Salina Extract Research Articles

Exploring the uncharted seas: Metabolite profiling unleashes the anticancer properties of Oscillatoria salina

Marine cyanobacteria offer a rich source of varied natural products with both chemical and biological diversity. Oscillatoria salina (O. salina) is a filamentous non-heterocystous marine cyanobacterium from Oscillatoriaceae family. In this investigation, we have unveiled bioactive extracts from O. salina using two distinct solvent systems, revealing significant anticancer properties. Our assessment of the organic and aqueous extracts (MCE and AE) of O. salina demonstrated pronounced antiproliferative and antimetastatic effects. Notably, this study is the first to elucidate the anticancer and anti-metastatic potential of O. salina extracts in both 2D and 3D cell culture models. Both MCE and AE induced apoptosis, hindered cell proliferation, invasion, and migration in A549 non-small cell lung cancer cells, accompanied by alterations in cell morphology and cytoskeleton collapse. Moreover, MCE and AE induced spheroid disintegration in A549 cells. Transcriptomics analysis highlighted the significant involvement of Rap1 and p53 signaling pathways in mediating the observed antitumor effects. Mass spectroscopy characterization of these extracts identified 11 compounds, some known for their anticancer potential. HPLC analysis of AE revealed six peaks with UV absorption spectra resembling phycocyanin, a cyanobacterial pigment with well-known anticancer activity. Collectively, these findings underscore the anticancer potential of MCE and AE, containing bioactive metabolites with anticancer and antimetastatic properties.

Enhancing the bioactivity of Dunaliella salina extracts through ultra-high pressure supercritical fluid extraction (UHP-SFE)

Dunaliella salina is a green microalga known for its high carotene content, especially in β-carotene isomers, which are very interesting compounds due to their biological activity. The neuroprotective effect of β-carotene has been related to the potential prevention of multifactorial neurological pathologies. The use of green extraction processes for the extraction of carotenoids present in D. salina has generated a great advance in the production of carotenoid-enriched extracts. In this work, supercritical fluid extraction at ultra-high pressure (UHP-SFE) at semi-pilot scale has been evaluated for the first time for the extraction of β-carotene isomers from D. salina. The effect of the pressure was determined by an experimental design, and results showed that both the carotenoid extraction and the neuroprotective activity of the obtained extracts were maximum at 84.9 MPa. At this ultra-high pressure, the extraction yield was improved 1.35 times, the total terpene and carotene content increased 2.02 and 1.61 times, respectively, and the neuroprotective activity was 2.44 and 1.60 (for acetylcholinesterase and butyrylcholinesterase inhibition capacity, respectively) higher in comparison to the CP-SFE extract. Therefore, UHP-SFE is presented as a more selective extraction process with a higher potential to generate enriched extracts with increased bioactivity than SFE procedures under moderate pressure conditions. Moreover, it has been demonstrated that the use of the semi-pilot UHP-SFE process had a greener potential for the recovery of bioactive carotenoid-enriched extracts than the analytical scale process. Industrial relevanceThe industrial scaling-up of extraction processes is a current need. In this sense, in this work, the semi-pilot SFE process has been shown as a more automatic and safer process than the analytical scale. Additionally, the use of UHP in the SFE semi-pilot scale has allowed reducing the extraction time to half of the initial time obtaining higher extraction yields. The UHP-SFE extract provides enriched carotene products with increased neuroprotective activity with greater industrial performance. Therefore, this work becomes the starting point for achieving a high throughput β-carotene extract process at industrial scale.

Efficacy and safety of artificial tears containing Artemia salina extract with dinucleotides for dry eye

