Ceanothanes Derivatives as Peripheric Anionic Site and Catalytic Active Site Inhibitors of Acetylcholinesterase: Insights for Future Drug Design.

Alzheimer's disease (AD) is a multifactorial and fatal neurodegenerative disorder. Acetylcholinesterase (AChE) plays a key role in the regulation of the cholinergic system and particularly in the formation of amyloid plaques; therefore, the inhibition of AChE has become one of the most promising strategies for the treatment of AD, particularly concerning AChE inhibitors that interact with the peripheral anionic site (PAS). Ceanothic acid isolated from the Chilean Rhamnaceae plants is an inhibitor of AChE through its interaction with PAS. In this study, six ceanothic acid derivatives were prepared, and all showed inhibitory activity against AChE. The structural modifications were performed starting from ceanothic acid by application of simple synthetic routes: esterification, reduction, and oxidation. AChE activity was determined by the Ellmann method for all compounds. Kinetic studies indicated that its inhibition was competitive and reversible. According to the molecular coupling and displacement studies of the propidium iodide test, the inhibitory effect of compounds would be produced by interaction with the PAS of AChE. In silico predictions of physicochemical properties, pharmacokinetics, drug-likeness, and medicinal chemistry friendliness of the ceanothane derivatives were performed using the Swiss ADME tool.

Synthesis and Isolation of Phenol- and Thiol-Derived Epicatechin Adducts Prepared from Avocado Peel Procyanidins Using Centrifugal Partition Chromatography and the Evaluation of Their Antimicrobial and Antioxidant Activity.

Polyphenols from agro-food waste represent a valuable source of bioactive molecules that can be recovered to be used for their functional properties. Another option is to use them as starting material to generate molecules with new and better properties through semi-synthesis. A proanthocyanidin-rich (PACs) extract from avocado peels was used to prepare several semi-synthetic derivatives of epicatechin by acid cleavage in the presence of phenol and thiol nucleophiles. The adducts formed by this reaction were successfully purified using one-step centrifugal partition chromatography (CPC) and identified by chromatographic and spectroscopic methods. The nine derivatives showed a concentration-dependent free radical scavenging activity in the DPPH assay. All compounds were also tested against a panel of pathogenic bacterial strains formed by Listeria monocytogenes (ATCC 7644 and 19115), Staphylococcus aureus (ATCC 9144), Escherichia coli (ATCC 11775 and 25922), and Salmonella enterica (ATCC 13076). In addition, adducts were tested against two no-pathogenic strains, Limosilactobacillus fermentum UCO-979C and Lacticaseibacillus rhamnosus UCO-25A. Overall, thiol-derived adducts displayed antimicrobial properties and, in some specific cases, inhibited biofilm formation, particularly in Listeria monocytogenes (ATCC 7644). Interestingly, phenolic adducts were inactive against all the strains and could not inhibit its biofilm formation. Moreover, depending on the structure, in specific cases, biofilm formation was strongly promoted. These findings contribute to demonstrating that CPC is a powerful tool to isolate new semi-synthetic molecules using avocado peels as starting material for PACc extraction. These compounds represent new lead molecules with antioxidant and antimicrobial activity.

Lipotoxicity, glucotoxicity and some strategies to protect vascular smooth muscle cell against proliferative phenotype in metabolic syndrome.

Metabolic syndrome (MetS) is a risk factor for the development of cardiovascular disease (CVD) and atherosclerosis through a mechanism that involves vascular smooth muscle cell (VSMC) proliferation, lipotoxicity and glucotoxicity. Several molecules found to be increased in MetS, including free fatty acids, fatty acid binding protein 4, leptin, resistin, oxidized lipoprotein particles, and advanced glycation end products, influence VSMC proliferation. Most of these molecules act through their receptors on VSMCs by activating several signaling pathways associated with ROS generation in various cellular compartments. ROS from NADPH-oxidase and mitochondria have been found to promote VSMC proliferation and cell cycle progression. In addition, most of the natural or synthetic substances described in this review, including pharmaceuticals with hypoglycemic and hypolipidemic properties, attenuate VSMC proliferation by their simultaneous modulation of cell signaling and their scavenging property due to the presence of a phenolic ring in their structure. This review discusses recent data in the literature on the role that several MetS-related molecules and ROS play in the change from contractile to proliferative phenotype of VSMCs. Hence the importance of proposing an appropriate strategy to prevent uncontrolled VSMC proliferation using antioxidants, hypoglycemic and hypolipidemic agents.

