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In order to create new value in biomass production using sterile Ulva with high production efficiency, we selected sterile Ulva with high culture stability from the coast of Imari City in Japan and investigated the conditions for generating high concentrations of dissolved oxygen through photosynthesis using the sterile Ulva. In the cultivation of sterile Ulva, we investigated the conditions for generating high concentrations of dissolved oxygen (DO) by controlling conditions such as aeration, NO3‐N concentration, and population density. As a result, we found that under the cultivation control conditions we found, DO reached about 3.8 times the saturation concentration after 3 h. It was found that this high level of DO can be maintained if the supersaturated DO seawater obtained here is properly sealed. Seawater containing high levels of DO is essential for the cultivation of oysters and shellfish, which also prefer a growth temperature of 20°C−25°C. Therefore, from the perspective of creating new value in biomass production, we developed a new system for simultaneously cultivating sterile Ulva and cultivating oysters. [ABSTRACT FROM AUTHOR]

Ulva lactuca, a green seaweed, may be an alternative source of nutrients and bioactive compounds for weaned piglets. However, it has a recalcitrant cell wall rich in a sulphated polysaccharide – ulvan – that is indigestible to monogastrics. The objective of this study was to evaluate the effect of dietary incorporation of 7% U. lactuca, combined with carbohydrases supplementation (commercial carbohydrase mixture or recombinant ulvan lyase), on growth performance, nutrient digestibility and gut health parameters (morphology and microbiota) of weaned piglets. The experiment was conducted over 14 days using 40 weaned piglets randomly allocated to one of four experimental diets: a control diet based on wheat–maize–soybean meal, a diet with 7% U. lactuca replacing the control diet (UL), a diet with UL supplemented with 0.005% Rovabio® Excel AP, and a diet with UL supplemented with 0.01% of a recombinant ulvan lyase. The dietary treatments had no major effects on growth performance, nitrogen balance and gut content variables, as well as histological measurements. Contrarily, dry matter and organic matter digestibility decreased with dietary seaweed inclusion, while hemicellulose digestibility increased, suggesting a high fermentability of this cell wall fraction independently of carbohydrases supplementation. Some beneficial microbial populations increased as a consequence of enzymatic supplementation (e.g., Prevotella), while seaweed diets as a whole led to an increased abundance of Shuttleworthia, Anaeroplasma and Lachnospiraceae_NK3A20_group, all related with a healthier gut. It also decreased Lactobacillus when compared to controls, which is possibly related to increased bioavailability of seaweed zinc. This study indicates that, under these experimental conditions, up to 7% dietary U. lactuca has no detrimental effect on piglet growth, despite decreasing acid detergent fibre digestibility. Carbohydrases supplementation of Ulva diets is not required at this incorporation level. [ABSTRACT FROM AUTHOR]

This study evaluated the biological characteristics of seaweeds Turbinaria ornata, Ulva lactuca, and Gracilaria crassa. Among the seaweeds tested, ethyl acetate extract of Ulva lactuca exhibited the highest antibacterial activity against Salmonella enterica, Staphylococcus aureus, and Pseudomonas aeruginosa. The phytochemical analysis of ULME and ULEA showed the presence of most of the tested phytochemicals, whereas only amino acids, tannins, glycosides, and carbohydrates were detected by ULHE. The DPPH scavenging property of U. lactuca exerted the maximum antioxidant property of 62.54% (ULME), 75.64% (ULEA), and 39.55% (ULHE), whereas the alpha amylase inhibitory property (µg/mL) of ULME, ULEA, and ULHE was, respectively, 80.99, 51.15, and 49.23. ULME, ULEA, and ULHE exhibited the greatest alpha-glucosidase inhibition, with IC50 values (g/mL) of 116.12, 45.59, and 170.10 correspondingly. ULEA also showed potent mosquito-larvicidal effects against Aedes aegypti larvae with the maximum lethal concentration values with LC50 and LC90 values (mg/mL) being 11.55 and 65.97, respectively. FTIR analysis of ULME, ULHE, and ULEA were found to have various functional groups, including alkanes, carboxylic acids, alkenes, alkynes, aldehydes, amides and alkanes, ketones, and aromatics, while HPLC revealed a strong peak at 4.760 retention time. In conclusion, Ulva lactuca, particularly its ethyl acetate extract, demonstrates significant antibacterial, antioxidant, and enzyme-inhibitory properties, highlighting its therapeutic and biotechnological potential. Its diverse phytochemicals and effective mosquito-larvicidal activity further support its broad application prospects. [ABSTRACT FROM AUTHOR]

The global ocean is undergoing gradual acidification and eutrophication which may have significant impacts on macroalgal communities. However, little is known regarding the interactive effects of ocean acidification (OA) and nitrate on Ulva lactuca, a primary producer widely distributed in coastal waters. This study focuses on the possible interactive effects of OA and elevated nitrate levels on physiological parameters of U. lactuca. Higher nitrate levels may increase growth, photosynthesis, respiration, pigment synthesis, Fv/Fm and Effective Quantum Yield, whereas CO2 enrichment may result in a reduction in photosynthesis, pigment content, Fv/Fm and Effective Quantum Yield. Higher nitrate levels increase NO3- uptake rate and nitrate reductase activity, which are further amplified by elevated CO2 levels. However, the stimulation of high nitrate towards pigment synthesis and photosynthesis is negatively affected by elevated CO2 levels. Our results suggest that U. lactuca could potentially increase its biomass in coastal eutrophic waters, and OA in the future is not expected to promote the growth of U. lactuca, but it can enhance its potential biofiltration to remove nitrate from coastal ecosystems. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tea is a fairly popular drink among the public. Ulva lactuca seaweed has the potential to be used as raw material for making tea, because of its active compounds. Tea from seaweed has shortcomings in fishy aroma and taste, to reduce the fishy odor, soaking is done using activated charcoal. The purpose of this study was to determine the best concentration of activated charcoal that can absorb fishy aroma in U. lactuca tea, as well as to know the characteristics (water content, ash content, extract in water, pH, total phenol, and hedonic). The experimental design of this research uses RAL with 4 levels of treatment and 2 times replication. The treatment levels of U. lactuca tea include AA1: 0% (control), AA2: 10% activated charcoal, AA3: 20% activated charcoal, and AA4: 30% activated charcoal. The data analysis method used descriptive analysis on water content, ash content, extract content in water, pH, total phenol, and Kruskal-Wallis analysis on the hedonic test. The results of this study showed that the best concentration of active charcoal in the U. lactuca tea soaking process is with 30% active charcoal soaking, hedonic test results on color parameters: 4.20; aroma: 3.83; flavor: 3.43; water content value: 13.50%; ash content value: 15.49%; extract value in water: 24.8%; pH value: 6.48; and total phenol value: 687.30 mg/g. [ABSTRACT FROM AUTHOR]

