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Facile green synthesis of ZnO–CdWO4 nanoparticles and their potential as adsorbents to remove organic dye
2021
Fatima, Bushra | Siddiqui, Sharf Ilahi | Nirala, Ranjeet Kumar | Vikrant, Kumar | Kim, Ki Hyun | Ahmad, Rabia | Chaudhry, Saif Ali
In this work, ZnO–CdWO₄ nanoparticles have been synthesized by the ecofriendly green method with lemon leaf extract to favorably anchor functional groups on their surface. The prepared ZnO–CdWO₄ nanoparticles are used as adsorbent to treat Congo red (CR) dye after characterization through FT-IR, UV–Vis, TEM, SEM-EDX, and HRTEM techniques. The equilibrium partition coefficient and adsorption capacity values for CR by ZnO–CdWO₄ are estimated as 21.4 mg g⁻¹ μM⁻¹ and 5 mg g⁻¹, respectively (at an initial dye concentration of 10 mg L⁻¹). The adsorption process is found as exothermic and spontaneous, as determined by the ΔG°, ΔS°, and ΔH° values. The Boyd plot has been used as a confirmatory tool to fit the adsorption kinetics data along with intraparticle diffusion and pseudo-second-order models. Based on this research, ZnO–CdWO₄ nanoparticles are validated as an effective adsorbent for CR dye in aqueous solutions.
Show more [+] Less [-]Impact of green synthesized iron oxide nanoparticles on the distribution and transformation of As species in contaminated soil
2020
Su, Binglin | Lin, Jiajiang | Owens, Gary | Chen, Zuliang
Iron nanoparticles (Fe NPs) have often been used for in situ remediation of both groundwater and soil. However, the impact of Fe NPs on the distribution and transformation of As species in contaminated soil is still largely unknown. In this study, green iron oxide nanoparticles synthesized using a euphorbia cochinchinensis leaf extract (GION) were used to stabilize As in a contaminated soil. GION exhibited excellent As stabilization effects, where As in non-specifically-bound and specifically-bound fractions decreased by 27.1% and 67.3% after 120 days incubation. While both arsenate (As (V)) and arsenite (As (III)) decreased after GION application, As (V) remained the dominant species in soil. X-ray photoelectron spectroscopy (XPS) confirmed that As (V) was the dominant species in specifically-bound fractions, while As (III) was the dominant species in amorphous and poorly-crystalline hydrous oxides of Fe and Al. Correlation analysis showed that while highly available As fractions were negatively correlated to oxalate and DCB extractable Fe, they were positively correlated to Fe²⁺ content, which indicated that Fe cycling was the main process influencing changes in As availability. X-ray fluorescence (XRF) spectroscopy also showed that the Fe₂O₃ content increased by 47.9% following GION soil treatments. Overall, this work indicated that As would be transformed to more stable fractions during the cycling of Fe following GION application and that the application of GION, even in small doses, provides a low-cost and ecofriendly method for the stabilization of As in soil.
Show more [+] Less [-]Production of hydroxytyrosol rich extract from Olea europaea leaf with enhanced biological activity using immobilized enzyme reactors
2022
As olive leaves constitute the main by-product of the olive oil industry with important environmental and economic impact, there is an increasing demand for its valorization. In the present work, we report the development and application of immobilized enzyme batch bioreactors for the chemo-enzymatic treatment of an aqueous Olea europaea leaf extract rich in oleuropein to produce an extract enriched in hydroxytyrosol and other oleuropein hydrolysis products. To this end, a robust biocatalyst was developed through the immobilization of β-glucosidase on chitosan-coated magnetic beads which exhibited high hydrolytic stability after 240 h of incubation at 37 °C. The biocatalyst was successfully used in both a rotating bed-reactor and a stir-tank reactor for the modification of the olive leaf extract leading to high conversion yields of oleuropein (exceeding 90%), while an up to 2.5 times enrichment in hydroxytyrosol was achieved. Over 20 phenolic compounds (from different classes of phytochemicals such as flavonoids, secoiridoids, and their derivatives) were identified, in the extract before and after its modification through various chromatographic and spectroscopic techniques. Finally, the biological activity of both extracts was evaluated. Compared to the non-modified extract, the modified one demonstrated 20% higher antioxidant activity, seven-fold higher antibacterial activity, and enhanced cytotoxicity against leiomyosarcoma cells.
