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1.
Ann Hematol ; 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37414960

RESUMEN

Waldenström macroglobulinemia (WM) is a chronic B-cell lymphoproliferative disorder characterized by lymphoplasmacytic cell overgrowth in the bone marrow and increased secretion of IgM immunoglobulins into the serum. Patients with WM have a variety of clinical outcomes, including long-term survival but inevitable recurrence. Recent advances in disease knowledge, including molecular and genetic principles with the discovery of MYD88 and CXCR4 mutations, have rapidly increased patient-tolerable treatment options. WM patients may benefit from chemotherapy regimens that include rituximab-based regimens, alkylating drugs, proteasome inhibitors, monoclonal antibodies, and drugs targeting Bruton tyrosine kinase inhibitors. In light of these advancements, patients can now receive treatment customized to their specific clinical characteristics, focusing on enhancing the depth and durability of their response while limiting the adverse effects. Despite the rapidly developing therapeutic armament against WM, a lack of high-quality evidence from extensive phase 3 trials remains a significant challenge in the research. We believe clinical outcomes will keep improving when new medicines are introduced while preserving efficacy and minimizing toxicity.

2.
Int J Mol Sci ; 24(1)2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36614205

RESUMEN

Landfill leachate (LFL) treatment is a severe challenge due to its highly viscous nature and various complex pollutants. Leachate comprises various toxic pollutants, including inorganic macro/nano components, xenobiotics, dissolved organic matter, heavy metals, and microorganisms responsible for severe environmental pollution. Various treatment procedures are available to achieve better effluent quality levels; however, most of these treatments are nondestructive, so pollutants are merely transported from one phase to another, resulting in secondary contamination. Anaerobic digestion is a promising bioconversion technology for treating leachate while producing renewable, cleaner energy. Because of its high toxicity and low biodegradability, biological approaches necessitate employing other techniques to complement and support the primary process. In this regard, pretreatment technologies have recently attracted researchers' interest in addressing leachate treatment concerns through anaerobic digestion. This review summarizes various LFL pretreatment methods, such as electrochemical, ultrasonic, alkaline, coagulation, nanofiltration, air stripping, adsorption, and photocatalysis, before the anaerobic digestion of leachate. The pretreatment could assist in converting biogas (carbon dioxide to methane) and residual volatile fatty acids to valuable chemicals and fuels and even straight to power generation. However, the selection of pretreatment is a vital step. The techno-economic analysis also suggested the high economic feasibility of integrated-anaerobic digestion. Therefore, with the incorporation of pretreatment and anaerobic digestion, the process could have high economic viability attributed to bioenergy production and cost savings through sustainable leachate management options.


Asunto(s)
Reactores Biológicos , Contaminantes Ambientales , Anaerobiosis , Biocombustibles/análisis , Estudios de Factibilidad , Contaminantes Ambientales/análisis , Metano/análisis
3.
Environ Monit Assess ; 195(9): 1100, 2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37632590

RESUMEN

Pakistan is the fourth largest yarn producer in the world heavily that relies on cotton crop which receives a substantial 62% of all pesticide applications. The present study was conducted to quantify the levels of pesticides such as bifenthrin, spirotetramat, pyriproxyfen, imidacloprid, and diafenthiuron in soil and plants residue at selected cotton fields of Multan District, Pakistan. In addition to pesticides, the assessment of heavy metal concentration was also conducted in order to determine the overall risks that these compounds to both plants and human population. For this analysis, 20 soil samples and 10 plant samples were collected from 10 selected cotton fields. Pesticides and heavy metals in soil and plant samples were analyzed using high-performance liquid chromatography (HPLC) and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), respectively. It was observed that all samples collected from selected fields contained pesticide residue in top soil (0-15 cm). However, no pesticides were detected in the lower soil layer (16-30 cm). In case of heavy metals, the highest concentration of Fe, Pb, and Mn was observed in both soil and plant residue samples. The heavy metals were found in the order of Fe > Mn > Pb > Zn > Cu > Cd in the soil. The total carcinogenic risk values for a few pesticides were found to range from 10-6 to 10-2, indicating that residents of the study area have low to higher chances of developing cancer. A positive correlation was observed among the pesticides (r = 0.18-0.95) as well as in metals related parameters (r = 0.49-0.96), where a weak negative correlation was found among metal to pesticide parameters except Pd where the maximum r value was 0.62. In general, the finding of this study encourages the development and adoption of sustainable agricultural practices that lower the dependence on toxic pesticides and endorse environmentally friendly alternatives.


