Ultrasonic-assisted enzymatic extraction of a water soluble polysaccharide from dragon fruit peel and its antioxidant activity

Comparative elucidation of bioactive and antioxidant properties of red dragon fruit peel as affected by electromagnetic and conventional drying approaches

The effects of near-infrared (NIRD), mid-infrared (MIRD), far-infrared (FIRD), microwave (MWD), and hot air drying (HAD) on drying kinetic, colour, phytochemical composition, and antioxidant activity of red dragon fruit peel (RDFP) was evaluated. Results indicated that drying methods induced varying microstructural and chemical changes on RDFP, significantly influencing moisture removal rates and phytochemical retention. The lowest drying time was observed for MWD, while MIRD presented the highest drying time. FIRD drying was more favourable for retaining TPC, TFC, betacyanin and betaxanthin, while the ascorbic acid content was better retained during MIRD and NIRD. Enhancements in ABTS, CUPRAC and reducing power were associated with FIRD, and NIRD and MIRD enhanced DPPH and HRSA. Overall, chemical modifications induced by drying improved the phytochemical and antioxidant properties but presented adversative effects on ascorbic acid and DPPH. The study presented an essential background for the optimal drying of RDFP.

Isolation and purification of polysaccharides from Bupleurum marginatum Wall.ex DC and their anti-liver fibrosis activities

Bupleurum marginatum Wall.ex DC [Apiaceae] (BM)is widely grown in southwestern China, and the whole plant is used as Traditional Chinese Medicine (TCM). Polysaccharides are main natural products in lots of TCM and have been studied for their effects of reducing oxidative stress, anti-inflammation and immune regulation. Herein, we investigated the extraction techniques of Bupleurum marginatum Wall.ex DC polysaccharides (BMP), the identification of their key components, and their ability to inhibit liver fibrosis in both cellular and animal models. Component identification indicated that monosaccharides in BMP mainly consisted of glucose, galactose, mannose, rhamnose, arabinose, and xylose. In vivo analysis revealed that BMP provided significant protective effects on N-Nitroso dimethylamine (NDMA)-induced liver fibrosis rats through reducing hepatomegaly, reducing tissue inflammation, and reducing collagen deposition. BMP also improved the hepatobiliary system and liver metabolism in accord to reduce the serum levels of ALT, AST, ALP, r-GT, and TBIL. In addition, BMP could reduce the level of inflammation and fibrosis through inhibition of IL-1β and TGF-β1. Cellular studies showed that the BMP could provide therapeutic effects on lipopolysaccharide (LPS)-induced cellular fibrosis model, and could reduce the level of inflammation and fibrosis by decreasing the level of TGF-β1, IL-1β, and TNF-α. Our study demonstrated that BMP may provide a new therapy strategy of liver injury and liver fibrosis.

A novel digitonin/graphene oxide/iron oxide nanocomposite: synthesis, physiochemical characterization and antioxidant activity

In this work, iron oxide (Fe3O4) magnetic nanoparticles (MNPs) and graphene oxide (GO) nanosheets were prepared via the co-precipitation technique and the Modified Hummer method. Fe3O4 MNPs and GO nanosheets were combined to prepare Fe3O4/GO nanocomposite and subsequently conjugated with Digitonin (DIG) in order to obtain a dual-targeted delivery system based on DIG/Fe3O4/GO nanocomposite. SEM images reveal the presence of Fe3O4 MNPs at a scale of 100 nm, exhibiting dispersion between the GO nanosheets. Aggregation of the DIG/Fe3O4/GO nanocomposite was observed at various size scales. The XRD structural analysis confirms the crystal structure of the prepared samples. The Fe3O4 MNPs demonstrated the main XRD-diffracted peaks. Also, GO nanosheets exhibit crystalline characteristics on the (001) and (002) planes. The predominant peaks observed in the DIG/GO/Fe3O4 nanocomposite are attributed to the crystal phases of Fe3O4 MNPs. The FT-IR vibrational modes observed in the GO/DIG/Fe3O4 nanocomposite indicate the presence of crosslinking between GO nanosheet layers and the Fe3O4 MNPs. The antioxidant activity of the prepared samples was measured and the DIG/GO/Fe3O4 nanocomposite demonstrated a significantly high antioxidant activity in both 2-diphenyl-1-picrylhydrazyl (DPPH·) and 2,2-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS·+) tests.

