Exploring Cold plasma technology: Enhancements in Carob seed germination, phytochemical Composition, and antioxidant activity.

The cultivation of carob tree does not need many climatic and ecological requirements. The main limit to its large-scale cultivation is the defects for propagation with seeds. Addressing this, our study evaluated the effect of cold plasma pretreatment on carob seed germination. Impressively, cold plasma showcased beneficial effects by significantly increasing water uptake in seeds (CS: 1.71 ± 0.59; PS/3.99 ± 1.56) and decreasing the contact angle from 80.7° to 57.9°, enhancing the seed surface's hydrophilicity. While the germination rate enhancement was subtle, the treatment presented an innovative route to modifying the seed's physiochemical properties. Specifically, storage proteins like albumin, globulin, and prolamin were notably reduced (Albumin (from 7.67 to 4.95 mg/g DW), Globulin (from 8.52 to 5.80 mg/g DW) and Prolamin (from 3.53 to 1.66 mg/g DW)). Additionally, there was a decline in the overall content of polyphenols (from 846.88 to 760.94 mg GAE/100g DW) and flavonoids (from 790.93 to 502.95 mg GAE/100g DW) and a decrease in the ferric reducing power (from 34.48 to 26.39 mg AAE/g DW). However, radical scavenging activity remained consistent. Intriguingly, FTIR-ATR spectral analysis post plasma treatment indicated oxidative alterations in the seed coat, marked by a distinctive intensity at 1732 cm⁻1. This investigation suggests that the application of eco-friendly technology could provide improvements in seed surface's hydrophilicity, but appropriate conditions could be chosen to increase germination efficiency.

The genus Polygonum: An updated comprehensive review of its ethnomedicinal, phytochemical, pharmacological activities, toxicology, and phytopharmaceutical formulation.

Polygonum is a plant genus that includes annual and perennial species and is found at various temperatures, from northern temperate regions to tropical and subtropical areas. The genus Polygonum has been used for centuries for various disorders, including hypertension, intestinal and stomach pain, dysuria, jaundice, toothaches, skin allergies, hemorrhoids, cardiac disorders, kidney stones, hemostasis, hyperglycemia, and others. Various databases, including Google Scholar, Scifinder, ScienceDirect, PubMed, Scopus, ResearchGate, and Web of Science, were utilized to collect pertinent scientific literature data. According to bibliographic studies, the Polygonum genus possesses various compounds from different families, including phenolic acids (gallic acid, caffeic acid, quinic acid, p-coumaric acid, ferulic acid, protocatechuic acid, chlorogenic acid, and many other compounds), flavonoids (quercetin, catechin, epicatechin, quercitrin, kaempferol, myricetin, etc.), tannins, stilbenes (polydatin and resveratrol), terpenes (α-pinene, ß-caryophyllene and ß-caryophyllene oxide, bisabolene, ß-farnesene, etc.), fatty acids (decanoic acid, lauric acid, linoleic acid, oleic acid, palmitic acid, stearic acid, dodecanoic acid), polysaccharides, and others. Various chemical and biological activities (in vitro and in vivo), such as antioxidant, antimicrobial, anticancer, antitumor, anti-inflammatory, antidiabetic, antiparasitic, hepatoprotective, neuropharmacological, gastroprotective, diuretic, antipyretic, and others, have been described in several biological studies involving this species. An updated summary of Polygonum species and their ethnomedicinal, phytochemical, toxicological, pharmacological, and phytopharmaceutical formulations is necessary. Considering the numerous potentialities of the Polygonum species and their wide-ranging use, it is extremely essential to provide knowledge by compiling the accessible literature to identify the topics of intense investigation and the main gaps to better design future studies. The objective of this review is to give readers a better understanding, greater comprehension, and in-depth knowledge of the genus Polygonum's traditional applications, phytochemistry, pharmacology, toxicological features, and galenic formulation. Several species of this genus have been detailed in this review, including those that were frequently used in traditional medicine (P. minus, P. aviculare, P. hydropiper, P. cuspidatum, and P. multiflorum) and many of the genus' therapeutic species, like P. equisetiforme, which do not get enough attention.

GC-MS profiling, antifeedant, nematicidal and phytotoxic effects of essential oils of two subspecies of Eucalyptus flocktoniae (Maiden) Maiden.