ABSTRACT Clinical relevance This clinical trial was conducted as part of the marketing procedures for a medical device comprising artificial tears containing Artemia salina extract with dinucleotides. These molecules previously demonstrated secretagogue properties by enhancing the production of aqueous, mucinous, and lipidic components of the tears. Background After confirming the efficacy of artificial tears containing Artemia salina extract in an animal model, this study proceeded to evaluate their efficacy and safety on dry eye participants. Methods A randomised controlled clinical trial was performed on 36 dry eye participants (41.6 ± 20.6 years). Half of the participants were treated with saline solution as a placebo for four weeks, while the other half were treated with artificial tears containing Artemia salina, randomly assigned. After a wash-out period of two weeks, the treatments were crossed for another four weeks. Participants were assessed at baseline and after one week, two weeks, and four weeks. Efficacy variables were: eye dryness frequency (primary), eye comfort, visual satisfaction, tear secretion, tear break-up time, corneal staining, conjunctival staining, and conjunctival hyperaemia. Safety variables were: high- and low-contrast visual acuity, intraocular pressure, and eye fundus images analysis. Results Compared with the baseline, the saline solution showed no significant changes in any of the studied variables after four weeks of treatment (p ≥ 0.05). However, the topical instillation of the artificial tears with Artemia salina for four weeks significantly improved eye dryness frequency (p = 0.014) and corneal staining (p = 0.010). No systemic or ocular adverse events were reported during the clinical trial. Conclusion The topical instillation of artificial tears containing Artemia salina in mild to moderate dry eye participants for four weeks slightly improved their symptoms related to eye dryness frequency and reduced corneal damage, with no undesirable side effects observed.

Chemical constituents of ostracod Heterocypris salina extract, anticancer and antimicrobial activity: in silico supported in vitro study

Background The majority of bioactive compounds derived from the sea have been extracted from aquatic invertebrates. While Ostracods are a diverse class of crustaceans that inhabit marine, brackish, and freshwaters, there are no available studies testing Ostracoda in the medical field. Objective The aim of this work was to produce H. salina on a large scale to evaluate its crude extract for anticancer and antimicrobial activities. Materials and methods Ostracod, Heterocypris salina was collected from its habitat in the eastern side of Lake Manzalla, Egypt, and the species was cultured in Soaba System of the National Institute of Oceanography and Fisheries (NIOF), Al-Khairia City, Egypt). Crude extract of Heterocypris salina was prepared and the extract was tested as an anticancer against different human cancer cell lines. Also, the extract was investigated as antimicrobial against different Gram-positive and Gram-negative bacteria. In addition, chemical composition of the extract by GC-MS analysis and molecular docking were also studies. Results and conclusion Ostracod Heterocypris salina was cultured, at day 50 of the culturing, about 500 L of the culturing pond was harvested using plankton to collect the biomass of H. salina. A methanol extract of H. salina was prepared and showed a moderate to good anticancer effect against liver (HepG2), lung (A549), colon (HCT), and breast (MCF7) cancer cell lines with IC50 values in the range of 12.8–23.2 µg/ml), being safe for the healthy cells of the same organs. Also, the H. salina extract showed activity against three tested Gram-negative (Escherichia coli, Klebsiella pneumonia, and Salmonella typhi) and two Gram-positive (Sarcina lutea and Bacillus cereus) bacteria. GC-MS analysis of H. salina extract revealed the presence of 11 compounds including ethyl iso-allocholate (23.1%), 9(Z)-octadecenamide, (Z)-(20.6%), oleic acid (12.3%), palmitic acid (11.65%), and α-amyrin (10.73%). Moreover, a molecular docking study was performed in order to determine the possible binding interactions of the test compounds with the essential amino acids in the binding site of thymidylate kinase (TMK).

Dunaliella salina Alga Protects against Myocardial Ischemia/Reperfusion Injury by Attenuating TLR4 Signaling.

Myocardial ischemia/reperfusion (I/R) injury is marked by rapid increase in inflammation and not only results in myocardial apoptosis but also compromises the myocardial function. Dunaliella salina (D. salina), a halophilic unicellular microalga, has been used as a provitamin A carotenoid supplement and color additive. Several studies have reported that D. salina extract could attenuate lipopolysaccharides-induced inflammatory effects and regulate the virus-induced inflammatory response in macrophages. However, the effects of D. salina on myocardial I/R injury remain unknown. Therefore, we aimed to investigate the cardioprotection of D. salina extract in rats subjected to myocardial I/R injury that was induced by occlusion of the left anterior descending coronary artery for 1 h followed by 3 h of reperfusion. Compared with the vehicle group, the myocardial infarct size significantly decreased in rats that were pre-treated with D. salina. D. salina significantly attenuated the expressions of TLR4, COX-2 and the activity of STAT1, JAK2, IκB, NF-κB. Furthermore, D. salina significantly inhibited the activation of caspase-3 and the levels of Beclin-1, p62, LC3-I/II. This study is the first to report that the cardioprotective effects of D. salina may mediate anti-inflammatory and anti-apoptotic activities and decrease autophagy through the TLR4-mediated signaling pathway to antagonize myocardial I/R injury.

