Curcumin Ligand Research Articles

Water-Soluble Curcumin Derivatives Including Aza-Crown Ether Macrocycles as Enhancers of their Cytotoxic Activity.

The synthesis of three novel curcumin derivative compounds, featuring aza-crown ether macrocycles of various sizes (aza-12-crown-4, aza-15-crown-5, and aza-18-crown-6), is described. The incorporation of these aza-crown macrocycles significantly enhances their water solubility, positioning them as groundbreaking instances of curcumin derivatives that are fully soluble in aqueous environments. These curcumin ligands (L1, L2, and L3) were then reacted with zinc acetate to afford the coordination metal complexes (L1-Zn, L2-Zn, and L3-Zn). Comprehensive characterization of all compounds was achieved using various analytical techniques, including 1D and 2D NMR spectroscopy, ATR-FTIR spectroscopy, mass spectrometry (ESI+), elemental analysis and UV-Vis spectroscopy. The in vitro cytotoxic activity of both, ligands and complexes were evaluated on three human cancer cell lines (U-251, MCF-7, and SK-LU-1). Compared to conventional curcumin, these compounds demonstrated improved antiproliferative potential. Additionally, a wound healing assay was conducted to assess their antimigration properties. The obtained results suggest that these modifications to the curcumin structure represent a promising approach for developing therapeutic agents with enhanced cytotoxic properties.

Complexation process and binding parameters of curcumin and short amylose with V7-type helix structure

Pre-formed V7-type short amylose (SA) could interact with curcumin to form inclusion complex (IC) thereby to improve the stability of curcumin. However, the complexation mechanism of V7-type SA and curcumin is not clear, which limit the improvement of inclusion efficiency. To obtain a starch nanocarrier with high loading capacity, the encapsulation process and interaction parameters of V7-type SA-curcumin IC was studied. The analysis results demonstrated that stoichiometric ratio value of the SA-curcumin complex was around 1. V7-type SA performed excellently in the delivery of curcumin attributing to their high loading capacity (over 20 %). It was found that curcumin could enter into the pre-formed helical cavity of SA to form an IC. The conformation change of SA caused the reduction in the interaction ratio in the last 20 ns of simulation. However, SA and curcumin always remained complexation status during the simulation. Hydrogen bonds (H-bonds) and hydrophobic interaction were the most critical acting forces involved in the formation and stability of V7-type SA-curcumin complex. Molecular docking presented that H-bonds interaction between curcumin ligand and V7-type SA chain (O3 at the 25th glucose unit, and O6 at the 17th and 20th glucose units) were found. Furthermore, the hydrophobic interactions were discovered between curcumin ligand and SA chain (18th, 19th, 21st, 22nd and 23rd glucose units). Short abstractTo obtain a nanocarrier with high loading capacity, the interacting mechanism of curcumin and V-type short amylose (SA) was studied. The results demonstrated that curcumin could enter into the pre-formed helical cavity of SA to form an inclusion complex. SA and curcumin always remained complexation status during the simulation. Hydrogen bonding and hydrophobic interaction were the most critical acting forces involved in the formation and stability of V7-type SA-curcumin complex.

Separation trace amounts of copper ion by solid-phase extraction with carbon-based sorbent prior to flame atomic absorption spectrometry

ABSTRACT In this research, a carbon adsorbent modified with curcumin ligand was utilised in the solid-phase extraction procedure. This method was coupled with flame atomic absorption spectrometry to pre-concentrate and separate trace amounts of copper ions in aqueous solutions. Different experimental parameters, including pH, eluent type and concentration, adsorbent dose, extraction time and sample volume, were studied and optimised. The obtained optimum conditions for the proposed method were: pH of solution, 4.8; extraction time, 9 min; adsorbent dose, 0.01 g; type and concentration of eluent, 1:1 mixture of HCl and HNO3 0.5 mol L−1. Under optimal conditions, the pre-concentration factor of 400.0 and linear range values of the method were 0.031–1.875 µg/L and 12.5–750 µg/L for copper ions in the initial and final solutions, respectively. The relative standard deviation (RSD) for seven replicate detections of 0.05 µg L−1 of copper ion in initial solution was calculated as 2.2%. Furthermore, the detection limit of 0.008 µg L−1 was determined for the suggested method. In order to investigate the selectivity of modified carbon adsorbent, the influence of some interfering ions on the extraction and recovery of Cu (II) was studied. Finally, the present method was employed for the determination of copper ions in real water samples and standard alloys.

