RESUMO
Ethylene dimerization is an efficient industrial chemical process to produce 1-butene, with demanding selectivity and activity requirements on new catalytic systems. Herein, a series of monodentate phosphinoamine-nickel complexes immobilized on UiO-66 are described for ethylene dimerization. These catalysts display extensive molecular tunability of the ligand similar to organometallic catalysis, while maintaining the high stability attributed to the metal-organic framework (MOF) scaffold. The highly flexible postsynthetic modification method enables this study to prepare MOFs functionalized with five different substituted phosphines and 3 N-containing ligands and identify the optimal catalyst UiO-66-L5-NiCl2 with isopropyl substituted nickel mono-phosphinoamine complex. This catalyst shows a remarkable activity and selectivity with a TOF of 29 000 (molethyl/molNi/h) and 99% selectivity for 1-butene under ethylene pressure of 15 bar. The catalyst is also applicable for continuous production in the packed column micro-reactor with a TON of 72 000 (molethyl/molNi). The mechanistic insight for the ethylene oligomerization has been examined by density functional theory (DFT) calculations. The calculated energy profiles for homogeneous complexes and truncated MOF models reveal varying rate-determining step as ß-hydrogen elimination and migratory insertion, respectively. The activation barrier of UiO-66-L5-NiCl2 is lower than other systems, possibly due to the restriction effect caused by clusters and ligands. A comprehensive analysis of the structural parameters of catalysts shows that the cone angle as steric descriptor and butene desorption energy as thermodynamic descriptor can be applied to estimate the reactivity turnover frequency (TOF) with the optimum for UiO-66-L5-NiCl2. This work represents the systematic optimization of ligand effect through combination of experimental and theoretical data and presents a proof-of-concept for ethylene dimerization catalyst through simple heterogenization of organometallic catalyst on MOF.
RESUMO
In this work, we demonstrate a simple sol-gel technique to prepare metal-ion(s)-doped ceria-zirconia solid solution for efficient catalytic methane activation. The cation-depicting formula units are Ce0.80Zr0.20 (CZ), Ce0.79Zr0.20M0.01 (CZM), and Ce0.79Zr0.20M0.005M10.005 (CZMM1) (M and M1 = V, Mn, Fe, Co, and Cu), employed for undoped, mono-metal-ion-doped, and bi-metal-ion-doped solid solutions, respectively. Methane activation with Mn, Fe, Cu mono-metal-ion-doped CZ favors the C1 product, while CZCo assists C-C coupling with the formation of acetaldehyde. On the other hand, the Co- and Fe-doped bi-metal-ion combination catalyst (CZCoFe) shows significant ethanol but predominant formic acid formation. This is further promoted by the Co + V bi-metal-ion combination (CZCoV) catalyst, and it shows ethanol as the major product along with methyl hydrogen peroxide, methanol, and formic acid as minor products. An impressive ethanol yield of 93 µmol/g h with 76% selectivity obtained with the CZCoV catalyst is at par with that obtained with noble-metal-based catalysts under comparable reaction conditions. When Co and V content was increased two and four times from 0.005 to 0.01 and 0.02, ethanol yield increased at the expense of formic acid. The 213 µmol/g h ethanol yield (86% selectivity) observed with Ce0.76Zr0.20Co0.02V0.02 is probably the highest observed. The partial oxidation of CH4 in Co-based bi-metal combinations (Co + V or Co + Fe) suggests the synergistic effect of doped metal ions owing to the heterogeneous near-neighbor environment. The present results are attributed to the surface heterogeneity between the host and the dopants, which selectively promotes methane activation as well as C-C coupling. This indicates a large scope to tune the activity of partial oxidation of methane and product selectivity with different metal-ion(s) combinations.
