Preparation and functional properties of beverages made from sea algae

Padina Minor Extract Confers Resistance against Candida Albicans Infection: Evaluation in a Zebrafish Model

Padina minor is a seaweed rich in polysaccharides often used in food, feed, fertilizers, and antibacterial drugs. This study is the first to evaluate the effect of feeding zebrafish with Padina minor extract on preventing and treating C. albicans infections. This study evaluated the growth, survival, and disease resistance effects of P. minor extract on zebrafish. The fish were divided into four groups: three groups treated with 1%, 5%, or 10% P. minor extract and one untreated group (c, control). Subsequently, we analyzed how the extract affected the immune function of zebrafish infected with C. albicans. Based on the lethal concentration (LC50) calculated in the first stage, 1% was used as the effective therapeutic concentration. The results showed that the growth rate of the 1% feed group was the best, and no significant difference in survival rates between the four groups was observed. Feeding with 1% P. minor extract downregulated the expression of key inflammatory genes like tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-10, effectively preventing and treating C. albicans infections in zebrafish. This study is a preliminary evaluation of the therapeutic efficacy of P. minor extracts against C. albicans.

Rapid and cost-efficient microplate assay for the accurate quantification of total phenolics in seaweeds

Brown seaweeds (Phaeophyceae) are a rich source of polyphenols (up to 20% dry weight) with a structure based on phloroglucinol (1,3,5-trihydroxybenzene). To-date the determination of total phenolics content (TPC) involves a redox reaction with the Folin-Ciocalteu (FC) reagent. However, side reactions with other reducing substances preclude accurate, direct measurement of TPC. This research reports a novel microplate assay involving a coupling reaction between phloroglucinol with Fast Blue BB (FBBB) diazonium salt, at basic pH, to form a stable tri-azo complex with maximum absorbance at 450 nm. Linear regression correlation values (R²) were ≥0.99 with phloroglucinol as standard. Direct quantification of TPCs (phloroglucinol equivalents, PGEs) in crude aqueous and ethanolic extracts from A. nodosum demonstrated that the new FBBB assay is not subject to side-redox interference and provides a more accurate estimate of TPC (1.2-3.9-fold lower than with the FC assay) in a relatively rapid (30 min), cost-effective (0.24€/test) microplate format.

Characterization and in vitro assessment of seaweed bioactives with potential to reduce methane production

This study collates compositional analysis of seaweeds data with information generated from in vitro gas production assays in the presence and absence of seaweeds. The aim was to assess and rank 27 native northern European seaweeds as potential feed ingredients for use to reduce methane emissions from ruminants. It provides information for use in future in vivo dietary trials concerning feed manipulation strategies to reduce CH4 emissions efficiently from domestic ruminants based on dietary seaweed supplementation. The seaweeds H. siliquosa and A. nodosum belonging to phylum Phaeophyta displayed the highest concentration of phlorotannins and antioxidant activity among the macroalgae giving anti-methanogenic effect in vitro, while this explanation was not valid for the observed reduction in methane when supplementing with C. filum and L. digitata in this study. D. carnosa and C. tenuicorne belonging to phylum Rhodophyta had the highest protein content among the macroalgae that reduced methane production in vitro. There were no obvious explanation from the compositional analysis conducted in this study to the reduced methane production in vitro when supplementing with U. lactuca belonging to phylum Chlorophyta. The strongest and most complete methane inhibition in vitro was observed when supplementing with Asparagopsis taxiformis that was used as a positive control in this study.