Amphiphilic polyphenol incorporated hydrogel derived from mucoadhesive of Dillenia indica: Potential antioxidant and adsorbent

In this work, the mucoadhesive substances from the fruits and seeds of Dillenia indica (DI), a plant present abundantly in India, have been extracted and utilised to prepare a hydrogel. A synthetically prepared amphiphilic polyphenol (L) has been incorporated within the hydrogel network to enhance the hydrogelation property. Moreover, the DI-L hydrogel's total phenolic content and radical scavenging prospects have been investigated. The DI-L hydrogel has shown good, sensitive, and efficient adsorptive removal of Fe(III) from the aqueous medium with an adsorption capacity of 6.157 mg/g for an initial concentration of 10 mg/L of Fe(III) solution. As a result, these findings elucidate the most innovative application of transforming fruit mucoadhesive into sustainable environmental solutions.

Research progress in extraction, purification, structure of fruit and vegetable polysaccharides and their interaction with anthocyanins/starch

Fruits and vegetables contain polysaccharides, polyphenols, antioxidant enzymes, and various vitamins, etc. Fruits and vegetables polysaccharides (FVPs), as an important functional factor in health food, have various biological activities such as lowering blood sugar, blood lipids, blood pressure, inhibiting tumors, and delaying aging, etc. In addition, FVPs exhibit good physicochemical properties including low toxicity, biodegradability, biocompatibility. Increasing research has confirmed that FVPs could enhance the stability and biological activities of anthocyanins, affecting their bioavailability to improve food quality. Simultaneously, the addition of FVPs in natural starch suspension could improve the physicochemical properties of natural starch such as viscosity, gelling property, water binding capacity, and lotion stability. Hence, FVPs are widely used in the modification of natural anthocyanins/starch. A systematic review of the latest research progress and future development prospects of FVPs is very necessary to better understand them. This paper systematically reviews the latest progress in the extraction, purification, structure, and analysis techniques of FVPs. Moreover, the review also introduces the potential mechanisms, evaluation methods, and applications of the interaction between polysaccharides and anthocyanins/starch. The findings can provide important references for the further in-depth development and utilization of FVPs.

Sustainable approaches on industrial food wastes to value-added products - A review on extraction methods, characterizations, and its biomedical applications

The concept of zero waste discharge has been gaining importance in recent years towards attaining a sustainable environment. Fruit processing industries generate millions of tons of byproducts like fruit peels and seeds, and their disposal poses an environmental threat. The concept of extracting value-added bioactive compounds from bio-waste is an excellent opportunity to mitigate environmental issues. To date, significant research has been carried out on the extraction of essential biomolecules, particularly polysaccharides from waste generated by fruit processing industries. In this review article, we aim to summarize the different extraction methodologies, characterization methods, and biomedical applications of polysaccharides extracted from seeds and peels of different fruit sources. The review also focuses on the general scheme of extraction of polysaccharides from fruit waste with special emphasis on various methods used in extraction. Also, the various types of polysaccharides obtained from fruit processing industrial wastes are explained in consonance with the important techniques related to the structural elucidation of polysaccharides obtained from seed and peel waste. The use of seed polysaccharides as pharmaceutical excipients and the application of peel polysaccharides possessing biological activities are also elaborated.

