Abstract
The proximate compositions of seaweeds, namely Sargassum boveanum, Padina gymnospora, and Dictyota dichotoma, were analyzed. The dried powder was further extracted via ethanol, acetone, ethyl acetate, and chloroform, and the phenolic and flavonoid contents of the extracts were determined. The ethanolic extracts presented greater yields than the other solvents did, and the values ranged from 5.1±0.9 to 25.2±1.3, 2.2±0.4 to 35.3±1.1, and 3.3±0.5 to 20.6±1.2, for S. boveanum, P. gymnospora, and D. dichotoma, respectively. The highest total flavonoid and phenolic contents were found in the ethyl acetate extract of P. gymnospora, with values of 91.5±1.2 mg QE/g and 178.3±1.1 mg GAE/g, respectively. The 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging assay, ferric reduction activity powder (FRAP) assay, and ABTS method were used. The ethyl acetate extract of P. gymnospora presented the maximum DPPH activity (65.3±1.1 TE/g), whereas the ethanol extract presented 27.6±0.5 AAE/g in the FRAP assay, and the ethyl acetate extract presented 37.3±0.8 TE/g activity. The ethyl acetate extract of P. gymnospora presented higher α-amylase inhibitory activity (0.28±0.04 mg/mL), whereas the ethanol extract of S. boveanum presented higher α-glucosidase inhibitory activity (0.31±0.02 mg/mL). The maximum human red blood cell protection activity (43.7±1.2%) and cyclooxygenase enzyme -2 inhibition(37.1±0.2%) activity were observed in the ethyl acetate fraction of S. boveanum.
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Proximate Composition and Antioxidant Property, Anti-inflammatory and Anti-Diabetic Efficacies of Brown Seaweed Extracts
Mansour K. Gatasheh 
*
The proximate compositions of seaweeds, namely Sargassum boveanum, Padina gymnospora, and Dictyota dichotoma, were analyzed. The dried powder was further extracted via ethanol, acetone, ethyl acetate, and chloroform, and the phenolic and flavonoid contents of the extracts were determined. The ethanolic extracts presented greater yields than the other solvents did, and the values ranged from 5.1±0.9 to 25.2±1.3, 2.2±0.4 to 35.3±1.1, and 3.3±0.5 to 20.6±1.2, for S. boveanum, P. gymnospora, and D. dichotoma, respectively. The highest total flavonoid and phenolic contents were found in the ethyl acetate extract of P. gymnospora, with values of 91.5±1.2 mg QE/g and 178.3±1.1 mg GAE/g, respectively. The 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging assay, ferric reduction activity powder (FRAP) assay, and ABTS method were used. The ethyl acetate extract of P. gymnospora presented the maximum DPPH activity (65.3±1.1 TE/g), whereas the ethanol extract presented 27.6±0.5 AAE/g in the FRAP assay, and the ethyl acetate extract presented 37.3±0.8 TE/g activity. The ethyl acetate extract of P. gymnospora presented higher α-amylase inhibitory activity (0.28±0.04 mg/mL), whereas the ethanol extract of S. boveanum presented higher α-glucosidase inhibitory activity (0.31±0.02 mg/mL). The maximum human red blood cell protection activity (43.7±1.2%) and cyclooxygenase enzyme -2 inhibition(37.1±0.2%) activity were observed in the ethyl acetate fraction of S. boveanum.
DOI: 10.15376/biores.21.2.5041-5056
Keywords: Seaweeds; Biomass; Bioreserve; Antioxidant; Anti-diabetic; Anti-inflammatory
Contact information: Department of Biochemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; *Corresponding author: mgatasheh@ksu.edu.sa
Graphical Abstract
INTRODUCTION
There are more than 15,000 seaweed species, and these have been widely used in several countries. They have been applied in Asian countries for medicine and food (Pérez-Lloréns et al. 2020). Seaweed has gained much more attention in recent years in several industries, including pharmaceuticals, because of their excellent industrially viable applications in food, textiles, and cosmetics (Janarthanan and Senthil Kumar 2018; Lomartire and Gonçalves 2022). They are used as laxatives, antimicrobial agents, and antiulcer agents owing to their potential as pharmaceutical compounds (Mendes et al. 2010). In addition, seaweeds are rich in several nutrients, including vitamins, proteins, and minerals (Mac Monagail et al. 2017). Secondary metabolites, which are extracted from seaweeds, are utilized by pharmaceutical industries and are considered a major nutrient reserve. Seaweeds present various colors and have bioactive potential. These include antifungal, antibacterial, anticancer, and antioxidant activities (Mutalipassi et al. 2021). In seaweed, macromolecules and phytochemicals such as antioxidant enzymes, carotenoids, polyphenols, tocopherols, ascorbic acid and several other molecules exhibit antioxidant activity (Mutalipassi et al. 2021). The seaweed is also rich in minerals (iron, iodine, copper, and calcium), polysaccharides (alginate, agar‒agar, and carrageenan), proteins, lipids, amino acids, and polyunsaturated fatty acids (Safafar et al. 2015; Schmid et al. 2018; Raja et al. 2022). Seaweeds are rich in vitamins, phlorotannins, flavonoids, bromphenols, and phenolic compounds. In addition, the availability of water-soluble and fat-soluble vitamins reduces the incidence of atherosclerosis, thrombosis, and cardiovascular diseases (Morais et al. 2020; Ferdous and Balia Yusof 2021).Seaweeds are rich in carotenoids and phenolic compounds that neutralize the free radicals in seaweeds, downregulate oxidative stress and prevent various degenerative diseases (Lobo et al. 2010).The development of these complications is associated with the progression of oxidative stress, which induces the development of free radicals and affects several metabolic pathways (Daoudi et al. 2022). Anti-diabetic drugs have been used to control blood sugar levels and maintain homeostasis, and these drugs have serious side effects.