RESUMO
The pandemic respiratory disease COVID-19 has spread over the globe within a small span of time. Generally, there are two important points are being highlighted and considered towards the successful diagnosis and treatment process. The first point includes the reduction of the rate of infections and the next one is the decrease of the death rate. The major threat to public health globally progresses due to the absence of effective medication and widely accepted immunization for the COVID-19. Whereas, understanding of host susceptibility, clinical features, adaptation of COVID-19 to new environments, asymptomatic infection is difficult and challenging. Therefore, a rapid and an exact determination of pathogenic viruses play an important role in deciding treatments and preventing pandemic to save the people's lives. It is urgent to fix a standardized diagnostic approach for detecting the COVID-19. Here, this systematic review describes all the current approaches using for screening and diagnosing the COVID-19 infectious patient. The renaissance in pathogen due to host adaptability and new region, facing creates several obstacles in diagnosis, drug, and vaccine development process. The study shows that adaptation of accurate and affordable diagnostic tools based on candidate biomarkers using sensor and digital medicine technology can deliver effective diagnosis services at the mass level. Better prospects of public health management rely on diagnosis with high specificity and cost-effective manner along with multidisciplinary research, specific policy, and technology adaptation. The proposed healthcare model with defined road map represents effective prognosis system.
RESUMO
Green hydrogen presents itself as a clean energy vector, which can be produced by electrolysis of water by utilizing renewable energy such as solar or wind. While current technologies are sufficient to support commercial deployment of fresh water electrolyzers, there remain a few well-defined challenges in the path of commercializing direct seawater electrolyzers, predominantly related to the sluggish oxygen evolution reaction (OER) kinetics and the competing chlorine evolution reaction (CER) at the anode. Herein, we report the facile and swift fabrication of an S,B-codoped CoFe oxyhydroxide via solution combustion synthesis for the OER with apparent CER suppression abilities. The as-prepared S,B-(CoFe)OOH-H attained ultralow overpotentials of 161 and 278 mV for achieving current densities of 10 and 1000 mA cm-2, respectively, in an alkaline saline (1 M KOH + 0.5 M NaCl) electrolyte, with a low Tafel slope of 46.7 mV dec-1. Chronoamperometry testing of the codoped bimetallic oxyhydroxides showed very stable behavior in harsh alkaline saline and in neutral pH saline environments. S,B-(CoFe)OOH-H oxyhydroxide showed a notable decrease in CER production in comparison to the other S,B-codoped counterparts. Selectivity measurements through online FE calculations showed high OER selectivity in alkaline (FE â¼ 97%) and neutral (FE â¼ 91%) pH saline conditions under standard 10 mA cm-2 operation. Moreover, systematic testing in electrolytes at pH values of 14 to 7 yielded promising results, thus bringing direct seawater electrolysis at near-neutral pH conditions closer to realization.
RESUMO
Using abundant seawater can reduce reliance on freshwater resources for hydrogen production from electrocatalytic water splitting. However, seawater has detrimental effects on the stability and activity of the hydrogen evolution reaction (HER) electrocatalysts under different pH conditions. In this work, we report the synthesis of binary metallic core-sheath nitride@oxynitride electrocatalysts [Ni(ETM)]δ+-[O-N]δ-, where ETM is an early transition metal V or Cr. Using NiVN on a nickel foam (NF) substrate, we demonstrate an HER overpotential as low as 32 mV at -10 mA cm-2 in saline water (0.6 M NaCl). The results represent an advancement in saline water HER performance of earth-abundant electrocatalysts, especially under near-neutral pH range (i.e., pH 6-8). Doping ETMs in nickel oxynitrides accelerates the typically rate-determining H2O dissociation step for HER and suppresses chloride deactivation of the catalyst in neutral-pH saline water. Heterointerface synergism occurs through H2O adsorption and dissociation at interfacial oxide character, while adsorbed H* proceeds via Heyrovsky or Tafel step on the nitride character. This electrocatalyst showed stable performance under a constant current density of -50 mA cm-2 for 50 h followed by additional 50 h at -100 mA cm-2 in a neutral saline electrolyte (1 M PB + 0.6 M NaCl). Contrarily, under the same conditions, Pt/C@NF exhibited significantly low performance after a mere 4 h at -50 mA cm-2. The low Tafel slope of 25 mV dec-1 indicated that the reaction is Tafel limited, unlike commercial Pt/C, which is Heyrovsky limited. We close by discussing general principles concerning surface charge delocalization for the design of HER electrocatalysts in pH saline environments.
