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1.
Med Teach ; 46(3): 304-316, 2024 03.
Article in English | MEDLINE | ID: mdl-37677074

ABSTRACT

The World Health Organization (WHO) defines the Social Determinants of Health (SDOH) as the non-medical factors influencing health outcomes. SDOH is associated with conditions in which people are born, grow, work, and live. Medical schools and licensing bodies are increasingly recognizing the need for doctors and healthcare professionals to be aware of their patient's social context and how it impacts their states of health and disease. However, there is considerable variation in the approaches of different institutions and countries to incorporating SDOH into their curricula. In order to allow clinicians to adopt a holistic approach to patient health, equipping them with extensive knowledge of SDOH would give learners the confidence, skills, knowledge, and attitudes needed to effectively engage with patients and their families. This approach aids health professionals with knowledge of the influence of the social context and cultural factors that affect patients' behaviors in relation to health. Incorporating the SDOH in medical and health professional school curricula would contribute towards adequately preparing future healthcare practitioners to provide effective, comprehensive, and equitable care, especially to marginalized and underserved populations. The Guide will take an evidence-based approach grounded in the available contemporary literature and case studies. The focus will be on integrating SDOH into undergraduate and postgraduate medical curricula to promote an understanding of the social factors that influence patients' and communities' health. Ultimately, this guide seeks to contribute to the reduction of inequalities in health.


Subject(s)
Social Determinants of Health , Social Factors , Humans , Curriculum , Social Environment , Delivery of Health Care
2.
ACS Omega ; 8(39): 36553-36561, 2023 Oct 03.
Article in English | MEDLINE | ID: mdl-37810706

ABSTRACT

During the past decade, two-dimensional (2D) layered materials opened novel opportunities for the exploration of exciting new physics and devices owing to their physical and electronic properties. Among 2D materials, iron selenide has attracted much attention from several physicists as they provide a fruitful stage for developing new superconductors. Chemical doping offers a powerful approach to manipulate and optimize the electronic structure and physical properties of materials. Here, to reveal how doping affects the physical properties in FeSe, we report on complementary measurements of molybdenum- and sulfur-doped FeSe with theoretical calculations. Mo0.1Fe0.9Se0.9S0.1 was synthesized by a one-step solid-state reaction method. Crystal structure and morphology were studied using powder X-ray diffraction and scanning electron microscopy. Thermal stability and decomposition behavior in doped samples were studied by thermogravimetric analysis, and to understand the microscopic influence of doping, we performed Raman spectroscopy. First-principles calculations of the electronic structure illustrate distinct changes of electronic structures of the substituted FeSe systems, which can be responsible for their superconducting properties.

3.
Lett Appl Microbiol ; 76(7)2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37336598

ABSTRACT

Mimusops laurifolia is a native species restricted to the Red Sea mountains and Gulf of Aden. Its leaves contain saponins with wide range of biological activities. The presented research aimed to prepare saponins-rich extract from n-butanol fraction of M. laurifolia leaves and screen it for promising antimicrobial activities. Minimum inhibitory concentration (MIC) of the prepared saponins against Candida albicans, and their potential anti-pathogenic and antivirulence effects were determined. Different concentrations of the saponins-rich extract were investigated for their antimicrobial potential, particularly against C. albicans, using the agar well diffusion method. To assess the potential antivirulence and antipathogenic effects, we carried out molecular docking of the bioactive saponins against four key enzymes in C. albicans, which are involved in virulence and/or pathogenicity. Different concentrations of the investigated mixture showed notable antifungal activity against C. albicans with an MIC value of 6.4 µg ml-1. Docking analysis of the investigated saponins showed their affinity toward the docked enzymes, particularly saponin 1 with secreted aspartic proteinase 3 and saponin 6 with secreted aspartic proteinase 5. Thereafter, the stability of these two protein-ligand interactions was investigated using molecular dynamics (MD) simulation. The molecular interactions between saponins and the enzymes' active sites were analyzed and discussed.