Current Status and Future Trends in Removal, Control, and Mitigation of Algae Food Safety Risks for Human Consumption

With the rapid development of the economy and productivity, an increasing number of citizens are not only concerned about the nutritional value of algae as a potential new food resource but are also, in particular, paying more attention to the safety of its consumption. Many studies and reports pointed out that analyzing and solving seaweed food safety issues requires holistic and systematic consideration. The three main factors that have been found to affect the food safety of algal are physical, chemical, and microbiological hazards. At the same time, although food safety awareness among food producers and consumers has increased, foodborne diseases caused by algal food safety incidents occur frequently. It threatens the health and lives of consumers and may cause irreversible harm if treatment is not done promptly. A series of studies have also proved the idea that microbial contamination of algae is the main cause of this problem. Therefore, the rapid and efficient detection of toxic and pathogenic microbial contamination in algal products is an urgent issue that needs to be addressed. At the same time, two other factors, such as physical and chemical hazards, cannot be ignored. Nowadays, the detection techniques are mainly focused on three major hazards in traditional methods. However, especially for food microorganisms, the use of traditional microbiological control techniques is time-consuming and has limitations in terms of accuracy. In recent years, these two evaluations of microbial foodborne pathogens monitoring in the farm-to-table chain have shown more importance, especially during the COVID-19 pandemic. Meanwhile, there are also many new developments in the monitoring of heavy metals, algal toxins, and other pollutants. In the future, algal food safety risk assessment will not only focus on convenient, rapid, low-cost and high-accuracy detection but also be connected with some novel technologies, such as the Internet of Things (artificial intelligence, machine learning), biosensor, and molecular biology, to reach the purpose of simultaneous detection.

Antifungal, Antiviral, and HPLC Analysis of Phenolic and Flavonoid Compounds of Amphiroa anceps Extract

The increasing use of chemical control agents and pesticides to prevent plant disease has resulted in several human and environmental health problems. Seaweeds, e.g., Amphiroa anceps extracts, have significant antimicrobial activities against different human pathogens. However, their anti-phytopathogenic activities are still being investigated. In the present investigation, three fungal isolates were isolated from root rot and grey mold symptomatic strawberry plants and were molecularly identified by ITS primers to Fusarium culmorum, Rhizoctonia solani, and Botrytis cinerea with accession numbers MN398396, MN398398, and MN398400, respectively. In addition, the organic extract of the red alga Amphiroa anceps was assessed for its antifungal activity against the three identified fungal isolates and tobacco mosaic virus (TMV) infection. At 100 µg/mL, the A. anceps extract had the best biological activity against R. solani, B. cinerea, and TMV infection, with inhibition rates of 66.67%, 40.61%, and 81.5%, respectively. Contrarily, the A. anceps extract exhibited lower activity against F. culmorum, causing inhibition in the fungal mycelia by only 4.4% at the same concentration. The extract’s HPLC analysis revealed the presence of numerous phenolic compounds, including ellagic acid and gallic acid, which had the highest concentrations of 19.05 and 18.36 µg/mL, respectively. In this line, the phytochemical analysis also showed the presence of flavonoids, with the highest concentration recorded for catechin at 12.45 µg/mL. The obtained results revealed for the first time the effect of the A. anceps extract against the plant fungal and viral pathogens, making the seaweed extract a promising source for natural antimicrobial agents.

The Effect of Sargassum siliquastrum Supplementation on Growth Performance, Cecal Fermentation, Intestine Histomorphology, and Immune Response of Japanese Quails