Show more [+] Less [-]Protective role of green tea against paraquat toxicity in Allium cepa L.: physiological, cytogenetic, biochemical, and anatomical assessment
2022
Yirmibeş, Ferhat | Yalçin, Emine | Çavuşoğlu, Kültiğin
In this study, the toxic effects of paraquat, one of the most commercially sold herbicides in the world, and the protective role of green tea leaf extract (GTLE) against these effects were investigated. Allium cepa L. bulbs (n = 16) were used as test material. One hundred milligrams per liter dose of paraquat and 190 and 380 mg/L doses of GTLE were preferred. Paraquat toxicity was investigated with the help of physiological (percent germination, root length, and weight gain), cytogenetic (mitotic index = MI, micronucleus = MN, and chromosomal damages = CAs), biochemical (superoxide dismutase = SOD, catalase = CAT, malondialdehyde = MDA), and anatomical (meristematic cell damages) parameters. A. cepa bulbs were divided into 6 groups as 1 control and 5 applications. The control group was germinated with tap water, and the application groups were germinated with paraquat and two different doses of GTLE. Germination was carried out at room temperature for 72 h. At the end of the period, A. cepa bulbs were prepared for physiological, cytogenetic, biochemical, and anatomical analyzes using routine preparation techniques. As a result, paraquat application caused a decrease in physiological parameters and an increase in cytogenetic (except MI) and biochemical parameters. Compared to the control (group I), the germination percentage decreased by 38%, root length 12.5 times, and weight gain 5 times decreased in group IV treated with paraquat. MDA level increased 2.58 times, SOD activity 2.48 times, and CAT activity 4.51 times increased. Paraquat application caused a decrease in the percentage of MI and an increase in the number of MN and CAs. Paraquat application caused CAs in the form of fragment, sticky chromosome, unequal distribution of chromatin, bridge, nucleus with vacuoles, nucleus bud, and reverse polarization. In the meristematic cells of the root tips applied paraquat, unclearly vascular tissue, flattened cell nucleus, epidermis, and cortex cell deformation were observed. The application of GTLE together with paraquat caused an increase in the physiological parameter values and a decrease in the cytogenetic (except MI) and biochemical parameter values. An improvement in the severity of damages induced by paraquat was also observed in root tip meristematic cells. It was determined that the improvements observed in all these parameters were related to the dose of GTLE applied. The 380 mg/L dose of GTLE provided more protection than the 190 mg/L dose. Compared to group IV in which paraquat was applied, the germination percentage increased by 21%, root length 5.83 times, and weight gain 2.92 times increased in group VI administered 380 mg/L dose of GTLE. In addition, MDA level decreased 1.78 times, SOD activity 1.59 times and CAT activity 1.65 times. In conclusion, paraquat administration at a dose of 100 mg/L caused physiological, cytogenetic, biochemical, and anatomical toxicity in A. cepa bulbs. GTLE application, on the other hand, resulted in improvements in the severity of this toxicity induced by paraquat, depending on the dose. Therefore, GTLE can be used as an effective nutritional supplement to reduce or prevent the toxicity caused by environmental agents such as pesticides.
Show more [+] Less [-]Investigation of Cochlospermum religiosum leaves for antidepressant and anxiolytic activities and its synergistic effect with imipramine and fluoxetine
2022
Bhatt, Shvetank | Behl, Tapan | Sehgal, Aayush | Singh, Sukhbir | Sharma, Neelam | Chigurupati, Sridevi | Ahmed, Amira Saber | Gari, Sreelakshmi Bada V.
The present study was conducted to evaluate the effect of Cochlospermum religiosum (CSR) in animal models of depression and anxiety. The CSR leaves are well known for their sedative, antibacterial, antifungal antioxidant, memory enhancing, anxiolytic and antidepressant potential. In present study, the extract of the leaves is used to relieve the anxiolytic and antidepressant potential. The leaves of CSR were investigated for antidepressant and anxiolytic activities in mice behavioural models namely, spontaneous locomotor activity (SLA), forced swim test (FST), tail suspension test (TST), elevated plus maze (EPM) and marble burying behaviour (MBB). The mechanism was supported by reserpine-induced hypothermia (RIH). Further, the in vivo synergistic evaluation of the CSR leaf extract was evaluated with imipramine and fluoxetine. The treatment of mice with ethanolic extract of CSR leaves for 7 days resulted significant antidepressant and anxiolytic effects (p < 0.05 for 50 mg/Kg p.o / p < 0.01 for 100 mg/kg p.o) with null impact on baseline locomotor activity. Further, the study on rat RIH model revealed that the CSR (50 mg/kg p.o) predominantly antagonized the effect (p < 0.05) of reserpine. Furthermore, synergic action was screened by co-administration of leaf extracts of CSR with fluoxetine (10 mg/Kg, i.p.) and imipramine (10 mg/Kg, i.p.) at below therapeutic dose levels using FST, TST, EPM and MBB. The synergistic effect was significant (p < 0.05) for both antidepressant and anxiolytic activities as compared to therapeutic doses of extract, imipramine and fluoxetine.
