Brown Algae Research Articles

A cry for kelp: Evidence for polyphenolic inhibition of Oxford Nanopore sequencing of brown algae.

Genomic resources have yielded unprecedented insights into ecological and evolutionary processes, not to mention their importance in economic and conservation management of specific organisms. However, the field of macroalgal genomics is hampered by difficulties in the isolation of suitable DNA. Even when DNA that appears high quality by standard metrics has been isolated, such samples may not perform well during the sequencing process. We here have compared Oxford Nanopore long-read sequencing results for three species of macroalgae to those of nonmacroalgal species and determined that when using macroalgal samples, sequencing activity declined rapidly, resulting in reduced sequencing yield. Chemical analysis of macroalgal DNA that would be considered suitable for sequencing revealed that DNA derived from dried macroalgae was enriched for polyphenol-DNA adducts (DNA with large polyphenols chemically attached to it), which may have led to sequencing inhibition. Of note, we observed the strongest evidence of sequencing inhibition and reduced sequence output when using samples dried using silica gel-suggesting that such storage approaches may not be appropriate for samples destined for Oxford Nanopore sequencing. Our findings have wide-ranging implications for the generation of genomic resources from macroalgae and suggest a need to develop new storage methods that are more amenable to Oxford Nanopore sequencing or to use fresh flash-frozen tissue wherever possible for genome sequencing.

Exploration of an efficient and universal extraction strategy for fucoidan with glycolipid-lowering activity from typical brown algae: The importance of ball milling combined with acid treatment

Fucoidan possesses a variety of biological activities beneficial for human wellness. It is a good candidate for ameliorating obesity and diabetes. However, high-purity fucoidan products are limited due to the co-extraction of impurities i.e. alginate, protein and small molecular substances. In this study, the optimal preparation strategy for high-purity fucoidan from a template brown alga (Saccharina japonica) was screened out by the exploration of key and auxiliary steps. The key step was confirmed as moderate-temperature acid extraction and the auxiliary steps were fixed on ethanol refluxing and ball milling pretreatment. The fucose content of S. japonica fucoidan increased by 7.15 times and the sulfate group content increased by 4.87 times compared with those of fucoidans prepared by classic high-temperature acid extraction. Ball milling-assisted moderate-temperature acid extraction performed great effectiveness and universality in the extraction of high-purity fucoidans derived from four brown algae including S. japonica, Undaria pinnatifida, Sargassum fusiforme, and Fucus vesiculosus. Glycolipid-lowering activities of four fucoidans were confirmed by their interactions with intestinal bile acid, cholesterol micellar, glucose and probiotics including butyrate-producing bacteria, Bacteroides, Bifidobacterium, and Lactobacillus. Our study provided an efficient and universal extraction process for high-purity fucoidan with glycolipid-lowering activity from typical brown algae.

4-Hydroxydictyolactone alleviates cerebral ischemia injury by regulating neuroinflammation and autophagy via AMPK signaling pathway

BackgroundCerebral ischemia (CI), a cerebrovascular disorder, is a major contributor to disability and mortality. Marine-derived compounds are an important source of new neuroprotective drug candidates. Xenicane-type diterpenes from brown algae of the genus Dictyota have exhibited potential neuroprotective effects against CI injury, attributed to their antioxidant properties. However, whether there are other underlying neuroprotective mechanisms of xenicane diterpenes against CI is still ambiguous. PurposeThis study aims to elucidate the neuroprotective efficacy and mechanism of 4-hydroxydictyolactone (HDTL) in the treatment of CI. MethodsThe LPS-induced BV2 cell model was used for anti-neuroinflammatory activity assay. Tandem Mass Tag (TMT)-based quantitative proteomics was employed to identify underlying mechanisms. The OGD/R-induced SH-SY5Y cell model and a MCAO mice model were used to assess the neuroprotective effect of HDTL against CI in vitro and in vivo. ResultsHDTL reduced inflammation in LPS-stimulated BV2 cells by inhibiting the IKK/IκB/NF-κB pathway and by enhancing AMPK phosphorylation. Additionally, in SH-SY5Y cells treated with OGD/R, HDTL facilitated autophagy and reduced apoptosis. The neuroprotective properties of HDTL were abrogated in AMPK- silenced SH-SY5Y cells. In MCAO mice, HDTL ameliorated CI injury as evidenced by decreases in neurological deficit scores and cerebral infarction. HDTL also promoted autophagy and reduced apoptosis in vivo through both the AMPK/mTOR and IKK/IκB/NF-κB pathways. ConclusionHDTL exhibits neuroprotective effects through regulating the AMPK/mTOR and IKK/IκB/NF-κB pathways. These findings suggest that HDTL is a promising therapeutic candidate for CI treatment.