This study aimed to investigate the dietary effects of Sargassum siliquastrum on the growth performance, nutrient digestibility, cecal fermentation, microbial populations, antioxidant status, immune response, and intestine histomorphology of Japanese quails. A total of 450 Japanese quails, aged 7 days, weighing 27.35 ± 0.23 g, were randomly distributed to three dietary groups in a 42-day feeding experiment. Five replicates were prepared per group, with each replicate consisting of 30 chicks in a cage. The three dietary groups consisted of a basal diet (0% supplementation, which was the control) and diets supplemented with 1% and 2% of S. siliquastrum. The results showed that the S. siliquastrum-supplemented groups and the control group had a similar final body weight (FBW), average body gain (ADG), and average feed intake (ADFI). However, the S. siliquastrum-supplemented groups had a better feed conversion ratio (FCR), as well as a lower mortality rate, compared to the control group. S. siliquastrum supplementation improved the nutrient digestibility of dry matter (DM), organic matter (OM), crude proteins (CP), and crude fibers (CF) (p < 0.05). The S. siliquastrum-supplemented groups exhibited the heaviest empty intestine and cecum weights, as well as the longest intestinal and cecal lengths. Furthermore, the total volatile fatty acids (TVFA) and the propionic acid concentrations increased significantly in quails fed S. siliquastrum-supplemented diets (p < 0.05), although the concentration of NH3-N decreased (p < 0.05). The dietary inclusion of S. siliquastrum had a beneficial effect on cecal microbial populations, where the Lactobacillus sp. counts increased, and the E. coli and Clostridium perfringens counts decreased. The histopathological examination of the duodenum confirmed that S. siliquastrum dietary supplementation enhanced the height and width of the villi. Quails fed S. siliquastrum-supplemented diet exhibited the highest total antioxidant capacity, superoxide dismutase, glutathione peroxidase, and glutathione reductase activities, but the thiobarbituric acid reactive substance was decreased (p < 0.05). Serum IgA, IgG, and IgM concentrations increased considerably (p < 0.05) in S. siliquastrum-supplemented groups. In conclusion, S. siliquastrum supplementation in the diet of Japanese quail can provide beneficial effects on performance, cecal fermentation, beneficial bacteria populations, and the immune response, and could be considered as an alternative feed additive in poultry production.

An Overview on Effects of Processing on the Nutritional Content and Bioactive Compounds in Seaweeds

The effect of the different processing technologies and the extraction techniques on the bioactive compounds and nutritional value of seaweeds is reviewed in this study. This work presents and discusses the main seaweeds treatments such as drying, heating, and culinary treatments, and how they affect their nutritional value, the bioactive compounds, and antioxidant capacity. Some examples of traditional and green extraction technologies for extracting seaweeds bioactive components are also presented. The last trends and research on the development of seaweed-based food products is also covered in this review. The use of environmentally friendly extraction procedures, as well as the development of new healthy seaweed-based foods, is expected to grow in the near future.

In Vitro Enzyme Inhibitory Properties, Secondary Metabolite Profiles and Multivariate Analysis of Five Seaweeds

Seaweeds have been exploited as both food products and therapeutics to manage human ailments for centuries. This study investigated the metabolite profile of five seaweeds (Halimeda spp., Spyridia hypnoides (Bory de Saint-Vincent) Papenfuss, Valoniopsis pachynema (G. Martens) Børgesen, Gracilaria fergusonii J. Agardh and Amphiroa anceps (Lamarck) Decaisne using ultra-high-performance liquid chromatography coupled with electrospray ionization mass spectrometry (UHPLC-ESI-MS/MS). Furthermore, these seaweeds were assessed for antioxidant and inhibitory effects against α-amylase, α-glucosidase, acetyl-cholinesterase (AChE), butyryl-cholinesterase (BChE) and tyrosinase. Valoniopsis pachynema and A. anceps yielded the highest flavonoid (4.30 ± 0.29 mg RE/g) and phenolic content (7.83 ± 0.08 mg RE/g), respectively. Additionally, A. anceps exhibited significant antioxidant properties with all assays and significantly depressed BChE (IC₅₀ = 6.68 ± 0.83 mg/mL) and α-amylase activities (IC₅₀ = 5.34 ± 0.14 mg/mL). Interestingly, the five seaweeds revealed potent inhibitory effects against tyrosinase activity. In conclusion, A. anceps might be considered as a key source of phytoantioxidants and a potential candidate to develop nutritional supplements. Besides, the five tested seaweeds warrant further study and may be exploited as promising natural sources for managing hyperpigmentation.