RESUMO
Catalytic methane decomposition (CMD) is a highly promising approach for the rational production of relatively COx-free hydrogen and carbon nanostructures, which are both important in multidisciplinary catalytic applications, electronics, fuel cells, etc. Research on CMD has been expanding in recent years with more than 2000 studies in the last five years alone. It is therefore a daunting task to provide a timely update on recent advances in the CMD process, related catalysis, kinetics, and reaction products. This mini-review emphasizes recent studies on the CMD process investigating self-standing/supported metal-based catalysts (e.g., Fe, Ni, Co, and Cu), metal oxide supports (e.g., SiO2, Al2O3, and TiO2), and carbon-based catalysts (e.g., carbon blacks, carbon nanotubes, and activated carbons) alongside their parameters supported with various examples, schematics, and comparison tables. In addition, the review examines the effect of a catalyst's shape and composition on CMD activity, stability, and products. It also attempts to bridge the gap between research and practical utilization of the CMD process and its future prospects.
RESUMO
A new N-oxide, Pseudolycorine N-oxide (1) was characterised along with eleven known alkaloids homolycorine (2), O-methylmaritidine (3), 8-O-demethylhomolycorine (4), homolycorine N-oxide (5), lycorine (6), narciclasine (7), pseudolycorine (8), ungeremine (9), 8-O-demethylmaritidine (10), zefbetaine (11) and lycorine N-oxide (12), from Narcissus tazetta. Their structures were established on the basis of spectroscopic data analysis. The extract, fractions and isolated compounds were screened for in vitro cytotoxicity against two human cancer cell lines, human cervical cancer (SiHa) and human epidermoid carcinoma (KB) cells. The study demonstrated the cytotoxic potential of extract and its chloroform and n-butanol fractions. Further, the results revealed the bioactive potential of narciclasine, pseudolycorine and homolycorine alkaloids. However, new N-oxide (1) was not active against these cell lines.
Assuntos
Alcaloides/isolamento & purificação , Alcaloides de Amaryllidaceae/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Narcissus/química , Óxidos/isolamento & purificação , Fenantridinas/isolamento & purificação , Extratos Vegetais/química , Alcaloides/química , Alcaloides de Amaryllidaceae/análise , Alcaloides de Amaryllidaceae/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Indolizinas/análise , Óxidos/química , Fenantridinas/análise , Fenantridinas/químicaRESUMO
A new narciclasine glycoside, narciclasine-4-O-ß-D-xylopyranoside (1) was characterised along with four known alkaloids pancratistatin (2), 1-O-(3-hydroxybutyryl) pancratistatin (3), vittatine (4), 9-O-demethylgalanthine (5) from Zephyranthes minuta. Their structures were established on the basis of spectroscopic data analysis. The in vitro cytotoxic study of extract, fractions and isolated compounds against two human cancer cell lines (KB and SiHa) indicated the potential activity of extract and n-butanol fraction due to presence of active alkaloids pancratistatin, 1-O-(3-hydroxybutyryl) pancratistatin, lycorine and haemanthamine.