Spectral-luminescent properties of Zn(II) curcuminates

1,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (curcumin, Cur) and mono- and mixed Zn(II) complexes based on it were synthesized using the improved method. It was established that curcumin forms metal chelates of the composition ZnCur22Н2О and Zn(Cur)2Phen with the zinc ion. Coordination of the curcumin ligand with the central atom is bidentate cyclic through the -diketone group, and the ortho-methoxyphenol fragment of Cur does not participate in chelation. The fluorescent properties of all synthesized compounds were studied. It was shown that the complex formation of zinc with curcumin causes an increase in the relative intensity of fluorescence and a shift of the emission band to the long-wave region. This indicates both the complexation process and the sensitizing effect of the zinc ion. When phenatroline is added to the zinc(II) complex, the fluorescence emission maximum undergoes a bathochromic shift compared to the ZnCur2 monoligand complex, and the relative fluorescence intensity decreases by 2.5 times. The shift of the radiation maximum to the region of low energies is due to the coordination of the phenathroline molecule to metal ions; and the decrease in emission is due to the shielding ability of the phenathroline donor molecule in relation to the weaker curcumin donor, which increases the number of non-radiative energy losses caused by its inefficient transfer due to the large energy gap between the triplet levels of the ligands.

Synthesis, Characterization and Bioactivity Study of Few Metal Complexes of Curcumin with 2-(1H-Benzimidazol-2-yl) Aniline

We have synthesized many metal (II) complexes using curcumin L1 as the major ligand and 2-(1H-Benzimidazol-2-yl) aniline L2 as a supporting ligand. The complexes were characterized by spectroscopy methods such as; molar conductivity, elements microanalysis, Fourier-transform spectroscopy (FT-IR), UV-vis, and mass spectroscopy. Both curcumin ligands and L2 were found to be capable of binding to M(II) and metal ions via their two N atoms, according to the data. The formula for the complexes is the same. [M (L1)(L2)H2OCl], where M is Ni(II), Co(II), Cu(II), Cd(II), and Hg(II) (II). Octahedral complexes are proposed for the prepared compounds. The bio-actives suggested that the complexes are effective against bacteria and fungus on a mild to moderate level.

Synthesis, characterization and evaluation of antibacterial activity of copper(II)-curcumin complex against staphylococcus aureus

Curcumin, a phytochemical from turmeric, and its derivatives have been extensively investigated from both chemical and biological strategies. However, the main problem encountered while using curcumin in clinical trials is its poor solubility and rapid degradation, resulting in its low levels in tissues, thus decreasing the medicinal effect of curcumin. To overcome these problems several synthetic approaches have been carried out to prepare new derivatives possessing better properties. Curcumin as a β-diketone ligand can act as chelating ligands toward a variety of metals to form stable complexes. Some studies showed that a metal-curcumin complex displayed potential medicinal activities. In this work, a copper(II)-curcumin complex was synthesized in a two-step procedure: (i) curcumin was separated from commercial turmeric powder using chromatography techniques and (ii) the copper(II) chloride (1 eq.) and pure curcumin (2 eq.) were mixed together in ethanol. The mixture was stirred at 60 oC for 3 hours to afford a stoichiometric copper(II)-curcumin complex. The curcumin ligand and its copper(II) complex were characterized by UV-Vis, IR, NMR spectroscopic methods, from which it was found that copper atoms are coordinated through keto-enol groups of two curcumin molecules. The ground state spectral features of the copper(II)-curcumin complex were consistent with that of the 1:2 copper(II)-curcumin complex. The antibacterial activities of curcumin ligand and its complex were evaluated against Staphylococcus aureus (ATCC 6538) using a well diffusion method on nutrient agar. The results showed that the inhibitory activity was not observed for free curcumin at any concentrations while the copper(II)-curcumin complex exhibited the inhibition zones (mm) of 7.8, 11.6 and 14.9 at various concentrations (mg/mL) of 1.0, 5.0 and 15.0, respectively.

