Search

Biological activities of six under-utilized medicinal leafy vegetable plants indigenous to Africa, i.e., Basella alba, Crassocephalum rubens, Gnetum africanum, Launaea taraxacifolia, Solanecio biafrae, and Solanum macrocarpon, were investigated via two independent techniques. The total phenolic content (TPC) was determined, and six microtiter plate assays were applied after extraction and fractionation. Three were antioxidant in vitro assays, i.e., ferric reducing antioxidant power (FRAP), cupric reduction antioxidant capacity (CUPRAC), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, and the others were enzyme (acetylcholinesterase, butyrylcholinesterase, and tyrosinase) inhibition assays. The highest TPC and antioxidant activity from all the methods were obtained from polar and medium polar fractions of C. rubens, S. biafrae, and S. macrocarpon. The highest acetyl- and butyrylcholinesterase inhibition was exhibited by polar fractions of S. biafrae, C. rubens, and L. taraxacifolia, the latter comparable to galantamine. The highest tyrosinase inhibition was observed in the n-butanol fraction of C. rubens and ethyl acetate fraction of S. biafrae. In vitro assay results of the different extracts and fractions were mostly in agreement with the bioactivity profiling via high-performance thin-layer chromatography–multi-imaging–effect-directed analysis, exploiting nine different planar assays. Several separated compounds of the plant extracts showed antioxidant, α-glucosidase, α-amylase, acetyl- and butyrylcholinesterase-inhibiting, Gram-positive/-negative antimicrobial, cytotoxic, and genotoxic activities. A prominent apolar bioactive compound zone was tentatively assigned to fatty acids, in particular linolenic acid, via electrospray ionization high-resolution mass spectrometry. The detected antioxidant, antimicrobial, antidiabetic, anticholinesterase, cytotoxic, and genotoxic potentials of these vegetable plants, in particular C. rubens, S. biafrae, and S. macrocarpon, may validate some of their ethnomedicinal uses. [ABSTRACT FROM AUTHOR]

• Insecticidal activity of 47 macroalgae mostly from Mediterranean Sea was examined. • Cholinesterase and tyrosinase inhibitory effect of the alga extracts was investigated. • D. dichotoma var. intricata was the only one exhibiting BChE inhibition over 50%. • BChE inhibition by four diterpenes in DDI was investigated in silico. • The macroalgae and their metabolites might be new sources of novel insecticides. Ethanolic extracts prepared from forty-seven macroalgae species collected from the Mediterranean Sea, Aegean Sea, and Sea of Marmara were tested at 200 μg/mL against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR), crucial for insect vivacity. Only one alga extract, e.g. Dictyota dichotoma var. intricata (C.Agardh) Greville 1830, had a notable inhibition of BChE (72.0 ± 0.07%), whereas the rest of the macroalgae possessed no or low inhibition of AChE (2.20 ± 0.39% - 14.20 ± 2.16%), BChE (0.62 ± 0.07% - 41.20 ± 3.07%), and TYR (< 10%). Several known diterpenes (isoamijiol, 14-deoxyamijiol, amijidictyol, dictyodial, and 4α-acetoxydictyodial) found earlier in this species were proceeded to molecular docking experiments to figure out its interactions with BChE. Eleven of the 47 macroalgal extracts were selected based on sufficient availability for testing in larvicidal and adulticidal activity assays against female Aedes aegypti "Orlando1952" the mosquito vector of yellow fever and dengue. The selected extracts displayed a high adulticidal activity ranging between 80–100% activity at 5 μg/mosquito. In contrast, only the ethanol extract of Ceramium siliquosum var. elegans showed larvicidal mortality of 93.3 ± 11.5% at 0.5 μg/mL. Our findings show that the macroalgae and their metabolites could be sources of novel insecticidal agents. [ABSTRACT FROM AUTHOR]