Subject(s)
Anti-Infective Agents , Mimusops , Saponins , Saponins/pharmacology , Molecular Docking Simulation , Antifungal Agents/pharmacology , Anti-Infective Agents/pharmacology , Candida albicans , Plant Leaves/chemistry , Microbial Sensitivity Tests , Plant Extracts/pharmacology , Plant Extracts/chemistry
4.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 13.
Article in English | MEDLINE | ID: mdl-37259429

ABSTRACT

Rheumatoid arthritis (RA) is a long-term autoimmune disease. As nanotechnology has advanced, a growing number of nanodrugs have been used in the treatment of RA due to their unique physical and chemical properties. The purpose of this study was to assess the therapeutic potential of a novel zeolite/vitamin B12 nanocomposite (Nano ZT/Vit B12) formulation in complete Freund's adjuvant (CFA)-induced arthritis. The newly synthesized Nano ZT/Vit B12 was fully characterized using various techniques such as XRD, FT-IR, BET analysis, HERTEM, SEM, practical size, zeta potential, XRF, and EDX. The anti-arthritic, anti-inflammatory, and antioxidant activities as well as the immunomodulation effect of Nano ZT/Vit B12 on the CFA rat model of arthritis were examined. Histopathologic ankle joint injuries caused by CFA intrapedal injection included synovium hyperplasia, inflammatory cell infiltration, and extensive cartilage deterioration. The arthritic rats' Nano ZT/Vit B12 supplementation significantly improved these effects. Furthermore, in arthritic rats, Nano ZT/Vit B12 significantly reduced serum levels of RF and CRP, as well as the levels of IL-1ß, TNF-α, IL-17, and ADAMTS-5, while increasing IL-4 and TIMP-3 levels. Nano-ZT/Vit B12 significantly declined the LPO level and increased antioxidant activities, such as GSH content and GST activity, in the arthritic rats. In arthritic rats, Nano ZT/Vit B12 also reduced TGF-ß mRNA gene expression and MMP-13 protein levels. Collectively, Nano ZT/Vit B12 seems to have anti-arthritic, anti-inflammatory, and antioxidant properties, making it a promising option for RA in the future.

5.
Environ Sci Pollut Res Int ; 30(30): 74726-74741, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37249773

ABSTRACT

Waste (packaging plastic and industrial water) accumulation is one of the great global challenges over the world. Combining waste recycling science and water treatment knowledge are fascinating as applied sciences add value to the safe disposal of waste plastic packaging materials and wastewater. Active carbons (ACs) are prepared from polyethylene terephthalate (PET) at two pyrolysis temperatures (i.e. 450 and 500 °C) and compressed in well-defined designed molds to form cylinder shapes as applied in industry. Particle size (817 and 1074 nm), zeta potential (- 7.17 and - 25.6 mV), surface area (544 and 632 m2/g), and topography of prepared ACs were investigated and discussed. Zeta potential exhibited nice dispersion in accordance to charge value and surficial SEM images prove space hole filling with adsorbed materials after treatment. The prepared activated carbon sorbents have been applied for the removal of radioactive elements from wastewater. The displayed data declare that both sorbents have the same sorption performance, whereas the uranium sorption process using both sorbents is obeyed to pseudo-second-order kinetic model and Langmuir isotherm model. Nevertheless, it is worth noting that the prepared AC at a pyrolysis temperature of 500 °C exhibits higher sorption capacity (38.9 mg g-1) than that prepared at lower temperature, i.e., 450 °C (36.2 mg g-1) which indicates that the increase in pyrolysis temperature improves the sorption characteristics of the yield-activated carbon.