Synthesis and photophysical properties of metal complexes of curcumin dyes: Solvatochromism, acidochromism, and photoactivity

Curcumin and its dyes have attracted attention due to their environment-sensitivity and optical properties. However, the free molecule has low photoactivity, which is a limitation for use in photodynamic therapy. To overcome this limitation, we proposed the chelation of a D-π-A-π-D curcumin dye (1) with the metals Cu (II) and Pd (II). The photophysical properties of the curcumin dyes were investigated in different solvents, using UV–vis spectroscopy and time-resolved/steady-state fluorescence techniques. In our results, all curcumin dyes exhibited a positive solvatochromism from non-polar to polar solvents, with the Stokes’ shift in the range of 1895–4970 cm−1. The acidochromism studies were performed in chloroform solution and TLC plates using trifluoroacetic acid (TFA). The results exhibited a negative acidochromism and fluorescence quenching upon gradual addition of TFA, demonstrating reversibility upon addition of triethylamine (TEA). The main mechanism which influences the solvatochromism/acidochromism is the ICT system and fluorescence lifetime decays exhibited mono-exponential fit for aprotic solvents and bi-exponential fit for protic solvents (EtOH and MeOH). Compared to the curcumin ligand (1), the metal complexes (1a-b) exhibited higher singlet oxygen quantum yields (ΦΔ = 0.36 and 0.54, respectively). The in vitro antimicrobial photoactivity of the compounds was evaluated against six different microorganisms. The results showed that the metal complexes (1a-b) exhibited both antileishmanial (MIC = 2.29 μM against Leishmania amazonensis promastigotes) and antifungal (IC50 = 10 μM against Sporothrix brasiliensis yeasts) activities, while the ligand showed no activity, suggesting the chelation with the metals Cu (II) and Pd (II) may improve its photoactivity.

Curcumin ligand based iridium(III) complexes as inhibition and visualization agent of beta-amyloid fibrillation

In this work, curcumin ligand based Ir(III) complexes are synthesized. Their applications in the inhibiting and monitoring the fibrillation of Beta-amyloid (Aβ) peptides have been investigated. Ascribed to the outstanding photophysical properties of Ir(III) complex skeleton and the abundant functional groups of curcumin ligand, the newly developed Ir(III) complexes possess excellent recognition and inhibition ability towards Aβ42 peptide aggregation. Experimental results show that these complexes can effectively inhibit and monitor Aβ42 peptide aggregation in vitro. Ir-3-cur can inhibit seed-mediated Aβ42 peptide fibrillation completely with the concentration of 50 μM. Moreover, Ir-3-cur is able to distinguish Aβ42 fibril from its monomer with 9.4-fold signal increase. These Ir(III) complexes have the potency superior to previously reported curcumin. Furthermore, the cytotoxicity of these Ir(III) complexes were also investigated, demonstrating a low toxicity and neuro-protective ability against the cytotoxicity caused by three forms of Aβ42 peptides.

Investigation of binding interaction between human serum albumin with zirconium complex of curcumin and curcumin

The current study investigates the binding process of Zr(CUR) as a novel six-coordinate complex of zirconium with curcumin ligand and curcumin (CUR); as the main pharmacologically active ingredient of turmeric to human serum albumin (HSA); using fluorescence spectroscopy, infrared spectroscopy and molecular docking techniques. The fluorimetric results revealed that Zr(CUR) and CUR could effectively quench the endogenous fluorescence of HSA, formed a 1:1 complex, with a static quenching mechanism. The distance between donor (HSA) and acceptor (Zr(CUR) and CUR) were determined to be 3.15 nm for Zr(CUR) and 2.95 nm for CUR on the basis of the Forester’s theory of non-radiative energy transfer. Results of the infrared absorption spectrum show that the secondary structure of HSA changes for both types. Molecular docking results indicated that for structure with minimum binding energy Zr(CUR) and CUR are in the position between IIA and IIIA. Also, a docking study showed that Zr(CUR) and CUR have several hydrogen bonds and Van der Waals contact with HSA. Communicated by Ramaswamy H. Sarma

