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Background: In the last few decades, the use of plant extracts and their phytochemicals as candidates for the management of parasitic diseases has increased tremendously. Irises are aromatic and medicinal plants that have long been employed in the treatment of different infectious diseases by traditional healers in many cultures. This study aims to explore the potential of three common Iris species (I. confusa Sealy, I. pseudacorus L. and I. germanica L.) against infectious diseases. Their in vitro antiprotozoal potency against Plasmodium falciparum, Trypanosoma brucei brucei, T. b. rhodesiense, T. cruzi and Leishmania infantum beside their cytotoxicity on MRC-5 fibroblasts and primary peritoneal murine macrophages were examined. Methods: The secondary metabolites of the tested extracts were characterized by UPLC-HRMS/MS and Pearsons correlation was used to correlate them with the antiprotozoal activity. Results: Overall, the non-polar fractions (NPF) showed a significant antiprotozoal activity (score: sc 2 to 5) in contrast to the polar fractions (PF). I. confusa NPF was the most active extract against P. falciparum [IC50 of 1.08 μg/mL, selectivity index (S.I. 26.11) and sc 5] and L. infantum (IC50 of 12.7 μg/mL, S.I. 2.22 and sc 2). I. pseudacorus NPF was the most potent fraction against T. b. rhodesiense (IC50 of 8.17 μg/mL, S.I. 3.67 and sc 3). Monogalactosyldiacylglycerol glycolipid (18:3/18:3), triaceylglycerol (18:2/18:2/18:3), oleic acid, and triterpenoid irridals (spirioiridoconfal C and iso-iridobelamal A) were the top positively correlated metabolites with antiplasmodium and antileishmanial activities of I. confusa NPF. Tumulosic acid, ceramide sphingolipids, corosolic, maslinic, moreollic acids, pheophytin a, triaceylglycerols, mono- and digalactosyldiacylglycerols, phosphatidylglycerol (22:6/18:3), phosphatidylcholines (18:1/18:2), and triterpenoid irridal iso-iridobelamal A, were highly correlated to I. pseudacorus NPF anti- T. b. rhodesiense activity. The ADME study revealed proper drug likeness properties for certain highly corelated secondary metabolites. Conclusion: This study is the sole map correlating I. confusa and I. pseudacorus secondary metabolites to their newly explored antiprotozoal activity. [ABSTRACT FROM AUTHOR]

Purpose: The treatment of leishmaniasis, an anthropozoonosis caused by Leishmania protozoa, is limited by factors, such as adverse effects, toxicity, and excessive cost, which has highlighted the importance of novel drugs. In this context, natural products have been considered as sources of antileishmanial agents. This study investigated the leishmanicidal activity of Microgramma vacciniifolia frond lectin (MvFL) on promastigotes and amastigotes of Leishmania amazonensis. Methods: The effects of MvFL on promastigote proliferation and macrophage infection by amastigotes were evaluated and mean inhibitory concentrations (IC50) were calculated. As a safety assessment, the hemolytic capacity of MvFL (6.25–200 µg/mL) against mouse and human erythrocytes was determined. Additionally, the ability of MvFL (6.25–100 µg/mL) to modulate lysosomal and phagocytic activities and the nitric oxide (NO) production by murine peritoneal macrophages was also investigated. Results: After 24 h, MvFL inhibited the proliferation of L. amazonensis promastigotes, with an IC50 of 88 µg/mL; however, hemolytic activity was not observed. MvFL also reduced macrophage infection by amastigotes with an IC50 of 52 µg/mL. Furthermore, treatment with MvFL reduced the number of amastigotes internalized by infected murine peritoneal macrophages by up to 68.9% within 48 h. At a concentration of 25 µg/mL, MvFL stimulated lysosomal activity of macrophages within 72 h, but did not alter phagocytic activity or induce NO production at any of the tested concentrations. Conclusion: MvFL exerts antileishmanial activity and further studies are needed to assess its therapeutic potential in in vivo experimental models of leishmaniasis. [ABSTRACT FROM AUTHOR]

Nanoparticles have emerged as a prominent area of research in recent times, and silver nanoparticles (AgNPs) synthesized via phyco-technology have gained significant attention due to their potential therapeutic applications. Nodularia haraviana, a unique and lesser-explored cyanobacterial strain, holds substantial promise as a novel candidate for synthesizing nanoparticles. This noticeable research gap underscores the novelty and untapped potential of Nodularia haraviana in applied nanotechnology. A range of analytical techniques, including UV-vis spectral analysis, dynamic light scattering spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray powder diffraction, were used to investigate and characterize the AgNPs. Successful synthesis of AgNPs was confirmed through UV-visible spectroscopy, which showed a surface plasmon resonance peak at 428 nm. The crystalline size of AgNPs was 24.1 nm. Dynamic light scattering analysis revealed that silver oxide nanoparticles had 179.3 nm diameters and a negative surface charge of −18 mV. Comprehensive in vitro pharmacogenetic properties revealed that AgNPs have significant therapeutic potential. The antimicrobial properties of AgNPs were evaluated by determining the minimum inhibitory concentration against various microbial strains. Dose-dependent cytotoxicity assays were performed on Leishmanial promastigotes (IC50: 18.71 μgmL−1), amastigotes (IC50: 38.6 μgmL−1), and brine shrimps (IC50: 134.1 μg mL−1) using various concentrations of AgNPs. The findings of this study revealed that AgNPs had significant antioxidant results (DPPH: 57.5%, TRP: 55.4%, TAC: 61%) and enzyme inhibition potential against protein kinase (ZOI: 17.11 mm) and alpha-amylase (25.3%). Furthermore, biocompatibility tests were performed against macrophages (IC50: >395 μg mL−1) and human RBCs (IC50: 2124 μg mL−1). This study showed that phyco-synthesized AgNPs were less toxic and could be used in multiple biological applications, including drug design and in the pharmaceutical and biomedical industries. This study offers valuable insights and paves the way for further advancements in AgNPs research. [ABSTRACT FROM AUTHOR]

The paper describes the synthesis and antimicrobial (antileishmanial, antibacterial and antifungal) activity of some classical hydrazones of benzophenones and of 1,2-diketones. N-(Diaryl) acyl derivatives of these hydrazones have also been synthesized and evaluated. 4,4,-Demthoxybenzil monohydrazone and 4,4′-dimethoxybenzophenone hydrazone showed significant antileishmanial activity. The effect of substituents on the bioactivity is discussed. [ABSTRACT FROM AUTHOR]