Current epidemiological evidence reveals that diabetes affects more than 463 million people worldwide, and the estimated number of cases may be approximately 700 million by 2045. Diabetes is broadly classified into Type 1 and Type 2.Type 2 is the most common type of diabetes among individuals. Diabetes mellitus causes severe complications and affects the animal vascular system. Diabetes can induce microvascular complications (microangiopathy) and macrovascular complications (macroangiopathy) (Deshpande et al. 2008). Seaweeds are considered to maintain the balance of sugar metabolism in animals. The side effects of drugs vary based on the type of individual’s response and the type of anti-diabetic drug. Common side effects include diarrhea, gastrointestinal disorders, edema, nausea, heart failure, severe hypoglycemia, weight gain, and vomiting (Ashaolu et al. 2024; Yuzbasioglu et al. 2022). Seaweeds have potential antidiabetic effects, and several studies have shown the positive impacts of seaweed on blood glucose control and the prevention of diabetes-related complications. Animals produce an enzyme called α-glucosidase, which regulates blood glucose levels and breaks down carbohydrates into sugars. α-Glucosidase inhibitors from the natural environment, including seaweed. Polyphenols from seaweed exhibit anti-inflammatory and antioxidant properties (Gómez-Guzmán et al. 2018; Michalak et al. 2022).
Brown seaweed is considered the major reserve of anti-inflammatory substances with various chemical compounds. These compounds are polysaccharides, polyphenols, halogenated compounds, carotenoids, and fatty acids (Fernando et al. 2016; Palanisamy et al. 2017). In brown algae, fucoidan is the major reserve of phytochemicals and contains approximately 20% to 60% fucose with varying α-glycosidic bonds. Fucoidan is considered the major phytochemical compound in brown algae (Jaswir and Monsur 2011). Brown algae contain phlorotannins, which are polyphenolic compounds that have anti-inflammatory effects. The available phlorotannins in seaweed inhibit the generation of reactive oxygen species in the cellular system and prevent cellular damage (Chouh et al. 2022). Most previous works on anti-diabetic and anti-inflammatory activity of brown seaweeds have been performed by extraction using different solvents rather than adequate phytochemical quantification and in vitro validation. In the present study, it was hypothesized that seaweed extracts alters physiological complications due to the presence of bioactive compounds. To evaluate the bioactive potential of brown algae, the present study was carried out to analyze the anti-inflammatory, antioxidant, and antidiabetic activities of seaweed.
EXPERIMENTAL
Seaweed Samples
Brown algae (Sargassum boveanum, Padina gymnospora, and Dictyota dichotoma) were collected from the Red Sea Coast of Jazan region, Saudi Arabia, and further washed with tap water to remove salt and epiphytes. The collected seaweeds were then lyophilized, blundered to make a fine powder and stored at −20 °C until use.
Proximate Composition of Seaweed
The moisture content of each sample was determined by heating it in a hot air oven (105 °C) for 12 h, and a constant weight was obtained. The ash content of the sample was determined via the gravimetric method by heating in a muffle furnace at 550 °C for 5 h (TAPPI 2007). The fat content of the seaweed was determined by AOAC 920.85 via petroleum ether solvent and Soxhlet extraction for 6 h (AOAC 2024). The total protein content of the seaweed extract was obtained using the Kjeldahl method, and the values were multiplied by 6.25 (Polat and Ozogul 2013). The carbohydrate content of each sample was calculated from the seaweed content. The lignin content of the seaweed was estimated following the method of Technical Association of the Pulp and Paper Industry(TAPPI) (TAPPI 2006). The contents of α-cellulose and hemicellulose were determined as described by Rowell (2005) and Wise et al. (1946).
Extraction
Seaweeds were subjected to solvent extraction, and the following solvent systems were used: ethanol, acetone, ethyl acetate, and chloroform. Five grams of seaweed powder was gently added to an amber flask with solvent (1:30 w/v), and the mixture was stirred at 125 rpm for 24 h at 50 °C. The extract was collected, 100 mL of fresh solvent was added, and this step was carried out three times. The collected extract was subsequently centrifuged, the residues were removed, and the final supernatant was dried and suspended in 5 mL of ethanol:water (75:25, v/v). To calculate the yield, 2 mL of seaweed extract was placed in a crucible and kept in an oven at 110 °C for 12 h. Then, it was placed in a desiccator, cooled, and weighed (Das et al. 2025). The extract yield was calculated following Eq. 1,
(1)
where denotes initial weight; is crucible weight; and denotes final weight after freeze-drying.
Determination of Total Phenolic Content
The total phenolic content (TPC) of the seaweed extracts were evaluated using a colorimetric test. Briefly, 0.025 mL of seaweed extract was mixed with 0.075 mL of double distilled water and 0.025 mL of 1 N Folin–Ciocalteu reagent and incubated in the dark for 10 min. Then, 0.1 mL of sodium carbonate (50 g/L) was added, and the mixture was incubated in the dark at ambient temperature. The absorbance of each sample was read at 765 nm, and the yield was expressed as gallic acid equivalents (GAE) per gram (Salar et al. 2012).
Determination of Flavonoid Contents
The amount of flavonoids in the extract was determined as suggested by Kim et al. (2006), with slight modifications. Briefly, 0.2 mL of crude extract was mixed with 1.0 mL of double distilled water and 0.05 mL of 5% NaNO2 solution. The mixture was incubated for 5 min, and 0.12 mL of 10% AlCl3 was added and incubated in the dark. Then, 0.4 mL of 1 M NaOH solution was added, and 0.25 mL of double distilled water was added to the blank and test samples. The absorbance values of the test, standard, and blank samples were read at 510 nm. Quercetin was prepared at various concentrations (0 to 1.0 mg/mL) and was used as a positive control.