Evaluation of antioxidant activities of various solvent extract from Sargassum serratifolium and its major antioxidant components

Sargassum serratifolium has been known to contain a high level of meroterpenoids as antioxidant components. We investigated antioxidant activities and active components in various solvent extracts from S. serratifolium. Ethyl acetate, ethanol, and methanol extracts showed relatively strong DPPH, ABTs, and superoxide radical scavenging activities. Hexane and ethyl acetate extract showed the strongest hydroxyl radical and reactive oxygen species (ROS), respectively, scavenging activities. Sargahydroquinoic acid (SHQA), sargachromanol (SCM) and sargaquinoic acid (SQA) were main antioxidant components in S. serratifolium. Ethanol extract showed the highest levels of SHQA, SCM, and SQA which comprised to be 227 ± 6.31 mg/g. SHQA and SCM exhibited stronger antioxidant capacities than SQA based on lower IC50 values in ROS, DPPH, ABTs, and superoxide radical scavenging assays. The result showed that ethanol is the most efficient extracting solvent for the active components from S. serratifolium and the plant has the potential as a natural antioxidant.

Cardiotoxicity and myocardial infarction-associated DNA damage induced by thiamethoxam in vitro and in vivo: Protective role of Trigonella foenum-graecum seed-derived polysaccharide

The risk of pesticides on the human health and environment has drawn increasing attention. Today, new tools are developed to reduce pesticide adverse effects. This study aimed to evaluate the toxicity induced by, thiamethoxam (TMX), and the cytoprotective effect of a novel polysaccharide, named fenugreek seed water polysaccharide (FWEP) in vitro using H9c2 cardiomyoblastes and in vivo using Wistar rat model. Animals were assigned into four groups per eight rats each: group 1 served as a control group, group 2 received TMX, group 3, and group 4 received both FWEP and TMX tested at two doses (100 and 200 mg/kg, respectively). Regarding the in vitro study, our results demonstrated that TMX induced a decrease in H9c2 cell viability up to 70% with the highest concentration. In vivo, TMX injection induced marked heart damage noted by a significant increase in plasma lactate dehydrogenase, creatine phosphokinase, troponin-T, aspartate amino transferase activities, cholesterol, and triglyceride levels. Concomitant alterations in cardiac antioxidant defense system revealed depletion in the levels of glutathione and non-protein thiol and an increase in the activity of superoxide dismutase, catalase, and glutathione peroxidase. Similarly, a significant increase in heart lipid, malondialdehyde, advanced oxidation protein product and in protein carbonyls levels was also noted. In addition, heart tissues histo-architecture displayed major presence of apoptosis and necrosis as confirmed by DNA degradation. However, supplementation with FWEP alleviated heart oxidative damage and genotoxicity. In this manner, ABTS radical-scavenging activity, linoleic acid oxidation tests and heart genomic and DNA nicking assay had proved FWEP strong antioxidant potential. In conclusion, FWEP provided significant protection against TMX-induced heart injury, and could be a useful and efficient agent against cardiotoxicity and atherosclerosis.

Anti-Oxidant and Fucoxanthin Contents of Brown Alga Ishimozuku (Sphaerotrichia divaricata) from the West Coast of Aomori, Japan

Fucoxanthin is a specific carotenoid in brown seaweeds with remarkable biological properties. Ishimozuku (Sphaerotrichia divaricata), an edible brown alga from northern Japan, has morphology that is almost identical to that of Okinawa-mozuku (Cladosiphon okamuranus) harvested off Okinawa, Japan. However, because of Ishimozuku's lower availability compared to Okinawa-mozuku, the contents of its nutrient compounds remain unclear. The present study analyzed fucoxanthin and anti-oxidant compound contents of Ishimozuku harvested off the northern coast of Japan from 2014 to 2016. First, 80% ethanol extract solutions were prepared from Ishimozuku harvested from several west coast areas of Aomori, Japan. Then, polyphenol content was analyzed using the Folin⁻Ciocalteu method. Then anti-oxidative effects were analyzed by their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and hydrogen peroxide scavenging activity. Furthermore, fucoxanthin contents were measured using high performance liquid chromatography (HPLC) analysis. Fucoxanthin contents of Ishimozuku were 105.6⁻1148.5 μg/g dry weight. Total polyphenol contents of Ishimozuku were of 0.296⁻0.958 mg/g dry weight: higher than Okinawa-mozuku (0.082 ± 0.011 mg/g dry weight). The anti-oxidation effects of Ishimozuku accompanied the polyphenol content. These results suggest that Ishimozuku contains various anti-oxidant components and has high potential to provide the promotion of human health.