Subject(s)
Uranium , Water Pollutants, Chemical , Wastewater , Uranium/analysis , Charcoal , Adsorption , Kinetics , Plastics , Hydrogen-Ion Concentration , Water Pollutants, Chemical/analysis
6.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37111308

ABSTRACT

The usage of nanomaterials for rheumatoid arthritis (RA) treatment can improve bioavailability and enable selective targeting. The current study prepares and evaluates the in vivo biological effects of a novel hydroxyapatite/vitamin B12 nanoformula in Complete Freund's adjuvant-induced arthritis in rats. The synthesized nanoformula was characterized using XRD, FTIR, BET analysis, HERTEM, SEM, particle size, and zeta potential. We synthesized pure HAP NPs with 71.01% loading weight percentages of Vit B12 and 49 mg/g loading capacity. Loading of vitamin B12 on hydroxyapatite was modeled by Monte Carlo simulation. Anti-arthritic, anti-inflammatory, and antioxidant effects of the prepared nanoformula were assessed. Treated arthritic rats showed lower levels of RF and CRP, IL-1ß, TNF-α, IL-17, and ADAMTS-5, but higher IL-4 and TIMP-3 levels. In addition, the prepared nanoformula increased GSH content and GST antioxidant activity while decreasing LPO levels. Furthermore, it reduced the expression of TGF-ß mRNA. Histopathological examinations revealed an improvement in joint injuries through the reduction of inflammatory cell infiltration, cartilage deterioration, and bone damage caused by Complete Freund's adjuvant. These findings indicate that the anti-arthritic, antioxidant, and anti-inflammatory properties of the prepared nanoformula could be useful for the development of new anti-arthritic treatments.

7.
Mycoses ; 65(12): 1194-1201, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35943822

ABSTRACT

BACKGROUND: There has been an emergence of recalcitrant, recurrent, and difficult-to-treat tinea. Monotherapy with oral antifungals leads to partial clearance or high recurrence of lesions. Isotretinoin is a good adjuvant to systemic antifungals in chronic dermatophytosis. Voriconazole could be a future alternative due to its efficacy against dermatophytes and little resistance. OBJECTIVE: To evaluate the efficacy and safety of oral itraconazole, combined itraconazole/isotretinoin therapy, and voriconazole for recalcitrant tinea. PATIENTS AND METHODS: This study included 90 patients with chronic, recurrent and/or recalcitrant tinea. They were equally divided into three groups: itraconazole monotherapy, combined itraconazole/isotretinoin therapy, and voriconazole monotherapy. All patients received treatments for 6 weeks. The clinical response was classified as either a complete or incomplete clinical cure. Potassium hydroxide microscopy and culture were performed to identify mycological cure. Patients with complete cure were followed up for another 6 months to detect any recurrence. RESULTS: Complete clinical cure was observed in 53.3% of the itraconazole group, 70% of the itraconazole/isotretinoin group, and 83.3% of the voriconazole group. Mycological cure was detected in 56.7% of the itraconazole group, 83.3% of the itraconazole/isotretinoin group, and 86.7% of the voriconazole group. There was a statistically significant difference between the three groups in favour of voriconazole, then the combined group. No significant adverse effects were observed. The recurrence rate was significantly lower in the voriconazole group compared with the other two groups. CONCLUSIONS: Voriconazole could be a future alternative for the treatment of recalcitrant dermatophytosis.


Subject(s)
Itraconazole , Tinea , Humans , Itraconazole/adverse effects , Voriconazole/adverse effects , Antifungal Agents/adverse effects , Isotretinoin/adverse effects , Tinea/drug therapy , Tinea/diagnosis
8.
Sci Rep ; 11(1): 21141, 2021 10 27.
Article in English | MEDLINE | ID: mdl-34707203

ABSTRACT

Parkinson's disease (PD) is a progressive chronic neurodegenerative condition characterized by the loss of dopaminergic neurons within the substantia nigra. Current PD therapeutic strategies are mainly symptomatic and can lead to motor complications overtime. As a result, alternative medicine may provide an effective adjuvant treatment for PD as an addition to or as a replacement of the conventional therapies. The aim of this work was to evaluate the effects of Bee Venom (BV) and dopamine (DA)-loaded nanoparticles in a reserpine-induced animal model of PD. After inducing PD with reserpine injection, different groups of male rats were treated with L-Dopa, BV, DA-nanoparticles. Our findings showed that BV and DA-nanoparticles administration restored monoamines, balanced glutamate/GABA levels, halted DNA fragmentation, decreased pro-inflammatory mediators (IL-1ß and TNF-α), and elevated anti-inflammatory mediators (PON1) and neurotropic factor (BDNF) levels in comparison with conventional therapy of PD. Furthermore, in a reserpine-induced PD rat model, the ameliorative effects of BV were significantly superior to that of DA-nanoparticles. These findings imply that BV and DA-nanoparticles could be useful as adjuvant treatments for PD.