Assuntos
Alcaloides de Amaryllidaceae/isolamento & purificação , Amaryllidaceae/química , Glicosídeos/isolamento & purificação , Fenantridinas/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacologia , Glicosídeos Cardíacos , Linhagem Celular Tumoral , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Glicosídeos/química , Humanos , Isoquinolinas/farmacologia , Fenantridinas/química , Fenantridinas/farmacologia , Extratos Vegetais/químicaRESUMO
Fatigue is a dominant failure mechanism of several engineering components. One technique for increasing the fatigue life is by inducing surface residual stress to inhibit crack initiation. In this review, a microstructural study under various bulk (such as severe plastic deformation) and surface mechanical treatments is detailed. The effect of individual microstructural feature, residual stress, and strain hardening on mechanical properties and fatigue crack mechanisms are discussed in detail with a focus on nickel-based superalloys. Attention is given to the gradient microstructure and interface boundary behavior for the mechanical performance. It is recommended that hybrid processes, such as shot peening (SP) followed by deep cold rolling (DCR), could enhance fatigue life. The technical and scientific understanding of microstructural features delineated here could be useful for developing materials for fatigue performance.
RESUMO
BACKGROUND: Epidermal growth factor receptor (EGFR) inhibitors are an extensively utilized class of chemotherapeutic agents which form an integral component of treatment in solid organ malignancies such as non-small-cell lung carcinoma, pancreatic carcinoma, colorectal carcinoma, and head and neck carcinoma. It has two subclasses: epidermal growth factor inhibitors (erlotinib) and monoclonal antibody (cetuximab). A wide array of cutaneous adverse effects has been attributed to this class of drugs, such as papulopustular eruptions, paronychia, xerosis, and changes in hair and nails. MATERIALS AND METHODS: A total of 76 cases of various malignancies on EGFR inhibitors who developed cutaneous side effects while on therapy and reported or referred to us by oncologists from January 2017 to January 2018 were included in the study. All the patients who were on other associated medications or radiotherapy were excluded. RESULT: In all, 45 (59.2%) were males and 31 (40.7%) were females. Non-small-cell lung carcinoma was the most common carcinoma in 32 (42.1%) patients, and cetuximab was the most common drug in 29 (38.1%) cases. Papulopustular eruptions were seen in 61 (80.2%) patients, xerosis in 31 (40.7%), mucositis in 6 (7.8%), hair growth problems in 4 (5.6%), and paronychia and pyogenic granuloma in 2 (2.6%) patients each. CONCLUSION: Although most of the skin toxicities associated with EGFR inhibitors can be managed conservatively, a critical analysis of the cases that are significantly affected due to these side effects is required in cohesion with the treating oncologist to improve the therapeutic compliance of the drug.
RESUMO
Needles of seven cultivated clones (C1 - C7) of Juniperus communis at lower altitude and three wild Juniperus species (J. communis, J. recurva and J. indica) at higher altitudes were investigated comparatively for their essential oils (EOs) yields, chemical composition, cytotoxic and antibacterial activities. The EOs yields varied from 0.26 to 0.56% (v/w) among samples. Sixty-one volatile components were identified by gas chromatography-mass spectrometry (GC/MS) and quantified using gas chromatography GC (FID) representing 82.5 - 95.7% of the total oil. Monoterpene hydrocarbons (49.1 - 82.8%) dominated in all samples (α-pinene, limonene and sabinene as major components). Principal component analysis (PCA) of GC data revealed that wild and cultivated Juniperus species are highly distinct due to variation in chemical composition. J. communis (wild species) displayed cytotoxicity against SiHa (human cervical cancer), A549 (human lung carcinoma) and A431 (human skin carcinoma) cells (66.4 ± 2.2%, 74.4 ± 1.4% and 57.4 ± 4.0%), respectively, at 200 µg/ml. EOs exhibited better antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria with the highest zone of inhibition against Staphylococcus aureus MTCC 96 (19.2 ± 0.7) by clone-7. As per the conclusion of the findings, EOs of clone-2, clone-5 and clone-7 can be suggested to the growers of lower altitude, as there is more possibility of uses of these EOs in food and medicinal preparations.