Ulva Lactuca Research Articles

Transcriptomic analyses reveal increased expression of dioxygenases, monooxygenases, and other metabolizing enzymes involved in anthracene degradation in the marine alga Ulva lactuca.

To analyze the mechanisms involved in anthracene (ANT) degradation in the marine alga Ulva lactuca, total RNA was obtained from the alga cultivated without ANT and with 5 μM of ANT for 24 h, and transcriptomic analyses were performed. A de novo transcriptome was assembled, transcripts differentially expressed were selected, and those overexpressed were identified. Overexpressed transcripts potentially involved in ANT degradation were: one aromatic ring dioxygenase, three 2-oxoglutarate Fe (II) dioxygenases (2-OGDOs), and three dienelactone hydrolases that may account for anthraquinone, phthalic anhydride, salicylic acid, and phthalic acid production (pathway 1). In addition, two flavin adenine dinucleotide (FAD)-dependent monooxygenases, four cytP450 monooxygenases, two epoxide hydrolase, one hydroxyphenylpyruvic acid dioxygenase (HPPDO), and two homogentisic acid dioxygenases (HGDOs) were identified that may also participate in ANT degradation (pathway 2). Moreover, an alkane monooxygenase (alkB), two alcohol dehydrogenases, and three aldehyde dehydrogenases were identified, which may participate in linear hydrocarbon degradation (pathway 3). Furthermore, the level of transcripts encoding some of mentioned enzymes were quantified by qRT-PCR are in the alga cultivated with 5 μM of ANT for 0–48 h, and those more increased were 2-OGDO, HGDO, and alkB monooxygenase. Thus, at least three pathways for ANT and linear hydrocarbons degradation may be existed in U. lactuca. In addition, ANT metabolites were analyzed by gas chromatography and mass spectrometry (GC–MS), allowing the identification of anthraquinone, phthalic anhydride, salicylic acid, and phthalic acid, thus validating the pathway 1.

Differential growth and physiological responses of Sargassum fusiforme and epiphytic Ulva lactuca to culture densities and interspecific competition

The commercial seaweed Sargassum fusiforme is adversely affected by the increasing presence of epiphytic macroalgae, mainly Ulva species, during seawater cultivation, especially at high culture densities. In the present study, comparative studies of S. fusiforme and Ulva lactuca were carry out to examine their physiological responses to densities between monoculture and bi-culture. The results showed that, both species of algae showed significant reduction in growth when the density of the cultures (mono-and bi-culture) was increased, although U. lactuca exhibited stronger growth and photosynthetic rate than S. fusiforme in both cultures. Specifically, for S. fusiforme, its maximum quantum yield of PSII (Fv/Fm), light harvesting efficiency (α), soluble carbohydrate (SC) content, and the ratio of SC/SP were all significantly decreased by high density, whereas its nitrate reductase (NR) activity, chlorophyll a (Chl a) and soluble protein (SP) contents were significantly increased in the monoculture. High density also decreased the photosynthesis and contents of SC and SP of U. lactuca in the monoculture. Moreover, the SC contents and NR activities of both S. fusiforme and U. lactuca significantly increased whereas their SP contents decreased in the bi-culture regardless of the culture densities. U. lactuca was dominant because of its potent neighboring shading and possible allelopathic effects on S. fusiforme. Its nutrients uptake was also more rapid than that of S. fusiforme in bi-culture. The interspecific competition between the two algae became intense with the increasing density. Thus, for the maricultivation of S. fusiforme, a moderate culture density would be preferable because of the higher photosynthetic efficiency and growth rate of S. fusiforme.

Green algae to green fuels: Syngas and hydrochar production from Ulva lactuca via sub-critical water gasification