Curcumin nanoemulsion as a biocompatible medium to study the metal ion imbalance in a biological system

Metal imbalance in the human body especially iron causes neurodegenerative disorder included Parkinson's disease, multiple sclerosis and Alzheimer's disease and leads to compromised antioxidant function. The metal chelator drug molecules have the ability to reduce neurodegenerative disorders. Therefore, the aim of the present study is to measure the effectiveness of curcumin ligand for the detection of metal ions i.e. Fe2+, Fe3+, Mn2+, Co2+, Cu2+, and Gd3+ in oil in water nanoemulsion (NEm). The binding of curcumin with different metal ions at 298.15, 303.15, and 308.15 K has been analyzed using fluorescence and UV–visible absorption spectroscopy. The photoluminescence emission spectrum of curcumin shows unique behavior with different metal ions. The metal ions such as Fe2+, Fe3+ and Cu2+ quenches the fluorescence intensity of curcumin whereas the metals like Mn2+, Co2+, Hg2+ and Gd3+ enhances the fluorescence intensity of curcumin. Fe2+, Fe3+ and Cu2+ display strong binding nature compared to other metal ions and bind with curcumin in the stoichiometry ratio, 1:2 (Fe2+, Fe3+/curcumin) and 1:1 (Cu2+/curcumin), respectively. Stern–Volmer plots used for the quenching mechanism depict, Fe2+ and Fe3+ quench the photoluminescence intensity of curcumin by combining static and dynamic mechanisms, whereas with Cu2+ it was found to show dynamic quenching only. All other metal ions (Mn2+, Co2+, and Gd3+) indicated weak coordination with curcumin molecules.

Synthesis of Metal–Curcumin Complex Compounds (M = Na⁺, Mg²⁺, Cu²⁺)

Curcumin complex compound, MLn (L = curcumin; M = Na+, Mg2+, Cu2+) has been synthesized from the reaction between curcumin and metal precursors (NaCl, MgSO4.7H2O, CuCl2.2H2O) in ethanol under reflux conditions. Synthesis takes place through the reaction between the metal ions Na+, Mg2+, or Cu2+ as the central atom and curcumin as the ligand. Curcumin has been consumed after the reaction lasts for four hours, shown by thin-layer chromatography in which a new spot appears at higher Rf as the spot of curcumin disappears in the reaction mixture. Compared with the spectrum of curcumin, the FTIR spectra of the complexes show changes in the absorption bands and shifts of wave numbers particularly in absorption bands of phenolic –OH and C=O enol groups which strongly indicates the coordination of metal ions with the curcumin ligand which is proposed to be in β–1,3 diketone system. Also, the FTIR spectra of the reaction product showed typical absorption bands for the metal-oxygen group, M–O, at 524 cm–1, 670 cm–1 and 470 cm–1 in Na+–curcumin, Mg2+–curcumin and Cu2+–curcumin, respectively.

Kurkumin demir(III) kompleksinin demir şelasyonunun in vitro etkileri

urpose: The aim of this study was to investigate the cytotoxicity effect, iron chelator and antioxidant activities of iron (III) ions with curcumin ligand that may be used in the treatment of iron overload. Materials and Methods: The cytotoxic activities of the ligand and the complex were evaluated by the MTT assay. The SOD activity of the complex of curcumin was determined by using its ability to inhibit the reduction of NBT. The catalytic activity studies of Fe(III) complex in DMSO towards the disproportionation of hydrogen peroxide were also performed.Results: The IC50 values are found in 6.8 μM catalase activity was measured. Where at a concentration of 2.0 mM, the activity was equivalent to 183.30 U/L. The complex shows a catalase activity. The complex showed minimal toxicity. IC50 values found 5.3 mg/ml. The observed cytotoxicity could be pursued to obtain a potential drug. The iron chelator effects were determined by Ferrozine reagent. Curcumin, the most active extract interfered with the formation of ferrous and ferrozine complex. It demonstrated strong chelating activities. The result showed that the complexes possess considerable SOD activity. This finding indicates that the iron complex is capable of removing free radicals. Conclusion: The study results revealed that the iron(III) complex of curcumin with an appropriate potential drug may act as a protector against oxidative stress. Therefore, all results suggest that curcumin may represent a new approach in the treatment of iron overload.