Phytochemical Screening and Toxicity Test of Various Extracts from Microalgae <I>Dunaliella salina</I>

Highlight Research Extract N-hexane of salina contains alkaloids, steroids, triterpenoids, and phenols Extract Ethyl Acetate of salina contains alkaloids, steroids, triterpenoids, phenols, flavonoid, and saponins Extract Methanol of salina contains alkaloids, steroids, triterpenoids, phenols, flavonoid, and saponins 24- hours LC50 value of the n-hexane extract salina was 276 ppm, the ethyl acetate extract was 673 ppm and the methanol extract was 811 ppm. All of the three extracts were included in toxic category Abstract Microalgae are single celled microorganisms as the primary producers in the water food cycle. Microalgae bioactive compounds was estimated to be 10 times more diverse than compounds produced by land plants. Microalgae use nutrients more efficiently to grow, metabolize, and produce chemical compounds. Dunaliella salina is a type of chlorophyte microalgae with a lot of potential to be used in various fields. This study aimed to determine the phytochemical compound content and the value of lethal toxicity (24-hour LC50) in microalgae D. salina extract with different solvents. The multistage maceration method uses n-hexane, ethyl acetate, and methanol to extract samples. Phytochemical screening uses reagents according to the content of secondary metabolites. The Brine Shrimp Lethality Test method is used to test toxicity. The extracts were tested by using 10 Artemia salina against five concentrations, namely 0, 1, 10, 100, and 1000 ppm. Toxicity data were processed through probit analysis to get the 24-hour LC50 value. The results showed that alkaloids, steroids, triterpenoids, and phenols were found in the methanol, ethyl acetate, and n-hexane extracts. Saponin were found in the methanolic extracts. Flavonoid were found in the methanol and ethyl acetate extracts. The 24-hour LC50 value of the n-hexane extract was 276 ppm, the methanol extract was 811 ppm, and ethyl acetate extract was 673 ppm. The three extracts were included in toxic category. Extracts of microalgae D. salina have plenty secondary metabolite, that can be used in various fields and holds the potential as an anticancer.

In-Vivo Test Addition of Dunaliella salina Extract to Commercial Feed on Clinical Symptoms and Anatomical Pathology of Cantang Grouper after Viral Nervous Necrosis (VNN) infection

Viral Nervous Necrosis (VNN) is a pathogen that is often found infecting cantang grouper and causing mass mortality of up to 100% in a short time. VNN is caused by a Nodavirus infection that infects the nervous and visual systems of fish. One of the prevention efforts against VNN infection in cantang grouper is to add Dunaliella salina extract which contains -carotene, nephtalene, tetradecane and phenol which acts as antiviral, anti-microbial and anti-inflammatory. The purpose of this study was to examine the potency of D. salina extract against clinical symptoms and anatomical pathology of cantang grouper after VNN infection. D. salina extract with doses of 250, 300, 350 and 400mg/kg of feed was added to commercial pelleted feed of the Stella B2 brand with a protein content of 42%. Feed was given to cantang grouper measuring 7-9 cm for 10 days of maintenance. Furthermore, the fish were challenged using VNN as much as 0.2 ml/head through the injection method. Observations of clinical symptoms and anatomical pathology were observed for 96 hours after infection. Symptoms of clinical pathology of fish infected with VNN appear to be circling, swimming horizontally, inflation of the swim bladder, discoloration of the pectoral fins to reddish, swollen lymph organs, yellowing of the liver and darkening of the body color. The compounds found in the extract of D. salina can be used to increase the immune response and reduce the number of deaths of cantang grouper infected with VNN. The addition of D. salina extract which was higher than other doses could increase the immune system so that its survival (SR) was higher as the dose increased.