Antioxidant Assay
DPPH Scavenging assay
The DPPH (2,2-diphenyl-1-picrylhydrazyl)-scavenging assay is based on the antioxidant activity of seaweed extracts. The DPPH activity was assayed spectrophotometrically at 517 nm using the stable nitrogen radical DPPH. In this method, 0.025 mL of seaweed extract was mixed with a newly prepared 0.2 mL of DPPH solution (50 mg/mL) and incubated for 20 min in the dark at ambient temperature. Trolox (6-hydroxy-2-5-7-8-tetramethylchroman-2-carboxylic acid) was used as a positive control. The final results were expressed as Trolox equivalents per gram of seaweed extract (TE/g) (Wu et al. 2003).
Ferric reducing antioxidant power assay
The ferric reducing antioxidant power (FRAP) analysis was carried out by mixing 0.025 mL of the extract with 0.175 mL of FRAP reagent. The FRAP reagent was prepared by mixing sodium acetate, 2,4,6-tripyridyl-s-triazine (TPTZ), and Fe3+ at a 10:1:1 ratio. FRAP analyses were carried out by adding 0.025 mL of seaweed extract to 0.175 mL of FRAP reagent. The mixture was mixed and incubated for 5 min at 37 °C for the end point of the reaction, and the absorbance of the sample was read at 593 nm (Wu et al. 2003). The FRAP data are presented as ascorbic acid equivalents per gram of dry weight (AAE/g). Ascorbic acid was used as the positive control.
ABTS antioxidant assay
The 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method for the antioxidant assay was performed as described previously by Arnao et al. (2001). Briefly, 2 mM ABTS and 70 mM potassium persulfate were mixed and kept under darkness overnight at ambient temperature to generate radical cations from ABTS. Then, the mixture was further diluted with methanol (80%), and the absorbance of the mixture was tested. Absorbance values <0.700 were used for analysis at 734 nm. Then, 0.05 mL of sample was mixed with 1.95 mL of ABTS solution and incubated for 6 min. The absorbance of the sample was read at 734 nm at ambient temperature, and Trolox (6-hydroxy-2-5-7-8-tetramethylchroman-2-carboxylic acid) was used as a positive control.
In vitro Anti-diabetic Activity of Seaweed Extract
a-Amylase inhibition assay
The a-amylase inhibition of the seaweed extract was tested as suggested by Daoudi et al. (2020), with slight modifications. Briefly, 0.2 mL of seaweed extract or acarbose (positive control) was mixed with 0.2 mL of phosphate buffer and 0.1 mL of enzyme (>25 IU). The tubes were preincubated for 10 min at 37 °C before the addition of 1% soluble starch prepared in phosphate buffer. Furthermore, this reaction was performed for 20 min at 37 °C. Then, 0.5 mL3,5-dinitrosalicylic acid (DNS) reagent was added, and the mixture was incubated for 5 min at 100 °C in a water bath. Finally, the absorbance of the sample was read at 540 nm, and the percentage inhibition (% inhibition) was calculated via the following Eq. 2:
(2)
a-Glucosidase inhibition assay
The a-glucosidase inhibitory effect of the seaweed extract was determined as suggested by Hbika et al. (2022). Briefly, the reaction mixture comprised 0.1 mL of 50 mM sucrose, 1.0 mL of phosphate buffer (50 mM, pH 7.5), and 0.1 mL of intestinal a-glucosidase enzyme (>10 IU). This mixture was mixed with 5 mL of double distilled water (negative control), seaweed extract, or acarbose (positive control). The mixture was incubated at 37 °C for 30 min in a water bath incubator. The amount of released glucose was measured, and the percentage inhibition was calculated.
Anti-inflammatory Activity
Human red blood cell membrane solubilization assay
The membrane solubilization assay using human red blood cell(HRBC) was performed as described earlier by Moualek et al. (2016). Briefly, heparinized blood was collected and centrifuged at 2000×g for 10 min at 4 °C. The collected HRBCs were subsequently suspended in isotonic phosphate-buffered saline (10 mM, pH 7.4). Salicylic acid was prepared at a 3.6 mM concentration and was used as the positive control, and DMSO (20%) was used as the negative control. The assay mixture consisted of HRBC (2%), mixed with 0.1 mL of extract and incubated for 10 min at 37 °C. The mixture was centrifuged at 2000 ×g for 5 min. The absorbance of the sample was read at 540 nm against a blank, and the percentage HRBC degradation was determined. The result was reported as a percentage (%) of inhibition. Diclofenac sodium was used as the standard anti-inflammatory drug.
Cyclooxygenase enzyme inhibition assay
A cyclooxygenaseenzyme (COX-2) inhibition assay was performed using the inhibitor screening assay kit based on the manufacturer’s instructions. Briefly, the seaweed extract was suspended in DMSO at a concentration of 0.5 g/mL before being subjected to this assay. The percentage inhibition was calculated (Cayman Chemical, MI, USA).
Statistical Analysis
The experimental results were expressed as mean ± standard deviation (SD). The results were tested using one-way analysis of variance (ANOVA) and the p < 0.05 was considered statistically significant.
RESULTS AND DISCUSSION
Proximate Composition of Seaweed
The proximate composition of the seaweed samples was determined, and the results are presented in Table 1. The moisture content of the seaweed varies from 4.8±0.2 to 9.5±0.5, which is within the range as reported previously (Hossain et al. 2021). The ash content was greater in the Padina gymnospora extract (15.3±0.37%) than that in the other seaweeds (p<0.05). The ash content of the seaweed ranged from 8% to 40% (Bhuiyan et al. 2016), which was within the limit of seaweed extract. In general, seaweed contains minerals and high concentrations of metals and minerals that improve the ash composition of seaweed (Samarasinghe et al. 2021). The moisture content of seaweed observed in this study ranges from 4.8±0.2 to 9.5±0.5, which is similar to that of green, red, and brown algae (Patel et al. 2020). The ash content of seaweed was high in P. gymnospora (15.3±0.37%), and it was higher than that reported previously for other seaweed species (Cebrián-Lloret et al. 2024). The ash content of seaweed was greater than that of green and red algae and varies on the basis of heavy metal uptake and the physicochemical parameters of seawater (Manns et al. 2014; Olsson et al. 2020). Fat and protein contents were high in S. boveanum (15.3±0.9% and 17.4±2.2%), whereas carbohydrate levels were greater in D. dichotoma (59.5±2.2%) (p<0.05). The total protein content was 0.57 wt% in P. gymnospora (Yang et al. 2022) and 3.2 ± 0.12 wt% in S. subrepandum (Abou-El-Wafa et al. 2011). Moreover, Agustín et al. (2023) reported 49.05 ± 1.36 wt% protein content. The variation in protein levels in seaweed varies with geographical location, species, reproduction, growth, and other environmental conditions.