Novel uranyl-curcumin-MOF photocatalysts with highly performance photocatalytic activity toward the degradation of phenol red from aqueous solution: effective synthesis route, design and a controllable systematic study

In this work, the uranyl-curcumin metal–organic framework (MOF) samples were synthesized using ultrasound, reflux, hydrothermal and ultrasound assisted reflux techniques. Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and N2 adsorption/desorption isotherm were used to identify and investigate the properties of the samples. The results showed that the synthesized products by ultrasound methods shows excellent properties than the other methods and had a significant porosity of 2.74 nm with the surface area of 42.66 m2/g. In this method, the size of particles is in the range of 40–90 nm, and the samples had a spherical morphology by uniform distribution without any agglomeration. In the second part of this study, the 2k−1 factorial method was used to evaluate the effects of several parameters (pH, contact time, phenol red concentration and photocatalyst content) on the photocatalytic activity of the uranyl-MOF with curcumin ligands in the degradation of phenol red from aqueous samples. The results showed that in optimal conditions (pH 8.04, contact time: 11 min, phenol red concentration: 0.11 mg/L, and amount of MOF: 18.00 mg), more than 99% of the phenol red could be degraded.

Synthesis, characterization and electrochemistry studies of iron(III) complex with curcumin ligand

Iron overload is a serious clinical condition for humans and is a key target in drug development. The aim of this study was to investigate the coordination of iron(III) ions with curcumin ligand that may be used in the treatment of iron overload. Iron(III) complex of curcumin was synthesized and structurally characterized in its solid and solution state by FT-IR, UV-Vis, elemental analysis, and magnetic susceptibility. Electrochemical behaviour of the ligand and the complexes were examined using cyclic voltammetry. The cytotoxic activities of the ligand and the iron(III) complex were evaluated by the MTT assay. Curcumin reacted with iron in high concentrations at physiological pH at room temperature. Subsequently, a brown-red complex was formed. Data regarding magnetic susceptibility showed that the complexes with a 1:2 (metal/ligand) mole ratio had octahedral geometry. The complex showed higher anti-oxidant effect towards the cell line ECV304 at IC50 values of 4.83 compared to curcumin. The complex exhibited very high cytotoxic activity and showed a cytotoxic effect that was much better than that of the ligand. The potentials for redox were calculated as 0.180V and 0.350V, respectively. The electrochemistry studies showed that Fe3+ /Fe2+ couple redox process occurred at low potentials. This value was within the range of compounds that are expected to show superoxide dismutase activity. This finding indicates that the iron complex is capable of removing free radicals. The observed cytotoxicity could be pursued to obtain a potential drug. Further studies investigating the use of curcumin for this purpose are needed.

Curcumin "Drug" Stabilized in Oxidovanadium(IV)-BODIPY Conjugates for Mitochondria-Targeted Photocytotoxicity.

