In Vitro and Molecular Docking Evaluation of the Anticholinesterase and Antidiabetic Effects of Compounds from Terminalia macroptera Guill. & Perr. (Combretaceae).

Alzheimer's disease (AD) and diabetes are non-communicable diseases with global impacts. Inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are suitable therapies for AD, while α-amylase and α-glucosidase inhibitors are employed as antidiabetic agents. Compounds were isolated from the medicinal plant Terminalia macroptera and evaluated for their AChE, BChE, α-amylase, and α-glucosidase inhibitions. From 1H and 13C NMR data, the compounds were identified as 3,3'-di-O-methyl ellagic acid (1), 3,3',4'-tri-O-methyl ellagic acid-4-O-ß-D-xylopyranoside (2), 3,3',4'-tri-O-methyl ellagic acid-4-O-ß-D-glucopyranoside (3), 3,3'-di-O-methyl ellagic acid-4-O-ß-D-glucopyranoside (4), myricetin-3-O-rhamnoside (5), shikimic acid (6), arjungenin (7), terminolic acid (8), 24-deoxysericoside (9), arjunglucoside I (10), and chebuloside II (11). The derivatives of ellagic acid (1-4) showed moderate to good inhibition of cholinesterases, with the most potent being 3,3'-di-O-methyl ellagic acid, with IC50 values of 46.77 ± 0.90 µg/mL and 50.48 ± 1.10 µg/mL against AChE and BChE, respectively. The compounds exhibited potential inhibition of α-amylase and α-glucosidase, especially the phenolic compounds (1-5). Myricetin-3-O-rhamnoside had the highest α-amylase inhibition with an IC50 value of 65.17 ± 0.43 µg/mL compared to acarbose with an IC50 value of 32.25 ± 0.36 µg/mL. Two compounds, 3,3'-di-O-methyl ellagic acid (IC50 = 74.18 ± 0.29 µg/mL) and myricetin-3-O-rhamnoside (IC50 = 69.02 ± 0.65 µg/mL), were more active than the standard acarbose (IC50 = 87.70 ± 0.68 µg/mL) in the α-glucosidase assay. For α-glucosidase and α-amylase, the molecular docking results for 1-11 reveal that these compounds may fit well into the binding sites of the target enzymes, establishing stable complexes with negative binding energies in the range of -4.03 to -10.20 kcalmol-1. Though not all the compounds showed binding affinities with cholinesterases, some had negative binding energies, indicating that the inhibition was thermodynamically favorable.

Bridging the Chemical Profile and Biological Activities of a New Variety of Agastache foeniculum (Pursh) Kuntze Extracts and Essential Oil.

This study investigated the phytochemical content of alcoholic extracts and essential oil of a new variety of medicinal plants, Agastache foeniculum (Pursh), which Kuntze adapted for cultivation in Romania, namely "Aromat de Buzau". The essential oil was investigated by GC-MS, while the identification and quantification of various compounds from alcoholic extracts were performed by HPLC-DAD. The total phenol and flavonoid contents of the extracts were evaluated by using standard phytochemical methods. The antioxidant activities of ethanol, methanol extracts, and essential oil of the plant were also assessed against 2,2'-diphenyl-1-picrylhydrazyl (DPPH•), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), and by ferric reducing power (FRAP) using spectroscopic methods. Cyclic voltammetry was used to evaluate the antioxidant capacity of the essential oil. The concentrations of phenolic compounds were higher in methanolic extract compared to ethanolic extract. A significant correlation was found between total phenol and total flavonoid contents (r = 0.9087). Significant high correlations were also found between the total phenolic compounds and the antioxidant activities of the extracts (r ≥ 0.8600, p < 0.05). In addition, the extracts and essential oil showed good antioxidant and xanthine oxidase inhibitory activities. Estragole was detected as the major constituent of the essential oil (94.89%). The cytotoxic activity of the essential oil was evaluated by the MTT assay. At lower concentrations (1 µg/mL) high cytotoxicity against MCF-7 breast cancer cells was observed but not on the non-tumoral dermal fibroblasts (HDF) which indicated selectivity for cancer cells and suggests the presence of biologically active components that contribute to the observed high cytotoxic effect. Findings from the present study offer new perspectives on the use of A. foeniculum as a potential source of bioactive compounds and a good candidate for pharmaceutical plant-based products.