Cyclopeptide Alkaloids from Discaria chacaye (Rhamnaceae) as Result of Symbiosis with Frankia (Actinomycetales).

Cyclopeptide alkaloids with different biological activities are present in plants of the family Rhamnaceae. Plants of this family grow in a symbiotic relationship with aerobic Gram-positive actinomycetes belonging to the genus Frankia. This goal of this research was a study of the comparative profile of alkaloids present in Discaria chacaye and to establish a connection between the presence or absence of Frankia sp. and the alkaloids. In addition, insecticidal activities of the alkaloidal extract were examined. A total of 24 alkaloids were identified, of which 12 have a benzylisoquinoline skeleton, 9 were cyclopeptides, 2 isoquinolines, and 1 aporphine. The presence of cyclopeptide alkaloids is associated with Frankia nodules in the plant root. The alkaloid extracts showed insecticidal activity with mortality dose-dependence and LD50 values between 44 to 71 µg/mL.

Assessments of Ceanothanes Triterpenes as Cholinesterase Inhibitors: An Investigation of Potential Agents with Novel Inspiration for Drug Treatment of Neurodegenerative Diseases.

The purpose of this study was to determine the inhibitory capacity of ceanothanes triterpenes isolate from Chilean Rhamnaceae on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Seven ceanothanes triterpenes were isolated from aerial parts of plant material by classical phytochemical methods or prepared by the hemisynthetic method. Structures were determined by the spectroscopic method (1H-NMR and 13C NMR) and mass spectrometry (MS). AChE and BChE activity were determined by the Ellmann method for all compounds. All tested compounds exerted a greater affinity to AChE than to BChE, where compound 3 has an IC50 of 0.126 uM for AChE and of >500 uM to BChE. Kinetic studies indicated that its inhibition was competitive and reversible. According to the molecular coupling and displacement studies of the propidium iodide test, the inhibitory effect of compound 3 would be produced by interaction with the peripheral anionic site (PAS) of AChE. The compounds tested (1−7) showed an important inhibitory activity of AChE, binding to PAS. Therefore, inhibitors that bind to PAS would prevent the formation of the AChE-Aß complex, constituting a new alternative in the treatment of Alzheimer's disease (AD).

Dyhidro-ß-agarofurans natural and synthetic as acetylcholinesterase and COX inhibitors: interaction with the peripheral anionic site (AChE-PAS), and anti-inflammatory potentials.

In order to find molecules of natural origin with potential biological activities, we isolate and synthesise compounds with agarofuran skeletons (epoxyeudesmanes). From the seeds of Maytenus disticha and Maytenus magellanica we obtained six dihydro-ß-agarofurans, and by means of the Robinson annulation reaction we synthesised five compounds with the same skeleton. The structures were established on the basis of NMR, IR, and MS. The evaluated compounds showed inhibitory activity on the acetylcholinesterase enzyme and on the COX enzymes. Compound 4 emerged as the most potent in the acetylcholinesterase inhibition assay with IC50 17.0 ± 0.016 µM on acetylcholinesterase (AChE). The compounds evaluated were shown to be selective for AChE. The molecular docking, and the propidium displacement assay suggested that the compounds do not bind to the active site of the enzyme AChE, but rather bind to the peripheral anionic site (PAS) of the enzyme, on the other hand, the natural compound 8, showed the best inhibitory activity on the COX-2 enzyme with an IC50 value of 0.04 ± 0.007 µM. The pharmacokinetic profile calculated in silico using the SWISSADME platform shows that these molecules could be considered as potential drugs for the treatment of neurodegenerative diseases such as AD.

In vitro gastric bioaccessibility of avocado peel extract in beef and soy-based burgers and its impact on Helicobacter pylori risk factors.