Abstract Hematite nanoparticles (NPs) are chemically and thermodynamically more stable among iron oxide NPs therefore these are considered highly suitable for biomedical applications. This work explores Rhus punjabensis extract potential as both reducing and capping agent for phytomediated synthesis of NPs from ferric chloride precursor. The structural, morphological and compositional investigations were carried out with XRD, SEM, TEM, EDS, and FFT. The synthesized NPs were hematite (Fe 2 O 3) with rhombohedral crystal structure of an approximate size of 41.5 ± 5 nm. TEM, FTIR, and TG/DTA indicated phase-pure Fe 2 O 3 formation with controlled size through use of capping agent. Biological activities depict that synthesized NPs had free radical scavenging, antioxidative potential and reducing power activities. These activities are due to phenolic and flavonoid like properties by attachment of different functional groups on the surface of NPs. The NPs exhibited significant Antileishmanial, antibacterial and protein kinase inhibition activities as compared with the corresponding plant extract. NPs depicted cytotoxic effect against HL-60 leukemic and DU-145 prostate cancer cell lines with ED 50 values of 11.9 and 12.79 μg/ml, respectively. The inhibitory effect observed in the NF-κB assay suggested apoptotic potential of hematite NPs to cancerous cells. The green chemistry route reported in this paper for Fe 2 O 3 NP synthesis can be safely and efficiently explored for treatment of cancer and as theranostic agent. Graphical abstract Image 10432 Highlights • Fe2O3 (Hematite) nanoparticle were synthesized using Rhus punjabensis extract. • Characterization of NPs is performed by SEM, XRD, FTIR and FFT, TG/DTA. • NPs exhibited significant antibacterial, Antileishmanial and protein kinase inhibition activities. • Cytotoxic effect against HL-60 leukemic and DU-145 prostate cancer cell lines is also studied. • The inhibitory effect observed in the NF-κB assay suggests apoptotic potential of NPs. [ABSTRACT FROM AUTHOR]

Pyridinium-based oxime compounds have been utilized worldwide as antidotes following exposure to anticholinesterase agents. In the event of combined chemical and biological incident, it is of vital importance to know the ability of antidotes to provide additional protection against biological threats. This paper reports results of in vitro antimicrobial and antiprotozoal activities of a series of quaternary pyridinium oximes against a number of lower pathogenicity BSL-1 and 2 agents. In general, our compound panel had little to no antimicrobial action except for thiophene- and benzothiophene-substituted monoquaternary pyridinium compounds and that showed moderate antibacterial activity against Staphylococus aureus and methicillin-resistant S. aureus with IC values ranging from 12.2 to 17.7 μg/mL. Compounds and also exhibited antileishmanial activity against Leishmania donovani with IC values of 19 and 18 μg/mL, respectively. Another monoquaternary pyridinium compound with a bromobutyl side chain showed antimalarial activity against both a chloroquine sensitive and resistant strains of Plasmodium falciparum with IC values of 3.7 and 4.0 μg/mL, respectively. None of the bisquaternary pyridinium compounds showed antimicrobial or antiprotozoal activity. None of the compounds showed cytotoxic effects toward mammalian kidney fibroblasts. Results of this study indicate that the pyridinium compounds, some of which are already in use as antidotes, do not have significant antimicrobial and antiprotozoal activities and cannot be relied upon for additional protection in the event of combined chemical-biological incident. [ABSTRACT FROM AUTHOR]

The present study was implemented to synthesize green silver nanoparticles from aqueous leaf extract of Nyctanthes arbor-tristis (AgNPNAs) and to analyze their physicochemical properties in evaluating their antileishmanial activity. Formation of AgNPNAs from leaf extract (LE) was evidenced by the change of peak intensity in the fluorescence spectrum. The particles were nearly monodispersed (PDI = 0.134) with hydrodynamic diameter of 67.83 nm and appeared quite stable (zeta potential = −19.1 mV). FESEM study demonstrated nearly spherical shape of AgNPNAs and apparently smooth surface area was identified by AFM. The diameter of AgNPNAs (~ 21 nm) was measured by HRTEM. The amorphous crystal nature, polycrystallinity and low grain size of AgNPNAs were comprehended by the XRD. The crystalline nature was supported from SAED profile. The EDX spectra identified the constituents of AgNPNAs whereas the XPS spectra unraveled the Ag2O state. The FTIR analysis implemented the phytofabricating agent(s) to be attached to the Ag0 via carboxyl group. The leishmanicidal activity of AgNPNAs on Leishmania donovani (MHOM/IN/1983/AG83) was compared with commercial silver nanoparticles (AgNPCOs), AgNO3, miltefosine and leaf extract (LE). The AgNO3 (IC50 = 0.469 ± 0.116 μg/ml), AgNPCOs (IC50 = 4.74 ± 0.221 μg/ml), miltefosine (IC50 = 0.87 ± 0.038 μg/ml) proved their better leishmanicidal efficacy than AgNPNAs (IC50 = 11.46 ± 0.120 μg/ml) and LE was found to be incompetent as parasiticidal. However, AgNPNAs showed greater safety level (IC50 = 136.33 ± 0.881 μg/ml) in normal macrophages (Raw 264.7) than AgNO3 (IC50 = 1.81 ± 0.133 μg/ml), AgNPCOs (IC50 = 10.06 ± 0.719 μg/ml) and miltefosine (IC50 = 18.73 ± 0.9 μg/ml). Altogether, this study revealed the physicochemical properties of AgNPNAs and their biocompatibility in killing L. donovani promastigotes indicating their new identity as potential antileishmanial agent. [ABSTRACT FROM AUTHOR]

In this paper, it is described the synthesis and the evaluation of the leishmanicidal activity of twenty-six eugenol derivatives bearing 1,2,3-triazole functionalities. The evaluation of the compounds on promastigotes of Leishmania amazonensis (WHOM/BR/75/Josefa) showed that eugenol derivatives present leishmanicidal activities with varying degrees of effectiveness. The most active compound, namely 4-(3-(4-allyl-2-methoxyphenoxy)propyl)-1-(4-methylbenzyl)-1 H -1,2,3-triazole ( 7k ) (IC 50  = 7.4 ± 0.8 μmol L −1 ), also targeted Leishmania parasites inside peritoneal macrophages (IC 50  = 1.6 μmol L −1 ) without interfering with cell viability. The cytotoxicity of 7k against macrophage cells presented IC 50 of 211.9 μmol L −1 and the selective index was equal to 132.5. Under similar conditions, compound 7k was more effective than glucantime and pentamidine, two drugs currently in the clinic. In addition, theoretical calculations showed that this compound also presents most physicochemical and pharmacokinetic properties within the ranges expected for orally available drugs. It is believed that eugenol bearing 1,2,3-triazole functionalities may represent a scaffold to be explored toward the development of new agents to treat leishmaniasis. [ABSTRACT FROM AUTHOR]