Asunto(s)
Contaminantes Ambientales , Neoplasias , Plaguicidas , Humanos , Pakistán/epidemiología , Plomo , Monitoreo del Ambiente , Celulosa , Medición de Riesgo
4.
Environ Monit Assess ; 195(7): 901, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37380756

RESUMEN

Heavy metal contamination in surface water is widespread throughout the world as a result of numerous anthropogenic activities and geo-genic mechanisms. This contamination is also affecting aquatic life, as fish have the potential to acquire heavy metals in their tissues making them vulnerable. Worldwide lakes are an important source of water for the inhabitants of the area. So, in the present study, we have focused on the Satpara Lake to check the extent of heavy metal pollution and their accumulation in fish to provide baseline data for metal pollution management. Samples were collected from three locations (inflow, center, and outflow sites) during two seasons (summer and winter). Inductively coupled plasma optical emission spectrometry (ICP-OES) was applied to analyze heavy metals concentration. Among the metals, Cd, Pb, As, and Fe revealed relatively higher concentrations. The highest concentration of heavy metal found in water and fish was of Cd, i.e., 8.87 mg L-1 and 18.19 mg L-1 in summer season, respectively. Arsenic concentration was also higher than the permissible limits in both water (0.76) and fish (1.17 mg L-1). The water quality assessment showed that in the summer season, the HPI (heavy metal pollution index) value 253.01 was more than 100, indicating the bad quality of water for drinking purposes. However, the HPI value 35.72 was less than 100 in winter. Toxicity hazard calculation of fish in summer seasons gives Hi values greater than 10.0, indicating the acute effect on human health as compared to winter.


Asunto(s)
Lagos , Metales Pesados , Animales , Humanos , Estaciones del Año , Trucha , Cadmio , Monitoreo del Ambiente , Calidad del Agua
5.
Waste Manag Res ; 40(12): 1708-1729, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35719093

RESUMEN

With the huge generation of municipal solid waste (MSW), proper management and disposal of MSW is a worldwide challenge for sustainable development of cities and high quality of citizens life. Although different disposal ways are available, incineration is a leading harmless approach to effectively recover energy among the applied technologies. The purpose of the present review paper is to detail the discussion of evolution of waste to energy incineration and specifically to highlight the currently used and advanced incineration technologies, including combined incineration with other energy, for instance, hydrogen production, coal and solar energy. In addition, the environmental performance is discussed, including the zero waste emission, leachate and fly ash treatment, climate change contribution and public behaviour. Finally, challenges, opportunities and business model are addressed. Trends and perspectives on policies and techno-economic aspects are also discussed in this review. Different simulation tools, which can be used for the thermodynamic assessment of incineration plants, are debated; life-cycle inventory emissions and most critical environmental impacts of such plants are evaluated by life-cycle analysis. This review shows that waste incineration with energy yield is advantageous to handle waste problems and it affects climate change positively.


Asunto(s)
Incineración , Eliminación de Residuos , Residuos Sólidos/análisis , Ceniza del Carbón/análisis , Cambio Climático , Carbón Mineral , Hidrógeno
6.
J Sci Food Agric ; 100(6): 2688-2704, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32002999