Ternary oxidovanadium(IV) complexes of curcumin (Hcur), dipicolylamine (dpa) base, and its derivatives having pendant noniodinated and di-iodinated boron-dipyrromethene (BODIPY) moiety (L1 and L2, respectively), namely, [VO(dpa)(cur)]ClO4 (1), [VO(L1)(cur)]ClO4 (2), and [VO(L2)(cur)]ClO4 (3) and their chloride salts (1a-3a) were prepared, characterized, and studied for anticancer activity. The chloride salts were used for biological studies due to their aqueous solubility. Complex 1 was structurally characterized by single-crystal X-ray crystallography. The complex has a VO2+ moiety bound to dpa ligand showing N,N,N-coordination in a facial mode, and curcumin is bound in its mono-anionic enolic form. The V-O(cur) distances are 1.950(18) and 1.977(16) Å, while the V-N bond lengths are 2.090(2), 2.130(2), and 2.290(2) Å. The bond trans to V═O is long due to trans effect. The complexes are stable in a solution phase over a long period of time of 48 h without showing any apparent degradation of the curcumin ligand. The diiodo-BODIPY ligand (L2) or Hcur alone showed limited solution stability in dark. The emissive BODIPY (L1) containing complex 2a showed preferential mitochondrial localization in MCF-7 cells in cellular imaging experiments. The cytotoxicity of the complexes was studied by MTT assay. The BODIPY complex 3a showed excellent photodynamic therapy effect in visible light (400-700 nm) giving IC50 values of 2-6 μM in HeLa and MCF-7 cancer cells, while being less toxic in dark (∼100 μM). The cell death was apoptotic in nature involving reactive oxygen species (ROS). Mechanistic data from pUC19 DNA photocleavage studies revealed photogenerated ROS as primarily 1O2 from the BODIPY moiety and ·OH radicals from the curcumin ligand.

Dicationic Ruthenium(II)–Arene–Curcumin Complexes Containing Methylated 1,3,5‐Triaza‐7‐phosphaadamantane: Synthesis, Structure, and Cytotoxicity

Dicationic ruthenium(II)–p‐cymene complexes containing curcumin ligands (curcH = curcumin, bdcurcH = bisdemethoxycurcumin) and ionic N‐methyl‐1,3,5‐triaza‐7‐phosphaadamantane [PTA‐Me]X (X = BF4 or I) have been synthesized and fully characterized for the first time. The solid‐state structure of [Ru(p‐cym)(curc)(PTA‐Me)][SO3CF3][BF4] has also been determined by single‐crystal X‐ray diffraction. Modest antiproliferative activities of the complexes were observed against cisplatin‐sensitive and cisplatin‐resistant human ovarian carcinoma cells (A2780 and A2780cisR, respectively) and nontumorigenic human embryonic kidney (HEK293) cells.

Multifunctional LUV liposomes decorated for BBB and amyloid targeting - B. In vivo brain targeting potential in wild-type and APP/PS1 mice

Multifunctional liposomes (mf-LIPs) having a curcumin-lipid ligand (to target amyloids) together with two ligands to target the transferrin, and the low-density apolipoprotein receptor of the blood-brain-barrier (BBB) on their surface, were previously studied (in vitro) as potential theranostic systems for Alzheimer's disease (AD) (Papadia et al., 2017, Eur. J. Pharm. Sciences; 101:140–148). Herein, the targeting potential of mf-LIPs was compared to that of BBB-LIPs (liposomes having only the two BBB-specific ligands) in FVB mice (normal), as well as in double transgenic mice (APP/PS1) and their corresponding littermates (WT), by live-animal (in vivo) and explanted organ (ex vivo) imaging. In FVB mice, the head-signals of mf-LIPs and BBB-LIPs are either similar, or signals from mf-LIP are higher, suggesting that the co-presence of the curcumin derivative on the liposome surface does not disturb the functionality of the BBB-specific ligands. Higher brain/liver+spleen ratios (ex vivo) were calculated post-injection of mf-LIP, compared to those found after BBB-LIP injection, due to the reduced distribution of mf-LIPs in the liver and spleen; showing that the curcumin ligand increases the stealth properties of liposomes by reducing their uptake by liver and spleen. The later effect is more pronounced when the density of the BBB-specific ligands on the mf-LIPs is 0.1mol%, compared to 0.2%, highlighting the importance of this parameter. When a high lipid dose (4mg/mouse) is injected in WT and APP/PS1 mice, the head-signals of mf-LIPs are significantly higher than those of BBB-LIPs, but no differences are observed between WT and APP/PS1 mice. However, after administration of a low liposome dose (0.05mg/mouse) of mf-LIPs, significant differences in the head-signals are found between WT and transgenic mice, highlighting the AD theranostic potential of the multifunctional liposomes, as well as the importance of the experimental parameters used in such in vivo screening studies.