Investigating the Sway of Marine Brown Seaweed Gel as Natural Polymer in Properties of Concrete

In the present study, the effects of the fresh properties as slump, consistency and setting time and hardened concrete's characteristics such as compressive, split tensile and flexural strength for various ages, the brown seaweed (Sargassum wightii) gel was added to cement throughout differing proportions (1, 2, 3, 4 and 5%) by the mass of concrete. Durability and thermal tests such as water absorption, sorptivity, RCPT, acid attack and thermal conductivity also determined at various ages. Micro structural properties of seaweed gel were found out by SEM, FTIR and XRD analysis. Test results show that seaweed gel act as retarding admixture in cement up to 5% of addition. For instance, 5% alginate collections as a percentage of concrete mass showed a comparable compressive strength of about 42MPa. The use of seaweed gel improved the thermal characteristics of concrete by reducing its thermal conductivity roughly 50% for a 5% addition. The seaweed gels up to 5% addition in concrete will significantly improve the fresh-state properties of concrete without affecting its hardened properties. The future is completely dependent on eco-friendly materials; hence the use of natural organic additives to improve the strength and durability of cement concrete would be the better option for sustainability.

Seaweed-derived etherified carboxymethyl cellulose for sustainable tissue engineering

Biodegradability, biocompatibility, abundant supply from renewable sources, and affordability are the outstanding properties of cellulose that have prompted substantial studies into its potential in biomedical applications. Beyond terrestrial sources of cellulose, seaweeds have attracted much attention as a potential source of cellulose because they are widely available. Cellulose and its byproducts may be extracted from various macroalgae species, including red, green, and brown algae. The extracted cellulose's qualities vary depending on the algae species, age, and extraction process utilized. Cellulose's characteristics are enhanced through chemical modifications, specifically etherification and esterification, which substitute functional groups for hydroxyl groups, yielding a range of products, including cellulose acetate (CA), cellulose nitrate, cellulose sulfate, methylcellulose, and carboxymethyl cellulose (CMC). The ability to modify CMC characteristics for particular applications is explored through techniques including grafting processes mixing, and cross-linking with other polymers. Moreover, tissue engineering is given significant consideration in the growing use of CMC and its altered forms in biological applications. These alterations allow for the production of scaffolds that promote tissue regeneration and cell proliferation, enabling CMC-based scaffolds for various tissue engineering uses. This review provides a comprehensive overview of CMC's properties, modifications, and potential in tissue engineering.

Secular change in seaweed species composition and coverage of Sargassaceae on the artificial reef in Wakasa Bay, Japan.

The threat of declining seaweed beds has been a concern around the world. Seagrass and seaweed (brown algae) beds are essential habitats supporting fisheries. However, approximately 22% of these habitats have been lost in Japan due to increased coastal landfill sites and ports. This study aims to rehabilitate the depletion of these habitats by constructing an artificial reef in Wakasa Bay, Japan, and monitoring Sargassaceae succession in the second and fourth years after the construction was completed. In this study, we set up four sites on the artificial reef. Then we identified the seaweed species composition and coverage of the Sargassaceae using underwater visual observation by scuba divers. The seaweed coverage was already over approximately 80% in the second year after construction. The Sargassum horneri and S. confusum dominated during the first and second sampling in the second year after construction, and Myagropsis myagroides and S. patens during the third and fourth sampling in the fourth year after construction. Thus, the recovery of species composition takes longer than that of coverage. Therefore, observing species composition recovery is essential when constructing the artificial reef.

