Mixed Algae Research Articles

Effect of probiotics on the growth performance and survival rate of the grooved carpet shell clam seeds, Ruditapes decussatus, (Linnaeus, 1758) from the Suez Canal

The carpet shell clam, Ruditapes decussatus is one of the most popular and commercially important bivalves in Egypt. This study aimed to evaluate the addition of probiotic to fresh algae, yeast, and bacteria on growth performance and survival rates of the studied species. The experiment was performed in the Mariculture laboratory, at the Department of Marine Science, Suez Canal University, Ismailia, for 126 days from February 17th to June 21th 2018. The experiments were implanted in seven square fiberglass tanks with upwelling closed recirculating systems. Six diets were used in this experiment in addition to the control. The growth performances were determined by measurement of all biometric parameters including shell length, height, width, total weight, soft body weight and dry weight. The highest specific growth rate and growth gain of shell length, height, width and total weight were recorded in diet F (mixed algae + probiotic) while the highest SGR and GG of soft weight and dry weight were recorded in diet D (bacteria + probiotic).

Epigloea diversispora, a new possibly lichenized ascomycete from Oregon, with a key to the World species

Epigloea diversispora is newly described from a coastal mountain summit in western Oregon, U.S.A. The species has minute, shiny, jet black ascocarps appearing on a biofilm of mixed cyanobacteria and algae. The spores are diverse in both shape and septation. Immature spores are initially nonseptate and ellipsoid, then become soleiform, then 1-septate, while mature spores are 3-septate and short fusiform. Lichenization is uncertain, but the species appears to form a loosely lichenized thallus with hyphae dispersed in a partly cyanobacterial and partly algal crust on thin soil, moss, and plant detritus, over rock.

Toxic response of aquatic organisms to guide application of artemisinin sustained-release granule algaecide

In our previous study, we prepared the granules by embedding artemisinin into alginate-chitosan using microcapsule technology. These granules can release artemisinin sustainably and have a strong inhibitory effect on the growth of both single Microcystis aeruginosa and mixed algae. To safely and effectively use artemisinin sustained-release granules to control algal blooms, the ecotoxicity was studied by assessing their acute and chronic toxicity to Daphnia magna (D. magna) and Danio rerio (D. rerio), along with their antioxidant activities. The results showed that the 48-h median effective concentration (EC50) of pure artemisinin to D. magna was 24.54 mg/L and the 96-h median lethal concentration (LC50) of pure artemisinin to D. rerio was 68.08 mg/L. Both values were classified as intermediate toxicity according to the Organization for Economic Co-operation and Development (OECD). The optimal algae inhibitory concentration of artemisinin sustained-release granules (1 g/L) had low acute toxicity to both D. magna and D. rerio. The sustained-release granules had higher chronic toxicity to D. magna than to D. rerio. Partial indices of D. magna were inhibited by granules when the concentrations were larger than 0.1 g/L. Low granule concentration had an inductive effect on antioxidant enzyme activities in D. magna and D. rerio. With the increase of the exposure concentration and time, the enzyme activity presented a trend of first increasing and then decreasing, and the overall changes were significant. The change trend and range of enzyme activity indicated that the granules could cause serious oxidative stress to D. magna and D. rerio, and the changes were consistent with the results of toxicity experimentation.

The growth suppression effects of UV-C irradiation on Microcystis aeruginosa and Chlorella vulgaris under solo-culture and co-culture conditions in reclaimed water

Harmful algal blooms (HABs) are serious problems in landscape waters sourced from reclaimed water. In this study, the suppression effects of UV-C irradiation on microalgal growth were researched to find a possible preventive approach. Microcystis aeruginosa and Chlorella vulgaris were exposed to UV-C irradiation and then cultured in real reclaimed water for 7–18 d. UV-C irradiation at 50–200 mJ cm−2 could inhibit the growth of M. aeruginosa, C. vulgaris, and both microalgae in co-culture for 3–14, 1–3, and 1–5 d respectively. In addition, UV-C irradiation could cause damage to the cell integrity. At 100–200 mJ cm−2 UV-C, the proportion of microalgal membrane damage (Pmd) in M. aeruginosa cells increased rapidly to 56%–76% from day 3, whereas that in C. vulgaris cells increased to 23%–62% within 3 d. The photochemical efficiency (represented by Y value) of the irradiated groups was negatively affected immediately after UV-C irradiation and recovered gradually during the incubation. The Y value of M. aeruginosa cells began to recover from days 3 to 14, whereas that of C. vulgaris recovered much more quickly, from days 0.1 to 1. Overall, the irradiation-induced suppressive effects on algal growth correlated positively with the UV-C doses. Because M. aeruginosa was more sensitive to UV-C irradiation, UV-C irradiation not only controlled the total biomass of the mixed algae but also selectively reestablished the dominance of the nontoxic C. vulgaris.

