Reduction of DBP Precursors and Their THMFPs in Leachate Contaminated Groundwater by PAC Adsorption

This research investigated the reduction of dissolved organic matter (DOM) fractions and their trihalomethane formation potentials (THMFPs) by powder activated carbon (PAC) adsorption. Leachate contaminated groundwater around an inactive open-dumping landfill was selected as the raw water. The PAC adsorption reaction was proven to be the pseudo second order kinetic reaction and the Freundlich isotherm. The dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and THMFP removals were 55%, 57%, and 73%, respectively. The hydrophobic (HPO) fraction exhibited a higher THMFP compared to the hydrophilic (HPI) fraction. The results of DOM fractionation show that the use of PAC adsorption produced an efficient 87% reduction of the HPO fraction, which is characterized as having a high reactivity toward THMFP

Combined bioremediation and enzyme production by Aspergillus sp. in olive mill and winery wastewaters

Olive mill wastewaters (OMW) and vinasses (VS) are effluents produced respectively by olive mills and wineries, both sectors are of great economic importance in Mediterranean countries. These effluents cause a large environmental impact, when not properly processed, due to their high concentration of phenolic compounds, COD and colour. OMW may be treated by biological processes but, in this case, a dilution is necessary, increasing water consumption. The approach here in proposed consists on the bioremediation of OMW and VS by filamentous fungi. In a screening stage, three fungi (Aspergillus ibericus, Aspergillus uvarum, Aspergillus niger) were selected to bioremediate undiluted OMW, two-fold diluted OMW supplemented with nutrients, and a mixture of OMW and VS in the proportion 1:1 (v/v). Higher reductions of phenolic compounds, colour and COD were achieved mixing both residues; with A. uvarum providing the best results. In addition, the production of enzymes was also evaluated during this bioremediation process, detecting in all cases lipolytic, proteolytic and tannase activities. A. ibericus, A. uvarum and A. niger achieved the highest value of lipase (1253.7 ± 161.2 U/L), protease (3700 ± 124.3 U/L) and tannase (284.4 ± 12.1 U/L) activities, respectively. Consequently, this process is an interesting alternative to traditional processes to manage these residues, providing simultaneously high economic products, which can be employed in the same industries.Supported by the grant SFRH/BPD/84440/2012 and SFRH/BPD/43922/2008 respectively, from Fundação para a Ciência e Tecnologia – FCT, Portugal. Fundação para a Ciência e a Tecnologia (FCT) for financial support through the project FCT Pest-OE/EQB/LA0023/2011. Also, authors thank the Project “BioInd – Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028” Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDE

Structural insights into the production of 3-hydroxypropionic acid by aldehyde dehydrogenase from Azospirillum brasilense

3-Hydroxypropionic acid (3-HP) is an important platform chemical to be converted to acrylic acid and acrylamide. Aldehyde dehydrogenase (ALDH), an enzyme that catalyzes the reaction of 3-hydroxypropionaldehyde (3-HPA) to 3-HP, determines 3-HP production rate during the conversion of glycerol to 3-HP. To elucidate molecular mechanism of 3-HP production, we determined the first crystal structure of a 3-HP producing ALDH, alpha-ketoglutarate-semialdehyde dehydrogenase from Azospirillum basilensis (AbKGSADH), in its apo-form and in complex with NAD(+). Although showing an overall structure similar to other ALDHs, the AbKGSADH enzyme had an optimal substrate binding site for accepting 3-HPA as a substrate. Molecular docking simulation of 3-HPA into the AbKGSADH structure revealed that the residues Asn159, Gln160 and Arg163 stabilize the aldehyde-and the hydroxyl-groups of 3-HPA through hydrogen bonds, and several hydrophobic residues, such as Phe156, Val286, Ile288, and Phe450, provide the optimal size and shape for 3-HPA binding. We also compared AbKGSADH with other reported 3-HP producing ALDHs for the crucial amino acid residues for enzyme catalysis and substrate binding, which provides structural implications on how these enzymes utilize 3-HPA as a substrate

Ultrasound irradiation in the production of ethanol from biomass

Ethanol produced from renewable biomass, such as lignocellulosic feedstock, is one of the alternative energy resources that can be environmentally friendly. However, physical and chemical barriers caused by the close association of the main components of lignocellulosic biomass, as well as starch, hinder the hydrolysis of cellulose and hemicellulose in lignocellulose as well as amylase and amylopectin in starch to fermentable sugars. One of the main goals of pretreatment for enzymatic hydrolysis is to increase the enzyme accessibility for improving digestibility of cellulose and starch. Ultrasound irradiation applied to cellulosic materials and starch-based feedstock was found to enhance the efficiency of hydrolysis and subsequently increase the sugar yield. Prior research conducted on applying ultrasonic technology for cellulose and starch pretreatment has considered a variety of effects on physical and chemical characteristics, hydrolysis efficiency and ethanol yield. This paper reviews the application of ultrasound irradiation to cellulose and starch prior to and during hydrolysis in terms of sugar and ethanol yields. It also addresses characteristics such as accessibility, crystallinity, degree of polymerization, morphological structure, swelling power, particle size and viscosity as influenced by ultrasonic treatment. © 2014 Elsevier Ltd

Recent developments in the production of liquid fuels via catalytic conversion of microalgae: experiments and simulations