Subject(s)
Antiparkinson Agents/therapeutic use , Bee Venoms/therapeutic use , Dopamine/therapeutic use , Nanoparticles , Parkinson Disease/drug therapy , Animals , Antiparkinson Agents/administration & dosage , Antiparkinson Agents/pharmacology , Bee Venoms/administration & dosage , Bee Venoms/pharmacology , Brain-Derived Neurotrophic Factor/metabolism , DNA Fragmentation , Dopamine/administration & dosage , Dopamine/pharmacology , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/metabolism , Interleukin-1beta/metabolism , Male , Parkinson Disease/etiology , Rats , Reserpine/toxicity , Tumor Necrosis Factor-alpha/metabolism , gamma-Aminobutyric Acid/metabolism
9.
Physiol Mol Biol Plants ; 26(6): 1155-1171, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32549680

ABSTRACT

Algal supplements can improve crop productivity and afford protection against abiotic stress by virtue of their rich content of plant nutrients and bioactive compounds. The present work investigates the relative efficiency of the biomass and extract of the brown alga Dictyota dichotoma in protection of rice against salinity and water stress. Rice (Oryza sativa L.) cv. Sakha 101 was grown on a silty clay soil amended with the aqueous extract and powder of D. dichotoma under NaCl and PEG 6000 stress at water potential of - 0.492 MPa. Abiotic stress, particularly water stress, reduced rice growth and concentrations of K+ and protein but increased soluble sugars, starch, proline and Na+ concentrations of plant tissues, with counterbalancing effect of algal amendment. The benefit of algal amendment was greater for algal extract than algal powder and under water stress than salt stress. Algal amendment and abiotic stress promoted catalase and peroxidase activities in rice leaves with variable effect on polyphenol oxidase. The benefit of D. dichotoma to rice can be related to macro- and micro-nutrients, growth hormones, phenolics, flavonoids, sterols, vitamins and fucoidan. The production of toxic intermediates as a result of fermentation of the algal biomass in the paddy soil might reduce the benefit of algal amendment. Although rice is salt-sensitive, it is more resistant to salt stress than to drought stress. The ability of rice to retain Na+ in the root is pivotal for stress resistance, but the role of K+ partitioning is less evident.

10.
Am J Cardiol ; 125(2): 198-204, 2020 01 15.
Article in English | MEDLINE | ID: mdl-31740020

ABSTRACT

Role of omega-3-Fatty acids, especially eicosapentaenoic acid (EPA), in reducing cardiovascular events is not clear. We conducted a meta-analysis including trial sequential analysis (TSA) of all available randomized controlled trials (RCTs) assessing the impact of EPA + statin on cardiovascular risk reduction. The aim is to appraise cardiovascular risk reduction with EPA and statin taken together. A comprehensive search of PubMed and EMBASE databases was conducted for all RCTs that compared EPA + Statin versus statin alone and included outcomes related to cardiovascular health. We calculated a comprehensive odds ratio (ORs) and 95% confidence intervals (CIs) using a random-effects model. We included 5 RCTs totaling 27,415 patients. Our results demonstrated that EPA + statin resulted in 18% reduction in the incidence of MACE (OR = 0.78; 95% CI: 0.65 to 0.93, I2 = 54%, p value <0.01) and 30% reduction in myocardial infarction (MI) (OR = 0.71; 95% CI: 0.61 to 0.82, I2 = 0% p value <0.01) as compared with statin alone. With respect to MACE, the number needed to treat was 49. The statistical significance for reduction in the incidence of MACE with EPA+ statin was further augmented with trial sequential analysis. However, combined therapy of EPA + statin demonstrated no significant association on incidence of stroke when compared with statin alone or all-cause mortality. In conclusion, this meta-analysis demonstrated that EPA significantly reduced the incidence of MACE when combined with statin therapy, which is mainly driven by a significant reduction in myocardial infarction.


