Extracts Of Ulva Lactuca Research Articles

Assessment of the antibacterial and antioxidant activities of seaweed-derived extracts

In swine farming, animals develop diseases that require the use of antibiotics. In-feed antibiotics as growth promoters have been banned due to the increasing concern of antimicrobial resistance. Seaweeds offer bioactive molecules with antibacterial and antioxidant properties. The aim was to estimate the in vitro properties of seaweed extracts: Ascophyllum nodosum (AN), Palmaria palmata (PP), Ulva lactuca (UL), and 1:1 mixes (ANPP, ANUL, PPUL). Escherichia coli strains were used to test for growth inhibitory activity, and chemical-based assays were performed for antioxidant properties. The treatments were 2 (with/without Escherichia coli) × 2 (F4 + and F18 +) × 5 doses (0, 1.44, 2.87, 5.75, 11.50, and 23.0 mg/mL). Bacteria were supplemented with seaweed extracts, and growth was monitored. The antioxidant activity was assessed with 6 doses (0, 1, 50, 100, 200, 500, and 600 mg/mL) × 6 compounds using two chemical assays. Data were evaluated through SAS. The results showed that AN and UL significantly inhibited (p < 0.05) the growth of F4 + and F18 +. PP and mixes did not display an inhibition of the bacteria growth. AN, PP, UL extracts, and mixes exhibited antioxidant activities, with AN showing the strongest dose–response. Thus, AN and UL seaweed extracts reveal promising antibacterial and antioxidant effects and may be candidates for in-feed additives.

Ulvans, sulfated β-d-galactans and xyloarabinogalactan: A comparative approach to extraction, structural characterization and antioxidant activity assessment

Antioxidants can be extracted from various seaweeds as natural ingredients for use in foods, cosmetics, and pharmaceuticals. The composition and structure of polysaccharides extracted from four green seaweeds: Ulva lactuca (UL), Halimeda opuntia (HO), Caulerpa racemosa (CR) and Chaetomorpha antennina (CA) were correlated with their antioxidant activities. Crude extracts were characterized by NMR (1H and 13C), HP-SEC, HPAEC-PAD and FTIR spectroscopy. Extracted polysaccharides were assayed spectrophotometrically for their total sugar, sulfate, phenolic and protein contents. The antioxidant capacities of each fractionated polysaccharide sample were evaluated by five methods, i.e., ABTS (2,2-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]), DPPH (2,2-diphenyl-1-picrylhydrazyl radical), ferric-reducing power in FRAP (Ferric-reducing Antioxidant Power), superoxide dismutase (SOD), and the hydroxyl radical (OH) scavenging capacity assay. All polysaccharides had molecular weights (MW) under 1000 kDa, with HO having the lowest MW (<100 kDa). Polysaccharide extracts of UL (i.e., l-iduronic acid, 1,4-linked α-l-rhamnose, β-d-glucuronic acid) and CA were promising sources of antioxidants. The highest antioxidant capacity was measured in extracts from CA-2B (52.1 ± 0.9 μg/mL) using the ABTS assay, while CR-1B exhibited the highest antioxidant activity in both the FRAP (303.7 ± 8.2 μm/mL) and OH (28.4 ± 0.8%) assays. Taken together, useful insights were gained into the potential health benefits of selected green seaweed polysaccharides (i.e., ulvans, sulfated or/and pyruvylated β-d-galactans and sulfated xyloarabinogalactan) for applications in the pharmaceutical, food and biotechnology industries.

Investigation into the Phytochemical Composition, Antioxidant Properties, and In-Vitro Anti-Diabetic Efficacy of Ulva lactuca Extracts.