Due to continuing high demand, depletion of non-renewable resources and increasing concerns about climate change, the use of fossil fuel-derived transportation fuels faces relentless challenges both from a world markets and an environmental perspective. The production of renewable transportation fuel from microalgae continues to attract much attention because of its potential for fast growth rates, high oil content, ability to grow in unconventional scenarios, and inherent carbon neutrality. Moreover, the use of microalgae would minimize ‘‘food versus fuel’’ concerns associated with several biomass strategies, as microalgae do not compete with food crops in the food chain. This paper reviews the progress of recent research on the production of transportation fuels via homogeneous and heterogeneous catalytic conversions of microalgae. This review also describes the development of tools that may allow for a more fundamental understanding of catalyst selection and conversion processes using computational modelling. The catalytic conversion reaction pathways that have been investigated are fully discussed based on both experimental and theoretical approaches. Finally, this work makes several projections for the potential of various thermocatalytic pathways to produce alternative transportation fuels from algae, and identifies key areas where the authors feel that computational modelling should be directed to elucidate key information to optimize the process

Protein-rich fungal biomass production on sugarcane vinasse for animal feed applications with concomitant water reclamation

Ph.D. University of Hawaii at Manoa 2012.Includes bibliographical references.The sugar-to-ethanol production process generates a significant amount of lowvalue residue known as vinasse. Vinasse has a high organic content measured as chemical oxygen demand (COD) of over 100 g/L, and its direct disposal has a negative impact on the environment. This research investigated the feasibility of fungal technology as a cost effective and environment-friendly approach in utilizing the vinasse as a sole substrate for producing a protein-rich edible fungus, Rhizopus microsporus (var. oligosporus) with concomitant wastewater reclamation. Optimization studies showed prolific fungal growth at pH 5.0 on vinasse with nutrient (nitrogen and phosphorus) supplementation. The fungus grew exponentially during the first 24 hours using reducing sugar as a major constituent to support its growth. Ethanol at concentrations greater than 5.0% (v/v) adversely affected the fungal growth through change in mycelial morphology. Fungal fermentation in an airlift bioreactor (2.5-L working volume) under various aeration rates (0.5, 1.0, 1.5, and 2.0 volumeair/volumeliquid/min (vvm)) was investigated for the potential large-scale fungal biomass production. The fungal biomass yield was found to depend on the aeration rate, and the aeration rate of 1.5 vvm resulted in the highest fungal biomass yield of 8.04 ± 0.80 (gbiomass increase/ginitial biomass) with significant reduction in organic content ~ 80% (or 26 g/L) measured as soluble chemical oxygen demand (SCOD). Vinasse-derived fungal biomass contained approximately 50% crude protein with 84% in vitro protein digestibility. Essential amino acids contents of the fungal biomass were comparable to commercial protein sources (fishmeal and soybean meal) for animal feeds, with the exception of methionine and phenylalanine. Importantly, the fungal biomass contained high lysine (~ 8% on protein basis), which is the most critical amino acid required in animal feed. Moreover, fungal biomass had essential fatty acids including linoleic, linolenic, eicosapentaenoic (EPA), and docosahexaenoic (DHA), which could further benefit fungal biomass as an aquatic feed. The integration of innovative fungal technology with sugar-based ethanol production could provide an opportunity for producing food-grade fungal protein for animal feed application with simultaneous wastewater reclamation for in-plant use or for land applications

Idiopathic Sporadic Onychomadesis of Toenails

Onychomadesis is a clinical sign of nail plate separation due to transient or permanent arrest of nail matrix activities. Onychomadesis can be considered as a severe form of Beau’s line. This condition usually occurs after trauma, causal diseases, or medications, yet it rarely occurs as an idiopathic condition. We report a case of a 38-year-old Thai female who developed recurrence onychomadesis in several toenails in the absence of predisposing factors or associated conditions. To the best of our knowledge, our patient is the first reported case of idiopathic onychomadesis limited to toenails

Intralesional Botulinum Toxin A Injection for Recalcitrant Alopecial Totalis and Alopecia Universalis: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Alopecia totalis (AT) and alopecia universalis (AU) have a high rate of recurrence and are very difficult to treat. To date, no consensus has been reach among clinicians regarding the best way to treat these conditions. It was recently proposed that botulinum toxin type A (BT) injection in alopecia areata may inhibit unmyelinated C fibers from releasing substance P and calcitonin-gene-related protein (CGRP), which showed a favorable clinical response in cephalalgic alopecia areata. Objective: To investigate the efficacy of botulinum toxin type A (BT) in the treatment of recalcitrant AT and AU. Methods: Twenty patients with either recalcitrant AT or AU were enrolled in this study. One half of the scalp was injected with BT 50 units 2.5 ml intradermally (dilution 20 units/ml) and the other half of the scalp was injected with normal saline 2.5 ml. Clinical assessments were performed using Severity of Alopecia Tool (SALT) score, scalp mapping, and photography. Patients were followed up monthly for 4 months after treatment to evaluate terminal hair regrowth. Results: Based on patient results at the 4-month follow-up, no clinical improvement in either recalcitrant alopecia totalis or alopecia universalis was observed. Conclusion: Although BT has been demonstrated to improve the clinical features of cephalalgia alopecia areata, BT was not shown to improve the clinical features of recalcitrant AT or AU in this study. In order to understand and explain the differences in these two clinical outcomes using BT in alopecia, further investigation is needed