In Vitro and In Silico Evaluation of Anticholinesterase and Antidiabetic Effects of Furanolabdanes and Other Constituents from Graptophyllum pictum (Linn.) Griffith.

Graptophyllum pictum is a tropical plant noticeable for its variegated leaves and exploited for various medicinal purposes. In this study, seven compounds, including three furanolabdane diterpenoids, i.e., Hypopurin E, Hypopurin A and Hypopurin B, as well as with Lupeol, ß-sitosterol 3-O-ß-d-glucopyranoside, stigmasterol 3-O-ß-d-glucopyranoside and a mixture of ß-sitosterol and stigmasterol, were isolated from G. pictum, and their structures were deduced from ESI-TOF-MS, HR-ESI-TOF-MS, 1D and 2D NMR experiments. The compounds were evaluated for their anticholinesterase activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BchE), as well as their antidiabetic potential through inhibition of α-glucosidase and α-amylase. For AChE inhibition, no sample had IC50 within tested concentrations, though the most potent was Hypopurin A, which had a percentage inhibition of 40.18 ± 0.75%, compared to 85.91 ± 0.58% for galantamine, at 100 µg/mL. BChE was more susceptible to the leaves extract (IC50 = 58.21 ± 0.65 µg/mL), stem extract (IC50 = 67.05 ± 0.82 µg/mL), Hypopurin A (IC50 = 58.00 ± 0.90 µg/mL), Hypopurin B (IC50 = 67.05 ± 0.92 µg/mL) and Hypopurin E (IC50 = 86.90 ± 0.76 µg/mL). In the antidiabetic assay, the furanolabdane diterpenoids, lupeol and the extracts had moderate to good activities. Against α-glucosidase, lupeol, Hypopurin E, Hypopurin A and Hypopurin B had appreciable activities but the leaves (IC50 = 48.90 ± 0.17 µg/mL) and stem (IC50 = 45.61 ± 0.56 µg/mL) extracts were more active than the pure compounds. In the α-amylase assay, stem extract (IC50 = 64.47 ± 0.78 µg/mL), Hypopurin A (IC50 = 60.68 ± 0.55 µg/mL) and Hypopurin B (IC50 = 69.51 ± 1.30 µg/mL) had moderate activities compared to the standard acarbose (IC50 = 32.25 ± 0.36 µg/mL). Molecular docking was performed to determine the binding modes and free binding energies of Hypopurin E, Hypopurin A and Hypopurin B in relation to the enzymes and decipher the structure-activity relationship. The results indicated that G. pictum and its compounds could, in general, be used in the development of therapies for Alzheimer's disease and diabetes.

Antibiofilm and Anti-Quorum Sensing Potential of Cycloartane-Type Triterpene Acids from Cameroonian Grassland Propolis: Phenolic Profile and Antioxidant Activity of Crude Extract.

Propolis is very popular for its beneficial health properties, such as antimicrobial activity and antioxidant effects. It is one of the most long-serving traditional medicines to mankind due to its interesting chemical diversity and therapeutic properties. The detailed chemical information of propolis samples is very necessary to guarantee its safety and for it to be accepted into health care systems. The phenolic profile of the hydroethanolic extract was determined using HPLC-DAD, and the antioxidant was evaluated using five complementary methods. Triterpenoids were isolated using column chromatography and characterized using 1H NMR and 13C NMR. The effects of the extract and the isolated compounds on quorum sensing mediated processes and biofilm formation in bacteria were evaluated. Protocatechic acid (40.76 ± 0.82 µg/g), 4-hydroxybenzoic acid (24.04 ± 0.21 µg/g), vanillic acid (29.90 ± 1.05 µg/g), quercetin (43.53 ± 1.10 µg/g), and luteolin (4.44 ± 0.48 µg/g) were identified and quantified. The extract showed good antioxidant activity in the DPPH•, ABTS•+, CUPRAC, and metal chelating assays, and this antioxidant effect was confirmed by cyclic voltammetry. 27-Hydroxymangiferonic acid (1), Ambolic acid (2), and Mangiferonic acid (3) were isolated from anti-quorum sensing activity at MIC, and it was indicated that the most active sample was the extract with inhibition diameter zone of 18.0 ± 1.0 mm, while compounds 1, 2, and 3 had inhibition zones of 12.0 ± 0.5 mm, 9.0 ± 1.0 mm, and 12.3 ± 1.0 mm, respectively. The samples inhibited the P. aeruginosa PA01 swarming motility at the three tested concentrations (50, 75, and 100 µg/mL) in a dose-dependent manner. The propolis extract was able to inhibit biofilm formation by S. aureus, E. coli, P. aeruginosa, C. albicans, and C. tropicalis at MIC concentration. Compound 1 proved biofilm inhibition on S. aureus, L. monocytogenes, E. faecalis, E. coli, and C. tropicalis at MIC and MIC/2; compound 2 inhibited the formation of biofilm at MIC on S. aureus, E. faecalis, E. coli, S. typhi, C. albicans, and C. tropicalis; and compound 3 inhibited biofilm formation on E. faecalis, E. coli, C. albicans, and C. tropicalis and further biofilm inhibition on E. coli at MIC/4 and MIC/8. The studied propolis sample showed important amounts of cycloartane-type triterpene acids, and this indicates that there can be significant intra-regional variation probably due to specific flora within the vicinity. The results indicate that propolis and its compounds can reduce virulence factors of pathogenic bacteria.