This work presents the biocidal effects and chemical compositions of two essential oils (EOs) obtained by hydrodistillation of Eucalyptus flocktoniae subsp. flocktoniae and E. flocktoniae subsp. hebes. The two subspecies studied had different chemical composition, when analysed by gas chromatography coupled to mass spectrometry with 1,8-cineole (56.98%), trans-pinocarveol (20.38%) and α-pinene (5.86%) being the major components of E. flocktoniae subsp. flocktoniae and spathulenol (25.09%), p-cymene (21.20%), 1,8-cineole (10.74%) and α-pinene (8.93%) are the major components of E. flocktoniae subsp. hebes. These oils were evaluated for their insect antifeedant, nematicidal and phytotoxic activities. The biocidal tests showed that E. flocktoniae subsp. hebes was the most active against Myzus persicae and Rhopalosiphum padi. While, E. flocktoniae subsp. flocktoniae was not antifeedant. None of the investigated EOs were active against both Spodoptera littoralis and Meloidogyne javanica root-knot nematode. Moreover, the EOs extracted from these two subspecies showed a significant phytotoxic effect.

Ultrasonic treatment of rice bran protein-tannic acid stabilized oil-in-water emulsions: Focus on microstructure, rheological properties and emulsion stability.

Rice bran protein (RBP)-tannic acid (TA) complex was prepared and the RBP-TA emulsions were subjected to ultrasonic treatment with different powers. Ultrasonic treatment has a positive effect on improving the properties of RBP-TA emulsion. This study investigated the influence of different ultrasonic power levels on the physicochemical properties, microstructure, rheological properties, and stability of emulsions containing RBP-TA. Under the ultrasonic treatment of 400 W, the particle size, zeta potential, and adsorbed protein content of the RBP-TA emulsion were 146.86 nm, -20.7 eV, and 61.91%, respectively. At this time, the emulsion had the best emulsifying properties, apparent viscosity, energy storage modulus and loss modulus. In addition, the POV and TBARS values of RBP-TA emulsions were 6.12 and 7.60 mmol/kg, respectively. The thermal, salt ion, pH and oxidative stability of the emulsions were investigated, and it was shown that ultrasonic treatment was effective in improving the stability of RBP-TA emulsions.

Phenolic Profiling, Antioxidant, and Antibacterial Activities of Selected Medicinal Plants from Tunisia.

Phytochemical screening of aqueous extract from six medicinal wild plants grown in South-eastern of Tunisia: Atriplex halimus, Teucrium polium, Moricandia arvensis, Deverra tortuoa, Haplophyllum tuberculatum and Polygonum equisetiforme were evaluated. Both decoction and ultrasound assisted extraction were used. Antioxidant, antibacterial proprieties, and phenolic profiling, using LC-ESI-MS method, were assessed. Total polyphenols, flavonoids, and condensed tannins contents ranged from 7.47±0.19 to 22.25±0.49 mg GAE/g Dw, 5.47±0.06 to 7.55±0.07 mg RE/g Dw, and 0.33±0.02 to 19.43±0.64 mg TAE/g Dw, respectively. Moreover, the reducing power and DPPH tests showed that P. equisetiforme (EC50 : 12.50±0.50 µg/ml; DPPH⋅+ : 213.49±4.24 mg TEAC/g DW), T. polium (EC50 : 25.00±1.00 µg/ml; DPPH⋅+ : 181.39±9.47 mg TEAC/g DW) as well as H. tuberculatum (EC50 : 56.25±0.25 µg/ml; DPPH⋅+ : 177.83±5.85 mg TEAC/g DW) extracts were the most effective natural antioxidants. For anti-bacterial activity, the ultrasonic extract of H. tuberculatum showed the highest activity against both P. aeruginosa (13.50±0.71 mm) and S. aureus (13.00±0.00 mm) at 10 mg/ml. Furthermore 24 phenolic compounds were identified, with predominance of quinic acid, gallic acid, protocatechuic acid, syringic acid, p-coumaric acid, trans-ferulic acid, catechin (+), trans-cinnamic and silymarin. These results were further consolidated by to heatmap clustering with P. equisetiforme, H. tuberculatum, T. polium as the main antioxidant and antibacterial sources which supports their domestication and industrial use.

Date Seeds (Phoenix dactylifera): Antioxidant Potential and Profile of Free and Bound Polyphenols from Different Cultivars.