Show more [+] Less [-]Anti-kindling effect of Ginkgo biloba leaf extract and L-carnitine in the pentylenetetrazol model of epilepsy
2022
Essawy, Amina E. | El-Sayed, Soad Ahmed | Tousson, Ehab | Abd El-gawad, Horeya S. | Alhasani, Reem Hasaballah | Abd Elkader, Heba-Tallah Abd Elrahim
Epilepsy is one of the most common serious brain disorders, affecting about 1% of the population all over the world. Ginkgo biloba extract (GbE) and L-carnitine (LC) reportedly possess the antioxidative activity and neuroprotective potential. In this report, we investigated the possible protective and therapeutic effects of GbE and LC against pentylenetetrazol (PTZ)-induced epileptic seizures in rat hippocampus and hypothalamus. Adult male albino rats were equally divided into eight groups: control, GbE (100 mg/kg), LC (300 mg/kg), PTZ (40 mg/kg), protective groups (GbE + PTZ and LC + PTZ), and therapeutic groups (PTZ + GbE and PTZ + LC). The oxidative stress, antioxidant, and neurochemical parameters, viz., malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), acetylcholine esterase (AchE), dopamine (DA), norepinephrine (NE), and serotonin (5-HT), in the hippocampal and hypothalamic regions have been evaluated. PTZ injection leads to an increase in the seizure score, the levels of MDA and NO, and to a decrease in the activity of GSH, SOD, CAT, and GPx. Besides, monoamine neurotransmitters, DA, NE, and 5-HT, were depleted in PTZ-kindled rats. Furthermore, PTZ administration caused a significant elevation in the activity of AchE. Hippocampal and hypothalamic sections from PTZ-treated animals were characterized by severe histopathological alterations and, intensely, increased the ezrin immunolabeled astrocytes. Pre- and post-treatment of PTZ rats with GbE and LC suppressed the kindling acquisition process and remarkably alleviated all the aforementioned PTZ-induced effects. GbE and LC have potent protective and therapeutic effects against PTZ-induced kindling seizures via the amelioration of oxidative/antioxidative imbalance, neuromodulatory, and antiepileptic actions.
Show more [+] Less [-]Protective effects of olive leaf extract against reproductive toxicity of the lead acetate in rats
2021
Ahmed, Harith Abdulrhman | Ali, Huda Abdullah | Mutar, Thulfiqar Fawwaz
Lead acetate (PbAc) is one of the toxic metals in the environment which causes many effects on different organs of the body. And due to the importance of the olive tree, with its healthy and protective elements against many diseases, the leaf extract of this tree was chosen in our study. Therefore, the aim of this study was to investigate the role of olive leaf (Olea europea L.) extract (OLE) against PbAc-induced sperm toxicity, sex hormone changes, oxidative stress, and histopathological changes in rats. Twenty male Wistar rats were divided into four groups (group 1, as control; group 2, OLE; group 3, PbAc; group 4, PbAc+OLE). In the PbAc group, the body weight, testis and epididymis weights, sexual hormones, sperm characteristics, GR, GPx, GST, GSH, SOD, and CAT were significantly decreased, and the sperm abnormality and TBARS level were significant increase when compared with control and OLE groups. Also, numerous damages to testicular tissue were observed in the PbAc group when compared to the control group, while the treatment with OLE in the fourth group led to improvement of sex hormones, semen characteristics, oxidative stress, and testicular tissue damage caused by PbAc. It can be concluded that OLE has a protective and ameliorative effects against PbAc-induced oxidative stress, apoptosis and alterations in testicular tissue, and sperm quality in rats.
Show more [+] Less [-]Bromelain and Olea europaea (L.) leaf extract mediated alleviation of benzo(a)pyrene induced lung cancer through Nrf2 and NFκB pathway
2021
Majumder, Debabrata | Debnath, Rahul | Nath, Priyatosh | Libin Kumar, K. V. | Debnath, Mousumi | Tribedi, Prosun | Maiti, Debasish
Lung cancer is the most aggressive as well as deadly form of cancer and most of the lung cancer cases are involved in direct smoking or passive smoking. Oxidative stress and pulmonary inflammation regulated by some transcription factors like Nrf2, NF-κB etc. play important roles in lung cancer. Various combinations of therapies are currently attributed to lung cancer treatment. A plethora of evidence supports that the consumption of plant-derived foods can prevent chronic diseases like cancer. Leaves of olive (Olea europaea L.) are rich in phenolic compounds which are having antioxidant and anti-inflammatory property. Also, bromelain from pineapple juice and from pineapple stem is a potent anti-inflammatory agent. We took a pragmatic approach to prevent carcinogenesis by supplementing the combination of these two extracts. In this study, we have tried to evaluate the amelioration of various hallmarks associated with benzo(a)pyrene-induced lung carcinogenesis upon the combinatorial treatment of ethanolic olive leaf extract (EOLE) and bromelain. We have studied the role of EOLE in amelioration of BaP-induced oxidative stress in the lung. As several reports of anticancer activity of bromelain are available, we have combined EOLE with bromelain to study their protective role against BaP-mediated lung damage. Changes in DNA integrity, LPO level in lung after EOLE-treated animal were examined. Then, we have evaluated the synergistic role of EOLE and bromelain. We have found that EOLE in combination with bromelain was able to increase the translocation of Nrf2 from cytoplasm to nucleus and decrease the translocation of NF-κB from cytoplasm to nucleus. Combination of treatment also reduced the expression of TNFα, IL-6, and some matrix metalloproteinases in lung tissue. Our findings suggest that EOLE and bromelain can synergistically reduce the BaP-induced lung carcinogenesis associated with inflammation and oxidative stress via regulating the expression of various inflammatory markers and also modulating the activity of pulmonary antioxidant armories.