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Juniperus/química , Micrococcus luteus/efeitos dos fármacos , Óleos Voláteis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Clonagem Molecular , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Sementes/química , Sementes/genética , Especificidade da Espécie , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
BACKGROUND: Established predictive biomarkers for Non-Small Cell Lung Carcinoma (NSCLC) include sensitizing Epidermal Growth Factor Receptor (EGFR) mutations and Anaplastic Lymphoma Kinase (ALK) fusion oncogene. The primary aim of the study is to ascertain the prevalence of EGFR mutation and ALK gene rearrangement in patients of lung adenocarcinoma in Indian population and the second objective is to impress upon the importance of adequate processing of limited tissue samples. METHODS: Histopathologically confirmed cases of lung adenocarcinoma, whose tumour had been tested for both EGFR and ALK gene mutations, were included in this study. The EGFR mutations were analyzed using PCR and Gene Sequencing. ALK fusion oncogene was found by Fluorescence In Situ Hybridization (FISH) technique using kit of Vysis LSI ALK Dual colour Break Apart Rearrangement probe. RESULTS: A total of 152 cases of lung adenocarcinoma were included. Out of which, 92 (60.5%) were male and 60 (39.5%) were female. After exclusion of 17 cases due to unsatisfactory result, EGFR mutations were found positive in 35.5% cases (48/135). ALK gene rearrangement was found in 7.6% (10/131) after excluding 21 cases with unsatisfactory result. CONCLUSION: EGFR mutations and ALK gene rearrangement was found to be mutually exclusive. Incidence of EGFR mutations (35.5%) is much higher in Indian population than in Caucasians (13%) and is close to the incidence in East Asian countries. The 7.6% incidence of ALK fusion oncogene in Indian patients establishes the importance of molecular studies to give maximum benefit of targeted therapy to the patients.
RESUMO
Purple coloured tea shoot clones have gained interest due to high content of anthocyanins in addition to catechins. Transcript expression of genes encoding anthocyanidin reductase (ANR), dihydroflavonol-4-reductase (DFR), anthocyanidin synthase (ANS), flavonol synthase (FLS) and leucoantho cyanidin reductase (LAR) enzymes in three new purple shoot tea clones compared with normal tea clone showed higher expression of CsDFR, CsANR, CsANS and lower expression of CsFLS and CsLAR in purple shoot clones compared to normal clone. Expression pattern supported high content of anthocyanins in purple tea. Four anthocyanins (AN1-4) were isolated and characterized by UPLC-ESI-QToF-MS/MS from IHBT 269 clone which recorded highest total anthocyanins content. Cyanidin-3-O-ß-d-(6-(E)-coumaroyl) glucopyranoside (AN2) showed highest in vitro antioxidant activity (IC50 DPPH = 25.27 ± 0.02 µg/mL and IC50 ABTS = 10.71 ± 0.01 µg/mL). Anticancer and immunostimulatory activities of cyanidin-3-glucoside (AN1), cyanidin-3-O-ß-d-(6-(E)-coumaroyl) glucopyranoside (AN2), delphinidin-3-O-ß-d-(6-(E)-coumaroyl) glucopyranoside (AN3), cyanidin-3-O-(2-O-ß-xylopyranosyl-6-O-acetyl)-ß-glucopyranoside (AN4) and crude anthocyanin extract (AN5) showed high therapeutic perspective. Anthocyanins AN1-4 and crude extract AN5 showed cytotoxicity on C-6 cancer cells and high relative fluorescence units (RFU) at 200 µg/mL suggesting promising apoptosis induction activity as well as influential immunostimulatory potential. Observations demonstrate potential of purple anthocyanins enriched tea clone for exploitation as a nutraceutical product.