The underline study focuses on the comparative physicochemical and morphological characteristics, electrochemical analysis, and biological properties of green and chemically synthesized cerium oxide nanoparticles. Green synthesis (G-CeO2-NPs) was carried out using an aqueous root extract of Polygonum bistorta Linn as a reducing and capping agent while chemical synthesis (C-CeO2-NPs) was achieved using ammonium hydroxide (NH4OH) solution via facile precipitation approach. The prepared nanoparticles were investigated for physicochemical, morphological, elemental, and electrochemical properties using multiple characterization techniques while the comparative yield was also determined. Chemical synthesis resulted in cerium oxide nanoparticles (C-CeO2-NPs) with higher yield and specific capacitance compared to green synthesis. However, green synthesized cerium oxide nanoparticles (G-CeO2-NPs) were biologically more active. For instance, G-CeO2-NPs exhibited better antioxidant and bactericidal properties as well as superior leishmanicidal properties, against the amastigote and promastigote stages of the Leishmania tropica, the dimorphic parasite that causes Leishmaniasis. The NPs also demonstrated moderate but comparable anti-Alzheimer's and antidiabetic properties in in vitro studies. Finally, both the chemical and green synthesized CeO2-NPs proved significant hemocompatibility, making cerium oxide nanoparticles, mainly the G-CeO2-NPs, biologically more active, nontoxic, eco-friendly, and favorable candidates for diverse pharmacological studies. [ABSTRACT FROM AUTHOR]

The chemical investigation of the n-hexane fraction from the methanol extract of the stem bark of Symphonia globulifera Linn f., which displayed good in vitro activity against Leishmania donovani NR-48822 promastigotes (IC50 43.11 µg/mL), led to the isolation of three previously unreported polyprenylated benzophenones, guttiferone U (1), V (2)/W (3), and a new tocotrienol derivative named globuliferanol (4), along with 11 known compounds (5–15). Their structures were elucidated based on their NMR and MS data. Some isolated compounds were assessed for both their antileishmanial and cytotoxic activities against L. donovani and Vero cells, respectively. Guttiferone K (5) exhibited the best potency (IC50 3.30 μg/mL), but with low selectivity to Vero cells. The n-hexane fraction and some compounds were also assessed in vitro for their antibacterial activity against seven bacterial strains. All the samples exhibited moderate to potent antibacterial activity (MICs ≤ 15.6 µg/mL) against at least one of the tested strains. [ABSTRACT FROM AUTHOR]

Biogenic methods are an effective alternative to chemical methods in the preparation of nanoparticles. Our study used Crocus caspius extract to synthesize gold nanoparticles (CC-AuNPs) in a green manner. The eco-friendly synthesis of AuNPs was conducted by optimizing the temperature and concentration of HAuCl4 and extract. Synthesized CC-AuNPs were characterized using TEM, SEM, EDX, XRD, FTIR, and UV–Vis spectroscopy. The prepared CC-AuNPs were detected with a size of around 22.66 ± 1.67 nm. The FT-IR analysis of the biomolecules involved in synthesizing CC-AuNPs was performed. Additionally, these biomolecules capped on the AuNPs were revealed by TG/DTA analysis. The EDX study demonstrated the existence of elemental gold. The biosynthesized CC-AuNPs were effectively applied as green catalysts to reduce three organic pollutant dyes—methyl orange (MO), methylene blue (MB), and 4-nitrophenol. In the biological evaluations, the free radical scavenging activity of the eco-friendly CC-AuNPs (DPPH assay) indicated an IC50 value of 29.22 ± 0.47 µg/mL. They displayed effective antibacterial activity against several bacterial strains. Their anticancer activity against AGS and MCF-7 cells showed IC50 concentrations at 48.2 µg/mL and 51.76 µg/mL, respectively. Furthermore, CC-AuNPs presented excellent antileishmanial activity (IC50 = 13.92 µg/mL). Therefore, the green AuNPs are efficient in biomedicine and nanobiotechnology. [ABSTRACT FROM AUTHOR]

Background: In recent years, increasing resistance to synthetic agents, their long-term treatment, and lasting side effects, has faced many problems in treatment of leishmaniasis; so that finding a new high-efficacy antileishmanial drug with minimal side effects seems very necessary. This experimental study was aimed to evaluate the in vitro and in vivo leishmanicidal activity and cellular mechanisms of Astraglus spinosus methanolic extract (ASME) against Leishmania major infection. Materials and Methods: In vitro antileishmanial effect of ASME was evaluated on intracellular amastigotes of L. major in macrophage model. The effect of ASME on the NO production of macrophage cells was determined based on the Griess reaction for nitrites. Effect of ASME on the caspase-3-like activity of L. major promastigotes was performed according to the measuring the rate of color spectrophotometry. The 50% cytotoxic concentrations (CC50) of the ASME on macrophages were measured to assess the cytotoxicity of ASME. In addition, in vivo effects of ASME were evaluated in infected BALB/c mice by measuring of the diameter of CL lesions and parasite load in the tested mice before and after 28 days of therapy. Results: The mean number of intracellular amastigotes of L. major significantly (P < 0.001) decreased with the IC50 value of 36.9 ± 3.012 μg/mL and 44.3 ± 3.012 μg/mL for ASME and MA, respectively. Although more NO was produced by increasing the concentrations of the ASME, but, a notable rise was detected at the IC50 (P < 0.001). ASME especially at the concentrations of ½ IC50 and IC50 significantly provoked the caspase-3 activation, by 10.3%, 25.6%, and 29.8%, respectively. The measured CC50 value of ASME and MA was 463.3 μg/mL and 835 μg/mL, respectively. Treatment of the infected mice with various doses of ASME (50 and 100 mg/kg for 28 days), markedly declined the mean diameter of the CL lesions and parasite load in tested mice. Conclusion: Based on the obtained results, ASME can be considered as a promising herbal drug candidate for the isolation and production of a new alternative agent for CL treatment. As a result, this survey presented adequate results in the parasite eliminating in both in vitro and in vivo assay. Nevertheless, additional studies are needed to elucidate the accurate mechanisms of action of ASME and its effectiveness in clinical subjects. [ABSTRACT FROM AUTHOR]

