Effects of selenylation modification on immune-enhancing activity of garlic polysaccharide

Recent advances in dietary polysaccharides from Allium species: Preparation, characterization, and bioactivity

Allium plants, including garlic, onions, shallots, and leeks, belong to the Alliaceae family and are utilized as vegetable, medicinal, and ornamental plants. These plants are consumed both raw and cooked and are noted in traditional medicine for their antibacterial, antitumor, and diuretic properties. Allium plants are a rich source of polyphenols, organosulfur compounds, flavonoids, alkaloids, and polysaccharides, which contribute to their health benefits. As consumer interest in the association between diet and health grows, there is an increasing market demand for foods that promote health, particularly those rich in dietary fiber or non-starch polysaccharides. Allium polysaccharides (APS) have molecular weights of 1 × 103-1 × 106 Da containing small amounts of pectin, glucofructan, or glycoproteins and large amounts of fructans. APS, despite its complex structure, is one of the principal active components of Allium plants but is often overlooked, which restricts its practical application. This paper provides a comprehensive overview of the extraction and purification, structural and functional characteristics, bioactivities, structure-function relationships, and chemical modifications of APS, as well as the effects of APS processing and storage. Additionally, this paper outlines future research directions for APS, which will inform its development and application in the food, pharmaceutical, and cosmetic industries.

Enhanced uranium sequestration through selenite-modified nano-chitosan loaded with melatonin: Facilitating U(IV) conversion

The combined chemotoxicity and radiotoxicity associated with uranium, utilized in nuclear industry and military applications, poses significant threats to human health. Among uranium pollutants, uranyl is particularly concerning due to its high absorptivity and potent nephrotoxicity in its + 6 valence state. Here, we have serendipitously found Na2SeO3 facilitates the conversion of U(VI) to U(IV) precipitates. A novel approach involving nano-chitosan loaded internally with melatonin and externally modified with selenite (NPs Cs-Se/MEL) was introduced. This modification not only enhances the conversion of U(VI) to U(IV) but also preserves the spherical nanostructure and specific surface area, leading to increased adsorption of U(VI) compared to unmodified samples. Selenite modification improves lysosomal delivery in HEK-293 T cells and kidney distribution of the nanoparticles. Furthermore, NPs Cs-Se/MEL demonstrated a heightened uranium concentration in urine and exhibited remarkable efficiency in uranium removal, resulting in a reduction of uranium deposition in serum, kidneys, and femurs by up to 52.02 %, 46.79 %, and 71.04 %, respectively. Importantly, NPs Cs-Se/MEL can be excreted directly from the kidneys into urine when carrying uranium. The results presented a novel mechanism for uranium adsorption, making selenium-containing nano-materials attractive for uranium sequestration and detoxification.

Chemically modified seaweed polysaccharides: Improved functional and biological properties and prospective in food applications

Seaweed polysaccharides are natural biomacromolecules with unique physicochemical properties (e.g., good gelling, emulsifying, and film-forming properties) and diverse biological activities (e.g., anticoagulant, antioxidant, immunoregulatory, and antitumor effects). Furthermore, they are nontoxic, biocompatible and biodegradable, and abundant in resources. Therefore, they have been widely utilized in food, cosmetics, and pharmaceutical industries. However, their properties and bioactivities sometimes are not satisfactory for some purposes. Modification of polysaccharides can impart the amphiphilicity and new functions to the biopolymers and change the structure and conformation, thus effectively improving their functional properties and biological activities so as to meet the requirement for targeted applications. This review outlined the modification methods of representative red algae polysaccharides (carrageenan and agar), brown algae polysaccharides (fucoidan, alginate, and laminaran), and green algae polysaccharides (ulvan) that have potential food applications, including etherification, esterification, degradation, sulfation, phosphorylation, selenylation, and so on. The improved functional properties and bioactivities of the modified seaweed polysaccharides and their potential food applications are also summarized.

