Antioxidant and anti-cholinesterase activity of Sargassum wightii

BChE inhibitors from marine organisms - A review

Acetylcholine is a key neurotransmitter for brain and muscle function, that has its levels decreased in the brain of people with Alzheimer's Disease (AD). Cholinesterase inhibitors are medicines that decrease the breakdown of acetylcholine, through the inhibition of acetyl- and butyrylcholinesterase enzymes. Despite the fact that butyrylcholinesterase activity rises with the disease, while acetylcholinesterase activity declines, the cholinesterase inhibitors that are currently commercialized inhibit either acetylcholinesterase or both enzymes. The development of selective butyrylcholinesterase inhibitors is a promising strategy in the search for new drugs acting against AD. The marine environment is a rich source of molecules with therapeutic potential, which can provide compounds more easily than traditional methods, with reduced toxicity risks compared to synthetic molecules. This review comprises articles from 2003 to 2020, that assessed the butyrylcholinesterase inhibitory activities from marine organisms, considering their crude extracts and isolated compounds. Part of the articles reported a multi-target activity, inhibiting also other AD-related enzymes. Some of the marine compounds reported here have shown an excellent potential for butyrylcholinesterase inhibition compared to standard inhibitors. Further studies of some compounds reported here may lead to the development of a new treatment for AD.

Recent advances in biological properties of brown algae-derived compounds for nutraceutical applications

The increasing demand for nutraceuticals in the circular economy era has driven the research toward studying bioactive compounds from renewable underexploited resources. In this regard, the exploration of brown algae has shown significant growth and maintains a great promise for the future. One possible explanation could be that brown algae are rich sources of nutritional compounds (polyunsaturated fatty acids, fiber, proteins, minerals, and vitamins) and unique metabolic compounds (phlorotannins, fucoxanthin, fucoidan) with promising biological activities that make them good candidates for nutraceutical applications with increased value-added. In this review, a deep description of bioactive compounds from brown algae is presented. In addition, recent advances in biological activities ascribed to these compounds through in vitro and in vivo assays are pointed out. Delivery strategies to overcome some drawbacks related to the direct application of algae-derived compounds (low solubility, thermal instability, bioavailability, unpleasant organoleptic properties) are also reviewed. Finally, current commercial and legal statuses of ingredients from brown algae are presented, considering future therapeutical and market perspectives as nutraceuticals.

Spectral analysis and Antibacterial activity of the bioactive principles of Sargassum tenerrimum J. Agardh collected from the Red sea, Jazan, Kingdom of Saudi Arabia

Seaweeds are a major marine resource that can be explored to develop novel pharmaceutical molecules. The present study showed the presence of unique bioactive components in the petroleum ether extract (PEE) and methanolic extract (ME) of Sargassum tenerrimum. The gas chromatography-mass spectrometry analysis suggested that the PEE of S. tenerrimum contained antibacterial biomolecules: hexadecanoic acid, methyl ester, 17-pentatriacontene, dasycarpidan-1-methanol, and acetate (ester). However, the ME of S. tenerrimum exhibited better antibacterial effect than the PEE due to the presence of the bioactive compounds 1,2-benzenedicarboxylic acid, diisooctyl ester, tetratetracontane, 1-docosene, 1,2-benzenediol, and benzoic acid. Thus, promising antibacterial molecules can be isolated from S. tenerrimum for better therapeutic use.

Screening of In-Vitro Anti-Inflammatory and Antioxidant Activity of Sargassum ilicifolium Crude Lipid Extracts from Different Coastal Areas in Indonesia

Sargassum brown seaweed is reported to exhibit several biological activities which promote human health, such as anticancer, antimicrobial, antidiabetic, anti-inflammatory, and antioxidant activity. This study aimed to investigate the anti-inflammatory and antioxidant activity of crude lipid extracts of Sargassum ilicifolium obtained from four different coastal areas in Indonesia, namely Awur Bay-Jepara (AB), Pari Island-Seribu Islands (PI), Sayang Heulang Beach-Garut (SHB), and Ujung Genteng Beach-Sukabumi (UGB). Results showed that treatment of RAW 264.7 macrophage cells with UGB and AB crude lipid extracts (12.5-50 µg/mL) significantly suppressed the nitric oxide production after lipopolysaccharide stimulation, both in pre-incubated and co-incubated cell culture model. The anti-inflammatory effect was most marked in the pre-incubated cell culture model. Both two crude lipid extracts showed 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and high ferric reducing antioxidant power, which were amounted to 36.93-37.87 µmol Trolox equivalent/g lipid extract and 681.58-969.81 µmol FeSO4/g lipid extract, respectively. From this study, we can conclude that crude lipid extract of tropical S. ilicifolium can be further developed as a source of anti-inflammatory and antioxidant agent.