Algal-Bacterial Symbiosis System Treating High-Load Printing and Dyeing Wastewater in Continuous-Flow Reactors under Natural Light

This study investigated the symbiotic structure relationship between mixed algae and activated sludge while treating high-load printing and dyeing wastewater under natural light. The effects of hydraulic retention time (HRT) (12 h, 16 h and 20 h) and aeration rate (0.1–0.15, 0.4–0.5 and 0.7–0.8 L/min) on algal–bacterial symbiosis (ABS) and conventional activated sludge (CAS) systems. Experimental results showed that the ABS system exhibited the best removal performance for chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total phosphorus (TP), which was increased by 12.5%, 23.1% and 10.5%, respectively, and reduced colour 80 times compared with the printing and dyeing wastewater treatment plant. Algae growth could be promoted under lower dissolved oxygen (DO), and the addition of algae could provide more DO to the ABS system. The particle size distribution of sludge in the ABS system was stable, which guaranteed a stable treatment effect. In addition, the COD and colour could be further degraded under the conditions of no external carbon source and longer HRT. It is expected that the present study will provide a foundation for the practical application of the ABS system, and new insights for the treatment of printing and dyeing wastewater.

Biosorption of Methylene Blue from Aqueous Solution Using Mixed Algae

A mixture of algae biomass (Chrysophyta, Cyanophyta, and Chlorophyte) has been investigated for its possible adsorption removal of cationic dyes (methylene blue, MB). Effect of pH (1-8), biosorbent dosage (0.2-2 g/100ml), agitated speed (100-300), particle size (1304-89μm), temperature (20-40˚C), initial dye concentration (20-300 mg/L), and sorption–desorption were investigated to assess the algal-dye sorption mechanism. Different pre-treatments, alkali, protonation, and CaCl2 have been experienced in order to enhance the adsorption capacity as well as the stability of the algal biomass. Equilibrium isotherm data were analyzed using Langmuir, Freundlich, and Temkin models. The maximum dye-sorption capacity was 26.65 mg/g at pH= 5, 250 rpm, 89μm, 25˚C, and 50 mg/L as initial concentration. Four kinetic models were tested, pseudo first order, pseudo second order, intra- particle diffusion and Elovich model. Taking into account the analysis of the (SSR and X2), the data were best fitted to Temkin isotherm model. The pseudo-second order with higher coefficient of determination fitted the data very well. Thermodynamic parameters (ΓG0, ΓH0, ΓS0, Ea and S*) at temperature ranges of 293–313 K demonstrated that biosorption is an endothermic, spontaneous reaction and higher solution temperature favors MB removal by adsorption onto algae biomass. Results show that adsorption- desorption process lasts for five cycle before losing its efficiency and the recovery efficiency increased up to 80.52%.

Influence of different diets on the growth, survival, fecundity and proximate composition of brine shrimpArtemia franciscana(Kellog, 1906)

