The in vitro screening for acetylcholinesterase inhibition and antioxidant activity of medicinal plants from Portugal

Natural Peptides in Drug Discovery Targeting Acetylcholinesterase

Acetylcholinesterase-inhibitory peptide has gained much importance since it can inhibit acetylcholinesterase (AChE) and increase the availability of acetylcholine in cholinergic synapses, enhancing cholinergic transmission in pharmacological treatment of Alzheimer’s disease (AD). Natural peptides have received considerable attention as biologically important substances as a source of AChE inhibitors. These natural peptides have high potential pharmaceutical and medicinal values due to their bioactivities as neuroprotective and neurodegenerative treatment activities. These peptides have attracted great interest in the pharmaceutical industries, in order to design potential peptides for use in the prophylactic and therapy purposes. Some natural peptides and their derivatives have high commercial values and have succeeded in reaching the pharmaceutical market. A large number of peptides are already in preclinical and clinical pipelines for treatment of various diseases. This review highlights the recent researches on the various natural peptides and future prospects for AD management.

Synthesis and Evaluation of Biological Activity of New Arylphosphoramidates

The synthesis of new substituted arylphosphoramidates is performed in two steps through phosphorylation of the corresponding alcohols followed by aminolysis. The formation of the desired phosphoramidates depends on the subsequent addition of the two alcohols with the amine being added at the last step. The products were obtained in 58-95% yields. They were characterized mainly by multinuclear (¹H, ¹³C, ³¹P, and ¹⁹F) NMR and IR spectroscopy. In addition, the antimicrobial and antiacetylcholinesterase activities were evaluated. The results showed acetylcholinesterase activity by some compounds, whilst no significant inhibitory effect against the tested bacterial strains has been recorded.

Volatile Terpenes and Brain Function: Investigation of the Cognitive and Mood Effects of Mentha × Piperita L. Essential Oil with In Vitro Properties Relevant to Central Nervous System Function

Background: Extracts of several members of the monoterpene-rich Lamiaceae sub-family Nepetoideae, including those from the Salvia (sage), Melissa (Lemon balm) and Rosmarinus (rosemary) genera, evince cognitive and mood effects in humans that are potentially related to their effects on cholinergic and GABAergic neurotransmission. To date, despite promising in vitro properties, the cognitive and mood effects of the closely related Mentha spicata (spearmint) and Mentha piperita (peppermint) remain unexplored. This study therefore assessed the human cognitive/mood effects of the M. spicata/piperita essential oil with the most promising, brain-relevant in vitro properties according to pre-trial in vitro screening. Design: Organic spearmint and peppermint (Mentha spicata/piperita) essential oils were pre-screened for neurotransmitter receptor binding and acetylcholinesterase (AChE) inhibition. In a double-blind, placebo-controlled, balanced cross-over study, 24 participants (mean age 25.2 years) consumed single doses of encapsulated placebo and 50 µL and 100 µL of the most promising essential oil (peppermint with nicotinic/GABAA receptor binding and AChE inhibitory properties, that increased calcium influx in a CAD cell neuronal model). Psychological functioning was assessed with mood scales and a range of standardised, cognitively demanding tasks pre-dose and at 1, 3 and 6 h post-dose. Results: The highest (100 µL) dose of essential oil improved performance on the cognitively demanding Rapid Visual Information Processing task (RVIP) at 1 h and 3 h post-dose and both doses attenuated fatigue and improved performance of the Serial 3 s subtraction task at 3 h post-dose. Conclusion: Peppermint (Mentha piperita) essential oil with high levels of menthol/menthone and characteristic in vitro cholinergic inhibitory, calcium regulatory and GABA_A/nicotinic receptor binding properties, beneficially modulated performance on demanding cognitive tasks and attenuated the increase in mental fatigue associated with extended cognitive task performance in healthy adults. Future investigations should consider investigating higher doses.

The Confrontation between Ethnopharmacology and Pharmacological Tests of Medicinal Plants Associated with Mental and Neurological Disorders

For neurological disorders, pharmacological tests have shown promising results in the reduction of side effects when using plants with known therapeutic effects in the treatment of some types of dementia. Therefore, the goals of this study are to gather data about the major medicinal plants used in the nervous system as described in ethnopharmacological surveys from South America and Brazil and to compare this data with the results from pharmacological tests on the active principles of those same plants found in the scientific literature. After collecting the data about each plant, their respective popular indication was compared with the results found through pharmacological tests. The discrepancy rate between the effects observed by ethnopharmacological and pharmacological methods in this study is greater than 50%. In conclusion, despite the importance of ethnopharmacological data, it is important to make comparisons with pharmacological tests for the same plants, since the pharmacological studies, although few, have shown a high rate of discrepancy in the results.