The objective of the present study was to investigate the impact of phenolic-rich avocado peel extract (APE) as an ingredient in beef and soy-based burgers to increase their antioxidant activity, reduce lipid and protein oxidation during gastric digestion, and inhibit urease and anhydrase carbonic activity, which are considered as key factors in the main steps of Helicobacter pylori adhesion in the stomach. The gastric bioaccessible fraction of soy and beef burgers with added 0.5% APE obtained by in vitro digestion exhibited a higher content of phenolic compounds, including monomeric and oligomeric (epi)catechin forms and quercetin, and reduced levels of thiobarbituric acid-reactive substances (TBARS) and carbonyls (49% to 73% and 57% to 60%, respectively) when compared with control burgers. Moreover, the burgers with APE inhibited urease and carbonic anhydrase activity. Results generally showed that including APE reduces the primary risk factors associated with H. pylori infection.

Incorporation of avocado peel extract to reduce cooking-induced hazards in beef and soy burgers: A clean label ingredient.

In this study, the benefits of using avocado peel extract (APE), rich in phenolic compounds, to reduce the oxidation and formation of harmful compounds resulting from cooking, were investigated. Beef and soy-based burgers with the addition of APE (0.5% and 1%) were studied after pan frying concerning proximate and physicochemical characteristics, inhibition of protein and lipid oxidation products (thiobarbituric acid reactive substances [TBARS], hexanal, and carbonyls), heterocyclic aromatic amines (HAs) and acrylamide formation. Sensory analysis was additionally performed. APE-affected proximate composition, protein, fat, and ash contents (%) were found to be markedly higher in APE-incorporated burgers (~28.32 ± 0.29, ~14.00 ± 0.01, and ~1.57 ± 0.05, respectively), compared with the controls (~26.55 ± 0.51, ~12.77 ± 0.32, and ~1.48 ± 0.16, respectively). Lower concentrations of TBARS, hexanal, and carbonyls were observed in APE-treated burgers on Days 1 and 10, post-cooking, compared to controls. Overall, it was found that APE had a greater protective effect than the positive control (sodium ascorbate incorporated) in beef burgers. In soy burgers, the positive control demonstrated pro-oxidant activity. The addition of 0.5% APE was found to inhibit HAs and acrylamide formation in beef and soy burgers. Although the addition of APE affected the color of both meat and soy burgers, it did not impact consumer preference. It was therefore concluded that APE extract might be a suitable clean-label alternative to synthetic antioxidants, and that it can protect and increase the nutritional value of meat and meat-free burgers.

Polyphenolic Compounds Extracted and Purified from Buddleja Globosa Hope (Buddlejaceae) Leaves Using Natural Deep Eutectic Solvents and Centrifugal Partition Chromatography.

Chemical profiling of Buddleja globosa was performed by high-performance liquid chromatography coupled to electrospray ionization (HPLC-DAD-ESI-IT/MS) and quadrupole time-of-flight high-resolution mass spectrometry (HPLC-ESI-QTOF/MS). The identification of 17 main phenolic compounds in B. globosa leaf extracts was achieved. Along with caffeoyl glucoside isomers, caffeoylshikimic acid and several verbascoside derivatives (ß-hydroxyverbascoside and ß-hydroxyisoverbascoside) were identified. Among flavonoid compounds, the presence of 6-hydroxyluteolin-7-O-glucoside, quercetin-3-O-glucoside, luteolin 7-O-glucoside, apigenin 7-O-glucoside was confirmed. Campneoside I, forsythoside B, lipedoside A and forsythoside A were identified along with verbascoside, isoverbascoside, eukovoside and martynoside. The isolation of two bioactive phenolic compounds verbascoside and forsythoside B from Buddleja globosa (Buddlejaceae) was successfully achieved by centrifugal partition chromatography (CPC). Both compounds were obtained in one-step using optimized CPC methodology with the two-phase solvent system comprising ethyl acetate-n-butanol-ethanol-water (0.25:0.75:0.1:1, v/v). Additionally, eight Natural Deep Eutectic Solvents (NADESs) were tested for the extraction of polyphenols and compared with 80% methanol. The contents of verbascoside and luteolin 7-O-glucoside after extraction with 80% methanol were 26.165 and 3.206 mg/g, respectively. Among the NADESs tested in this study, proline- citric acid (1:1) and choline chloride-1, 2- propanediol (1:2) were the most promising solvents. With these NADES, extraction yields for verbascoside and luteolin 7-O-glucoside were 51.045 and 4.387 mg/g, respectively. Taken together, the results of this study confirm that CPC enabled the fast isolation of bioactive polyphenols from B. globosa. NADESs displayed higher extraction efficiency of phenolic and therefore could be used as an ecofriendly alternative to classic organic solvents.