Characterizations of Six Pomegranate (Punica granatum L.) Varieties of Global Commercial Interest in Morocco: Pomological, Organoleptic, Chemical and Biochemical Studies.

Pomegranate variety properties are important not only to demonstrate their diversity but also to satisfy the current market need for high-quality fruits. This study aims to characterize pomological and physico-chemical features as well as the antioxidant capacity of Moroccan local cultivars (Djeibi, Mersi, Sefri 1 and Sefri 2) compared to the imported ones (Mollar de Elche and Hicaz). The pomological characteristics of varieties were relatively diverse. The juice varieties (PJ) displayed a marketed variability in organoleptic and quality properties, such as the flavor, juice yield, and micro/macronutrients contents. Interrelationships among the analyzed properties and PJ varieties were investigated by principal component analysis (PCA). Dimension of the data set was reduced to two components by PCA accounting for 64.53% of the variability observed. The rinds varieties (PR) were studied for their total phenolics, flavonoids, and condensed tannins quantifications. PR varieties extracts exhibited different levels of free radical scavenging activity and local varieties revealed a greater potential with stability over time. The HPLC-DAD analyses of PR extracts revealed (+) catechin as the major compound, where the highest content was found for the local varieties. The SEC analysis showed the molecular weight distribution of phenolic compounds with a high size of condensed tannins formed by the polymerization of the catechin monomer. Given these properties, this research provides an easy selection of high-quality fruits as potential candidates for local market needs.

In Vitro Evaluation of α-amylase and α-glucosidase Inhibition of 2,3-Epoxyprocyanidin C1 and Other Constituents from Pterocarpus erinaceus Poir.

Diabetes mellitus is a metabolic disorder which is one of the leading causes of mortality and morbidities in elderly humans. Chronic diabetes can lead to kidney failure, blindness, limb amputation, heart attack and stroke. Physical activity, healthy diets and medications can reduce the incidence of diabetes, so the search for more efficient antidiabetic therapies, most especially from natural products, is a necessity. Herein, extract from roots of the medicinal plant Pterocarpus erinaceus was purified by column chromatography and afforded ten compounds which were characterized by EIMS, HR-FAB-MS, 1D and 2D NMR techniques. Amongst them were, a new trimeric derivative of epicatechin, named 2,3-Epoxyprocyanidin C1 (1); two pentacyclic triterpenoids, friedelin (2) and betulin (3); angolensin (4); flavonoids such as 7-methoxygenistein (5), 7-methoxydaidzein (6), apigenin 7-O-glucoronide (8) and naringenin 7-O-ß-D-glucopyranoside (9); and an ellagic acid derivative (10). The extract and compounds were evaluated for their antidiabetic potential by α-amylase and α-glucosidase inhibitory assays. IC50 values of compound 7 (48.1 ± 0.9 µg/mL), compound 8 (48.6 ± 0.1 µg/mL), compound 9 (50.2 ± 0.5 µg/mL) and extract (40.5 ± 0.8 µg/mL) when compared to that of acarbose (26.4 ± 0.3 µg/mL) indicated good α-amylase inhibition. In the α-glucosidase assay, the extract (IC50 = 31.2 ± 0.1 µg/mL), compound 7 (IC50 = 39.5 ± 1.2 µg/mL), compound 8 (IC50 = 40.9 ± 1.3 µg/mL), compound 1 (IC50 = 41.6 ± 1.0 µg/mL), Compound 4 (IC50 = 43.4 ± 0.5 µg/mL), compound 5 (IC50 = 47.6 ± 0.9 µg/mL), compound 6 (IC50 = 46.3 ± 0.2 µg/mL), compound 7 (IC50 = 45.0 ± 0.8 µg/mL), compound 9 (IC50 = 44.8 ± 0.6 µg/mL) and compound 11 (IC50 = 47.5 ± 0.4 µg/mL) all had moderate-to-good inhibitions, compared to acarbose (IC50 = 22.0 ± 0.5 µg/mL). The ability to inhibit α-amylase and α-glucosidase indicates that P. erinaceus and its compounds can lower blood glucose levels by delaying hydrolysis of carbohydrates into sugars, thereby providing a source of natural antidiabetic remedy.