Total fractionation and characterization of the water-soluble polysaccharides isolated from Enteromorpha intestinalis

Water-soluble crude polysaccharides (WE) were extracted from the Enteromorpha intestinalis with hot water and further fractionated on a DEAE-52 Cellulose chromatography column and Sepharose CL-6B gel-permeation chromatography to afford one neutral fraction (WE-11) and five acidic fractions (WE-21, WE-31, WE-32, WE-41 and WE-42). Monosaccharide analysis showed that WE-32, WE-41 and WE-42 were all composed of Rha and GlcA, WE-21 and WE-31 contained Man and Rha, and WE-11 was composed of GlcA and Xyl. The molecular weight of WE-11, WE-21, WE-31 WE-32, WE-41 and WE-42 were 2.23 × 10⁵, 1.42 × 10⁵, 1.42 × 10⁵, 2.62 × 10⁴, 2.23 × 10⁵ and 8.09 × 10^4, respectively. Then, antioxidant activities in vitro were investigated on the basis of DPPH radical assay, reducing power assay, hydroxyl radical assay and superoxide radical assay. Of all polysaccharides fractions, WE-32 and WE-41 had relative higher content of sulfate and GlcA. In addition, WE-32 and WE-41 showed relative stronger antioxidant activity and inhibitory activity in vitro. The antioxidant activities of polysaccharides were not a function of a single factor but a combination of several factors, such as monosaccharide composition, molecular weights, protein content, uronic acid and sulfate content.

In vitro biological properties and health benefits of a novel sulfated polysaccharide isolated from Cymodocea nodosa

BACKGROUND

During the last few decades, there has been a growing interest in the search for novel bioactive compounds from marine origins.

METHODS

The present study is the first to determine the molecular characterization which it was deposited in the genebank database, to investigate and evaluate the biological properties of sulfated polysaccharide from Cymodocea nodosa (CNSP) seagrass.

RESULTS

The results revealed that CNSP had high activity in total antioxidant assay (59.03 mg ascorbic acid equivalents/g extract), reducing power (OD = 0.3), DPPH radical scavenging (IC₅₀ = 1.22 mg/ml) and ABTS radical scavenging (IC₅₀ = 1.14 mg/ml). It was also noted to exhibit antimicrobial activity against a wide range of microorganisms, with important inhibition zones. The results revealed that CNSP was able to inhibit the proliferation of Hela cell lines with a dose-dependent manner.

CONCLUSION

Overall, the results presented in this study demonstrate that CNSP has several attractive antioxidant, antimicrobial and antiproliferative properties with potential benefits towards health.

Brown Algae Padina sanctae-crucis Børgesen: A Potential Nutraceutical

Padina sanctae-crucis Børgesen is distributed worldwide in tropical and subtropical seas; belongs to the Dictyotaceae family, and has proven to be an exceptional source of biologically active compounds. Four compounds were isolated and identified, namely: dolastane diterpene new for the genus Padina; phaeophytin and hidroxy-phaeophytin new for the family Dictyotaceae, and; mannitol first described in this species. Saturated fatty acids as compared to the percentages of unsaturated fatty acids were shown to be present in greater abundance. Palmitic and linolenic acid were the main saturated and unsaturated acids, respectively. Cytotoxic and antioxidant activities were evaluated using human erythrocytes. In vivo evaluations of acute toxicity and genotoxicity were performed in mice. Methanolic extract of P.sanctae-crucis presented antioxidant activity and did not induce cytotoxicity, genotoxicity or acute toxicity. Since Padina sanctae-crucis is already used as food, has essential fatty acids for the nutrition of mammals, does not present toxicity and has antioxidant activity, it can be considered as a potential nutraceutical.