Ethnopharmacology has been an important starting point in medical and pharmaceutical sciences for discovering drug candidates from natural sources. In this regard, the genus Salvia L., commonly known as sage, is one of the best-known medicinal and aromatic plants of the Lamiaceae family; it has been recorded as being used for memory enhancement in European folk medicine. Despite the various uses of sage in folk medicines, the records that have pointed out sage's memory-enhancing properties have paved the way for the aforementioned effect to be proven on scientific grounds. There are many preclinical studies and excellent reviews referring to the favorable effect of different species of sage against the cognitive dysfunction that is related to Alzheimer's disease (AD). Hence, the current review discusses clinical studies that provide evidence for the effect of Salvia species on cognitive dysfunction. Clinical studies have shown that some Salvia species, i.e., hydroalcoholic extracts and essential oils of S. officinalis L. and S. lavandulaefolia leaves in particular, have been the most prominently effective species in patients with mild to moderate AD, and these species have shown positive effects on the memory of young and healthy people. However, the numbers of subjects in the studies were small, and standardized extracts were not used for the most part. Our review points out to the need for longer-term clinical studies with higher numbers of subjects being administered standardized sage preparations. [ABSTRACT FROM AUTHOR]

The EtOH extracts of the leaves of two new cultivars (Uysal-SFU and Turgut-SFT) of Salvia fruticosa Mill. was tested against acetylcholinesterase (IC50: 30.62 ± 3.27 and 32.97 ± 2.33 µg/mL for SFU and SFT, respectively) and butyrylcholinesterase (IC50: 69.91 ± 1.08 µg/mL and 86.55 ± 1.26 µg/mL), respectively, relevant to Alzheimer's disease. The essential oils showed a stumpy inhibition against AChE and no inhibition against BChE. DPPH radical scavenging activity of the extracts (86.70 ± 0.17% and 86.14 ± 1.13% for SFU and SFT, respectively) was stronger than that of quercetin (85.51 ± 0.17%): Their (1.24 ± 0.05 and 1.04 ± 0.16 for SFU and SFT, respectively) ferric-reducing antioxidant power were close to that of the reference (e.g. quercetin, 1.42 ± 0.14). Molecular docking simulations were performed on their major monoterpenes. Our findings revealed that the leaf EtOH extracts of two cultivars are promising inhibitors of both AChE and BChE. [ABSTRACT FROM AUTHOR]

• There is a complex interplay between gut microbiota, nervous and immune system. • This relationship leads to introduce the concept of the gut-brain-immune axis. • Evidence reported the role of polyphenols in modulating the gut-brain-immune axis. • Polyphenols may be effective in management of gut-brain-immune axis-related diseases. Neurodegenerative disorders, particularly in the elderly population, represent one of the most pressing social and health-care problems in the world. Besides the well-established role of both oxidative stress and inflammation, alterations of the immune response have been found to be closely linked to the development of neurodegenerative diseases. Interestingly, various scientific evidence reported that an altered gut microbiota composition may contribute to the development of neuroinflammatory disorders. This leads to the proposal of the concept of the gut-brain-immune axis. In this scenario, polyphenols play a pivotal role due to their ability to exert neuroprotective, immunomodulatory and microbiota-remodeling activities. In the present review, we summarized the available literature to provide a scientific evidence regarding this neuroprotective and immunomodulatory effects and the interaction with gut microbiota of polyphenols and, the main signaling pathways involved that can explain their potential therapeutic application in neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Based on our continuous effort to investigate chemistry and biology of the plant secondary metabolites, we were able to isolate a glycosidal flavonoid 1 from the Wild Egyptian Artichoke. The activity of dihydromyricetin 3-O-rhamnoside (sin. dihydromyricitrin, ampelopsin 3-O-rhamnoside) (1) against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE); its absolute configuration using X-ray crystallography were determined for the first time. Inhibitory activity of 1 against AChE and BChE enzymes were determined using a slightly modified version of Ellman's method. Compound 1 was revealed to have a potent inhibition against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values of 0.070 ± 0.008 and 0.071 ± 0.004 mM, respectively, where IC50 values of the reference drug (galanthamine) were 0.023 ± 0.15 and 0.047 ± 0.91 mM. Compound 1 could be a promising molecule against Alzheimer's disease. [ABSTRACT FROM AUTHOR]