Non-Alkaloid Cholinesterase Inhibitory Compounds from Natural Sources.

Alzheimer's disease (AD) is a severe neurodegenerative disorder of different brain regions accompanied by distresses and affecting more than 25 million people in the world. This progressive brain deterioration affects the central nervous system and has negative impacts on a patient's daily activities such as memory impairment. The most important challenge concerning AD is the development of new drugs for long-term treatment or prevention, with lesser side effects and greater efficiency as cholinesterases inhibitors and the ability to remove amyloid-beta(Aß) deposits and other related AD neuropathologies. Natural sources provide promising alternatives to synthetic cholinesterase inhibitors and many have been reported for alkaloids while neglecting other classes with potential cholinesterase inhibition. This review summarizes information about the therapeutic potential of small natural molecules from medicinal herbs, belonging to terpenoids, coumarins, and phenolic compounds, and others, which have gained special attention due to their specific modes of action and their advantages of low toxicity and high efficiency in the treatment of AD. Some show superior drug-like features in comparison to synthetic cholinesterase inhibitors. We expect that the listed phytoconstituents in this review will serve as promising tools and chemical scaffolds for the discovery of new potent therapeutic leads for the amelioration and treatment of Alzheimer's disease.

Involvement of lytic enzymes and secondary metabolites produced by Trichoderma spp. in the biological control of Pythium myriotylum.

This investigation was aimed to evaluate the antimicrobial activities and involvement of extracellular lytic enzymes produced by four strains of Trichoderma in the inhibition of Pythium myriotylum. Antagonistic effects were tested by dual culture. Activities of lytic enzymes were evaluated from the filtrate of each strain after cultivation in selected media. Organic extracts were obtained from liquid media subsequent to the cultivation of Trichoderma in potato dextrose broth (PDB). Non-volatile organic compounds such as polyphenols and flavonoids were evaluated spectrophotometrically while volatile organic compounds (VOCs) were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The antimicrobial activity of the organic extracts was determined using the poisoning method. Results have shown that all the strains were antagonists against P. myriotylum. T. erinaceum (IT-58), T. gamsii (IT-62), T. afroharzianum (P8), and T. harzianum (P11) that were found to produce cellulase, protease, and xylanase. Over 20 compounds were identified in each extract, including esters, lactones, and organic acids. The organic extracts also contained high amounts of polyphenolic compounds and flavonoids and significantly inhibited the mycelial growth of P. myriotylum. The minimal inhibition concentrations were 80 µg/µL, 40 µg/µL, 20 µg/µL, and 10 µg/µL, for extracts obtained from T. erinaceum (IT-58), T. gamsii (IT-62), T. afroharzianum (P8), and T. harzianum (P11), respectively. There was significant correlation between the production of total polyphenol and flavonoid content and the antagonistic effects of the tested strains.

Comparative Study of the Chemical Compositions and Antioxidant Activities of Fresh Juices from Romanian Cucurbitaceae Varieties.