RESUMEN

BACKGROUND: Kinnow orchards were selected in different ecological zones in districts Sargodha, Toba Tek Singh (TTS) and Vehari of the Punjab province, Pakistan. Three biological replicates in block form were applied by using analysis of variance techniques to assess varying agrometeorological indices impact on fruit color-development and peel composition. RESULTS: Fruit samples were randomly collected on each month's end starting from August up to February. Chromameter was used for measuring coloring parameters and its values a*, b*, C* and L* were increased from August till February with a rapid elevation started at color-break stage, while hue angle (h*) rotated from 120° to 60° of portraying green to yellow shade. An increasing level of chlorophyll contents were noted in August till color-break at the end of October and then diminished afterwards. Whereas, carotenoids increased rapidly upon yellow tinting peel of Kinnow fruits till fully attained deep orange color at the end of February. Ascorbic acid content and total phenolic content (TPC) showed a decreasing trend whereas anthocyanins and antioxidant activity were increased from August to February, with unchanged flavonoids and flavonols level. Fruit firmness was gradually reduced till color-break with rapid reduction noted subsequently. Maturity index represented internal ripening directly increased with color-development. CONCLUSION: Color development has directly influenced on maturity index and both were increased rapidly after color-break to afterwards. More color development with rapid reduction in chlorophyll, ascorbic acid and TPC level were seen in warm districts namely TTS and Vehari after color-break stage due to accumulating more agrometeorological indices. © 2020 Society of Chemical Industry.


Asunto(s)
Citrus/química , Color , Frutas/química , Ácido Ascórbico/análisis , Clorofila/análisis , Clima , Pakistán , Fenoles/análisis , Estaciones del Año
7.
Toxicol Ind Health ; 35(2): 145-158, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30654724

RESUMEN

The populations of wild animals are declining in many parts of the world in response to man-made alterations in the environment. Environmental contamination due to heavy metals discharge from industry may contribute to the decline of wild animal populations by impacting their reproduction, growth, and development. In the leather tanning industry, chromium (Cr) is used as a basic component, but it is a potent toxicant that can affect many of the physiological functions of animals. In the current study, we investigated the reproductive toxicity of industrial Cr in female small Indian mongooses inhabiting a tannery area. Adult female specimens were live trapped from February 2015 to January 2016. Blood and other body tissues (ovaries, kidneys and liver) of the captured specimens were collected along with soil and water samples from the environment for analysis. The Cr concentrations were found significantly ( p < 0.0001) increased compared to control in the environment, blood, and all body tissues of the animals. Estradiol and progesterone levels were found to be significantly decreased in comparison with control ( p < 0.0001), along with reduced ovarian weights, while follicle stimulating hormone (FSH) and luteinizing hormone levels were found significantly ( p < 0.0001) elevated. Light microscopy revealed significantly decreased in comparison with control ovarian follicle numbers ( p < 0.0001) and diameters, vacuolization of the oocytes, and a significantly higher percentage of atretic follicles inside the ovary. We conclude that Cr discharged from the tanneries is absorbed by the exposed female small Indian mongoose, leading to ovarian dysfunction with potential impairment of reproductive function.


Asunto(s)
Cromo/toxicidad , Contaminación Ambiental/efectos adversos , Herpestidae/fisiología , Folículo Ovárico , Curtiembre , Animales , Peso Corporal/efectos de los fármacos , Cromo/análisis , Cromo/farmacocinética , Femenino , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/patología , Pakistán , Progesterona/sangre , Distribución Tisular
8.
Waste Manag Res ; 35(9): 967-977, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28735564

RESUMEN

Catering waste and orange peel were co-digested using an anaerobic digestion process. Orange peel is difficult to degrade anaerobically due to the presence of antimicrobial agents such as limonene. The present study aimed to examine the feasibility of anaerobic co-digestion of catering waste with orange peel to provide the optimum nutrient balance with reduced inhibitory effects of orange peel. Batch experiments were conducted using catering waste as a potential substrate mixed in varying ratios (20-50%) with orange peel. Similar ratios were followed using green vegetable waste as co-substrate. The results showed that the highest organic matter degradation (49%) was achieved with co-digestion of catering waste and orange peel at a 50% mixing ratio (CF4). Similarly, the soluble chemical oxygen demand (sCOD) was increased by 51% and reached its maximum value (9040 mg l-1) due to conversion of organic matter from insoluble to soluble form. Biogas production was increased by 1.5 times in CF4 where accumulative biogas was 89.61 m3 t-1substrate compared with 57.35 m3 t-1substrate in the control after 80 days. The main reason behind the improved biogas production and degradation is the dilution of inhibitory factors (limonene), with subsequent provision of balanced nutrients in the co-digestion system. The tCOD of the final digestate was decreased by 79.9% in CF4, which was quite high as compared with 68.3% for the control. Overall, this study revealed that orange peel waste is a highly feasible co-substrate for anaerobic digestion with catering waste for enhanced biogas production.