The abatement of toxic pollutants and drug‐resistant pathogens from water is one of the major environmental issues. In this work, we are reporting the preparation, detailed characterization and photocatalytic degradation, and biological activities of bimetallic oxides (CuO‐SiO2) nanocomposite. For this purpose, CuO, SiO2 nanoparticles, and CuO‐SiO2 nanocomposites were successfully synthesized through sol–gel process. The nanoparticles and nanocomposite were prepared by taking the Cu(NO3)2.3H2O as copper oxide precursor and TEOS as silica precursor using absolute ethanol and water as solvents The molar ratio of TEOS: Glycerol: H2O used was 1.5:1:6.6 respectively. The synthesized nanoparticles and nanocomposites were characterized by using Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and Brunauer–Emmett–Teller (BET). The nanocomposites and individual nanoparticles were then applied as catalysts for their activities toward catalytic/photocatalytic degradation of crystal violet (CV) dye in an aqueous medium. The degradation progress was monitored by UV–Visible spectroscopic analysis. It was found that CuO‐SiO2 nanocomposite shows good photocatalytic activities toward the removal of crystal violet dye as compared to the catalytic activities of its individual constitutes. The antileishmanial and antioxidant activities results indicate that synthesized materials have promising biological attributes. [ABSTRACT FROM AUTHOR]

Recent developments in nanotechnology lead to draw scientist's interest in green synthesis nanoparticles because of their importance in all fields of sciences. This paper is an overview of Ag nanoparticles biosynthesis (AgNPs) by aerial part of Alcea rosea extract. Synthesis procedures were described, with no stabilizers or surfactants. The synthesized AR@AgNPs were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), and UV-Vis analysis. The UV-Vis spectrum of AR@AgNPs shown a characteristic surface plasmon resonance (SPR) peak at 425 nm. Scanning electron microscope revealed spherical shaped with a diameter range of 10-30 nm. Energy dispersive X-ray spectroscopy analysis demonstrated the peak in silver region confirming presence of elemental silver. Evaluation of the antibacterial and antileishmanial activity of biosynthesized silver nanoparticles was performed. AR@AgNPs exhibit effective antibacterial activity against seven ATCC strains of bacteria and eight strains of drug-resistant bacteria. Also, their activity against leishmaniasis was studied on both promastigotes and amastigotes.

In a quest to discover new formulations for the treatment of various parasitic diseases, a series of heteroleptic triorganobismuth(V) biscarboxylates of type [BiR3(O2CR′)2], where R=C6H5 for 1–4 and p-CH3C6H4 for 5–8, were synthesized, characterized and evaluated for their biological potential against L. tropica. All the synthesized complexes were fully characterized by elemental analysis, FT-IR, multinuclear (1H and 13C) NMR spectroscopy and X-ray crystallography. The crystal structures for [BiPh3(O2CC6H4(o-Br))2] (1), [BiPh3(O2CC2H2C6H4)2] (2), [BiPh3(O2CC6H4(m-NO2))2] (3) and [BiPh3(O2CC6H4(2-OH,3-CH3))2] (4) were determined and found to have a distorted pentagonal bipyramidal molecular geometry with seven coordinated bismuth center for 1–3 and for 4 distorted octahedral geometry, respectively. All the synthesized complexes demonstrated a moderate to significant activity against leishmania parasites. A broad analytical approach was followed to testify the stability for (1–8) in solid state as well as in solution and in leishmanial culture M199, ensuring them to be stable enough to exert a significant antileishmanial effect with promising results. Cytotoxicity profile suggests that tris(tolyl) derivatives show lower toxicity against isolated lymphocytes with higher antileishmanial potential. Molecular docking studies were carried out to reveal the binding modes for (1–8) targeting the active site of trypanothione reductase (TR) (PDB ID: 4APN) and Trypanothione Synthetase-Amidase structure (PDB ID 2vob). [ABSTRACT FROM AUTHOR]

Abstract: The paper describes the synthesis and structural characterization of six new diorganotin(IV) compounds 1–6, [R2SnL] and a monoorganotin(IV) derivative, C4H9SnClL (7). Here L = N′-(5-bromo-2-oxidobenzylidene)-N-(oxidomethylene)hydrazine ligand with ONO tridentate chelation capability and R = CH3 (1), C2H5 (2), n-C4H9 (3), C6H5 (4), C8H17 (5), tert-C4H9 (6), The packing diagram offers a supramolecular structure for 1 and a dimeric structure for 4 with distorted square-pyramidal and distorted trigonal geometry, respectively. The different geometry of 1 than 4 can be attributed to the presence of intermolecular non-covalent Sn---O and Sn---H interactions in the former. The antifungal, antibacterial, antiurease and antileishmanial activities of these complexes proved them to be active biologically and may be formulated as new metal-based drugs in future. [Copyright &y& Elsevier]

Cyclic lipopeptides produced by Bacillus species exhibit interesting therapeutic potential. However, their clinical use remains limited due to their low stability, undesirable interactions with host macromolecules, and their potential toxicity to mammalian cells. The present work aims to develop suitable lipopeptide-loaded chitosan nanoparticles with improved biological properties and reduced toxicity. Surfactin and bacillomycin D lipopeptides produced by Bacillus amyloliquefaciens B84 strain were loaded onto chitosan nanoparticles by ionotropic gelation process. Nanoformulated lipopeptides exhibit an average size of 569 nm, a zeta potential range of 38.8 mV, and encapsulation efficiency (EE) of 85.58%. Treatment of Candida (C.) albicans cells with encapsulated lipopeptides induced anti-adhesive activity of 81.17% and decreased cell surface hydrophobicity (CSH) by 25.53% at 2000 µg/mL. Nanoformulated lipopeptides also induced antileishmanial activity against Leishmania (L.) major promastigote and amastigote forms at respective IC50 values of 14.37 µg/mL and 22.45 µg/mL. Nanoencapsulated lipopeptides exerted low cytotoxicity towards human erythrocytes and Raw 264.7 macrophage cell line with respective HC50 and LC50 values of 770 µg/mL and 234.56 µg/mL. Nanoencapsulated lipopeptides could be used as a potential delivery system of lipopeptides to improve their anti-adhesive effect against C. albicans cells colonizing medical devices and their anti-infectious activity against leishmania. [ABSTRACT FROM AUTHOR]

Six new heteroleptic tri-organobismuth(V) complexes (1-6), of general formula, R3Bi(OOCR')2 where R = C6H5 (1-3), p-CH3C6H4 (4-6) and R' represents deprotonated 2-(methylthio)nicotinic acid (1, 4); 3-thiophenecarboxylic acid (2, 5) and 4-chlorosalicylic acid (3, 6) have been synthesized and characterized by FT-IR, NMR (1H, 13C) and single crystal XRD techniques in addition to elemental analyses. The solid-state structure for 3 has also been elucidated by crystallographic data, manifesting its distorted trigonal bipyramidal molecular geometry with a five-coordinate bismuth center. The carboxylate ligand(s) assume a monodentate coordination mode as predicted by IR and then confirmed by XRD data. The antibacterial, antifungal and antileishmanial potential for 1-6 have been evaluated and the preliminary screening data suggest significant to average biological activities. The antileishmanial activity data manifest comparatively lower IC50 value for 5 than the standard drug. A comprehensive study for 1-6 was also undertaken to testify their stability both in solid and solution phases as well as in leishmanial culture M199, which demonstrate high degree of stability that may ensure their significant antileishmanial effect. The % viability values of the organobismuth(V) bis-carboxylates highlight their role as significantly effective compounds, having potential candidature for future drug discovery and development processes. [ABSTRACT FROM AUTHOR]