Antioxidant Activity of Hizikia fusiformis on Reactive Oxygen Species Scavenging and Lipid Peroxidation Inhibition

Water and organic extracts (diethyl ether, chloroform, ethyl acetate, acetone, ethanol and methanol) obtained from Hizikia fusiformis were screened on reactive oxygen species (ROS) scavenging assays (1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide anion, hydrogen peroxide and hydroxyl radical) and lipid peroxidation (inhibition of linoleic acid oxidation) inhibitory assays. Water, methanol and ethanol extracts showed significant ROS radical scavenging activities. Water extracts showed high scavenging activities on hydrogen peroxide (around 76%) and DPPH radicals (around 75%) while it presented a moderate scavenging activity on hydroxyl radicals (around 54%). Comparatively higher ROS scavenging activities were recorded in hydroxyl radical and DPPH scavenging assays. DPPH radical scavenging activities were well correlated with the polyphenolic content. ROS scavenging and lipid peroxidation inhibition activities indicated that H. fusiformis might be a valuable natural antioxidative source containing both water and fatsoluble antioxidative components.

Seaweeds as Preventive Agents for Cardiovascular Diseases: From Nutrients to Functional Foods

Being naturally enriched in key nutrients and in various health-promoting compounds, seaweeds represent promising candidates for the design of functional foods. Soluble dietary fibers, peptides, phlorotannins, lipids and minerals are macroalgae's major compounds that can hold potential in high-value food products derived from macroalgae, including those directed to the cardiovascular-health promotion. This manuscript revises available reported data focusing the role of diet supplementation of macroalgae, or extracts enriched in bioactive compounds from macroalgae origin, in targeting modifiable markers of cardiovascular diseases (CVDs), like dyslipidemia, oxidative stress, vascular inflammation, hypertension, hypercoagulability and activation of the sympathetic and renin-angiotensin systems, among others. At last, the review also describes several products that have been formulated with the use of whole macroalgae or extracts, along with their claimed cardiovascular-associated benefits.

Enzyme-assisted extraction of cactus bioactive molecules under high hydrostatic pressure

BACKGROUND

To improve the extraction and recovery of bioactive materials from cactus, the present study investigated the effect of polysaccharide-degrading enzymes [Rapidase-Viscozyme mixture, 1/3 (v/v)] treatment under high hydrostatic pressure (HHP).

RESULTS

The dry weight of the extract increased with the use of increasing pressure regardless of enzyme treatment. However, the polyphenol content showed a tendency to decrease with the increase in pressure in the cactus extract with or without enzyme treatment. The enzyme-assisted extraction resulted in an increase of dry weight and polyphenol content in the cactus extract. The total sugar and reducing sugar contents of the cactus extract increased with increasing pressure in enzyme-assisted extraction. The uronic acid content of the cactus extract showed a pattern similar to that of the reducing sugars. The enzyme-assisted extraction also increased the contents of taxifolin, quercetin and isorhametin. The cactus extract obtained through enzyme-assisted extraction showed intense scavenging activity of both DPPH and ABTS radicals. The crude polysaccharides isolated from the extract (51.2% at 1000 µg mL⁻¹ for HHP extraction at 300 MPa) had higher anti-complementary activity than the others except for lipopolysaccharide (60.00% at 1000 µg mL⁻¹). HHP extraction and enzyme-assisted extraction using HHP showed an increase of anti-complementary activity compared with the heat and enzyme controls, respectively.