Western Dietary Pattern Antioxidant Intakes and Oxidative Stress: Importance During the SARS-CoV-2/COVID-19 Pandemic.

The importance of balanced dietary habits, which include appropriate amounts of antioxidants to maintain the immune system, has become increasingly relevant during the current SARS-CoV-2/COVID-19 pandemic, because viral infections are characterized by high oxidative stress. Furthermore, the measures taken by governments to control the pandemic have led to increased anxiety, stress, and depression, which affect physical and mental health, all of which are influenced by nutritional status, diet, and lifestyle. The Mediterranean diet (MD), Atlantic diet (AD), and the Dietary Guidelines for Americans all provide the essential vitamins, minerals, and phenolic compounds needed to activate enzymatic and nonenzymatic antioxidant responses. However, viral pandemics such as the current COVID-19 crisis entail high oxidative damage caused by both the infection and the resultant social stresses within populations, which increases the probability and severity of infection. Balanced dietary patterns such as the MD and the AD are characterized by the consumption of fruit, vegetables, legumes, olive oil, and whole grains with low intakes of processed foods and red meat. For a healthy lifestyle in young adults, the MD in particular provides the required amount of antioxidants per day for vitamins D (0.3-3.8 µg), E (17.0 mg), C (137.2-269.8 mg), A (1273.3 µg), B-12 (1.5-2.0 µg), and folate (455.1-561.3 µg), the minerals Se (120.0 µg), Zn (11.0 mg), Fe (15.0-18.8 mg), and Mn (5.2-12.5 mg), and polyphenols (1171.00 mg) needed to maintain an active immune response. However, all of these diets are deficient in the recommended amount of vitamin D (20 µg/d). Therefore, vulnerable populations such as elders and obese individuals could benefit from antioxidant supplementation to improve their antioxidant response. Although evidence remains scarce, there is some indication that a healthy diet, along with supplemental antioxidant intake, is beneficial to COVID-19 patients.

Assessment of Insecticidal Activity of Benzylisoquinoline Alkaloids from Chilean Rhamnaceae Plants against Fruit-Fly Drosophila melanogaster and the Lepidopteran Crop Pest Cydia pomonella.

The Chilean plants Discaria chacaye, Talguenea quinquenervia (Rhamnaceae), Peumus boldus (Monimiaceae), and Cryptocarya alba (Lauraceae) were evaluated against Codling moth: Cydia pomonella L. (Lepidoptera: Tortricidae) and fruit fly Drosophila melanogaster (Diptera: Drosophilidae), which is one of the most widespread and destructive primary pests of Prunus (plums, cherries, peaches, nectarines, apricots, almonds), pear, walnuts, and chestnuts, among other. Four benzylisoquinoline alkaloids (coclaurine, laurolitsine, boldine, and pukateine) were isolated from the above mentioned plant species and evaluated regarding their insecticidal activity against the codling moth and fruit fly. The results showed that these alkaloids possess acute and chronic insecticidal effects. The most relevant effect was observed at 10 µg/mL against D. melanogaster and at 50 µg/mL against C. pomonella, being the alteration of the feeding, deformations, failure in the displacement of the larvae in the feeding medium of D. melanogaster, and mortality visible effects. In addition, the docking results show that these type of alkaloids present a good interaction with octopamine and ecdysone receptor showing a possible action mechanism.

Isolation of Three Lycorine Type Alkaloids from Rhodolirium speciosum (Herb.) Ravenna Using pH-Zone-Refinement Centrifugal Partition Chromatography and Their Acetylcholinesterase Inhibitory Activities.