Subject(s)
Cardiovascular Diseases/prevention & control , Eicosapentaenoic Acid/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Cardiovascular Diseases/epidemiology , Cause of Death/trends , Global Health , Humans , Incidence , Survival Rate/trends
11.
J Colloid Interface Sci ; 560: 825-837, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31711669

ABSTRACT

The capacity of an adsorbent to bind and remove dye from solution greatly depends on the type of functionalization present on the nanoparticles surface, and its interaction with the dye molecules. Within this study, nitrogenous silane nanoparticles were hydrothermally synthesized resulting in the formation of rapid and highly efficient adsorbents for concentrated mixed dyes. The amorphous silane nanoparticles exhibited a monolayer based mechanism of mixed dye adsorption with removal capacities between 416.67 and 714.29 mg/g of adsorbent. Dye removal was predominantly due to the electrostatic attraction between the positively charged silane nanoparticles (13.22-8.20 mV) and the negatively charged dye molecules (-54.23 mV). Addition of H. annuus extract during synthesis resulted in three times the surface area and 10 times increased pore volume compared to the positive control. XPS analysis showed that silane treatments had various nitrogen containing functionalities at their surface responsible for binding dye. The weak colloidal stability of silane particles (13.22-8.20 mV) was disrupted following dye binding, resulting in their rapid coagulation and flocculation which facilitated the separation of bound dye molecules from solution. The suitability for environmental applications using these treatments was supported by a bacterial viability assay showing >90% cell viability in treated dye supernatants.


Subject(s)
Coloring Agents/isolation & purification , Helianthus/chemistry , Nanoparticles/chemistry , Nitrogen/chemistry , Plant Extracts/chemistry , Silanes/chemistry , Water Pollutants, Chemical/isolation & purification , Adsorption , Bacteria/drug effects , Bacteria/growth & development , Coloring Agents/chemistry , Environment , Nanoparticles/administration & dosage , Water Pollutants, Chemical/chemistry
12.
Molecules ; 24(18)2019 Sep 19.
Article in English | MEDLINE | ID: mdl-31546774

ABSTRACT

Petroleum hydrocarbons represent the most frequent environmental contaminant. The introduction of petroleum hydrocarbons into a pristine environment immediately changes the nature of that environment, resulting in reduced ecosystem functionality. Natural attenuation represents the single, most important biological process which removes petroleum hydrocarbons from the environment. It is a process where microorganisms present at the site degrade the organic contaminants without the input of external bioremediation enhancers (i.e., electron donors, electron acceptors, other microorganisms or nutrients). So successful is this natural attenuation process that in environmental biotechnology, bioremediation has developed steadily over the past 50 years based on this natural biodegradation process. Bioremediation is recognized as the most environmentally friendly remediation approach for the removal of petroleum hydrocarbons from an environment as it does not require intensive chemical, mechanical, and costly interventions. However, it is under-utilized as a commercial remediation strategy due to incomplete hydrocarbon catabolism and lengthy remediation times when compared with rival technologies. This review aims to describe the fate of petroleum hydrocarbons in the environment and discuss their interactions with abiotic and biotic components of the environment under both aerobic and anaerobic conditions. Furthermore, the mechanisms for dealing with petroleum hydrocarbon contamination in the environment will be examined. When petroleum hydrocarbons contaminate land, they start to interact with its surrounding, including physical (dispersion), physiochemical (evaporation, dissolution, sorption), chemical (photo-oxidation, auto-oxidation), and biological (plant and microbial catabolism of hydrocarbons) interactions. As microorganism (including bacteria and fungi) play an important role in the degradation of petroleum hydrocarbons, investigations into the microbial communities within contaminated soils is essential for any bioremediation project. This review highlights the fate of petroleum hydrocarbons in tertial environments, as well as the contributions of different microbial consortia for optimum petroleum hydrocarbon bioremediation potential. The impact of high-throughput metagenomic sequencing in determining the underlying degradation mechanisms is also discussed. This knowledge will aid the development of more efficient, cost-effective commercial bioremediation technologies.


