Article
Engineering, Environmental
Ruizhe Pei, Gerard Vicente-Venegas, Agnieszka Tomaszewska-Porada, Mark C. M. Van Loosdrecht, Robbert Kleerebezem, Alan Werker
Summary: Polyhydroxyalkanoates (PHAs) can be produced from municipal waste activated sludge, but their distribution within microbial communities is limited. A selective staining method was developed to visualize the distribution of PHA storage activity and revealed that only a small fraction of the biomass was engaged in PHA accumulation. Optimized staining methods provided high acuity for imaging of PHA distribution and allowed for the distinction of different morphotypes within the biomass. These findings have important implications for PHA recovery methods and provide valuable insights for improving activated sludge processes.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Review
Agricultural Engineering
Laura De Donno Novelli, Sarah Moreno Sayavedra, Eldon R. Rene
Summary: The global issue of waste generation in the form of wastewater and solid wastes requires the development of sustainable treatment and resource recovery technologies. Researchers and process industries are interested in the value-added production of PHAs from industrial waste streams. By utilizing mixed microbial communities and carbon recovery techniques, PHA production could be more widely spread at the industrial scale.
BIORESOURCE TECHNOLOGY
(2021)
Review
Biochemistry & Molecular Biology
Bibi Nausheen Jaffur, Gopalakrishnan Kumar, Pratima Jeetah, Seeram Ramakrishna, Shashi Kant Bhatia
Summary: The current processes for producing PHAs are costly, but recent advances in functionalizing PHAs from waste streams offer opportunities for fostering a circular economy and waste reduction. This study focuses on developing sustainable and efficient methods, such as bioprocess engineering, catalysts, and materials science.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Microbiology
Athraa Alsaadi, Sree Selva Kumar Ganesen, Tan Suet May Amelia, Radwa Moanis, Eveline Peeters, Sevakumaran Vigneswari, Kesaven Bhubalan
Summary: Researchers have isolated and identified PHA-producing strains from sponge and sediment samples using cultivation and non-cultivation approaches. It was found that one strain showed previously unreported PHA-producing ability, and another strain showed the ability to synthesize 3-hydroxybutyrate without precursor addition.
Article
Green & Sustainable Science & Technology
Tirath Raj, K. Chandrasekhar, A. Naresh Kumar, Sang-Hyoun Kim
Summary: The rapid increase in disposal of fossil-derived single-use plastics has led to the accumulation of plastic waste and ecological imbalance. Developing alternative environmentally friendly, biodegradable, and biobased plastics using lignocellulosic biomass offers a sustainable solution. This review explores the potential of lignocellulosic biomass to produce biodegradable and recyclable plastics, highlighting pretreatment methods and challenges in the integrated biorefinery approach. The use of energy chemicals produced through biorefinery processes may serve as a precursor for sustainable bioplastics production. Various recyclable and biodegradable polymers are critically reviewed, and the limitations and future prospects of commercially available biorefinery industries are discussed.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Article
Polymer Science
Preeyaporn Injorhor, Tatiya Trongsatitkul, Jatuporn Wittayakun, Chaiwat Ruksakulpiwat, Yupaporn Ruksakulpiwat
Summary: Biodegradable polymers have important applications in medicine, particularly in internal devices, due to their ability to be broken down and absorbed into the body without producing harmful degradation products. In this study, biodegradable polylactic acid (PLA)-polyhydroxyalkanoate (PHA)-based nanocomposites with various PHA and nano-hydroxyapatite (nHAp) contents were prepared using solution casting method. The mechanical properties, microstructure, thermal stability, thermal properties, and in vitro degradation of the PLA-PHA-based composites were investigated. PLA-20PHA/5nHAp showed the desired properties and was successfully fabricated into fibers using electrospinning.