RESUMO
Picroliv, a mixture of picroside I and kutkoside isolated from rhizome of Picrorrhiza kurroa has been reported for many pharmaceutical properties such as hepatoprotective, anticholestatic, antioxidant and immune-modulating activity. However, picroliv possessed lesser efficacy due to its poor aqueous solubility and lesser bioavailability. To find solution, picroliv was loaded into biodegradable poly lactic acid nanoparticles (PLA NPs) using solvent evaporation method. The picroliv-loaded PLA NPs were characterised by UV-vis spectroscopy, atomic force microscopy, transmission electron microscopy, Fourier transform infrared and Zeta sizer. The size of picroliv-loaded PLA NPs was 182 ± 20 nm. Zeta potential of picroliv-loaded PLA NPs was -23.5 mV, indicated their good stability. In vitro picroliv release from picroliv-loaded PLA NPs showed an initial burst release followed by slow and sustained release. The efficacy of picroliv-loaded PLA NPs was assessed against KB cell lines. Blank PLA NPs showed no cytotoxicity on KB cells. The picroliv-loaded PLA NPs showed more cytotoxic activity on KB cells as compared to the pure drug. Hence, the developed picroliv nanoformulation would find potential application in pharma-sector.
Assuntos
Cinamatos/química , Cinamatos/farmacocinética , Portadores de Fármacos/química , Glicosídeos/química , Glicosídeos/farmacocinética , Nanopartículas/química , Picrorhiza/química , Ácido Vanílico/química , Ácido Vanílico/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Cinamatos/isolamento & purificação , Cinamatos/toxicidade , Portadores de Fármacos/toxicidade , Glicosídeos/isolamento & purificação , Glicosídeos/toxicidade , Humanos , Células KB , Ácido Láctico/química , Ácido Láctico/toxicidade , Nanopartículas/toxicidade , Poliésteres , Polímeros/química , Polímeros/toxicidade , Ácido Vanílico/isolamento & purificação , Ácido Vanílico/toxicidadeRESUMO
OBJECTIVES: Betulin (BT) is an abundant triterpene found predominantly in the bark of Himalayan birch. It is difficult to deliver it in vivo because of its low aqueous solubility. We have therefore developed novel formulations of BT for improving its solubility, bioavailability and therapeutic efficacy. RESULTS: Poly-D,L-lactide nanovectors (PLA NVs) were synthesized using poly(vinyl alcohol) and Lonicera japonica leaf extract (LE) as a stabiliser and named as PLA-1 NVs and PLA-2 NVs. PLA-1 NVs and PLA-2 NVs were used for the encapsulation of betulin (BT) and named as BT-En-1 and BT-En-2 NVs. The encapsulation efficiency of BT-En-1 and BT-En-2 NVs were 99.3 and 100 % respectively. Prepared nanoformulations were physically stable. An in vitro study revealed 45 % BT was released over 24 h. BT had a prolonged release from BT-En-2 NVs as compared to BT-En-1 NVs. BT-En-2 NVs had better anticancerous activity against SiHa cells than BT-En-1 NVs. CONCLUSIONS: Developed BT-EN-2 NVs had better biocompatibility, excellent stability and enhanced release characteristics than BT-En-1 NVs.