In this research, the chemical compositions of various extracts obtained from Ulva lactuca, a type of green seaweed collected from the Nador lagoon in the northern region of Morocco, were compared. Their antioxidant and anti-diabetic properties were also studied. Using GC-MS technology, the fatty acid content of the samples was analyzed, revealing that palmitic acid, eicosenoic acid, and linoleic acid were the most abundant unsaturated fatty acids present in all samples. The HPLC analysis indicated that sinapic acid, naringin, rutin, quercetin, cinnamic acid, salicylic acid, apigenin, flavone, and flavanone were the most prevalent phenolic compounds. The aqueous extract obtained by maceration showed high levels of polyphenols and flavonoids, with values of 379.67 ± 0.09 mg GAE/g and 212.11 ± 0.11 mg QE/g, respectively. This extract also exhibited an impressive ability to scavenge DPPH radicals, as indicated by its IC50 value of 0.095 ± 0.12 mg/mL. Additionally, the methanolic extract obtained using the Soxhlet method demonstrated antioxidant properties by preventing β-carotene discoloration, with an IC50 of 0.087 ± 0.14 mg/mL. Results from in-vitro studies showed that extracts from U. lactuca were able to significantly inhibit the enzymatic activity of α-amylase and α-glucosidase. Among the various extracts, methanolic extract (S) has been identified as the most potent inhibitor, exhibiting a statistically similar effect to that of acarbose. Furthermore, molecular docking models were used to evaluate the interaction between the primary phytochemicals found in these extracts and the human pancreatic α-amylase and α-glucosidase enzymes. These findings suggest that U. lactuca extracts contain bioactive substances that are capable of reducing enzyme activity more effectively than the commercially available drug, acarbose.

Biodiversity and suppression of wood-decaying fungi in marine environment, Alexandria, Egypt by selected natural products: Control the fungal growth/contamination

The current study investigated the biodiversity and control of wood-decaying fungi isolated from marine environment, at Alexandria, Egypt. The fungal growth was in vitro control via selected plant natural products (seaweeds and aromatic herbs). Among 45 marine fungal isolates from decaying-wood samples were detected. At 85% similarity level, 5 clusters (A, B, C, D, and E) were obtained. According to numerical classification, one strain from each cluster was identified based on the sequences of ITS-PCR. The species level because their best matched references from BLAST search were higher than 96% of similarities with ITS sequences obtained from GenBank (four Aspergillus and one Penicillium species as the most abundant isolates). Additionally, the enzymatic action of cellulase, amylase, protease, and lipase was detected by fungal isolates. The highest enzymatic degradation coefficient (EDC) was of 1.38 for lipase secreted by P. chrysogenum strain HGM3. Only three strains (A. sydowi strain HGM1, P. chrysogenum strain HGM3 and A. amstelodami strain HGM5) produced cellulase enzyme with EDC value (1.075, 1.27 and 1.08), respectively. Moreover, the methanolic extracts of Ulva lactuca and Corallina officinalis collected from the Egyptian coasts besides aromatic plant; Salvia. officinalis purchased from herbal market were qualitatively analyzed using Gas chromatographic mass spectra. Various organic crude extracts exhibited that there were different types of high and low molecular weight bioactive compounds. Most of them are basically biologically important. Thus the identification of a good number of compounds in various crude extracts of seaweeds and herbal plants might have potent ecological role.

ANTIOXIDANT AND CYTOTOXIC ACTIVITIES OF GREEN SEAWEED ULVA LACTUCA TOWARDS MCF-7 BREAST CANCER CELLS

Systematic researches for breast cancer are ran in Indonesia with its flora resources and therapeutic potentials as prospective towards cancer cells through studies concerning phytochemical contents, antioxidant activity, and cytotoxicity. The aim of this research is to obtain Ulva lactuca abundant potential that is available in Indonesia as antioxidant and anticancer towards breast cancer cell MCF-7. Ulva lactuca is extracted by maceration with solvents which are n-hexane, ethyl-acetate, and ethanol, ensuing extracts of n-hexane, ethyl-acetate and ethanol. The extracts later collected and tested through phytochemical and TLC analysis. The DPPH assay determines the extracts’ antioxidant activity as a radical scavenger and MTT assay evaluates the cytotoxicity towards MCF-7 cells. Phytochemical screening revealed secondary metabolites triterpenoids, steroids, and glycosides in Ulva lactuca. The TLC resulted that there are 11 phytochemical components. From DPPH assay, ethanol and ethyl acetate extracts of Ulva lactuca are classified to have very active antioxidant activity against DPPH free radicals, with IC50 of 3.514 ?g/mL and 33.770 ?g/mL, respectively. From MTT assay, n-hexane extract gives IC50 value of 70.496 ?g/mL, and ethyl-acetate extract gives IC50 value of 50.883 ?g/mL towards MCF-7 cells, both have moderate anticancer activity. Whereas the ethanol extract gives IC50 value of 11.920 ?g/mL on MCF-7 cells which considered to have active anticancer activity. Ethanol extract of Ulva lactuca that has a strong antioxidant and cytotoxic activity against MCF-7 cells should be further develop as an anti-breast cancer agent.