Garlic bioactive substances and their therapeutic applications for improving human health: a comprehensive review

Garlic (Allium sativum L.) is a widely abundant spice, known for its aroma and pungent flavor. It contains several bioactive compounds and offers a wide range of health benefits to humans, including those pertaining to nutrition, physiology, and medicine. Therefore, garlic is considered as one of the most effective disease-preventive diets. Many in vitro and in vivo studies have reported the sulfur-containing compounds, allicin and ajoene, for their effective anticancer, anti-diabetic, anti-inflammatory, antioxidant, antimicrobial, immune-boosting, and cardioprotective properties. As a rich natural source of bioactive compounds, including polysaccharides, saponins, tannins, linalool, geraniol, phellandrene, β-phellandrene, ajoene, alliin, S-allyl-mercapto cysteine, and β-phellandrene, garlic has many therapeutic applications and may play a role in drug development against various human diseases. In the current review, garlic and its major bioactive components along with their biological function and mechanisms of action for their role in disease prevention and therapy are discussed.

Extraction, purification, structural features, modifications, bioactivities, structure-activity relationships, and applications of polysaccharides from garlic: A review

Garlic is a common vegetable and spice in people's daily diets, in which garlic polysaccharide (GP) is one of the most important active components with a variety of benefits, such as antioxidant, immune-enhancing, anti-inflammatory, liver-protective and bowel-regulating properties. >20 types of GPs, mainly crude polysaccharides, have been identified. However, the exact chemical composition of GPs or the mechanism underlying their pharmacological activity is still not fully understood. The extraction and purification methods of GPs are compared in this review while providing detailed information on their structural features, identification methods, major biological activities, mechanisms of actions, structural modifications, structure-activity relationships as well as potential applications. Finally, the limitations of GP research and future issues that need to be addressed are discussed in this review. GPs are widely recognized as substances with great potential in the pharmaceutical and food industries. Therefore, this review aims to provide a comprehensive summary of the latest research progresses in the field of GPs, together with scientific insights and a theoretical support for the development of GPs in research and industrialization.

Health-promoting foods and food crops of West-Africa origin: The bioactive compounds and immunomodulating potential

The rural communities of the sub-Sahara regions in Africa are rich in diverse indigenous culinary knowledge and foods, food crops, and condiments such as roots/tubers, cereal, legumes/pulses, locust beans, and green leafy vegetables. These food crops are rich in micronutrients and phytochemicals, which have the potentials to address hidden hunger as well as promote health when consumed. Some examples of these are fermented foods such as ogi and plants such as Vernonia amygdalina (bitter leaf), Zingiber officinales (garlic), Hibiscus sabdariffa (Roselle), and condiments. Food crops from West Africa contain numerous bioactive substances such as saponins, alkaloids, tannins, phenolics, flavonoids, and monoterpenoid chemicals among others. These bioresources have proven biological and pharmacological activities due to diverse mechanisms of action such as immunomodulatory, anti-inflammatory, antipyretic, and antioxidant activities which made them suitable as candidates for nutraceuticals and pharma foods. This review seeks to explore the different processes such as fermentation applied during food preparation and food crops of West-African origin with health-promoting benefits. The different bioactive compounds present in such food or food crops are discussed extensively as well as the diverse application, especially regarding respiratory diseases. PRACTICAL APPLICATIONS: The plants and herbs summarized here are more easily accessible and affordable by therapists and others having a passion for promising medicinal properties of African-origin plants.The mechanisms and unique metabolic potentials of African food crops discussed in this article will promote their applicability as a template molecule for novel drug discoveries in treatment strategies for emerging diseases. This compilation of antiviral plants will help clinicians and researchers bring new preventive strategies in combating COVID-19 like viral diseases, ultimately saving millions of affected people.