A Dunaliella salina Extract Counteracts Skin Aging under Intense Solar Irradiation Thanks to Its Antiglycation and Anti-Inflammatory Properties.

Glycation, and the resulting buildup of advanced glycation end products (AGEs), is recognized as a key driver of cumulative skin damage and skin aging. Dunaliella salina is a halophile microalga adapted to intense solar radiation through the production of carotenoids. We present a natural supercritical CO2 extract of Dunaliella salina rich in the colorless carotenoids phytoene and phytofluene. The extract exhibited antiglycation and anti-inflammatory activities in ex vivo testing, showing strongly reduced formation of N-ε-carboxy-methyl-lysine with exposure to methylglyoxal, reduced AGE receptor levels, and significantly reduced interleukins 6 and 8. In a placebo-controlled clinical study under intense solar exposure, the extract significantly reduced the skin’s glycation scores and its sensitivity to histamine; key skin aging parameters were also significantly improved vs. placebo, including wrinkle counts and spots. These results demonstrate the value of this Dunaliella salina extract, rich in colorless carotenoids, as an antiglycative, anti-inflammatory, and antiaging active ingredient, including in high-irradiation contexts.

Study of the potential neuroprotective effect of Dunaliella salina extract in SH-SY5Y cell model

Alzheimer’s disease (AD) is the most common form of dementia caused by a progressive loss of neurons from different regions of the brain. This multifactorial pathophysiology has been widely characterized by neuroinflammation, extensive oxidative damage, synaptic loss, and neuronal cell death. In this sense, the design of multi-target strategies to prevent or delay its progression is a challenging goal. In the present work, different in vitro assays including antioxidant, anti-inflammatory, and anti-cholinergic activities of a carotenoid-enriched extract from Dunaliella salina microalgae obtained by supercritical fluid extraction are studied. Moreover, its potential neuroprotective effect in the human neuron-like SH-SY5Y cell model against remarkable hallmarks of AD was also evaluated. In parallel, a comprehensive metabolomics study based on the use of charged-surface hybrid chromatography (CSH) and hydrophilic interaction liquid chromatography (HILIC) coupled to high-resolution tandem mass spectrometry (Q-TOF MS/MS) was applied to evaluate the effects of the extract on the metabolism of the treated cells. The use of advanced bioinformatics and statistical tools allowed the identification of more than 314 metabolites in SH-SY5Y cells, of which a great number of phosphatidylcholines, triacylglycerols, and fatty acids were significantly increased, while several phosphatidylglycerols were decreased, compared to controls. These lipidomic changes in cells along with the possible role exerted by carotenoids and other minor compounds on the cell membrane might explain the observed neuroprotective effect of the D. salina extract. However, future experiments using in vivo models to corroborate this hypothesis must be carried out.Graphical abstract

Physicochemical and rheological characterisation of microalgae-enriched ketchups and their sensory acceptability

Ketchup is one of the most popular tomato sauces in the restaurant and catering sector. Ketchup provides accents of colour and flavouring, as well as a smell and texture that is familiar and comforting. When compared to traditional products, alternative recipes make use of new ingredients like microalgae and sweeteners, well-known because of their functional and sensory properties. In this study, ketchups, with and without sugar addition, along with microalgae biomasses Arthrospira platensis (Spirulina) and Chlorella vulgaris, and Dunaliella salina extract at different concentrations, were prepared and evaluated. Colour differences regarding to the control samples were used to select microalgae concentrations. Physicochemical, rheological, and sensory properties of selected samples were characterised. Adding microalgae resulted in darker samples with intensified green, blue, and yellow hues. The use of microalgae in the preparation of ketchup had an impact on the features of the prepared products, increasing the apparent viscosity and consistency, and showing a more structured system compared to control samples. Furthermore, the microalgae incorporation in ketchup recipes affected taste intensity and sweetness, influencing ketchup's acceptance.