The use of Thymus species amongst the public and their importance in the scientific world is increasing day by day. In addition to being consumed as tea and spice, Thymus species are used as folk medicine for respiratory, digestive, skin, circulatory, genital, nervous, visual and urinary diseases. In this study, it was aimed to examine the essential oil and ethanol extract of the root and aerial parts of Thymus pubescens Boiss. et Kotschy ex Celak in the terms of their biological activity and chemical content. The phenolic content of the species was determined by LC-MS/MS, while triterpenoid content, the chemical composition of the essential oil as well as flavour was determined by GC–MS. In addition, their antioxidant and cytotoxic activities, as well as acetyl- (AChE) and butyrylcholinesterase (BChE), urease, tyrosinase, elastase, collagenase, HMG-CoA reductase and angiotensin-converting enzyme (ACE) inhibitory activities were studied. Thymol (53.33%) was determined as the major component in the essential oil, while β-fenchyl alcohol (43.87%) was determined as the major component of the flavour. According to the LC-MS/MS and GC–MS results, it was found that especially the aerial parts of the species have a high amount of rosmarinic acid (3875.76 µg analyte/g extract), quinic acid (2392.55), naringenin (970.39), oleanolic (92785.96) and ursolic (63373.32) acids. The essential oil of T. pubescens species was observed to show high activity in four antioxidant assays, e.g. inhibition of lipid peroxidation, DPPH and ABTS radical scavenging activity as well as CUPRAC, while the ethanol extracts showed moderate antioxidant activity. In enzyme inhibition assays, the aerial parts exerted marked BChE, elastase, and collagenase inhibitory activities (92.43±1.28%, 42.59±0.56, and 48.61±0.39 at 100 µg/mL, respectively). On the other hand, AChE, urease, tyrosinase, HMG-CoA reductase and ACE inhibitory activities of all extracts were from low to moderate levels. In particular, the aerial parts of the species displayed a high cytotoxic effect (vitality%: 6.82±0.01 at 200 µg/mL) in breast cancer (MCF-7) cell line. Due to its remarkable antioxidant capacity, high content of rosmarinic, oleanolic, and ursolic acids and especially BChE, elastase, and collagenase inhibitory activity, T. pubescens has the potential for using in food supplements, food preservatives, cosmetics, and pharmaceutical industries. [Display omitted] • The phenolic, triterpenoid and essential oil composition of Thymus pubescens determined by LC-MS/MS and GC–MS. • The high potential of butyryl-cholinesterase, elastase, and collagenase inhibitory activities. • High ursolic acid and thymol content of Thymus pubescens. [ABSTRACT FROM AUTHOR]

Artemisinin (ART) is a bioactive compound isolated from the plant Artemisia annua and has been traditionally used to treat conditions such as malaria, cancer, viral infections, bacterial infections, and some cardiovascular diseases, especially in Asia, North America, Europe and other parts of the world. This comprehensive review aims to update the biomedical potential of ART and its derivatives for treating human diseases highlighting its pharmacokinetic and pharmacological properties based on the results of experimental pharmacological studies in vitro and in vivo. Cellular and molecular mechanisms of action, tested doses and toxic effects of artemisinin were also described. The analysis of data based on an up-to-date literature search showed that ART and its derivatives display anticancer effects along with a wide range of pharmacological activities such as antibacterial, antiviral, antimalarial, antioxidant and cardioprotective effects. These compounds have great potential for discovering new drugs used as adjunctive therapies in cancer and various other diseases. Detailed translational and experimental studies are however needed to fully understand the pharmacological effects of these compounds. [Display omitted] • Artemisinin (ART) is a bioactive compound isolated from the plant Artemisia annua. • ART has a great therapeutic potential for treating human chronic diseases. • Studies confirmed the effects in malaria, cancer, viral , bacterial infections and cardiovascular diseases. • ART has potential when is used as adjunctive therapies in cancer and other diseases. [ABSTRACT FROM AUTHOR]