Asunto(s)
Biocombustibles , Reactores Biológicos , Anaerobiosis , Análisis de la Demanda Biológica de Oxígeno , Metano
9.
Crit Rev Biotechnol ; 36(4): 639-51, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25665634

RESUMEN

Azo dyes and their intermediate degradation products are common contaminants of soil and groundwater in developing countries where textile and leather dye products are produced. The toxicity of azo dyes is primarily associated with their molecular structure, substitution groups and reactivity. To avoid contamination of natural resources and to minimize risk to human health, this wastewater requires treatment in an environmentally safe manner. This manuscript critically reviews biological treatment systems and the role of bacterial reductive and oxidative enzymes/processes in the bioremediation of dye-polluted wastewaters. Many studies have shown that a variety of culturable bacteria have efficient enzymatic systems that can carry out complete mineralization of dye chemicals and their metabolites (aromatic compounds) over a wide range of environmental conditions. Complete mineralization of azo dyes generally involves a two-step process requiring initial anaerobic treatment for decolorization, followed by an oxidative process that results in degradation of the toxic intermediates that are formed during the first step. Molecular studies have revealed that the first reductive process can be carried out by two classes of enzymes involving flavin-dependent and flavin-free azoreductases under anaerobic or low oxygen conditions. The second step that is carried out by oxidative enzymes that primarily involves broad specificity peroxidases, laccases and tyrosinases. This review focuses, in particular, on the characterization of these enzymes with respect to their enzyme kinetics and the environmental conditions that are necessary for bioreactor systems to treat azo dyes contained in wastewater.


Asunto(s)
Compuestos Azo/metabolismo , Proteínas Bacterianas/metabolismo , Colorantes/metabolismo , Oxidorreductasas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Compuestos Azo/toxicidad , Bacterias/metabolismo , Biodegradación Ambiental , Colorantes/toxicidad , Humanos , Contaminantes Químicos del Agua/toxicidad
10.
Ecotoxicol Environ Saf ; 124: 42-49, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26454074

RESUMEN

Biological treatment of azo dyes commonly requires a combined anaerobic-aerobic process in which initial decolorization is achieved by reductive cleavage of azo bonds on the parent molecule. The present study was conducted to examine the relative importance of co-substrates for driving reductive decolorization of azo dyes by Shewanella sp. strain IFN4 using whole cells and enzyme assays. Results showed that the dye decolorization by strain IFN4 was faster in medium containing 1gL(-1) yeast extract (YE) as compared to nine other co-substrates. Moreover, only YE stimulated azoreductase activity (increased from 1.32 to 4.19U/mg protein). Increasing the level of YE up to 8gL(-)(1) resulted into 81% decolorization of the dye in 1h along with an increase in azoreductase activity up to 6.16U/mg protein. Among the components of YE, only riboflavin stimulated the decolorization process as well as enzyme activity. Moreover, strain IFN4 demonstrated flavin reductase activity, and a significant correlation (r(2)=0.98) between flavin reduction and dye reduction by this strain emphasized the involvement of flavin compounds in the decolorization process. The results of this study show that YE serves both as a source of reducing equivalents and an electron shuttle for catalyzing dye reduction.


Asunto(s)
Compuestos Azo/metabolismo , Colorantes/metabolismo , Mezclas Complejas/metabolismo , Shewanella/metabolismo , Levaduras/química , NADH NADPH Oxidorreductasas/metabolismo , Nitrorreductasas , Oxidación-Reducción
11.
Ecotoxicol Environ Saf ; 120: 163-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26074308

RESUMEN

The aim of this study was to examine the stability of structurally different azo dyes in soil and their impact on the microbial community composition by analyzing phospholipid fatty acid (PLFA) profiles. Sterile and non-sterile soils were amended with three azo dyes, including: Direct Red 81, Reactive Black 5 and Acid Yellow 19 at 160mgkg(-1) soil. The results showed that the azo dyes were quite stable and that large amounts of these dyes ranging from 17.3% to 87.5% were recoverable from the sterile and non-sterile soils after 14 days. The maximum amount of dye was recovered in the case of Direct Red 81. PLFA analysis showed that the azo dyes had a significant effect on microbial community structure. PLFA concentrations representing Gram-negative bacteria in dye-amended soil were substantially less as compared to the PLFA concentration of Gram-positive bacteria. Acid Yellow 19 dye had almost similar effects on the PLFA concentrations representing bacteria and fungi. In contrast, Reactive Black 5 had a greater negative effect on fungal PLFA than that on bacterial PLFA, while the opposite was observed in the case of Direct Red 81. To our knowledge, this is the first study reporting the stability of textile azo dyes in soil and their effects on soil microbial community composition.