Preparative separation of three lycorine type alkaloids from Rhodolirum speciosum (Amaryllidaceae) was successfully carried out using pH-zone-refinement centrifugal partition chromatography (CPC) using the solvent system methyl-tert-butyl ether/acetonitrile/water (4:1:5, v/v/v) in descending mode. Using this system, Alkaloid 1 (165.7 mg, 88.2%, purity), 2 (60.1 mg, 97.7% purity) and 3 (12.3 mg, 84.4% purity) were obtained in one step. For structure elucidation, the pure alkaloids were subjected to spectroscopy analysis using nuclear magnetic resonance experiments (1H-NMR, 13C-NMR) and gas chromatography coupled with mass spectrometry (GC-MS). Alkaloids 1, 2, and 3 were identified as 1-O-acetyl-5,6-dehydrolycorine, 1-O-acetyl-lycorine, and 1,2-O-diacetyl-5,6-dehydrolycorine, respectively. The acetylcholinesterase inhibitory activity of these alkaloids was IC50 151.1 µg/mL, IC50 203.5 µg/mL, IC50 470.0 µg/mL, and IC50 17.1 µg/mL, respectively.

Fractionation and Hydrolyzation of Avocado Peel Extract: Improvement of Antibacterial Activity.

Avocado Hass (Persea americana Mill) peel extract (APE) has the potential as a natural ingredient to substitute for chemical preservatives. The objectives of this study were to assess the phytochemical composition by high-performance liquid chromatography-quadrupole time-of-flight mass/mass spectrometry (HPLC-qTOF-MS/MS), total phenolic content (TPC), proanthocyanidin (PAC) content, and antioxidant activity of the APE, the organic fraction (OF), the aqueous fraction (AF), and the acid-microwave hydrolyzed APE (HAPE), on the antibacterial activity (ABA). The results indicated that APE and OF contained (p ˂ 0.05) a higher phenolic composition and antioxidant activity than AF and HAPE. The ABA specified that Pseudomonas aeruginosa and Bacillus cereus were inhibited by all the extracts (minimal inhibitory concentration-MIC ≥ 500 µg/mL), Staphylococcus aureus was only significantly inhibited by APE (≥750 µg/mL), the same MIC was observed for the OF on Salmonella spp. and Listeria monocytogenes. The HAPE increased the inhibitory efficiency up to 25% on Escherichia coli and Salmonella spp. (MIC ≥ 750 µg/mL), and 83.34% on L. monocytogenes (MIC ≥ 125 µg/mL) compared to APE (MIC ≥ 750 µg/mL). Also, HAPE inhibited the biofilm formation at the lowest concentration (125 µg/mL); meanwhile, the biofilm disruption showed to be concentration-time-dependent (p ˃ 0.05) compared to amoxicillin. In conclusion, the fractionation and hydrolyzation of APE improved the ABA; thus, those strategies are useful to design new antimicrobial compounds.

In vitro micropropagation and alkaloids analysis by GC-MS of Chilean Amaryllidaceae plants: Rhodophiala pratensis.

INTRODUCTION: Plants from Amaryllidaceae family are of interest since they produce a particular type of alkaloid useful for the treatment of neurodegenerative diseases of the central nervous system, such as Galanthamine. Given the low content of these secondary metabolites in the plant, it is necessary to study mechanisms to increase the productivity of them. OBJECTIVE: To obtain fast qualitative and quantitative analysis of the alkaloids and extend the understanding of biosynthesis and metabolism in these kinds of plants. Furthermore, establish a reliable, simple and fast analytical method for the in vitro callus culture of vegetative organs for Rhodophiala pratensis species. METHODS: The alkaloids composition of the callus culture of R. pratensis were analysed by gas chromatography coupled with mass spectrometry (GC-MS). RESULTS: A methodology for the qualitative and quantitative analysis of the alkaloids present in fresh callus culture of this wild plant species was established. The analysis showed alternation in the alkaloids type ratio and number of compounds between wild bulbs, in vitro bulbs and callus. It was possible to identify 24 alkaloids from a pool of 60 signals whose fragmentation pattern corresponds to the alkaloids of Amaryllidaceae plants. Together with the aforementioned, the amount and type of alkaloid present in the plant material obtained by in vitro culture of R. pratensis was determined in the same way. The results show the high biosynthetic potential of in vitro grown bulbs and callus tissue that are able to produce significant amounts of pharmacologically relevant alkaloids from R. pratensis in various proportions that depend on the culture conditions such as supplementation with growth substances. The in vitro grown bulbs produce an alkaloidal extract that contain a 52.6% w/w of alkaloids. CONCLUSION: This study allowed the alkaloid content in callus culture of R. pratensis to be found by means of GC-MS. These results allowed a relationship between the type of growth regulator and the type of alkaloids found to be established. Finally, we can say that the results achieved to state that the production of alkaloids using different combinations of growth regulators could be directed during in vitro micropropagation from provided plant material.