Background: Plants represent an intricate and innovative source for the discovery of novel therapeutic remedies for the management of infectious diseases. The current study aimed at discovering new inhibitors of Leishmania spp., using anti-leishmanial activity-guided investigation approach of extracts from Diospyros gracilescens Gürke (1911) (Ebenaceae), targeting the extracellular (promastigotes) and intracellular (amastigotes) forms of Leishmania donovani. Methods: The plant extracts were prepared by maceration using H20: EtOH (30:70, v/v) and further fractionated using a bio-guided approach. Different concentrations of D. gracilescens extracts, fractions and isolated compounds were tested in triplicate against L. donovani promastigotes and amastigotes in vitro. The antileishmanial potency and cytotoxicity on RAW 264.7 cells were determined using the resazurin colorimetric assay. The time kill kinetic profile of the most active sample was also investigated. The structures of all compounds were elucidated on the basis of extensive spectroscopic analyses, including 1D and 2D NMR, and HR-ESI-MS and by comparison of their data with those reported in the literature. Results: The hydroethanolic crude extract of D. gracilescens trunk showed the most potent antileishmanial activity (IC50 = 5.84 μg/mL). Further fractionation of this extract led to four (4) fractions of which, the hexane fraction showed the most potent activity (IC50 = 0.79 μg/mL), and seven (07) compounds that exhibited moderate potency (IC50 = 13.69–241.71 μM) against L. donovani. Compound 1-deoxyinositol (7) inhibited the promastigote and amastigote forms of L. donovani with IC50 values of 241.71 μM and 120 μM respectively and also showed the highest selectivity against L. donovani promastigotes (SI > 5.04). To the best of our knowledge, the antileishmanial activity of this compound is being reported here for the first time. The promising hexane fraction showed significant inhibition of parasites growth at different concentrations, but with no evidence of cidal effect over an exposure period of 120 h. Conclusions: The results obtained indicated that the hydroethanolic extract from the D. gracilescens trunk and the derived hexane fraction have very potent inhibitory effect on cultivated promastigotes and amastigotes of L. donovani parasite. The isolated compounds showed a lesser extent of potency and selectivity. However, further structure-activity-relationship studies of 1-deoxyinositol could lead to more potent and selective hit derivatives of interest for detailed drug discovery program against visceral leishmaniasis. [ABSTRACT FROM AUTHOR]

Three organic extracts were prepared from the leaves of Solanum chrysotrichum Schldl. From the methanol extract were isolated two new steroidal saponins (1, 2), and three known compounds (3, 4, and 5). The new saponins were elucidated as 6-α-O-α-L-rhamnopyranosyl-(1 → 3)-β-D-quinovopyranosyl-(25S)-5α-spirostan-3β-ol (1) and 6-α-O-α-L-rhamnopyranosyl-(1 → 3)-β-D-quinovopyranosyl-(23R,25S)-5α-spirostan-3β,23β-ol (2). The structural elucidation of compounds was performed by analysis of 1D and 2D NMR spectral data and HRMS. Antibacterial activity was displayed by the hexane and CH2Cl2 extracts against carbapenem-resistant Pseudomonas aeruginosa (MIC = 250 μg/mL) and carbapenem-resistant Acinetobacter baumannii (MIC = 125 μg/mL). The known saponin (3) was the only compound active against bacteria, showing activity against all the gram-positive bacteria (MIC = 12.5 μg/mL). Antitubercular activity was observed only for the hexane extract (MIC = 250 μg/mL). The antifungal and antileishmanial activities were determined for the steroidal saponins, but they were devoid of antifungal activity at the concentrations tested. Antileishmanial activity was shown only by the saponin (1) (IC50: 21.64 ± 1.21 μg/mL). [ABSTRACT FROM AUTHOR]

In the present study, green silver nanoparticles (Ag2ONPs) were prepared from aqueous and ethanolic leaves extract of Rhamnus virgata in a facile, green, cost‐effective, and eco‐friendly way. The color changes from light brown to brownish black determined the synthesis of Ag2ONPs(Aq) and Ag2ONPs(Et). The phytofabrication of Ag2ONPs was confirmed using various spectroscopic and microscopic techniques: energy‐dispersive X‐ray spectroscopy, dynamic light scattering, ultraviolet–visible spectroscopy, Fourier‐transform infrared, X‐ray powder diffraction, Raman, scanning electron microscopy, and transmission electron microscopy. Detailed in vitro biological activities determined significant biopotentials for Ag2ONPs. The Ag2ONPs(Aq) and Ag2ONPs(Et) were investigated for anticancer potential against HUH‐7 (IC50: 9.075 μg/ml for Ag2O(Aq) and 25.66 μg/ml for Ag2O(Et)) and HepG2 (IC50: 25.18 μg/ml for Ag2O(Aq) and IC50: 27.74 μg/ml for Ag2O(Aq)) cell lines. Concentration‐dependent cytotoxicity was performed against brine‐shrimps (IC50: 36.04 μg/ml for Ag2O(Aq) and 28.82 μg/ml for Ag2O(Et)) and Leishmanial parasite (amastigotes and promastigotes). Disc‐diffusion method revealed significant antimicrobial activities. In addition, significant enzyme inhibitory activity and antiradical potentials were studied. The hemocompatible nature of Ag2ONPs(Aq) and Ag2ONPs(Et) was revealed using biocompatibility tests. In conclusion, the green Ag2ONPs(Aq) and Ag2ONPs(Et) are nontoxic and biocompatible and has shown significant biological activities. We further encourage in vivo studies to ensure biosafety and biocompatibility, so that they can be effectively utilized in nano‐pharmaceutical industries. [ABSTRACT FROM AUTHOR]