Ulva is an unutilized green seaweed that grows in the intertidal zone around the coast of Java Island, Indonesia. In this study, U. lactuca samples collected from three regions in south of Java Island (Cihara, Surade, and Tepus) were studied in terms of their chemical composition, physical properties and its bioactivity, to determine the best regions for establishing seaweed industries. The chemical characteristics differed significantly among different regions, where the seaweed from Tepus, Surade and Cihara had the highest content of protein (22.93%), carbohydrate (61.58%), and mineral (28.72%), respectively. The amino acids were dominated with L-aspartic acid and L-glutamic acid. All U. lactuca samples contained abundant pigments, such as chlorophylls and carotenoids, especially samples from Tepus. The highest content of crude ulvan was found in Surade seaweed (26.9%). Chemical and physical analyses showed the presence of S = O and C–O–S functional groups in ulvan, a sulfated polysaccharide unique to Ulva sp., with thermal degradation up to 220 °C. Crude ulvan from Surade and Tepus seaweed exhibited bioactivity to support proliferation of fibroblast cells at 100 and 1000 ppm, respectively. Based on the properties of U. lactuca, Tepus and Surade were identified as potential sites to establish aquaculture and/or processing industries. [ABSTRACT FROM AUTHOR]

Abstract The pollution by heavy metals in coastal waters has gradually intensified due to industrial development. In this study, physiological responses of Ulva lactuca, one of the most common green seaweeds with important ecological and economic value in the global intertidal zone, to acute copper stress were investigated. Results showed that an increase in copper ions concentration significantly inhibited photosynthetic activity and inorganic nitrogen utilization by U. lactuca but, increased its respiration. Copper stress limited the activity and gene expression of enzymes related to carbon and nitrogen assimilation of U. lactuca. Under moderate copper stress, U. lactuca had higher soluble carbohydrate and soluble protein contents, whereas under high copper stress, these components decreased sharply. Copper stress increased malonaldehyde content, and relative electrical conductivity in U. lactuca, but changes in antioxidant enzyme activities were not significant and even slightly decreased. Moreover, the contents of 8-hydroxy-deoxyguanosine and polyADP ribose polymerase in U. lactuca increased by high Cu2+ concentration culture, indicating that oxidative damage caused by high Cu2+ level involved its DNA damage and interfered with DNA repair in the alga. Copper stress seemed to be more damaging to the carbon assimilation process of U. lactuca, resulting in weakened resistance to copper stress and lower growth rate. This reflected the threat of coastal high copper stress to intertidal biodiversity. This provided ecological reference for the assessment of offshore heavy metal pollution represented by copper.

To explore the extraction process of mycosporine amino acids (MAAs) and the antibacterial mechanism of Vibrio parahaemolyticus, the effects of liquid-solid ratio, extraction temperature and extraction time on the yield of MAAs were analyzed by single factor and response surface optimization tests, and MAAs were isolated and identified by silica gel column chromatography, HPLC and ESI-MS. The antibacterial mechanism of MAAs against Vibrio parahaemolyticus was analyzed by scanning and fluorescence microscopy to observe the leakage of intracellular nucleic acids and proteins, and DNA decomposition. The results showed that the optimal extraction parameters of MAAs of Ulva lactuca was liquid-solid ratio of 25 mL/g, extraction temperature of 40 ℃ and extraction time of 118 min, and the yield of MAAs was 179.34±3.91 mg/g. MAAs significantly destroyed the cell membrane of Vibrio parahaemolyticus, causing the leakage of nucleic acid and proteins, and promoting the breakdown of DNA in the bacteria. MAAs were isolated by silica gel column chromatography to obtain two fractions, and the fraction H2 was identified as shinorine, and the content in Ulva lactuca dry powder could reach 10.32 mg/g. This study provides a technical reference for the preparation of MAAs of Ulva lactuca and the biological control of Vibrio parahaemolyticus.

Integration of biological activities of the algal and bacterial communities enhances the bioremediation potency of aquaculture systems. The effects of nitrogen removal mediated by Ulva lactuca on the bacterial community structure and the abundance of nitrogen cycle functional genes were investigated using an integrated multi-trophic aquaculture (IMTA) system mainly composed of sea cucumber (Stichopus japonicus), shrimp (Penaeus japonicus), and crab (Portunus trituberculatus). The experimental treatments were separated into two groups: control group (C: without U. lactuca) and algae treatment (A: with U. lactuca). Microbial diversity and abundance indexes, including the Sobs, Shannon, Ace, and Chao1 indexes, were higher in the U. lactuca treatment group in both water and sediment. Flavobacteriaceae and Rhodobacteraceae were the dominant families in both the U. lactuca and control treatment groups in October and November, respectively. In sediment, Bacillaceae was the dominant family in the U. lactuca treatment group throughout the experimental period, whereas Desulfocapsaceae was the dominant family in the control group in October and November. Moreover, the nitrogen cycle functional genes nifH, amoA, nxrB, norB, and nrfA were more abundant in the U. lactuca treatment group than in the control group. Results of water quality and its correlation with bacterial community were comprehensively investigated, revealing that U. lactuca influenced the bacterial community structure and nitrogen cycle by increasing DO in the IMTA system. In conclusion, U. lactuca co-cultured in an IMTA system could represent a novel approach for enhancing nitrogen removal, based on the interaction between the algal and bacterial communities. [ABSTRACT FROM AUTHOR]

