diets of 14–70-day calves with dietary bee pollen (BP) or its polysaccharides (PS) on growth performance, serum biochemical parameters, and apparent nutrient digestibility. Twenty-five newborn Holstein female calves were randomly offered one of the five diets (five calves per diet): a milk replacer supplemented with 0 (Control), 10 (10BP), 25 (25BP), or 50 g/day (50BP) bee pollen, or 5 g/day (5PS) bee pollen polysaccharides. The trial lasted 56 days, during which growth performance, apparent nutrient digestibility, and serum biochemical parameters were measured. Calves fed diets with BP had a greater bodyweight gain. Supplementation with BP or PS had significant effects on the apparent digestibility of DM, Ca and P in calves (P = 0.025, 0.012, and 0.076, respectively). The apparent DM digestibility of calves from group 25BP or 5PS was increased by 9.7% or 8.2% (P = 0.007 or 0.019), respectively, compared with that in the Control group. No significant differences were observed in serum concentrations of alkaline phosphatase, urea nitrogen, glucose, total protein, albumin, total cholesterol and triglycerides. These results demonstrated that dietary supplementation of BP at 25 g/day·calf or PS at 5 g/day·calf improved nutrient digestibility in pre-ruminant calves.

Polysaccharides from Cymbopogon citratus with antitumor and immunomodulatory activity

Abstract Context: Most of the present studies on the antitumor efficiency of Cymbopogon citratus (DC.) Stapf (Gramineae) are limited to its low-mass compounds, and little information about the antitumor activity of polysaccharides from this plant is available.

OBJECTIVES

This study focused on the potential antitumor and immunomodulatory activities of polysaccharides (CCPS) from C. citratus.

MATERIALS AND METHODS

CCPS was isolated using the water extraction-ethanol precipitation method. The sarcoma 180 (S180) cells-inoculated mice were intraperitoneally administrated with CCPS (30-200 mg/kg/d) for seven consecutive days. The effects of CCPS on tumor growth, thymus and spleen weights, splenocyte proliferation, and cytokine secretion in the tumor-bearing mice were measured. The cytotoxicity of CCPS (50-800 μg/mL) towards S180 cells was also studied.

RESULTS

CCPS significantly inhibited the growth of the transplanted S180 tumors, with the inhibition rates ranging from 14.8 to 37.8%. Simultaneously, CCPS dose-dependently improved the immunity of the tumor-bearing mice. With the highest dose of 200 mg/kg/d, the thymus and spleen indices were increased by 21.9 and 91.9%, respectively; ConA- and LSP-induced splenocyte proliferations were increased by 32.7 and 35.3%, respectively. The secretions of interleukin 2 (IL-2), interleukin 6 (IL-6), interleukin 2 (IL-12), and tumor necrosis factor-α (TNF-α) were increased by 103.2, 40.2, 23.6, and 26.3%, respectively. Nevertheless, almost no toxicity of CCPS towards S180 cells was observed, with the maximal inhibition rate less than 15% at the CCPS concentration of 800 μg/mL.

CONCLUSION

CCPS exhibited antitumor activity in vivo, and this activity might be achieved by immunoenhancement rather than direct cytotoxicity.

Schisandra polysaccharide evokes immunomodulatory activity through TLR 4-mediated activation of macrophages

Schisandra chinensis (Turcz.) Baill has been used in traditional Chinese medicine for centuries. Previous studies have shown that Schisandra polysaccharide (SCPP11) has robust antitumor activity in vivo. In this study, the immunomodulatory activity and mechanisms of action of SCPP11 were investigated further to reveal its mechanism of action against tumors. Results showed that SCPP11 increased the thymus and spleen indices, pinocytic activity of peritoneal macrophages, and hemolysin formation in CTX-induced immunosuppressed mice. Moreover, SCPP11 significantly increased immunoglobulin levels, cytokines levels in vivo and induced RAW264.7 cells to secrete cytokines in vitro. RAW264.7 cells pretreated with SCPP11 significantly inhibited the proliferation of HepG-2 cells. In addition, SCPP11 promoted both the expression of iNOS protein and of iNOS and TNF-α mRNA. TLR-4 is a possible receptor for SCPP11-mediated macrophage activation. Therefore, the data suggest that SCPP11 exerted its antitumor activity by improving immune system functions through TLR-4-mediated up-regulation of NO and TNF-α.