Seven undescribed meroterpenoids from Sargassum siliquastrum and their inhibitory activity against amyloid β aggregation.

The inhibition of amyloid β (Aβ) aggregation and degradation of Aβ aggregates are promising approaches for treating and preventing Alzheimer's disease. In our search for Aβ42 aggregation inhibitors, we isolated seven undescribed meroterpenoids, sargasilides A (1)‒G (7), from brown alga (Sargassum siliquastrum) collected at Noto Peninsula in Japan. We structurally elucidated the isolated meroterpenoids using spectroscopic data and evaluated their activities using Thioflavin T assay and transmission electron microscopy. Among the seven compounds isolated, sargasilide B had the strongest inhibitory activity. From the comparison of structure and activity, the geometric isomerism of olefins and length of isoprene side chains are important for the activity of meroterpenoids isolated from brown alga.

Investigating the Inhibitory Effect of Sargassum natans and Sargassum fluitans Extracts on Iron Corrosion in 1.00 mol L−1 HCl Solution

This study deals with the efficacy of extracts of Sargassum natans and Sargassum fluitans, an invasive brown algae present in Guadeloupe, as novel and environmentally friendly corrosion inhibitors for iron in 1 mol L−1 hydrochloric acid solutions. Six different Sargassum extracts (SE) were obtained using Soxhlet extraction with ethyl acetate, acetone, and ethanol, respectively, as solvents; cold successive maceration with chloroform and methanol, respectively; and microwave-assisted extraction with water. Subsequent electrochemical analysis showed that extracts from ethanol and ethyl acetate exhibited remarkable inhibition efficiencies of, respectively, 72.6% and 70.2%, but the better one was the extract of the cold maceration from chloroform with an inhibition efficiency of 92.0%. These findings allow us to focus on the chloroform extract (SEd) in order to see the change happening during the corrosion process via SEM and EDX analyses. Also, NMR analysis was conducted to identify the main chemicals responsible for the anticorrosion effect. The successful demonstration of the corrosion inhibitor effectiveness of extracts of Sargassum natans and fluitans suggests a potentially valuable use for this invasive biomass. These encouraging results warrant further investigation to identify and elucidate the active inhibitors in these extracts to deepen our understanding of their mechanisms for corrosion prevention and potentially expand their utility as an environmentally conscious approach to corrosion control.

Influence of brown algae filler and process parameters on the surface roughness and MRR of jute fiber polymeric composite machined by abrasive water jet

Traditional manufacturing of polymeric composite leads to delamination. Implementing abrasive water jet machining (AWJM) presents a sustainable solution for shaping the polymeric composites, thereby eliminating the need to dispose of chemically contaminated waste. Brown microalgae, commonly found in aquatic environments, serve as viable additives for enhancing the properties of polymeric composites. This study entails the polymeric composite reinforced with jute fiber fabricated by modulating the weight percentages of brown algae powder by 0, 3, and 6 wt.% utilizing the hand layup procedure. The composites were formed and subsequently subjected to drilling by AWJ machining filled with brown algae. The experimental investigation was done to analyze the effect of AWJ parameters: water jet pressure (WJP), traverse speed (TS), and stand-off distance (SoD)—on the material removal rate (MRR) and average surface roughness ( Ra). Orthogonal Array L27 experimental results revealed that polymeric composite reinforced with jute fiber containing 3 wt.% of brown algae exhibited the highest MRR, with an increase of up to 12% compared to other samples. Additionally, these composites demonstrated a significant reduction in surface roughness, reaching up to 8% when compared to alternative samples. Utilizing the Taguchi-based ANOVA method facilitated a systematic exploration and identification of influential factors impacting both MRR and Ra in AWJ machining. Notably, the WJP and SoD emerged as key factors significantly influencing both MRR and Ra.