Article
Agricultural Engineering
Rijuta Ganesh Saratale, Si-Kyung Cho, Ganesh Dattatraya Saratale, Avinash A. Kadam, Gajanan S. Ghodake, Manu Kumar, Ram Naresh Bharagava, Gopalakrishnan Kumar, Dong Su Kim, Sikandar Mulla, Han Seung Shin
Summary: Polyhydroxyalkanoates (PHA) are considered as a promising alternative to replace synthetic plastics due to their comparable properties, and this review gives a comprehensive overview of current research focusing on the production of PHA from waste fluxes, providing insights for future research directions.
BIORESOURCE TECHNOLOGY
(2021)
Article
Biochemical Research Methods
Netsanet Gizaw Assefa, Hilde Hansen, Bjorn Altermark
Summary: Polyhydroxyalkanoates (PHAs) are natural biodegradable polyesters produced by microorganisms. This study identified and characterized a unique PHA biosynthesis enzyme, PhaC (BrPhaC), from a marine bacterium. Unlike other enzymes, BrPhaC is a trimeric enzyme without a lag phase and initiates enzymatic reaction instantly, regardless of temperature.
Article
Engineering, Environmental
James H. Wang, Yuchuan Tian, Bing Zhou
Summary: The study aimed to investigate the degradation behaviors of PBAT/PHA blend mulch films, adding UV stabilizer or antioxidant significantly improved the retention of mechanical properties, morphological evolution was studied by SEM, thermal properties and crystallinity analysis showed damage of crystalline structure during AAT, spectroscopic results indicated hydrolysis and photodegradative chain scissions.
JOURNAL OF POLYMERS AND THE ENVIRONMENT
(2022)
Article
Food Science & Technology
Sandhya Jayasekara, Lakshika Dissanayake, Lahiru N. Jayakody
Summary: This article discusses the potential of utilizing organic waste generated by the sugar industry to produce biodegradable smart/active polymer packaging materials for food applications. By leveraging microbial metabolism and metabolic engineering strategies, waste carbon can be efficiently transformed into platform chemicals such as lactic acid, succinate, and biopolymers, which can be used to produce biodegradable polymers like PBAT as alternatives to traditional polyethylene and polypropylene food packaging materials.
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
(2022)
Article
Biotechnology & Applied Microbiology
Samar Bacha, Fatma Arous, Emna Chouikh, Atef Jaouani, Maher Gtari, Khaled Charradi, Hamadi Attia, Dorra Ghorbel
Summary: This study evaluates bacterial strains isolated from olive oil mill wastewater for their ability to produce PHA, with Bacillus amyloliquefaciens strain OM81 showing promising results. The use of olive mill wastewater as a carbon source reduces production costs, and FTIR, DSC, and TGA analysis provide insights on the quality and characteristics of the produced PHA. This research contributes to reducing pollution and bioplastic production costs.
Article
Food Science & Technology
Phatthranit Klinmalai, Atcharawan Srisa, Yeyen Laorenza, Wattinee Katekhong, Nathdanai Harnkarnsujarit
Summary: Incorporating carvacrol into biodegradable polymers can produce functional sustainable packaging materials that prolong the shelf-life of food. The research shows that carvacrol-plasticized films have dense matrices and increased crystalline fractions, reducing permeability, delaying fungal growth, and increasing the shelf-life of packaged bread and cake.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Christopher M. Thomas, Deepak Kumar, Ryan A. Scheel, Bandaru Ramarao, Christopher T. Nomura
Summary: Biodegradable PHA biopolymers are a sought-after solution for plastic pollution. Market shifts driven by legislative pressures and changing consumer demands have led the packaging industry to seek alternative biopolymer solutions. The natural bacterial carbon storage polymer, PHAs, are interesting due to their marine biodegradability and ability to be made from waste resources, as well as their advantageous physical properties.
BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY
(2022)
Article
Polymer Science
Chang-Hwan Jeong, Sol-Hee Lee, Hack-Youn Kim
Summary: This study analyzes the food storage stability of biodegradable containers made of pork skin gelatin polymer and finds that containers containing up to 20% walnut shell powder can substitute plastic packaging materials.