Synthesis and in vitro Toxicity of d‐Glucose and d‐Fructose Conjugated Curcumin–Ruthenium Complexes

A series of carbohydrate‐conjugated bis(demethoxy)curcumin (BDC) ligands were synthesized by using the Huisgen copper(I)‐catalyzed cycloaddition between azido‐functionalized d‐glucose and d‐fructose as well as propargyl‐modified BDC. The unprotected sugar ligands were treated with Ru(bpy)2Cl2 to form curcumin‐conjugated Ru complexes of general formula Ru(bpy)2(L)Cl. The ligands as well as Ru complexes were analyzed by NMR, IR, UV/Vis, and fluorescence spectroscopy, mass spectrometry as well as by elemental analysis (EA). Incubation of L929, HepG2 and the breast cancer cell line MDA‐MB‐231 revealed lower cytotoxicity of all carbohydrate‐conjugated ligands compared with BDC. The Ru complexes exhibited higher cytotoxicity than the parent ligands, in particular against HepG2 cells, whereas the noncancerous L929 cell line remained unaffected. Unexpectedly, the d‐fructose‐conjugated ligand and its corresponding Ru complex did not show any significant toxicity against MDA‐MB‐231 cells.

A systems biology approach for elucidating the interaction of curcumin with Fanconi anemia FANC G protein and the key disease targets of leukemia

Fanconi anemia (FA) is an autosomal recessive disorder with a high risk of malignancies including acute myeloid leukemia and squamous cell carcinoma. There is a constant search out of new potential therapeutic molecule to combat this disorder. In most cases, patients with FA develop haematological malignancies with acute myeloid leukemia and acute lymphoblastic leukemia. Identifying drugs which can efficiently block the pathways of both these disorders can be an ideal and novel strategy to treat FA. The curcumin, a natural compound obtained from turmeric is an interesting therapeutic molecule as it has been reported in the literature to combat both FA as well as leukemia. However, its complete mechanism is not elucidated. Herein, a systems biology approach for elucidating the therapeutic potential of curcumin against FA and leukemia is investigated by analyzing the computational molecular interactions of curcumin ligand with FANC G of FA and seven other key disease targets of leukemia. The proteins namely DOT1L, farnesyl transferase (FDPS), histone decetylase (EP3000), Polo-like kinase (PLK-2), aurora-like kinase (AUKRB), tyrosine kinase (ABL1), and retinoic acid receptor alpha (RARA) were chosen as disease targets for leukemia and modeled structure of FANC G protein as the disease target for FA. The docking investigations showed that curcumin had a very high binding affinity of −8.1 kcal/mol with FANC G protein. The key disease targets of leukemia namely tyrosine kinase (ABL1), aurora-like kinase (AUKRB), and polo-like kinase (PLK-2) showed that they had the comparable binding affinities of −9.7 k cal/mol, −8.7 k cal/mol, and −8.6 k cal/mol, respectively with curcumin. Further, the percentage similarity scores obtained from PAM50 using EMBOSS MATCHER was shown to provide a clue to understand the structural relationships to an extent and to predict the binding affinity. This investigation shows that curcumin effectively interacts with the disease targets of both FA and leukemia.

Application of trans-[ZrO(curcumin)2(H2O)]·H2O in coloration of cotton fibers

A novel six-coordinate complex of Zr(IV) with curcumin ligand was synthesized and characterized by thermogravimetric analysis, elemental analysis and spectroscopic techniques. 1HNMR and 13CNMR spectra showed that two curcumin ligands behave as a bidentate monobasic ligand and occupy trans- positions, while two other remaining coordination sites of zirconium are occupied by O and H2O. The complex was screened for antibacterial activity and showed no inhibitory effect against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Salmonella enteritidis. Eventually it was found that the complex can be used as a non-toxic, stable and exotic orange dye in coloration of cotton fibers.