Chemical synthesis of a trisaccharide fragment of a fucosylated glucuronomannan isolated from brown algae

Fucose is abundant in marine organisms, primarily as fucoidan and fucosylated chondroitin sulfate. Our previous study characterized a sulfated and fucosylated glucuronomannan (SFGM) isolated from marine brown algae, exhibiting notable antiviral activity and potential for drug development. Herein, a trisaccharide fragment of this SFGM in the form of [α-L-Fuc(2, 4-diS)]-(1→3)-α-D-Man-(1→4)-α-D-GlcA-OMP was synthesized for the first time. Stereoselective formation of the α-1,2-cis-fucosidic bond was achieved by leveraging solvent effects. The sulfated trisaccharide as the final product, featuring a 2,4-diS-fucose unit and the p-methoxyphenyl group as a pendant at the anomeric position, was successfully accomplished. The synthetic strategy developed in this study offers a foundation for the pharmaceutical development of these SFGM oligosaccharides.

Candidate genes involved in biosynthesis and degradation of the main extracellular matrix polysaccharides of brown algae and their probable evolutionary history

BackgroundBrown algae belong to the Stramenopiles phylum and are phylogenetically distant from plants and other multicellular organisms. This independent evolutionary history has shaped brown algae with numerous metabolic characteristics specific to this group, including the synthesis of peculiar polysaccharides contained in their extracellular matrix (ECM). Alginates and fucose-containing sulphated polysaccharides (FCSPs), the latter including fucans, are the main components of ECMs. However, the metabolic pathways of these polysaccharides remain poorly described due to a lack of genomic data.ResultsAn extensive genomic dataset has been recently released for brown algae and their close sister species, for which we previously performed an expert annotation of key genes involved in ECM-carbohydrate metabolisms. Here we provide a deeper analysis of this set of genes using comparative genomics, phylogenetics analyses, and protein modelling. Two key gene families involved in both the synthesis and degradation of alginate were suggested to have been acquired by the common ancestor of brown algae and their closest sister species Schizocladia ischiensis. Our analysis indicates that this assumption can be extended to additional metabolic steps, and thus to the whole alginate metabolic pathway. The pathway for the biosynthesis of fucans still remains biochemically unresolved and we also investigate putative fucosyltransferase genes that may harbour a fucan synthase activity in brown algae.ConclusionsOur analysis is the first extensive survey of carbohydrate-related enzymes in brown algae, and provides a valuable resource for future research into the glycome and ECM of brown algae. The expansion of specific families related to alginate metabolism may have represented an important prerequisite for the evolution of developmental complexity in brown algae. Our analysis questions the possible occurrence of FCSPs outside brown algae, notably within their closest sister taxon and in other Stramenopiles such as diatoms. Filling this knowledge gap in the future will help determine the origin and evolutionary history of fucan synthesis in eukaryotes.

Chemical Survey and Antifungal Efficacy of Sargassum muticum's Alkaloids and Phenolic-Rich Fraction Against Airborne Toxigenic and Nosocomial Opportunistic Molds Isolates.

The Atlantic coastline of El-Jadida, Morocco, is renowned for its plentiful algae, especially brown seaweed, which is rich in active compounds known for their antifungal properties. This valuable resource offers an exciting opportunity to tackle the numerous challenges posed by invasive fungal infections, allergies, mycotoxin-related food poisoning, and drug-resistant strains. Underscoring the urgent need to explore alternative, sustainable, and environmentally friendly antifungal agents derived from algae. This study aimed to evaluate the antifungal activity of total alkaloids and phenolic-rich fractions derived from seven species of Pheophyceae: Sargassum muticum, Sargassum vulgare, Bifurcaria bifurcata, Cystoseira tamariscifolia, Cystoseira humilis, Laminaria ochroleuca, and Fucus spiralis against four fungi: airborne toxigenic isolates of Aspergillus westerdijkiae and Chaetomium globosum as well as nosocomial opportunistic isolates of Aspergillus nidulans and Scopulariopsis brevicaulis. The study also aimed to identify the most effective alga and its specific active compounds through LC-MS and GC-MS analysis. The invasive Sargassum muticum was chosen as the most potent alga in inhibiting the growth of mycelium. For the first time, the alkaloids palmatine and jatrorrhizine, along with caulerpin, have been identified. The chloroform fraction revealed the prevalence of phenolic compounds including, phenolic acids, flavonoids, and phlorotannins. The lowest minimum inhibitory concentrations (MICs), with a maximum fungal load of 108 colony-forming unit (CFU), recorded ranged from 3.12 to 6.25μg/mL by the phenolic-rich fraction against airborne toxigenic isolates, and from 100 to 200μg/mL against nosocomial opportunistic isolates by the total alkaloids. In comparison, the positive control, ketoconazole, showed higher MICs and resistance against A. nidulans. The valorization of Sargassum muticum is proposed as a green strategy to preserve the ecological balance, combat antifungal resistance, and address public health challenges.