Cucurbitaceae is a family of health-promoting plants due to their compounds with beneficial effects. The aim of this study was to analyze, for the first time, the chemical composition, the antioxidant activity and the metal chelating properties of fruit juices obtained from four different species of the Cucurbitaceae family cultivated in Romania, namely Momordica charantia, Cucumis metuliferus, Benincasa hispida and Trichosanthes cucumerina. The samples of juice were analyzed by high-performance liquid chromatography (HPLC) and all the four species displayed high levels of the two triterpenes, oleanolic and ursolic acids, and also in phenolic compounds, including catechin, (-)-epicatechin and gallic acid. The juices demonstrated significant antioxidant activity against the free radical 2,2-diphenyl-1-picrylhydrazyl (ranging from 20 to 95%,), a good iron binding ability (ranging from 7.45 ± 0.28% to 86.95 ± 0.97%) and also promising antioxidant potential against the ABTS radical (ranging from 4.97 to 32.60 µETx/mL juice). Our findings raise interesting questions for further research on Cucurbitaceae fruit juices and, consequently, their very good antioxidant potential suggests these fruits should be further explored for their protective effect against oxidative damage. This is the first time the chemical composition and antioxidant activities of fruit juices from these four Romanian Cucurbitaceae varieties have been investigated.

Flavonoid Profiles of Two New Approved Romanian Ocimum Hybrids.

Basil (Ocimum spp.) is a traditional herbal medicine abundant in antioxidants such as phenolic compounds. As part of a diet, this herb is proved to have some roles in decreasing the risk of cancer, and in the treatment of inflammation and neurodegenerative diseases. This study aims to explore the total phenolic and flavonoid content of two new basil hybrids growing in Romania, namely "Aromat de Buzau" (AB) and "Macedon" (MB). The antioxidant capacity of those two species was also analyzed by DPPH and cyclic voltammetry. Six different flavonoids, such as catechin (+), rutin, hyperoside, naringin, naringenin, and genistein, were separated, identified, and quantified by HPLC-DAD chromatography, for the first time, from romanian basil hybrids. The main flavonoid of the extracts was found to be naringin which is present in the highest amount (26.18 mg/kg) in "Aromat de Buzau" (O. basilicum) methanolic extract. These results suggest that dietary intake of these new hybrids can be a source of antioxidant compounds.

Green Accelerated Synthesis, Antimicrobial Activity and Seed Germination Test of Quaternary Ammonium Salts of 1,2-bis(4-pyridyl)ethane.

A family of fifteen quaternary ammonium salts (QAs), bearing the 1,2-bis(4-pyridyl)ethane core, were obtained using for the first time two different green methods, such as microwave (MW) and ultrasounds (US) irradiation, with very good yields and in much shorter times compared to the classical method, and an assay on their antimicrobial action against Escherichia coli (E. coli) was carried out. While 12 to 24 hours were required for complete alkylation of 1,2-bis(4-pyridyl)ethane by reactive halogenated derivatives in anhydrous solvent under reflux conditions, MW and US irradiation reduced the reaction time and the desired products were achieved in a few min. One of the aims of this study was to evaluate the antibacterial potential of the synthesized QAs against pathogenic bacteria, along with their impact on germination activity of wheat seeds (Triticum aestivum L.). The antibacterial activity of the QAs against Escherichia coli was explored by determining the minimum inhibitory concentration (MIC). The MIC values varied from 0.312 to 2.5 mg/mL, highlighting the lowest values attained for the derivatives containing methoxy, chlorine and benzofurane functional groups. The viability of aerobic bacteria was determined with the Tetrazolium/Formazan Test, a method that was found to be the best alternative approach with respect to the difuzimetric method. Seeds of Triticum aestivum L. were used for the evaluation of the germination indicators, such as seed germination (SG), the relative seed germination (RSG), the relative radicle growth (RRG), and the seed germination index (GI). The toxicity studies of QAs 1, 4 and 7, at two different concentrations, showed no inhibitory effect on seed germination.

Exploring New Antioxidant and Mineral Compounds from Nymphaea alba Wild-Grown in Danube Delta Biosphere.