Extracts of Ulva lactuca Induce Responses against Penicillium digitatum on Oranges

Penicillium digitatum causes severe damage to postharvest and stored citrus fruits, making it necessary to seek acceptable solutions limiting environmental and sanitary impacts. The seaweed liquid extracts (SLEs) obtained from the green macroalgae Ulva lactuca have previously shown anti-fungal activities towards postharvest green mold due to P. digitatum. Moreover, treatment with aqueous and ethanolic extracts had an influence on disease incidence and lesion severity on wounded oranges “Valentia late”. Therefore, we studied the abilities of the U. lactuca extracts and chlorophyll a (as a standard) to activate defense mechanisms in oranges. The analyses showed modifications in the protein concentrations and activities of β-1,3-glucanase and peroxidase in orange tissues, with a maximum activity level reached at 72 h after treatments. It appears that the SLEs were able to fight P. digitatum infections in the absence of direct contact with the pathogen, reflecting that the induction of host resistance is also a probable mode of action. Ulva lactuca fractions are rich in chlorophyll a, polyphenols, organic acids and ulvans, which might be the key molecules involved in the defense mechanism of oranges’ albedo. The use of these natural substances could be an alternative way to control postharvest citrus rot.

Novel ZnO-biochar nanocomposites obtained by hydrothermal method in extracts of Ulva lactuca collected from Black Sea

The aqueous extract of Ulva lactuca, obtained from algae waste, has been used both as precursor for nanobiochar and source of phycocolloids, for obtaining of ZnO@C composites by hydrothermal method, through two synthesis routes, and capped ZnO nanopowders. The nanomaterials were characterized by XRD, SEM, thermal analysis, UV–vis, PL and FTIR spectroscopy. The presence of ZnO with hexagonal wurtzite structure was confirmed by XRD, while the presence of biochar and capping molecules was confirmed by FTIR spectroscopy and thermal analysis correlated with the total organic carbon determination. The band gap energy was calculated from diffuse reflectance spectra. The photocatalytic properties were tested in the degradation of Congo red azo dye under UV and visible light irradiations, the prepared zinc oxide-biochair nanocomposites demonstrating a good photocatalytic activity, superior to the pristine ZnO nanopowders obtained in similar conditions. The results confirmed a good fit with the Langmuir–Hinshelwood kinetic model. A correlation between photoluminescent and photocatalytic properties of nanomaterials was done. The properties of ZnO@C nanocomposites depended on the synthesis route were compared with those of capped and pristine ZnO samples.

Photocatalytic degradation of methyl red using seaweed mediated zinc oxide nanoparticles

In the present work, the photocatalytic potential of zinc oxide nanoparticles, prepared using extracts of Ulva lactuca (U. lactuca) and Stoechospermum marginatum (S. marginatum), has been evaluated. The effect of catalyst dosage, pH of the solution, and initial dye concentration on the degradation of methyl red under sunlight has been studied. After 180 min of solar irradiation, the S. marginatum based zinc oxide nanoparticles (Sm-ZnO) exhibited the highest degradation efficiency, 92%, at pH 7, 5 mg/L dye concentration, and 2.5 mg/mL catalyst load. Under the same conditions, U. lactuca based ZnO NP (Ul-ZnO) recorded 90% degradation. The zinc oxide nanoparticles displayed notable performance during the three degradation cycles, and the stability of the catalyst is confirmed by X-ray diffraction analysis. The dye degradation reaction followed pseudo-first-order kinetics with a rate constant of 0.0167 min−1 for Sm-ZnO NPs and 0.0155 min−1 for Ul-ZnO NPs. The treated dye solution at pH 7, 2.5 mg/mL catalyst, and 10 mg/L dye concentration has been further utilized for watering green gram plants, and the growth parameters were, with a maximum shoot and root lengths of 13.5 cm and 1.8 cm, respectively. The total chlorophyll content was 72.9 μg/mL, protein content was 62 mg/g and the carbohydrate content 446 mg/g.