Chemical Modification, Characterization, and Activity Changes of Land Plant Polysaccharides: A Review

Plant polysaccharides are widely found in nature and have a variety of biological activities, including immunomodulatory, antioxidative, and antitumoral. Due to their low toxicity and easy absorption, they are widely used in the health food and pharmaceutical industries. However, low activity hinders the wide application. Chemical modification is an important method to improve plant polysaccharides' physical and chemical properties. Through chemical modification, the antioxidant and immunomodulatory abilities of polysaccharides were significantly improved. Some polysaccharides with poor water solubility also significantly improved their water solubility after modification. Chemical modification of plant polysaccharides has become an important research direction. Research on the modification of plant polysaccharides is currently increasing, but a review of the various modification studies is absent. This paper reviews the research progress of chemical modification (sulfation, phosphorylation, acetylation, selenization, and carboxymethylation modification) of land plant polysaccharides (excluding marine plant polysaccharides and fungi plant polysaccharides) during the period of January 2012-June 2022, including the preparation, characterization, and biological activity of modified polysaccharides. This study will provide a basis for the deep application of land plant polysaccharides in food, nutraceuticals, and pharmaceuticals.

Onion and garlic polysaccharides: A review on extraction, characterization, bioactivity, and modifications

Allium cepa (onion) and Allium sativum (garlic) are important members of the Amaryllidaceae (Alliaceae) family and are being used both as food and medicine for centuries in different parts of the world. Polysaccharides have been extracted from different parts of onion and garlic such as bulb, straw and cell wall. The current literature portrays several studies on the extraction of polysaccharides from onion and garlic, their modification and determination of their structural (molecular weight, monosaccharide unit and their arrangement, type and position of glycosidic bond or linkage, degree of polymerization, chain conformation) and functional properties (emulsifying property, moisture retention, hygroscopicity, thermal stability, foaming ability, fat-binding capacity). In this line, this review, summarizes the various extraction techniques used for polysaccharides from onion and garlic, involving methods like solvent extraction method. Furthermore, the antioxidant, antitumor, anticancer, immunomodulatory, antimicrobial, anti-inflammatory, and antidiabetic properties of onion and garlic polysaccharides as reported in in vivo and in vitro studies is also critically assessed in this review. Different studies have proved onion and garlic polysaccharides as potential antioxidant and immunomodulatory agent. Studies have implemented to improve the functionality of onion and garlic polysaccharides through various modification approaches. Further studies are warranted for utilizing onion and garlic polysaccharides in the food, nutraceutical, pharmaceutical and cosmetic industries.

Effect of different ionic liquids and organic solvents on the structural and physicochemical properties of cellulose-protein complexes extracted from Se-enriched peanut leaves

Abundant cellulose and insoluble protein were contained in the Se-enriched peanut leaf residue, a by-product from leaf protein extraction. Ionic liquids (ILs) were used to extract the cellulose-protein complexes (CPCs) from Se-enriched peanut leaf residue. The effects of various ILs as extractants and organic solvents as regenerant on the physicochemical properties of CPCs were compared. The results showed that the yield of CPCs and recovery yield of [AMIM]Cl (1-allyl-3-methylimidazole chloride) were better than those of [BMIM]Cl (1-butyl-3-methylimidazolium chloride). Simultaneously, it could be seen from the infrared absorption peaks and secondary structure fitting results that [BMIM]Cl seemed stronger than [AMIM]Cl in destroying the secondary structure of CPCs. Scanning electron microscope (SEM) showed that the CPCs extracted by [BMIM]Cl were lamellate with holes on the surface, and the CPCs extracted by [AMIM]Cl were rough, almost without holes on the surface. Furthermore, the transmittance and tensile strength of the film which contained BA-CPC ([BMIM]Cl as extractant and acetonitrile as regenerant) film were better than those contained AA-CPC ([AMIM]Cl as extractant and acetonitrile as regenerant) film, which might be mainly because the types of ILs and regenerants affect the particle size of CPCs, thereby influencing the mechanical properties of the film.