In this study, the antioxidant activities and detailed phenolic profiling of extracts from seven cultivars of date seeds were investigated. Significant differences were detected among cultivars. Total phenolic content (TP) ranged between 135.9±12.1 and 284.86±21.9 mg GAE/g DM. The total flavonoid value varied between 34.20±0.34 and 94.46±1.04 mg RE/g DM. The condensed tannin ranged from 24.17±1.13 to 201.60±9.95 mg CTE/g DM. Phloroglucinolysis was used to depolymerize the bound polyphenols. Results show the presence of phenolic acids: Hydroxybenzoic acid, hydroxycinnamic acid, and a high amount of flavan-3ols (monomers, dimers, and trimers). Before depolymerization, the highest amount of total polyphenols was identified in Kenta (8.48 g/kg) and the lowest was detected in Hessa (4.74 g/kg). After depolymerization, the flavan-3-ols increased significantly, ranging between 46.91g/kg in Hessa and 72.38 g/kg in Deglet Nour, with a high degree of polymerization (DP) in all cultivars. It can be concluded that date seeds represent a good source of bioactive compounds.

Influence of Extraction Techniques and Solvents on the Antioxidant and Biological Potential of Different Parts of Scorzonera undulata.

The genus Scorzonera has various medicinal values. Species belonging to this genus were traditionally used as drugs or in food. The current study aimed to determine the phytochemical composition, antioxidant activity, and biological properties of the tuber, leaf, and flower of Scorzonera undulata extracts, collected from the southwest of Tunisia. Phenolic compounds from the three parts were extracted using two solvents (water and ethanol) and two extraction techniques (maceration and ultrasound). The total phenolic content was measured by the Folin-Ciocalteu assay. Furthermore, the chemical composition of Scorzonera undulata extract was also investigated by the LC-ESI-MS method using phenolic acid and flavonoid standards. The variation of the extraction methods induced a variation in the real potentialities of the three parts in terms of bioactive molecules. However, the aerial part of S. undulata (leaves and flowers) showed, in general, the highest phenolic contents. Twenty-five volatile compounds have been detected by GC-MS in S. undulata extracts; among them, fourteen were identified before derivatization. The DPPH test showed that the aerial part of the plant has a higher antioxidant activity compared to the tuber (25.06% at 50 µg/mL for the leaf ethanolic extract obtained by ultrasound extraction). For most biological activities (anti-Xanthine, anti-inflammatory, and antidiabetic (alpha-amylase and alpha-glucosidase)), the aerial parts (flowers and leaves) of the plant showed the highest inhibition than tubers.

Disinfection of corona and myriad viruses in water by non-thermal plasma: a review.

Nowadays, in parallel to the appearance of the COVID-19 virus, the risk of viruses in water increases leading to the necessity of developing novel disinfection methods. This review focuses on the route of virus contamination in water and introduces non-thermal plasma technology as a promising method for the inactivation of viruses. Effects of essential parameters affecting the non-thermal discharge for viral inactivation have been exposed. The review has also illustrated a critical discussion of this technology with other advanced oxidation processes. Additionally, the inactivation mechanisms have also been detailed based on reactive oxygen and nitrogen species.

Synthesis and Characterization of TiO2 Nanotubes (TiO2-NTs) with Ag Silver Nanoparticles (Ag-NPs): Photocatalytic Performance for Wastewater Treatment under Visible Light.

In this work, we present the influence of the decoration of TiO2 nanotubes (TiO2-NTs) with Ag silver nanoparticles (Ag-NPs) on the photocatalysis of emerging pollutants such as the antibiotic diclofenac sodium. The Ag-NPs were loaded onto the TiO2-NTs by the anodization of metallic titanium foils. Diclofenac sodium is an emerging pollutant target of the pharmaceutical industry because of its negative environmental impact (high toxicity and confirmed carcinogenicity). The obtained Ag-NP/TiO2-NT nanocomposites were characterized by X-ray diffraction (XRD), photoluminescence spectroscopy (PL), scanning electron microscopy (SEM), transmission spectroscopy (TEM), and X-ray photoelectron spectroscopy (XPS). In order to study the photocatalytic behavior of Ag-NPs/TiO2-NTs with visible cold LEDs, the possible photocatalytic mechanism of antibiotic degradation with reactive species (O2°- and OH°) was detailed. Moreover, the Langmuir-Hinshelwood model was used to correlate the experimental results with the optimized catalyst. Likewise, reuse tests showed the chemical stability of the catalyst.

Chemically modified magnetic immobilized phospholipase A1 and its application for soybean oil degumming.