Bioactive peptide production and determination of functional properties using crude water extracts of Ulva lactuca (Chlorophyta) and Sargassum crassifolium (Phaeophyceae) collected from Sri Lanka

ABSTRACT Bioactive peptides of marine macroalgae consist of various functional properties. Ulva lactuca and Sargassum crassifolium are economically important, abundant green and brown macroalgae species in Sri Lanka that are rich in bioactive and functional components. However, few studies have been conducted to identify these bioactive and functional components of seaweeds in the local context. The aim of this study was to determine the best method to generate bioactive peptides from crude water extracts of Ulva lactuca and S. crassifolium and determine the functional properties of their hydrolyzates. Crude proteins of U. lactuca (sample: deionized water, 1:4) and S. crassifolium (sample: deionized water, 1:3) were extracted with water, using previously developed method and then subjected to protein hydrolysis by using papain (65°C, pH 6.00–7.00), α-chymotrypsin (37°C, pH 7.00–8.00), elastase (25°C, pH 8.0–8.50), and protease (60°C, pH 6.50–8.50) enzymes (1:100) under their optimum pH and temperatures for 0, 3, 6, 9, 12, 24 hours followed by heat inactivation at 100°C for 15 min. The best enzyme treatment was selected by conducting 15% SDS PAGE. Accordingly, proteins treated with enzymes followed by heat inactivation at 100°C for 15 min were selected as the best after considering the SDS-PAGE images. These hydrolyzates were used to determine the antioxidant activity (DPPH scavenging activity assay) and metal chelating activity (ferrozine method). Apart from peptides generated by elastase, all protein hydrolyzates had strong antioxidant activity (p < 0.05), but hydrolyzates produced from both crude extracts using α-chymotrypsin exhibited low Fe2+ chelating activity (p < 0.05) while some showed metal releasing activity. Therefore, protein hydrolyzates produced from U. lactuca using papain, protease, and α-chymotrypsin, followed with heat inactivation showed strong antioxidant activity while having very low Fe2+ chelating activity than all protein hydrolyzates of S. crassifolium. Highlights Ulva lactuca and Sargassum crassifolium are promising marine algal resources found in Sri Lankan waters to produce bioactive peptides. Enzymatic hydrolysis can be carried out with different enzymes as papain, α-chymotrypsin, protease, and elastase enzymes under their optimum temperature and pH conditions to produce bioactive peptides. The crude peptides showed high DPPH radical scavenging activities but low Fe2+ chelating activity.

Antioxidant and antibacterial potential of Ulva lactuca species from Romanian Black Sea Coast

Abstract Green algae biomass represents an important natural resource found in marine environments which could offer new applications in the pharmaceutical and cosmeceutical industries. The paper aim was to characterize some fluid extracts of Ulva lactuca L. green macroalgae species, in the Ulvaceae family, from Romanian Black Sea Coast, through physical, chemical and biological methods. For biomedical applications it is important to study how the difference between the marine environment specific conditions, from which they are harvested, can influence the chemical composition of macroalgae. Another important aspect which could affect the bioactive green macroalgae extracts composition, is the influence of applied extraction method. In this way, the less distructive cold maceration method in different solvent concentrations was chosen, according with literature data. The extracts have been studied in order to determine total polyphenols content, total antioxidant capacity by photochemiluminescence method and antibacterial activity. The results emphasized an antioxidant and antibacterial activity of the studied macroalgae extracts, which can be improved in mixture with other bioactive natural substances, in order to obtain new pharmaceutical preparations for topical applications. The valuable obtained results offer the possibility to propose this natural resource for next studies as biomaterial in tissue engineering, wound dressing and drug delivery systems. We consider that Ulva lactuca L. green macroalgae species of Romanian Black Sea Coast, could be an important source of marine bioactive compounds with various uses in the biomedical field.