Phenolic Composition and Bioactivity of Lavandula pedunculata (Mill.) Cav. Samples from Different Geographical Origin

The aim of this study was to characterize the phenolic composition and evaluate the bioactivity of several samples of Lavandula pedunculata (Mill.) Cav, and to compare aqueous and hydroethanolic extracts. Plant materials were obtained by growing some accessions (seed samples) of various wild populations from different regions of Portugal conserved at the Portuguese Genebank in Braga. Phenolic compounds were analised by HPLC-DAD-ESI/MSn, antioxidant potential through in vitro assays (DPPH radical scavenging activity, reducing power and inhibition of lipid peroxidation), cytotoxicity on tumor cells (MCF-7, NCI-H460, HeLa and HepG2) and non-tumor (PLP2) cells, anti-inflammatory activity in rat RAW 264.7 macrophages, by the ability to inhibit NO production and antimicrobial potential by the microdilution method with INT dye (iodonitrotetrazolium chloride). Thirteen compounds were identified, being salvianolic acid B, rosmarinic acid and luteolin-7-O-glucuronide, the main compounds present, with values ranging between 44.3–582, 50.9–550, and 24.36–101.5 mg/g extract, respectively. L. pedunculata aqueous extract revealed a higher antioxidant potential (EC₅₀ values between 14 to 530 μg/mL), which could be related to its higher concentration in phenolic compounds; however, the hydroethanolic extract showed a higher anti-inflammatory (lower EC₅₀ values than 124 μg/mL) potential and antiproliferative capacity (lower GI₅₀ values than 34 μg/mL). Thus, this study highlights the bioactive effects of this species and opens up possibilities of uses in food and pharmaceutical formulations. However, there are potential differences in such properties according to geographical origin of plant material, as in general, the samples from Alentejo presented higher results in all the bioactivities, compared with Trás-os-Montes samples.

In Vitro Protection by Crataegus microphylla Extracts Against Oxidative Damage and Enzyme Inhibition Effects

Objectives

Crataegus species have been used as food and also in folk medicine for the treatment of various diseases. The present study aimed to make investigations on the biologic properties of different extracts prepared from Crataegus microphylla C. Koch, which was collected from Turkey.

Materials and Methods

Dried leaf, stem bark, and fresh fruit samples of C. microphylla were separated and ethanol extract, acidified (0.5% HCl, pH: 2.5) ethanol extract, ethanol:water (1:1) extract, methanol extract, acidified (0.5% HCl, pH: 2.5) methanol extract, methanol:water (1:1) extract, water extract, and acidified (0.5% HCl, pH: 2.5) water extract were prepared for each. Various biologic effects such as the prevention of oxidative DNA damage, acetylcholinesterase, tyrosinase, α-glucosidase inhibition, and antioxidant effects with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, PRAP, and FRAP assays of these extracts at different concentrations were studied.

Results

Acidified methanol extract of stem barks exhibited the highest acetylcholinesterase and tyrosinase inhibitions among the other extracts with IC₅₀ values of 204.02±0.95 μg/mL and 37.30±0.27 μg/mL, respectively. Acidified ethanol extract of leaves was the most efficient extract against α-glucosidase, giving an IC₅₀ of 15.78±0.14 μg/mL. The IC₅₀ value of the acidified ethanol extract for DPPH was 9.89±0.09 µg/mL. Methanol extracts of leaves and stem barks at the dose of 125 µg/mL exhibited significant protective activity against DNA strand scission by hydroxyl radicals (.OH) on supercoiled pBR322 DNA.

Conclusion

Acidified methanol or ethanol extracts prepared with stem bark and leaf from C. microphylla have potential antioxidant, hypoglycemic, and neuroprotective effects.

Chemical composition, antioxidant potential, macromolecule damage and neuroprotective activity of Convolvulus pluricaulis

Herbal medicines are known to mitigate radical induced cell damage. Hence identification and scientific validation of herbal medicines contribute to better use in Ayurvedic/Unani research. In the present study, we investigated antioxidant and anti-apoptotic properties of Convolvulus pluricaulis (C. pluricaulis). C. pluricaulis exhibited antioxidant potential evident by free radical scavenging activities. C. pluricaulis pretreatment inhibited H₂O₂ induced macromolecule damage such as plasmid DNA damage and AAPH induced oxidation of bovine serum albumin and lipid peroxidation of rat hepatic tissues. Further to identify the neuroprotective properties of C. pluricaulis, SHSY5Y cells were treated with H₂O₂ with or without pretreatment of C. pluricaulis. The C. pluricaulis pretreatment at 50 μg/ml dose exhibited 50% cell survival against 100 μM H₂O₂ challenge for 24 h and it also decreased the lactate dehydrogenase leakage. Further C. pluricaulis pretreatment restored and regulated the antioxidant and apoptosis markers such as SOD, CAT, p53, and caspase-3 and inhibited, reactive oxygen species generation and depolarization of the mitochondrial membrane. C. pluricaulis possess a high content of flavonoids and polyphenols and GC-MS and FTIR analysis showed a wide variety of compounds which may contribute to the observed effects.

Anti-inflammatory, anti-cholinergic and cytotoxic effects of Sida rhombifolia

CONTEXT

Sida (Malvaceae) has been used as a traditional remedy for the treatment of diarrhoea, malarial, gastrointestinal dysentery, fevers, asthma and inflammation.

OBJECTIVES

This study evaluates the anti-inflammatory, cytotoxic and anti-cholinergic activities of Sida rhombifolia Linn. whole plant for the first time.