Nori is a dried edible seaweed sheet made from Porphyra, a genus of red algae that thrivesprimarily in subtropical waters. Nori-like products have been developed from tropical seaweed species but they are still considered undesirable due to their astringent taste and lower protein content compared to the original nori. This investigation aimed to produce a nori-like product by utilizing a combination of locally sourced seaweeds, Ulva lactuca and Gracilaria changii, with the addition of anchovy flour to enhance its protein content. To obtain the optimal formulation of the product, we employed a design expert software application to analyze sensory data collected from a hedonic scale assessment involving 25 trained panelists. We evaluated sensory characteristics, including appearance, aroma, texture, taste, and overall satisfaction. Additionally, we considered parameters such as crispness and colour to determine the nori-like product quality. The best-selected product, determined through sensory evaluation, underwent further analysis of its proximate and amino acids profile, as well as mineral content. The results were compared to those of commercial nori from Porphyra. The highest-quality product was found to be the nori-like product with a formula consisting of 25.40% Ulva lactuca, 7.98% Gracilaria changii, 1.50% glycerin, 4.12% anchovy powder and the remainder water. [ABSTRACT FROM AUTHOR]

Ulva lactuca is a macroalgae that contains high nutritional values. The heavy metal contaminants in natural Ulva lactuca needs to be eliminated or decreased using natural agent. The aim of this research was to determine the bioaccumulation of Pb, Cd, Hg, and the impact on liver and gastrointestinal function. Parameters of this research were Hepatosomatic Index (HSI), SGPT levels, SGOT levels, bioaccumulation Pb, Cd, Hg, and histological structure of liver and small intestine. Besides that, the progression of body weight was observed. Twelve female Wistar rats (Rattus norvegicus Berkenhout, 1769) were randomly assigned to three groups: Control, NU (treated with natural Ulva lactuca), and DU (treated with heavy metal decontaminated Ulva lactuca using Averrhoa bilimbi juice). Treatment was carried out orally at a dose of 1000 mg/Kg BW/day for 30 days. Histological structure of rat's liver and small intestine were prepared after necropsy at the end of this research. Based on results, it can be concluded that there were no significant differences observed in HSI, SGPT, and SGOT levels among the groups. However, there was a tendency for an increase in total bilirubin levels in the decontaminated Ulva lactuca group. Both natural and heavy metal decontaminated Ulva lactuca showed histological damage on liver and small intestine. Bioaccumulation of Cd and Hg in the liver and gastrointestinal tract of rats after consuming decontaminated Ulva lactuca was lower than the natural Ulva lactuca group, but need more observations. [ABSTRACT FROM AUTHOR]

Algae are photosynthetic organisms which can be cultivated and produced in photo-bioreactors; therefore, choosing the design parameters and conditions are critical in order to achieve high efficiency and maximum productivity. Algae are of interest to biochemical industries because of their diverse species. This project seeks to build a photo-bioreactor tank to maximize Ulva lactuca non-seasonal survival to produce biodiesel from its biomass. The chosen design was because of the ease of monitoring, and the tank design effectively kept Ulva lactuca alive and fresh. Biodiesel was accomplished using an alkaline esterification for 50 g of dry mass of Ulva lactuca giving a relatively limited yield of approximate 13% of Ulva lactuca oil (4 ml) that was converted to (0.5 ml) biodiesel, compared with other oils such as soybean (42%), corn oil (60%) and cooked corn oil (40%). The yield of Ulva lactuca oil was statistically significantly lower than the other three types of oil (p-value = 0.0032). However, this project still aids in the economics of Jordan, as Ulva lactuca is grown locally in the Gulf of Aqaba. Ulva lactuca investment is worth considering because of its natural exposure, high yield, low cost, reduced algae contamination risk, and space requirements. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian Ocean University is the property of Journal of Dalian Ocean University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To study the effect of ulvans and oligo-ulvans on the stimulation of growth in Arabidopsis thaliana, extracts of Chilean U. lactuca were prepared in water at pH = 7 and pH = 4, and ulvans were purified. The yield of ulvans was 16% of dry weight in both extracts and molecular weights were 115 kDa in extract at pH = 7 and 70 kDa in extract at pH = 4. Purified ulvans were analyzed by FT-IR and H1 RMN showing carboxyl and sulfate groups and they are constituted by rhamnose, rhamnose-3S, xylose and glucuronic acid, but not by iduronic acid. The antioxidant capacities of U. lactuca extracts were determined showing that ulvans are the main contributors to antioxidant capacity whereas ascorbate, glutathione, and phenolic compounds exert a minor contribution. To analyze whether ulvans and oligo-ulvans can stimulate plant growth, oligo-ulvans were prepared by acid hydrolysis and they were sprayed on A. thaliana leaves. Ulvans and oligo-ulvans increased A. thaliana biomass, fresh and dry weight, rosette diameter, number of leaves, and length of the main root, mainly oligo-ulvans. To determine whether the increase in plant growth may involve an enhanced basal metabolism and cell division, the level of transcripts encoding enzymes involved in C, N, and S assimilation, and proteins controlling cell cycle were analyzed. The expression of the latter genes was increased, mainly in response to oligo-ulvans. Thus, ulvans and oligo-ulvans stimulate growth of A. thaliana plants probably by increasing basal metabolism and cell division. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Atlantic wakame (AW) and sea lettuce (SL) are edible seaweeds commonly produced in Asia and Europe, typically consumed as fresh or dried biomass. Because of the short shelf life, developing new post-harvest treatments, such as the extraction of bioactive compounds, is essential for establishing reliable macroalgae supply chains for food applications. This study aims to develop a sustainable and functional seaweed-based food ingredient rich in bioactive compounds for functional food applications. The results indicated that ultrasound-assisted extraction using 70% ethanol for 10 min was optimal for both SL (410±23 mg of gallic acid equivalent [GAE] per kg) and AW (666±63 mg GAE/kg). Both extracts exhibited chemical antioxidant activity and inhibited the protection of human plasma against chemically induced oxidation. SL extract did not exhibit free radical scavenging activity (DPPH). Importantly, no cytotoxicity (IC50>250 µg/mL) was observed in human-derived THP-1, HUVEC, HT-29, and HepG2 cell lines, ensuring the relative safety of these extracts for potential food technology applications. AW and SL extracts (100 µg/mL) reduced intracellular reactive oxygen species generation in lipopolysaccharide (LPS)-challenged THP-1 cells by 66% and 30%, respectively, highlighting the higher antioxidant activity of AW extract. AW and SL extracts did not modulate TNF-α and IL-6 secretion to show anti-inflammatory activity. Gummies infused with AW and SL extracts had a higher total phenolic content than commercial products, but their antioxidant activity was lower. Sensory evaluation revealed that gummies containing seaweed extracts received lower scores for colour, taste, overall impression, and purchase intention than those without extracts.