Show more [+] Less [-]Synthesis and characterisation of stable and efficient nano zero valent iron
2018
Badmus, Kassim O. | Coetsee-Hugo, Elizabeth | Swart, Hendrik | Petrik, Leslie
Nano zero valent iron (nZVI) is an excellent adsorbent/reductant with wide applicability in remediation of persistent contaminants in soil, water and groundwater aquifers. There are concerns about its environmental fate, agglomeration, toxicity and stability in the air. Several modification methods have applied chistosan, green tea, carboxyl methyl cellulose and other coating substances to ensure production of nZVI with excellent air stability and effectiveness. The synthesis of a novel green nZVI (gNZVI) with Harpephyllum caffrum leaf extracts was successfully executed in the current study. Production of gNZVI involved the simultaneous addition of an optimum amount of the NaBH₄ and H. caffrum extract to FeCl₃ in an inert environment (Nitrogen). The solution was stirred for 30 min, washed with dilute ethanol (50%) and freeze dried. This procedure offered the best option for the synthesis of gNZVI in terms of nontoxic and inexpensive choice of stabiliser/reductant. Systematic characterisations using TGA, TEM, SEM, XRD, FT-IR and XPS confirmed the synthesis of crystalline, stable, reactive, well-dispersed and predominantly 50 nm diameter sized gNZVI compared to the conventionally synthesised nZVI which is 65 nm. The activity testing using Orange II sodium salt (OR2) confirmed the effectiveness of the synthesised gNZVI as an excellent Fenton catalyst with 65% degradation of 20 ppm OR2 dye in 1 h reaction time.
Show more [+] Less [-]Biofabrication of ecofriendly copper oxide nanoparticles using Ocimum americanum aqueous leaf extract: analysis of in vitro antibacterial, anticancer, and photocatalytic activities
2021
Manikandan, Dinesh Babu | Arumugam, Manikandan | Veeran, Srinivasan | Sridhar, Arun | Krishnasamy Sekar, Rajkumar | Perumalsamy, Balaji | Ramasamy, Thirumurugan
Nanotechnology tends to be a swiftly growing field of research that actively influences and inhibits the growth of bacteria/cancer. Noble metal nanoparticles (NPs) such as silver, copper, and gold have been used to damage bacterial and cancer growth over recent years; however, the toxicity of higher NPs concentrations remains a major issue. The copper oxide nanoparticles (CuONPs) were therefore fabricated using a simple green chemistry approach. Biofabricated CuONPs were characterized using UV-visible, FE-SEM with EDS, HR-TEM, FT-IR, XRD, Raman spectroscopy, and XPS analysis. Formations of CuONPs have been observed by UV-visible absorbance peak at 360.74 nm. The surface morphology of the CuONPs showed the spherical structure and size (~ 68 nm). The EDS spectrum of CuONPs has proved to be the key signals of copper (Cu) and oxygen (O) components. FT-IR analysis, to validate the important functional biomolecules (O–H, C=C, C–H, C–O) are responsible for reduction and stabilization of CuONPs. The monoclinic end-centered crystalline structures of CuONPs were confirmed with XRD planes. The electrochemical oxygen states of the CuONPs have been studied using spectroscopy of the Raman and X-ray photoelectron. After successful preparation, CuONPs examined their antibacterial, anticancer, and photocatalytic activities. Green-fabricated CuONPs were promising antibacterial candidate against human pathogenic gram-negative bacteria Escherichia coli, Vibrio cholerae, Salmonella typhimurium, Klebsiella pneumoniae, Aeromonas hydrophila, and Pseudomonas aeruginosa. CuONPs were demonstrated the excellent anticancer activity against A549 human lung adenocarcinoma cell line. Furthermore, CuONPs exhibited photocatalytic degradation of azo dyes such as eosin yellow (EY), rhodamine 123 (Rh 123), and methylene blue (MB). Biofabricated CuONPs may therefore be an important biomedical research for the aid of bacterial/cancer diseases and photocatalytic degradation of azo dyes.
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