Rare earths stick to rare cyanobacteria: Future potential for bioremediation and recovery of rare earth elements

Biosorption of metal ions by phototrophic microorganisms is regarded as a sustainable and alternative method for bioremediation and metal recovery. In this study, 12 cyanobacterial strains, including 7 terrestrial and 5 aquatic cyanobacteria, covering a broad phylogenetic diversity were investigated for their potential application in the enrichment of rare earth elements through biosorption. A screening for the maximum adsorption capacity of cerium, neodymium, terbium, and lanthanum was conducted in which Nostoc sp. 20.02 showed the highest adsorption capacity with 84.2-91.5 mg g^-1. Additionally, Synechococcus elongatus UTEX 2973, Calothrix brevissima SAG 34.79, Desmonostoc muscorum 90.03, and Komarekiella sp. 89.12 were promising candidate strains, with maximum adsorption capacities of 69.5-83.4 mg g^-1, 68.6-83.5 mg g^-1, 44.7-70.6 mg g^-1, and 47.2-67.1 mg g^-1 respectively. Experiments with cerium on adsorption properties of the five highest metal adsorbing strains displayed fast adsorption kinetics and a strong influence of the pH value on metal uptake, with an optimum at pH 5 to 6. Studies on binding specificity with mixed-metal solutions strongly indicated an ion-exchange mechanism in which Na⁺, K⁺, Mg²⁺, and Ca²⁺ ions are replaced by other metal cations during the biosorption process. Depending on the cyanobacterial strain, FT-IR analysis indicated the involvement different functional groups like hydroxyl and carboxyl groups during the adsorption process. Overall, the application of cyanobacteria as biosorbent in bioremediation and recovery of rare earth elements is a promising method for the development of an industrial process and has to be further optimized and adjusted regarding metal-containing wastewater and adsorption efficiency by cyanobacterial biomass.

A review on shellfish polysaccharides: Extraction, characterization and amelioration of metabolic syndrome

Shellfish are diverse, widely distributed organisms that are a rich source of biological resources. Polysaccharides are an important components in shellfish, hence a great deal of attention has been directed at isolation and characterization of shellfish polysaccharides because of their numerous health benefits. Differences in shellfish species, habits, and environment result in the diversity of the structure and composition of polysaccharides. Thus, shellfish polysaccharides possess special biological activities. Studies have shown that shellfish polysaccharides exert biological activities, including antioxidant, antitumor, immune-regulation, hypolipidemic, antihypertensive, and antihyperglycemic effects, and are widely used in cosmetics, health products, and medicine. This review spotlights the extraction and purification methods of shellfish polysaccharides and analyses their structures, biological activities and conformational relationships; discusses the regulatory mechanism of shellfish polysaccharides on hyperlipidemia, hypertension, and hyperglycemia caused by lipid metabolism disorders; and summarizes its alleviation of lipid metabolism-related diseases. This review provides a reference for the in-depth development and utilization of shellfish polysaccharides as a functional food to regulate lipid metabolism-related diseases. To achieve high value utilization of marine shellfish resources while actively promoting the development of marine biological industry and health industry.

Extraction Optimization, UHPLC-Triple-TOF-MS/MS Analysis and Antioxidant Activity of Ceramides from Sea Red Rice Bran

As a new type of salt-tolerant rice, sea red rice contains more minerals, proteins, and lipid compounds, and, in particular, its by-product rice bran may be used to replace other commercial rice brans as the main source of ceramides (Cers). However, the extraction rate of Cers is generally low, and it is crucial to seek an efficient extraction method. This study optimized the ultrasonic-assisted extraction of Cers from sea red rice bran using response surface methodology (RSM) and obtained a Cers yield of 12.54% under optimal conditions involving an extraction temperature of 46 °C, an extraction time of 46 min, and a material-to-liquid ratio of 5 g/mL. The Cers content in sea red rice bran was preliminarily analyzed using thin-layer chromatography, and the Cers content was determined via UHPLC-Triple-TOF-MS/MS after purification and separation using silica column chromatography. Forty-six different types of Cers were identified in sea red rice bran, of which Cer 18:0/24:0 (2OH), Cer 18:0/26:0, Cer 18:0/26:0 (2OH), and Cer 18:0/24:0 accounted for 23.66%, 17.54%, 14.91%, and 11.96%. Most of the Cers structures were mainly composed of sphingadienine. A biological activity assay indicated that Cers extracted from sea red rice bran had significant antioxidant and anti-aging properties. These findings indicate that the extracted Cers show great potential for applications in the cosmetic and pharmaceutical industries.