Biomass-derived energy is gaining more attention due to environmental issues and increasing energy demand. To ensure the sustainability of fossil energy substitution using biomass, diversification of sources, including marine organisms, is vital. Among various types of marine biomass discussed in the literature, the utilization of green algae Ulva lactuca for energy generation is still rare globally. Therefore, this study aims to investigate the potential of green fuel (syngas and hydrochar) production from U. lactuca (Chlorophyta) via sub-critical water gasification (SbWG). The experiments were conducted using a batch reactor at varying temperatures (300, 350, and 400 °C), reaction times (30, 60, and 90 min), and feedstock concentrations (1 and 5 wt%). The effect of temperature on gas composition was examined in detail. The results revealed that increasing temperature from 300 to 400 °C leads to an increase in the H2 content significantly from 2.21 % to 8.09 % within 90 min. However, increasing feedstock concentration from 1 to 5 wt% reduces the H2 fraction due to suppression of the steam reforming and water-gas shift reactions. Based on the ultimate analysis, the high severity of operating conditions leads to lower O/C and H/C atomic ratios owing to dehydration and decarboxylation reactions. It was confirmed by scanning electron microscope (SEM) analysis that more void structures existed in hydrochar than the algal feedstock. The SbWG process at varying temperatures and times can increase the energy contents of U. lactuca by over 47 %. Intriguingly, hydrochar obtained at 400 °C exhibited higher HHVs (i.e., 21.75–22.93 MJ kg−1) than typical low-ranked coals, making hydrochar more potential to be used as solid fuels. Finally, a reaction model was deduced, and the decomposition of U. lactuca was confirmed to follow the Arrhenius behavior.

Seaweed Extracts as an Effective Gateway in the Search for Novel Antibiofilm Agents against Staphylococcus aureus.

Treatment of biofilm-associated infections has become a major challenge in biomedical and clinical fields due to the failure of conventional treatments in controlling this highly complex and tolerant structure. Therefore, the search for novel antibiofilm agents with increased efficacy as those provided by natural products, presents an urgent need. The aim of this study was to explore extracts derived from three algae (green Ulva lactuca, brown Stypocaulon scoparium, red Pterocladiella capillacea) for their potential antibiofilm activity against Staphylococcus aureus, bacterium responsible for several acute and chronic infections. Seaweed extracts were prepared by successive maceration in various solvents (cyclohexane (CH), dichloromethane (DCM), ethyl acetate (EA), and methanol (MeOH)). The ability of the different extracts to inhibit S. aureus biofilm formation was assessed using colony-forming unit (CFU) counts method supported by epifluorescence microscopic analysis. Effects of active extracts on the biofilm growth cycle, as well as on S. aureus surface hydrophobicity were evaluated. Results revealed the ability of four extracts to significantly inhibit S. aureus biofilm formation. These findings were supported by microscopy analyses. The gradual increase in the number of adherent bacteria when the selected extracts were added at various times (t0, t2h, t4h, t6h, and t24h) revealed their potential effect on the initial adhesion and proliferation stages of S. aureus biofilm development. Interestingly, a significant reduction in the surface hydrophobicity of S. aureus treated with dichloromethane (DCM) extract derived from U. lactuca was demonstrated. These findings present new insights into the exploration of seaweeds as a valuable source of antibiofilm agents with preventive effect by inhibiting and/or delaying biofilm formation.

Optimization of Ultrasound-assisted Extraction of Ulvan from Green Seaweed Ulva lactuca

In this paper, the extraction conditions of ulvan from green seaweed Ulva lactuca by using Ultrasound-assisted extraction method were optimised. Experience was designed using Box-behnken model with experient areas as following: extraction temperature (X1: 50–90 °C), extraction time (X2: 20–40, min) and solvent-to-material ratio (X3: 50/1–70/1, v/w), objective function (Y: extraction yield) was required to get maximum value. The result showed that the optimization conditions for extraction were: extraction temperature 84.28 °C, extraction time 30.59 min with 60.21/1 (v/w) as solvent-to-material ratio, and the expected objective function Y is 22.86% based on dried seaweed weight.

Fluoxetine induces photochemistry-derived oxidative stress on Ulva lactuca

Emerging pollutants impose a high degree of stress on marine ecosystems, compromising valuable resources, the planet and human health. Pharmaceutical residues often reach marine ecosystems, and their input is directly related to human activities. Fluoxetine is an antidepressant, and one of the most prescribed selective serotonin reuptake inhibitors globally and has been detected in aquatic ecosystems in concentrations up to 40 μg L−1. The present study aims to evaluate the impact of fluoxetine ecotoxicity on the photochemistry, energy metabolism and enzyme activity of Ulva lactuca exposed to environmentally relevant concentrations (0.3, 0.6, 20, 40, and 80 μg L−1). Exogenous fluoxetine exposure induced negative impacts on U. lactuca photochemistry, namely on photosystem II antennae grouping and energy fluxes. These impacts included increased oxidative stress and elevated enzymatic activity of ascorbate peroxidase and glutathione reductase. Lipid content increased and the altered levels of key fatty acids such as hexadecadienoic (C16:2) and linoleic (C18:2) acids revealed strong correlations with fluoxetine concentrations tested. Multivariate analyses reinforced the oxidative stress and chlorophyll a fluorescence-derived traits as efficient biomarkers for future toxicology studies.

