Process optimization via response surface methodology in the physico-chemical treatment of vegetable oil refinery wastewater

Abstract

The present paper investigates the efficiency of coagulation/flocculation process using aluminum sulfate as coagulant and CHT industrial flocculent as coagulant aid/flocculent in the treatment of vegetable oil refinery wastewater (VORW). The process optimization was conducted in two steps, jar test experiments for preliminary evaluation to identify the most influencing factors and response surface methodology using Box–Behnken design to investigate the effects of three major factors and their interactions. The variables involved were the coagulant concentration (X₁), flocculent dosage (X₂), and initial pH (X₃) of water samples, while the responses were COD removal (Y1) and residual turbidity (Y2). The optimal conditions obtained by solving the quadratic regression models, as well as by analyzing the response surface contour plots, were as follows: 2.4 g/L of coagulant (aluminum sulfate), 60.05 mg/L of flocculent, and about 9.23 as initial pH. Under these conditions, the coagulation/flocculation treatment was able to achieve 99% of COD removal with total turbidity elimination (100% removal). Analysis of variance showed high variance coefficient (R²) values of 0.929 and 0.836 for COD and turbidity removals, respectively, thus ensuring a satisfactory adjustment of the second-order regression model with the experimental data. This statistical design methodology was demonstrated as an efficient and feasible approach for the optimization of coagulation/flocculation treatment.

New applied pharmacological approach/trend on utilization of agro-industrial wastes

Abstract

This study aimed to transform the locally available lignocellulosic residual palm frond (PF) and rice straw (RS) wastes into multifunction added products like methylated cellulose and sulfated and phosphorylated hemicelluloses by simple processes. Hydrolysis with 2 N sulfuric acid was the most suitable reaction for microcrystalline cellulose production. The characteristics of the prepared products were studied to obtain the optimum reaction conditions. Palm frond hemicellulose (PFHC) recorded the highest antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans (22, 22, 26 mm), respectively, and phosphorylated palm frond hemicellulose (PPFHC) exhibited the highest potential antioxidant activity of approximately 60%, suggesting a possible correlation between the two bioactivities. Most of extracted celluloses and their derivatives had a variety of promising probiotic activities which are expected to reduce the side effects of the gastric mucosa and possibly play a role in curing the gastric ulcer. Accordingly, the determination of anti-inflammatory and gastroprotective activity results revealed that methylcellulose, sulfated and phosphorylated hemicelluloses showed anti-inflammatory and gastroprotective activities and the capability of all tested compounds to ameliorate the ethanol-induced gastric ulcer in rats' stomach. All results recommended PF and RS and their derivatives to be used as a medicinal food.

CH 4 flux and methanogen community dynamics from five common emergent vegetations in a full-scale constructed wetland

Abstract

To investigate the effects of emergent plants on CH₄ efflux and elucidate the key factors responsible for these effects, annual monitoring of CH₄ emissions and methanogen community dynamics in a full-scale constructed wetland (CW) was conducted. Five emergent plants (Typha orientalis, Cyperus alternifolius, Arundo domax, Iris pseudacorus, and Thalia dealbata) commonly used in CWs were selected for investigation. The greatest CH₄ flux (annual mean 19.4 mg m⁻² h⁻¹) was observed from I. pseudacorus, while the lowest CH₄ flux (7.1 mg m⁻² h⁻¹) was observed from Thalia dealbata. The CH₄ flux from five emergent plants showed marked seasonal variation. Total nitrogen (TN) and total phosphorous (TP) were weakly correlated with CH₄ emissions, whereas total carbon (TC) and root biomass of plants were positively correlated with CH₄ emissions. Quantitative real-time PCR (q-PCR) analysis indicated that the gene abundance of eubacterial 16S rRNA, particulate methane monooxygenase (pmoA) and methyl coenzyme M reductase (mcrA) significantly differed among plant species. Differences in TC, root biomass, and dissolved oxygen (DO) caused by plant species were potential factors responsible for differences in methanogens, methanotrophs, and CH₄ emissions. Methanobacteriaceae, Methanoregulaceae, Methanomicrobiaceae, and Methanosarcinaceae were the dominant families of methanogens. The pathways of methanogenesis from the five emergent plants differed, with the main pathway being hydrogenotrophic, while both hydrogenotrophic and acetotrophic methanogens were involved in A. domax. Redundancy analysis (RDA) further indicated that emergent plant types had a profound influence on the methanogenic communities. Taken together, these results suggest emergent plant species can significantly influence CH₄ fluxes in CW through microbial communities, biochemical pathways for methanogenesis, TC, and DO. Furthermore, plant species in CWs should be considered an important factor in evaluating greenhouse gases emission. Finally, it is necessary to effectively manage CWs vegetation to maximize their environmental benefits.

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Reacciones cutáneas adversas a medicamentos: cómo identificar el desencadenante

Publication date: Available online 8 July 2018

Source: Actas Dermo-Sifiliográficas

Author(s): A. Zambernardi, M. Label

Resumen

Entre el 10 al 15% de los pacientes medicados desarrollan reacciones adversas a medicamentos (RAM). A pesar de la alta prevalencia de RAM, la identificación del agente causal es un desafío diagnóstico y terapéutico, principalmente en pacientes que reciben múltiples medicamentos. Nuestro objetivo es actualizar los métodos de diagnóstico para identificar el fármaco desencadenante de RAM de tipo B que comprometa piel y/o mucosas, a fin de optimizar el seguimiento y la calidad de vida del paciente. Desarrollamos la revisión en dos etapas: I- repasamos los mecanismos fisiopatológicos de las RAM; II- desarrollamos el abordaje clínico para la identificación del desencadenante.

Abstract

It is estimated that 10% to 15% of medicated patients develop adverse drug reactions (ADR). Despite the high prevalence of ADR, the identification of the trigger drugs remains a medical challenge, mainly in polymedicated patients. Our goal is to update the diagnostic tools to identify enhancer drugs of type B-ADR that compromise the skin and /or mucous membranes, in order to optimize patients' follow-up and improve their quality of life. We develop the review in two stages: I- we review the pathophysiological mechanisms of the ADR; II- we developed the clinical approach for the identification of the triggering drug.

Graphical abstract