Nymphaea alba is an aquatic flowering plant from the Nymphaeaceae family that has been used for hundreds of years in traditional herbal medicine. The plant is characterized by different phytochemicals, depending on the geographical location. Herein, we have carried out, for the first time, the separation and HPLC-MS/MS identification of some antioxidant compounds, such as polyphenols and flavonoids from N. alba extracts from the Danube Delta Biosphere, and investigated their possible antiradical properties. An ultrasonic method has been exhaustively used for the extraction of the antioxidant compounds from the different anatomic parts of N. alba (fruit, flower, leaf, stem, and root). The extracts that were obtained using ultrasound irradiation showed a large polyphenol (19.42 mg EqGA/100 mg extract) and flavonoid (0.97 mg EqQ/100 mg extract) content. The fruit and flower extracts showed the highest antioxidant activity index (AAI). Among the 27 phytochemical compounds identified in all of the N. alba extracts, rutin and p-coumaric acid were found as the major components. The content of macroelements and microelements in N. alba extracts were compared, and it was found that their concentrations depend on the different anatomic parts of the plant. This research contributes to the study of Nymphaeaceae family, being the first exhaustive phytochemical study of N. alba from a wild population in Romania.

Synthesis and in vitro antimicrobial evaluation of new N-heterocyclic diquaternary pyridinium compounds.

A series of bis-pyridinium quaternary ammonium salts (bis-PyQAs) with different aryl and heteroaryl moieties were synthesized and their antimicrobial activity investigated. The inhibition effect of the compounds was evaluated against bacteria, molds and yeasts; the activities were expressed as the minimum inhibitory concentrations (MIC). The relationships between the structure descriptors (logP, polarizability, polar surface area (2D), van der Waals area (3D)) and the biological activity of the tested bis-PyQAs are discussed.

Sustainable Collagen Film Preparation with Tannins Extracted from Moroccan Pomegranate Byproduct Varieties: Thermal, Structural, and Nanoscaled Studies.

Recently, obtaining collagen films using a cross-linking technique has been a successful strategy. The current investigation used six cross-linker extracts (CE) from six different pomegranate varieties' byproducts to make and characterize collagen-tannin films using acid-soluble collagen (SC). The polymeric film has a yellow hue after CE incorporation. Fourier transform infrared spectroscopy assessed the impact of CE and its successful interaction within the matrix. The shifts verify different interactions between extracts and collagen functional groups, where they likely form new hydrogen bonds, retaining their helix structure without damaging the matrix. Scanning electron microscopy was used to analyze the morphology and fiber size. The average diameter of the fibers was found to be about 3.64 µm. Thermal behaviors (denaturation and degradation) were investigated by thermogravimetric analysis. The weight losses of cross-linked films increased by around 20% compared to non-cross-linked ones. This phenomenon was explained by the absence of telopeptide sections in the collagen helical structure, typically reinforced by lysine and hydroxylysine covalent linkages. Nanoscaled observations were also accomplished using transmission electron microscopy (TEM) on SC and SC-CE. The TEM analysis confirmed the CE polymerization degree effect on the cross-linking density via the overlap sequences, ranging up to 32.38 ± 2.37 nm on the fibril. The prepared biodegradable collagen-tannin film showed higher cross-linking density, which is expected to improve the biomaterial applications of collagen films while exploiting the underrated pomegranate byproducts.

Novel one-pot green synthesis of indolizines biocatalysed by Candida antarctica Lipases.

Marine microorganisms are of considerable interest as a promising source of enzymes with unsuspected potentials as catalysts for chemical synthesis. We describe here an efficient method for one-pot indolizine synthesis that has been developed using lipase A and lipase B from Candida antarctica as biocatalysts. As showed by HPLC/MS analysis, the yield in indolizines was higher in the presence of the biocatalyst than in absence of enzyme. Lipase A, from Candida antarctica, showed high catalytic activity and selectivity for the cycloaddition reactions. When the reactions were performed under ultrasound irradiation, the Candida antarctica lipase catalyzed reactions yielded pure indolozines, in good yields and in very short time.

Ethnopharmacological Value and Biological Activities via Antioxidant and Anti-Protein Denaturation Activity of Morinda lucida Benth and Momordica charantia L. Leaves Extracts from Benin.