Isolation and Investigation of Natural Rare Earth Metal Chelating Agents From Calothrix brevissima - A Step Towards Unraveling the Mechanisms of Metal Biosorption

In this study water soluble compounds that form complexes with Rare Earth Elements (REE) and other metals were isolated from Calothrix brevissima biomass with chromatographic methods for the first time. Molecular characterization showed that the isolated compounds are most likely polysaccharides comprised of arabinose, xylose, mannose, galactose and glucose. FT-IR analysis revealed functional groups involved in the binding mechanism of Tb are likely sulfate- and to a lesser extend hydroxyl-groups. The binding specificity of the isolated compounds was investigated with different metal solutions. Here, ions of the alkali and alkaline earth metals Na, K, Mg and Ca showed no competition for Tb-binding even at 10-fold excess concentration. Ions of the elements Co and Pb on the other hand replaced Tb at higher concentrations. Addition of the isolated compounds significantly reduced the precipitation of Eu at pH-values between 6.7 and 9.5, indicating that the interaction between the isolated chelators and Rare Earth Metals is stable even at high pH-values.

Recent advances in extraction technologies for recovery of bioactive compounds derived from fruit and vegetable waste peels: A review

Fruits and vegetables are the most important commodities of trade value among horticultural produce. They are utilized as raw or processed, owing to the presence of health-promoting components. Significant quantities of waste are produced during fruits and vegetables processing that are majorly accounted by waste peels (∼90-92%). These wastes, however, are usually exceptionally abundant in bioactive molecules. Retrieving these valuable compounds is a core objective for the valorization of waste peel, besides making them a prevailing source of beneficial additives in food and pharmaceutical industry. The current review is focused on extraction of bioactive compounds derived from fruit and vegetable waste peels and highlights the supreme attractive conventional and non-conventional extraction techniques, such as microwave-assisted, ultrasound assisted, pulsed electric fields, pulsed ohmic heating, pressurized liquid extraction, supercritical fluid extraction, pressurized hot water, high hydrostatic pressure, dielectric barrier discharge plasma extraction, enzyme-assisted extraction and the application of "green" solvents say as well as their synergistic effects that have been applied to recover bioactive from waste peels. Superior yields achieved with non-conventional technologies were identified to be of chief interest, considering direct positive economic consequences. This review also emphasizes leveraging efficient, modern extraction technologies for valorizing abundantly available low-cost waste peel, to achieve economical substitutes, whilst safeguarding the environment and building a circular economy. It is supposed that the findings discussed though this review might be a valuable tool for fruit and vegetable processing industry to imply an economical and effectual sustainable extraction methods, converting waste peel by-product to a high added value functional product.

Valorization of Gleditsia triacanthos Invasive Plant Cellulose Microfibers and Phenolic Compounds for Obtaining Multi-Functional Wound Dressings with Antimicrobial and Antioxidant Properties

Gleditsia triacanthos is an aggressive invasive species in Eastern Europe, producing a significant number of pods that could represent an inexhaustible resource of raw material for various applications. The aim of this study was to extract cellulose from the Gleditsia triacanthos pods, characterize it by spectrophotometric and UHPLC-DAD-ESI/MS analysis, and use it to fabricate a wound dressing that is multi-functionalized with phenolic compounds extracted from the leaves of the same species. The obtained cellulose microfibers (CM) were functionalized, lyophilized, and characterized by ATR-FTIR and SEM. The water absorption and retention capacity as well as the controlled release of phenolic compounds with antioxidant properties evaluated in temporal dynamics were also determined. The antimicrobial activity against reference and clinical multi-drug-resistant Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter cloacae, Candida albicans, and Candida parapsilosis strains occurred immediately after the contact with the tested materials and was maintained for 24 h for all tested microbial strains. In conclusion, the multi-functionalized cellulose microfibers (MFCM) obtained from the reproductive organs of an invasive species can represent a promising alternative for the development of functional wound dressings with antioxidant and antimicrobial activity, as well as being a scalable example for designing cost-effective, circular bio-economy approaches to combat the accelerated spread of invasive species.