Seaweed polysaccharides: Emerging extraction technologies, chemical modifications and bioactive properties

Nowadays, consumers are increasingly aware of the relationship between diet and health, showing a greater preference of products from natural origin. In the last decade, seaweeds have outlined as one of the natural sources with more potential to obtain bioactive carbohydrates. Numerous seaweed polysaccharides have aroused the interest of the scientific community, due to their biological activities and their high potential on biomedical, functional food and technological applications. To obtain polysaccharides from seaweeds, it is necessary to find methodologies that improve both yield and quality and that they are profitable. Nowadays, environmentally friendly extraction technologies are a viable alternative to conventional methods for obtaining these products, providing several advantages like reduced number of solvents, energy and time. On the other hand, chemical modification of their structure is a useful approach to improve their solubility and biological properties, and thus enhance the extent of their potential applications since some uses of polysaccharides are still limited. The present review aimed to compile current information about the most relevant seaweed polysaccharides, available extraction and modification methods, as well as a summary of their biological activities, to evaluate knowledge gaps and future trends for the industrial applications of these compounds.Key teaching pointsStructure and biological functions of main seaweed polysaccharides.Emerging extraction methods for sulfate polysaccharides.Chemical modification of seaweeds polysaccharides.Potential industrial applications of seaweed polysaccharides.Biological activities, knowledge gaps and future trends of seaweed polysaccharides.

Medicinal plants in mitigating electromagnetic radiation-induced neuronal damage: a concise review

Although the evidence is inconclusive, epidemiological studies strongly suggest that increased exposure to electromagnetic radiation (EMR) increases the risk of brain tumors, parotid gland tumors, and seminoma. The International Agency for Research on Cancer (IARC) has classified mobile phone radiofrequency radiation as possibly carcinogenic to humans (Group 2B). Humans being are inadvertently being exposed to EMR as its prevalence increases, mainly through mobile phones. Radiation exposure is unavoidable in the current context, with mobile phones being an inevitable necessity. Prudent usage of medicinal plants with a long history of mention in traditional and folklore medicine and, more importantly, are safe, inexpensive, and easily acceptable for long-term human use would be an appealing and viable option for mitigating the deleterious effects of EMR. Plants with free radical scavenging, anti-oxidant and immunomodulatory properties are beneficial in maintaining salubrious health. Green tea polyphenols, Ginkgo biloba, lotus seedpod procyanidins, garlic extract, Loranthus longiflorus, Curcuma amada, and Rosmarinus officinalis have all been shown to confer neuroprotective effects in validated experimental models of study. The purpose of this review is to compile for the first time the protective effects of these plants against mobile phone-induced neuronal damage, as well as to highlight the various mechanisms of action that are elicited to invoke the beneficial effects.

Selenium-Containing Polysaccharides—Structural Diversity, Biosynthesis, Chemical Modifications and Biological Activity

Selenosugars are a group of sugar derivatives of great structural diversity (e.g., molar masses, selenium oxidation state, and selenium binding), obtained as a result of biosynthesis, chemical modification of natural compounds, or chemical synthesis. Seleno-monosaccharides and disaccharides are known to be non-toxic products of the natural metabolism of selenium compounds in mammals. In the case of the selenium-containing polysaccharides of natural origin, their formation is also postulated as a form of detoxification of excess selenium in microorganisms, mushroom, and plants. The valency of selenium in selenium-containing polysaccharides can be: 0 (encapsulated nano-selenium), IV (selenites of polysaccharides), or II (selenoglycosides or selenium built into the sugar ring to replace oxygen). The great interest in Se-polysaccharides results from the expected synergy between selenium and polysaccharides. Several plant- and mushroom-derived polysaccharides are potent macromolecules with antitumor, immunomodulatory, antioxidant, and other biological properties. Selenium, a trace element of fundamental importance to human health, has been shown to possess several analogous functions. The mechanism by which selenium exerts anticancer and immunomodulatory activity differs from that of polysaccharide fractions, but a similar pharmacological effect suggests a possible synergy of these two agents. Various functions of Se-polysaccharides have been explored, including antitumor, immune-enhancement, antioxidant, antidiabetic, anti-inflammatory, hepatoprotective, and neuroprotective activities. Due to being non-toxic or much less toxic than inorganic selenium compounds, Se-polysaccharides are potential dietary supplements that could be used, e.g., in chemoprevention.