Momordica charantia Linn. (Cucurbitaceae), the wild variety of bitter melon, and Morinda lucida Benth (Rubiaceae) were commonly used as a popular folk medicine in Benin. This study aimed to appreciate the ethnopharmacological knowledge and evaluate the antioxidant and anti-inflammatory effects of M. charantia and M. lucida leaves extracts. Semi-structured surveys supported by individual interviews were conducted with herbalists and traditional healers in southern Benin. The antioxidant activities were evaluated by a micro-dilution technique using ABTS and FRAP methods. These activities were supported by cyclic voltammetry analysis. The anti-inflammatory activity was evaluated by the albumin denaturation method. The volatile compounds were analysed by GC-MS analysis. All the respondents involved in this study have good knowledge of the two plants. We identify 21 diseases grouped into five categories of condition. The two plants' extracts possess variable antioxidant capacity. Indeed, all the active extracts of M. charantia presented an IC50 < 0.078 mg/mL, while the extracts of M. lucida had an IC50 up to 0.21 ± 0.02 mg/mL. For anti-inflammatory activity, a dose-response activity (p < 0.001) was observed in the protein denaturation inhibition rate of the extracts. It should be noted that the highest inhibition rate (98.34 ± 0.12) of the albumin denaturation was observed with M. lucida dichloromethane extract. A total of 59 volatile compounds were identified by GC-MS analysis in the extracts of the two plants. The M. charantia ethyl acetate extract shows the presence of 30 different compounds with a relative abundance of 98.83%, while that of M. lucida shows 24 compounds with a relative abundance of 98.30%. These plants are potential candidates to discover new compounds with therapeutic properties that could be used to solve public health problems.

Synthesis and characterization of novel chitosan derivatives (containing dipyridinium quaternary salts) with antimicrobial potential.

Chitosan derivatives are versatile materials, biocompatible and biodegradable, that can be tailor-made to suit specific biomedical applications. In this study, two N-heterocyclic salts (N,N'-diphenacyl-[4,4'-dipyridinium] dibromide (DP) and N,N'-diphenacyl-1,2-bis-(4-pyridinium)ethane dibromide (DPE)) were used for chitosan functionalization to enhance its antimicrobial potential. Physico-chemical characterization of the newly synthesized derivatives (Ch-DP and Ch-DPE) was performed by elemental analysis, spectrometry (UV-Vis, FTIR), electrochemistry (OCP, CV), and electron microscopy (SEM) proving that the highest degree of functionalization was obtained for Ch-DP. The antimicrobial effect of chitosan functionalization was further tested in terms of its interaction with Listeria monocytogenes Scott A, and Staphylococcus aureus ATCC 25923, as Gram-positive bacteria and Escherichia coli ATCC 25922, as Gram-negative bacterium, respectively, showing that the Ch-DP had a good inhibitory activity compared with Ch-DPE.

Phytochemical Characterization and In Vitro Evaluation of the Anti-Sickle Cell Activity of Aqueous and Ethanolic Extracts of Two Medicinal Plants from Niger: Flueggea virosa (Roxb. ex Willd.) Royle and Kigelia africana (Lam.) Benth.

Sickle cell anaemia is a hereditary blood disorder that attacks the red blood cells and deforms them, giving them a sickle shape. Sickle cell anaemia is a serious health problem in the West African country of Niger. Moreover, the cost associated with medical care is very high. The main objective of this study is to contribute to the valorisation of Flueggea virosa (Roxb. ex Willd.) Royle (aerial part), Kigelia africana (lam), and Benth (leaves) from Niger were used to treat sickle cell disease using aqueous and ethanolic extracts of phytochemical compounds. To achieve this objective, the evaluation of anti-sickle cell activity was carried out in vitro using the Emmel technique through the normalisation rate. The analyses showed that the aqueous and ethanolic extracts contained various classes of bioactive substances known for their valuable biological activities. The chemical composition rich in bioactive compounds led to very good results in biological assays. Thus, from a dose of 0.05 mg/mL, the ethanolic extracts of the two plants normalised up to 75% of the sickle cells. As the rate of normalisation was shown to be dose-dependent, at a dose of 10 mg/mL, the ethanolic extracts showed the best rates of sickle cell normalisation, with 95% for F. virosa and 93% for K. africana. Phytochemical screening was used to correlate the secondary metabolite and anti-sickle cell activities of the extracts from the two plants. These results may justify the use of these two species in traditional medicine for the treatment of sickle cell disease in Niger. The inclusion of these plants in phytomedicines could provide significant relief to people suffering from sickle cell disease.