MATERIALS AND METHODS

S. rhombifolia whole plant was extracted by n-hexane, ethyl acetate and methanol using Soxhlet apparatus. The plant extracts were evaluated for their antioxidant (DPPH, FIC and FRAP), anti-inflammatory (NO and protein denaturation inhibitions), cytotoxic (MTT) and anti-cholinesterase (AChE) properties in a range of concentrations to obtain IC₅₀ values. GC-MS analysis was carried out on the n-hexane extract.

RESULTS AND DISCUSSION

The ethyl acetate extract exhibited the most significant antioxidant activities by scavenging DPPH radicals and ferrous ions with EC₅₀ of 380.5 and 263.4 μg/mL, respectively. In contrast, the n-hexane extract showed the strongest anti-inflammatory activity with IC₅₀ of 52.16 and 146.03 μg/mL for NO and protein denaturation inhibition assays, respectively. The same extract also revealed the strongest effects in anti-cholinesterase and cytotoxic tests at the concentration of 100 μg/mL, AChE enzyme inhibition was 58.55% and human cancer cells, SNU-1 and Hep G2 inhibition was 68.52% and 47.82%, respectively. The phytochemicals present in the n-hexane extract are palmitic acid, linoleic acid and γ-sitosterol.

CONCLUSIONS

The present study revealed that the n-hexane extract possessed relatively high pharmacological activities in anti-inflammation, cytotoxicity and anti-cholinesterase assays. Thus, further work on the detail mechanism of the bioactive phytochemicals which contribute to the biological properties are strongly recommended.

In vitro digestion, antioxidant and antiacetylcholinesterase activities of two species of Ruta: Ruta chalepensis and Ruta montana

CONTEXT

Ruta genus (Rutaceae) is abundantly used and described in the most ancient systematic records of medical practice of the Mediterranean world. In Tunisia, this genus is represented by two medicinal and aromatic shrubs: Ruta chalepensis L. and Ruta montana L.

OBJECTIVE

This study investigates the antioxidant and acetylcholinesterase inhibition (AChE) activities before and after in vitro gastrointestinal metabolism of leaf decoction of R. chalepensis and R. montana.

MATERIALS AND METHODS

We study, in vitro, the effect of the gastrointestinal juices gastric (1.75 mL) or pancreatic (2.5 mL) juices, on the biological activity by the measurement of the antioxidant activity and AChE inhibition during 4 h of decoction extract obtained from the leaves of the two species of Ruta.

RESULTS

The results showed that the ability to inhibit the AChE enzyme was similar; being the greatest inhibitory activity exhibited by the ethanol extract (IC₅₀=12 ± 1.1 μg/mL) obtained from leaves of R. chalepensis.

CONCLUSION

In conclusion, we showed that there was no appreciable degradation and that the activity was kept constant after gastric and pancreatic juice digestion.

In vitro antimicrobial potential of extracts and phytoconstituents from Gymnema sylvestre R.Br. leaves and their biosafety evaluation

The in vitro antimicrobial screening of Gymnema sylvestre leaves against 13 test pathogens established its broad spectrum activity with average inhibition zone ranging from 14 to 23 mm. The antimicrobial activity of the classically- optimized aqueous extract was enhanced up to 1.45 folds, when subjected to statistical optimization using Response Surface Methodology (RSM) and was thermostable. Ethyl acetate was found to be the best organic extractant with Klebsiella pneumoniae 1 (31.5 mm) and Staphylococcus epidermidis (25.5 mm) being the most sensitive among Gram negative and Gram positive bacteria, respectively. Among the major group of phytoconstituents detected, tannins were the most abundant followed by flavonoids and phytosterols, while triterpenes were absent. Flavonoids and cardiac glycosides exhibited a broad range of antimicrobial potential, with inhibition zone ranging from 13 to 35 mm, where Candida albicans was the most sensitive organism. Ethyl acetate extract showed better potency with lowest Minimum inhibitory concentration (0.1–1 mg ml⁻¹) than the aqueous extract (1–3 mg ml⁻¹) and all partially purified phytoconstituents (0.1–10 mg ml⁻¹). The ethyl acetate extract and flavonoids were highly potent, as they exhibited a total activity potency ranging from 41.4 to 1045 ml g⁻¹. Time kill studies revealed their microbicidal action, where ethyl acetate extract had a kill time from 0 to 12 h. However, among phytoconstituents, flavonoids were the most effective (0–8 h). The MIC and time kill study was also compared to that of standard antibiotics. These findings indicate that Gymnema sylvestre can be a potential source for development of leading metabolites against pathogens of clinical importance like Pseudomonas aeruginosa, Candida albicans, Escherichia coli, Staphylococcus aureus etc. They were neither mutagenic nor cytotoxic, as revealed by Ames and MTT assay.

Modulation of some markers of erectile dysfunction and malonaldehyde levels in isolated rat penile tissue with unripe and ripe plantain peels: identification of the constituents of the plants using HPLC

CONTEXT

Plantain fruit pulp has been used as a natural remedy to manage erectile dysfunction (ED) in traditional medicine. However, the potency of the peel has not been examined with respect to ED management.

OBJECTIVE

This study investigated and compared the inhibitory potential of unripe (UPP) and ripe (RPP) plantain peels on some enzymes associated with ED and Fe²⁺-induced oxidative stress in albino rat penile homogenate in vitro.