Nowadays marine and coastal ecosystems are threatened by the invasion of harmful algal species. The solution to this situation should be aimed at the integral use of this biomass. The drying process has a decisive impact on the quality of the resulting raw material and the cost of any derived by-products. For this reason, the objective of this research is to evaluate the drying process of macroalgae: Sargassum fluitans, Ulva lactuca and Chaetomorpha cf. gracilis, using a solar dryer designed for this purpose. The drying process was evaluated at a temperature of 60°C. The results obtained reported that dehydration in the oven lasted less than 2 hours, while in the solar dryer values higher than those achieved in the oven were recorded. The first derivative analysis shows that the highest peak of moisture loss is around 80 % and is reached in the first 15 min in the electric stove. However, in solar drying it was recorded around 45 min. The results obtained in the drying process were adjusted to a polynomial model with a determination coefficient of 99,13 %. [ABSTRACT FROM AUTHOR]

Copyright of Indonesian Fisheries Processing Journal / Jurnal Pengolahan Hasil Perikanan Indonesia is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AbstractThis study examined the effectiveness of removing copper (Cu (II)) ions from leachate using three different live algae species (Chlorella vulgaris, Spirogyra ellipsospora, and Ulva lactuca), both individually and in combination. Various algal doses were tested to assess their impact on metal removal efficiency and algal growth. Five distinct masses (5, 10, 15, 20, and 25 g L−1) of each alga were grown in a batch experiment on leachate containing 3 mg L−1 of Cu (II) ions. It was found that the optimum algal dose is between 12.5 and 17.5 g L−1, and the optimum equilibrium duration was between 3 and 4.5 days for tested algal species. Under the optimum conditions of algal dose and contact time, the algae exhibited growth and Cu (II) ions removal efficiency in the order of Spirogyra ellipsospora > mixed algae > Chlorella vulgaris > Ulva lactuca. The study concludes that the selection of right algal species is crucial to optimize the growing environment for copper-contaminated leachate bioremediation. [ABSTRACT FROM AUTHOR]

The use of high-value fatty acids (FA), omega-3 (n-3), and omega-6 (n-6) from seaweed could relieve the pressure from natural wild fish sources and reduce overfishing worldwide. This research is designed to explore how the harvest season (winter, spring, and summer) and culture period influence the biomass production yield, lipid content, and FA composition in the green seaweed Ulva sp. The studied seaweed was grown in plastic sleeves with flowthrough seawater in Mikhmoret (East Mediterranean, Israel) from July 2019 to December 2020. The Ulva species was identified as Ulva lactuca Linnaeus by DNA barcoding using rbcL, ITS, and tufA markers. No detectable genetic variability in U. lactuca samples was found throughout the research period. A quantitative examination of the lipid and FA content in U. lactuca in different harvest seasons revealed that the maximum content of lipids was in the summer, and that of polyunsaturated fatty acids (PUFAs) was in the winter. The PUFA profile included eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid, n-3, and n-6, where the n-6/n-3 ratio was comparable with the desired range for a balanced nutritional diet. [ABSTRACT FROM AUTHOR]

Aims: This study aims to determine the antibacterial potential and identify the bioactive compounds of Hypoxylon monticulosum isolated from marine macroalgae Ulva lactuca. Methodology and results: Ulva lactuca was collected from the Desaru coast, Johor, Malaysia and three endophytes were isolated following surface sterilisation. One fungal isolate was further characterised by the morphology of white, yellowish colonies and fibrous with a waxy structure indicative of a member from the genus Hypoxylon. Molecular identification through internal transcribed spacer (ITS) sequence analysis matches the reference sequence with more than ≥98% homology to Hypoxylon monticulosum AS26-D8. Minimum inhibition concentration (MIC) of the fungal ethyl acetate (EA) extract was determined against five human pathogenic bacteria. Wide spectrum antibacterial activity was noted; with MIC against Escherichia coli was 1.25 ± 0 mg/mL, Bacillus subtilis and Enterobacter faecalis both at 5.00 ± 0 mg/mL, and finally, both Staphylococcus aureus and Klebsiella pneumoniae were 10.00 ± 0 mg/mL, respectively. Bioassay-guided fractionation was performed using solvents of increasing polarities, producing three fractions and analysis by liquid chromatography-mass spectrometry (LC/MS) identified 128 compounds. From these, nine compounds were identified as having biological activities. Dihydrocordoin, D-pantothenoyl-L-cysteine, caffeine and Tumonoic A acid were among the compounds identified as having antibacterial properties. Conclusion, significance and impact of study: Hypoxylon monticulosum from marine source has antibacterial potential owing to the compounds previously reported to display antibacterial and other biological properties. The compounds differ from those previously reported in H. monticulosum from terrestrial sources. [ABSTRACT FROM AUTHOR]