Contribution of Attenuation of TNF-α and NF-κB in the Anti-Epileptic, Anti-Apoptotic and Neuroprotective Potential of Rosa webbiana Fruit and Its Chitosan Encapsulation

Rosa webbiana L. (Rosaceae) is one of the least reported and most understudied members of this family. It is native to the Himalayan regions of Pakistan and Nepal. The anti-convulsant effect of n-hexane extract of fruit of Rosa webbiana was investigated in a pentylenetetrazole (PTZ)-induced animal model of epilepsy. Male Sprague-Dawley rats were divided into six groups (n = 7) including control, PTZ (40 mg/kg), diazepam (4 mg/kg) and n-hexane extract (at 50, 150 and 300 mg/kg). Convulsive behavior was observed and resultant seizures were scored, animals sacrificed and their brains preserved. Chitosan nanoparticles were prepared using the ionic gelation method and characterized by UV-analysis, zeta potential and Fourier transform infrared spectroscopy (FTIR). The effects of all the treatments on the expression of phosphorylated cytokine tumor necrosis factor α (p-TNF-α) and phosphorylated transcription factor nuclear factor kappa B (p-NF-κB) expression in the cortex and hippocampus of the brains of treated rats were studied through enzyme linked immunosorbent assay (ELISA) and morphological differences and surviving neuronal number were recorded through hematoxylene and eosin (H&E) staining. Significant changes in seizures score and survival rate of rats were observed. Downregulation of neuro-inflammation, p-TNF-α and p-NF-κB was evident. Gas Chromatography-Mass Spectrometry (GC-MS) analysis of this fraction showed multiple constituents of interest, including esters, alkanes and amines.

The Seaweed Diet in Prevention and Treatment of the Neurodegenerative Diseases

Edible marine algae are rich in bioactive compounds and are, therefore, a source of bioavailable proteins, long chain polysaccharides that behave as low-calorie soluble fibers, metabolically necessary minerals, vitamins, polyunsaturated fatty acids, and antioxidants. Marine algae were used primarily as gelling agents and thickeners (phycocolloids) in food and pharmaceutical industries in the last century, but recent research has revealed their potential as a source of useful compounds for the pharmaceutical, medical, and cosmetic industries. The green, red, and brown algae have been shown to have useful therapeutic properties in the prevention and treatment of neurodegenerative diseases: Parkinson, Alzheimer’s, and Multiple Sclerosis, and other chronic diseases. In this review are listed and described the main components of a suitable diet for patients with these diseases. In addition, compounds derived from macroalgae and their neurophysiological activities are described.

Enhancing and Complementary Mechanisms of Synergistic Action of Acori Tatarinowii Rhizoma and Codonopsis Radix for Alzheimer's Disease Based on Systems Pharmacology

Materials and Methods

In this study, a systems pharmacology-based strategy was used to elucidate the synergistic mechanism of Acori Tatarinowii Rhizoma and Codonopsis Radix for the treatment of AD. This novel systems pharmacology model consisted of component information, pharmacokinetic analysis, and pharmacological data. Additionally, the related pathways were compressed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and the organ distributions were determined in the BioGPS bank.

Results

Sixty-eight active ingredients with suitable pharmacokinetic profiles and biological activities were selected through ADME screening in silico. Based on 62 AD-related targets, such as APP, CHRM1, and PTGS1, systematic analysis showed that these two herbs were mainly involved in the PI3K-Akt signaling pathway, MAPK signaling pathway, neuroactive ligand-receptor interaction, and fluid shear stress and atherosclerosis, indicating that they had a synergistic effect on AD. However, ATR acted on the KDR gene, while CR acted on IGF1R, MET, IL1B, and CHUK, showing that they also had complementary effects on AD. The ingredient contribution score involved 29 ingredients contributing 90.14% of the total contribution score of this formula for AD treatment, which emphasized that the effective therapeutic effects of these herbs for AD were derived from both ATR and CR, not a single herb. Organ distribution showed that the targets of the active ingredients were mainly located in the whole blood, the brain, and the muscle, which are associated with AD.

Conclusions

In sum, our findings suggest that the systems pharmacology methods successfully revealed the synergistic and complementary mechanisms of ATR and CR for the treatment of AD.

