Investigation on bio-properties and in-vivo antioxidant potential of carrageenans against alloxan induced oxidative stress in Wistar albino rats

Potentials of Ulva spp.-derived sulfated polysaccharides as gelling agents with promising therapeutic effects

Ulvan, a sulfated polysaccharide extracted from Ulva spp., has garnered significant attention in the food and pharmaceutical industries due to its potential health benefits. These include immunomodulation, antiviral, anti-inflammatory, anti-hyperlipidemic, and anti-cancer effects. Nonetheless, practical applications in these fields remain limited due to an incomplete understanding of its gelation mechanisms. Additionally, the underlying mechanisms of its gelation have not been completely understood and thoroughly reviewed. The primary objective is to provide current insights into ulvan's gelling mechanisms and potential health impacts. This review also delves into the existing applications of ulvan polysaccharides. By unraveling these aspects, the information provided in this work is expected to deepen our understanding of ulvan's gelation mechanisms and its prospective role in enhancing health, holding promise for advancements in the fields of food science and disease prevention. This work's theoretical insights contribute significantly to a deeper understanding of these aspects, which holds paramount importance in unleashing the full potential of ulvan and elevating its scientific significance.

Nanotechnology-driven improvisation of red algae-derived carrageenan for industrial and bio-medical applications

Algae biomass has been recognized as feedstock with diverse application including production of biofuel, biofertilizer, animal feed, wastewater treatment and bioremediation. In addition, algae species are a potential reservoir of metabolites and polymers with potential to be utilized for biomedicine, healthcare and industrial purposes. Carrageenan is one such medicinally and industrially significant polysaccharide which is extracted from red algae species (Kappaphycus alvarezii and Eucheuma denticulatum, among the common species). The extraction process of carrageenan is affected by different environmental factors and the source of biomass, which can vary and significantly impact the yield. Diverse applications of carrageenan include hydrogel beads, bio-composites, pharmacological properties, application in cosmetics, food and related industries. Carrageenan biological activities including antioxidant, anti-inflammatory, antimicrobial, and antitumor activities are significantly influenced by sulfation pattern, yield percentage and molecular weight. In addition to natural biomedical potential of carrageenan, synergetic effect of carrageenan- nanocomposites exhibit potential for further improvisation of biomedical applications. Nanotechnology driven bio-composites of carrageenan remarkably improve the quality of films, food packaging, and drug delivery systems. Such nano bio-composites exhibit enhanced stability, biodegradability, and biocompatibility, making them suitable alternatives for drug delivery, wound-healing, and tissue engineering applications. The present work is a comprehensive study to analyze biomedical and other applications of Carrageenan along with underlying mechanism or mode of action along with synergetic application of nanotechnology.

Valorization of Kappaphycus alvarezii through extraction of high-value compounds employing green approaches and assessment of the therapeutic potential of κ-carrageenan

This study utilizes different emerging green extraction technologies to recover maximum value-added products from Kappaphycus alvarezii and evaluate their bio-functional properties. Using the supercritical fluid extraction (SFE) method, the total lipid yield of 0.21 ± 0.2 % was obtained from the biomass. Linoleic acid, eicosapentaenoic acid, arachidonic acid, γ-linolenic acid, and docosahexaenoic acid were present in higher concentrations (9.12 %) in the lipid extracted with SFE as compared to hexane (5.5 %). Using an ultrasonication assisted approach, ~56 % of κ-carrageenan was recovered from SFE residual biomass, which contains 28.5 ± 1.9 % sulfate content. It exhibited a monosaccharide content of 3,6-anhydrogalactose (~24 %) and galactose (~53 %), as well as rheological properties within FAO limitations that can be explored for food-grade applications. ~58 % of the total protein (12.5 %) from SFE residual biomass was recovered using subcritical water hydrolysis method. The effectiveness of κ-carrageenan in suppressing the 3CLpro of SARS-CoV-2 using in vitro and in silico approaches was investigated. κ-Carrageenan effectively inhibited the main protease by up to 93 % at 1.6 mg mL-1. In silico results revealed that κ-carrageenan successfully binds to the active site of the main protease while retaining the structural integrity and stability of protein-ligand complexes.