Asunto(s)
Compuestos Azo/química , Ácidos Grasos/química , Fosfolípidos/química , Microbiología del Suelo , Contaminantes del Suelo/química , Textiles , Bacterias/química , Bacterias/efectos de los fármacos , Hongos/química , Hongos/efectos de los fármacos , Suelo/química
12.
Int J Phytoremediation ; 17(11): 1060-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25849115

RESUMEN

Azo dyes are commonly generated as effluent pollutants by dye using industries, causing contamination of surface and ground water. Various strategies are employed to treat such wastewater; however, a multi-faceted treatment strategy could be more effective for complete removal of azo dyes from industrial effluent than any single treatment. In the present study, rice husk material was used as a substratum in two constructed wetlands (CWs) and augmented with microorganisms in the presence of wetland plants to effectively treat dye-polluted water. To evaluate the efficiency of each process the study was divided into three levels, i.e., adsorption of dye onto the substratum, phytoremediation within the CW and then bioremediation along with the previous two processes in the augmented CW. The adsorption process was helpful in removing 50% dye in presence of rice husk while 80% in presence of rice husk biocahr. Augmentation of microorganisms in CW systems has improved dye removal efficiency to 90%. Similarly presence of microorganisms enhanced removal of total nitrogen (68% 0 and Total phosphorus (75%). A significant improvement in plant growth was also observed by measuring plant height, number of leaves and leave area. These findings suggest the use of agricultural waste as part of a CW substratum can provide enhanced removal of textile dyes.


Asunto(s)
Bacterias/metabolismo , Colorantes/metabolismo , Naftalenosulfonatos/metabolismo , Oryza/química , Polygonaceae/metabolismo , Contaminantes Químicos del Agua/metabolismo , Humedales , Adsorción , Agricultura , Biodegradación Ambiental , Grano Comestible/química , Manipulación de Alimentos , Residuos Industriales/análisis , Pakistán , Industria Textil , Aguas Residuales/análisis
13.
Water Environ Res ; 87(7): 579-86, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26163493

RESUMEN

In this study, effect of various metal ions and salts on biodecolorization of Reactive black-5, azoreductase activity, and growth of Shewanella sp. strain IFN4 was evaluated. Among the tested metals, Cr²âº, Pb(²âº, Ni²âº, Fe²âº, and Mn²âº did not inhibit the biodecolorization of reactive black-5, azoreductase activity and bacterial growth. Three metals (Cu²âº, Zn²âº, and Co²âº) delayed the decolorization process without completely inhibiting the reaction and also suppressed the bacterial growth. However, no dye decolorization was observed in the presence of Cd²âº (10 mg L⁻¹). Furthermore, bacterium decolorized the dye at high concentration (15 mg L⁻¹) of mixed metal ions. Strain IFN4 was also able to decolorize the dye at 50 g NaCl L⁻¹ and 60 g Na2SO4 L⁻¹. NaCl was found to be more inhibitory to bacterial growth than Na2SO4and the reverse was observed for azoreductase activity. These findings suggest that strain IFN4 could be used in designing a bioreactor for the treatment of textile effluent.