Influence of Seaweeds on the Quality of Pasta as a Plant-Based Innovative Food.

This study evaluated the effect of the incorporation of seaweed on the physicochemical and technological quality of pasta. For this purpose, enriched wheat pastas from different seaweeds (sea lettuce—Ulva lactuca, nori—Porphyra tenera, and wakame—Undaria pinnatifida) were made and compared with durum wheat pasta as a control treatment. Firstly, optimal cooking times were established by visual and instrumental methods. Then, the technological properties of weight gain (WG), swelling index (SI), cooking losses (CL), and moisture (H%) were determined. Protein and fiber analyses, texture profile analysis (TPA), and color measurements were also performed to evaluate the physicochemical properties. Overall, enriched pasta with seaweed revealed slightly shorter optimal cooking times than control pasta. Texture properties were also modified, with a lower value of hardness, and higher values of adhesiveness and resilience. However, due to the low percentages of seaweed (3%), noticeable effects were not appreciated. Moreover, color variations of enriched pasta were relevant due to the difference among seaweeds. Nonetheless, these additions increased the protein content and soluble fiber in these foods. In conclusion, pasta enriched with marine ingredients improved this nutritional profile, and the changes in technological properties did not have a major impact on the product quality.

Effect of The Inclusion of Butterfly Pea (Clitoria ternatea) and Green Sea Weed (Ulva lactuca) in The Complete Feed on The Concentration of Blood Metabolites of Male Kacang Goats

This experiment aimed to investigate the effect of including Clitoria ternatea and Ulva lactuca in the complete feed on the concentration of blood metabolites of male kacang goats. Four male kacang goats were involved in this experiment arranged following a Latin Square Design with 4 treatments and 4 periods as replication. The treatments were R0= native grass hay 60%+concentrate 40%, R1= native grass hay 30%+concentrate 40%+ Clitoria ternatea 30%, R2= native grass hay 30%+concentrate 40%+ Clitoria ternatea 15%+ Ulva lactuca 15% and R3= native grass hay 30%+ concentrate 40%+Ulva lactuca 30%. Data were analyzed using analysis of variance (ANOVA) and followed by the Duncan Multiple Range Test when significant differences were found. The results showed that feeding a complete feed containing Clitoria ternatea and Ulva lactuca did not significantly (P>0,05) affect the concentration of urea, glucose and plasm total protein in the blood of male kacang goats. Therefore, it can be concluded the inclusion of Clitoria ternatea and Ulva lactuca has no effect on the concentration of blood metabolites in male kacang goats.

Seasonal variation in the nutritional profile of Ulva lactuca produced in a land-based IMTA system

Seasonal variation in the nutritional profile of Ulva lactuca produced in a land-based IMTA system

Metal contamination of intertidal sediment and macroalgae in an area impacted by paint from abandoned boats

Metals commonly employed in boat paint (Ba, Cr, Cu, Pb, Sn and Zn) have been determined in 63-μm-fractionated intertidal sediments and in Ulva lactuca and Fucus vesiculosus sampled in the vicinity of abandoned vessels. Metal concentrations in sediment were elevated but highly variable, both between sites and amongst replicates from the same site (e.g., mean Cu ~ 100 to 1200 mg kg−1; mean Pb ~ 130 to 6900 mg kg−1) due to heterogeneous contamination by metal-rich boat paint particles. Concentrations of all metals except Zn were higher in U. lactuca than F. vesiculosus but in both species metal levels were also elevated and variable. These observations were attributed to contamination by sediment particles and physical and chemical interactions between fine, suspended or deposited paint particles and the algal surface. The latter interactions act as a means by which boat paint metals may enter the foodchain.