The absolute configurations of the known but unusual spiro-flavostilbenoids found in the bark of Yucca schidigera Roezl ex Ortgies, were determined by applying time-dependent density functional theory simulation of electronic circular dichroism spectra. The absolute configurations obtained were as follows: (2 S ,3 R) for yuccaol A, yuccaol D and yuccalide A; (2 S ,3 S) for yuccaol B, yuccaol C and yuccaol E; (2 S ,3 S ,2′ S ,3′ S) for gloriosaol A; (2 S ,3 R ,2′ S ,3′ R) for gloriosaol C; (2 S ,3 S ,2′ S ,3′ R) for gloriosaol D; (2 S ,3 R ,2′ S ,3′ S) for gloriosaol E. These findings indicate that the compounds are all biosynthetic derivatives either of (2 R)-naringenin and trans -resveratrol or of trans -3,3 ′ ,5,5 ′ -tetrahydroxy-4′-methoxystilbene. In contrast, gloriosaols are direct derivatives of yuccaols (note that substituting by stilbenoid changes the absolute configuration of C-2 naringenin carbon to 2 S). A putative mechanism for their biosynthesis is proposed taking into account key aspects of regio- and stereoselectivity. Yuccaol B and gloriosaol A showed in vitro moderate inhibitory effects against acetyl-/butyrylcholinesterases (AChE/BChE) with IC 50 values of 43/81 and 45/65 μM respectively. The selectivity index values calculated from the IC 50 values of BChE and AChE were 1.9 and 1.4. Molecular docking simulations showed their interaction with the peripheral anionic site of human AChE and the catalytic site of the human BChE. [Display omitted] • The absolute configurations of spiro-flavostilbenoids from Y. schidigera were elucidated. • Their biosynthetic origin from unusual (2 R)-naringenin was proposed. • Yuccaol B and gloriosaol A showed moderate in vitro AChE/BChE inhibitory activities. • Molecular docking of yuccaol B and gloriosaol A to hAChE/hBChE was performed. [ABSTRACT FROM AUTHOR]

• Synthesis of S-benzyl dithiocarbamates derivatives via a single pot reaction setup. • Characterization of synthesized derivatives via NMR (1H and 13C), FT-IR and high resolution mass spectrometry. • In vitro enzyme inhibition assays against cholinesterase enzyme and monoamine oxidase. • Comprehensive in-silico investigations of synthesized derivatives. The current study was aimed to identify the selective and multi-targeted inhibitors of cholinesterase and monoamine oxidase enzymes. For this purpose, a novel class of multi-targeted compounds i.e., S -benzyl dithiocarbamates (1-30) was synthesized via a single pot reaction and the structures were characterized via NMR (1H and 13C), FT-IR and high-resolution mass spectrometry (HRMS). Moreover, the purity of the final products was determined using thin-layer chromatography (TLC). The compounds were evaluated for their inhibitory potential against cholinesterases (ChE) and monoamine oxidases (MAO). Among all derivatives, compound 5 (2-(trifluoromethyl) benzyl azepane-1-carbodithioate) depicted the maximum inhibition of AChE and BChE enzyme with an IC 50 value of 4.37±0.94 and 14.9±1.11, respectively. The derivative 11, expressed maximum inhibition of MAO-A and MAO-B with an IC 50 value of 1.14±0.03 and 1.01 ± 0.16 µM, respectively. Whereas, compound 16 exhibited maximum inhibitory potential against all four targeted enzymes i.e., AChE, BChE, MAO-A and MAO-B with an IC 50 value of 1.39±0.07 µg/ mL, 1.52±0.14 µg/ mL, 44.9±1.54 µM and 2.85±0.21 µM, respectively. The chemical reactivity profile of the potent derivatives were evaluated through density functional theory studies (DFT) where it was found that compound 5, 6 and 11 possessed reactive character due to narrow LUMO/HOMO energy gap. In addition, Molecular docking studies revealed excellent docking scores and produced sable protein-ligand complexes. The stability of protein-ligand complex was affirmed by molecular dynamic simulations which revealed stable and equilibrated trajectories of simulated complexes. The findings of in-vitro and in-silico studies suggested compound 16 as a promising multi-targeted compound that can be act as lead molecule for the treatment of AD. [Display omitted] [ABSTRACT FROM AUTHOR]