Asunto(s)
Metales/farmacología , Naftalenosulfonatos/química , Shewanella/metabolismo , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Relación Dosis-Respuesta a Droga , Metales/administración & dosificación , NADH NADPH Oxidorreductasas/metabolismo , Nitrorreductasas , Shewanella/efectos de los fármacos , Shewanella/enzimología , Factores de Tiempo
14.
World J Transplant ; 14(1): 87532, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38576761

RESUMEN

Conditioning regimens employed in autologous stem cell transplantation have been proven useful in various hematological disorders and underlying malig nancies; however, despite being efficacious in various instances, negative consequences have also been recorded. Multiple conditioning regimens were extracted from various literature searches from databases like PubMed, Google scholar, EMBASE, and Cochrane. Conditioning regimens for each disease were compared by using various end points such as overall survival (OS), progression free survival (PFS), and leukemia free survival (LFS). Variables were presented on graphs and analyzed to conclude a more efficacious conditioning regimen. In multiple myeloma, the most effective regimen was high dose melphalan (MEL) given at a dose of 200/mg/m2. The comparative results of acute myeloid leukemia were presented and the regimens that proved to be at an admirable position were busulfan (BU) + MEL regarding OS and BU + VP16 regarding LFS. In case of acute lymphoblastic leukemia (ALL), BU, fludarabine, and etoposide (BuFluVP) conferred good disease control not only with a paramount improvement in survival rate but also low risk of recurrence. However, for ALL, chimeric antigen receptor (CAR) T cell therapy was preferred in the context of better OS and LFS. With respect to Hodgkin's lymphoma, mitoxantrone (MITO)/MEL overtook carmustine, VP16, cytarabine, and MEL in view of PFS and vice versa regarding OS. Non-Hodgkin's lymphoma patients were administered MITO (60 mg/m2) and MEL (180 mg/m2) which showed promising results. Lastly, amyloidosis was considered, and the regimen that proved to be competent was MEL 200 (200 mg/m2). This review article demonstrates a comparison between various conditioning regimens employed in different diseases.

15.
J Environ Manage ; 114: 372-80, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23176983

RESUMEN

Chlorpyrifos is a broad-spectrum insecticide which is used extensively in agriculture worldwide. Its massive application has led to the contamination of water and soil, and disruption of biogeochemical cycles. In addition, its residues have been detected in various ecological systems. A number of methods are currently available that can be used for the detoxification of such pesticides, however, this review focuses on microbial biodegradation which is considered to be one of the most viable options for the removal of organophosphate pesticides from the environment. Identification of genes and enzymes responsible for the cleavage of specific functional groups of the pesticide and understanding the kinetics of biodegradation are critical to accomplish successful bioremediation. Recently, the use of indigenous or genetically modified microorganisms and/or plants has increased the chances for in-situ bioremediation of contaminated sites. The literature provides evidence that the bioremediation process can be enhanced by maintaining an effective chlorpyrifos-degrading microbial community in the contaminated site and optimizing environmental conditions.


Asunto(s)
Cloropirifos/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Cinética , Consorcios Microbianos , Modelos Biológicos
16.
Environ Monit Assess ; 185(10): 8685-94, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23595691

RESUMEN

Urbanization can increase the vulnerability of soils to various types of contamination. Increased contamination of urban soils with polycyclic aromatic hydrocarbon (PAH) could relate to increased number of petrol pump stations and mechanical workshops-a phenomenon that needs to be constantly monitored. This study was undertaken to explore the soil PAH levels in Rawalpindi and Islamabad urban areas in relation to land use activities. Composite soil samples from petrol pump stations and mechanical workshops (n = 32) areas were evaluated for five PAHs--naphthalene, phenanthrene, pyrene, benzo[a]pyrene, and indeno(1,2,3-cd)pyrene-and compared with control area locations with minimum petroleum-related activity (n = 16). Surface samples up to 3 cm depth were collected and extraction of analytes was carried out using n-hexane and dichloromethane. Prior to running the samples, standards (100 µg ml(-1)) were run on HPLC to optimize signal to noise ratio using acetonitrile as mobile phase at a flow rate of 1.25 ml/min at 40 °C. Significant differences between petrol pump stations and mechanical workshop areas were observed for individual PAH as well as with control area soil samples. Naphthalene was found to be the most abundant PAH in soil, ranging from 2.47 to 24.36 mg kg(-1). Correlation between the benzo[a]pyrene (BaP) level in soil and the total PAH concentration (r = 0.82, P < 0.0001) revealed that BaP can be used as a potential marker for PAH pollution. A clear segregation between petrogenic and pyrogenic sources of contamination was observed when low molecular weight PAHs detected in soil was plotted against high molecular weight PAHs. The former source comprised lubricants and used engine oil found at mechanical workshops, whereas the latter could be mostly attributed to vehicular emission at petrol pumps. The results indicate that PAH contamination in urban areas of Rawalpindi and Islamabad has direct relevance with land use for petroleum activity. We conclude that in order to reduce the soil PAH exposure in urban environment, petrol pumps and mechanical workshops must be shifted to less densely populated areas because of their role as important point sources for PAH emission.


