Article
Engineering, Environmental
Bruno C. Marreiros, Monica Carvalheira, Claudia Henriques, Daniela Pequito, Yen Nguyen, Runar G. Solstad, J. Johannes Eksteen, Maria A. M. Reis
Summary: This study explores the potential of converting the proteinaceous fraction of fish silage into biodegradable polyhydroxyalkanoates (PHA), a more economically valuable product. The researchers conducted acidogenic fermentation of salmon peptone (SP) in a continuous reactor and obtained a fermentate rich in acetate and butyrate. The enriched mixed microbial culture with PHA-accumulating organisms achieved a good overall PHA yield and global volumetric PHA productivity, despite high ammonia concentration and constant nutrient availability.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Agricultural Engineering
Run-Ze Xu, Jia-Shun Cao, Jing-Yang Luo, Qian Feng, Bing-Jie Ni, Fang Fang
Summary: Integrating mechanistic and deep learning models can accurately predict the enrichment process of polyhydroxyalkanoates (PHA) accumulating bacteria (PAB) in mixed microbial cultures, aiding in optimizing the selection process for PHA production.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
Tania Palmeiro-Sanchez, Alison Graham, Piet Lens, Vincent O'Flaherty
Summary: By changing the temperature, different microbial communities were enriched in three reactors, resulting in different accumulation behaviors of polyhydroxyalkanoates (PHAs). The mesophilic reactor showed the best overall performance, with higher PHV fraction in the obtained copolymers.
WATER ENVIRONMENT RESEARCH
(2023)
Article
Mathematics, Applied
Stefan Awender, Renate Wackerbauer, Greg A. Breed
Summary: This study compares results and ecological interpretations from both generalized modeling and conventional dynamical systems modeling. The generalized model provides multiple possible dynamic scenarios and potentially conflicting results, while the specific model only provides a subset of stability data from the generalized model. Both approaches reveal that fixed points become stable when nutrient flows to predators are restricted and the basal growth rate approaches a maximum. The specific model also identifies a distinct ecosystem response to bottom-up forcing, where enrichment stabilizes a fixed point in a resource-deprived environment but destabilizes it when resources become more abundant. The generalized model provides less specific information but enables a powerful meta-analysis of uncertain complex systems.
Article
Agricultural Engineering
Fang Fang, Run-Ze Xu, Yan-Qiu Huang, Jing-Yang Luo, Wen-Ming Xie, Bing-Jie Ni, Jia-Shun Cao
Summary: The study found that N2O is an effective electron acceptor for PHA production, with the highest PHA yield and synthesis rate obtained using acetic acid as substrate. Low temperature and pH of 8.0 were beneficial for PHA accumulation. The thermogravimetric analysis showed that PHA produced with N2O as electron acceptor has better thermal stability.
BIORESOURCE TECHNOLOGY
(2021)
Article
Engineering, Environmental
Abdelrahman Amer, Younggy Kim
Summary: We developed innovative methods for rapid and selective enrichment of C. necator in mixed cultures, utilizing its unique metabolic characteristics. These methods showed promising results in the cost-effective cultivation of C. necator for PHA production.
ENVIRONMENTAL ENGINEERING SCIENCE
(2023)
Article
Green & Sustainable Science & Technology
Giovanna Pesante, Anna Zuliani, Elena Cannone, Francesca Greco, Chiara Tesoriero, Andrea Vettori, Nicola Frison
Summary: The study suggests the possibility of utilizing bacterial biomass produced from the conversion of zootechnical residues as an alternative protein source for fish feed in aquaculture. The results demonstrate that the microbial proteins generated through this process are a suitable replacement for commercially available feed, with improved survival rates when enriched with oils and polyhydroxyalkanoates.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Engineering, Environmental
E. G. F. Rezende, G. H. D. Oliveira, P. T. Couto, M. Zaiat, R. Ribeiro
Summary: Models were developed to represent the selection of PHA-producing microorganisms in a sequencing batch reactor (SBR) and the accumulation of PHA in a fed-batch reactor from sugarcane vinasse. Sensitivity analysis and optimization were conducted to understand the influence of parameters and operational conditions on PHA production. The results showed that higher CODt/Nitrogen ratios in the SBR favored the growth response rather than storage, shedding light on the impact of CODt/Nitrogen ratio on PHA accumulation.