Assessing the potential of the unexploited Atlantic purple sea urchin, Arbacia punctulata, for the edible market

The global demand for sea urchin as seafood is currently unmet. Despite exploitation of > 40 species across the world, there is a need to identify other candidate species, especially in regions where diversification in production is sought where species are considered native. The Eastern US presents an opportunity to determine the marketability of the currently unexploited Arbacia punctulata which is naturally distributed from Massachusetts and southwards into the Gulf of Mexico. To determine whether A. punctulata had market potential, it was fed one of the following diets to determine whether the gonad tissue (uni) could be manipulated to increase gonad mass and improve gonad color for the market: dried Ulva lactuca, Salmon pellets (Skretting), Tilapia pellets (Ziegler) or an Urchinomics diet designed for sea urchins either fed for 8 weeks or 12 weeks. All of the pelleted feeds (Salmon, Tilapia and Urchinomics) increased gonad mass and altered the color. The colors of the uni were generally darker than the colors that the market would typically prefer but some individuals did exhibit colors which have been classed as acceptable to the European market. This work highlights that further research is worthwhile to assess the market potential of A. punctulata.

Energy Balance Of Third Generation Bioethanol

Global greenhouse gas emissions are constantly increasing, despite the partial replacement of fossil fuels by renewable energies. The transport sector is responsible for almost 24% of direct CO2 emissions from the combustion of fossil fuels, generating greenhouse gas emissions, highlighting the need for a greater focus of international policies to encourage the production and the use of biofuels. Bioethanol is the most consumed biofuel in the world; it is produced by fermentation from materials rich in sugar (glucose, starch, cellulose). However, the controversy around the use of first and second generation have forced the transition to the third generation based on marine and freshwater algae; the latter have the advantage of being abundant, even invasive, easy to cultivate with good energy potential. This study proposes a life cycle analysis (LCA) of bioethanol production from the macro algae Ulva Lactuca, it was carried out after the introduction of several data into the SimPro8.1 software (e.g. quantity of water, consumed electricity, used chemicals) using the Impact 2002+ methodology. The results show a positive energy balance reflecting high-energy efficiency since the system produces about 1.44 times the energy consumed.

Effects of Glyphosate-Based Herbicide on Primary Production and Physiological Fitness of the Macroalgae Ulva lactuca

The use of glyphosate-based herbicides (GBHs) worldwide has increased exponentially over the last two decades increasing the environmental risk to marine and coastal habitats. The present study investigated the effects of GBHs at environmentally relevant concentrations (0, 10, 50, 100, 250, and 500 μg·L−1) on the physiology and biochemistry (photosynthesis, pigment, and lipid composition, antioxidative systems and energy balance) of Ulva lactuca, a cosmopolitan marine macroalgae species. Although GBHs cause deleterious effects such as the inhibition of photosynthetic activity, particularly at 250 μg·L−1, due to the impairment of the electron transport in the chloroplasts, these changes are almost completely reverted at the highest concentration (500 μg·L−1). This could be related to the induction of tolerance mechanisms at a certain threshold or tipping point. While no changes occurred in the energy balance, an increase in the pigment antheraxanthin is observed jointly with an increase in ascorbate peroxidase activity. These mechanisms might have contributed to protecting thylakoids against excess radiation and the increase in reactive oxygen species, associated with stress conditions, as no increase in lipid peroxidation products was observed. Furthermore, changes in the fatty acids profile, usually attributed to the induction of plant stress response mechanisms, demonstrated the high resilience of this macroalgae. Notably, the application of bio-optical tools in ecotoxicology, such as pulse amplitude modulated (PAM) fluorometry and laser-induced fluorescence (LIF), allowed separation of the control samples and those treated by GBHs in different concentrations with a high degree of accuracy, with PAM more accurate in identifying the different treatments.

Uptake and photoinduced degradation of phthalic acid esters (PAEs) in Ulva lactuca highlight its potential application in environmental bioremediation

The bioaccumulation of phthalates was studied in fragments of Ulva lactuca exposed for a maximum of 31 days at different concentrations of a solution of six phthalic acid esters (PAEs). The algal matrix showed rapid uptake since the first sampling, which increased over the time of the experimental period, at the end of which seaweed’s bioaccumulation potential was also evaluated. After the uptake, the algal matrix was subjected to UV irradiation in order to verify the removal of the phthalates. PAEs with higher octanol–water partition coefficients (logKow) and molecular weights were preferentially uptaken by U. lactuca in all the exposure experiments. It was observed that both accumulation (biota-sediment accumulation factor (log10BSAF) ranging from 3.75 to 4.02) and photodegradation (higher than 70% removal for all phthalates in 8 h) are more efficient at lower concentration levels. These results suggest the potential use of the algal matrices for environmental bioremediation, in order to mitigate the impact of pollution from ubiquitous pollutants such as PAEs.

Optimisation of Vitamin B12 Extraction from Green Edible Seaweed (Ulva lactuca) by Applying the Central Composite Design.