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes del Suelo/análisis , Suelo/química , Ciudades , Pakistán
17.
Appl Microbiol Biotechnol ; 96(6): 1599-606, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22290645

RESUMEN

Presence of huge amount of salts in the wastewater of textile dyeing industry is one of the major limiting factors in the development of an effective biotreatment system for the removal of azo dyes from textile effluents. Bacterial spp. capable of thriving under high salt conditions could be employed for the treatment of saline dyecontaminated textile wastewaters. The present study was aimed at isolating the most efficient bacterial strains capable of decolorizing azo dyes under high saline conditions. Fiftyeight bacterial strains were isolated from seawater, seawater sediment, and saline soil, using mineral salt medium enriched with 100 mg l−1 Reactive Black-5 azo dye and 50 g NaCl l−1 salt concentration. Bacterial strains KS23 (Psychrobacter alimentarius) and KS26 (Staphylococcus equorum) isolated from seawater sediment were able to decolorize three reactive dyes including Reactive Black 5, Reactive Golden Ovifix, and Reactive Blue BRS very efficiently in liquid medium over a wide range of salt concentration (0-100 g NaCl l)⁻¹. Time required for complete decolorization of 100 mg dye l ⁻¹ varied with the type of dye and salt concentration. In general, there was an inverse linear relationship between the velocity of the decolorization reaction (V) and salt concentration. This study suggested that bacteria isolated from saline conditions such as seawater sediment could be used in designing a bioreactor for the treatment of textile effluent containing high concentration of salts.


Asunto(s)
Compuestos Azo/metabolismo , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Colorantes/metabolismo , Sedimentos Geológicos/microbiología , Agua de Mar/microbiología , Cloruro de Sodio/metabolismo , Bacterias/clasificación , Bacterias/genética , Biodegradación Ambiental , Datos de Secuencia Molecular , Filogenia , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiología , Industria Textil
18.
Chemosphere ; 291(Pt 3): 132762, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34740700

RESUMEN

Bio-organic fertilizers (BIOs), prepared from inoculating plant growth-promoting rhizobacteria (PGPR) into agro-industrial wastes, are gaining more attention due to their tremendous positive effects on soil health. This study was conducted to prepare and evaluate the effect of bio-organic fertilizers on maize. Plant growth-promoting rhizobacteria were isolated from rhizospheric soil of farmer's field near Islamabad, Pakistan and were screened for plant growth promotion characters and one strain Burkholderia cenocepacia was selected based on PGPR's characteristics. In-vitro characterization, the whole genome sequence analysis, RAST and antiSMASH analysis were performed. The number of coding sequences was 7157 with the number of subsystems 382. The GC contents included 66.96%. The sequence was submitted to NCBI with BioProject submission number PRJNA730996. Inoculum of selected bacterial strain Burkholderia cenocepacia was used for carrying solid-state fermentation of organic wastes. Four different agro-industrial wastes with a good amount of crude protein were selected: black gram husks (BGH) (15-22% Crude protein CP), rice bran (RB) (10-15% CP), peanut shell (PS) (6-7% CP), and dry leaves (DL) (as conventional fertilizers for comparison) were collected, dried, ground and sieved. Different parameters like pH, moisture content, particle size, temperature etc. were optimized. Inductively coupled plasma - optical emission spectrometry (ICP-OES) analysis of bio-organic fertilizers was performed. In general, concentration of nitrogen was higher in the first three biofertilizers i.e. BGH, RB and PS as compared to DL. Germination and glasshouse experiments were conducted to evaluate the effect of four different BIOs on maize growth. The results showed that agro-industrial wastes inoculated with PGPR (BIOs) significantly enhanced (ϸ 0.05) germination percentage (100%) as compared to control (80%), whereas germination index, promptness index and seedling vigour index showed 32%, 34% and 21% increase respectively as compared to control. In the pot experiment, chlorophyll content increased by 28%, relative water content by 39.28%, protein by 3% and amino acid increased by 20.73% as compared to control. It was concluded that there is a positive effect of BIOs on germination parameters and the growth of maize. Thus, these BIOs can be recommended to farmers for the production of maize.