JOURNAL OF WATER PROCESS ENGINEERING
(2023)
Article
Microbiology
Juliana R. Almeida, Joana C. Fradinho, Gilda Carvalho, Adrian Oehmen, Maria A. M. Reis
Summary: This work evaluates the influence of different operational conditions on the bacterial communities reported in phototrophic mixed culture (PMC) systems with polyhydroxyalkanoates (PHA) production capabilities. Chromatiaceae members were identified as the main phototrophic PHA producers, favored under high carbon concentrations and the permanent feast regime. Increasing the organic loading rate in systems fed with fermented wastewater enriched for other bacteria responsible for PHA storage. High-sugar feedstock impaired PHA production under the permanent feast conditions, but not under feast and famine conditions.
Article
Chemistry, Physical
Lorena Serrano-Gonzalez, Daniel Merino-Maldonado, Manuel Ignacio Guerra-Romero, Julia Maria Moran-del Pozo, Paulo Costa Lemos, Alice Santos Pereira, Paulina Faria, Julia Garcia-Gonzalez, Andres Juan-Valdes
Summary: The significant increase in world population has led to a large amount of construction waste and waste glycerol from transesterification reactions of oils, with limited recycling and management issues. Using crude glycerol as a carbon source, bioproducts derived from PHA-producing mixed microbial cultures were applied on concrete surfaces with recycled aggregate, effectively reducing water absorption and improving impermeability. This bioproduct offers a promising solution to protect concrete surfaces against water penetration, increasing durability and useful life.
Article
Energy & Fuels
Ibrahim Al Asmi, Kai Knobloch, Roman Le Goff Latimier, Thibaut Esence, Kurt Engelbrecht, Hamid Ben Ahmed
Summary: The potential of thermal storages in multi-energy networks is highlighted due to the increasing use of renewable energies. Meta modeling, based on simulation data from previous physical modeling, is proposed as an alternative to overcome the challenges of integrating physical models into the management of multi-energy networks. The developed meta model shows a significant reduction in calculation time compared to physical models while still providing accurate estimations.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Biochemical Research Methods
Rafaela A. P. Cruz, Adrian Oehmen, Maria A. M. Reis
Summary: This study demonstrates that removing excess biomass at the end of the famine phase results in significantly higher global PHA productivity, with volumetric biomass productivity being a key parameter affecting the overall PHA productivity of the 2-stage system. The results obtained offer important insights into maximizing PHA productivity and optimal operation of MMC systems.
Article
Mathematics
Valery Ochkov, Inna Vasileva, Ekaterina Borovinskaya, Wladimir Reschetilowski
Summary: This paper introduces an approach to build new classes of symmetric closed curves by generalizing classical definitions, and presents a universal numerical method for creating such curves in mathematical packages. It also discusses specific aspects of using B-splines for three-dimensional modeling in computer-aided design systems, demonstrating the applicability and high smoothness achievable with this method.
Article
Engineering, Electrical & Electronic
Petr Simek, Viktor Valouch
Summary: This paper introduces a new method for controlling the active and non-active instantaneous power of the grid-connected voltage source converter, known as Generalized Predictive Power Control (GPPC). The GPPC is a predictive control strategy for multi-input multi-output systems with time varying coefficients, offering benefits such as simple implementation, long prediction horizon, and resilience to parameter changes and unbalanced grid conditions. The method does not depend on the specific circuitry of the AC/DC converter or the Pulse Width Modulation (PWM) used, making it an original contribution to the field of controlling dc/ac converter performance.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2021)
Article
Ecology
Jadran Sessa, Dabeeruddin Syed, Ameema Zainab, Abdullah Hussein Al-Ghushami, Moaaz Ahmed
Summary: Researchers analyzed the microbial communities of different coral species in Australian waters and identified heat tolerance related genes in the core microbiome of corals.