Artemia franciscana was studied under in vitro conditions, and fed with five different microalgae species, two organic diets and one mixed diet to evaluate the nutritional profile and growth performance. The A. franciscana instar-I nauplii were stocked at a density of 100 per litre of ground borewell water with a salinity of 70 ppt in a plastic container and the culture continued for 12 days. The A. franciscana was fed with five microalgal species, such as Tetraselmis sp., Chaetoceros sp., Isochrysis sp., Thalassiosira sp. and Nannochloropsis sp., and organic diets of rice bran, soybean meal, and a mixture of Tetraselmis sp. and Chaetoceros sp. with rice bran, giving a total of eight experiments. The growth of A. franciscana was measured by length, and was observed to be the greatest (10,850 μm) in the group that was fed the mixed algae combination, and the lowest (7,290 μm) in the group that was fed Nannochloropsis sp. Among the different treatments, the highest survival value of 76% was seen in the group that was fed Chaetoceros sp. The fecundity was higher in A. franciscana that were fed with algae Chaetoceros sp., while the lower rate was observed with the group that was fed Nannochloropsis sp. Analysis of proximate composition showed increased levels in the animals fed with Chaetoceros sp. (lipid, 19.40%; eicosapentaenoic acid, 6.70 mg; docosahexaenoic acid, 10.20 mg; amino acids: proline, 2.06 μg; histidine, 0.77 μg, arginine, 0.65 μg, glycine, 0.80 μg, glutamic acid, 1.75 μg; threonine, 1.42 μg) and the mixed diet (protein, 58.59%; carbohydrate, 21.30%; amino acids: asparagine, 0.90 μg; serine, 1.65 μg; tryptophan, 1.66 μg; leucine, 1.50 μg; phenylalanine, 1.14 μg; valine, 0.66 μg). All components showed the lowest level in the diet fed with Tetraselmis species. These A. franciscana populations showed better survival, higher fecundity and biochemical profiles when cultured with microalgae Chaetoceros sp. These data are useful to improve A. franciscana culture in aquaculture to produce quality cysts and biomass, especially in feeding larvae of marine species.

Effect of limitation of iron and manganese on microalgae growth in fresh water.

Eutrophication is caused by the rapid growth of microalgae. Iron and manganese are important micronutrients for microalgae growth. However, the effect of the limitation of iron and manganese on microalgae growth in fresh water has not been well understood. In this study, natural mixed algae, Anabaena flosaquae and Scenedesmus quadricanda, were cultivated under different quotas of iron and manganese to reveal the effect of the limitation of iron and manganese on the growth of microalgae in fresh water. The results showed that the growth rate of algae is influenced more by iron than by manganese. However, the effect of manganese cannot be overlooked: when the initial manganese quota was replete, i.e. 0.6-0.8 mg l-1, manganese was able to relieve the effect of iron limitation on microalgae growth in fresh water. We further found that the microalgae showed an uptake preference for iron over manganese. Iron had a competitive effect on manganese uptake, while manganese had less impact on iron uptake by microalgae. The information obtained in the current study is useful for the provision of water quality warnings and for the control of microalgae bloom in fresh water.

Impact of food type on growth, survival and reproduction of the cyclopoid copepod Cyclopina kasignete as a potential live food in aquaculture

This study compared the efficacy of different dietary algae on the growth and reproduction of the cyclopoid copepod Cyclopina kasignete, a potential live food species for fish larvae in aquaculture. The experimental diets for the copepod consisted of three monoalgal diets (Nannochloropsis oculata, Tisochrysis lutea and dry Melosira sp.) and two mixed algae diets (T. lutea + N. oculata, T. lutea + dry Melosira sp.). The experiment was carried out for 30 days, and the population growth, survival and reproductive performance (generation time, hatching rate, life spawning times, daily offspring production, eggs per sac, lifespan and sex ratio) were used to assess the responses of C. kasignete to different food types. Population growth, survival and reproductive capacities of C. kasignete were significantly affected by the mono and binary species of algal diets. The results showed that copepods exhibited superior growth, survival and productivity when fed on fresh T. lutea, dry Melosira sp. and a mixture of both species compared to other dietary treatments. Copepods produced comparable growth, survival and productivity when fed on diatoms (dry Melosira sp.) as a single or in combination with other algae. This study indicates that cyclopoid copepod C. kasignete grow fast and have the potential to serve as a live food for aquaculture. The algae T. lutea, dry Melosira sp. and their combination are appropriate food to sustain the growth and reproduction of this copepods in mass culture as a potential live food in fish hatchery.

Development of polyurethane based anti-scratch and anti-algal coating formulation with silica-titania core-shell nanoparticles