MATERIALS AND METHOD

Aqueous extract of the peels was prepared and the effect on phosphodiesterase-5 (PDE-5), arginase, acetylcholinesterase (AChE), angiotensin-I converting enzyme (ACE) and Fe²⁺-induced malonyladehyde in isolated albino rat penile homogenate were investigated. Phenolic constituents of the peels powder were characterized using high-performance liquid chromatography coupled with diode array detector (HPLC-DAD).

RESULT

Extract from UPP had higher PDE-5 (IC₅₀ = 3.10 μg/mL), arginase (IC₅₀ = 0.96 μg/mL), AChE (IC₅₀ = 6.30 μg/mL) and ACE (IC₅₀ = 0.41 μg/mL) inhibitory ability compared with RPP (PDE-5, IC₅₀ = 4.33 μg/mL; arginase, IC₅₀ = 1.34 μg/mL; AChE, IC₅₀ = 8.64 μg/mL; ACE, IC₅₀ = 0.63 μg/mL). The extract from UPP also had higher inhibition of Fe²⁺-induced lipid peroxidation. HPLC-DAD analysis revealed that gallic and caffeic acids, rutin, quercitrin and quercetin were abundant in UPP, while catechin, kaempferol, chlorogenic and ellagic acids were the dominant phenolic compounds in RPP.

DISCUSSION AND CONCLUSION

Inhibition of enzymes associated with ED and lipid peroxidation could be linked with the phenolic compounds. However, UPP appeared to be more potent.

Antioxidant capacity and phenolic content of two Algerian Mentha species M. rotundifolia (L.) Huds, M. pulegium L., extracted with different solvents

Background It is important to consider the optimum conditions and processing factors (like solvent type) influencing activity of plant antioxidants for utilization in food and biological systems. Methods The antioxidant capacity and phenolic content of two Mentha species, namely, Mentha pulegium L. (MP) and Mentha rotundifolia (L.) Huds (MR), were studied and six solvent systems were used. The total antioxidant capacity of the mint species extracts was evaluated using phosphomolybdenum method and the free radical-scavenging capacity by 2,2-diphenyl-1-picrylhydrazyl radical-scavenging assay. Results The efficiency of the used solvents to extract phenols from the two species varied considerably. The highest total phenolic content was obtained from methanol extract of MP (25.3±1.3 mg GAE/gdw) and total flavonoid content from methanol extract of MR (10.1±0.1 mg QE/gdw). High phenol content was significantly correlated with high antioxidant capacity. The methanol extracts showed the highest radical scavenging activity. All the extracts showed variable antioxidant capacity by the formation of phosphomolybdenum complex. Acetone extract of MP and methanol extract of MR exhibited marked reducing power in this method. Conclusions Our findings identified the appropriate solvent for extracting MP and MR phenolics which might provide a rich source of natural antioxidants.

Melissa officinalis L: A Review Study With an Antioxidant Prospective

Melissa officinalis is a plant cultivated in some parts of Iran. The leaves of lemon balm, Melissa officinalis L (Lamiaceae), are used in Iranian folk medicine for their digestive, carminative, antispasmodic, sedative, analgesic, tonic, and diuretic properties, as well as for functional gastrointestinal disorders. This review article was aimed not only to introduce Melissa officinalis (its growth condition, its chemical compounds, and its traditional usages) but also to overview its antioxidant properties in detail. This review was carried out by searching studies in PubMed, Medline, Web of Science, and IranMedex databases up to 2016. The search terms used were " Melissa officinalis L," "antioxidant properties," oxidative stress," "oxidative damage", "ROS." Articles whose full texts were not available were excluded from the study. In this study, firstly, traditional usage of this herb was reviewed, including antimicrobial activity (antiparasitic, antibacterial, antiviral, etc), antispasmodic, and insomnia properties. Then, its antioxidant properties were overviewed. Various studies have shown that Melissa officinalis L possesses high amount of antioxidant activity through its chemical compounds including high amount of flavonoids, rosmaric acid, gallic acid, phenolic contents. Many studies confirmed the antioxidative effects of Melissa officinalis; thus, its effect in preventing and treating oxidative stress-related diseases might be reliable.

Total phenolics, antioxidant, antitumor, and enzyme inhibitory activity of Indian medicinal and aromatic plants extracted with different extraction methods

The phenolic content, antioxidant, antitumor, and enzyme inhibitory activities of commonly used medicinal herbs from a Unani system of medicine were investigated using four different extraction methods. Among the plants studied, the Hyssopus officinalis L, Origanum vulgare L, and Portulaca oleracea L. extracts showed the highest amount of total phenolics (64.40, 60.35, and 58.81 mg GAE/g) and revealed significant antioxidant activities. The plants also showed a maximum cytotoxic activity as indicated by H. officinalis (82%), O. vulgare (75%), and P. oleracea (72%) showed more than 70% cytotoxicity for breast cancer cells, 82% of the cells were dead at the concentration of 500 mg/mL. The plants H. officinalis, P. oleracea, O. vulgare, and Rubia cordifolia L. revealed more than 80% inhibition towards xanthine oxidase and comprising maximum 70% of inhibition for superoxide dismutase. From results we conclude that there is a strong correlation between phenolic content, antioxidant, and enzyme inhibitory activity among these plants, indicating phenolics are the major compounds for these biological activities. Furthermore, this study provides the basis for the therapeutic importance of studied plants as latent inhibitors of oxidative stress and antitumor cell proliferation which correlate with the ethnobotanical data contained in the Unani system of medicine.