Article
Biotechnology & Applied Microbiology
Victoria Saad, Bjoern Gutschmann, Thomas Grimm, Torsten Widmer, Peter Neubauer, Sebastian L. Riedel
Summary: Animal by-products separated by thermal hydrolysis were successfully screened as carbon sources for PHA production, with the Ralstonia eutropha Re2058/pCB113 strain accumulating high levels of PHA. Lowering PHA production costs could be achieved in the future by utilizing this method.
BIOTECHNOLOGY LETTERS
(2021)
Article
Biotechnology & Applied Microbiology
Bjoern Gutschmann, Matilde Maldonado Simoes, Thomas Schiewe, Edith S. Schroeter, Marvin Munzberg, Peter Neubauer, Anika Bockisch, Sebastian L. Riedel
Summary: Bioconversion of waste animal fat (WAF) to polyhydroxyalkanoates (PHAs) is an effective approach to reduce the production costs of plastic alternatives. In this study, a double-jacket feeding system was used to liquefy the WAF, resulting in increased PHA production compared to previous experiments with solid WAF. Real-time monitoring of growth and PHA formation was achieved through in-line photon density wave spectroscopy. The robustness of the process was evaluated in scale-down fermentations and the viability of cells was maintained even under periods of oxygen limitation.
MICROBIAL BIOTECHNOLOGY
(2023)
Article
Biotechnology & Applied Microbiology
Bjoern Gutschmann, Thomas H. Hoegl, Boyang Huang, Matilde Maldonado Simoes, Stefan Junne, Peter Neubauer, Thomas Grimm, Sebastian L. Riedel
Summary: Fat-containing animal by-product streams can be used as inexpensive substrates for biotechnological processes to enhance polyhydroxyalkanoate (PHA) bioplastic production. In this study, a fat/protein-emulsion (FPE) from pharmaceutical heparin production was successfully used as the sole carbon and nitrogen source for PHA production. This approach demonstrates the potential of valorizing animal by-product streams into PHA and contributes to a circular bioeconomy.
MICROBIAL BIOTECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Felix Kaspar, Felix Brandt, Sarah Westarp, Lea Eilert, Sebastian Kemper, Anke Kurreck, Peter Neubauer, Christoph R. R. Jacob, Anett Schallmey
Summary: Biocatalytic nucleoside (trans-)glycosylations catalyzed by nucleoside phosphorylases have become a practical method for preparing modified nucleosides, which are important in treating cancer and viral infections. However, the reaction yield is limited by the thermodynamic properties of the nucleosides, hindering access to desired target nucleosides. This study introduces a new approach by using inorganic borate to bias the esterification of nucleosides and ribosyl phosphates, thus affecting the apparent equilibrium in phosphorolysis and glycosylation reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Biotechnology & Applied Microbiology
Thomas Schiewe, Bjoern Gutschmann, Lara Santolin, Saskia Waldburger, Peter Neubauer, Roland Hass, Sebastian L. Riedel
Summary: Photon density wave (PDW) spectroscopy is a dilution-free method that allows independent quantification of light absorption and scattering with defined units. In this study, PDW spectroscopy was evaluated as a tool for real-time monitoring of biomass formation in E. coli cultivations. The results showed accurate correlation of PDW scattering coefficient with cell dry weight and direct detection of unintended process trends caused by overfeeding and acetate accumulation. Overall, inline PDW spectroscopy can contribute to more robust bioprocess monitoring and improved process performance.