Vitamin B12, only found naturally in animal-based foods, is essential for brain functions and various chemical reactions in the human body. Insufficient vitamin B12 leads to vitamin B12 deficiency, common among strict vegetarians due to their limited intake of animal-based foods. Nevertheless, extensive studies have demonstrated that macroalgae, specifically the Ulva lactuca species, are rich in vitamin B12 and could be further exploited in future dietary applications. In the current study, the ideal extraction method of vitamin B12 from dried U. lactuca was developed and optimised to achieve the maximum vitamin B12 yield. The effects of several extraction parameters, including the solvent-to-solvent, methanol:water (MeOH:H2O), and solute-to-solvent ratios, and pH on the total vitamin B12 content were analysed through a two-level factorial and central composite design. The highest vitamin B12 content, particularly cyanocobalamin (CN-Cbl), was recovered through the ultrasonic-assisted extraction (UAE) of oven-dried U. lactuca at 3 g:60 mL of solute-to-solvent and 25:75% of MeOH to H2O ratios at pH 4. The extraction of CN-Cbl from oven-dried U. lactuca that employed the UAE method has elevated CN-Cbl content recovery compared to other extraction methods.

Burn wound healing activity of ethanol extract gel of Green Algae (Ulva lactuca L) in mice

Recently, burn injuries have become a major cause of morbidity and mortality in low-middle-income countries. Burn injuries are tissue loss caused by contact with heat sources such as hot water, fire, chemicals, electricity, and radiation. According to the WHO Global Burden Disease, in 2017 an estimated 180.000 people died from burn injuries. Ethanol extract of green algae (EEGA) contains compounds that potentially heal burn injuries. The research was conducted to obtain a gel formulation from EEGA and test its burn wound healing properties in mice ( Mus musculus ). Forty-five mice were divided into five groups: I (negative control), II (treated with gel base), III (positive control, Bioplacenton gel), IV (5% EEGA gel), and V (10% EEGA gel). Wound diameters and description scores were observed every fourth, seventh, and fourteenth day, and the derived data were analyzed in the SPSS program with the one-way analysis of variance (ANOVA) and least significance difference (LSD) test. The results indicate that EEGA can be formulated into gels with physical properties compliant with the requirements of the dosage form. Further, it was found that Groups IV and V showed significant reductions in wound description scores and diameters (p<0.05). In conclusion, gels containing 5% and 10% EEGA possess burn wound healing properties.

Diet of the land vegetable Lactuca sativa as an alternative to macroalgae for the growth of juvenile the sea urchin Loxechinus albus in northern Chile

The sea urchin Loxechinus albus is of great commercial value due to its nutritional content. The main diet of the urchin in the north of Chile in its natural habitat is the macroalgae Ulva lactuca. This work evaluated the growth of L. albus juvenile fed diets based on vegetable lettuce Lactuca sativa and macroalgae Ulva sp. Ingestion, growth, survival, and proximal analysis of the diets were registered for 13 weeks. At the end of the experience (90 days), no mortality and greater consumption of L. sativa were observed. In the proximal analysis, L. sativa presented the highest percentage (lipids, proteins, ashes, carotenoids, chlorophyll). The greatest growth and weight gain were observed with the Ulva sp. diet. Finally, the incorporation of L. sativa in the diets of urchins would imply a supplement of minerals and carotenoids, so we propose the addition of this lettuce as a nutritional supplement during the first stage of the cultivation of the L. albus.

Effect on Broiler Production Performance and Meat Quality of Feeding Ulva lactuca Supplemented with Carbohydrases.

