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Sterols profile of Chlorophyta, Phaeophyta and Rhodophyta from the Portuguese west coast. Results are presented as percentage of each sterol for the species corresponding to each seaweed group (294).
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Oceans comprise an immense diversity of living organisms, still underexplored if compared with terrestrial ones. Seaweeds are part of this diversity, constituting one of the most important groups of organisms, in both number and variety of species. Considering the constant search for new bioactive compounds, seaweeds have attracted scientists’ atte...
Citations
... They are composed of many phloroglucinol (1,3,5-trihydroxybenzene) (Figure 1) molecules that are linked together in various ways ( Figure 2) [64]. Phlorotannins can be split into six distinct groups based on the type of structural connections between phloroglucinol units and the quantity of hydroxyl groups present: phlorethols and fuhalols (phlorotannins with an ether linkage), fucols (which present a phenyl linkage), fucophlorethols (with an ether and phenyl linkage), eckols (with a dibenzodioxin linkage), and carmalols [65]. In the event of cellular damage, these substances are produced via the acetate-malonate pathway [66]. ...
... They are composed of many phloroglucinol (1,3,5-tr droxybenzene) (Figure 1) molecules that are linked together in various ways (Figur [64]. Phlorotannins can be split into six distinct groups based on the type of struct connections between phloroglucinol units and the quantity of hydroxyl groups pres phlorethols and fuhalols (phlorotannins with an ether linkage), fucols (which prese phenyl linkage), fucophlorethols (with an ether and phenyl linkage), eckols (with a dib zodioxin linkage), and carmalols [65]. In the event of cellular damage, these substa are produced via the acetate-malonate pathway [66]. ...
... Phlorotannins, a type of polyphenolic compound, are found exclusively in bro algae, and their quantity can vary among species, depending on factors such as algae s age, tissue type, salinity, season, nutrient levels, intensity of herbivory, light intensity, water temperature [67]. Similar to other polyphenols, phlorotannins have several rem able properties relevant to biological systems, including antioxidant [68], a Phlorotannins can be split into six distinct groups based on the type of structural connections between phloroglucinol units and the quantity of hydroxyl groups present: phlorethols and fuhalols (phlorotannins with an ether linkage), fucols (which present a phenyl linkage), fucophlorethols (with an ether and phenyl linkage), eckols (with a dibenzodioxin linkage), and carmalols [65]. In the event of cellular damage, these substances are produced via the acetate-malonate pathway [66]. ...
Polyphenols are beneficial natural compounds with antioxidant properties that have recently gain a lot of interest for their potential therapeutic applications. Marine polyphenols derived from marine macroalgae have been discovered to possess interesting antioxidant properties; therefore, these compounds can be included in several areas of drug development. Authors have considered the use of polyphenol extracts from seaweeds as neuroprotective antioxidants in neurodegenerative diseases. Marine polyphenols may slow the progression and limit neuronal cell loss due to their antioxidant activity; therefore, the use of these natural compounds would improve the quality of life for patients affected with neurodegenerative diseases. Marine polyphenols have distinct characteristics and potential. Among seaweeds, brown algae are the main sources of polyphenols, and present the highest antioxidant activity in comparison to red algae and green algae. The present paper collects the most recent in vitro and in vivo evidence from investigations regarding polyphenols extracted from seaweeds that exhibit neuroprotective antioxidant activity. Throughout the review, oxidative stress in neurodegeneration and the mechanism of action of marine polyphenol antioxidant activity are discussed to evidence the potential of algal polyphenols for future use in drug development to delay cell loss in patients with neurodegenerative disorders.
... In the pharmaceutical area, seaweeds' compounds have multi-role actions as anti-diabetic, anti-inflammatory, antimicrobial, antiviral, antiallergic, antidiabetic, antioxidant, antiphotoaging, antipruritic, hepatoprotective, hypotension, neuroprotective, tissue regeneration, and anticancer agents (Magalhães et al., 2011;Nwosu et al., 2011;Lopes, 2014;Im et al., 2017;Khalil et al., 2017;Murray et al., 2018;Mekinić et al., 2019;Cotas et al., 2020b;Valado et al., 2020). ...
... As marine organisms are exposed to extreme environmental conditions, they produce unique secondary metabolites, which have been recognized as important compounds for the development of innovative medicines. Part of the diversity of the oceans comes from algae, which constitute one of the most important groups of organisms, both in number and in diversity of species [2]. Macroalgae, that comprise a varied group of organisms, are eukaryotic, macroscopic and photosynthetic organisms and are among the largest oxygen producers on Earth [2]. ...