CONCLUSION

Overall, the use of HHP in enzyme-assisted extraction resulted in more efficient extraction than the use of enzyme treatment alone.

In vitro antimicrobial and antioxidant activities of seaweeds from hare island, Tuticorin coast of India

OBJECTIVE

To assess the antimicrobial and antioxidant activities from methanolic extracts of brown and red seaweeds.

METHODS

Padina tetrastromatica, Stocheopremum marginatum and Phorphyra sp. were evaluated by in vitro standard methods. In antimicrobial assay, P. tetrastromatica extract showed highest zone inhibition against E. coli and S. typhi. The S. marginatum extract exhibited the maximum zone inhibition against S. typhi, minimum against K. pneumonia. Phorphyra sp. extract showed higher sensitivity against T. mirabilis. The antioxidant activities of seaweeds were determined at different concentration of 100, 300 and 500 μg/mL.

RESULTS

In 1,1-diphenyl-2-picrylhydrazyl (DPPH) and total phenolic content assays, the S. marginatum extract was found the highest reducing power and the lowest showed by Phorphyra sp. and S. marginatum extracts. In the Linoleic acid peroxidation assay, the P. tetrastromatica extract showed the highest reducing power and minimum showed in S. marginatum extract. The Fourier-transform infrared spectra of the three seaweed extracts exhibited a strong broad, medium, weak and broadly-stretched peak at around 3,400 cm-1.

CONCLUSION

Our study indicates that the seaweeds are potential source for antimicrobial and antioxidant agents and further study will fulfill for the purification and structural characterization of the compounds.

In vitro antioxidant and antitumor activities of different sulfated polysaccharides isolated from three algae

Three sulfated polysaccharides(Ulva fasciata (UFP), Gloiopeltis furcata (GFP), Sargassum henslouianum (SHP))were isolated from three algae including green alga Ulva fasciata, red alga Gloiopeltis furcata and brown alga Sargassum henslouianum by ultrasonic extraction and radial flow chromatography. Their in vitro antioxidant and antitumor activities were investigated and compared. Among these three polysaccharides, UFP, with relatively lower sulfate content, exhibited excellent antioxidant activities in superoxide radical assay, ABTS assay and DPPH assay; however, it demonstrated the minimal inhibitory effects on growth of MKN45 gastric cancer cells and DLD intestinal cancer cells. SHP with the lowest sulfate content gained relatively lower radical scavenging rates but showed significantly higher antitumor activities. These results indicated that the in vitro antitumor and antioxidant activities of the three polysaccharides may be related to combined effects of sulfate content and uronic acid content.

Antibacterial substances from marine algae isolated from Jeddah coast of Red sea, Saudi Arabia

Marine algae are known to produce a wide variety of bioactive secondary metabolites and several compounds have been derived from them for prospective development of novel drugs by the pharmaceutical industries. However algae of the Red sea have not been adequately explored for their potential as a source of bioactive substances. In this context Ulva reticulata, Caulerpa occidentalis, Cladophora socialis, Dictyota ciliolata, and Gracilaria dendroides isolated from Red sea coastal waters of Jeddah, Saudi Arabia, were evaluated for their potential for bioactivity. Extracts of the algae selected for the study were prepared using ethanol, chloroform, petroleum ether and water, and assayed for antibacterial activity against Escherichia coli ATCC 25322, Pseudomonas aeruginosa ATCC 27853, Stapylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212. It was found that chloroform was most effective followed by ethanol, petroleum ether and water for the preparation of algal extract with significant antibacterial activities, respectively. Results also indicated that the extracts of red alga G. dendroides were more efficient against the tested bacterial strains followed by green alga U. reticulata, and brown algae D. ciliolata. Chemical analyses showed that G. dendroides recorded the highest percentages of the total fats and total proteins, followed by U. reticulata, and D. ciliolate. Among the bioflavonoids determined Rutin, Quercetin and Kaempherol were present in high percentages in G. dendroides, U. reticulata, and D. ciliolate. Estimation of saturated and unsaturated fatty acids revealed that palmitic acid was present in highest percentage in all the algal species analyzed. Amino acid analyses indicated the presence of free amino acids in moderate contents in all the species of algae. The results indicated scope for utilizing these algae as a source of antibacterial substances.