Rehashing Our Insight of Seaweeds as a Potential Source of Foods, Nutraceuticals, and Pharmaceuticals

In a few Southeast Asian nations, seaweeds have been a staple of the cuisine since prehistoric times. Seaweeds are currently becoming more and more popular around the world due to their superior nutritional value and medicinal properties. This is because of rising seaweed production on a global scale and substantial research on their composition and bioactivities over the past 20 years. By reviewing several articles in the literature, this review aimed to provide comprehensive information about the primary and secondary metabolites and various classes of bioactive compounds, such as polysaccharides, polyphenols, proteins, and essential fatty acids, along with their bioactivities, in a single article. This review also highlights the potential of seaweeds in the development of nutraceuticals, with a particular focus on their ability to enhance human health and overall well-being. In addition, we discuss the challenges and potential opportunities associated with the advancement of pharmaceuticals and nutraceuticals derived from seaweeds, as well as their incorporation into different industrial sectors. Furthermore, we find that many bioactive constituents found in seaweeds have demonstrated potential in terms of different therapeutic attributes, including antioxidative, anti-inflammatory, anticancer, and other properties. In conclusion, seaweed-based bioactive compounds have a huge potential to play an important role in the food, nutraceutical, and pharmaceutical sectors. However, future research should pay more attention to developing efficient techniques for the extraction and purification of compounds as well as their toxicity analysis, clinical efficacy, mode of action, and interactions with regular diets.

Perspectives of nanofibrous wound dressings based on glucans and galactans - A review

Wound healing is a complex and dynamic process that needs an appropriate environment to overcome infection and inflammation to progress well. Wounds lead to morbidity, mortality, and a significant economic burden, often due to the non-availability of suitable treatments. Hence, this field has lured the attention of researchers and pharmaceutical industries for decades. As a result, the global wound care market is expected to be 27.8 billion USD by 2026 from 19.3 billion USD in 2021, at a compound annual growth rate (CAGR) of 7.6 %. Wound dressings have emerged as an effective treatment to maintain moisture, protect from pathogens, and impede wound healing. However, synthetic polymer-based dressings fail to comprehensively address optimal and quick regeneration requirements. Natural polymers like glucan and galactan-based carbohydrate dressings have received much attention due to their inherent biocompatibility, biodegradability, inexpensiveness, and natural abundance. Also, nanofibrous mesh supports better proliferation and migration of fibroblasts because of their large surface area and similarity to the extracellular matrix (ECM). Thus, nanostructured dressings derived from glucans and galactans (i.e., chitosan, agar/agarose, pullulan, curdlan, carrageenan, etc.) can overcome the limitations associated with traditional wound dressings. However, they require further development pertaining to the wireless determination of wound bed status and its clinical assessment. The present review intends to provide insight into such carbohydrate-based nanofibrous dressings and their prospects, along with some clinical case studies.

Immunomodulatory, Antioxidant, Anticancer, and Pharmacokinetic Activity of Ulvan, a Seaweed-Derived Sulfated Polysaccharide: An Updated Comprehensive Review