24(R, S)-Saringosterol - From artefact to a biological medical agent

Enhancing the cholesterol turnover in the brain via activation of liver x receptors can restore memory in a mouse model for Alzheimer’s disease. The edible Asian brown alga Sargassum fusiforme (Hijiki) contains high amounts of oxysterols such as (3β, 24ξ)-stigmasta-5, 28-dien-3, 24-diol (24[R, S]-saringosterol) that are a potent liver x receptor agonists. We aimed to find native European seaweed species with contents of 24(R, S)-saringosterol that are comparable to those found in Sargassum fusiforme. Additionally, we hypothesize that seasonal variations modify the amount of 24(R, S)-saringosterol in seaweeds. Sterols and oxysterols were extracted with chloroform/methanol from various seaweed species harvested in the Eastern Scheldt in different seasons between October 2016 and September 2017. Identification and quantification of the lipids was performed by gas chromatography- mass spectrometry and gas chromatography- flame ionization detection. We confirmed that brown algae Undaria pinnatifida harvested in February and Sargassum muticum harvested in October contained the highest amounts of 24(R, S)-saringosterol (32.4 ± 15.25 μg/g, mean ± S.D. and 32.95 ± 2.91 μg/g, respectively) and its precursor fucosterol (1.48 ± 0.11 mg/g), higher than Sargassum fusiforme (20.94 ± 3.00 μg/g, mean ± S.D.), while Ascophyllum nodosum and Fucus vesiculosus and Fucus serratus contained amounts of 24(R, S)-saringosterol (22.09 ± 3.45 μg/g, 18.04 ± 0.52 μg/g and 19.47 ± 9.01 μg/g, mean ± S.D., respectively) comparable to Sargassum fusiforme. In other algae only minor amounts of these sterols were observed. The green algae Ulva lactuca contained only 0.29 mg/g fucosterol and 10.3 μg/g 24 (R, S)-saringosterol, while all investigated red algae did not contain any 24(R, S)-saringosterol or fucosterol. In the Eastern Scheldt algae harvested in September/October delivered the highest yield for 24(R, S)-saringosterol, with the exception of Undaria pinnatifida that showed the highest levels in February. We showed that exposure of lipid extracts of Ulva lactuca to sunlight at room temperature or in the presence of oxygen to UV-C light lead to the quantitative conversion of fucosterol into 24(R, S)-saringosterol. Exposing pure fucosterol to UV-light did not convert any fucosterol into 24(R, S)-saringosterol underscoring the requirement of seaweed constituents in the conversion of fucosterol into 24(R, S)-saringosterol. In conclusion, we showed that brown seaweeds harvested from the Eastern Scheldt contain amounts of 24(R, S)-saringosterol comparable to Sargassum fusiforme, varying per season and showing the highest amounts in spring. In accordance with these observations the amount of 24(R, S)-saringosterol in the brown seaweeds can be modulated by light.

Pharmacological screening of some Egyptian marine algae and encapsulation of their bioactive extracts in calcium alginate beads