In our study on the effect of cadmium (Cd) toxicity (200 µM) on the growth of Sorghum bicolor (L.) Moench plants, cultivated with arbuscular mycorrhizal fungi (AMF) (Glomus intraradices) and/or under seaweed treatment (3% Ulva lactuca extract) (U. lactuca), we found that AMF increased the tolerance of sorghum to cadmium stress, either alone or in combination with the seaweed treatment. Morphological parameters were higher in these two culture conditions, with increased chlorophyll content. AMF reduced Cd accumulation in roots and inhibited its translocation to the aerial part, while seaweed treatment alone significantly increased Cd accumulation in leaves and roots without affecting plant growth compared to stressed witnesses. Treatment with AMF and/or U. lactuca attenuated oxidative stress, measured by activation of superoxide dismutase, and resulted in a significant decrease in malondialdehyde and superoxide ions (O2−) in treated plants. Furthermore, it induced significant alterations in carbon and nitrogen metabolic pathways, with a significant increase in the activity of enzymes such as glutamine synthetase, glutamate synthase (GOGAT), glutamate dehydrogenase, phosphoenolpyruvate carboxylase, aspartate aminotransferase and isocitrate dehydrogenase in the leaves of each treated plant. These results confirm that AMF, U. lactuca algae extract and their combination can improve the biochemical parameters of sorghum under Cd stress, through modification of the antioxidant response on one hand, and improved nitrogen absorption and assimilation efficiency on the other. [ABSTRACT FROM AUTHOR]

Utilization of macroalgae, which accumulated in the coastal area and considered as waste by municipals, for biofuel production is a good solution putting forward for both waste management and meeting the renewable energy requirement. This study aims to investigate the use of Ulva lactuca collected from the Marmara Sea coast as a raw material for solid biofuel production. Therefore, in this study, the combustion characteristics of Ulva lactuca and its biochar were investigated by the thermogravimetric method, and kinetic parameters were determined by using Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods. When the obtained thermograms are examined, it was observed that the combustion of raw seaweed occurs in three phases, while the combustion of biochars occurs in two phases. As a result of the calculations, the combustion activation energies of macroalga and its biochar were found to be approximately 261 kJ/mol and 146 kJ/mol, respectively, using the KAS method. It was found that the values calculated using the FWO method were similar to the KAS method. These data show that biochar requires less energy than raw algae during combustion. [ABSTRACT FROM AUTHOR]

Abstract Seaweeds, including the green Ulva lactuca, can potentially reduce competition between feed, food, and fuel. They can also contribute to the improved development of weaned piglets. However, their indigestible polysaccharides of the cell wall pose a challenge. This can be addressed through carbohydrase supplementation, such as the recombinant ulvan lyase. The objective of our study was to assess the muscle metabolism of weaned piglets fed with 7% U. lactuca and 0.01% ulvan lyase supplementation, using an integrated transcriptomics (RNA-seq) and proteomics (LC–MS) approach. Feeding piglets with seaweed and enzyme supplementation resulted in reduced macronutrient availability, leading to protein degradation through the proteasome (PSMD2), with resulting amino acids being utilized as an energy source (GOT2, IDH3B). Moreover, mineral element accumulation may have contributed to increased oxidative stress, evident from elevated levels of antioxidant proteins like catalase, as a response to maintaining tissue homeostasis. The upregulation of the gene AQP7, associated with the osmotic stress response, further supports these findings. Consequently, an increase in chaperone activity, including HSP90, was required to repair damaged proteins. Our results suggest that enzymatic supplementation may exacerbate the effects observed from feeding U. lactuca alone, potentially due to side effects of cell wall degradation during digestion.

Ulva Lactuca, commonly known as sea lettuce, is a green seaweed species that has attracted significant attention due to its remarkable potential as a prolific source of bioactive compounds. This comprehensive review explores the various extraction techniques harnessed to isolate these bioactive compounds from Ulva Lactuca while shedding light on the diverse health applications these compounds encompass. Within the review, considerable emphasis is placed on detailing the plethora of bioactive compounds inherent to Ulva Lactuca, spanning polysaccharides, phenolic compounds, fatty acids, pigments, minerals, and vitamins. Furthermore, a comprehensive analysis of the potential health benefits of these bioactive constituents is provided, encompassing their roles in antioxidant activity, anti-inflammatory properties, cardiovascular health, neuroprotection, and skin health enhancement. Addressing the broader scope of this review, significant attention is given to the challenges that currently permeate this field of research, including issues related to sustainability, standardization of extraction processes, formulation strategies, and avenues for further exploration. This examination culminates in the realization that Ulva Lactuca is a promising and versatile reservoir of bioactive ingredients, potentially revolutionising various industries such as food, pharmaceuticals, and cosmetics. Consequently, the future promises exciting prospects for the continued exploration and exploitation of Ulva Lactuca's wealth of bioactive compounds.

Seaweeds, including the green Ulva lactuca, can potentially reduce competition between feed, food, and fuel. They can also contribute to the improved development of weaned piglets. However, their indigestible polysaccharides of the cell wall pose a challenge. This can be addressed through carbohydrase supplementation, such as the recombinant ulvan lyase. The objective of our study was to assess the muscle metabolism of weaned piglets fed with 7% U. lactuca and 0.01% ulvan lyase supplementation, using an integrated transcriptomics (RNA-seq) and proteomics (LC–MS) approach. Feeding piglets with seaweed and enzyme supplementation resulted in reduced macronutrient availability, leading to protein degradation through the proteasome (PSMD2), with resulting amino acids being utilized as an energy source (GOT2, IDH3B). Moreover, mineral element accumulation may have contributed to increased oxidative stress, evident from elevated levels of antioxidant proteins like catalase, as a response to maintaining tissue homeostasis. The upregulation of the gene AQP7, associated with the osmotic stress response, further supports these findings. Consequently, an increase in chaperone activity, including HSP90, was required to repair damaged proteins. Our results suggest that enzymatic supplementation may exacerbate the effects observed from feeding U. lactuca alone, potentially due to side effects of cell wall degradation during digestion. [ABSTRACT FROM AUTHOR]