The role of dietary polyphenols in the management of erectile dysfunction-Mechanisms of action

The incidence of erectile dysfunction (ED) is on the increase and it is estimated that it will affect about 322 million men globally by the year 2025 if adequate measures are not taken to curb it. Natural polyphenols in plant based diets have gained public interest in recent times due to their roles in the prevention of various disease that implicate free radicals/reactive oxygen species and recently on ED. However, the role of polyphenols in the management of ED has not been explored due perhaps to limited data available. Hence this study which reviewed the role of dietary polyphenols in the management of ED and their mechanisms of action. Literature search was carried out in several electronic data bases such as Pubmed, Google Scholar, Medline, Agora and Hinari from1972 to 2016 to identify the current status of knowledge on the role of polyphenols in the management of erectile dysfunction. Progress made so far in this direction suggests inhibition of arginase, acetylcholinesterase, angiotensin converting enzyme, rho-kinase II; activation of endothelial and neuronal NO synthase; decreased synthesis of luteinizing hormone and testosterone reduction; activation of silent information regulator 2-related enzymes (sirtuin1) as well as free radical/reactive oxygen species inhibition as the mechanisms through which the polyphenols identified in this review exert beneficial roles in the management of ED.

Traditional Uses, Chemical Constituents and Biological Activities of Plants from the Genus Sanguisorba L

Plants from the genus Sanguisorba have been treated as medicinal ingredients for over 2000 years. This paper reviews advances in the botanical, phytochemical and pharmacological studies of the genus. To date, more than 120 chemical constituents have been isolated and identified from these plants, especially from S. officinalis and S. minor. Among these compounds, triterpenoids, phenols and flavonoids are the primary biologically active constituents. Triterpenoids can be used as quality control markers to determine the quality of medicinal materials and their preparations. In vivo and in vitro studies have shown that plants from the genus Sanguisorba exhibit a wide range of pharmacological properties, including hemostatic, antibacterial, antitumor, neuroprotective and hypoglycemic activities. In Chinese medical practice, many drugs (e.g., tablets and powders) that contain S. officinalis roots have been used to treat leukopenia, hemorrhaging and burns. However, there is still a multitude of Sanguisorba species that have garnered little or no attention. Indeed, there are few reports concerning the clinical use and toxic effects of these plants. Further attention should be focused on the study of these species in order to gather information on their respective toxicology data, any relevant quality-control measures, and the clinical value of the crude extracts, active compounds, and bioactive metabolites from Genus Sanguisorba.

Potential benefits of phytochemicals against Alzheimer's disease

Our current therapeutic drugs for Alzheimer's disease are predominantly derived from the alkaloid class of plant phytochemicals. These drugs, such as galantamine and rivastigmine, attenuate the decline in the cholinergic system but, as the alkaloids occupy the most dangerous end of the phytochemical spectrum (indeed they function as feeding deterrents and poisons to other organisms within the plant itself), they are often associated with unpleasant side effects. In addition, these cholinesterase inhibiting alkaloids target only one system in a disorder, which is typified by multifactorial deficits. The present paper will look at the more benign terpene (such as Ginkgo biloba, Ginseng, Melissa officinalis (lemon balm) and Salvia lavandulaefolia (sage)) and phenolic (such as resveratrol) phytochemicals; arguing that they offer a safer alternative and that, as well as demonstrating efficacy in cholinesterase inhibition, these phytochemicals are able to target other salient systems such as cerebral blood flow, free radical scavenging, anti-inflammation, inhibition of amyloid-β neurotoxicity, glucoregulation and interaction with other neurotransmitters (such as γ-aminobutyric acid) and signalling pathways (e.g. via kinase enzymes).

Assessment of in-vitro cholinesterase inhibitory and thrombolytic potential of bark and seed extracts of Tamarindus indica (L.) relevant to the treatment of Alzheimer's disease and clotting disorders

BACKGROUND

Low level of acetylcholine (ACh) is an important hallmark of Alzheimer's disease (AD), a common type of progressive neurodegenerative disorder. Effective treatment strategies rely mostly on either enhancing the cholinergic function of the brain by improving the level of ACh from being a breakdown by cholinesterase enzymes. Again atherothrombosis is major life-threatening cerebral diseases. Traditionally Tamarindus indica (L.) has widely known for its medicinal values. Our aim is to investigate the cholinesterase inhibitory activities as well as thrombolytic activities of the bark and seeds crude methanolic extracts (CMEs) in the treatment of AD and clotting disorder.

MATERIALS AND METHODS

The crude methanol extract was prepared by cold extraction method and was assessed for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities by the Ellman's method. For thrombolytic activity clot lysis method was applied.