In this present study, anti-scratch and anti-algal coating formulations were developed with silica and silica-titania core-shell nanoparticles individually in polyurethane binder. This core-shell nanoparticle was synthesized in house to utilize the mechanical property of core silica and photo-catalytic activity of thin titania shell on silica core. High mechanical property of silica improves the strength and anti-scratch property of polyurethane film whereas photo-catalytic activity of titania provides anti-algal property of the film. Silica nanoparticles were prepared through sol-gel process. TiO2 nanoparticles and core-shell nanoparticles were prepared through peptization process. The prepared nanoparticles – silica, titania and silica-titania core-shell nanoparticles were characterized by Dynamic light scattering, UV-visible spectrophotometer, scanning electron microscopy, FTIR and X-Ray Diffraction. Polyurethane coating formulations were developed with polyurethane binder, thinner and above prepared nanoparticles, where percentage of nanoparticles were kept at 4 wt% of total formulation. Dry films were casted on glass substrate with these coating formulations after applying with brush and heated at 100 °C. Scratch testing were carried out for these dried films with dry film thickness of 100 μm on glass substrate at different load from 3N to 9N. The same coating formulations were applied on small pieces of bricks for anti-algal testing against green algae and mixed algae. This core-shell formulation successfully improved the scratch resistance of coatings up-to 5N load and also provided good anti-algal property.

Mixed Culture Microalgae-Based Coconut Biodiesel as Fuel to Improve DI CI Engine Performance, Emission Characteristics

The depleting Fossil fuels reserves are caused to look into new Renewable energy sources to fulfill Diesel fuel demand in developing countries such as India. Increasing urbanization is lead to the search for new alternative sources like biodiesel. In India demand of diesel fuel in Industry and Transportation sector. To resolve all the above problems, researchers, scientists were produced biodiesel from first, second and third generation biodiesel sources. Among all the sources Algae was the most Oil rich sources. The byproducts in algae to biodiesel conversion process are most valuable than other. In the present work author tried to work in a new approach, i.e. the mixed culture algae particles are emulsified in pure Coconut biodiesel fuel by using TritonX-100 as a surfactant to prepare an emulsified fuel. This fuel sample was applied to DI CI engine to improve performance, emission characteristics. The experimental results were shown that there is the improvement in diesel engine performance; emission characteristics especially break thermal efficiency and NOx emission reduction than diesel fuel due to its clean combustion.

Understanding the stoichiometric limitation of herbivore growth: the importance of feeding and assimilation flexibilities.

Ecological stoichiometry suggests that herbivore growth is limited by phosphorus when this element in the diet is <8.6μgPmgC-1 (C:P atomic ratio >300). However, in nature, it is not necessarily related to the relative phosphorus content in diets. This may be the result of complex feeding and assimilation responses to diets. We examined these possibilities using herbivorous plankton fed mono-specific and mixed algae varying in phosphorus content of 1.6 to 8.1μgPmgC-1 . The herbivores showed a 10-fold growth rate difference among the diets. Growth rates related poorly with phosphorus content in the diets (r2 =0.07), better with P ingestion rate (r2 =0.41) and best with phosphorus assimilation rate (r2 =0.69). Inclusion of assimilation rates for carbon and fatty acids increased 7% of the explained growth variance. These results indicate that the feeding and assimilation flexibilities play pivotal roles in acquiring a deficient element and in regulating growth rate.

200 kHz Sonication of Mixed-Algae Suspension from a Eutrophic Lake: The Effect on the Caution vs. Outbreak Bloom Alert Levels

For effective ultrasonic algae removal, several studies have considered the ultrasound equipment linked factors, such as power and frequency. However, studies on the response of mixed algal cultures and associated water quality parameters to ultrasound are limited. In this lab-scale sonication, the removal of cyanobacteria at a pre-set frequency of 200 kHz on mixed algae suspensions collected from a eutrophic lake was investigated. The caution (17.5 µg/L) and outbreak (1450 µg/L) alert levels in terms of chlorophyll-a (Chl-a) concentrations of the initial samples were each sonicated for 10, 15, and 20 min, and then kept in an incubator. Fifteen minutes of sonication resulted in best removal efficiency of 0.94 and 0.77, at an ultrasonic dose of 30 kWh/m3 at the outbreak and caution level concentrations, respectively. Immediately after 15 min sonication, and after standing in the incubator for a day, chlorophyll-a removal efficiencies of 0.28 and 0.90 were achieved in the outbreak level, respectively, and the matching removal efficiencies for the caution level were 0.23 and 0.64. Even though the removal was substantial in both cases, the final 147 µg/L chlorophyll-a concentration of the outbreak, which is itself still in the outbreak level range, shows that ultrasonication is not effective to satisfactorily remove algae from a concentrated suspension. Total dissolved nitrogen and chemical oxygen demand were reduced, overall, due to sonication. However, total dissolved phosphorus of the concentrated level was increased during the treatment. Although sonication needs further replicated experimental testing in whole-lake systems, our results show that 200 kHz sonication was able to reduce chlorophyll-a concentrations in small-scale laboratory tests.