A series of trifluoromethylated pyrazole thiosemicarbazone, trifluromethylated pyrazole isothiosemicarbazone, and trifluoromethylated pyrazole 2-amino-1,3,4-thiadiazole hybrids were synthesized and evaluated in vitro against the promastigote form of Leishmania amazonensis and the epimastigote form of Trypanosoma cruzi , the pathogens causing the neglected tropical diseases leishmaniasis and Chagas disease, respectively. The results show the potential of these compounds regarding their antiparasitic properties. Studies on the structure-activity relationship demonstrated that compounds containing a bulky group at the para position of the phenyl ring attached to the 5-position of the pyrazole core had better antiparasitic effects. Among the substituents attached at the 3-position of the pyrazole ring, the insertion of the 2-amino-1,3,4-thiadiazole nucleus led to the most potent compounds compared to the thiosemicarbazone derivative. [ABSTRACT FROM AUTHOR]

Green synthesis of nanoparticles using plants has become a promising substitute for the conventional chemical synthesis methods. In the present study, our aim was to synthesize chromium oxide nanoparticles (Cr2O3NPs) through a facile, low-cost, ecofriendly route using leaf extract of Rhamnus virgata (RV). The formation of Cr2O3NPs was confirmed and characterized by spectroscopic profile of UV--Vis, EDX, FTIR, and XRD analyses. The UV-visible spectroscopy has confirmed the formation of Cr2O3NPs by the change of color owing to surface plasmon resonance. The bioactive functional groups present in the leaf extract of RV involved in reduction and stabilization of Cr2O3NPs were determined by FTIR analysis. Based on XRD analysis, crystalline nature of Cr2O3NPs was determined. The morphological shape and elemental composition of Cr2O3NPs were investigated using SEM and EDX analyses, respectively. With growing applications of Cr2O3NPs in biological perspectives, Cr2O3NPs were evaluated for diverse biopotentials. Cr2O3NPs were further investigated for its cytotoxicity potentials against HepG2 and HUH-7 cancer cell lines (IC50: 39.66 and 45.87 µg/ml), respectively. Cytotoxicity potential of Cr2O3NPs was confirmed against promastigotes (IC50: 33.24 µg/ml) and amastigotes (IC50: 44.31 µg/ml) using Leishmania tropica (KMH23). The Cr2O3NPs were further evaluated for antioxidants, biostatic, alpha-amylase, and protein kinase inhibition properties. Biocompatibility assay was investigated against human macrophages which confirmed the nontoxic nature of Cr2O3NPs. Overall, the synthesized Cr2O3NPs are biocompatible and nontoxic and proved to possess significant biopotentials. In future, different in vivo studies are needed to fully investigate the cytotoxicity and mechanism of action associated with these Cr2O3NPs. [ABSTRACT FROM AUTHOR]

This study attempts to obtain and test the bioactivities of leaf extracts from a medicinal plant, Geranium wallichianum (GW), when conjugated with zinc oxide nanoparticles (ZnONPs). The integrity of leaf extract-conjugated ZnONPs (GW-ZnONPs) was confirmed using various techniques, including Ultraviolet-visible spectroscopy, X-Ray Di raction, Fourier Transform Infrared Spectroscopy, energy-dispersive spectra (EDS), scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The size of ZnONPs was approximately 18 nm, which was determined by TEM analysis. Additionally, the energy-dispersive spectra (EDS) revealed that NPs have zinc in its pure form. Bioactivities of GW-ZnONPs including antimicrobial potentials, cytotoxicity, antioxidative capacities, inhibition potentials against -amylase, and protein kinases, as well as biocompatibility were intensively tested and confirmed. Altogether, the results revealed that GW-ZnONPs are non-toxic, biocompatible, and have considerable potential in biological applications. [ABSTRACT FROM AUTHOR]

To survive in a very competitive environment, marine macroalgae had to evolve defense strategies, resulting in an enormous diversity of compounds from different metabolic pathways. These secondary metabolites have been explored by the pharmaceutical industries in order to generate new drugs to treat several diseases. Recent publications in drug research from natural sources have indicated algae as an interesting choice to provide novel drugs to fulfill this gap. This review highlights algal metabolites that showed bioactivities suggesting their potential against neglected diseases. Drug discovery for neglected diseases has been overlooked by the Big Pharmas, mainly because they affect poor people, most of them living in developing countries. Moreover, this review shows the commercial application of the most explored chemicals from algae such as terpenes, phenols, quinones, macrolides, alkaloids, lipids, chromones, and other related metabolites and an overview regarding the status of green extraction technologies for seaweeds and their concepts. [ABSTRACT FROM AUTHOR]

Aim: To investigate the physical and biological properties of Silybum marianum inspired ZnO nanoparticles (NPs), Ag–ZnO heterostructures. Experiment: Nanoparticles were characterized using ultraviolet–visible and infrared spectroscopy, x-ray diffraction, high resolution electron microscopy, ζ potential and thermo-gravimetric analysis etc. Results: Ag–ZnO–NPs indicated slightly higher antimicrobial potential then ZnO–NPs. Good antileishmanial (IC50 = 246 μg/ml for Ag–ZnO; 341 μg/ml for ZnO) and antioxidant potential while moderate enzyme inhibition is reported. 2, 2-Diphenyl 1-picrylhydrazyl radical scavenging of Ag–ZnO was higher relative to ZnO–NPs. Nanocosmaceutical formulation of nanoparticles indicated stable antimicrobial performance. Conclusion: Biosynthesized nanoparticles indicated interesting biological properties and should be subjected to further research to establish their pharmacological relevance. [ABSTRACT FROM AUTHOR]

Aqueous floral extracts of Callistemon viminalis were used to synthesize Fe2O3 nanoparticles (IONPs) which were intensively characterized through UV-vis, X-ray diffraction, HR-SEM/HR-TEM, Fourier- transform infrared spectroscopy (FTIR) and energy dispersive X-ray spectroscopy (EDS). Their physical properties were studied in response to different annealing temperatures. It was observed that the increase in the annealing temperature produced small-sized nanoparticles. The nanoparticle size was calculated as 32, 26 and 22 nm for annealing at 300, 400 and 500 °C, respectively. The magnetic nature of the bioinspired IONPs was revealed by superconducting quantum interference device (SQUID). Their antibacterial potential was investigated against nine pathogenic bacterial strains (gram positive and gram negative) using disc diffusion method while their MIC was calculated using broth dilution assay. Bioinspired IONPs were found to be highly effective against HepG2 cells (IC50=20 µg/mL). Moderate antileishmanial activities against the promastigotes and amastigotes cultures are reported. Moderate acetylcholine esterase (AchE), butylcholine esterase (BchE) and α-Glycosidase inhibition are reported. Additional assessment of the biocompatibility was performed using haemolytic activity on the freshly isolated human red blood cells and macrophages. Furthermore, the antioxidant activities, including TAC, DPPH and TRP were also performed. Our results indicate that the biogenic and magnetic Fe2O3 can be used for diverse biomedical applications. [ABSTRACT FROM AUTHOR]