RESULTS

To compare both the fractions, extracts from the bark got more AChE inhibitory activity than the seed with the inhibitory concentration 50% IC50 values of 268.09 and 287.15 µg/ml, respectively. The inhibitory activity of BuChE was quiet similar to that of AChE as IC50 values of both the fractions were 201.25 and 254.71 µg/ml. Again in-vitro thrombolytic activity of bark was 30.17% and of seed it was 22.53%.

CONCLUSION

The results revealed that the CME of bark and seed both have moderate cholinesterases inhibitory activities as well as thrombolytic activities, worth of further investigations to identify the promising molecule(s) potentially useful in the treatment of AD as well as in clotting disorders.

Chemical Composition, Antioxidant and Antimicrobial Activities of Sanguisorba officinalis L. Extracts

Sanquisorba officinalis has been used internally for the treatment of intestinal infections and duodenal ulcers, as well as hemorrhoids, phlebitis and varicose veins and female disorders, and topically to heal wounds, burns, and ulcers. In our study, the antioxidant and antimicrobial activities, as well as quantitative analysis of polyphenols (phenolic acids, flavonoids and total polyphenols) in methanol and aqueous extracts from S. officinalis herbs are presented. A correlation between the antioxidant activity and composition of tested extracts indicates that flavonoids are the major compounds causing scavenging of free radicals. Higher content of flavonoids was found in the methanol extract, while the content of total phenolics was higher in the aqueous extract. Both extracts from S. officinalis herbs showed antioxidant activity and high antimicrobial activity in a wide spectrum of test strains.

Melissa officinalis L. - A review of its traditional uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L. is a medicinal plant that has long been used in different ethno-medical systems especially in the European Traditional Medicine and the Iranian Traditional Medicine for the treatment of several diseases. It is also widely used as a vegetable and to add flavor to dishes

AIM OF THE REVIEW

This review aimed to provide a summary on the botanical characterization, traditional uses, phytochemistry, pharmacological activities, pharmacokinetics and toxicity of M. officinalis, and discusses research gaps and future opportunities for investigations on this plant.

MATERIALS AND METHODS

We extensively reviewed major unpublished old texts, and published and electronic literature on traditional medicines of different regions of the world to find traditional uses of M. officinalis. Electronic databases including Web of Science, PubMed, ScienceDirect, Google Scholar and Scopus were searched to find articles (published between 1956 and 2015) on pharmacology and phytochemistry of M. officinalis.

RESULTS

Traditional uses of M. officinalis have been recorded mostly in European countries, Mediterranean region and Middle East countries. Phytochemical investigations revealed that this plant contains volatile compounds, triterpenoids, phenolic acids and flavonoids. Crude extracts and pure compounds isolated from M. officinalis exhibited numerous pharmacological effects, from which only anxiolytic, antiviral and antispasmodic activities of this plant as well as its effects on mood, cognition and memory have been shown in clinical trials. AChE inhibitory activity, stimulation of the acetylcholine and GABAA receptors, as well as inhibition of matrix metallo proteinase-2 are the main mechanisms proposed for the widely discussed neurological effects of this plant.

CONCLUSIONS

Modern pharmacological studies have now validated many traditional uses of M. officinalis. The data reviewed here revealed that M. officinalis is a potential source for the treatment of a wide range of diseases especially anxiety and some other CNS disorders, though confirmatory trials are warranted to substantiate these effects in the clinical setting. Data regarding many aspects of this plant such as mechanisms of actions, pharmacokinetics, adverse effects of the extracts, potential interactions with standard-of-care medications and active compounds is still limited which call for additional studies particularly in humans.

An ethnomedicinal survey of a Tashelhit-speaking community in the High Atlas, Morocco

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional knowledge about medicinal plants from a poorly studied region, the High Atlas in Morocco, is reported here for the first time; this permits consideration of efficacy and safety of current practises whilst highlighting species previously not known to have traditional medicinal use.

AIM OF THE STUDY

Our study aims to document local medicinal plant knowledge among Tashelhit speaking communities through ethnobotanical survey, identifying preferred species and new medicinal plant citations and illuminating the relationship between emic and etic ailment classifications.

MATERIALS AND METHODS

Ethnobotanical data were collected using standard methods and with prior informed consent obtained before all interactions, data were characterized using descriptive indices and medicinal plants and healing strategies relevant to local livelihoods were identified.

RESULTS

151 vernacular names corresponding to 159 botanical species were found to be used to treat 36 folk ailments grouped in 14 biomedical use categories. Thirty-five (22%) are new medicinal plant records in Morocco, and 26 described as used for the first time anywhere. Fidelity levels (FL) revealed low specificity in plant use, particularly for the most commonly reported plants. Most plants are used in mixtures. Plant use is driven by local concepts of disease, including "hot" and "cold" classification and beliefs in supernatural forces.

CONCLUSION

Local medicinal plant knowledge is rich in the High Atlas, where local populations still rely on medicinal plants for healthcare. We found experimental evidence of safe and effective use of medicinal plants in the High Atlas; but we highlight the use of eight poisonous species.