Neuroprotective activity of isoquinoline alkaloids from of Chilean Amaryllidaceae plants against oxidative stress-induced cytotoxicity on human neuroblastoma SH-SY5Y cells and mouse hippocampal slice culture.

In this study we evaluate the chemical composition and neuroprotective effects of alkaloid fractions of the Amaryllidaceae species Rhodophiala pratensis, Rhodolirium speciosum, Phycella australis and Phaedranassa lehmannii. Gas chromatography-mass spectrometry (GC/MS) enable the identification of 41 known alkaloids. Rhodolirium speciosum and Rhodophiala pratensis were the most active extracts against acetylcholinesterase (AChE), with IC50 values of 35.22 and 38.13 µg/mL, respectively. The protective effect of these extracts on human neuroblastoma cells (SH-SY5Y) subjected to mitochondrial oxidative stress with rotenone/oligomycin A (R/O) and toxicity promoted by okadaic acid (OA) was evaluated. Only Phycella australis and Rhodophiala pratensis at 0.75 and 1.5 µg/mL, tend to reverse the cell death induced by R/O by around 12%. In OA assay, alkaloid fractions of Phycella Australis and Phaedranassa lehmannii displayed a concentration-dependent (0.375-3.0 µg/mL) effect with a maximum neuroprotective response of 78% and 84%, respectively. Afterwards, neuroprotective effects of Phycella australis (3 and 6 µg/mL) in mouse hippocampal slices stressed with oxygen glucose deprivation/reoxygenation (OGD/R), shown a protection greater than 14%. Finally, Phycella Australis (6 µg/mL) reverted the cell viability from 65% to 90% in slices treated with OA, representing a protection of 25% attributable to the alkaloids of this species.

Identification of structurally diverse alkaloids in Talguenea quinquinervia (gill. Et hook) by liquid chromatography/electrospray ionisation tandem mass spectroscopy and insecticidal activity.

INTRODUCTION: Talguenea quinquinervia has been used in folk medicine and to dye wool, and the main constituents are alkaloids and triterpenes. Identification of these type of compounds in this specie is a necessary step to understand the biological properties. OBJECTIVE: To evaluate the relationship between the chemical composition of root from T. quinquinervia and its insecticidal properties using liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS). METHODS: Alkaloids were extracted using Soxhlet extraction with methanol. Total extract was partitioned at pH 2 and 12 to enrich alkaloid constituents and to remove interferences. The separation of alkaloids in the Talguenea extract was performed on a C18 column using gradient elution and their tandem mass spectra were obtained by quadrupole time-of-flight tandem mass spectrometry (QTOF-MS/MS) to perform accurate mass measurements of fragment ions for the alkaloid constituents. RESULTS: Several types of alkaloids were separated and identified by LC-ESI-MS/MS. The structural assignment of individual alkaloids was performed based on convergence of MS/MS spectral data, pH partitioning behaviour, LC retention behaviour, and accurate mass measurements. The pH partition of the extract provided structural information about unknown alkaloids extracted from T. quinquinervia. A total of 20 compounds were identified and tentatively characterised, and of these 15 alkaloids were reported for the first time in the investigated T. quinquinervia. CONCLUSION: The chemical profiling of alkaloids in T. quinquinervia with different origins was performed for the first time and provided diagnostic ions for diverse alkaloids in T. quinquinervia. Insecticidal activity observed can be explain by the presence of alkaloid and pentacyclic triterpenes on the fractions assayed.

Phytochemical Composition and Biological Activities of Dyssodia tagetiflora Lag.

While plants of the genus Dyssodia are used by man to a certain extent, few phytochemical and pharmacological studies have been performed with species of this genus. D. tagetiflora is an endemic plant of Mexico and has been used as fodder. The aim of this research was to isolate and identify the main bioactive components and evaluate the insecticidal, antioxidant, genotoxic and cytoprotective activities of D. tagetiflora. The isolated substances included an essential oil composed of six monoterpenes, and extracts containing two flavonols, three flavonol-glycosides and four thiophenes. The compounds were characterized using spectroscopic and spectrometric methods, including GC/MS, MS and NMR. The essential oil showed insecticidal activity against Drosophila melanogaster larvae. The methanolic extract of D. tagetiflora (DTME) had strong antioxidant activity against DPPH and ABTS radicals; DTME showed no evidence of genotoxic or cytotoxic effects. In contrast, DTME showed a cytoprotective effect attenuating the formation of H2 O2 -induced micronuclei in Vicia faba roots. This report is the first to describe the phytochemical and biological activity of D. tagetiflora.