The article highlights study which provided supplementary content in response to some of the researchers' valuable comments, which will aid the understanding. It discusses that the transparent reporting of a multivariable prediction model for individual prognosis of diagnosis (TRIPOD) Statement, providing a detailed framework for reporting prediction models, has guided work.

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase is a key enzyme involved in cholesterol biosynthesis and one of the most important targets for the treatment of hypercholesterolemia. A limited number of studies on the HMG-CoA reductase inhibitory potential of natural products are available. Thus, in the current study, we aimed to test the HMG-CoA reductase inhibitory capacity of extracts from the roots and aerial parts of Salvia multicaulis Vahl., through activity-guided isolation. Our findings revealed that the root extract prepared with dichloromethane–acetone (1:1) showed the highest inhibition (71.97 ± 0.37%) at 100 µg/mL. The extract was then initially fractionated by column chromatography and the obtained fractions were monitored by thin layer chromatography. Fractions which were similar to each other were combined and a total of 15 fractions were obtained. Further conventional chromatographic studies were carried out on the active fractions. Based on these fractions, 10 known compounds, comprising 9 terpenes and 1 steroid derivative in total, were isolated and their structures were verified by a combination of IT-TOF-MS, and 1D and 2D NMR techniques. According to the enzyme inhibition data of the identified compounds, 7-acetoxyhorminone exerted the highest inhibition (84.15 ± 0.10%, IC50 = 63.6 ± 1.21 µg/mL). The molecular docking experiments on 7-acetoxyhorminone and horminone indicated that both compounds strongly bind to the active site of the enzyme. [ABSTRACT FROM AUTHOR]

• Annual phytochemical profile of 5 Origanum species was established. • Cholinesterase inhibition and antioxidant effects of 60 extracts were tested. • The links between the phytochemical fingerprints and activities were revealed. • Aromadendrin showed good correlation with AChE, BChE, and FRAP activities. • Caffeoylarbutin had the lowest binding energy against both enzymes. The ethanol extracts of five Origanum species : O. majorana L., O. onites L., O. syriacum L., O. vulgare subsp. hirtum (Link) Ietsw., and O. vulgare subsp. viride (Boiss.) Hayek, collected annually (each month), were investigated for their cholinesterase inhibition and antioxidant effects. The phytochemical composition of a total of 60 extracts was assessed by HPLC-DAD-ESI/HRMS, revealing the presence of a total of 73 compounds. Possible correlation between the bioactivity and metabolite profiles during 12 months was monitored. Acetylcholinesterase (AChE) inhibitory activity was found to be the highest between April and November (50.29–75.95%, 200 μg/mL), while the highest inhibition towards butyrylcholinesterase (BChE) was observed for the extracts between April and October (71.68–88.97%). Aromadendrin showed good correlation with anti-AChE, anti-BChE and reducing power activities. Furthermore, molecular docking data with aromadendrin, caffeoylarbutin and eriodictyol indicated that caffeoylarbutin had the lowest binding energy against both enzymes. [ABSTRACT FROM AUTHOR]