Excess inorganic nitrogen in offshore estuarine areas can adversely affect coastal water quality. To explore the bioremediation potential of Ulva lactuca in low-salinity and high-nutrient water, the dissolved inorganic nitrogen (DIN) removal under different low salinities (0, 0.5, 1.0, 1.5, 2.0% NaCl) and high nutrients was studied. Static culture experiments exhibited a maximum DIN removal efficiency of 73.74% with U. lactuca in the 1.0% salinity system. The differences in DIN removal efficiency at 1.0, 1.5 and 2.0% NaCl salinity were not significant (p > 0.05 and could reach above 65%. High-throughput sequencing, scanning electron microscopy (SEM) and excitation emission matrix (EEM) analysis demonstrated that the diversity of microorganisms decreased with increasing salinity with Proteobacteria and Bacteroidota the main phyla, revealing the synergistic effect of U. lactuca and microbes. Response surface curves showed that the conditions affecting DIN removal efficiency from high to low were salinity, density, and C/N ratio. By simulating the fluctuation of salinity and water level in the offshore estuarine environment, the efficient DIN removal was more than 60% and dissolved oxygen (DO) concentration was about 8 mg L−1 with U. lactuca at salinity above 1.0% NaCl. In conclusion, this study explored the DIN removal pattern of U. lactuca in different low-salinity and high-nutrient water environments, which is of great importance for the ecological restoration of estuarine and coastal environments. [ABSTRACT FROM AUTHOR]

Ulee Lheue Beach in Banda Aceh was developed for tourism. The macroalgae and seaweed species found in this area have been widespread but never exploited. Among these species is the green seaweed, Ulva lactuca, commonly known as sea lettuce. The physiological variations and genetic features of the seaweed can be attributed to the variations in the coastal environment. This study aims to describe the molecular identity of the genetic diversity of U. lactuca from the intertidal zone at Ulee Lheue Beach. The development of molecular biotechnology has enabled identification the gene expression through genomic DNA to PCR amplification. Genetic distance was determined using UPGMA. The results from 600-bp fragments were analyze the genetic diversity. A total of 15 (31%) expression identified as polymorphic (>0.500). Heterozygosity (He) and allelic differential (Na) diversity were found of 1.500-3.000. The highest PIC was observed in the rbcL1, with a correlation between subpopulations of 0.459. PCR amplification using the degenerate primer rbcL1 produced fragments ranging from 300 to 460 bp, whereas the expression of UL2 was detected at 448 and 500 bp using the rbcL2 primer. The phylogenetic identify are shown two (2) clusters. The populations of UL1, UL3, and UL4 were found a close relationship. Furthermore, the UL1 and UL2 populations were further divided into distinct clusters but related to the main branch of UL3. Based on this research, the concern of U. lactuca species for industrial and biotechnology destinations, we can describe a suitable method for obtaining he genetic distances between species. [ABSTRACT FROM AUTHOR]

Marine algal extracts exhibit a potent inhibitory effect against several enveloped and non-enveloped viruses. The infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has several adverse effects, including an increased mortality rate. The anti-COVID-19 agents are still limited; this issue requires exploring novel, effective anti-SARS-CoV-2 therapeutic approaches. This study investigated the antiviral activity of an aqueous extract of Ulva lactuca, which was collected from the Gulf of Suez, Egypt. The aqueous extract of Ulva lactuca was characterized by high-performance liquid chromatography (HPLC), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Energy Dispersive X-ray (EDX) analyses. According to the HPLC analysis, the extract comprises several sugars, mostly rhamnose (32.88%). The FTIR spectra showed numerous bands related to the functional groups. EDX analysis confirmed the presence of different elements, such as oxygen (O), carbon (C), sulfur (S), magnesium (Mg), potassium (K), calcium (Ca), and sodium (Na), with different concentrations. The aqueous extract of U. lactuca (0.0312 mg/mL) exhibited potent anti-SARS-CoV-2 activity via virucidal activity, inhibition of viral replication, and interference with viral adsorption (% inhibitions of 64%, 33.3%, and 31.1%, respectively). Consequently, ulvan could be a promising compound for preclinical study in the drug development process to combat SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Dental caries is an infectious oral disease caused by the presence of different bacteria in biofilms. Multidrug resistance (MDR) is a major challenge of dental caries treatment. Swabs were taken from 65 patients with dental caries in Makkah, Saudi Arabia. Swabs were cultivated on mitis salivarius agar and de Man, Rogosa, and Sharpe (MRS) agar. VITEK 2 was used for the identification of isolated bacteria. Antibiotic susceptibility testing of the isolated bacteria was performed using commercial antibiotic disks. Ulva lactuca was used as a reducing agent and cellulose source to create nanocellulose and Ag/cellulose nanocomposites. Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction spectroscopy (XRD) were used to characterize nanocellulose and Ag/cellulose nanocomposites. The results showed that most bacterial isolates were Streptococcus spp., followed by Staphylococcus spp. on mitis salivarius media. Lactobacillus spp. and Corynebacterium group f-1 were the bacterial isolates on de Man, Rogosa, and Sharpe (MRS) media. The antibiotic susceptibility test revealed resistance rates of 77%, 93%, 0, 83%, 79%, and 79% against penicillin G, Augmentin, metronidazole, ampicillin, ciprofloxacin, and cotrimoxazole, respectively. Ag/cellulose nanocomposites and Ag/cellulose nanocomposites with fluoride were the most effective antibacterial agents. The aim of this work was to assess the antibacterial activity of Ag/cellulose nanocomposites with and without fluoride against bacteria isolated from the oral cavities of patients with dental caries. This study demonstrated that Ag/cellulose nanocomposites have antibacterial properties against multidrug-resistant bacteria that cause dental caries. [ABSTRACT FROM AUTHOR]

In the present study, we have prepared seaweed-based nutritious edible cones through per cent optimization of composite flour level using Box-Behnken design for response surface methodology. The three independent variables of the statistical design were pearl millet, wheat and seaweed powder from Ulva lactuca and Gracilaria edulis, and overall acceptability (OAA) and retention time (RT) were considered responses. A secondorder quadratic polynomial equation was applied to the dataset of all responses to make predictions. U. lactucaincorporated cones showed that the overall desirability function fits with the quadratic model at 99.77% significance level at a combination of 27.75% for pearl millet, 7.38% of wheat and 0.986% for U. lactuca with a predicted OAA of 8.2 and RT of 23.93 min, whereas in G. edulis cone, at 99.34% level of significance, the point prediction was at 27.94%, 7.95% and 1.006% for pearl millet, wheat and G. edulis with a predicted OAA of 8.331 and RT of 24.6 min. [ABSTRACT FROM AUTHOR]