Mucilage Extracted from Dragon Fruit Peel (Hylocereus undatus) as Flocculant for Treatment of Dye Wastewater by Coagulation and Flocculation Process

Dye wastewater from textile industries shows very low biodegradability due to high molecular weight and complex structures of dyes. So far, the most simple method for treatment of this type of wastewater has been coagulation and flocculation. This study determined the removal of turbidity and other pollutants from dye wastewater by mucilage extracted from the peel of dragon fruit (Hylocereus undatus) and its effect in reducing synthetic chemical polyaluminum chloride (PACl) used in coagulation and flocculation (CF) process. The removal of turbidity in a sequent CF process using PACl and dragon fruit mucilage was investigated based on Jar tests. Maximum coagulation efficiencies of PACl were typically observed at pH 4.0-6.0 and PACl concentrations of about 100-150 mg/L depending on types of wastewater, whereas optimal settling times were 30-60 minutes, respectively. The addition of dragon fruit mucilage (0.5-50 mg/L) after PACl (75-245 mg/L) resulted in turbidity removal efficiencies up to 95%. The addition of mucilage extracted from dragon fruit peels was proven to increase turbidity removal efficiency and decrease PACl use. The increase of turbidity removal was often estimated at 10-32%, whereas PACl used was about 3-10% less compared to total PACl needed for obtaining comparable efficiency when used alone. The flocculation activity of mucilage was also compared to polyacrylamide (PAM)—a synthetically organic flocculant. Since the peel of a dragon fruit is an abundant agriculture waste in Vietnam, using its extracted mucilage as a flocculant is an environmentally friendly method.

Trends in the extraction, purification, characterisation and biological activities of polysaccharides from tropical and sub-tropical fruits - A comprehensive review

Tropical and sub-tropical fruits are tremendous sources of polysaccharides (PSs), which are of great interest in the human welfare system as natural medicines, food and cosmetics. This review paper aims to highlight the recent trends in extraction (conventional and non-conventional), purification and analytic techniques of fruit polysaccharides (FPSs). The chemical structure and biological activities, such as immunomodulatory, anti-cancer, anti-oxidant, anti-inflammatory, anti-viral, anti-coagulant and anti-diabetic effects, of PSs extracted from 53 various fruits were compared and discussed. With this wide coverage, a total of 172 scientific articles were reviewed and discussed. This comprehensive survey from previous studies suggests that the FPSs are non-toxic and highly biocompatible. In addition, this review highlights that FPSs might be excellent functional foods as well as effective therapeutic drugs. Finally, the future research advances of FPSs are also described. The content of this review will promote human wellness-based food product development in the future.

Polysaccharides from loquat (Eriobotrya japonica) leaves: Impacts of extraction methods on their physicochemical characteristics and biological activities

Impacts of hot water extraction (HWE), pressurized water extraction (PWE), high-speed shearing homogenization extraction, microwave assisted extraction (MAE), ultrasound assisted extraction (UAE), ultrasound assisted enzymatic extraction, and ultrasound-microwave assisted extraction (UMAE) on physicochemical characteristics and bioactivities of polysaccharides from loquat (Eriobotrya japonica) leaves (LLPs) were investigated. Results showed that the degrees of esterification, contents of phenolics and uronic acids, constituent monosaccharides, apparent viscosities, and molecular weights of LLPs varied by different extraction methods. Bioactivities of LLPs were also significantly affected by different extraction methods. The high molecular weight and high degree of esterification of LLP-W and LLP-P extracted by HWE and PWE, respectively, might contribute to their strong binding capacities. The strong antioxidant activities and inhibitory effects on α-amylase and α-glucosidase were found in LLP-M and LLP-U extracted by MAE and UAE, respectively, which might be attributed to their contents of uronic acids, contents of total phenolics, and molecular weights. The low molecular weights and viscosities of LLP-U and LLP-UM extracted by UMAE might contribute to their strong prebiotic effects. These findings could provide scientific foundations for selecting appropriate extraction methods to obtain LLPs with desired bioactivities for applications in the pharmaceutical and functional food industries.