Sugar and no sugar added fruit microalgae-enriched jams: a study about their physicochemical, rheological, and textural properties

Jams are preparations of fruits whose main preserving agent is sugar. Due to this, health concerns of consumers have resulted in a sugar reduction, and its replacement using alternative sweeteners and introducing new ingredients enhancing nutritional properties. In this study, four types of fruits jams (plum, strawberry, apple, and peach), with or without sugar, were prepared using two microalgae biomass, Arthrospira platensis (Spirulina) and Chlorella vulgaris, and Dunaliella salina extract as ingredients at different mix levels of concentrations, 0.10%–0.10%–0.05% respectively, for plum; 0.04%–0.00%–0.01 respectively, for strawberry; 0.06%–0.04%–0.00% respectively, for apple and 0.00%–0.01%–0.04% respectively, for peach. Physicochemical, rheological, and textural parameters were evaluated. Substitution of sugar/fructose syrup in the jam’s preparation caused changes in pH values, solid soluble content, and rheological and textural properties compared to sugar jams. Using sugar or sweeteners as isomalt, stevia and sucralose and microalgae biomass or extract showed significant changes in colour coordinates, however, these differences were not perceptible by the human eye. Jams containing microalgae biomass-extract showed higher G', G'', G*, and η* values than their corresponding control samples. All the jams presented weak-gel characteristics, distinguishing fruit jams. However, the results of weak-gel model analysis suggest that the influence of the different ingredients in the food system depends not only on their concentration but also on the interactions in the gel structure. Strawberry and apple jams showed no significant differences between microalgae biomass-extract samples and control samples, for both sugar and no sugar added jams being the best-obtained samples.

497 A Dunaliella salina extract counteracts skin aging under intense solar irradiation thanks to its anti-glycation and anti-inflammatory properties

497 A Dunaliella salina extract counteracts skin aging under intense solar irradiation thanks to its anti-glycation and anti-inflammatory properties

Effectiveness of Dunaliella salina Extracts against Bacillus subtilis and Bacterial Plant Pathogens.

Several bacteria pathogens are responsible for plant diseases causing significant economic losses. The antibacterial activity of Dunaliella salina microalgae extracts were investigated in vitro and in vivo. First, biomass composition was chemically characterized and subjected to extraction using polar/non-polar solvents. The highest extraction yield was obtained using chloroform:methanol (1:1 v/v) equal to 170 mg g−1 followed by ethanol (88 mg g−1) and hexane (61 mg g−1). In vitro examination of hexane extracts of Dunaliella salina demonstrated antibacterial activity against all tested bacteria. The hexane extract showed the highest amount of β-carotene with respect to the others, so it was selected for subsequent analyses. In vivo studies were also carried out using hexane extracts of D. salina against Pseudomonas syringae pv. tomato and Pectobacterium carotovorum subsp. carotovorum on young tomato plants and fruits of tomato and zucchini, respectively. The treated young tomato plants exhibited a reduction of 65.7% incidence and 77.0% severity of bacterial speck spot disease. Similarly, a reduction of soft rot symptoms was observed in treated tomato and zucchini fruits with a disease incidence of 5.3% and 12.6% with respect to 90.6% and 100%, respectively, for the positive control.

The effect of Dunaliella salina extract on NFkB expression in Cantang Grouper (Epinephelus fuscoguttatus x E. lanceolatus) exposed by Viral Nervous Necrosis

VNN is one of the viruses that can cause death in cantang grouper hatchery in Southeast Asia including Indonesia. The purpose of this research was to find out the expression of NFkB in cantang grouper brain which was exposed by VNN and treated by D. salina extract. Fifty hybrid groupers with 7-9 cm length were stocked in 5 containers with a density of 10 fish/container. Five treatments applied with different D. salina extracts are 0, 250, 300, 350 and 400 mg/kg feed. Feed treatment was given twice a day for 10 days before being challenged with VNN. The expression of NFkB was detected with immunohistochemistry tests and analyzed by immunoreaction software. The result showed that the highest NFkB expression is in treatment 0 mg/kg feed with a percentage of 66%, while the lowest expression is shown in 400 mg/kg feed with a percentage of 31,2%. Different dosages of D. salina have a significant effect on NFκB expression so that it can be concluded that D. salina has the potential as a VNN antiviral candidate in the grouper.