Anti-genotoxic effect of the Sargassum dentifolium extracts: prevention of chromosomal aberrations, micronuclei, and DNA fragmentation

The alga Sargassum dentifolium (Turner) C. Agardh, belongs to Sargassaceae, is a brown seaweed in red sea shores in Egypt. This work aimed to extract different water-soluble polysaccharide extracts (E1, E2, and E3) from S. dentifolium and to investigate their protective effect against cyclophosphamide (CP)-induced genotoxicity. Mice bone marrow cells (BMCs) were collected and analyzed for the chromosomal aberration, micronucleated BMCs (MN-BMCs), the mitotic index, DNA fragmentation by comet assay, and histone deacetylases (HDACs), and radical scavenging capacity of extracts was evaluated by the oxygen radical absorbance capacity assay. The results indicated that E2 and E3 significantly inhibited CP-induced multiple chromosomal aberrations, where E1 and E3 significantly suppressed the number of CP-induced formation of tetraploidy. The extracts prohibited the cytotoxic effect of CP and recovered the mitotic activity, whereas E1 possessed the highest recovery and mitosis. In absence of MN, CP induced formation of bi- and poly-nucleated BMCs. E1 prohibited CP-induced formation of bi-nucleated BMCs, while E2 and E3 prohibited CP-induced formation of poly-nucleated BMCs. CP-induced MN-BMCs were accompanied with mono-, bi- and poly-nucleated cells. E1 and E3 remarkably suppressed mono-nucleated MN-BMCs, while E2 inhibited bi-nucleated MN-BMCs. All the extracts significantly inhibited the CP-induced formation of poly-nucleated MN-BMCs. CP-induced DNA fragmentation was inhibited by all extracts, where E1 was the strongest inhibitor as concluded from the comet tail moment. All the extracts were strong OH scavengers, while only E3 was ROO scavenger. The results revealed a drastic decline in HDACs activity by E1 and E3. In conclusion, S. dentifolium polysaccharide extracts E1 and E3 possessed a potential anti-genotoxic and a promising anti-mutagenic activity.

Marine algae sulfated polysaccharides for tissue engineering and drug delivery approaches

Biomedical field is constantly requesting for new biomaterials, with innovative properties. Natural polymers appear as materials of election for this goal due to their biocompatibility and biodegradability. In particular, materials found in marine environment are of great interest since the chemical and biological diversity found in this environment is almost uncountable and continuously growing with the research in deeper waters. Moreover, there is also a slower risk of these materials to pose illnesses to humans.   In particular, sulfated polysaccharides can be found in marine environment, in different algae species. These polysaccharides don't have equivalent in the terrestrial plants and resembles the chemical and biological properties of mammalian glycosaminoglycans. In this perspective, are receiving growing interest for application on health-related fields. On this review, we will focus on the biomedical applications of marine algae sulfated polymers, in particular on the development of innovative systems for tissue engineering and drug delivery approaches.

Algae as promising organisms for environment and health

Algae, like other plants, produce a variety of remarkable compounds collectively referred to as secondary metabolites. They are synthesized by these organisms at the end of the growth phase and/or due to metabolic alterations induced by environmental stress conditions. Carotenoids, phenolic compounds, phycobiliprotein pigments, polysaccharides and unsaturated fatty acids are same of the algal natural products, which were reported to have variable biological activities, including antioxidant activity, anticancer activity, antimicroabial activity against bacteria-virus-algae-fungi, organic fertilizer and bioremediation potentials.