Assessment of Chemical Composition and In Vitro Antioxidant, Antidiabetic, Anticholinesterase and Microbial Virulence-Quenching Effects of Salad Burnet (Sanguisorba minor L.) Harvested from Algeria.

Sanguisorba minor is a medicinal vegetable used in seasoning desserts, juices, and beverages. An evaluation of the total flavonoid, phenolic, tannin and anthocyanin contents indicated that these classes of compounds are distributed variably in the different fractions. In summary, the HPLC-DAD analyses enabled the identification and quantification of thirteen phenolic compounds in an ethyl acetate extract (EAE), nine in a dichloromethane extract (DCME), seven in an aqueous extract (AQE) and four in a butanol extract (BE). Rutin was the most abundant phenolic compound in the BE (278.4 ± 1.20 µg/g) and AQE (32.87 ± 0.23 µg/g) fractions, while apigenin was the most abundant in the DCME (84.75 ± 0.60 µg/g) and EAE (156.8 ± 0.95 µg/g) fractions. The presence of phenolic compounds in the fractions conferred good antioxidant capacity, especially the EAE and DCME fractions, which both exhibited higher antioxidant effects than BHA and α-tocopherol in DPPH• and CUPRAC assays. Additionally, in the ABTS•+ assay, EAE (IC50 = 9.27 ± 0.33 µg/mL) was more active than α-tocopherol (IC50 = 35.50 ± 0.55 µg/mL), and BHA (IC50 = 12.70 ± 0.10 µg/mL). At 200 µg/mL, the fractions inhibited acetylcholinesterase and butyrylcholinesterase as well as α-amylase and α-glucosidase, indicating that they can slow neurodegeneration and hyperglycemia. Minimal inhibitory concentration (MIC) values ranged from 0.312 mg/mL to 1.25 mg/mL, and fractions showed good biofilm inhibition against Staphylococcus aureus and Escherichia coli. The extracts exhibited good violacein inhibition in Chromobacterium violaceum CV12472 and Chromobacterium violaceum CV026, despite the supply of external acyl-homoserine lactone to CV026. The antioxidant, quorum-sensing, antibiofilm and enzyme inhibition attributes indicate the potential for the application of S. minor as a food preservative.

Pharmacological Property and Cytotoxic Effect Showing Antiproliferative Potency in Human Melanoma Cell Lines (A375) of Combretum racemosum P. Beauv. Leaf and Root Extracts Used in Benin.

Combretum racemosum, a plant from the Combretaceae family, is traditionally used in Benin for various health problems. However, scientific research on Beninese samples of this plant is limited. The aim of this study was to identify and assess the bioactive compounds in the plant's leaves and roots. Initial screening involved analyzing powders derived from these parts for total polyphenols, flavonoids, and both condensed and hydrolyzable tannins. The polyphenolic compounds were analyzed using HPLC-DAD-ESI-MS. To evaluate the plant's antimicrobial properties, the agar diffusion method was employed, while FRAP and DPPH assays were used to determine its antioxidant capacity. For anti-inflammatory activity, the study utilized tests for in vitro protein denaturation inhibition and in vivo acute edema induced by carrageenan. Additionally, an antiproliferative assay was conducted using the human melanoma cell line A375. The analysis revealed the presence of significant polyphenolic compounds in both the leaf and root extracts of C. racemosum. Notably, compounds like Pedunculagin, Vescalagin, Casuarictin, and Digalloyl-glucoside were abundant in the leaves, with Vescalagin being especially predominant in the roots. The study also found that the dichloromethane extracts from the leaves and roots exhibited bactericidal effects on a substantial percentage of meat-isolated strains. Moreover, the antioxidant activities of these extracts were confirmed through FRAP and DPPH methods. Interestingly, the dichloromethane root extract showed strong activity in inhibiting thermal albumin denaturation, while the water-ethanol leaf extract demonstrated significant edema inhibition. Finally, the study observed that C. racemosum extracts reduced cell viability in a dose-dependent manner, with leaf extracts showing more pronounced antiproliferative effects than root extracts. These findings highlight the potential of C. racemosum leaves and roots as sources of compounds with diverse and significant biological activities. In conclusion, C. racemosum's leaves and roots exhibit promising biological activities, highlighting their potential medicinal value.