BIOTECHNOLOGY AND BIOENGINEERING
(2023)
Article
Biochemistry & Molecular Biology
Isabel Thiele, Heba Yehia, Niels Krausch, Mario Birkholz, Mariano Nicolas Cruz Bournazou, Azis Boing Sitanggang, Matthias Kraume, Peter Neubauer, Anke Kurreck
Summary: Nucleoside analogues are important for treating viral infections or cancers. Continuous enzyme membrane reactors (EMRs) offer an alternative to batch enzymatic reactions, allowing for continuous production with integrated biocatalyst separation. The EMR demonstrated comparable specific productivities to batch reactions, but with significantly higher product per enzymatic unit for all nucleosides synthesized. This study validates the application of EMRs for nucleoside synthesis, reducing production costs and improving downstream processing.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biotechnology & Applied Microbiology
Lara Santolin, Isabel Thiele, Peter Neubauer, Sebastian L. L. Riedel
Summary: The microbially synthetized polyhydroxyalkanoate (PHA) copolymer poly(hydroxybutyrate-co-hydroxyhexanoate) [P(HB-co-HHx)] exhibits enhanced material properties that can replace various functions of petrochemical plastics. The thermal processability, toughness, and degradation rate of P(HB-co-HHx) can be modulated by adjusting its HHx molar content, allowing for customized polymer manufacturing. A simple batch strategy has been developed to precisely control the HHx content of P(HB-co-HHx) and obtain tailor-made PHAs with defined properties.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2023)
Article
Biotechnology & Applied Microbiology
Julia Schollmeyer, Saskia Waldburger, Kendra Njo, Heba Yehia, Anke Kurreck, Peter Neubauer, Sebastian L. Riedel
Summary: In this study, a suitable protocol for high cell density cultivations of ApMTAP was developed, and the highest yields of ApMTAP were obtained by growing at the maximum growth rate. Compared to shake flask cultivations, the volumetric yield of ApMTAP increased by a factor of 136. This study paves the way for the application of thermostable nucleoside phosphorylases in industrial settings.
BIOTECHNOLOGY AND BIOENGINEERING
(2023)
Article
Biotechnology & Applied Microbiology
Annina Kemmer, Nico Fischer, Terrance Wilms, Linda Cai, Sebastian Gross, Rudibert King, Peter Neubauer, M. Nicolas Cruz Bournazou
Summary: Robotic facilities have improved the speed and reliability of the bioprocess development pipeline. However, developing analytical technologies to cope with the throughput of cultivation systems remains challenging. In this work, a Sigma-Point Kalman Filter is implemented in a high throughput platform to demonstrate its viability and value in monitoring biomass concentration.
BIOTECHNOLOGY AND BIOENGINEERING
(2023)
Article
Biotechnology & Applied Microbiology
Michelle-Sophie Gerlach, Peter Neubauer, Matthias Gimpel
Summary: In order to obtain uniform and always equally fit precultures for inoculation of C. necator HP80, researchers have established an optimized protocol based on two subsequent precultures, reducing the preculture time to less than 30 h.
BIOTECHNOLOGY LETTERS
(2023)
Article
Chemistry, Physical
Mayara da Silva Santos, Robert Medel, Max Flach, Olesya S. Ablyasova, Martin Timm, Bernd von Issendorff, Konstantin Hirsch, Vicente Zamudio-Bayer, Sebastian Riedel, J. Tobias Lau
Summary: In this study, the researchers successfully produced and investigated the [RuO4](+) radical cation, which is a highly reactive oxidizing agent. By using X-ray absorption spectroscopy and quantum-chemical calculations, they discovered that [RuO4](+) is an oxygen-centered radical.
Article
Biotechnology & Applied Microbiology
Niels Krausch, Lucas Kaspersetz, Rogelio Diego Gaytan-Castro, Marie-Therese Schermeyer, Alvaro R. Lara, Guillermo Gosset, Mariano Nicolas Cruz Bournazou, Peter Neubauer
Summary: In this study, three different Escherichia coli knockout strains with limited glucose uptake capacities were characterized using a high-throughput robotic platform. The results showed that these mutant strains exhibited different growth characteristics and metabolic products under excess glucose conditions. Through a mechanistic mathematical model, comprehensive parameters were obtained, demonstrating the effectiveness of automated robotic equipment and mathematical modeling.