Background: Plants have served either as a natural templates for the development of new chemicals or a phytomedicine since antiquity. Therefore, the present study was aimed to appraise the polarity directed antioxidant, cytotoxic, protein kinase inhibitory, antileishmanial and glucose modulatory attributes of a Himalayan medicinal plant- Quercus dilatata. Methods: Total phenolic and flavonoid contents were determined colorimetrically and various polyphenols were identified by RP-HPLC analysis. Brine shrimp lethality, SRB and MTT assays were employed to test cytotoxicity against Artemia salina and human cancer cell lines respectively. Antileishmanial activity was determined using standard MTT protocol. Glucose modulation was assessed by α-amylase inhibition assay while disc diffusion assay was used to establish protein kinase inhibitory and antifungal spectrum. Results: Among 14 extracts of aerial parts, distilled water-acetone extract demonstrated maximum extract recovery (10.52% w/w), phenolic content (21.37 ± 0.21 µg GAE/mg dry weight (DW)), total antioxidant capacity (4.81 ± 0.98 µg AAE/mg DW) and reducing power potential (20.03 ± 2.4 µg/mg DW). On the other hand, Distilled water extract proficiently extracted flavonoid content (4.78 ± 0.51 µg QE/mg DW). RP-HPLC analysis revealed the presence of significant amounts of phenolic metabolites (0.049 to 15.336 µg/mg extract) including, pyrocatechol, gallic acid, catechin, chlorogenic acid, p-coumaric acid, ferulic acid and quercetin. Highest free radical scavenging capacity was found in Methanol-Ethyl acetate extract (IC50 8.1 ± 0.5 µg/ml). In the brine shrimp toxicity assay, most of the tested extracts (57%) showed high cytotoxicity. Among these, Chloroform-Methanol extract had highest cytotoxicity against THP-1 cell line (IC50 3.88 ± 0.53 µg/ml). About 50% of the extracts were found to be moderately antiproliferative against Hep G2 cell line. Methanol extract exhibited considerable protein kinase inhibitory activity against Streptomyces 85E strain (28 ± 0.35 mm bald phenotype at 100 µg/disc; MIC = 12.5 µg/disc) while, Chloroform extract displayed maximum antidiabetic activity (α-amylase inhibition of 21.61 ± 1.53% at 200 µg/ml concentration). The highest antileishmanial potential was found in Ethyl acetate-Acetone extract (12.91 ± 0.02% at 100 µg/ml concentration), while, Q. dilatata extracts also showed a moderate antifungal activity. Conclusion: This study proposes that multiple-solvent system is a crucial variable to elucidate pharmacological potential of Q. dilatata and the results of the present findings prospects its potential as a resource for the discovery of novel anticancer, antidiabetic, antileishmanial and antioxidant agents. [ABSTRACT FROM AUTHOR]

Background: Tributyltin (IV) compounds are promising candidates for drug development. In the current study, we evaluated in-vitro and in-silico profile of carboxylate derivatives of tributyltin (IV) complexes. Methods: ADMET and drug-likeliness properties were predicted using MetaPrint2D React, preADMET, SwissADME and Molsoft tools. SwissTargetPrediction predicted molecular targets for compounds. In-vitro bioactivity was evaluated by quantifying cytotoxicity against HepG2, THP-1 cell lines, isolated lymphocytes and leishmania promastigotes as well as measuring protein kinase (PK) inhibition activity. Results: Results indicate partial compliance of compounds with drug-likeliness rules. Ch-409 complies with WDI and Lipinski rules. ADMET profile prediction shows strong plasma protein binding except for Ch-409, low to high GI absorption and BBB penetration (Cbrain/Cblood = 0.942-11; caco-2 cells permeability 20.13-26.75 nm/sec), potential efflux by P-glycoprotein, metabolism by CYP3A4, medium inhibition of hERG, mutagenicity and capacity to be detoxified by glutathionation and glucuronidation. Molecular targets include proteases, enzymes, membrane receptors, transporters and ion channels where Ch-409 targets membrane receptors only. Compounds are significantly (p < 0.05) cytotoxic against HepG2 cell line and leishmania as compared with normal isolated lymphocytes. Ch-459 indicates highest toxicity against leishmania (mortality 97.9 ± 3.99%; LC50 0.323 ± 0.002 μg/mL) whereas Ch-409 possesses maximum cytotoxicity against HepG2 cell line (IC50 0.08 ± 0.001 μg/mL) as well as 97.5 ± 1.98% (LC50 0.954 ± 0.158 μg/mL) mortality of leishmania promastigotes. It was observed that antileishmanial effect was reduced by 16.38%-34.38% and 15-38.2% in the presence of NaN3 and mannitol respectively. PK inhibition and reactive oxygen species production are possible mechanisms for cytotoxicity. Conclusions: Selected carboxylate derivatives of tributyltin (IV) complexes possess significant antileishmanial and cytotoxic potential. These are promising compounds for the development of antileishmanial and anticancer drugs. [ABSTRACT FROM AUTHOR]

Background: The role of plants for discovery of therapeutic potential accentuates the need to know their biological attributes. The present study aims to comprehend the biological attributes of Rhus punjabensis, an unexplored traditional medicinal plant. Methods: Leaf and stem extracts of R. punjabensis prepared in 11 different organic solvents are evaluated for multimode antioxidant potential, total phenolic and flavonoid contents were determined through colorimetric assays, HPLC-DAD analysis was carried out for quantification of various polyphenols in extracts. Brine shrimp lethality, SRB and MTT assays were used to elucidate plant's cytotoxic and antileishmanial potentials. Disc diffusion assay was used to elucidate the protein kinase inhibitory, antibacterial and antifungal spectrum. Results: Ethanol + ethyl acetate yielded maximum extract recovery from leaf (6.11 ± 1.09% w/w), total phenolic content (80.5 ± 2.18 µg GAE/mg extract) and reducing power potential (165.4 ± 2.29 µg AAE/mg extract).Maximum flavonoid content (30.50 ± 1.11 µg QE/mg extract) and highest DPPH based free radical scavenging activity (IC50 11.4 ± 2.07) was exhibited by the methanol + chloroform leaf extract. The methanol extract showed maximum total antioxidant capacity (74.5 ± 2.25 µg AAE/mg DW), protein kinase inhibitory (12.5 ± 1.10 bald phenotype at 100 µg/disc) and antifungal (MIC = 25 µg/disc against Aspergillus flavus) potential. Reverse phase HPLC-DAD based quantification reveals presence of gallic acid, apigenin, rutin and catechin in various extracts. Brine shrimp lethality assay demonstrated most extracts as highly cytotoxic (LC50 < 50 µg/mL) whereas chloroform extract of leaf demonstrated maximuminhibition against human leukemia cell line (IC50 7.80 ± 0.01 µg/mL). A significant activity against leishmanial promastigotes was demonstrated by n-hexane leaf extract (IC50 = 15.78 ± 0.15 µg/mL). A better antibacterial activity,by the extracts, against Gram positive strains as compared to Gram negative was observed. Conclusions: Results recommend multiple-solvent system as a critical factor to sumptuous the biological prospective of R. punjabensis and propose it to be a useful natural hub for the discovery of novel antioxidant, anticancer, antileishmanial and antimicrobial agents. [ABSTRACT FROM AUTHOR]