... Part of the diversity of the oceans comes from algae, which constitute one of the most important groups of organisms, both in number and in diversity of species [2]. Macroalgae, that comprise a varied group of organisms, are eukaryotic, macroscopic and photosynthetic organisms and are among the largest oxygen producers on Earth [2]. Currently, the use of macroalgae is relevant for different areas such as agriculture, aquaculture, food, cosmetics, pharmaceutical industry, and is also widely used as a source of gelling agents, phycocolloids, such as agar, which are usually used as thickeners, and stabilizers for suspensions and emulsions [3]. ...
... They include macroalgae with a wide range of sizes and shapes, from a few centimeters to tens of meters. The formation of seaweed forests are common, allowing efficient capture of sunlight and serving as habitat for many marine animals [2]. Of the approximately 2000 known species in this class, less than 1% live in fresh water [5]. ...
In the last decades, marine macroalgae have drawn attention mainly because of their bioactive constituents. Most brown algae are distributed over coastal areas of the Atlantic Ocean, Mediterranean Sea, Aegean Sea and Black Sea, and their composition varies with endogenous and exogenous factors. Phlorotannins, fatty acids, sterols and carbohydrates are some of the compounds responsible for biological activities related to cytotoxic, antiviral, antifungal, antibacterial, antidiabetic, antioxidant and anti-inflammatory potential. In this review we seek to highlight some of the compounds responsible for these last two biological activities, which have enormous importance for the management of neurodegenerative diseases, such as Alzheimer and Parkinson’s, with neuroinflammation and oxidative stress as hallmarks. However, one of the major problems associated with treating these diseases is the highly selective blood-brain-barrier, which can be overcome with nanocarriers used as delivery systems. Weighing the risks, benefits and toxicity of the used nanoparticles is nevertheless important. We also discuss zebrafish as an upcoming adequate biological model for in vivo screening of risks and benefits of such treatment strategies. This review aims to enable researchers working in the exploitation of these macroalgae and in the use of nanocarriers to potentiate the controlled delivery of bioactive compounds.
... Phytosterols are mainly found in the cellular membranes of plants and algae (Lopes et al., 2013). Algal sterols have a unique group that can be used as a chemotaxonomic biomarker to characterize the members of the three main algal divisions: Chlorophyceae (green algae), Rhodophyceae (red algae), and Phaeophycea (brownalgae) (Lopes, 2014). Generally, C29 sterols, namely fucosterol, and isofucosterol, are the major compounds in brown and green algae. ...
... Almost 98% of this isolate is supposed to comprise phenolic compounds while the rest of 2% would contain traces of fatty acids and carbohydrates. In the purification procedure (1) three washes with hexane remove non-polar components especially lipids, lipophilic compounds, and chlorophyll (2) three washes with dichloromethane remove lipids; (3) three washes with acetone followed by ethanol remove carbohydrates and proteins; acetone disturbs phlorotannins-proteins interactions and also hydrogen bonds between phlorotannin-protein complexes and (4) three ethyl acetate washes resulting in two fractions, an aqueous and an ethyl acetate fraction (Lopes, 2014;Gager et al. (2020); Klervi et al., 2016). Li et al. (2017) has noted the highest TPC (88.48 ± 0.30 mg PGE 100 mg − 1 extract) and the highest antioxidant activities in the ethyl acetate fraction compared to each solvent used for fractionating the extract. ...
... The present work reported significantly higher TPC in the ethyl acetate phase than that of S. vulgare ethyl acetate extract; 5.77 ± 0.33 mg GAE/ g as mentioned by Hidayati et al. (2019). The TPC in seaweeds is highly variable depending on factors, such as species, geographical origin, environmental conditions such as salinity, light and nutrient availability, harvest season, post-harvest processing and others (Lopes, 2014). This may explain the difference in the results among different works. ...
... Phloroglucinol was not effectively dissolving in the solvent at concentrations above 0.5 g/mL. According to Lopes (2014), Gram-positive microorganisms show relatively high susceptibility to the phlorotannins action; hence, this extract would be a potential remedy against Gram-positive microbial infections. Gramnegative microorganisms are less sensitive to phlorotannins' inhibitory effect due to the presence of a more complex cell wall with high lipopolysaccharide content. ...
Phlorotannins are a family of proven therapeutic agents. However, low stability disturbs their full bioactivity expression in the human body. Hence, this study focused on preserving their vitality through encapsulation. Phlorotannins isolated from Sargassum ilicifolium were encapsulated in the chitosan-tripolyphosphate carrier. Their storage stability, processing stability, and bioactivity retention upon in vitro digestion were determined. Results revealed the highest total phlorotannin content (TPC) of 854.38± 48 mg Phloroglucinol Equivalence/g in the semi-purified ethyl acetate fraction while the NMR spectrum and the LCMS profile revealed the isolation of phlorotannins in it. Storage at –18℃ and 4℃ temperatures preserved thrice both the encapsulated and non-encapsulated phlorotannins than ambient conditions. Encapsulated compound reported 56.4% of TPC retention at 175 ℃ processing temperature. Fermented fraction of encapsulated form showed significantly higher (p<0.05) antioxidant activities and TPC (0.23±0.03 mg/mL) suggesting the potential for targeted delivery of phlorotannins to their absorption sites through encapsulation.