Table 1. Proximate Composition of Three Different Seaweeds
Effects of Organic Solvents on Phytochemical Extraction
The data on the extraction potential of organic solvents in terms of extraction yield (%) are presented in Table 2. The ethanolic extracts presented greater yields than the other solvents did (acetone, ethyl acetate, and chloroform), and the values ranged from 5.1±0.9 to 25.2±1.3%, 2.2±0.4 to 35.3±1.1%, and 3.3±0.5 to 20.6±1.2%, for S. boveanum, P. gymnospora, and D. dichotoma, respectively (p<0.05). The recovery efficiency was high for ethanol because of its high polarity, which was associated with the nonselective extraction of several macroalgal phytochemical compounds, including polysaccharides and proteins. The present findings revealed that the recovery efficiency of plant components was dependent mainly on the chemical properties (polarity) of the organic solvent used. In addition, the yield of solvent extract has been found to be based on various factors, such as the extraction method, selected matrix, temperature, extraction time, and polarity of the solvent (Chan et al. 2014). Similarly, 50% ethanol has been considered to be the potent solvent for the extraction of phytochemicals from the Clitoria ternatea flowers (Jeyaraj et al. 2021).
Table 2. Effect of Organic Solvent on the Yield (%) of the Seaweed Extract
Total Flavonoid and Phenolic Contents of the Seaweeds
The total flavonoid and phenolic contents of the seaweed extracts were tested on the basis of milligram quercetin equivalents (mg QEs), as described in Table 3. The highest total flavonoid content was found in the ethyl acetate fraction of P. gymnospora, with a value of 91.5±1.2 mg QE/g. This was followed by the ethyl acetate fraction of S. boveanum, with a value of 84.3±3.1 mg QE/g. These findings revealed that ethyl acetate is an effective solvent for seaweed flavonoid extraction and the extraction capacity varied significantly (p<0.05).
The acetone extract and chloroform extract presented the lowest values. For S. boveanum, P. gymnospora, and D. dichotoma, the mean amount of polyphenols was determined. The total flavonoid content of the ethyl acetate extract of S. fusiforme, with a value of 13.42 mg QUE/g, was investigated by Lee et al. (2022). The phenolic content of the methanol extract of U. intestinalis was 12.59 ± 2.27 mg GAE/g dry weight, and it was 88.70 ± 2.19 mg GAE/g in the methanol extract of G. longissima (Ullah et al. 2024). Moreover, methanol has been reported to be an efficient solvent for the recovery of phytochemicals from natural sources (Chan et al. 2014; Ullah et al. 2023).
These findings are in line with those of a previous report on the presence of bioactive compounds from brown seaweed (Tanna et al. 2019). The polyphenolic content of the seaweed extract was established after methanolic extraction in G. bursapastoris (Yildiz et al. 2011). The contents of phenols and flavonoids detected in the ethyl acetate extract were greater than reported previously. In P. tetrastromatica, the methanolic extract contained 41.77 mg of QE/g of total flavonoids and 85.61 mg of GA/g of total phenolic content (Sobuj et al. 2021).
Table 3. Total Flavonoids and Polyphenols in the Solvent Extracts of Brown Seaweed
Antioxidant Activity of the Seaweed Extract
The antioxidant activity of the seaweed extract was determined via DPPH-radical scavenging, ABTS, and FRAPS assays, and the results are presented in Table 4. The antioxidant activity of plant phytochemicals is heterogeneous in nature; hence, analysis of antioxidant activity via different methods is suggested to explore the antioxidant mechanism of action.
The DPPH radical scavenging activity of S. boveanum ranged between 18.4±0.3 and 42.4±0.4 TE/g, whereas the ethyl acetate extract of P. gymnospora presented the maximum DPPH activity (65.3±1.1 TE/g). The ethanol extract of P. gymnospora had 27.6±0.5 AAE/g in the FRAP assay, whereas the ethyl acetate extract of P. gymnospora had 37.3±0.8 TE/g activity (p<0.05) (Table 4).
In this study, the increased amount of flavonoids and polyphenols presented maximum antioxidant activity due to the presence of high phytochemical content in the extract. The antioxidant activity of the solvent extracts of seaweed may be attributed to bioactive compounds such as phenols and tannins.
Dang et al. (2018) reported the ABTS radical scavenging activities of a solvent extract (0.06 mg/mL of Sargassum species such as S. podocanthum, S. linearifolium, and S. vestitum), and the activities were 13.30, 2.02, and 31.71 mg TE/g extract, respectively. Phytochemical compounds such as phenols and tannins significantly contribute to antioxidant activity, and these compounds may be present in solvent extracts (Phang et al. 2023). The antioxidant activity of seaweed confirmed that it can be used in the development of functional foods and antioxidant cosmetics.
Table 4. Antioxidant Activity of the Seaweed Extracted Using Four Different Solvents
Anti-Diabetic Activity of Seaweed Extract
The effects of seaweed extract on a-amylase and a-glucosidase inhibition are presented in Table 5. The results revealed that the seaweed extract inhibited a-amylase activity. Among the seaweeds, the ethyl acetate extract of P. gymnospora presented a low IC50 value (0.28±0.04 mg/mL). In addition, the present findings revealed that the seaweed extract significantly reduced a-glucosidase activity (p<0.05) (Table 5).