Dunaliella salina extract alleviates the toxic impact of Dioxin induced endocrine disruption in Nile tilapia

Pollution of lakes and seas in Egypt become a severe problem as it produces a lot of wastes and toxic chemicals. The water pollution induces a lot of endocrine disruptions in aquatic organisms. Several endocrine organs are influencing by pollution such as testes, ovaries, pituitary, hypothalamus, thyroid, and adrenal organs. Propositions of upsetting endocrine chemicals (EDCs) can meddle with fish larval advancement affecting the delicate balance of the biological ecosystem. Endocrine disruption effects on reproductive cycles may affect reproductive behaviour and the development of secondary sexual characteristics. So the main objective of this research is to use marine algae, Dunaliella salina, extract in fish immunity enhancement against pollutants. Nile tilapia fish were exposed to Dioxin (as the main pollutant in the Egyptian environment) after feeding on algae extracts for one month. The results revealed that Dunaliella salina was able to protect the fish against pollution as it enhances the immune capability of Nile tilapia fish due to increase the levels of the antioxidant enzymes and decrease the protein oxidation. Additionally, Dunaliella salina extract was able to decrease the alteration in the expression of genes encoding endocrine hormones such as LH and FSH in the pituitary of Nile tilapia exposed to Dioxin in comparison to control fish. Moreover, the Dunaliella salina extract decreased significantly the DNA damage in brain tissues of Nile tilapia exposed to Dioxin compared with control fish. The results conclude that Dunaliella salina could be used as ameliorative compounds against toxicity of Dioxin.

Antioxidant and anti-cancer activity of Dunaliella salina extract and oral drug delivery potential via nano-based formulations of gum Arabic coated magnetite nanoparticles

In the present study, a delivery system containing magnetic nanoparticles grafted with gum arabic (GA) for oral administration of Dunaliella salina extract (DE) was introduced. The physicochemical analysis of GA-coated MNPs via FT-IR, XRD, DLS, and TEM, showed the successful encapsulation, well-crystalized magnetite spherical uniform shape with >200 nm hydrodynamic size. Nanoparticles showed 54.36 emu/cm3 values with −1.12 mV ζ-potential and 6.8% content of GA. Encapsulation efficiency, release profile, antioxidant and anticancer potential were evaluated by UV–Vis spectroscopy, FRAP and MTT assay, respectively. Logarithmic and stationary growth phase DE were loaded onto GA-coated MNPs with loading efficiency and encapsulation capacity of 79.80 and 186.10, respectively. In vitro release study of DE in PBS with pH 4.5 and 7.2 showed relevant release percentage in neutral pH during first 8 h with final relative release values of 72.41 and 43.51% in logarithmic and stationary phase during 48 h, respectively. The antioxidant and cytotoxic activity of DE and DE loaded GA-MNPs on both MCF-7 and HeLa cells indicate that both phases showed strong antioxidant and anticancer effect in time and dose-dependent manner. These results suggest that D. salina extracts loaded GA-MNPs have high potency which are capable to operate as a successful formulation for oral drug delivery of antioxidants.

Minimum Inhibitory Concentration of Marine Microalgae Dunaliella salina on Fish Pathogenic Bacteria Edwardsiella tarda

Dunaliella salina is a type of marine microalgae. The objective of this research were investigated the effect of D. salina to inhibit the growth of E. tarda . The method used in this study was examined antibacterial activity of D. salina using disc diffusion and co culture test. The secondary metabolite compound in D. salina was tested using phytochemical screening and FTIR methods. The results obtained D. salina extracted using n-hexane showed the best activity for inhibiting the growth of E. tarda . Minimum concentration of 100 mg.L -1 crude extract can inhibit E. tarda with a total of bacterial colonies 137x10 11 CFU.mL -1 . The phytochemical test results showed that D. salina extract using n-hexane contained flavonoids, saponins, alkaloids, terpenoids and phenols. The FTIR analysis showed phenol and carotene compounds are one of the secondary metabolites that can be used as antibacterial. It can be concluded that the extract has strong antibacterial activity against E. tarda and potentially as antibacterial in aquaculture.