Biomarker-based H-Print quantifies the composition of mixed sympagic and pelagic algae consumed by Artemia sp.

Quantifying the importance of sea ice microalgae as a food source in Arctic ecosystems is becoming an increasingly important research objective as sea ice extent and thickness continue to reduce. Recently, the analysis of certain diatom-derived highly branched isoprenoid (HBI) lipid biomarkers has provided a means of qualitatively distinguishing between sympagic (sea ice) and pelagic algae in Arctic animals. By combining the abundances of these lipids into an HBI-fingerprint, or “H-Print”, an estimate of the relative proportions of HBIs from each algal source can also be made. Although H-Print analysis of animal tissues in the Arctic is starting to provide such information, it has not yet been established to what extent H-Prints in animals provide a true reflection of the content of their algal food source. Here it is demonstrated that the H-Print determination can yield reliable estimates of mixed sympagic/pelagic algal content both within a food source of known composition, and in a primary consumer fed on it. In doing so, the utility of the H-Print is extended towards providing quantitative estimates of the relative importance of sympagic algae to animal diet. To achieve this, a series of 5 algal samples were prepared with known %sympagic algal content ranging from 0 to 100%. Analysis of these samples led to a comparison of different regression models based upon H-Prints using 4 different combinations of individual HBIs. A linear model comprising 3 HBIs (2 sympagic and 1 pelagic) provided the most accurate estimates of the sympagic content (−1%, 50% and 101%) for samples containing 0%, 50% and 100% sympagic algae. This linear model was then used to estimate the proportion of sympagic algae in Artemia sp. (−3%, 44% and 101%) fed on the same algal mixtures in the laboratory. The similarity between H-Prints in mixed algae and Artemia sp. suggested that H-Prints were not altered substantially by grazing, and this was also confirmed by analysis of the remaining water (containing ungrazed algae and faecal pellets), where H-Prints were not significantly different from those obtained for the algae or Artemia sp. (p≥0.3). This study has extended the usefulness of the H-Print as an approach to determine ecosystem change in the future. Indeed, the ability of the H-Print to provide quantitative estimates of the importance of sympagic algae to Arctic animals is likely to result in valuable data that can be used for modelling the broader ecological impact of reducing sea ice extent.

Performance of mixed algae for treatment of slaughterhouse wastewater and microbial community analysis.

This study investigated organic matter (OM) and nutrient removal efficiency of mixed algal species from slaughterhouse wastewater (SWW) by using photo-bioreactor. For this purpose, different dilution multiples of 10, 4, and 2 were applied to the SWW, and pure wastewater was finally used for algal cultivation. OM and nutrient removal performance in an algal photo-bioreactor were severely affected by the dilution ratio. After 7days of cultivation, the highest removal percentages of total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) were 89.6, 70.2, and 96.2%, respectively. Furthermore, the changes in eukaryotic algae and cyanobacterial species in the algal photo-bioreactors were investigated using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that cyanobacterial species were more efficient than eukaryotic species in removing nutrients from the SWW. This study suggests that mixed algal photo-bioreactors could be used efficiently in the treatment of SWW.

Photosynthetic membrane-less microbial fuel cells to enhance microalgal biomass concentration

The aim of this study was to quantitatively assess the net increase in microalgal biomass concentration induced by photosynthetic microbial fuel cells (PMFC). The experiment was conducted on six lab-scale PMFC constituted by an anodic chamber simulating an anaerobic digester connected to a cathodic chamber consisting of a mixed algae consortia culture. Three PMFC were operated at closed circuit (PMFC+) whereas three PMFC were left unconnected as control (PMFC−). PMFC+ produced a higher amount of carbon dioxide as a product of the organic matter oxidation that resulted in 1.5–3 times higher biomass concentration at the cathode compartment when compared to PMFC−.