... Seaweeds were widely analyzed by scientists during the past decades and their health promoting benefits have been identified (Scalbert et al., 2005). Literature reviews highlight several disease preventive attributes of sea weeds such as reduction of the risk of inflammation (Ibanez and Cifuentes, 2013), cardiovascular diseases (Kumar et al., 2008;Murray et al., 2018), diabetes (Celikler et al., 2009;Murray et al., 2018;Nwosu et al., 2011), microbial contamination (Lopes, 2014), neurodegenerative diseases (Barbosa et al., 2014). It delivers a multitude of functionalist ranging from a simple nutritional improvement to physiologically complex mechanisms. ...
Sargassum crassifolium is an edible brown-seaweed which contains many bioactive compounds. The study was developed to extract crude proteins using four different methods and determine the functional properties. SDS-PAGE was used to analyze the extracts and best methods were selected. Accordingly, water (1:3), salt (4%), alkaline (1:3) and ethanol (1:4) extractions were selected as the best methods to extract crude protein from S. crassifolium. Among them, salt extract showed the highest protein content (p<0.05). Each treatment has shown low intensity band patterns. Ethanol extract showed highest iron chelating and low oxidation levels. Salt extract showed higher DPPH activity while all extracts showed less antibacterial activity (p<0.05). Therefore, we can conclude that crude extracts from S. crassifolium showed effective free radical scavenging, metal chelating and low antibacterial activities.
... Seaweeds were widely analyzed by scientists during the past decades and their health promoting benefits have been identified (Scalbert et al., 2005). Literature reviews highlight several disease preventive attributes of sea weeds such as reduction of the risk of inflammation (Ibanez and Cifuentes, 2013), cardiovascular diseases (Kumar et al., 2008;Murray et al., 2018), diabetes (Celikler et al., 2009;Murray et al., 2018;Nwosu et al., 2011), microbial contamination (Lopes, 2014), neurodegenerative diseases (Barbosa et al., 2014). It delivers a multitude of functionalist ranging from a simple nutritional improvement to physiologically complex mechanisms. ...
Sargassum crassifolium is an edible brown-seaweed which contains many bioactivecompounds. The study was developed to extract crude proteins using four differentmethods and determine the functional properties. SDS-PAGE was used to analyzethe extracts and best methods were selected. Accordingly, water (1:3), salt (4%),alkaline (1:3) and ethanol (1:4) extractions were selected as the best methods toextract crude protein from S. crassifolium. Among them, salt extract showed thehighest protein content (p<0.05). Each treatment has shown low intensity bandpatterns. Ethanol extract showed highest iron chelating and low oxidation levels.Salt extract showed higher DPPH activity while all extracts showed lessantibacterial activity (p<0.05). Therefore, we can conclude that crude extracts fromS. crassifolium showed effective free radical scavenging, metal chelating and lowantibacterial activities.
... The totality of mentioned concepts refers to a term "functional food" which single out Q1 a specific group of components with potentials of providing benefits to human body regardless of its food source rudimentary features. Our planet surface is mainly covering its surface with oceans, studies on food sources available in oceans called "seaweed or marine sources" needs to be paid attention [2]. Regarding different environmental conditions, marine organisms behave in various ways to adopt each other which is accompanied with producing new secondary metabolites and bioactive constituents and thus nutritional components could uptake through nourishing, are in various range in classes of fatty acids (in form of poly unsaturated fatty acids (PUFAs), vitamin and mineral, antioxidant, bioactive components etc.) [3]. ...
Objectives
To review red algae bioactive compounds and their pharmaceutical applications.
Content
Seaweed sources are becoming attractive to be used in health and therapeutics. Among these red algae is the largest group containing bioactive compounds utilized in cosmetic, pharmaceutical, food industry, manure and various supplements in food formula. Various significant bioactive compounds such as polysaccharides (aginate, agar, and carrageenan), lipids and polyphenols, steroids, glycosides, flavanoids, tannins, saponins, alkaloids, triterpenoids, antheraquinones and cardiac glycosides have been reported in red algae. The red algae have rich nutritional components Different polysaccharides of red algae possess the antiviral potential namely agarans, carrageenan, alginate, fucan, laminaran and naviculan. Sulfated polysaccharides and carraginans of red algae are rich source of soluble fibers which can account for antitumor activities depending upon chemistry of various secondary metabolites and metabolism of cell line. Flavons-3-ols containing catechins from many red algae block the telomerase activity in colon cancer cells. Contraceptive agents were tested from red algae as a source for post-coital. Lectin of red algae showed pro-healing properties and anti-ulcerogenic activities. Carragenates from red algae also conferred a positive influence on diabetes. Red algae depicted a reducing effect on plasma lipids and obesity. Porphyran from red alga can act as anti-hyperlipidemic agent also reduces the apolipoprotein B100 via suppression of lipid synthesis in human liver.