Characterization of Unfractionated Polysaccharides in Brown Seaweed by Methylation-GC-MS-Based Linkage Analysis.

This study introduces a novel approach to analyze glycosidic linkages in unfractionated polysaccharides from alcohol-insoluble residues (AIRs) of five brown seaweed species. GC-MS analysis of partially methylated alditol acetates (PMAAs) enables monitoring and comparison of structural variations across different species, harvest years, and tissues with and without blanching treatments. The method detects a wide array of fucose linkages, highlighting the structural diversity in glycosidic linkages and sulfation position in fucose-containing sulfated polysaccharides. Additionally, this technique enhances cellulose quantitation, overcoming the limitations of traditional monosaccharide composition analysis that typically underestimates cellulose abundance due to incomplete hydrolysis of crystalline cellulose. The introduction of a weak methanolysis-sodium borodeuteride reduction pretreatment allows for the detection and quantitation of uronic acid linkages in alginates.

Сравнительное исследование элементов и биохимических компонентов стерильных и фертильных бурых водорослей Ascophyllum nodosum

Brown algae are a valuable renewable bioresource and are also important organisms to monitor due to anthropogenic impacts in the Arctic. In both cases, the content of natural elements and their potential seasonal variations are important knowledge for developing a monitoring program and planning biomass collection. The purpose of this work was a comparative study of the influence of the reproductive phase and biochemical characteristics on the elemental composition of Ascophyllum nodosum from the Barents Sea, the Irminger Sea and the Norwegian Sea. The content of polysaccharides (alginic acid, laminaran, fucoidan and mannitol) and 12 elements was studied. It was shown that the content of Fe, Al, Co, Cu correlates significantly in pairs, regardless of the presence of receptors in algae (r = 0.71–0.95, p < 0.05). It has been shown that the content of alginic acid significantly correlates with Co, Ca, Cu, As, Rb (r = –0.95, –0.89, –0.89, –0.88, –0.81, p ˂ 0.05, respectively) in sterile algae A. nodosum. Also for sterile individuals, a direct correlation of mannitol with Ca, Cu, Co, Rb, Sr, Al, Ba, Fe, Mn was noted (r = 0.98, 0.95, 0.93, 0.92, 0.91, 0.89, 0.82, 0.78, 0.76, р ˂ 0.05, respectively) and polyphenols with Zn (r = 0.94 at р ˂ 0.05) and As (r = 0.85 at р ˂ 0.05). For the first time, a direct correlation between the accumulation of alginic acid and fucoidan has been revealed for A. nodosum from the Arctic seas, which is not associated with the reproductive phase of the algae.

Ecophysiological responses of Fucus virsoides (Phaeophyceae, Fucales) to past and present nutrient conditions in the northern Adriatic