Table 5. Anti-diabetic Activities of the Seaweeds Extracted using Four different Solvents
Among the solvent extracts, the ethanolic extract of S. boveanum presented significant activity compared with the other solvents. Natural inhibitors, either a-amylase or a-glucosidase, are considered effective hyperglycemia-controlling agents rather than inorganic drugs (Daoudi et al. 2020). The phenolic compounds detected in the seaweed extract exhibited enzyme inhibitor activity. Gallic acid is considered a good enzyme inhibitor that inhibits amylases (Lordan et al. 2013). Phytochemical compounds can stimulate insulin production by increasing peripheral glucose uptake in animals (Abdel-Moneim et al. 2018). The percentage inhibition of carbohydrate degrading enzymes indicated that seaweed can be used as effective antidiabetic agents (Shafay et al. 2021).
Anti-inflammatory Activity of Seaweed Extracts
The seaweed extracts were tested for their HRBC protection and COX-2 inhibition activities. The maximum HRBC protection activity was observed with the S. boveanum ethyl acetate extract (43.7±1.2%), followed by the P. gymnospora ethyl acetate extract (40.3±0.6%), and they varied significantly among the seaweeds (p<0.05). In the COX-2 inhibition assay, the highest percentage of inhibition was observed with the acetone extract of S. boveanum (37.1±0.2%) in comparison to the other solvent extracts (p<0.05) (Table 6). In addition, the other extracts moderately inhibited COX-2. COX enzymes are involved in the synthesis of prostaglandins and are involved in the mediation of various inflammatory reactions, and inhibiting the synthesis of these prostaglandins alleviates the development of fever and pain (Gautier and Choukem 2008; Bases et al. 2025). In this study, the anti-inflammatory response varied based on the available phytochemicals in the extract. An anti-inflammatory mechanism has been established. During the inflammatory process, lysosomal enzymes are released. The enzyme activity of lysosomes is considered the major cause and is associated with chronic or acute inflammation.
Table 6. Anti-inflammatory Activity of Seaweed Extract
The functional properties of HRBC membranes are similar to those of lysosomal membranes, and this assay is used to indirectly determine the stability of lysosomal membranes (Wong and Cheung 2000). The Laminaria species exhibited anti-inflammatory activity and was evaluated in vitro. The extract of Laminaria japonica reduces the inflammatory response via nitrous oxide production and decreases reactive oxygen species generation (Lin et al. 2016).
CONCLUSIONS
- Seaweeds are rich in various phytochemical compounds, including polyphenols, polysaccharides, sterols, and pigments. These contribute antioxidant, anti-inflammatory, and antidiabetic activities.
- The availability of bioactive phytochemicals (flavonoids, terpenoids, and polyphenols)are significantly influenced by the type of solvent (methanol, ethanol, and acetone) used for extraction and the type of seaweed.
- Seaweeds can be utilized as natural sources of antioxidant, anti-inflammatory, and antidiabetic compounds for the preparation of functional feed or as dietary supplements.
ACKNOWLEDGMENTS
The authors extend their appreciation to the Ongoing Research Funding Program (ORF-2026-393), King Saud University, Riyadh, Saudi Arabia.
Conflict of Interest
Authors do not have any conflict of interest in publication of this research article.
Use of Generative AI
Authors did not use any AI tools in the preparation of text, data analysis, and collation of references.
REFERENCES CITED
Abdel-Moneim, A., Abd El-Twab, S. M., Yousef, A. I., Reheim, E. S. A., and Ashour, M. B. (2018). “Modulation of hyperglycemia and dyslipidemia in experimental type 2 diabetes by gallic acid and p-coumaric acid: The role of adipocytokines and PPARγ,” Biomedicine and Pharmacotherapy 105, 1091-1097. https://doi.org/10.1016/j.biopha.2018.06.096
Abou-El-Wafa, G. S., Shaaban, K. A., El-Naggar, M. E., and Shaaban, M. (2011). “Bioactive constituents and biochemical composition of the Egyptian brown alga Sargassum subrepandum (Forsk),” Revista Latinoamericana De Química 39(1-2), 62-74.
Agustín, R. V., Alberto, F. G. L., Ana, B., Isidoro, R. G. L., and Belén, D. A. (2023). “Rugulopteryx okamurae: Assessment of its potential as a source of monosaccharides for obtaining bio-products,” Chemical Engineering Journal 468, article 143578. https://doi.org/10.1016/j.cej.2023.143578
AOAC (2014). Fat (Crude) or eth Extract in Flour, Available online: http://www.aoacofficialmethod.org/index.php?main_page=product_info&products_id=244, accessed on 20, August 2024.