Ultrasonic-assisted enzymatic extraction of Sparassis crispa polysaccharides possessing protective ability against H2O2-induced oxidative damage in mouse hippocampal HT22 cells

Extraction optimization, structural characterization, and neuroprotective effects of polysaccharides from Sparassis crispa.

Optimization of ultrasonic-assisted enzymatic extraction of polysaccharides from thick-shell mussel (Mytilus coruscus) and their antioxidant activities

This study aimed to obtain the purified fractions of Mytilus coruscus polysaccharides (MCPs) and investigate their antioxidant activities. MCPs were prepared through ultrasonic-assisted enzymatic extraction optimized by employing the response surface methodology. A single-factor experiment was conducted using the Box-Behnken design to determine the optimum extraction conditions of MCPs. The ultrasonic power was 60 W, liquid-to-material ratio was 30 mL/g, extraction time was 36 min, extraction temperature was 64 °C, enzyme concentration was 3.2%, and polysaccharide extraction yield was 12.86% ± 0.12%. A novel polysaccharide (MCP1-2) was obtained after the purification with AB-8 macroporous resin, DEAE Sepharose Fast Flow, and Sepharose CL-6B column. The molecular weight of MCP1-2 was estimated to be 134.9 kDa according to high-performance gel permeation chromatography. High-pressure liquid-phase chromatography results showed that MCP1-2 contained mannose, rhamnose, glucuronic acid, glucose, galactose, and L-Fuc at a molar ratio of 1.53:1:4.83:81.82:2.36:1.51. Infrared and NMR spectroscopies confirmed that MCP1-2 possessed α- and β- configurations. The antioxidant activities of MCP1-2 were investigated in vitro, and the results showed that MCP1-2 had good antioxidant activity and can be used as a natural antioxidant in food.

Optimization of the extraction, preliminary characterization, and anti-inflammatory activity of crude polysaccharides from the stems of Trapa quadrispinosa

A novel method was developed using pressurized-assisted extraction (PAE) to efficiently extract crude Trapa quadrispinosa polysaccharides (TQCPS) from plant stems, and the extraction process was optimized using response surface methodology (RSM). At a water-to-material fixed ratio of 30 mL g⁻¹, the highest yield of 3.72 ± 0.13% was obtained under the optimum conditions of extraction time of 32 min, extraction temperature at 47 °C, and extraction pressure at 1.87 Mpa, which were in agreement with the predicted value of 3.683%. Compared with conventional hot water extraction (HWE), the PAE method remarkably enhanced the extraction yield with the further advantages of short extraction time and low extraction temperature. The preliminary characteristics of TQCPS were analyzed through UV-vis, FT-IR, and chemical composition analysis. In subsequent anti-inflammatory studies, when RAW 264.7 mouse macrophage cells were treated with TQCPS, satisfactory anti-inflammatory activity was observed, and TQCPS significantly suppressed the release of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) and synchronously restrained the expression levels of inducible nitric oxide synthase (iNOS), TNF-α, and IL-6 mRNA induced by lipopolysaccharide (LPS) in a dose-dependent manner. These results indicate that PAE is a technology that can be used for efficient extraction of polysaccharides from medicinal plants, and TQCPS can be explored as a potential anti-inflammatory agent in medicine.

The high-yield TQCPS extracted by PAE presented good anti-inflammatory activity.