Asunto(s)
Burkholderia cenocepacia , Fertilizantes , Fermentación , Fertilizantes/análisis , Nitrógeno/análisis , Suelo
19.
PLoS One ; 17(1): e0262451, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35045121

RESUMEN

Climate change has been discussed as to exert shifts in geographical range of plants, animals or insect species by increasing, reducing or shifting its appropriate climatic habitat. Globally, Pakistan has been ranked at 5th position on the list of countries most vulnerable to climate change in 2020. Climate change has resulted in the losses of biodiversity and alteration in ecosystem as a result of depletion of natural habitats of species in Pakistan as well as in the world. Ants have been regarded as indicators of environmental change and ecosystem processes. Brachyponera nigrita (Emery, 1895) was reported for the first time from Pakistan (Pothwar region). Objective of our studies was to model geographic distribution of newly recorded ant species, B. nigrita based on two representative concentration pathways (RCP) (RCP4.5 and RCP8.5) for 2050s using maximum entropy model (Maxent) in Pakistan. In modeling procedure, 21occurrence records and 8 variables namely Bio4 (Temperature seasonality), Bio8 (Mean temperature of wettest quarter), Bio10 (Mean temperature of warmest quarter), Bio12 (Annual precipitation), Bio13 (Precipitation of wettest month), Bio15 (Precipitation seasonality), Bio17 (Precipitation of driest quarter) and Bio18 (Precipitation of warmest quarter) were used to determine the current and future distributions. Performance of the model was evaluated using AUC (area under curves) values, partial ROC, omission rates (E = 5%) and AICc (Model complexity).The results showed the average AUC value of the model was 0.930, which indicated that the accuracy of the model was excellent. The jackknife test also showed that Bio4, Bio18, Bio17 and Bio15 contributed 98% for the prediction of potential distribution of the species as compared to all other variables. Maxent results indicated that distribution area of B. nigrita under future predicted bioclimatics 2050 (RCP 4.5 and RCP8.5) would be increased in various localities of Pakistan as compared to its current distribution. In Pothwar region, moderately suitable and highly suitable areas of this species would increase by 505.932321km2and 572.118421km2as compared to current distribution under 2050 (RCP 4.5), while under 2050 (RCP 8.5), there would be an increase of 6427.2576km2and 3765.140493km2 respectively in moderately suitable and highly suitable areas of B. nigrita. This species was associated with termites, collembolans and larval stages of different insects. White eggs, creamy white pupae and many workers of this species were observed in a variety of habitats. Unknown nesting ecology, species identification characters supported with micrographs has been given which will help researchers for further ecological studies.


Asunto(s)
Hormigas/fisiología , Demografía/tendencias , Biomarcadores Ambientales/fisiología , Animales , Biodiversidad , Cambio Climático , Ecología , Ecosistema , Modelos Epidemiológicos , Geografía , Pakistán , Temperatura
20.
Plants (Basel) ; 11(17)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36079627

RESUMEN

Plant growth promoting (PGP) bacteria are known to enhance plant growth and protect them from environmental stresses through different pathways. The rhizosphere of perennial plants, including olive, may represent a relevant reservoir of PGP bacteria. Here, seven bacterial strains isolated from olive rhizosphere have been characterized taxonomically by 16S sequencing and biochemically, to evaluate their PGP potential. Most strains were identified as Pseudomonas or Bacillus spp., while the most promising ones belonged to genera Pseudomonas and Curtobacterium. Those strains have been tested for their capacity to grow under osmotic or salinity stress and to improve the germination and early development of Triticum durum subjected or not to those stresses. The selected strains had the ability to grow under severe stress, and a positive effect has been observed in non-stressed seedlings inoculated with one of the Pseudomonas strains, which showed promising characteristics that should be further evaluated. The biochemical and taxonomical characterization of bacterial strains isolated from different niches and the evaluation of their interaction with plants under varying conditions will help to increase our knowledge on PGP microorganisms and their use in agriculture.

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