The pharmacological screening of some crude extracts obtained from different marine algae collected from the Mediterranean in Alexandria region in Egypt has been conducted. The methanol, butanol, and ethyl acetate extracts of Pterocladia capillacea, Ulva lactuca and Corallina mediterranea showed inhibitory activity against the growth of Lemna minor plant. The methanol and petroleum ether extracts of Ulva lactuca (VII) exhibited significant antioxidant activity 92.2 and 84.6%, respectively, in the DPPH free radical scavenging assay. The methanol and ethyl acetate extracts of Pterocladia capillacea and Corallina mediterranea showed remarkable inhibitory activity against butyrylcholinesterase. The ether extract of Pterocladia capillacea (III) and the petroleum ether extract of Ulva lactuca (VII) exhibited high antiglycation activity (69.4% and 65% with IC50 of 0.0596 ± 0.0447 mM and 0.138 ± 0.0441 mM, respectively). The ether extract of Ulva fasciata (I) potently inhibited the oxidative burst activity of phagocytes from whole blood analysis (97.99%) at a concentration of 400 µg/mL. Scanning by electron microscope (SEM) showed successful encapsulation of the bioactive algal extracts into calcium alginate beads. Tested marine macroalgae have the potential to produce bioactive metabolites with significant antifungal, phytotoxic, antioxidant, anticholinesterase, antiglycation, and immunomodulating activities.

Control of Post-harvest Citrus Green Mold using Ulva lactuca Extracts as a Source of Active Substances

Penicillium digitatum, the causal agent of citrus green mold, is responsible for 90% of post-harvest losses. Chemical fungicides are responsible for damage to human health and the environment. The exploitation of green algae as a source of pigments and carbohydrate polymers deserves a special attention. In this study, we evaluated the ability of Ulva lactuca extracts collected from Lebanon and China, to develop products for the biocontrol of post-harvest citrus green mold. Seaweed aqueous extracts (SAE), organic extracts (SOE) and chlorophylls and Ulvans fractions of Ulva lactuca are analyzed by chromatography and spectroscopy methods. The chemical compositions in functional molecules (pigments, organic acids, and monosaccharides) from extracts are compared for the samples. It was found that Lebanese Ulva lactuca is particularly rich in ulvans and other polysaccharides, while Food grade Ulva lactuca has the highest content in lipophilic molecules. Four approaches were used to evaluate their antifungal properties: inhibition of the conidia germination of P. digitatum, fungus viability, adhesion of spores to epidermal orange cells, and the disk diffusion method. For the different seaweed liquid extracts (SLEs), inhibitions of spore germination were observed between 70 and 87%. Moreover, the samples exhibited inhibitory activities towards the adhesion of P. digitatum spores. More particularly, SOE showed inhibitions of spore multiplication between 85 and 97%. According zone diamaters, Ulvan fractions showed maximum growth spore inhibitions. These findings are interesting to select extracts for safe and effective formulations dedicated to citrus fruit post harvesting protection.

Larvicidal and Inhibition Activities of Marine Algae Ulva lactuca Extracts on Culex pipiens Mosquito النشاط الإبادی الیرقی والتثبیطی لمستخلصات الطحلب البحری Ulva lactuca علی بعوضة Culex pipiens

This study aimed to investigate the larvicidal activity and inhibition effect of Sea lettuce Ulva lactuca extracts using various organic solvents (acetone, ethanol, and petroleum ether), against mosquito larvae of Culex pipiens (L.). The results revealed that all the extracts showed varied levels of larvicidal activity and inhibition effect against C. pipiens. Among them, the maximum efficacy was observed in the acetone extract which resulted in the strongest inhibition effect in the adult emergence (95%) and showed larvicidal activity (LC50=5.004 and LC90=9.76 mg/ml). Moreover, the three extracts of U. lactuca caused a reduction in the egg-laying capacity of mosquito females. Besides, the acetone extract caused the highest decrease (P < 0.05) on the mean number and hatchability of eggs produced by mosquito females. Thus, the present study suggested that using acetone, ethanol, and petroleum ether extracts of U. lactuca could be an effective method, somewhat easier, safe, and less expensive for controlling C. pipiens mosquito.