Environmental contaminant 2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide remediation via Xanthomonas axonopodis and Aspergillus niger

Alachlor, a chloroacetanilide endocrine disruptor herbicide is precarious for humans as well as the environment. Though banned by the European Union and classified as moderately hazardous by WHO, yet it is nevertheless used in several countries posing austere human and environmental health issues. Alachlor attenuation was scrutinized through simulated biodegradation experiments using soil-isolated microbes. Bio-disintegrative assays of pure three fungal and one bacterial strain; Aspergillus flavus (AF), Penicillium chrysogenum (PC), Aspergillus niger (AN) and Xanthomonas axonopodis (XA), respectively were utilized. Initial Alachlor concentration (10 mg/L) was prepared with individual microbial suspension and monitored for 35 d. Alachlor bio-transformation was analyzed quantitatively and qualitatively by gas chromatography mass spectroscopy. XA and AN displayed maximal potential to metabolise the herbicide while forming residues; 1-chloroacetyl, 2,3- dihydro-7 ethylindole, 7 ethylindole, 7-ethyl-3-methyl-2-methoxy-2,3-dihydroindole, N- (2,6-diethylphenyl)-methyleneamine and 7-Ethyl-N-methylindole. Alachlor degradation by AF, PC, AN and XA was found to be 17.1%, 5.5%, 72.6% and 82.1%, respectively, after 35 d. Microbes have displayed cometabolism as the main mechanism for Alachlor degradation. This research can influence imperative and significant environmental friendly bio-remedial strategies for xenobiotic eradication.

The antioxidative effects of bioactive products from Sargassum polycystum C. Agardh and Sargassum duplicatum J. Agardh against inflammation and other pathological issues

The present study was aimed to determine the phenol, total flavonoids and antioxidant potentials of Sargassum polycystum C. Agardh and Sargassum duplicatum J. Agardh from south east coast of Tamil Nadu and India using DPPH, phophomolybdenum and hydrogen peroxide scavenging activity. The total phenols, total flavonoids and antioxidant activities of S. polycystum and S. duplicatum were determined. Highest phenols (33.49 and 149.52 mg GAE/g) were observed in chloroform extracts of S. polycystum and methanolic extracts of S. duplicatum. The acetone extracts of S. polycystumand S. duplicatum demonstrated maximum amount of flavonoids compared to other studied extracts. Maximum amount of phosphomolybdenum reduction was observed in acetone extracts of S. polycystum and methanolic extracts of S. duplicatum. The DPPH radical scavenging activity of different extracts of S. polycystum and S. duplicatum were as follows acetone > chloroform > Petroleum ether > methanol and acetone > chloroform > methanol >Petroleum ether respectively. The H2O2 scavenging activity of S. polycystum extracts were as follows Petroleum ether extracts of S. polycystum (67.9%) > acetone (67.3%) > chloroform (58.6%) > methanol (51.78%). Acetone extracts of S. duplicatum showed maximum inhibition (90.39%) followed by petroleum ether, chloroform and methanolic extracts (75.11, 72.37 and 54.59%) respectively. The present study results confirmed the antioxidant properties of the two selected brown seaweeds viz., S. polycytum and S. duplicatum. The total phenols, flavonoids and alkaloids may be responsible for the antioxidant activities.

Fucosterol exerts protection against amyloid β-induced neurotoxicity, reduces intracellular levels of amyloid β and enhances the mRNA expression of neuroglobin in amyloid β-induced SH-SY5Y cells

Alzheimer's disease (AD) is a neurodegenerative disease that leads to progressive loss of neurons which often results in deterioration of memory and cognitive function. The development of AD is highly associated with the formation of senile plaques and neurofibrillary tangles. Amyloid β (Aβ) induces neurotoxicity and contributes to the development of AD. Recent evidences also highlighted the importance of neuroglobin (Ngb) in ameliorating AD. This study assessed the ability of fucosterol, a phytosterol found in brown alga, in protecting SH-SY5Y cells against Aβ-induced neurotoxicity. Its effects on the mRNA levels of APP and Ngb as well as the intracellular Aβ levels were also determined in Aβ-induced SH-SY5Y cells. SH-SY5Y cells were exposed to fucosterol prior to Aβ treatment. The effect on apoptosis was determined using Annexin V FITC staining and mRNA expression was studied using RT-PCR. Flow cytometry confirmed the protective effects of fucosterol on SH-SY5Y cells against Aβ-induced apoptosis. Pretreatment with fucosterol increased the Ngb mRNA levels but reduced the levels of APP mRNA and intracellular Aβ in Aβ-induced SH-SY5Y cells. These observations demonstrated the protective properties of fucosterol against Aβ-induced neurotoxicity in neuronal cells.

Secondary Metabolites and Biological Activity of Invasive Macroalgae of Southern Europe

In this review a brief description of the invasive phenomena associated with algae and its consequences on the ecosystem are presented. Three examples of invasive algae of Southern Europe, belonging to Rodophyta, Chlorophyta, and Phaeophyta, were selected, and a brief description of each genus is presented. A full description of their secondary metabolites and biological activity is given and a summary of the biological activity of extracts is also included. In Asparagopsis we encounter mainly halogenated compounds. From Caulerpa, several terpenoids and alkaloids were isolated, while in Sargassum, meroterpenoids prevail.