Simple SummaryMacroalgae have been increasingly exploited worldwide for feed, food and biofuel applications, due to their nutritive and bioactive compounds. Green seaweeds belonging to the genus Ulva have high growth rates, which makes them suitable for being cultured in sustainable algae production, such as an integrated multi-trophic aquaculture system. This is expected to increase the use of Ulva sp. as an alternative source to conventional feedstuffs (e.g., cereals and soybean meal) for poultry. The objective of the current study was to assess if the incorporation of 15% Ulva lactuca in broiler chickens’ diet, combined or not with carbohydrate-active enzymes, would enhance meat nutritional quality without compromising animal growth performance. Overall, U. lactuca led to an accumulation of antioxidant carotenoids, n-3 PUFA and macrominerals, including magnesium, potassium and phosphorus, in the breast muscle, with likely health benefits, without significantly impairing growth performance. The supplementation of macroalgae with a recombinant ulvan lyase reduced ileal viscosity with possible beneficial effects on broiler digestibility. Although dietary U. lactuca showed potential to increase meat quality, it reduced meat overall acceptability, which suggests the use of a lower algae inclusion level to prevent a negative meat sensory perception for consumers.The aim of the study was to test if feeding 15% U. lactuca to broilers, alone or combined with carbohydrases, enhanced meat nutritional quality, without compromising growth performance. One hundred and twenty 22-day-old broilers were allocated to the following diets and replicated 10 times for 14 days: (1) maize and soy-based diet (control); (2) control with 15% U. lactuca (UL); (3) UL diet with 0.005% commercial carbohydrase mixture (ULC); and (4) UL diet with 0.01% ulvan lyase (ULE). Final body weight and average daily gain decreased (p < 0.050) with the ULE diet compared with the control, but no significant differences were found for the other diets. The intestinal viscosity increased (p < 0.001) with all alga diets but was lowered (p < 0.050) in the ileum with the ULE diet, relative to UL and ULC diets. Meat lightness and redness values, off-flavours, and total carotenoids increased (p < 0.001), while yellow values, tenderness, juiciness, overall acceptability, α- and γ-tocopherol, and total lipids decreased (p < 0.001) with alga diets. The n-3 polyunsaturated fatty acids (PUFA) increased (p < 0.050), and the n-6/n-3 PUFA ratio decreased (p < 0.001) with the ULE diet. Total minerals in meat increased (p < 0.001) with alga diets, conversely to sodium and zinc (p < 0.001). Feeding 15% of U. lactuca to broilers did not impair growth but increased meat nutritional value through the accumulation of health-promoting antioxidant carotenoids, n-3 PUFA and total minerals, although reducing overall meat acceptability.

Potential of Ulvan Polysaccharide from Ulva lactuca as Antifungal Against Some Foodborne Fungi Isolated from Spoiled Tomato Sauce Cans

ABSTRACT The extracts from Ulva lactuca have biological and nutritional values. The protein was 48.7 mg/g dry wt, soluble carbohydrate 43.9 mg/g dry wt, insoluble carbohydrate was 223 mg/g dry wt and lipid was 18.3 mg/g dry wt. Maximum antifungal activities of U. lactuca were observed with ulvan extract. The most predominant fungi in spoiled tomato sauce cans were Aspergillus flavus (33.6%), Rhizopus stolonifer (26.8%), and Fusarium oxysporium (22.3%). The minimal fungicidal inhibition concentration of ulvan extract against A. flavus and R. stolonifer were 10 mM and 15 mM, respectively. The colony deactivation of A. flavus and R. stolonifer by ulvan extract occurred was 91% and 89%, respectively, at 25 C after 72 h, but the deactivation occurred at 100% after 24 h at 4°C. Results affirmed the damaging effect on both tested fungal spores’ walls and intercellular components. So, ulvan polysaccharide can be used as a natural preservative for raw or processed tomato sauce to increase its shelf life.

Utilization of cellulose and ulvan from the green seaweed Ulva lactuca in the development of composite edible films with natural antioxidant properties

Cellulose and ulvan were extracted sequentially from the green seaweed Ulva lactuca and were used for the development of edible films with natural antioxidant properties. The composite films were composed of cellulose, polyvinyl alcohol, glycerol as plasticizer and different ulvan concentrations. The interaction between ulvan and film components was described by FT-IR analysis, which confirmed the formation of hydrogen bonding interactions between cellulose and ulvan. The incorporation of ulvan into the cellulose films markedly increased film thickness, water solubility and water vapor permeability, whereas the oxygen permeability was decreased. Additionally, the composite films showed good barrier properties against UV and visible light. The moisture sorption of the films was modelized using Peleg's model which exhibited a satisfactory fitting to the experimental data. The thermal stability was markedly enhanced in the presence of high concentration of ulvan. Furthermore, the incorporation of ulvan to cellulose films enhanced its antioxidant properties as measured by total antioxidant assay (TAC), ferric reducing antioxidant power (FRAP), hydroxyl radical scavenging activity (HRSA) and iron chelating activity (ICA). The use of water and 3% acetic acid as food simulants indicated that the FRAP was higher in case of water, while the opposite trend was observed for the HRSA and ICA. Overall, the developed cellulose/ulvan films could have potential uses in food packaging to promote the shelf-life of different food products.