The characterization of optimal selenized garlic polysaccharides and its immune and antioxidant activity in chickens

The purpose of this study was to optimize modification conditions of selenized garlic polysaccharides (sGPS) and investigate its structural characterization, immune and antioxidant activities. Herein, selenized garlic polysaccharides (sGPS) were prepared using by HNO₃-Na₂SeO₃ selenylation method. And then modification conditions of sGPS were optimized through L₉ (3⁴) orthogonal test. The structural characterization of sGPS were identified by the Fourier-transform infrared (FT-IR), Solid-State nuclear magnetic resonance (NMR) spectra, X-ray diffraction (XRD) and thermogravimetric (TGA). The morphology of sGPS was detected using scanning electron microscope (SEM) and transmission electron microscope (TEM). In vivo investigation showed that sGPS significantly improved serum hemagglutination-inhibition (HI) antibody titers against Newcastle disease virus, enhanced secretory IgA (sIgA), IFN-γ, IL-2 secretion in jejunum and trachea irrigation compared with vaccine immunized control group. Furthermore, it showed that sGPS had some effects on the antioxidant activities in livers of chickens. In conclusion, the optimal modification conditions of sGPS were as follows: reaction temperature was 70 °C, the dosage of Na₂SeO₃ was 400 mg and reaction time was 6 h. The selenylation modification of garlic polysaccharides (GPS) could improve its immune and antioxidant activity in chickens.

Content and composition analysis of polysaccharides from Blaps rynchopetera and its macrophage phagocytic activity

Blaps rynchopetera Fairmaire has a long history of use as a folk medicine in China for treating fever, cough, gastritis, boils, and tumors. In the present study, the content analyses, monosaccharide composition analyses, and the macrophage phagocytic activity of rynchopetera polysaccharides (RPS) were reported. B. rhynchoptera is rich in polysaccharides (content value 3.97%). Through PMP (1-phenyl-3-methyl-5-pyrazolone) pre-column derivatization and high performance liquid chromatography (HPLC) testing, the results showed that RPS consist of 8 known monosaccharides, including D-mannose (Man), Rhamnose (Rha), D-glucuronic acid (GlcUA), D-galacturonic acid (GalUA), D-glucose (Glc), D-galactose (Gal), Arabinose (Ara), and Fucose (Fuc), with the total content of 171.70 mg g−1 and Glc has the highest content of 45.40 mg g−1. The phagocytic ability of mouse peritoneal macrophages was investigated after RPS stimulating alone and combined with lipopolysaccharide (LPS). RPS played an important role in the engulfment of mouse peritoneal macrophages and can significantly enhance the phagocytic ability of macrophages. However, no synergistic effects were observed when RPS combined with LPS.

Research progress on the biological activities of selenium polysaccharides

Selenium polysaccharides, an important organic selenium product, possess better antioxidant, antitumour, immune regulation, hypoglycaemic, and heavy metal removal activities than that of either polysaccharides or inorganic selenium.

Bioactive Compounds and Biological Functions of Garlic (Allium sativum L.)

Garlic (Allium sativum L.) is a widely consumed spice in the world. Garlic contains diverse bioactive compounds, such as allicin, alliin, diallyl sulfide, diallyl disulfide, diallyl trisulfide, ajoene, and S-allyl-cysteine. Substantial studies have shown that garlic and its bioactive constituents exhibit antioxidant, anti-inflammatory, antibacterial, antifungal, immunomodulatory, cardiovascular protective, anticancer, hepatoprotective, digestive system protective, anti-diabetic, anti-obesity, neuroprotective, and renal protective properties. In this review, the main bioactive compounds and important biological functions of garlic are summarized, highlighting and discussing the relevant mechanisms of actions. Overall, garlic is an excellent natural source of bioactive sulfur-containing compounds and has promising applications in the development of functional foods or nutraceuticals for the prevention and management of certain diseases.

Bioactive Compounds and Biological Functions of Garlic (Allium sativum L.)

Garlic (Allium sativum L.) is a widely consumed spice in the world. Garlic contains diverse bioactive compounds, such as allicin, alliin, diallyl sulfide, diallyl disulfide, diallyl trisulfide, ajoene, and S-allyl-cysteine. Substantial studies have shown that garlic and its bioactive constituents exhibit antioxidant, anti-inflammatory, antibacterial, antifungal, immunomodulatory, cardiovascular protective, anticancer, hepatoprotective, digestive system protective, anti-diabetic, anti-obesity, neuroprotective, and renal protective properties. In this review, the main bioactive compounds and important biological functions of garlic are summarized, highlighting and discussing the relevant mechanisms of actions. Overall, garlic is an excellent natural source of bioactive sulfur-containing compounds and has promising applications in the development of functional foods or nutraceuticals for the prevention and management of certain diseases.