Subject(s)
Ecosystem , Hydrocarbons/analysis , Microbiota , Petroleum Pollution/analysis , Petroleum/analysis , Biodegradation, Environmental , Hydrocarbons/toxicity , Microbiota/drug effects
13.
Int J Neurosci ; 128(10): 946-951, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29493311

ABSTRACT

BACKGROUND: It has been suggested that vitamin D influences the immunoregulation and subsequently affects the risk for conversion of clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (MS). There is little information regarding the relationship between levels of vitamin D and CIS conversion to MS in Egyptian patients. OBJECTIVE: It is to study contribution of vitamin D deficiency to conversion of CIS to clinically definite multiple sclerosis (CDMS) and correlation of vitamin D level to cognitive and magnetic resonance imaging (MRI) results. PATIENTS AND METHODS: A longitudinal prospective case control study was conducted on 43 Egyptian patients diagnosed as CIS according to McDonald criteria (2010). Clinical presentation, brain MRI and 25-hydroxyvitamin D levels were evaluated at baseline and after one-year follow-up. RESULTS: The CIS patients that converted to MS showed significant lower vitamin D level (p < 0.001) than the non-convertors. Multivariate logistic regression analysis revealed that the CIS patients with lower 25-hydroxyvitamin D level (p < 0.001) are at higher risk for early conversion to MS. There was a significant positive correlation between the vitamin D level and PASAT (r = 0.36, p = 0.02). It was found that there was a significant negative correlation between vitamin D level and MRI T2 load (r = -0.38, p = 0.01). CONCLUSION: The low level of 25-hydroxyvitamin D may predict early conversion to clinically definite MS. Early vitamin D supplementation is recommended in patients with CIS.


Subject(s)
Brain/diagnostic imaging , Cognitive Dysfunction/physiopathology , Demyelinating Diseases , Disease Progression , Vitamin D Deficiency/blood , Vitamin D/analogs & derivatives , Adolescent , Adult , Case-Control Studies , Cognitive Dysfunction/etiology , Demyelinating Diseases/blood , Demyelinating Diseases/complications , Demyelinating Diseases/diagnostic imaging , Demyelinating Diseases/physiopathology , Egypt , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Multiple Sclerosis/blood , Multiple Sclerosis/complications , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/physiopathology , Vitamin D/blood , Young Adult
14.
J Pharm Biomed Anal ; 146: 126-134, 2017 Nov 30.
Article in English | MEDLINE | ID: mdl-28869815

ABSTRACT

Isolation of bioactive compounds from extracts of pharmaceutical plant is very important. In this work, copper benzene-1,3,5-tricarboxylate metal organic framework (Cu-BTC MOF) has been synthesized. It is used in separating of chamazulene from chamomile extract. The Cu-BTC MOF not only shows good chamazulene adsorption but also maintains good desorption properties. However, the research on this field is still new and the maturation of novel MOFs or the enhancements of known ones are required.The chamomile extract obtained after each stage of the treatments was carefully characterized by thin-layer chromatography (TLC), Fourier-transform infrared spectroscopy (FTIR), UV-vis spectrometry and gas chromatography-mass spectrometry (GC-MS). The morphology and the crystallinity of Cu-BTC MOF were investigated using scanning electron microscopy (SEM) and powder X-ray diffraction (PXRD), respectively. Breakthrough experiments in a column was investigated and the data was fitted with Bohart-Adams model. Monte Carlo simulation was conducted to investigate the preferential adsorption sites of Cu-BTC for chamazulene molecules.