Background: Different species of Croton are used in traditional Amazonian medicine. Among the popular uses are treatment of bacterial diseases, poorly healing wounds and fevers. Objective: This study evaluated the antileishmanial, antiplasmodial and antimicrobial activities of the extracts and diterpenes of Croton palanostigma Klotzsch (Euphorbiaceae). Materials and Methods: Leaves and bark were extracted with dichloromethane and methanol. The bark dichloromethane extract (BDE) was chromatographed on a column, obtaining cordatin and aparisthman. The extracts and diterpenes were assayed thought agar disk diffusion method and their bactericidal or fungicidal effects were evaluated by minimum bactericidal or fungicidal concentration. The antiplasmodial activity was evaluated after 24 and 72 h of exposition. The antileishmanial activity was performed on promastigotes forms of Leishmania amazonensis. Results: The bark methanol extract (BME) and cordatin were not active against any microbial strains tested; BDE and leaves methanol extract (LME) were positive for Pseudomonas aeruginosa and aparisthman was positive for Candida albicans. In the determination of the minimum bactericidal concentration, neither of them were active in the highest concentration tested. The extracts and diterpenes were inactive in Plasmodium falciparum, except the LME in 72 h. Any extract was shown to be active in promastigote forms of L. amazonensis. Conclusion: These results indicate that the BDE and LME did not inhibit the bacterial growth, then they probably had bacteriostatic effect. LME presented activity in P. falciparum. [ABSTRACT FROM AUTHOR]

Aim: The effect of astrakurkurone, a novel triterpene, isolated from Indian mushroom Astraeus hygrometricus has been investigated to elucidate the mechanisms involved in selective cell death of Leishmania donovani. Materials & methods: The hypotheses were investigated using flow-cytometry, scanning electron microscopy and confocal microscopy. Results: The time dependent elevation of astrakurkurone-induced reactive oxygen species (ROS) was found intimately associated with apoptosis. The involvement of ROS in promastigote death was found confirmed as NAC and GSH could decrease the ROS level and restored the mitochondrial membrane potential (Δ Ψ m). It also inhibited the intracellular amastigotes. Conclusion: We claim the present invention as substantial in depth evidences that mushroom derived active molecules can be exploited as target specific, comparatively nontoxic leads for antileishmanial therapy. [ABSTRACT FROM AUTHOR]

A series of N, N, N′-trisubstituted thioureas ( 1-12) and their Ni(II) complexes ( 1a-12a) were synthesized and characterized by multinuclear (H and C) NMR, FT-IR spectroscopy and LC-MS techniques in combination with elemental analysis. The crystal structures of both ligands and Ni(II) chelates of type Ni(L- O, S) were determined by single crystal X-ray diffraction analysis. All the complexes were adopted to have square planar geometry, where the N, N, N′-trisubstituted thioureas showed bidentate mode of coordination at nickel centre through oxygen and sulfur atoms. The synthesized complexes were screened for potential inhibitors of Jack bean urease. Compounds 1a and 3a were observed as most potent inhibitors of urease exhibiting IC values of 1.17 ± 0.12 and 1.19 ± 0.41 µM, respectively. Cytotoxicity assay on lung carcinoma (H-157) and kidney fibroblast (BHK-21) cell showed that compounds were significant anticancer agents. Additionally, the complexes were tested against Leishmania major and found to be potent antileishmanial agents. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a major protozoal disease threatening the lives of 350 million people throughout the world. However, the therapeutic options for the disease are limited. In the present study, the antiprotozoal activity of the latex obtained from the Ethiopian plant Aloe calidophila Reynolds was evaluated by in vitro testing against Leishmania aethiopica and Leishmania major. It was found that the latex possesses moderate activity against both parasites with IC50 values of 64.05 and 82.29 μg/mL, respectively. Phytochemical investigation resulted in the isolation of three anthrones identified as aloinoside, aloin, and microdontin on the basis of IR, MS, 1H NMR, and 13C NMR spectral data. The isolated compounds showed strong antileishmanial activity with IC50 values ranging from 1.76 to 6.32 μg/mL against L. aethiopica and from 2.09 to 8.85 μg/mL against L. major. Although these values were higher than those of amphotericin B (IC50 = 0.109 and 0.067 μg/mL), the selectivity indices (813.35 and 694.90, respectively, against L. aethiopica and L. major) of aloinoside were much better than those of the standard drug (423.49 and 688.96). The results indicate that the isolated compounds have the potential to be used as a scaffold for the development of safe and cost-effective antileishmanial agents. [ABSTRACT FROM AUTHOR]

Two novel organoantimony(V) and two organobismuth(V) complexes of the type ML2 were synthesized, with L = acetylsalicylic acid (HL1) or 3-acetoxybenzoic acid (HL2) and M = triphenylantimony(V) (M1) or triphenylbismuth(V) (M2). Complexes, [M1(L1)2] (1), [M1(L2)2]·CHCl3 (2), [M2(L1)2], (3) and [M2(L2)2] (4), were characterized by elemental analysis, IR and NMR. Crystal structures of triphenylantimony(V) dicarboxylate complexes 1 and 2 were determined by single crystal X-ray diffraction. Structural analyses revealed that 1 and 2 adopt five-coordinated extremely distorted trigonal bipyramidal geometries, binding with three phenyl groups in the equatorial position and two deprotonated organic ligands (L) in the axial sites. The metal complexes, their metal salts and ligands were evaluated in vitro for their activities against Leishmania infantum and amazonensis promastigotes and Staphylococcus aureus and Pseudomonas aeruginosa bacteria. Both the metal complexes showed antileishmanial and antibacterial activities but the bismuth complexes were the most active. Intriguingly, complexation of organobismuth(V) salt reduced its activity against Leishmania, but increased it against bacteria. In vitro cytotoxic test of these complexes against murine macrophages showed that antimony(V) complexes were the least toxic. Considering the selectivity indexes, organoantimony(V) complexes emerge as the most promising antileishmanial agents and organobismuth(V) complex 3 as the best antibacterial agent. [ABSTRACT FROM AUTHOR]