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Context Gelidiella acerosa (Forsskål) Feldmann & G. Hamel (Rhodophyta-Gelidiales) is a marine red macroalga. Our previous work found that a benzene extract of G. acerosa possesses noticeable neuroprotective activity, when evaluated through in vitro and in vivo systems. Objective Bioactive-guided fractionation and identification of active compounds by column chromatography using solvents of varying polarity. Materials and methods Fractionation was done by column chromatography, antioxidant and anticholinesterase activity was assessed by DPPH and cholinesterase inhibition assays (50-200 μg/ml), compound identification was done by LC-MS analysis, the mode of interaction of active compound was analyzed through docking studies and quantification was done by high-performance thin-layer chromatography (HPTLC) analysis. Results The results suggest that fractions F9-F13 exhibited significant (p < 0.05) antioxidant and anticholinesterase activities. Hence, these fractions were pooled together and verified for neuroprotective activity. The pooled fraction was subjected to LC-MS analysis and among all the compounds, phytol was previously reported to possess excellent neuroprotective potential. Hence, the neuroprotective potential of phytol was assessed. The results suggest that phytol showed significant (p < 0.05) antioxidant activities (25-125 μg/ml) with an IC50 value of 95.27 ± 1.65 μg/ml and cholinesterase inhibitory potential (5-25 μg/ml) with IC50 values of 2.704 ± 0.07 and 5.798 ± 0.72 μg/ml for AChE and BuChE, respectively. Molecular docking studies suggest that phytol interacts with cholinesterase through the arginine residue of the enzyme. HPTLC quantification showed that about 6.266 μg of phytol was present per mg of pooled fraction. Conclusion The study suggests that phytol might act as the key compound in contributing to the neuroprotective potential of G. acerosa.

Context: Naturally occurring polyphenols including olive oil (OO) and its constituents hydroxytyrosol (HT) and tyrosol (TY), consumed in the Mediterranean diet, have shown to treat various ailments due to their remarkable antioxidant properties., Objective: The present study investigates the hepatoprotective effects of OO and its phenolic compounds HT and TY against TCDD-induced hepatotoxicity in male Wistar rats., Materials and Methods: TCDD was administered at a dose of 100 ng/kg p.o. for 20 d. Administration of OO (10 ml/kg; oral), HT (0.5 mg/kg; oral), and TY (30 mg/kg; i.p) was started 5 d prior to TCDD administration, and continued for 25 d with or without TCDD administration. At the end of the experiment (25 d), blood was taken for biochemical analyses and liver for the measurement of macromolecular damages, antioxidant status, expressions of CYP1A1, and apoptotic factors., Results: TCDD administration resulted in significant (p < 0.05) increase in the level of hepatic stress markers ALT (101.6 ± 3.07 IU/l), AST (295.0 ± 3.0 IU/l), and ALP (266.66 ± 3.7 IU/l). Also, biochemical analyses of liver reported elevation in nitrite and protein carbonyl content and depletion of NQO1 and HO. However, OO, HT, and TY restored the antioxidant status. Protein expressions by Western Blot technique showed an increase in the level of CYP1A1 and Bax and a decreased level of Bcl-2 on TCDD treatment, and vice versa on OO, HT, and TY treatment., Discussion and Conclusion: Our work concludes that dietary supplementation of OO, HT, and TY could serve as a potential preventive drug for TCDD-induced hepatotoxicity.

Context: Sargassum has been used in traditional Chinese medicine since the eighth century AD to treat goiter. Sargassum wightii Greville (Sargassaceae) is a major source of alginic acid used widely in food and drug industries., Objective: To evaluate the anti-Alzheimer potential of S. wightii through evaluation of antioxidant and cholinesterase inhibitory activities., Materials and Methods: Successive extraction was done using solvents of varying polarity. Solvent extracts (100-500 µg/mL) were employed for all the antioxidant assays. Free radical scavenging activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl, OH•, H2O2 radical scavenging assay. The reducing power of the seaweed was evaluated by ferric reducing antioxidant power and reducing power assay. Cholinesterase (ChE) inhibitory activity was evaluated and the Km, Vmax and Ki were calculated. Further, compound characterization was done by GC-MS analysis., Results: The non-polar extracts were found to possess significant antioxidant activity. At 100 μg/mL, petroleum ether, hexane, benzene and dichloromethane extracts showed significant ChE inhibitory activity with IC50 values of 19.33 ± 0.56, 46.81 ± 1.62, 27.24 ± 0.90, 50.56 ± 0.90 µg/mL, respectively, for AChE, and 17.91 ± 0.65, 32.75 ± 1.00, 12.98 ± 0.31, 36.16 ± 0.64 µg/mL, respectively, for BuChE. GC-MS reveals that 1,2-benzenedicarboxylic acid, diisooctyl ester is the major compound present in dichloromethane extract of S. wightii. The mode of inhibition exhibited by dichloromethane extract against the cholinesterases was found to be competitive type., Discussion and Conclusion: The presence of high amount of terpenoids could be the possible reason for its potential antioxidant and ChE inhibitory activity.

Context: Epidemiological studies have shown that despite mortality due to communicable diseases, poverty and human conflicts, the incidence of dementia increases in the developing world in tandem with the ageing population. Although some FDA approved drugs are available for the treatment of dementia, the outcomes are often unsatisfactory. In traditional practices of medicine, numerous plants have been used to treat cognitive disorders, including neurodegenerative diseases such as Alzheimer's disease (AD) and other memory-related disorders. In western medicine most of the drugs used for the treatment of neurodegenerative disorders are derived from plant sources., Objective: This article reviews plants and their active constituents that have been used for their reputed cognitive-enhancing and antidementia effects., Methods: A literature survey in Science Direct, Pubmed, and Google Scholar was performed to gather information regarding drug discovery from plants sources for the treatment of congnitive disorders and dementia., Results: More than forty herbal remedies were identified with cholinesterase inhibitory, anti-inflammatory, or antioxidant activities. Bioactive compounds include alkaloids, flavonoids, steroids, saponins, terpenoids, and essential oils. About eleven herbal plants with multipotent activity against AD are discussed., Conclusion: Literature surveys show that most of the research has been conducted on herbal remedies effect on cholinesterase inhibitory and antioxidant activities. Studies regarding the effect of herbal drugs on β-secretase inhibitory activity and antiaggregation property are lacking. This review provides leads for identifying potential new drugs from plant sources for the treatment of neurodegenerative disorders.