In this paper, the free Phospholipase A1 (PLA1) was immobilized on a magnetic carrier. The average particle diameter of the magnetic carrier was 97 ± 1.3 nm, and the average particle diameter of the magnetically immobilized PLA1 was 105 nm ± 1.3 nm. The enzyme activity was 1940.5 U/g. The magnetic enzyme was chemically modified with formaldehyde, dextran-aldehyde, and dextran-aldehyde-glycine. The proportions of primary amino groups in the modified magnetic immobilized enzyme PLA1 were 0, 53.5% and 47.3%, respectively. The optimum pH of the enzyme after chemical modification was 6.5. When the system temperature was 60 °C, the magnetically immobilized PLA1 modified with dextran-aldehyde-glycine had the optimal activity and stability. This chemically modified magnetic immobilized PLA1 was applied to soybean oil degumming at 60 °C, 6.5 h (reaction time), and 0.10 mg/kg (enzyme dosage). The phosphorus content in the degummed oil was 9.2 mg/kg. The relative enzyme activity was 77.6% after 7 reuses which would be potentially advantageous for industrial applications. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s13197-021-05017-4).

Review on inactivation of airborne viruses using non-thermal plasma technologies: from MS2 to coronavirus.

Although several non-thermal plasmas (NTPs) technologies have been widely investigated in air treatment, very few studies have focused on the inactivation mechanism of viruses by NTPs. Due to its efficiency and environmental compatibility, non-thermal plasma could be considered a promising virus-inactivation technology. Plasma is a partly or fully ionized gas including some species (i.e., electrons, free radicals, ions, and neutral molecules) to oxidize pollutants or inactivate harmful organisms. Non-thermal plasmas are made using less energy and have an active electron at a much higher temperature than bulk gas molecules. This review describes NTPs for virus inactivation in indoor air. The different application processes of plasma for microorganism inactivation at both laboratory and pilot-scale was also reviewed This paper reports on recent advances in this exciting area of viral inactivation identifying applications and mechanisms of inactivation, and summarizing the results of the latest experiments in the literature. Moreover, special attention was paid to the mechanism of virus inactivation. Finally, the paper suggests research directions in the field of airborne virus inactivation using non-thermal plasma.

Freeze-dried, oven-dried, and microencapsulation of essential oil from Allium sativum as potential preservative agents of minced meat.

The present study was conducted to compare the antibacterial activity of oven-dried and freeze-dried Allium sativum along with its spray-dried microencapsulated essential oil in the preservation of minced beef meat. Allium sativum extracts were tested against mesophilic aerobic microorganisms, coagulase-positive staphylococci, Escherichia coli, Salmonella sp., and the sulfite-reducing anaerobes. A difference between the chemical compositions of powders obtained by the conventional oven-drying and freeze-drying has been verified by HPLC-MS2, freeze-dried fresh garlic powder contains 74% of allicin, and 12% cysteine sulfoxides comparing to the oven-drying garlic powder in which is detected two thiosulfinate isomers: allicin (67%) and allyl-1-propenyl thiosulfinate (21%). CIELAB color analysis was performed to assess the effect of drying temperature on powders. The microflora-inhibiting effect of freeze-dried fresh garlic and the spray-dried microencapsulated essential oil at a concentration of 20% represents a promising way to be used in food systems such as meat and meat products preservation, at 4-8°C.

Advances on Antiviral Activity of Morus spp. Plant Extracts: Human Coronavirus and Virus-Related Respiratory Tract Infections in the Spotlight.

(1) Background: Viral respiratory infections cause life-threatening diseases in millions of people worldwide every year. Human coronavirus and several picornaviruses are responsible for worldwide epidemic outbreaks, thus representing a heavy burden to their hosts. In the absence of specific treatments for human viral infections, natural products offer an alternative in terms of innovative drug therapies. (2) Methods: We analyzed the antiviral properties of the leaves and stem bark of the mulberry tree (Morus spp.). We compared the antiviral activity of Morus spp. on enveloped and nonenveloped viral pathogens, such as human coronavirus (HCoV 229E) and different members of the Picornaviridae family-human poliovirus 1, human parechovirus 1 and 3, and human echovirus 11. The antiviral activity of 12 water and water-alcohol plant extracts of the leaves and stem bark of three different species of mulberry-Morus alba var. alba, Morus alba var. rosa, and Morus rubra-were evaluated. We also evaluated the antiviral activities of kuwanon G against HCoV-229E. (3) Results: Our results showed that several extracts reduced the viral titer and cytopathogenic effects (CPE). Leaves' water-alcohol extracts exhibited maximum antiviral activity on human coronavirus, while stem bark and leaves' water and water-alcohol extracts were the most effective on picornaviruses. (4) Conclusions: The analysis of the antiviral activities of Morus spp. offer promising applications in antiviral strategies.