Chemical composition, antioxidant, and enzyme inhibitory activities of the essential oils of three Phlomis species as well as their fatty acid compositions

This study aimed to investigate the chemical composition, antioxidant, and enzyme inhibitory activities of the essential oils of Phlomis armeniaca WILLD., P. nissolii L., and P. pungens WILLD. var. pungens as well as their fatty acid contents. Germacrene D was found as the major compound in the oils (24.7, 15.1, and 7.2%, respectively). Additionally, n-hexadecanoic acid, hexahydrofarnesyl acetone, β-caryophyllene, and linalool were the other main compounds in the oils. Among the fatty acids, C18:3 ω3 and C18:2 ω6 were determined in high quantities in P. armeniaca (23.14 and 18.01%, respectively) and P. pungens var. pungens (24.64 and 17.51%, respectively). The essential oils of P. armeniaca and P. pungens var. pungens showed remarkable antioxidant and metal chelating activities as well as great reducing power potentials. These oils also showed a moderate scavenging effect on ABTS radicals. The oils also exhibited various degrees of inhibitory activities on AChE, BChE, α-amylase, α-glucosidase, and tyrosinase.

Phytochemical Composition and Biological Activities of Selected Wild Berries (Rubus moluccanus L., R. fraxinifolius Poir., and R. alpestris Blume)

Berries, from the genus Rubus, are among the vital components in a healthy diet. In this study, 80% methanol extracts from the three wild Rubus species (Rubus moluccanus L., Rubus fraxinifolius Poir., and Rubus alpestris Blume) were evaluated for their phytochemical contents (total phenolics, flavonoid, anthocyanin, and carotenoid content), antioxidant (DPPH, FRAP, and ABTS assays), antiacetylcholinesterase, and antibacterial activities. GC-MS was used for quantification of naturally occurring phytochemicals. The results showed that R. alpestris contained the highest total phenolic [24.25 ± 0.1 mg gallic acid equivalent (GAE)/g] and carotenoid content [21.86 ± 0.63 mg β-carotene equivalents (BC)/g], as well as the highest DPPH scavenging and FRAP activities. The highest total flavonoid [18.17 ± 0.20 mg catechin equivalents (CE)/g] and anthocyanin content [36.96 ± 0.39 mg cyanidin-3-glucoside equivalents (c-3-gE)/g] have been shown by R. moluccanus. For antibacterial assays, R. moluccanus and R. alpestris extracts showed mild inhibition towards Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Salmonella enteritidis. Anticholinesterase activity for all extracts was in the range of 23-26%. The GC-MS analysis revealed the presence of at least 12, 21, and 7 different organic compounds in 80% methanol extracts of R. alpestris, R. moluccanus, and R. fraxinifolius, respectively, which might contribute to the bioactivity.

Evaluation of antioxidant, enzyme inhibition, and cytotoxic activity of three anthraquinones (alizarin, purpurin, and quinizarin)

OBJECTIVE

The aim of this work was to investigate the cytotoxic, antioxidative, and enzyme inhibition effects of alizarin, quinizarin, and purpurin, which are anthraquinones (AQ).

METHODS

Cytotoxic effects were evaluated with cell inhibition rate by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide assay. Different chemical assays, including free radical scavenging activity (1,1-diphenyl-2-picrylhydrazyl and 2,2-azino-bis(3-ethylbenzothiazloine-6-sulfonic acid)), phosphomolybdenum and reducing power (ferric reducing antioxidant power and cupric ion reducing activity), were used to evaluate the antioxidant properties. Moreover, enzyme inhibitory activities were analyzed against acetylcholinesterase, butrylcholinesterase, tyrosinase, α-amylase, and α-glucosidase.

RESULTS

These components have antioxidant and enzyme inhibition activity. Especially, purpurin showed the strongest antioxidant and good enzyme inhibitory effects. According to our cytotoxicity results, alizarin, purpurin, and quinizarin induced dose- and time-dependent cell proliferation. Furthermore, when we applied AQs with mitomycin C (MC) on L929 cell line, we demonstrated that cell proliferation in MC-AQ groups compared with MC group was increased. The most effective component was alizarin at 100 µM concentration. These AQs showed positive effects on L929 cell lines with high half-maximal inhibitory concentration values.

CONCLUSION

Our results demonstrate that AQs may be used as antioxidative compounds in food and medicinal applications.

Antioxidant activity, acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum extracts

In this study several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol), respectively. Moreover, for each type of the prepared extracts of P. officinalis and of C. umbellatum the content in the biologically active compounds – polyphenols, flavones and proanthocyanidins was determined. The antioxidant activity was assessed using two methods, namely the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reducing power assay. The analyzed plant extracts showed a high acetylcholinesterase and tyrosinase inhibitory activity in the range of 72.24–94.24% (at the highest used dose – 3 mg/mL), 66.96% and 94.03% (at 3 mg/mL), respectively correlated with a high DPPH radical inhibition – 70.29–84.9% (at 3 mg/mL). These medicinal plants could provide a potential natural source of bioactive compounds and could be beneficial to the human health, especially in the neurodegenerative disorders and as sources of natural antioxidants in food industry.