In the past, the occurrence of macro alga Ulva lactuca on the coastal areas of Jeju Island, Korea, has resulted in the expansion of devastating green tides, thus affecting coastal sustainability, aesthetic appearances, and tourism activities. Taking consideration of the above scenario, substantial economic costs are required for the environmental protection of the island, and it is highly recommended to employ Ulva lactuca in an alternative useful way. Hence, this paper proposes a new strategy to utilize Ulva lactuca as a tribopositive layer in a triboelectric nanogenerator (TENG). Based on the coastal bio-waste Ulva lactuca, the fabricated TENG device generates a maximum output voltage of 875 V, output current of 52 μA, and power density of 272.72 μW/cm2. Furthermore, the device presents excellent cyclic stability with no degradation in the output voltage even after 10000 consecutive cycles at a frequency of 2 Hz. The proposed TENG is further employed to charge the various commercially available capacitors, lightning LEDs, power stopwatches, and scavenge energy from body motions. It is anticipated that the proposed TENG device will pave a new way towards Ulva lactuca management for sustainable energy harvesting and clean coastlines.

Ulva polysaccharide (ULP) as main active ingredient of Ulva lactuca, has good pharmacological activity. This study further explored its anti-tumor mechanisms in hepatocellular carcinoma (HCC) with wet experiments and bioinformatic analyses. Results indicate that the differential proteins after ULP treatment are mainly enriched in immunomodulatory and complement pathways, among which the immune molecule CD5L and the key proteins of the membrane attack complex (MAC) are significantly upregulated, and the expression of MAC proteins are positively correlated with the expression of CD5L. Moreover, results from TIMER2.0 indicated that CD5L expression had positive correlation with CD8 + T cell infiltration in HCC, and single cell RNA-Seq analysis showed CD5L positive macrophage cells have higher expression of CFP, C1QA, C1QB, and C1QC, which are key molecular of complement cascades. Take together, the results suggest that ULP may exerts its anti-tumor activity by induces the expression of CD5L in HCC.

Bacterial pathogens cause pain and death, add significantly to the expense of healthcare globally, and pose a serious concern in many aspects of daily life. Additionally, they raise significant issues in other industries, including pharmaceuticals, clothing, and food packaging. Due to their unique properties, a great deal of attention has been given to biogenic metal nanoparticles, nanocomposites, and their applications against pathogenic bacteria. This study is focused on biogenic silver and copper nanoparticles and their composites (UL/Ag2 O-NPS, Ul/CuO-NPs, and Ul/Ag/Cu-NCMs) produced by the marine green alga Ulva lactuca. The characterization of biogenic nanoparticles UL/Ag2 O-NPS and Ul/CuO-NPs and their composites Ul/Ag/Cu-NCMs has been accomplished by FT-IR, SEM, TEM, EDS, XRD, and the zeta potential. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) experiments were conducted to prove antibacterial activity against both Gram-positive and Gram-negative bacteria and anti-biofilm. The FTIR spectroscopy results indicate the exiting band at 1633 cm−1, which represents N–H stretching in nanocomposites, with a small shift in both copper and silver nanoparticles, which is responsible for the bio-reduction of nanoparticles. The TEM image reveals that the Ul/Ag/Cu-NCMs were hexagonal, and the size distribution ranged from 10 to 35 nm. Meanwhile, Ul/CuO-NPs are rod-shaped, whereas UL/Ag2 O-NPS are spherical. The EDX analysis shows that Cu metal was present in a high weight percentage over Ag in the case of bio-Ag/Cu-NCMs. The X-ray diffraction denotes that Ul/Ag/Cu-NCMs, UL/CuO-NPs, and UL/Ag2 O-NPS were crystalline. The results predicted by the zeta potential demonstrate that Ul/Ag/Cu-NCMs were more stable than Ul/CuO-NPs. The antibacterial activity of UL/Ag2 O-NPS, Ul/Ag/Cu-NCMs, and UL/CuO-NPs was studied against eleven Gram-negative and Gram-positive multidrug-resistant bacterial species. The maximum inhibition zones were obtained with UL/Ag2 O-NPS, followed by Ul/Ag/Cu-NCMs and Ul/CuO-NPs in all the tested bacteria. The maximum anti-biofilm percentage formed by E. coli KY856933 was obtained with UL/Ag2 O-NPS. These findings suggest that the synthesized nanoparticles might be a great alternative for use as an antibacterial agent against different multidrug-resistant bacterial strains. [ABSTRACT FROM AUTHOR]

Seaweed extracts are extensively used as fertilizers across the globe. However, their mechanism of action and effects are less understood and need to be studied in detail. The present study investigated the effect of Ulva lactuca seaweed extract as a liquid fertilizer (SLF) on the growth characteristics of green gram. The seeds of green gram were soaked in varied concentrations of aqueous seaweed extract like 2, 4, 6, 8 and 10 %. Additionally, the SLF was applied on germinated seedlings as foliar spray treatment in 2 days interval. The maximum growth parameters were observed in foliar spray treatment at 8 % concentration and in seed soaking treatment at 2 % concentration. The seaweed extract was effective in influencing the growth characteristics of green gram. [ABSTRACT FROM AUTHOR]

ULVA selenium nanoparticles (USeNPs) were synthesized and characterized, then examined for their wound healing capacity through in vitro assay showing promising healing (82.27%) with USeNPs concentration (500µg/mL). We also determined the antifungal potential via agar well diffusion technique, minimum inhibitory concentration (MIC), which was evaluated by a micro-dilution assay. The synergistic effect of the USeNPs individually or in combination with standard antifungal antibiotic (ketoconazole;100μg/mL) was studied against Cryptococcus neoformans RCMB 0049001 and Candida lipolytica RCMB 005007(1). Geotrichum candidum RCMB 041001 was also checked by agar well diffusion assay, followed by transmission electron microscopy to assess different changes in the most sensitive fungal yeast cells. The results indicated that USeNPs have a promising antifungal effect against C. neoformans RCMB 0049001 and C. lipolytica RCMB 005007(1) by achieving remarkable inhibition zones. In comparison, no effect was detected on G. candidum RCMB 041001. The MIC was found to be 78.1μg and 312.5μg for C. neoformans RCMB 0049001 and C. lipolytica RCMB 005007(1), respectively. The biosynthetic USeNPs have a strong antifungal potential and can elevate and strengthen the action of ketoconazole antibiotic towards different fungal pathogens, and this was obvious In the experiment of synergism carried out in the present study based on combining ketoconazole;100μg/mL with USeNPs, which resulted in a detached C. neoformas RCMB 0049001 cells with a severe dramatic change. [ABSTRACT FROM AUTHOR]