Toxicity of coumarins synthesized by Pechmann-Duisberg condensation against Drosophila melanogaster larvae and antibacterial effects.

On the background of the search of new insecticides friendly with the environment for replace those from synthesis organic origin with adverse effects on animals, soils and vegetables. It is reported in this study, the synthesis of a series of coumarins derivatives synthesized by Pechmann-Duisberg condensation assisted by microwave irradiation, their antibacterial and insecticidal activities. The most relevant results show that all compounds exhibit a mortality effect of 30-80% with doses between 10 and 100 µg/mL. This activity is related to alkyl or aryl substituent type at position C-4 coumarin skeleton. The coumarins 5, 6, 7 and 9 showed highest insecticidal activities, and these coumarins have at 4-position a bulky and low polarity substituent. The aim of this work is to find the effects of the 4-substitued coumarins with different lipophilic and bulky substituents. Even though many researchers were worked on coumarins, there are not reports about the insecticidal effects of specifically 4-substitued coumarins. The difference of our major findings versus current knowledge is in this scope of the research. On the other hand, was possible to find that a chloride at 4-position, drew to extend the antibacterial spectra.

Bauhinia candicans improves the endothelium-dependent relaxation in aortic rings of alloxan-diabetic Rats / Bauhinia candicans mejora la relajación dependiente de endotelio en anillos de ratas diabético-aloxánicas

Bahuinia candicans is a plant used in Chile for diabetes management. The aim of the present study was to investigate the relaxing responsiveness to acetylcholine (Ach) of phenylephrine-precontracted aortic rings from alloxan-diabetic rats treated with an aqueous-ethanol extract of B.candicans leaves (EBc-rats, 120 mg/kg/day). EBc significantly reduced fasting blood sugar from 292.4 +/- 9.2 mg/dl to 174.6 +/- 12.8 mg/dl. Ach induced a negligible reduction of tension (28 +/- 6 percent) of aortic rings from ALX-rats compared with EBc-rats (48 +/- 5.5 percent) and normal (57 +/- 5 percent). The enhanced sensitivity to phenylephrine in aortic rings from diabetic rats was reduced in EBc-rats. Removal of the endothelium or pretreatment of rings of EBc-rats with nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) increased the Phe response. The nitric oxide (NO) donor sodium nitroprusside (SNP) induced a normal relaxation in these rings. The results suggest that the extract of leaves of B. candicans increases endothelium-dependent relaxation of aortic rings of ALX-rats and its use may be helpful in the prevention of diabetic complications.

Bahuinia candicans es una planta usada en Chile para el tratamiento de la diabetes mellitus.. Se investigó el efecto de un extracto acuo-etanólico de las hojas de Bauhinia candicans (EBc, 120 mg/kg/día) sobre la respuesta relajadora de acetilcolina en anillos aórticos de ratas diabético-aloxánicas precontraídos con fenilefrina. EBc redujo la glicemia de ayuno de 292.4 +/- 9.2 mg/dl a 174.6 +/- 12.8 mg/dl. Acetilcolina indujo una pequeña relajación (28 +/- 6 por ciento) de los anillos de ratas diabéticas comparadas con los de ratas tratadas con EBc (ratas-EBc; 48 +/- 5.5 por ciento) y con los de ratas normales (57 +/- 5 por ciento). La alta sensibilidad a Phe en aorta de ratas diabéticas fue reducida en ratas-EBc. La remoción del endotelio y la incubación con L-NAME de los anillos de ratas-EBc generaron una alta respuesta a Phe. Nitroprusiato de sodio (SNP) indujo una relajación normal en estos anillos. Los resultados sugieren que el extracto de hojas de B. candicans aumenta la relajación dependiente de endotelio de los anillos de aorta de ratas diabéticas y su uso puede ser útil en la prevención de las complicaciones de la diabetes.