Application of magnetic immobilized papain on passivated rice bran lipase.

Magnetically immobilized papain is prepared by magnetic Fe3O4/P (GMA-EDGMA-St) composite carrier with the addition of 12.0 mg/mL papain, 5.0% glutaraldehyde and 4 hour reaction time. The characteristic absorption peaks of each functional group were shown by infrared light. The X-diffraction pattern showed six main diffraction peaks with a magnetization value of 37.60 emu/g. TEM and SEM showed that free papain was immobilized on the magnetic carrier with an average particle size of 196 nm. The concentration of the enzyme was 122.25 mg/g, enzyme activity recovery was 55,263 U/g, compared with the free enzyme, the magnetically immobilized papain indicated higher acid-base tolerance and thermal stability, pH tolerance increased from 7.0 to 8.0, temperature tolerance increased from 60 °C to 65 °C. The magnetically immobilized papain was added to the rice bran under the condition that every gram of rice bran is submerged in 6 g of phosphate buffer solution. The magnetically immobilized papain was 0.36 mg/g, and the passivation time was 120 min. The relative activity of lipase in rice bran was 19.93%. After repeated use eight times, the relative activity of magnetically immobilized papain remained above 72%.

An in vitro study of the effect of carob (Ceratonia siliqua L.) leaf extracts on gilthead seabream (Sparus aurata L.) leucocyte activities. Antioxidant, cytotoxic and bactericidal properties.

Carob leaves, the main residues of the carob tree, were investigated as a renewable and abundant source of bioactive compounds for fish aquaculture. Aqueous and ethanolic extracts obtained from carob leaves were characterized in terms of biochemical composition, antiradical and cytotoxic effects and immunostimulant and antibacterial activities. The ethanolic extract showed higher levels of total phenolics, flavonoids and condensed tannins and higher antioxidant activity than the aqueous extract. No significant immunostimulant effects were observed on gilthead seabream (Sparus aurata) head kidney leucocytes (viability, phagocytosis and respiratory burst activities and peroxidase content) after incubation for 24 h with different extracts. Furthermore, the ethanolic extracts used at 0.5, 0.75 and 1 mg mL-1 and aqueous extracts at 1 g mL-1 had a cytotoxic effect on PLHC-1 cells. When the bactericidal activity was tested against three fish pathogenic bacteria (Vibrio harveyi, Vibrio anguillarum and Photobacterium damselae) notable activity of the different extracts was detected against P. damselae at all three concentrations. A similar effect was demonstrated against V. haryeri when ethanolic extracts were used in the same range of concentrations. This work demonstrates interesting in vitro effects of carob leaf extracts and suggests it could be used as an alternative to chemical compounds with farmed fish. The concentration and nature of the extracts were very important in terms of any positive results.

Jujube (Zizyphus lotus L.): Benefits and its effects on functional and sensory properties of sponge cake.

Jujube (Ziziphus lotus L.) fruit has multiple functional properties and represents an interesting source of bioactive compounds. The purpose of this study was to improve the functionality and the sensory properties of sponge cake enriched with Z. lotus fruit. The polyphenols and flavonoids levels in the sponge cake and its antioxidant potential increased with the addition of 0-10 g of jujube powder/100 g of wheat flour. The crumb color parameters, L* and b*, decreased with the addition of jujube powder, whereas the a* value increased. In the texture analysis, addition of jujube powder resulted in an increase of the hardness and chewiness, but the springiness was reduced. The sensory evaluation showed that supplementation of jujube powder did not manifest any undesirable organoleptic response and showed satisfactory consumer acceptability. Overall, the addition at 5% jujube powder showed the finest sensory properties of the sponge cake.

Synthesis of cost-effective magnetic nano-biocomposites mimicking peroxidase activity for remediation of dyes.