Phosphorylated Radix Cyathulae officinalis Polysaccharides Act as Adjuvant via Promoting Dendritic Cell Maturation

The aim of this study was to investigate whether phosphorylated Radix Cyathulae officinalis Kuan polysaccharides (pRCPS) used as adjuvant with foot-and-mouth disease vaccine (FMDV) can stimulate specific humoral and cellular immune responses in ICR mice. The results demonstrated that pRCPS significantly up-regulated FMDV-specific IgG, IgG1, IgG2b and IgG2a antibody levels and splenocyte proliferation. pRCPS also promoted the killing activities of cytotoxic T lymphocytes (CTL) and natural killer cells (NK). In addition, pRCPS enhanced the expression levels of IL-2, IL-4, and IFN-γ in CD4⁺ T cells and the level of IFN-γ in CD8⁺ T cells. Importantly, pRCPS enhanced the expression of MHCII, CD40⁺, CD86⁺, and CD80⁺ in dendritic cells (DCs). This study indicated that phosphorylation modification could increase immune-enhancing activities of RCPS, and pRCPS could promote humoral and cellular immune responses through facilitating DC maturation.

The Selenylation Modification of Epimedium Polysaccharide and Isatis Root Polysaccharide and the Immune-enhancing Activity Comparison of Their Modifiers

Epimedium polysaccharide (EPS) and isatis root polysaccharide (IRPS) were extracted, purified, and selenizingly modified by nitric acid-sodium selenite method to obtain nine selenizing EPSs (sEPSs), sEPS1-sEPS9 and nine selenizing IRPSs (sIRPSs), sIRPS1-sIRPS9, respectively. Their effects on chicken peripheral lymphocyte proliferation in vitro were compared by MTT assay. The results showed that selenium polysaccharides at appropriate concentration could promote lymphocyte proliferation more significantly than unmodified polysaccharides, sEPS5 and sIRPS5 with stronger actions were picked out and injected into the chickens vaccinated with Newcastle disease vaccine in vivo tests. The peripheral lymphocyte proliferation and serum antibody titer were determined. The results showed that sEPS5 and sIRPS5 could elevate serum antibody titer and promote lymphocyte proliferation more significantly than unmodified polysaccharides, sEPS5 possessed the strongest efficacy. These results indicate that selenylation modification can significantly enhance the immune-enhancing activity of EPS and IRPS, and sEPS5 can be as a new-type immunopotentiator of chickens.

Effects of Selenylation Modification on Antioxidative Activities of Schisandra chinensis Polysaccharide

The selenylation modification of Schisandra chinensis polysaccharide (SCP) was conducted by the HNO₃–Na₂SeO₃ method respectively under nine conditions according to L₉(3⁴) orthogonal design. Nine selenizing SCPs, sSCP₁–sSCP₉, were obtained, and their antioxidant activities were compared. In vitro test, the free radical-scavenging rates of nine sSCPs were determined for DPPH., .OH and ABTS⁺. sSCP₁ presented the most significant effect, and could inhibit the nonenzymatic protein glycation. In vivo test, 14-day-old chickens were injected respectively with sSCP₁ and SCP, the serum contents of CAT, SOD and MDA were determined. The result showed that as compared with the SCP group, the SOD and CAT activities were significantly or numerically raised and MDA content was significantly or numerically lowered in the sSCP₁ group. These results indicate that selenylation modification can significantly enhance the antioxidant and antiglycative activity of SCP in vitro or in vivo. sSCP₁ possesses the best efficacy and its modification conditions can be as optimal modification conditions that were 200 mg of Na₂SeO₃ for 500 mg of SCP, reaction temperature of 50°C and reaction time of 6 h.