Macroalgal activity against fungal urinary tract infections: in vitro screening and evaluation study

Application of antimicrobial botanical extracts and other natural products is receiving increasing attention. The present study aimed to evaluate the antifungal activities of some macroalgae collected from Alexandria beach, Egypt for treatment of fungal urinary tract infections (UTIs). Methanol extracts of Ulva lactuca showed the highest recorded antifungal activity against Aspergillus flavus and Aspergillus niger, while Enteromorpha linza showed the highest antifungal activity against Candida tropicalis. In addition, methanol extracts of both macroalgae showed a significant urease inhibition of the corresponding fungi. Lineweaver–Burk plots indicated a reversible non-competitive mechanism for U. lactuca extract, whereas E. linza extract showed a reversible competitive inhibition. Fatty acids profile of methanol extracts of U. lactuca and E. linza showed predominance of octadecanoic acid and hexadecanoic acid (48.4% and 62.9% of total fatty acids, respectively). In addition, GC/MS results showed significant proportions of the biologically active compounds; benzodioxoles such as piperonylbutoxide, organochlorines such as p,p’-dichlorodiphenyltrichloroethane (DDT) in U. lactuca and phytosterols such as stigmastan derivatives in E. linza. The present study represents an advancement in the knowledge of the chemistry and antifungal potential of macroalgae against UTIs and offers promising trend for drug discovery from marine macroalgae.

In vitro Assessment of Antimicrobial, Antioxidant and Anticancer Activities of Some Marine Macroalgae

THE PRESENT study evaluated ethanol, methanol, ethyl acetate, hexane, chloroform and acetone extracts of five green and red seaweed species from Abu-Qir bay, Alexandria, Egypt for their antimicrobial, antioxidant activities and cytotoxicity against four cell lines. Chloroform extracts of Ulva lactuca and Ulva fasciata exhibited the highest inhibition zones against the tested pathogenic bacteria (Klebsiella pneumoniae and Proteus mirabilis) and fungi (Aspergillus flavus, Aspergillus fumingatus and Aspergillus niger) as measured by disc diffusion method. The extracts of U. lactuca and U. fasciata showed the highest antioxidant activity (IC50 6.32±0.29mg/ml and 6.61±0.27mg/ml, respectively), using DPPH (2, 2- diphenyl-1- picrylhydrazyl) scavenging method and total antioxidant capacity assay (2.13 and 1.51mg ascorbic acid equivalent/ gram dry weight, respectively). Cytotoxicity test using MTT assay showed that U. lactuca extract had strong activity against MCF-7 and Hela cell lines (IC50 10.83±1.0, 12.43±1.3μg/ml, respectively), while U. fasciata had strong activity against PC3 and HePG2 cell lines (IC50 12.99±1.2, 16.75±1.5μg/ml, respectively). As analyzed by Ultraviolet spectra, Fourier Transform Infrared spectra and Gas Chromatography Mass Spectroscopy after purification by column chromatography, the most active antimicrobial fractions in U. lactuca and U. fasciata extracts include an aromatic compound that have different active group (-C=O, phenyl ring and –OH); its molecular weight of Di-isooctyl Phthalate equals 390.56g/mol and Butylated Hydroxytoluene equals 220.356g/mol, respectively. The studied seaweeds have distinct active metabolites being a promising source of antimicrobial and antiproliferative compounds that can be used effectively in pharmaceutical drug industry.

Production of Bioactive Compounds from the Sulfated Polysaccharides Extracts of Ulva lactuca: Post-Extraction Enzymatic Hydrolysis Followed by Ion-Exchange Chromatographic Fractionation.

This paper describes a novel combined post-extraction process for obtaining bioactive compounds from the aqueous high molecular weight sulfated polysaccharides (SPs) extracts of the green algae, Ulva lactuca. After extracting the SPs, they were enzymatically hydrolyzed then the hydrolysate (V45) was fractionated into eight different molecular weight fractions (F1–F8) using ion exchange chromatography. Crude SPs together with V45 and (F1–F8) were examined for their carbohydrate, protein, and sulfate contents. In addition, their degree of polymerization (DP) was estimated and they were characterized by Fourier Transform Infrared Spectroscopy (FTIR). Fractions S1, F4, F5, and F8 showed promising antioxidant and antitumor activities in vitro. In particular, the remarkable antitumor activity of F5 on three types of cancer cell lines could be attributed to its comparable contents of protein, carbohydrate, and sulfate, in addition to its comparable contents of rhamnose and glucuronic acid, and the same for glucose and arabinose. F5 also possessed the highest Hill coefficient among the four promising fractions indicating a higher degree of cooperativity in ligand binding. Other influencing factors including DP, composition, and type of characteristic functional groups were also discussed. The implications of this work could potentially benefit the industries of food supplements and pharmaceuticals.