The present study describes preparation of cellulose incorporated magnetic nano-biocomposites (CNPs) by using cellulose as base material. The prepared CNPs were characterised by SEM, EDAX, TEM, XRD, and FT-IR and found to exhibit an intrinsic peroxidase-like activity with a Km and Vmax of 550 µM and 3.8 µM/ml/min, respectively. The CNPs exhibited higher pH and thermal stability compared to commercial peroxidase. These nanocomposites were able to completely remove (i) a persistent azo dye, methyl orange at a concentration of 50 ppm, within 60 min under acidic conditions (pH 3.0) and also (ii) decolourize commercial textile dye mixture under acidic conditions within 30 min. CNP-mediated degradation of dyes into simple products was further confirmed by UV-Vis and AT-IR spectroscopy The added advantage of CNPs separation after decolourization by simple magnet due to their magnetic properties and consequent reusability makes them fairy attractive system for dye remediation from environmental samples or textile industries effluents.

In Silico Identification and in Vitro Analysis of B and T-Cell Epitopes of the Black Turtle Bean (Phaseolus Vulgaris L.) Lectin.

BACKGROUND/AIMS: The incidence of lectin allergic disease is increasing in recent decades, and definitive treatment is still lacking. Identification of B and T-cell epitopes of allergen will be useful in understanding the allergen antibody responses as well as aiding in the development of new diagnostics and therapy regimens for lectin poisoning. In the current study, we mainly addressed these questions. METHODS: Three-dimensional structure of the lectin from black turtle bean (Phaseolus vulgaris L.) was modeled using the structural template of Phytohemagglutinin from P. vulgaris (PHA-E, PDB ID: 3wcs.1.A) with high identity. The B and T-cell epitopes were screened and identified by immunoinformatics and subsequently validated by ELISA, lymphocyte proliferation and cytokine profile analyses. RESULTS: Seven potential B-cell epitopes (B1 to B7) were identified by sequence and structure based methods, while three T-cell epitopes (T1 to T3) were identified by the predictions of binding score and inhibitory concentration. The epitope peptides were synthesized. Significant IgE binding capability was found in B-cell epitopes (B2, B5, B6 and B7) and T2 (a cryptic B-cell epitope). T1 and T2 induced significant lymphoproliferation, and the release of IL-4 and IL-5 cytokine confirmed the validity of T-cell epitope prediction. Abundant hydrophobic amino acids were found in B-cell epitope and T-cell epitope regions by amino acid analysis. Positively charged amino acids, such as His residue, might be more favored for B-cell epitope. CONCLUSION: The present approach can be applied for the identification of epitopes in novel allergen proteins and thus for designing diagnostics and therapies in lectin allergy.

Heating and cysteine effect on physicochemical and flavor properties of soybean peptide Maillard reaction products.

Maillard reaction products (MRPs) were obtained by using the xylose and soybean peptide system through a 2 h heating at pH of 7.6. Cysteine addition and thermal treatment at 80, 100, 120 and 140 °C were investigated via E-nose and E-tongue, free amino acids (FAA) and GC-MS analyses of MRPs. Afterwards, the combined effects were performed using the partial least square regression (PLSR). Results suggested that MRPs without cysteine addition (XSs) had stronger browning intensity, and the cysteine would be beneficial to the pH reduction with heating temperature increasing. PLSR analysis revealed that MRPs with cysteine addition heated at 140 °C (XSC-140) showed the lowest bitterness, and XS-100 had the highest umami and saltiness. Both bitter and umami FAA increased with the addition of cysteine, and more furans and nitrogen-containing compounds formed in the XSs brought caramel-like flavor, while XSCs exhibited meat-like flavor attributed to sulphides generation.

Bioactive potential and structural characterization of sulfated polysaccharides from Bullet tuna (Auxis Rochei) by-products.

The present study deals with the isolation of sulfated polysaccharides (Ps) from the Bullet tuna by-products (head, skin and bones). Results of chemical characterization revealed that Ps-bones showed the highest total sugar, uronic acid and sulfate group contents. Tuna extracted-Ps contained a mixture of neutral sugars, with high amounts of glucuronic and galacturonic acids and presented different molecular weights. The presence of sulfate groups in different Ps was confirmed by FTIR analysis. Interestingly, Ps-bones showed the highest antioxidant activity among all the extracted Ps. Moreover, results revealed that all polysaccharides displayed varying degrees of antibacterial activity. Ps-bones exhibited high and wide spectrum of activities, inhibiting the growth of all bacteria tested. Ps-bones incorporated during fillet cooking offered an excellent protection of fish fillet by avoiding pH change, color loss, lipid oxidation and spoilage. Overall, the results demonstrated that Ps could be potentially used as natural antioxidant and antibacterial agents.