ECOLOGICAL INFORMATICS
(2022)
Article
Environmental Sciences
Vania S. Bessa, Irina S. Moreira, Mark C. M. Van Loosdrecht, Paula M. L. Castro
Summary: The study found that the micropollutant diclofenac does not significantly affect wastewater treatment processes, but does impact the microbial community structure within the system. Integrated strategies are needed to reduce the spread of micropollutants in the environment.
ENVIRONMENTAL TECHNOLOGY
(2022)
Article
Ecology
Martin Pabst, Denis Grouzdev, Christopher E. Lawson, Hugo B. C. Kleikamp, Carol de Ram, Rogier Louwen, Yuemei Lin, Sebastian Lucker, Mark C. M. van Loosdrecht, Michele Laureni
Summary: The vast chemical diversity and strain variability of prokaryotic protein glycosylation pose significant challenges for large-scale exploration. A newly established mass binning glycoproteomics approach was used to uncover a variety of oligosaccharides in anaerobic ammonium-oxidizing bacterium Ca. Kuenenia stuttgartiensis, showing two seemingly unrelated biosynthetic routes and modulation related to energy metabolism. The study provides insights into the compositional exploration of prokaryotic protein glycosylation and showcases an example of the evolution of complex oligosaccharides in bacteria.
Article
Environmental Sciences
Lenno van den Berg, Mario Pronk, Mark C. M. van Loosdrecht, Merle K. de Kreuk
Summary: This study compared four methods to measure the density of granular sludge in a full-scale plant treating domestic sewage, and assessed the effect of salinity on granule density. Most methods yielded reliable results, as long as the effect of salinity was considered.
ENVIRONMENTAL TECHNOLOGY
(2023)
Editorial Material
Multidisciplinary Sciences
M-K H. Winkler, M. C. M. van Loosdrecht
Article
Environmental Sciences
Vojtech Kouba, Kamila Hurkova, Klara Navratilova, Dana Kok, Andrea Benakova, Michele Laureni, Patricie Vodickova, Tomas Podzimek, Petra Lipovova, Laura van Niftrik, Jana Hajslova, Mark C. M. van Loosdrecht, David Gregory Weissbrodt, Jan Bartacek
Summary: This study investigates the adaptation mechanisms of anammox bacteria to low temperatures. Shorter ladderane lipids were found to play a key role in low-temperature adaptation. Ca. Scalindua and Ca. Kuenenia exhibited different ladderane lipid profiles compared to Ca. Brocadia, suggesting their adaptability to low temperatures. Additionally, the study proposes new mechanisms, including ladderanes with absent phosphatidyl headgroup, for the low-temperature adaptation of anammox bacteria.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
S. de Bruin, D. Vasquez-Cardenas, S. M. Sarbu, F. J. R. Meysman, D. Z. Sousa, M. C. M. van Loosdrecht, Y. Lin
Summary: This study analyzed the presence of sGAG in acidophilic biofilm samples collected from Sulfur Cave in Romania. Results showed that the recovered sGAG had a structure similar to chondroitin and contained polysaccharides and sulfate. Genomic sequence analysis supported the hypothesis that sGAGs are synthesized by microbes within the biofilm.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Environmental
Xiaodi Hao, Wenbo Yu, Tugui Yuan, Yuanyuan Wu, Mark C. M. van Loosdrecht
Summary: This study aimed to determine the key factors controlling vivianite formation. The results showed that the amount of Fe3+ in WAS was the main factor controlling vivianite formation. In practice, a Fe/P molar ratio of 2:1 should be ensured for vivianite formation in AD.