BIOENGINEERING-BASEL
(2023)
Article
Biotechnology & Applied Microbiology
Theresa Menzel, Peter Neubauer, Stefan Junne
Summary: In this study, two parallel plug-flow reactors were used for the hydrolysis stage of anaerobic pre-digestion of maize silage and recalcitrant bedding straw. The results showed that shorter hydraulic retention times (HRTs) improved the hydrolysis rate, while the hydrolysis yield remained similar. Longer HRTs led to metabolite accumulation and increased gas and acid production. Thin-sludge recirculation increased acid yield and stabilized the process, especially at shorter HRTs. Two main fermentation patterns were observed based on pH values, with different acids accumulating. The suitable combination of HRT and thin-sludge recirculation was found to be useful in a plug-flow hydrolysis process.
BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS
(2023)
Article
Microbiology
Vera Analise Schommer, Mateus Torres Nazari, Flavia Melara, Julia Catiane Arenhart Braun, Alan Rempel, Lara Franco dos Santos, Valdecir Ferrari, Luciane Maria Colla, Aline Dettmer, Jeferson Steffanello Piccin
Summary: This review introduces the techniques and mechanisms of bacteria immobilization on biochar, as well as its applications in bioremediation and agriculture. The immobilization characteristics of biochar depend on pyrolysis methods, raw materials, and properties of biochar. Scanning electron microscope and colony forming unit analysis are commonly used to verify the immobilization efficiency. Applying biochar-immobilized bacteria can improve soil quality, plant growth, and crop yield.
MICROBIOLOGICAL RESEARCH
(2024)
Article
Microbiology
Manoj Kumar Solanki, Naveen Chandra Joshi, Prashant Kumar Singh, Sandeep Kumar Singh, Gustavo Santoyo, Lucas Carvalho Basilio de Azevedo, Ajay Kumar
Summary: The rhizosphere microbiome plays a crucial role in plant growth and health. Rhizosphere engineering can be used to modify the microbiome and improve plant productivity and resilience.
MICROBIOLOGICAL RESEARCH
(2024)
Article
Microbiology
Xin Cao, Xing-Wang Cheng, Yin-Ying Liu, Hong-Wei Dai, Ren-You Gan
Summary: Maintaining oral health is crucial for overall well-being. Imbalances in oral microorganisms can lead to various infectious diseases. Exploring alternatives for prevention and management of oral infections is important due to limitations of current treatments. Natural products offer potential as reliable, effective, and affordable therapeutic options for oral infectious diseases.
MICROBIOLOGICAL RESEARCH
(2024)
Article
Microbiology
Jose David Flores-Felix, Ana Carolina Goncalves, Sara Meirinho, Ana Raquel Nunes, Gilberto Alves, Cristina Garcia-Viguera, Diego A. Moreno, Luis R. Silva
Summary: The application of bacterial biofortifiers is increasing and has been shown to improve the nutritional characteristics of blueberries in Portugal.
MICROBIOLOGICAL RESEARCH
(2024)
Review
Microbiology
Asma Sani, Wan-Qi Qin, Jia-Yi Li, Yi-Fan Liu, Lei Zhou, Shi-Zhong Yang, Bo-Zhong Mu
Summary: This article summarizes the structural diversity of microbial lipopeptide biosurfactants and their applications as biocontrol agents in plants. Lipopeptides have low toxicity and wide range of applications, making them important in the pesticide industry.
MICROBIOLOGICAL RESEARCH
(2024)
Article
Microbiology
Xiao-Yu Sun, Jie Deng, Chenhui Zhang, Sin-Yee Fung, Kam-Leung Siu, Ying-Ying Cheng, Liumei Ye, Jiaoxia Qin, Ke Wang, Jiu-Xin Qu, Wenying Gao, Fuxiang Wang, Dong-Yan Jin, Liang Yang
Summary: In this study, a novel c-di-GMP binding protein SodA that regulates oxidative stress tolerance in S. maltophilia was identified. The enzyme activity of SodA was shown to be directly modulated by c-di-GMP through various in vivo and in vitro experiments.
MICROBIOLOGICAL RESEARCH
(2024)