Alkaloid profiles and acetylcholinesterase inhibitory activities of Fumaria species from Bulgaria

GC-MS analysis of alkaloid profiles of five Fumaria species, naturally grown in Bulgaria (F. officinalis, F. thuretii, F. kralikii, F. rostellata and F. schrammii) and analysis of acetylcholinesterase inhibitory activity of alkaloid extracts were performed. Fourteen isoquinoline alkaloids were identified, with the principle ones being protopine, cryptopine, sinactine, parfumine, fumariline, fumarophycine, and fumaritine. Protopine contents, defined by HPLC analysis varied between 210.6 ± 8.8 μg/g DW (F. schrammii) and 334.5 ± 7.1 μg/g DW. (F. rostellata). While all of the investigated alkaloid extracts significantly inhibited acetylcholinesterase activity, the F. kralikii demonstrated the highest level of inhibition (IC50 0.13 ± 0.01 mg extract/mL).

Phenolic composition, antioxidant and enzyme inhibitory activities of ethanol and water extracts of Chenopodium botrys

In this study, we aimed to evaluate the phenolic composition, antioxidant, and enzyme inhibitory activities of ethanol and water extracts of Chenopodium botrys L.

Lathyrus aureus and Lathyrus pratensis: characterization of phytochemical profiles by liquid chromatography-mass spectrometry, and evaluation of their enzyme inhibitory and antioxidant activities

This study suggest that Lathyrus species may be further used in phytopharmaceuticals or food industry applications.

The effects of Melissa officinalis (lemon balm) pretreatment on the resistance of the heart to myocardial injury

CONTEXT

The antihyperlipidemic, antiarrhythmic, neuroprotective and hepatoprotective effects of Melissa officinalis L. (Lamiaceae) have been reported. However, no study has examined its effects on the resistance of the heart to stressful conditions.

OBJECTIVE

The objective of this study is to evaluate the effects of aqueous extract of M. officinalis aerial parts on Wistar rat heart with/without cardiac injury.

MATERIALS AND METHODS

Animals were grouped as control, isoproterenol (ISO), M. officinalis without (M50, M100, and M200) and with isoproterenol (M50 + ISO, M100 + ISO, and M200 + ISO). The aqueous extract of M. officinalis was orally administered at dosages of 50, 100, and 200 mg/kg/d, respectively, for 7 consecutive days. On the 6th and 7th day, ISO, M50 + ISO, M100 + ISO, and M200 + ISO groups received 85 mg/kg of isoproterenol for myocardial injury induction. On day 8, hemodynamic parameters were recorded and samplings were done.

RESULTS

The extract (50, 100, and 200 mg/kg) significantly reduced the heart rate (264 ± 5, 259 ± 5 and 281 ± 3 versus 377 ± 13 in control group, p < 0.01). Blood pressure was significantly decreased in M50 + ISO (75 ± 5) versus M50 (110 ± 6) and M100 + ISO (72 ± 6) versus M100 (105 ± 5 mmHg, p < 0.01). The malondialdehyde levels of the injured hearts were lower in M50 + ISO and M100 + ISO groups than in the ISO group (p < 0.05). Serum cardiac troponin I was higher in the M200 + ISO group (5.1 ± 1.7) than in the ISO group (2.7 ± 0.7 ng/ml, p < 0.05).

CONCLUSION

The lower dose of extract, by improving the balance of the redox system and by reducing the heart rate, may increase the heart resistance to injury. However, the higher doses of extract may intensify the injury of ischemic heart.

Phenolic Extract from Moringa oleifera Leaves Inhibits Key Enzymes Linked to Erectile Dysfunction and Oxidative Stress in Rats' Penile Tissues

This study was designed to determine the antioxidant properties and inhibitory effects of extract from Moringa oleifera leaves on angiotensin-I-converting enzyme (ACE) and arginase activities in vitro. The extract was prepared and phenolic (total phenols and flavonoid) contents, radical (nitric oxide (NO), hydroxyl (OH)) scavenging abilities, and Fe²⁺-chelating ability were assessed. Characterization of the phenolic constituents was done via high performance liquid chromatography-diode array detection (HPLC-DAD) analysis. Furthermore, the effects of the extract on Fe²⁺-induced MDA production in rats' penile tissue homogenate as well as its action on ACE and arginase activities were also determined. The extract scavenged NO^∗, OH^∗, chelated Fe²⁺, and inhibited MDA production in a dose-dependent pattern with IC₅₀ values of 1.36, 0.52, and 0.38 mg/mL and 194.23 µg/mL, respectively. Gallic acid, chlorogenic acid, quercetin, and kaempferol were the most abundant phenolic compounds identified in the leaf extract. The extract also inhibited ACE and arginase activities in a dose-dependent pattern and their IC₅₀ values were 303.03 and 159.59 µg/mL, respectively. The phenolic contents, inhibition of ACE, arginase, and Fe²⁺-induced MDA production, and radical (OH^∗, NO^∗) scavenging and Fe²⁺-chelating abilities could be some of the possible mechanisms by which M. oleifera leaves could be used in the treatment and/or management of erectile dysfunction.

Phenolic, flavonoid contents, anticholinesterase and antioxidant evaluation of Iris germanica var; florentina

This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman's assay. Antioxidant activity was performed using DPPH, H2O2 and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC50 values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC50 of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC50 = 9 μg/mL) and 78.30% (IC50 = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC50 values of < 0.1, 2, 2 and 3 μg/mL, respectively.