Effective compounds in the fruit of Muntingia calabura Linn. cultivated in Taiwan evaluated with scavenging free radicals and suppressing LDL oxidation

The effective antioxidant compounds ofM. calaburaLinn. fruit.

Alpha-amylase inhibitory activity and sterol composition of the marine algae, Sargassum glaucescens

BACKGROUND

Sargassum species (phaeophyceae) are economically important brown algae in southern parts of Iran. Sargassum is mainly harvested as a row material in alginate production industries and is a source of plant foods or plant bio-stimulants even a component of animal foods.

OBJECTIVE

In this study, Sargassum glaucescens, collected from the seashore of Chabahar, was employed for phytochemical and biological evaluations.

MATERIALS AND METHODS

For that purpose, the dried algae was extracted by methanol and subjected to different chromatographic separation methods.

RESULTS

Six sterols, fucosterol (1), 24(S)-hydroxy-24-vinylcholesterol (2), 24(R)-hydroxy-24-vinylcholesterol (3), stigmasterol (4), β-sitosterol (5) and cholesterol (6) were identified by spectroscopic methods including (1)H-NMR, (13)C-NMR and mass spectroscopy. In vitro alpha-amylase inhibitory test was performed on the methanolic extract and the results revealed a potent inhibition (IC50 = 8.9 ± 2.4 mg/mL) of the enzyme compared to acarbose as a positive control.

CONCLUSION

Various biological activities and distribution of sterols in Sargassum genus have been critically reviewed here. The results concluded that these algae are a good candidate for further anti-diabetic investigations in animals and human.

Antilithiatic Activity of phlorotannin rich extract of Sarghassum Wightii on Calcium Oxalate Urolithiais - InVitro and In Vivo Evaluation

PURPOSE

Urolithiasis is a common urological disorder responsible for serious human affliction and cost to the society with a high recurrence rate. The aim of the present study was to systematically evaluate the phlorotannin rich extract of Sargassum wightii using suitable in vitro and in vivo models to provide scientific evidence for its antilithiatic activity.

MATERIALS AND METHODS

To explore the effect of Sargassum wightii on calcium oxalate crystallization, in vitro assays like crystal nucleation, aggregation and crystal growth were performed. Calcium oxalate urolithiasis was induced in male Sprague dawley rats using a combination of gentamicin and calculi producing diet (5% ammonium oxalate and rat pellet feed). The biochemical parameters like calcium, oxalate, magnesium, phosphate, sodium and potassium were evaluated in urine, serum and kidney homogenates. Histopathological studies were also done to confirm the biochemical findings.

RESULTS

The yield of Sargassum wightii extract was found to be 74.5 gm/kg and confirmed by quantitative analysis. In vitro experiments with Sargassum wightii showed concentration dependent inhibition of calcium oxalate nucleation, aggregation and growth supported by SEM analysis. In the in vivo model, Sargassum wightii reduced both calcium and oxalate supersaturation in urine, serum and deposition in the kidney. The biochemical results were supported by histopathological studies.

CONCLUSION

The findings of the present study suggest that Sargassum wightii has the ability to prevent nucleation, aggregation and growth of calcium oxalate crystals. Sargassum wightii has better preventive effect on calcium oxalate stone formation indicating its strong potential to develop as a therapeutic option to prevent recurrence of urolithiasis.

Assessment of mutagenic effect of G. acerosa and S. wightii in S. typhimurium (TA 98, TA 100, and TA 1538 strains) and evaluation of their cytotoxic and genotoxic effect in human mononuclear cells: a non-clinical study

The marine red algae (Gelidiella acerosa and Sargassum wightii) possessing excellent antioxidant and anticholinesterase activity were subjected to toxicity evaluation for a deeper understanding of other bioprotective properties of seaweeds. Cytotoxic evaluation was done by trypan blue exclusion, and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays using human PBMC (peripheral blood mononuclear cells) and RBC (red blood cells) lysis assay using human erythrocytes. Mutagenicity of the seaweeds was analyzed by Ames salmonella mutagenicity test with the histidine dependent mutant strains TA 98, TA100 and TA 1538. Genotoxic activity was verified in PBMC by comet assay. The results suggest that benzene extract of G. acerosa (BEGA) and dichloromethane extract of S. wightii (DMESW) did not show cytotoxic effect both in PBMC and erythrocytes. Evaluation of mutagenic activity suggests that the seaweeds did not cause any mutagenic effects both in the absence and the presence of S9 microsomal fraction in all the three Salmonella mutant strains. Results of genotoxic study showed that PBMC treated with seaweed extracts (1 mg/mL) exhibit less or no damage to cells, thus proving the non-genotoxic effect of the extract. Since these in vitro non-clinical studies clearly demonstrate the non-toxic nature of the seaweeds, they could be exploited for further characterization, which would result in development of novel and safe therapeutic entities.