Fucus virsoides is a brown seaweed endemic to the Adriatic and the only species of its genus found in the Mediterranean. Historically widespread from the Venice lagoon (Italy) to Albania, this species has suffered a sharp decline and is currently threatened with extinction.Over the past three decades, the northern Adriatic has seen a shift towards oligotrophy conditions, yet the ecophysiology of F. virsoides in response to nutrients changes has been poorly studied. Addressing this gap is crucial for understanding the extent to which these environmental changes may have contributed to the species’ decline.To test our hypothesis that nutrient changes might be the primary driver of F. virsoides decline, we conducted a two-week experiment exposing germlings and adults to six different nutrient conditions. These included three Redfield ratios recorded in the Gulf of Trieste in 1996, 2007 and 2017, reflecting the shift from eutrophic to oligotrophic conditions experienced by F. virsoides in the wild. Additionally, the adults were exposed to three supplementary eutrophic conditions (naturally and artificially fertilized).Growth and physiological responses (measured via O2 evolution and PAM fluorimetry) of F. virsoides to varying nutrient conditions were largely consistent, with only subtle effects observed. Our results highlight the species’ acclimatation potential, suggesting that short-term nutrient changes alone may not fully explain its decline. Understanding F. virsoides resilience to multiple environmental stressors is crucial for developing effective conservation strategies to preserve marine forests in the face of ongoing anthropogenic disturbances.

Investigating the Anti-Inflammatory Activity of Various Brown Algae Species.

This literature review investigated the anti-inflammatory properties of brown algae, emphasizing their potential for dermatological applications. Due to the limitations and side effects associated with corticosteroids and immunomodulators, interest has been growing in harnessing therapeutic qualities from natural products as alternatives to traditional treatments for skin inflammation. This review explored the bioactive compounds in brown algae, specifically looking into two bioactive compounds, namely, fucoidans and phlorotannins, which are widely known to exhibit anti-inflammatory properties. This review synthesized the findings from various studies, highlighting how these compounds can mitigate inflammation by mechanisms such as reducing oxidative stress, inhibiting protein denaturation, modulating immune responses, and targeting inflammatory pathways, particularly in conditions like atopic dermatitis. The findings revealed species-specific variations influenced by the molecular weight and sulphate content. Challenges related to skin permeability were addressed, highlighting the potential of nanoformulations and penetration enhancers to improve delivery. While the in vivo results using animal models provided positive results, further clinical trials are necessary to confirm these outcomes in humans. This review concludes that brown algae hold substantial promise for developing new dermatological treatments and encourages further research to optimize extraction methods, understand the molecular mechanisms, and address practical challenges such as sustainability and regulatory compliance. This review contributes to the growing body of evidence supporting the integration of marine-derived compounds into therapeutic applications for inflammatory skin diseases.

Encapsulation of Phloroglucinol from Rosenvingea intricata Macroalgae with Zinc Oxide Nanoparticles against A549 Lung Cancer Cells

Background/Objectives: Phloroglucinol (PHL), a phenolic compound extracted from the brown alga Rosenvingea intricata, exhibits potent antioxidant and anticancer properties. This study aims to extract, purify, and characterize PHL, and further develop functionalized zinc oxide nanoparticles (ZnO NPs) loaded with PHL to enhance its therapeutic potential. Methods: PHL was extracted using acetone and purified through Sephadex LH-20 column chromatography, yielding a highly enriched fraction (F-3). The purified compound was characterized by FTIR, HPLC, NMR, and LC-MS. ZnO NPs were synthesized, PEGylated, and conjugated with PHL, forming ZnO-PEG-PHL NPs. Their characterization included DLS, zeta potential, XRD, SEM-EDAX, and encapsulation efficiency studies. Antioxidant assays (DPPH, FRAP, ABTS, RPA) were performed and in vitro cytotoxicity on A549 lung cancer cells were determined to evaluate the therapeutic efficacy of PHL. Results: The purified PHL fraction showed a high phenolic content (45.65 PHL mg/g), which was was confirmed by spectral analysis. The ZnO-PEG-PHL NPs increased in size from 32.36 nm to 46.68 nm, with their zeta potential shifting from −37.87 mV to −26.82 mV. The antioxidant activity was superior for the ZnO-PEG-PHL NPs in all assays, while the in vitro cytotoxicity tests showed an IC50 of 40 µg/mL compared to 60 µg/mL for the ZnO NPs and 70 µg/mL for PHL. Apoptotic studies revealed significant cell cycle arrest and apoptosis induction. Conclusions: The synthesized ZnO-PEG-PHL NPs demonstrated enhanced antioxidant and anticancer properties, making them promising candidates for cancer therapy and antioxidant applications.