Ashaolu, T. J., Olatunji, O. J., Karaca, A. C., Lee, C. C., and Jafari, S. M. (2024). “Anti-obesity and anti-diabetic bioactive peptides: A comprehensive review of their sources, properties, and techno-functional challenges,” Food Research International 187, article 114427. https://doi.org/10.1016/j.foodres.2024.114427
Bases, E., El-Sheekh, M. M., El Shafay, S. M., El-Shenody, R., and Nassef, M. (2025). “Therapeutic anti-inflammatory immune potentials of some seaweeds extracts on chemically induced liver injury in mice,” Scientific Reports 15(1), article 4370. https://doi.org/10.1038/s41598-025-87379-9
Bhuiyan, K. A., Qureshi, S., Mustafa Kamal, A. H., AftabUddin, S., and Siddique, A. (2016). “Proximate chemical composition of sea grapes Caulerpa racemosa (J. Agardh, 1873) collected from a sub-tropical coast,” Virology and Mycology 5(158), 2161-0517. https://doi.org/10.4172/2161-0517.1000158
Cebrián-Lloret, V., Cartan-Moya, S., Martínez-Sanz, M., Gómez-Cortés, P., Calvo, M. V., López-Rubio, A., and Martínez-Abad, A. (2024). “Characterization of the invasive macroalgae Rugulopteryx okamurae for potential biomass valorization,” Food Chemistry 440, article 138241. https://doi.org/10.1016/j.foodchem.2023.138241
Chan, P. T., Matanjun, P., Yasir, S. M., and Tan, T. S. (2014). “Antioxidant and hypolipidaemic properties of red seaweed, Gracilaria changii,” Journal of Applied Phycology 26(2), 987-997. https://doi.org/10.1007/s10811-013-0135-z
Chan, P. T., Matanjun, P., Yasir, S. M., and Tan, T. S. (2015). “Antioxidant activities and polyphenolics of various solvent extracts of red seaweed, Gracilaria changii,” Journal of Applied Phycology 27(6), 2377-2386. https://doi.org/10.1007/s10811-014-0493-1
Chouh, A., Nouadri, T., Catarino, M. D., Silva, A. M., and Cardoso, S. M. (2022). “Phlorotannins of the brown algae Sargassum vulgare from the Mediterranean Sea coast,” Antioxidants 11(6), article 1055. https://doi.org/10.3390/antiox11061055
Dang, T. T., Bowyer, M. C., Van Altena, I. A., and Scarlett, C. J. (2018). “Comparison of chemical profile and antioxidant properties of the brown algae,” International Journal of Food Science and Technology 53(1), 174-181. https://doi.org/10.1111/ijfs.13571
Daoudi, N. E., Bouhrim, M., Ouassou, H., Legssyer, A., Mekhfi, H., Ziyyat, A., Aziz, M., and Bnouham, M. (2020). “Inhibitory effect of roasted/unroasted Argania spinosa seeds oil on α-glucosidase, α-amylase and intestinal glucose absorption activities,” South African Journal of Botany 135, 413-420. https://doi.org/10.1016/j.sajb.2020.09.020
Daoudi, N. E., Bouziane, O., Bouhrim, M., and Bnouham, M. (2022). “Natural aldose reductase inhibitors for treatment and prevention of diabetic cataract: A review,” Herba Polonica 68(1), 35-58. https://doi.org/10.2478/hepo-2022-0002
Das, R. S., Tiwari, B. K., Selli, S., Kelebek, H., and Garcia-Vaquero, M. (2025). “Exploring pilot scale ultrasound-microwave assisted extraction of organic acids and phytochemicals from brown seaweed Alaria esculenta,” Algal Research 86, article 103896. https://doi.org/10.1016/j.algal.2025.103896
Deshpande, A. D., Harris-Hayes, M., and Schootman, M. (2008). “Epidemiology of diabetes and diabetes-related complications,” Physical Therapy 88(11), 1254-1264. https://doi.org/10.2522/ptj.20080020
Ferdous, U. T., and Balia Yusof, Z. N. (2021). “Insight into potential anticancer activity of algal flavonoids: current status and challenges,” Molecules 26(22), article 6844. https://doi.org/10.3390/molecules26226844
Fernando, I. S., Nah, J. W., and Jeon, Y. J. (2016). “Potential anti-inflammatory natural products from marine algae,” Environmental Toxicology and Pharmacology 48, 22-30. https://doi.org/10.1016/j.etap.2016.09.023
Gautier, J. F., and Choukem, S. P. (2008). “Les incrétines,” Nutrition Clinique et Métabolisme 22(2), 59-65. https://doi.org/10.1016/j.nupar.2008.04.009
Gómez-Guzmán, M., Rodríguez-Nogales, A., Algieri, F., and Gálvez, J. (2018). “Potential role of seaweed polyphenols in cardiovascular-associated disorders,” Marine Drugs 16(8), article 250. https://doi.org/10.3390/md16080250
Hbika, A., Daoudi, N. E., Bouyanzer, A., Bouhrim, M., Mohti, H., Loukili, E. H., Mechchate, H., Al-Salahi, R., Nasr, F. A., Bnouham, M., and Zaid, A. (2022). “Artemisia absinthium L. aqueous and ethyl acetate extracts: antioxidant effect and potential activity in vitro and in vivo against pancreatic α-amylase and intestinal α-glucosidase,” Pharmaceutics 14(3), article 481. https://doi.org/10.3390/pharmaceutics14030481
Hossain, M. S., Sifat, S. A. D., Hossain, M. A., Salleh, S., Hossain, M., Akter, S., and Hossain, M. B. (2021). “Comparative assessment of bioactive compounds, antioxidant capacity and nutritional quality of red seaweeds and water spinach,” Regional Studies in Marine Science 46, article 101878. https://doi.org/10.1016/j.rsma.2021.101878
Janarthanan, M., and Senthil Kumar, M. (2018). “The properties of bioactive substances obtained from seaweeds and their applications in textile industries,” Journal of Industrial Textiles 48(1), 361-401. https://doi.org/10.1177/1528083717692596
Jaswir, I., and Monsur, H. A. (2011). “Anti-inflammatory compounds of macro algae origin: A review,’ Journal of Medicinal Plants Research 5(33), 7146-7154. https://doi.org/10.5897/JMPR11.018