Subject(s)
Azulenes/chemistry , Chamomile/chemistry , Metal-Organic Frameworks/chemistry , Adsorption , Chromatography, Thin Layer/methods , Copper/chemistry , Gas Chromatography-Mass Spectrometry/methods , Organometallic Compounds/chemistry , Plant Extracts/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Tricarboxylic Acids/chemistry , X-Ray Diffraction/methods
15.
J Phys Chem B ; 121(27): 6456-6470, 2017 07 13.
Article in English | MEDLINE | ID: mdl-28616992

ABSTRACT

Characterization of a protein in the context of its environment is of crucial importance for a complete understanding of its function. Although biophysical techniques provide powerful tools for studying the stability and activity of the enzyme in the presence of various cosolvents, an approach of combining both experimental techniques and molecular dynamic (MD) simulations may lead to the mechanistic insight into the interactions governing the stability of an enzyme. The knowledge of these interactions can be further utilized for range of modifications in the wild form of an enzyme for various pharmaceutical applications. Herein, we employed florescence, UV-visible, circular dichroism (CD), dynamic light scattering (DLS) study, and MD simulations for comprehensive understanding of stem bromelain (BM) in the presence of betaine, sarcosine, arginine, and proline. The thermal stability of BM in the presence of 1 M of osmolytes is found to be in order: proline > betaine > buffer > arginine > sarcosine. BM gets more preferentially hydrated in the presence of betaine and proline than in sarcosine and arginine. Nonetheless, MD simulations suggest that betaine, sarcosine, and arginine at 1 M interact with the active site of BM through H-bonding except proline which are responsible for more disruption of active site. The distances between the catalytic site residues are 1.6, 1.9, 4.3, 5.0, and 6.2 Å for BM in proline, buffer, betaine, arginine, and sarcosine at 1 M, respectively. To the best of our knowledge, this is the first report on detailed unequivocal evidence of denaturation and deactivation of BM in the presence of methylamines and amino acids.


Subject(s)
Bromelains/chemistry , Molecular Dynamics Simulation , Osmometry , Bromelains/metabolism , Circular Dichroism , Dynamic Light Scattering , Protein Denaturation , Temperature
16.
Ecotoxicol Environ Saf ; 133: 297-305, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27479774

ABSTRACT

Bioremediation is a broadly applied environmentally friendly and economical treatment for the clean-up of sites contaminated by petroleum hydrocarbons. However, the application of this technology to contaminated soil in Libya has not been fully exploited. In this study, the efficacy of different bioremediation processes (necrophytoremediation using pea straw, bioaugmentation and a combination of both treatments) together with natural attenuation were assessed in diesel contaminated Libyan soils. The addition of pea straw was found to be the best bioremediation treatment for cleaning up diesel contaminated Libyan soil after 12 weeks. The greatest TPH degradation, 96.1% (18,239.6mgkg(-1)) and 95% (17,991.14mgkg(-1)) were obtained when the soil was amended with pea straw alone and in combination with a hydrocarbonoclastic consortium respectively. In contrast, natural attenuation resulted in a significantly lower TPH reduction of 76% (14,444.5mgkg(-1)). The presence of pea straw also led to a significant increased recovery of hydrocarbon degraders; 5.7log CFU g(-1) dry soil, compared to 4.4log CFUg(-1) dry soil for the untreated (natural attenuation) soil. DGGE and Illumina 16S metagenomic analyses confirm shifts in bacterial communities compared with original soil after 12 weeks incubation. In addition, metagenomic analysis showed that original soil contained hydrocarbon degraders (e.g. Pseudoxanthomonas spp. and Alcanivorax spp.). However, they require a biostimulant (in this case pea straw) to become active. This study is the first to report successful oil bioremediation with pea straw in Libya. It demonstrates the effectiveness of pea straw in enhancing bioremediation of the diesel-contaminated Libyan soil.


Subject(s)
Biodegradation, Environmental , Petroleum/metabolism , Soil Pollutants/metabolism , Soil/chemistry , Libya , Petroleum/analysis , Soil Microbiology , Soil Pollutants/chemistry
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