Abstract Various antibiotics are available, including gentamicin, chloramphenicol, ampicillin, amoxicillin, and streptomycin, but they have some restrictions. Many microorganisms are resistant to these medications. A new antimicrobial source must be found or developed to solve this issue. Inhere, extract from seaweeds Ulva lactuca was investigated for its antibacterial activity using a well diffusion assay against Klebsiella pneumoniae, and a promising inhibition zone diameter was recorded to be 14.04 mm. The biochemical structure of the antibacterial compound was determined via GC-MS and FTIR analysis. Also, a micro-dilution assay was used to calculate the minimum concentration that makes inhibition (MIC) to be 1.25 mg/ml from U. extract reliable to prevent the visibility of any bacterial growth, this was followed by examining the antibacterial effect of U. Lactuca methanolic extract alone and the synergetic effect of U. Lactuca methanolic extract in combination with two different antibiotics (gentamicin and chloramphenicol). This was assayed by the agar well diffusion method to achieve promising and strong inhibiting power against K. pneumoniae. It was deduced that the maximum synergism could be achieved by adding 2.5 mg/ml of Ulva methanolic extract to gentamicin (4 µg/ml), and the results were illustrated obviously via transmission electron microscope in which severe morphological deteriorations were experienced by the treated cells. From this study, we can conclude that U. lactucae extract has the power to aid antibiotics in reducing the growth of pathogenic K. pneumoniae.

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.

Within the framework of the valorization of the marine algal biomass of the Algerian coast, our study consists of a phytochemical screening and an evaluation of the anti-inflammatory and antioxidant activity of the methanolic extract of the green alga Ulva lactuca from the Algerian west coast (Ain Temouchent). Anti-inflammatory activity was determined by the bovine serum albumin (BSA) denaturation assay, while antioxidant activity was determined by DPPH radical scavenging activity. The results of phytochemical screening of the algae studied showed a diversity of secondary metabolites produced, namely flavonoids and tannins, and the absence of terpenoids, free quinones, and reducing compounds. In the present study, the maximum effect of inhibition of BSA denaturation was observed at a concentration of 150 µg/ml, with 51, 65%, and 53.74% for our extract and diclofenac, respectively. With an IC50 of 107.94 µg/ml for the methanolic extract and 23.03 µg/ml for Diclofenac. For antioxidant activity results, the percentage of DPPH inhibition is 58.79% at the 800 µg/ml concentration. Our green alga shows positive antioxidant activity with an IC50 of 592.776 μg/ml. According to the results, our seaweed extract has anti-inflammatory and antioxidant properties. Our findings are still preliminary, and further research is needed to fully understand the mode of action of the bioactive compounds and the optimal therapeutic dosage. This could lead to the production of pharmaceutical products with significant therapeutic value [ABSTRACT FROM AUTHOR]

The increasing clinical and microbiological resistance of Candida species towards several commonly prescribed antifungal agents has stimulated the search for new active antifungal compounds from natural resources. The most important virulence factors of pathogenic Candida species are biofilm formation and hyphal development, making treatment very challenging due to the spread of resistant Candida isolates. This study was designed to explore the potential of different types of Ulva lactuca extracts on the growth of Candida spp., and evaluate the morphological alterations and time-kill as well. Methanol was the best solvent for extracting bioactive components from the examined algae Ulva lactuca (Chlorophyta) exhibiting the highest antifungal effect, followed by ethanol and chloroform. The minimum inhibition concentration (MIC) of U. lactuca methanol extract (ULME) was 62.5mg/ml, and the minimum fungicidal concentration (MFC) was 125mg/ml against all the tested oral Candida spp. Different concentrations of ULME (1xMIC, 2xMIC and 4xMIC) influenced the micromorphology of the tested oral Candida spp. and had an impact on biofilm formation. In the time-kill curves, ULME showed a concentration-dependent fungicidal effect. The cytotoxicity results showed that ULME has no significant toxic effects against normal human lung fibroblast cells (MRC-5 cell line). Moreover, the major phytochemical compounds were fatty acids, identified and quantified by using Gas Chromatography-Mass Spectrometry (GC/MS). In conclusion, ULME may be an alternative to conventional antifungal drugs for the treatment of oral candidiasis. [ABSTRACT FROM AUTHOR]

Introduction: Studies have shown that the macroalga Ulva lactuca is the largest CO2 receptor. In Cuba, the possibility of installing a plant for its intensive cultivation is being evaluated, which contributes to mitigate CO2 and allows obtaining algal biomass in a sustainable way. For design calculations, equipment selection and operating conditions, it is necessary to know the maximum biomass yieldand its photosynthetic equation. Objective: To estimate quantitatively the CO2 fixation mechanism of the macroalga Ulva lactuca, using different alternatives of the photosynthesis equation based on the calculation of stoichiometric coefficients. Materials and Methods: To calculate the yield and the amounts of substrate and nutrients that the biomass is able to assimilate, mass balances are carried out to optimize the production of algal biomass, applying the method of stoichiometric coefficients in the photosynthesis reaction. Results and Discussion: The maximum cell yield of Ulva lactuca is 63.5 %. Of the photosynthesis equations proposed, alternative four has values closer to photosynthetic reality, since there is a great correspondence between the stoichiometry of microalgae growth and product formation, together with the availability of nitrogen and phosphorus sources. Both results allow us to deduce the production of microalgal biomass to implement an economically and environmentally profitable technology. Conclusions: The maximum biomass yield and the photosynthetic equation allow for design calculations, equipment selection and operating conditions to scale up the technological process. [ABSTRACT FROM AUTHOR]