Cancer is one of the most worldwide spread diseases and causes maximum death. Treatment of cancer depends on the host immune system and the type of drugs. The inefficiency of conventional cancer treatments as a result of drug resistance, nontargeted delivery, and chemotherapy-related negative side effects has caused bioactive phytochemicals to come into focus. As a result, recent years have seen an increase in research into screening and identifying natural compounds with anticancer properties. Recent studies on the isolation and use of polysaccharides derived from various marine algal species have revealed a variety of biological activities, including antioxidant and anticancer properties. Ulvan is a polysaccharide derived from various green seaweeds of the Ulva species in the family Ulvaceae. It has been demonstrated to have potent anticancer and anti-inflammatory properties through the modulation of antioxidants. It is vital to understand the mechanisms underlying the biotherapeutic activities of Ulvan in cancer and its role in immunomodulation. In this context, we reviewed the anticancer effects of ulvan based on its apoptotic effects and immunomodulatory activity. Additionally, we also focused on its pharmacokinetic studies in this review. Ulvan is the most conceivable candidate for use as a cancer therapeutic agent and could be used to boost immunity. Moreover, it may be established as an anticancer drug once its mechanisms of action are understood. Due to its high food and nutritive values, it can be used as a possible dietary supplement for cancer patients in the near future. This review may provide fresh perspectives on the potential novel role of ulvan, reveal a brand-new cancer-prevention strategy, and improve human health.

Kappaphycus Alvarezii Compound Powder Prevents Chemotherapy-Induced Intestinal Mucositis in BALB/c Mice

This study aimed to formulate Kappaphycus alvarezii compound powder containing Kappaphycus alvarezii powder (KP), cooked sorghum powder (SP), and longan powder (LP); which was evaluated for its therapeutic effects against chemotherapy-induced intestinal mucosal injury (CIMI). Based on rheological properties, sensory evaluation, and antioxidant activity and using single factor and response surface methodology, the optimal formula to develop the compound powder was determined to be 35% KP, 30% SP, 5% LP, and 30% xylitol. Thereafter, the efficacy of the compound powder was tested by feeding BALB/c mice with diets supplemented with the Kappaphycus alvarezii compound powder (3% and 5%) for 14 consecutive days. The chemotherapeutic drug 5-fluorouracil was intraperitoneally injected (50 mg/kg) in the mice to induce CIMI for the last three consecutive days. Compared to the CIMI mice, those fed 5% Kappaphycus alvarezii compound powder (HC) showed significantly improved the intestinal injury, increased mucin-2 secretion, and reduced TNF-α, IL-1β, IL-6, LT, and COX-2 levels. Furthermore, HC intake significantly reduced the Firmicutes-to-Bacteroidetes ratio, promoted the growth of beneficial bacteria, such as Alloprevotella, and inhibited the growth of harmful bacteria, such as Clostridium. In conclusion, HC has a protective effect against CIMI and provides a novel dietary strategy for patients undergoing chemotherapy.

Beneficial effects of seaweed-derived dietary fiber: Highlights of the sulfated polysaccharides

Seaweeds and their derivatives are important bioresources of natural bioactive compounds. Nutritional studies indicate that dietary fibers derived from seaweeds have great beneficial potentials in human health and can be developed as functional food. Moreover, sulfated polysaccharides are more likely to be the main bioactive components which are widely distributed in various species of seaweeds including Phaeophyceae, Rhodophyceae and Chlorophyceae. The catabolism by gut microbiota of the seaweeds-derived dietary fibers (DFs) may be one of the pivotal pathways of their physiological functions. Therefore, in this review, we summarized the latest results of the physiological characteristics of seaweed-derived dietary fiber and highlighted the roles of sulfated polysaccharides in the potential regulatory mechanisms against disorders. Meanwhile, the effects of different types of seaweed-derived dietary fiber on gut microbiota were discussed. The analysis of the structure-function correlations and gut microbiota related mechanisms and will contribute to further better applications in food and biotherapeutics.

Bioactive polysaccharides from red seaweed as potent food supplements: a systematic review of their extraction, purification, and biological activities

Most marine macroalgae such as red seaweeds are potential alternative sources of useful bioactive compounds. Beside serving as food source, recent studies have shown that red seaweeds are rich sources of bioactive polysaccharides. Red seaweed polysaccharides (RSPs) have various physiological and biological activities, which allow them to be used as immunomodulators, anti-obesity agents, and prebiotic ingredients. Lack of summary information and human clinical trials on the various polysaccharides from red seaweeds, however limits industrial-scale utilization of RSPs in functional foods. This review summarizes recent information on the approaches used for RSPs extraction and purification, mechanistic investigations of their biological activities, and related molecular principles behind their purported ability to prevent diseases. The information here also provides a theoretical foundation for further research into the structure and mechanism of action of RSPs and their potential applications in functional foods.