Jeyaraj, E. J., Lim, Y. Y., and Choo, W. S. (2021). “Effect of organic solvents and water extraction on the phytochemical profile and antioxidant activity of Clitoria ternatea flowers,” ACS Food Science & Technology 1(9), 1567-1577. https://doi.org/10.1021/acsfoodscitech.1c00168
Kim, J. H., Park, S. M., Ha, H. J., Moon, C. J., Shin, T. K., Kim, J. M., Lee, N. H., Kim, H. C., Jang, K. J., and Wie, M. B. (2006). “Opuntia ficus-indica attenuates neuronal injury in in vitro and in vivo models of cerebral ischemia,” Journal of Ethnopharmacology 104(1-2), 257-262. https://doi.org/10.1016/j.jep.2005.09.017
Lee, H. H., Kim, J. S., Jeong, J. H., Lee, S. Y., and Kim, C. S. (2022). “Comparative analysis of biological activities and phenolic content between fresh and steamed Sargassum fusiforme in different extraction solvents,” Applied Sciences 12(23), article 12161. https://doi.org/10.3390/app122312161
Lin, H. T. V., Lu, W. J., Tsai, G. J., Chou, C. T., Hsiao, H. I., and Hwang, P. A. (2016). “Enhanced anti-inflammatory activity of brown seaweed Laminaria japonica by fermentation using Bacillus subtilis,” Process Biochemistry 51(12), 1945-1953. https://doi.org/10.1016/j.procbio.2016.08.024
Lobo, V., Patil, A., Phatak, A., and Chandra, N. (2010). “Free radicals, antioxidants and functional foods: Impact on human health,” Pharmacognosy Reviews 4(8), article 118. https://doi.org/10.4103/0973-7847.70902
Lomartire, S., and Gonçalves, A. M. (2022). “An overview of potential seaweed-derived bioactive compounds for pharmaceutical applications,” Marine Drugs 20(2), article 141. https://doi.org/10.3390/md20020141
Lordan, S., Smyth, T. J., Soler-Vila, A., Stanton, C., and Ross, R. P. (2013). “The α-amylase and α-glucosidase inhibitory effects of Irish seaweed extracts,” Food Chemistry 141(3), 2170-2176. https://doi.org/10.1016/j.foodchem.2013.04.123
Mac Monagail, M., Cornish, L., Morrison, L., Araújo, R., and Critchley, A. T. (2017). “Sustainable harvesting of wild seaweed resources,” European Journal of Phycology 52(4), 371-390. https://doi.org/10.1080/09670262.2017.1365273
Manns, D., Deutschle, A. L., Saake, B., and Meyer, A. S. (2014). “Methodology for quantitative determination of the carbohydrate composition of brown seaweeds (Laminariaceae),” RSC Advances 4(49), 25736-25746. https://doi.org/10.1039/C4RA03537B
Mendes, G. D. S., Soares, A. R., Martins, F. O., Albuquerque, M. C. M. D., Costa, S. S., Yoneshigue-Valentin, Y., Gestinari, L. M. D. S., Santos, N., and Romanos, M. T. V. (2010). “Antiviral activity of the green marine alga Ulva fasciata on the replication of human metapneumovirus,” Revista do Instituto de Medicina Tropical de São Paulo 52, 03-10. https://doi.org/10.1590/S0036-46652010000100001
Michalak, I., Tiwari, R., Dhawan, M., Alagawany, M., Farag, M. R., Sharun, K., Emran, T. B., and Dhama, K. (2022). “Antioxidant effects of seaweeds and their active compounds on animal health and production– A review,” Veterinary Quarterly 42(1), 48-67. https://doi.org/10.1080/01652176.2022.2061744
Morais, T., Inácio, A., Coutinho, T., Ministro, M., Cotas, J., Pereira, L., and Bahcevandziev, K. (2020). “Seaweed potential in the animal feed: A review,” Journal of Marine Science and Engineering 8(8), article ID 559. https://doi.org/10.3390/jmse8080559
Moualek, I., Aiche, G. I., Guechaoui, N. M., Lahcene, S., and Houali, K. (2016). “Antioxidant and anti-inflammatory activities of Arbutus unedo aqueous extract,” Asian Pacific Journal of Tropical Biomedicine 6(11), 937-944. https://doi.org/10.1016/j.apjtb.2016.09.002
Mutalipassi, M., Esposito, R., Ruocco, N., Viel, T., Costantini, M., and Zupo, V. (2021). “Bioactive compounds of nutraceutical value from fishery and aquaculture discards,” Foods 10(7), article 1495. https://doi.org/10.3390/foods10071495
Olsson, J., Toth, G. B., and Albers, E. (2020). “Biochemical composition of red, green and brown seaweeds on the Swedish west coast,” Journal of Applied Phycology 32(5), 3305-3317. https://doi.org/10.1007/s10811-020-02145-w
Palanisamy, S., Vinosha, M., Marudhupandi, T., Rajasekar, P., and Prabhu, N. M. (2017). “Isolation of fucoidan from Sargassum polycystum brown algae: Structural characterization, in vitro antioxidant and anticancer activity,” International Journal of Biological Macromolecules 102, 405-412. https://doi.org/10.1016/j.ijbiomac.2017.03.182
Patel, M. R., Ojha, M. L., Vadher, K. H., Saini, V. P., Sharma, B. K., Sharma, S. K., and Ishakani, A. H. (2020). “Biochemical composition of seaweeds from Veraval coastal regions along Saurashtra coast of Gujarat, India,” International Journal of Chemical Studies 8, 1508-1511. https://doi.org/10.22271/chemi.2020.v8.i1u.8469
Pérez-Lloréns, J. L., Mouritsen, O. G., Rhatigan, P., Cornish, M. L., and Critchley, A. T. (2020). “Seaweeds in mythology, folklore, poetry, and life,” Journal of Applied Phycology 32(5), 3157-3182. https://doi.org/10.1007/s10811-020-02133-0
Phang, S. J., Teh, H. X., Looi, M. L., Arumugam, B., Fauzi, M. B., and Kuppusamy, U. R. (2023). “Phlorotannins from brown algae: A review on their antioxidant mechanisms and applications in oxidative stress-mediated diseases,” Journal of Applied Phycology 35(2), 867-892. https://doi.org/10.1007/s10811-023-02913-4