Assuntos
Antineoplásicos/metabolismo , Ácido Láctico/metabolismo , Lonicera/química , Nanopartículas/metabolismo , Extratos Vegetais/metabolismo , Folhas de Planta/química , Polímeros/metabolismo , Triterpenos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Humanos , Poliésteres , Álcool de Polivinil/metabolismoRESUMO
BACKGROUND: Plant-based traditional system of medicine continues to play an important role in healthcare. In order to find new potent source of bioactive molecules, we studied the cytotoxic activity of the essential oils from the flowers and leaves of Callistemon citrinus. This is the first report on anticancer potential of essential oils of C. citrinus. METHODS: Cytotoxicity of essential oil was evaluated using sulfo-rhodamine B (SRB) assay against human lung carcinoma (A549), rat glioma (C-6), human colon cancer (Colo-205) and human cervical cancer (SiHa) cells. Apoptosis induction was evaluated by caspase-3/7 activity which was further confirmed by western blotting. Percentage cell apoptosis was determined by Annexin V based dead cell assay followed by DNA content as cell cycle analysis against A549 and C-6 cells. While 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to check the toxicity against normal human peripheral blood mononuclear cells (PBMCs), the immunomodulatory activity on mouse splenocytes was evaluated using SRB assay. RESULTS: The GC and GC-MS analysis of these essential oils revealed high content of α-pinene (32.3%), limonene (13.1%) and α-terpineol (14.6%) in leaf sample, whereas the flower oil was dominated by 1,8-cineole (36.6%) followed by α-pinene (29.7%). The leaf oil contained higher amount of monoterpene hydrocarbons (52.1%) and sesquiterpenoids (14%) as compared to flower oil (44.6% and 1.2%, respectively). However, the flower oil was predominant in oxygenated monoterpenes (43.5%). Although both leaf and flower oils showed highest cytotoxicity on A549 cells (61.4%±5.0 and 66.7%±2.2, respectively), only 100 µg/mL flower oil was significantly active against C-6 cells (69.1%±3.1). Interestingly, no toxicity was recorded on normal cells. CONCLUSION: Higher concentration of 1,8-cineole and/or synergistic effect of the overall composition were probably responsible for the efficacy of flower and leaf oils against the tested cells. These oils may form potential source of natural anti-cancer compounds and play important role in human health.
Assuntos
Antineoplásicos/farmacologia , Flores/química , Myrtaceae/química , Óleos Voláteis/farmacologia , Folhas de Planta/química , Animais , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Quinases Ciclina-Dependentes/metabolismo , Ativação Enzimática/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imunomodulação/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Camundongos , Óleos Voláteis/toxicidade , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Baço/efeitos dos fármacos , Baço/imunologiaRESUMO
BACKGROUND: Roscoea purpurea or Roscoea procera Wall. (Zingiberaceae) is traditionally used for nutrition and in the treatment of various ailments. OBJECTIVE: Simultaneous reversed-phase high-performance liquid chromatography-ultraviolet (RP-HPLC) photodiode array detector identification of phenolic acids (PA's) was carried out in whole extract of tuber and their cytotoxic potential was estimated along with radical scavenging action. Bioactivity guided fractionation was also done to check the response potential against the same assay. MATERIALS AND METHODS: Identification and method validation was performed on RP-HPLC column and in vitro assays were used for bioactivity. RESULTS: Protocatechuic acid, syringic acid, ferulic acid, rutin, apigenin, and kaempferol were quantified as 0.774%, 0.064%, 0.265%, 1.125%, 0.128%, and 0.528%, respectively. Validated method for simultaneous determination of PA's was found to be accurate, reproducible, and linearity was observed between peak area response and concentration. Recovery of identified PA's was within the acceptable limit of 97.40-104.05%. Significant pharmacological response was observed in whole extract against in vitro cytotoxic assay, that is, Sulforhodamine B assay, however, fractionation results in decreased action potential. Similar pattern of results were observed in the antioxidant assay, as total phenolic content and total flavonoid content were highest in whole extract and decreases with fractionation. Radical scavenging activity was prominent in chloroform fraction, exhibiting IC50 at 0.25 mg/mL. CONCLUSION: Study, thus, reveals that R. purpurea exhibit significant efficacy in cytotoxic activity with the potentiality of scavenging free radicals due the presence of PA's as reported through RP-HPLC. SUMMARY: Proto-catechuic acid, syringic acid, ferulic acid, rutin, apigenin and kaempferol were quantified as 0.774, 0.064, 0.265, 1.125, 0.128 and 0.528 %Preliminary cytotoxic activity revealed that whole extract of R. purpurea exhibit promising effect and after fractionation the potentiation of action reducesThe radical scavenging potential of whole extract and fractions are well reflected by TPC, TFC and DPPH assay.