Extraction of Fucoidan from Turbinaria decurrens and the Synthesis of Fucoidan-Coated AgNPs for Anticoagulant Application

Brown seaweeds usually contain alginate as a major polymer. The second major sulfated polymer in brown seaweeds is fucoidan, which has huge potential in medicinal applications. In this study, the photosynthetic pigments from Turbinaria decurrens were first extracted using chloroform/methanol in the ratio of 1:1 (v/v), followed by fucoidan extraction with yields of 5.58% (crude) and 1.28% (purified fucoidan) from the dry weight of seaweed, whereas alginate was extracted with a yield of 14.7% DW of seaweed. The isolated fucoidan possessing anticoagulation property was identified and characterized as (1-3)-α-l-fucopyranosyl residues with sulfate groups primarily at the C4 position and to a lesser extent at the C2 position, whereas in the case of galactose, at the C3 and C6 positions. The AgNPs synthesized using isolated fucoidan exhibit strong anticoagulant activity and possess a good antibacterial property against Gram-negative clinical bacteria. Functional groups such as O-H, C-H, and S=O associated with sugar residues in sulfated fucoidan are involved in the synthesis of the nanoparticles with a spherical shape, size ranging from 10 to 60 nm, and showing polydispersity. From this study, we conclude that fucoidan-coated anionic AgNPs synthesized from T. decurrens have tremendous potential in drug development.

Sun-Dried and Air-Dried Kappaphycus alvarezii Attenuates 5-Fluorouracil-Induced Intestinal Mucositis in Mice

5-fluorouracil (5-FU)-induced intestinal mucositis (IM) often makes chemotherapy patients suffer from physical and psychological suffering. Kappaphycus alvarezii (KA) is known for its potent multiple biological activities from decades. In the current study, we explored the effect of sun-dried and air-dried Kappaphycus alvarezii as a whole food supplement on 5-FU-induced IM. Diets supplemented with sun-dried Kappaphycus alvarezii (SKA, 3%), air-dried Kappaphycus alvarezii (AKA, 3%), and 5-aminosalicylic acid (0.005%) for consecutive14 days. While intraperitoneal injection of 5-FU (50 mg/kg) induced IM for last three consecutive days, and IM was assessed by the disease activity index (DAI) and inflammatory cytokine levels. Pretreatment of KA could alleviate phenotypic index, inhibit the increase of DAI, and reverse villus/crypt ratio. On the 14th day, AKA significantly increased the weight growth rate of the mice. The intervention of SKA significantly reduced the level of TNF-α and IL-1β (P < 0.01, P < 0.01), while the intervention of AKA significantly inhibited the level of TNF-α, IL-1β, and LT (P < 0.01, P < 0.01, P < 0.001). Therefore, these results showed that KA as a whole food supplement might be prevent the 5-FU-induced IM. For the first time suggest that the use of AKA might be more effective than SKA despite exact mechanism still needs further study.

Antiviral Activity of Carrageenans and Processing Implications

Carrageenan and carrageenan oligosaccharides are red seaweed sulfated carbohydrates with well-known antiviral properties, mainly through the blocking of the viral attachment stage. They also exhibit other interesting biological properties and can be used to prepare different drug delivery systems for controlled administration. The most active forms are λ-, ι-, and κ-carrageenans, the degree and sulfation position being determined in their properties. They can be obtained from sustainable worldwide available resources and the influence of manufacturing on composition, structure, and antiviral properties should be considered. This review presents a survey of the antiviral properties of carrageenan in relation to the processing conditions, particularly those assisted by intensification technologies during the extraction stage, and discusses the possibility of further chemical modifications.