Polat, S., and Ozogul, Y. (2013). “Seasonal proximate and fatty acid variations of some seaweeds from the northeastern Mediterranean coast,” Oceanologia 55(2), 375-391. https://doi.org/10.5697/oc.55-2.375
Raja, K., Kadirvel, V., and Subramaniyan, T. (2022). “Seaweeds, an aquatic plant-based protein for sustainable nutrition – A review,” Future Foods 5, article 100142. https://doi.org/10.1016/j.fufo.2022.100142
Rowell, R. M. (2005). Handbook of Wood Chemistry and Wood Composites, CRC Press. https://doi.org/10.1201/9780203492437
Safafar, H., Van Wagenen, J., Møller, P., and Jacobsen, C. (2015). “Carotenoids, phenolic compounds and tocopherols contribute to the antioxidative properties of some microalgae species grown on industrial wastewater,” Marine Drugs 13(12), 7339-7356. https://doi.org/10.3390/md13127069
Samarasinghe, M. B., Van Der Heide, M. E., Weisbjerg, M. R., Sehested, J., Sloth, J. J., Bruhn, A., Vestergaard, M., Nørgaard, J. V., and Hernández-Castellano, L. E. (2021). “A descriptive chemical analysis of seaweeds, Ulva sp., Saccharina latissima and Ascophyllum nodosum harvested from Danish and Icelandic waters,” Animal Feed Science and Technology 278, article 115005. https://doi.org/10.1016/j.anifeedsci.2021.115005
Schmid, M., Kraft, L. G., van der Loos, L. M., Kraft, G. T., Virtue, P., Nichols, P. D., and Hurd, C. L. (2018). “Southern Australian seaweeds: A promising resource for omega-3 fatty acids,’ Food Chemistry 265, 70-77. https://doi.org/10.1016/j.foodchem.2018.05.060
Shafay, S. E., El-Sheekh, M., Bases, E., and El-Shenody, R. (2021). “Antioxidant, antidiabetic, anti-inflammatory and anticancer potential of some seaweed extracts,” Food Science and Technology 42, article e20521. https://doi.org/10.1590/fst.20521
Sobuj, M. K. A., Islam, M. A., Islam, M. S., Islam, M. M., Mahmud, Y., and Rafiquzzaman, S. M. (2021). “Effect of solvents on bioactive compounds and antioxidant activity of Padina tetrastromatica and Gracilaria tenuistipitata seaweeds collected from Bangladesh,” Scientific Reports 11(1), article 19082. https://doi.org/10.1038/s41598-021-98461-3
Tanna, B., Brahmbhatt, H. R., and Mishra, A. (2019). “Phenolic, flavonoid, and amino acid compositions reveal that selected tropical seaweeds have the potential to be functional food ingredients,” Journal of Food Processing and Preservation 43(12), article e14266. https://doi.org/10.1111/jfpp.14266
TAPPI. (2006).“Acid insoluble lignin in wood and pulp,” Available online: https://www.tappi.org/content/sarg/t222.pdf, accessed on 20 August 2024.
TAPPI. (2007). “Ash in wood, pulp, paper and paperboard: combustion at 525 °C,” Available online: https://www.tappi.org/content/sarg/t211.pdf, accessed on 20 August 2024.
Ullah, M. R., Akhter, M., Khan, A. B. S., Yasmin, F., Hasan, M. M., Bosu, A., Haque, M. A., Islam, M. M., Islam, M. A., and Mahmud, Y. (2023). “Comparative estimation of nutritionally important chemical constituents of red seaweed, Gracilariopsis longissima, affected by different drying methods,” Journal of Food Quality 2023(1), article 6623247. https://doi.org/10.1155/2023/6623247
Ullah, M. R., Akhter, M., Khan, A. B. S., Yasmin, F., Hasan, M. M., Bosu, A., Haque, M. A., Islam, M. S., Islam, M. A., and Mahmud, Y. (2024). “Nutritional composition and phenolic contents of Gracilariopsis longissima, Padina tetrastromatica and Ulva intestinalis from the Bay of Bengal, Bangladesh coast,” Heliyon 10(10),article e31128. https://doi.org/10.1016/j.heliyon.2024.e24798
Wise, L. E., Murphy, M., and d’Addieco, A. A. (1946). “Chlorite holocellulose, its fractionation and bearing on summative wood analysis and on studies on the hemicelluloses,” Paper Trade Journal 122(2), 35-43.
Wong, K. H., and Cheung, P. C. (2000). “Nutritional evaluation of some subtropical red and green seaweeds: Part I—proximate composition, amino acid profiles and some physico-chemical properties,” Food Chemistry 71(4), 475-482. https://doi.org/10.1016/S0308-8146(00)00175-8
Wu, H. C., Chen, H. M., and Shiau, C. Y. (2003).“Free amino acids and peptides as related to antioxidant properties in protein hydrolysates of mackerel (Scomber austriasicus),” Food Res. Int. 36, 949-957. https://doi.org/10.1007/s41208-022-00436-2
Yang, Y., Qi, Y., Alalawy, A. I., Mohammed, G. M., Almasoudi, F. M., and Salama, E. S. (2022). “Potential of marine seaweeds for bioactive compounds: A comprehensive analysis of Padina australis biomass,” Thalassas: An International Journal of Marine Sciences 38(2), 947-956. https://doi.org/10.1007/s41208-022-00436-2
Yildiz, G., Vatan, Ö., Çelikler, S., and Dere, Ş. (2011). “Determination of the phenolic compounds and antioxidative capacity in red algae Gracilaria bursapastoris,” International Journal of Food Properties 14(3), 496-502. https://doi.org/10.1080/10942910903256949
Yuzbasioglu, D., Mahmoud, J. H., Mamur, S., and Unal, F. (2022). “Cytogenetic effects of antidiabetic drug metformin,” Drug and Chemical Toxicology 45(2), 955-962. https://doi.org/10.1080/01480545.2020.1844226
Article submitted: January 8, 2026;Peer review completed: February 7, 2026; Revised version received: March 31, 2026; Accepted: April 9, 2026; Published: April 22, 2026.
DOI: 10.15376/biores.21.2.5041-5056