Protein extraction from the industrial solid residue of brown seaweed after alginate extraction

The growing interest in the “blue-bioeconomy” and the valorization of macroalgae has driven research and industrial efforts to develop valorization strategies for the by-products generated during alginate extraction. Sequential extraction methods, such as acid/alkali treatment, enzymatic, ultrasound, and pH-shift process, were investigated and compared in order to obtain protein extracts from the solid residues after alginate extraction from two brown seaweed species (Ascophyllum nodosum and Saccharina latissima). Applying a sequential extraction, combining several methods, allowed the recovery of more than 29.5 % of the total protein from the residues. The resulting extracts exhibited optimal functional properties in terms of oil and water retention and outstanding emulsifying and foaming capacity. In addition, the protein extracts showed considerable polyphenol content, remarkable antioxidant activity, and an enhanced ability to inhibit angiotensin-converting enzyme (ACE). This study demonstrated that the residues after alginate extraction are a sustainable and promising source of protein with potential applications in the food industry.

Характеристика антиоксидантной активности СО2- экстрактов бурых водорослей и стабилизации липидов

Vegetable oils are susceptible to oxidation during storage, which is a serious problem for shelf-life and food safety. The article describes the antioxidant properties of supercritical extracts from brown algae (Undaria pinnatifida and Costaria costata), Russian Far East. It also explains their prospects as stabilizers that preserve the quality and safety of vegetable oils by affecting the kinetics of oxidation and hydrolysis. The study featured supercritical extracts of marine brown algae Undaria pinnatifida and Costaria costata from Russian Far East. The methods involved spectrophotometry and high-performance liquid chromatography. Supercritical extracts of marine brown algae proved to be reliable sources of bioactive substances, e.g., phenolic compounds, carotenoids, and mannitol. They also possessed antioxidant properties in terms of antiradical activity, hydroxyl ion binding, superoxide radical absorption, and Fe+2 chelating. The experiments revealed nine phenolic compounds responsible for antioxidant properties. The supercritical extract of Costaria costata demonstrated a greater antioxidant effect on lipid oxidation in vegetable oils than Undaria pinnatifida. Both algae proved effective in stabilizing hydrolysis and were able to increase the shelf-life of soy and sunflower oils by three months. Supercritical extracts of Undaria pinnatifida and Costaria costata served as antioxidants to stabilize lipid oxidation in refined and unrefined soy and sunflower oils. The research revealed high approximation coefficients for regression equations describing the patterns of changes in the peroxide and acid numbers of vegetable oils stabilized with supercritical extracts of these marine brown algae.

Experimentation on Sargassum wightii as a flash powder igniter for attaining eco-friendly combustion on pyrotechnics

Firecrackers are a vital element of cultural festivities that happen worldwide. However, the hazardous by-products they emit have a significant impact on environmental pollution, leading to the greenhouse effect and climate change. Aluminium powder serves as the fuel in the traditional flash powder mixture, nitrate of potassium serves as an oxidizing agent, and sulphur acts as the igniter at exact concentrations. The presence of sulfur in the flash powder mixture is critical as it acts as an igniter, contributing to the formation of sulfur dioxide, which can cause environmental harm. We carried out an experiment employing Sargassum wightii brown seaweed powder as a replacement for sulphur at specific amounts to lessen the effects of sulphur in flash powder. We discovered that Sargassum wightii brown seaweed powder may replace up to 50% of the sulphur significance in the flash powder mixture without impairing the flash powder's traditional performance. Our experiments included impact and friction sensitivity, SEM, and FTIR analyses to evaluate the improved flash powder composition. The results revealed that the modified flash powder mixture SP5 and SP10 emits less emission by 12% and 21%, and produces similar noise performance of 108 and 107 dB(A) to the normal flash powder composition (SP), affirming that the SP10 flash powder is a viable alternative. Moreover, in our relentless pursuit to mitigate the detrimental effects on our environment, we have ingeniously introduced a novel product—the Chinese cracker made from vegetable waste paper. Not only does this innovative solution address concerns regarding land pollution, but it also presents a sustainable approach to consumer goods.