Probiotic dynamics during the fermentation of milk supplemented with seaweed extracts: The effect of milk constituents

Dynamics of probiotics Lactobacillus rhamnosus LGG, L. reuteri BioGaia, Bifidobacterium animalis subsp. lactis BB12 and B. longum subsp. longum BB536 were investigated during the fermentation of milk supplemented with extracts of Chondrus crispus (CC), Himanthalia elongata (HE), Laminaria ochroleuca (LO), Palmaria palmata (PP), Porphyra umbilicalis (PU), Ulva lactuca (UL) and Undaria pinnatifida (UP). After 24 h at 37 °C, LGG attained counts above 108 cfu/ml in control milk and in milk with all seaweed extracts while BioGaia only attained that level in milk with CC, HE, PP, PU and UL extracts, B12 in milk with UL and UP extracts, and BB536 in milk with CC, HE, PU and UL extracts. In physiological saline, LGG, BioGaia, BB12 and BB536 were respectively stimulated by 4, 0, 5 and 3 seaweed extracts after 24 h at 37 °C and inhibited by 1, 5, 2 and 0 seaweed extracts. Casein and whey proteins added to physiological saline neutralized inhibition caused by UL extract, increasing probiotic counts by 4–5 log cfu/ml, while lactose and citrate had no significant effect. Milk supplementation with seaweed extracts permitted attaining probiotic counts above 108 cfu/ml at the end of fermentation, a result of practical interest for the dairy industry.

Bioremediation of Nitrate Reduction Present in Leather Industries Effluent by using Marine Algae

Nitrogen occurs naturally under oxidation of nitric anhydride, N 2 O 5 and nitrates, NO 3- and also from ammonia, and ammonium ions, NH 4 +. Because of increase in human activities environmental nitrate concentrations also increased which leads to introduction of large quantities of nitrates into ground and surface waters. Agriculture is the major source of nitrate pollution because of using of nitrogen-containing fertilizers, concentrated livestock and poultry farming. Nitrates are also released from the industrial production of glass, explosives, as well as from various chemical production and separation processes. Highest reduction in nitrate content was found in benzene extract of U.lactuca 91% and very minimal reduction of 12 % was found in aqueous extract of E.intestinalis . Among all, the extracts of Ulva lactuca, Enteromorpha flexuosa fell under Category A (Good reduction), and benzene was found to be the best solvent system. Maximum reduction by powdered algae was found in C.antenina collected from Covelong and Puduchery (375 mg/l).

Green preparation of seaweed-based silver nano-liquid for cotton pathogenic fungi management.

Silver nanoparticles (Ag NPs) were synthesised using the crude ethyl acetate extracts of Ulva lactuca and evaluated their bioefficacy against two crop-damaging pathogens. The sets of lattice planes in the XRD spectrum for the Ag NPs were indexed to the 111, 200, 220 and 311 orientations and support the crystalline nature of the Ag NPs. The 3414 and 2968 cm-1 peaks were observed in crude algal thallus extract and they were characteristic of terpenoids. Further, a peak at 1389 cm-1 was observed as fatty acids. The marine macroalgae terpenoids and palmitic acid acted as reducing agent and stabiliser, respectively. The size (3 and 50 nm) and shape (spherical) of Ag NPs were recorded. The energy-dispersive X-ray spectroscopy analysis exemplified the presence of silver in its elemental nature. Moreover, U. lactuca Ag NPs were effective against two cotton phytopathogens namely Fusarium oxysporum f.sp. vasinfectum (FOV) and Xanthomonas campestris pv. malvacearum (XAM). The minimum inhibitory concentration was found to be 80.0 and 43.33 μg ml-1 against FOV and XAM, respectively. Results confirmed the anti-microbial activity of green nanoparticles against select pathogens and suggest their possible usage in developing antifungal agents for controlling destructive pathogens in a cotton agroecosystem.