Summary
The polyphenolic extracts of Laurencia undulate, Melanothamnus afaqhusainii and Solieria robusta extract show anti-inflammatory effects against multiple genera of devastating fungi. Antioxidants such as phlorotannins, ascorbic acids, tocopherols, carotenoids from red algae showed toxicity on some cancer cells without side effects. Red algae Laurencia nipponica was found insecticidal against mosquito larvae. Red algae fibers are very important in laxative and purgative activities. Gracilaria tenuistipitat resisted in agricultural lands polluted with cadmium and copper.
Outlook
In the recent decades biotechnological applications of red algae has been increased. Polysaccharides derived from red algae are important tool for formulation of drugs delivery system via nanotechnology.
... For example, polyphenols, which are present in algae as in most plant materials (Sanz-Pintos et al., 2017; Zehlila et al., 2017), are bioactive molecules considered as highly beneficial for human health, thanks to their ability to serve as antioxidants (Scalbert, Johnson, & Saltmarsh, 2005). Numerous studies highlight various disease preventive attributes of algal polyphenols such as reducing the risk of inflammation (Ibañez & Cifuentes, 2013), cancer (Lee et al., 2013;Plaza et al., 2008;Thomas & Kim, 2011), cardiovascular diseases (Kumar, Ganesan, Suresh, & Bhaskar, 2008;Murray, Dordevic, Ryan, & Bonham, 2018), diabetes (Celikler et al., 2009;Murray et al., 2018;Nwosu et al., 2011), allergy (Barbosa, Valentão, & Andrade, 2014), microbial contamination (Lopes, 2014) and neurodegenerative illnesses (Barbosa et al., 2014). The high affinity of polyphenols to proteins (Papadopoulou & Frazier, 2004) facilitates their co-extraction, and their presence in the protein extract may improve its health-promoting value. ...
With rising global population and decreasing available land and fresh water resources, the oceans provide an attractive domain for sourcing nutrients. The marine macroalgae Ulva sp. and Gracilaria sp. are candidate raw biomass. Ulva sp. has high growth rate and Gracilaria sp. has high protein content and their seasonal growth is complementary, allowing almost year-round high yield protein production. In this study, we aimed at developing an effective process, to yield a high macroalgae protein content concentrate suitable for food application, and studying the digestibility, amino acid composition and antioxidant properties of the obtained algal protein concentrates (APCs). We developed a new protein extraction protocol, and compared it to several published protocols. The developed protocol is food-grade, and yielded APC from Ulva and form Gracilaria, containing 70 and 86% protein respectively. The amino acid compositions of the APCs suggest their possible use as sources of essential amino acids. Simulated gastro-intestinal digestion showed that APCs proteolysis of at least 89% can be reached. We found that the APCs exhibit antioxidant activity, which is similar to that of known protein isolates in the hydrogen atom transfer mechanism, but 10 to 20 times higher in the single electron transfer mechanism. These results suggest that polyphenolic compounds might be still present in the APCs and contribute to their antioxidant activity. Our results suggest that the protein concentrates extracted from Ulva sp. and Gracilaria sp. seem to be promising sustainable sources for human nutrition thanks to their essential amino acids content, digestibility and antioxidant properties.
... Tannins are abundant in different plant species and brown seaweeds, where they are part of the protection against plant infections, herbivores and oxidative stress. Plant tannins can be classified in two groups: condensed and hydrolyzable tannins, while in seaweeds, they consist in phlorotannins made by polymerization of phloroglucinol units [41,71]. These polyphenols are known to complex with proteins through nonspecific forces such as hydrogen bonding and hydrophobic effects, as well as by covalent bond formation. ...
The increased incidence of fungal infections, associated with the widespread use of antifungal drugs, has resulted in the development of resistance, making it necessary to discover new therapeutic alternatives. Among fungal infections, dermatophytoses constitute a serious public health problem, affecting 20–25 % of the world population. Medicinal plants represent an endless source of bioactive molecules, and their volatile and non-volatile extracts are clearly recognized for being the historical basis of therapeutic health care. Because of this, the research on natural products with antifungal activity against dermatophytes has considerably increased in recent years. However, despite the recognized anti-dermatophytic potential of natural products, often advantageous face to commercial drugs, there is still a long way to go until their use in therapeutics. This review attempts to summarize the current status of anti-dermatophytic natural products, focusing on their mechanism of action, the developed pharmaceutical formulations and their effectiveness in human and animal models of infection.