Antibacterial Potential of Chlorella vulgaris and Dunaliella salina Extracts Against Streptococcus mutans

Background and Objectives: Chlorella vulgaris and Dunaliella salina has been utilized as a part of nourishment and medicine to enhance the human way of life. This work was directed to assess the impacts of chloroform, methanol, and acetone (in ratio of 2/1/1 respectively) extract from C. vulgaris and D. salina on in-vitro biofilms formed by Streptococcus mutans along with their antibacterial activity. Methods: The standardized combinatorial extract was primarily examined for their antimicrobial properties using disc diffusion, well diffusion, minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) methods. The crystal violet assay was used for assessing anti-biofilm activity of S. mutans. Moreover, toxicity properties of these extracts were evaluated on Brine shrimp Artemia urmiana. Results: The best observed clear zones were 13.5 ± 0.92 mm for C. vulgaris and 18.5 ± 0.97 for D. salina in disc diffusion assay as well as 19 ± 0.87 mm for C. vulgaris and 25.4 ± 0.97 mm for D. salina in well diffusion assay. In addition, significant antibiofilm activity was recorded in the concentration of 4 mg/ml for C. vulgaris and 2 mg/ml for D. salina. Findings indicated appropriate antimicrobial activity for D. salina and C. vulgaris extract. Conclusions: In addition, the biofilms of S. mutans were more effectively prohibited by D. salina extract than C. vulgaris extract. Moreover, D. salina extract showed less mortality in comparison with C. vulgaris extract in brine shrimp mortality test. The anti-adherent and antibacterial potential of both microalgae on in vitro biofilms formed by S. mutans were verified, which provides the importance of studies regarding these microalgae extracts for controlling dental plaque formation and consequent dental cavities formation.

POTENTIAL OF DUNALIELLA SALINA MICROALGAE TO AMELIORATE HIGH-FAT DIET‑INDUCED OBESITY IN ANIMALS’ RODENT

Objective: This study was carried out to investigate the potential of Dunaliella salina microalgae to ameliorate obesity induced by high-fat diet (HFD) in male Wistar rats.Methods: Fifty rats weighing 150–160 g were fed HFD for 12 weeks. The rats were randomly divided into five groups of ten rats each. Obese rats were orally administered D. salina ethanolic extract (150 mg/Kg body weight), and orlistat as standard drug (12 mg/Kg body weight), for 6 weeks.Results: Treatment of obese rats with both D. salina and orlistat had a significant effect in reducing body and liver weights as well as visceral fat, inhibiting pancreatic lipase activity, decreased lipid profile, and increased fecal fat and ameliorating liver function enzymes activity, insulin, blood glucose, and leptin levels. Besides, food intake was insignificantly increased as a result of D. salina and orlistat treatments compared with normal control rats.Conclusion: It could be concluded that D. salina rich in β-carotene significantly reduced body weight gain and ameliorated several metabolic pathways implicated in obesity and its related complication. Hence, further intensive study must be carried out to formulate D. Salina extracts to apply as a promising natural anti-obesity nutraceutical drug.

Halophilic microalgaeDunaliella salinaextracts improve seed germination and seedling growth ofTriticum aestivumL. under salt stress

Salinity is among the major limiting factors of crop productivity worldwide. Salt stress affects the plant growth at all developmental stages. The present study investigates the potential of halotolerant microalgae Dunaliella salina extracts to suppress the inhibition of seeds germination and seedlings growth caused by salt stress on wheat (Triticum aestivum). Germination percentage and height of coleoptiles and root system were measured as a response of D. salina extracts treatment. Biomass hydrolyzate of D. salina cultured in different concentrations of NaCl (1, 2 and 4 M of NaCl) improved germination and seedling growth of wheat under salt stress. The effect of molecules accumulated in D. salina which are proline, carotenoids and exopolysaccharides on germination and seedling growth was investigated. Our results showed that exopolysaccharides extracted from the microalgae had the major stimulating effect on germination and seedling growth in wheat. Exopolysaccharides extracts from D. salina improved the germination percentage of wheat seeds under salt stress of 3 and 6 g L-1 NaCl by 96 and 83%, respectively, compared to control, while the height of root system was stimulated with 133 and 444% and the coleoptiles height was increased by 105 and 750% in response to 3 and 6 g L-1 NaCl, respectively, compared to control stressed untreated. Our study demonstrates that extracts of halotolerant microalgae especially exopolysaccharides could help plants to tolerate salt stress.