Feeding rate responses of Babylonia formosae habei (Prosobranchia: Buccinidae) larvae on cultured algae

Babylonia formosae habei is a commercially important marine gastropod species. Food particles ingested by the planktotrophic larvae of B. formosae habei can be critical in maximizing the larval growth and survival of this species. In this study, feeding rate responses of B. formosae habei larvae on cultured algae were observed using a Coulter multisizer. Variations were recorded based on the changes of different factors of influence, including varied larval stoking density, varied types of algae, varied algae concentrations and selective feeding on mixed algae cells of different types. Results of this study reveal some facts on the feeding of B. formosae habei larvae: larval stoking density has negative effect on their feeding rates; larva has a higher feeding rate on big-sized algae than small-sized algae; larva has a higher feeding rate on diatom than green algae and flagellate; feeding rate of larvae increased when fed mixed algae cells. Optimal algal concentration of the cultured algae Chlorella sp., Chaetoceros muelleri, Isochrysis zhanjiangensis and Dunaliella tertiolecta was suggested at 20 × 104, 5 × 104, 20 × 104 and 10 × 104 cells mL−1 respectively. Results of the preset study can be important in understanding feeding ecology of B. formosae habei larvae, and applicable for the aquaculture of this species.

Effect of Tetracycline Antibiotics on Performance and Microbial Community of Algal Photo-Bioreactor.

Tetracycline antibiotics have been increasingly used in medical applications and have been found in wastewater treatment plants as a result of human and industrial activities. This study investigates the combined effects of tetracycline antibiotics on the performance of an algal photo-bioreactor operated under different antibiotic concentrations in the ranges of 0.25 to 30mg/L and considers the inhibition of algal growth, carbon and nutrient removal rates, and eukaryotic and cyanobacterial algal community changes. The results indicated that increases in the concentration of tetracycline mixtures have adverse effects on the algal community and the performance of a photo-bioreactor, and the eukaryotic algae species were more sensitive to tetracycline antibiotics than were the cyanobacterial species. Cultivation tests showed that approximately 94% growth inhibition of mixed algae occurred at 30mg/L.

Effects of Fe 2+ and Fe 3+ on Algal Proliferation in a Natural Mixed Algal Colony in Algae-Rich Raw Water in Southern China

As a necessary micronutrient for algal growth, iron (Fe) has importanteffects on the physiological metabolism and enzymatic reactions of algae. There arevarious forms of iron in nature, and soluble iron exists mainly in two forms: Fe2+ andFe3+. In this study, a series of experiments were designed to compare the effects ofFe2+ and Fe3+ on the growth of natural mixed algal colonies and single-species coloniesof Scenedesmus quadricauda. The results show that Fe2+ and Fe3+ have different effectson the reproductive processes of these two algal populations. The optimal growthconcentration of both Fe2+ and Fe3+ for natural mixed algae is 0.3 mg/L; at that concentration,algal biomass reaches its peak, with values of 1.74 × 106 cells/L and 6.82× 105 cells/L for the two iron forms, respectively. At the same time, the average growthrates of these algae also reach their maximum, which are 0.3620 d–1 and 0.3398 d–1,respectively. The optimal growth concentrations of Fe2+ and Fe3+ for S. quadricaudaare about 0.4 mg/L. We propose that Fe2+ exhibits higher biological time-effectivenessthan Fe3+ for algal reproduction, and while Fe2+ and Fe3+ exhibit similar facilitation in thegrowth of both natural mixed algae and S. quadricauda, differences exist between theirfacilitation effects. The results of the study further suggest that problems involving ironuptake priority and inter-specific competition could arise during the reproductive processin mixed algal colonies.

Evaluating the Effect of Algal Extracts against Ultraviolet B-Induced Skin Damage in BALB/c Mice

Ethanol extract of mixed algae—spirogyra and ulothrix was investigated to assess the effect on some biochemical parameters in UVB irradiated mice. The dorsal-thoracic region of mice were shaved and exposed to UVB radiation for 24 h for two consecutive weeks. Five groups of ten mice each were conducted: non-irradiated control and irradiated control. Mice treated with commercial cream (S.M.) at a dose of 0.1 mg/cm 2 and mice treated with ethanol extract of mixed spirogyra and ulothrix at a dose of 0.1 mg/cm 2 or 0.2 mg/cm 2 . Topical application was performed to all treated mice groups once a day for four consecutive weeks. Results showed significant differences between treated and control groups during the whole period of experiment. The clear potentiality of the ethanol extract was detected through body and skin weight, level of total protein, Superoxide Dismutase (SOD) and Catalase (CAT) activities in skin. However, UVB irradiated mice treated with 0.2 mg/cm 2 exhibited the most significant effect when compared to control groups. That may be attributed to anti-inflammatory and anti-oxidant effects of algal extract.