Chitosan/Hyaluronic acid/Alginate and an assorted polymers loaded with honey, plant, and marine compounds for progressive wound healing-Know-how

Biomaterials are being extensively used in regenerative medicine including tissue engineering applications, as these enhance tissue development, repair, and help in the process of angiogenesis. Wound healing is a crucial biological process of regeneration of ruptured tissue after getting injury to the skin and other soft tissue in humans and animals. Besides, the accumulation of microbial biofilms around the wound surface can increase the risk and physically obstruct the wound healing activity, and may even lead to amputation. Hence, in both acute and chronic wounds, prominent biomaterials are required for wound healing along with antimicrobial agents. This review comprehensively addresses the antimicrobial and wound healing effects of chitosan, chitin, cellulose acetate, hyaluronic acid, pullulan, bacterial cellulose, fibrin, alginate, etc. based wound dressing biomaterials fabricated with natural resources such as honey, plant bioactive compounds, and marine-based polymers. Due to their excellent biocompatibility and biodegradability, bioactive compounds derived from honey, plants, and marine resources are commonly used in biomedical and tissue engineering applications. Different types of polymer-based biomaterials including hydrogel, film, scaffold, nanofiber, and sponge dressings fabricated with bioactive agents including honey, curcumin, tannin, quercetin, andrographolide, gelatin, carrageenan, etc., can exhibit significant wound healing process in, diabetic wounds, diabetic ulcers, and burns, and help in cartilage repair along with good biocompatibility and antimicrobial effects. Among the reviewed biomaterials, carbohydrate polymers such as chitosan-based biomaterials are prominent and widely used for wound healing applications followed by hyaluronic acid and alginate-based biomaterials loaded with honey, plant, and marine compounds. This review first provides an overview of the vast natural resources used to formulate different biomaterials for the treatment of antimicrobial, acute, and chronic wound healing processes.

A Critical Review of the Abilities, Determinants, and Possible Molecular Mechanisms of Seaweed Polysaccharides Antioxidants

Oxidative stress induces various cardiovascular, neurodegenerative, and cancer diseases, caused by excess reactive oxygen species (ROS). It is attributed to the lack of sufficient antioxidant defense capacity to eliminate unnecessary ROS. Seaweeds are largely cultivated for their edible and commercial purposes. Excessive proliferation of some seaweeds has occurred in coastal areas, causing environmental and economic disasters, and even threating human health. Removing and disposing of the excess seaweeds are costly and labor-intensive with few rewards. Therefore, improving the value of seaweeds utilizes this resource, but also deals with the accumulated biomass in the environment. Seaweed has been demonstrated to be a great source of polysaccharides antioxidants, which are effective in enhancing the antioxidant system in humans and animals. They have been reported to be a healthful method to prevent and/or reduce oxidative damage. Current studies indicate that they have a good potential for treating various diseases. Polysaccharides, the main components in seaweeds, are commonly used as industrial feedstock. They are readily extracted by aqueous and acetone solutions. This study attempts to review the current researches related to seaweed polysaccharides as an antioxidant. We discuss the main categories, their antioxidant abilities, their determinants, and their possible molecular mechanisms of action. This review proposes possible high-value ways to utilize seaweed resources.

Ulvan, a Polysaccharide from Macroalga Ulva sp.: A Review of Chemistry, Biological Activities and Potential for Food and Biomedical Applications

The species of green macroalga belonging to the genus Ulva (family: Ulvaceae) are utilized in various fields, from food supplements to biomedical applications. Ulvan, a polysaccharide obtained from various Ulva species, has shown various biological activities, including antioxidant, anti-inflammatory, anticancer, antibacterial, and antiviral activities. To obtain the polysaccharide ulvan that can be utilized in various fields, it is necessary to understand the critical points that affect its physicochemical nature, the extraction procedures, and the mechanism of action for biological activities. This article discusses the physicochemical properties, extraction, isolation and characterization procedures and benefits in food and biomedical applications of ulvan. In conclusion, ulvan from Ulva sp. has the potential to be used as a therapeutic agent and also as an additional ingredient in the development of tissue engineering procedures.