Article
Engineering, Environmental
David Calderon-Franco, Roel Sarelse, Stella Christou, Mario Pronk, Mark C. M. van Loosdrecht, Thomas Abeel, David G. Weissbrodt
Summary: In the context of One Health, wastewater treatment plants play a crucial role in preventing the dissemination of antimicrobial resistance. However, current surveillance studies focus mainly on monitoring intracellular DNA, while the role of extracellular free DNA is often overlooked. This study found that in the process of wastewater treatment, the exDNA fractions containing resistance determinants and mobile genetic elements need to be considered for AMR surveillance and risk assessment.
Article
Engineering, Environmental
Laurence Strubbe, Edward J. H. van Dijk, Pascalle J. M. Deenekamp, Mark C. M. van Loosdrecht, Eveline I. P. Volcke
Summary: In the pursuit of reducing carbon footprint and energy costs, energy efficiency is crucial. This study focused on aerobic granular sludge reactors and found that they consume up to 50% less energy compared to conventional activated sludge systems. The study also investigated the dynamic behavior of the alpha factor and identified exchange ratio and temperature as the main influencing factors on its rate of increase during the aeration phase.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Sadiye Kosar, Onur Isik, Busra Cicekalan, Hazal Gulhan, Seyma Cingoz, Mustafa Yoruk, Hale Ozgun, Ismail Koyuncu, Mark C. M. van Loosdrecht, Mustafa Evren Ersahin
Summary: Achieving a neutral/positive energy balance without compromising discharge standards is a key goal in wastewater treatment plants. This study explores the coupling of high-rate activated sludge (HRAS) process with aerobic granular sludge (AGS) process as an energy-efficient pre-treatment option. The results show that feeding the AGS process with a mixture of HRAS process effluent and raw municipal wastewater can increase energy recovery potential and maintain high effluent quality.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Construction & Building Technology
Amir Tabakovic, Jeremy Lemmens, Jelmer Tamis, Dave van Vliet, Sayeda Nahar, Willem Suitela, Mark van Loosdrecht, Greet Leegwater
Summary: Bitumen is essential in asphalt pavements for its binding properties and ability to restore damage caused by traffic loading. With the decline in crude oil production, there is a need to find environmentally sustainable alternatives for bitumen modifiers. This paper investigates the potential use of the bio-based co-polymer PHBV as an alternative bitumen modifier and presents positive results from various tests.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Environmental
Navid Ahmadi, Mona Abbasi, Ali Torabian, Mark C. M. van Loosdrecht, Joel Ducoste
Summary: The transformation of four pharmaceuticals in a moving bed biofilm reactor was investigated under different COD/N ratios. Changes in the COD/N ratio influenced the competition between heterotrophic and nitrifying communities, resulting in shifts in microbial populations and composition in the biofilms. Autotrophic conditions exhibited higher transformation rates, indicating the importance of nitrification.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Materials Science, Characterization & Testing
Nam Kyeun Kim, Debes Bhattacharyya, Mark van Loosdrecht, Yuemei Lin
Summary: This research developed a bio-based flame retardant using a biopolymer derived from wastewater sludge to enhance the fire performance of polypropylene (PP). The study found that the extracellular polymeric substances (EPS) from wastewater sludge played a significant role in improving the char formation of PP composite. The incorporation of the bio-based flame retardant restricted the vertical burning characteristics of PP and improved its tensile moduli.
Article
Engineering, Environmental
T. Prot, W. Pannekoek, C. Belloni, A. Dugulan, R. Hendrikx, L. Korving, M. C. M. van Loosdrecht
Summary: The study found that vivianite can be efficiently formed in undigested activated sludge, and phosphorus recovery can be achieved without the use of a sludge digester. Additionally, recovering vivianite from undigested sludge can reduce waste disposal and mitigate vivianite scaling formation.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Microbiology
Sergio Tomas-Martinez, Le Min Chen, Thomas R. Neu, David G. Weissbrodt, Mark C. M. van Loosdrecht, Yuemei Lin
Summary: The catabolism of sialic acids in a microbial community resembles that of gut microbiota, indicating the importance of sialic acids in the absence of eukaryotic hosts.
FEMS MICROBIOLOGY ECOLOGY
(2022)
