Article
Agricultural Engineering
Rajesh J. Banu, G. Ginni, S. Kavitha, Yukesh R. Kannah, Adish S. Kumar, Shashi Kant Bhatia, Gopalakrishnan Kumar
Summary: Acidogenic fermentation is a key pathway for producing biohydrogen and short chain carboxylic acids, with the potential for producing additional value-added products. The application of a biorefinery can lead to efficient recovery of biofuels and value-added products, resulting in extra profits.
BIORESOURCE TECHNOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Danh H. Vu, Steven Wainaina, Mohammad J. Taherzadeh, Dan Akesson, Jorge A. Ferreira
Summary: The study demonstrates the potential of using VFAs from acidogenic fermentation of food waste as a cheap substrate for PHAs production, reducing production costs effectively; Bacillus megaterium can utilize VFAs for PHA production, and the use of VFAs mixture benefits bacterial growth.
Article
Green & Sustainable Science & Technology
E. Hosseini Koupaie, L. Lin, A. A. Bazyar Lakeh, A. Azizi, B. R. Dhar, H. Hafez, E. Elbeshbishy
Summary: The research found that coupling thermal hydrolysis (TH) and acidogenic fermentation can effectively increase the production of soluble organics in sludge, but it may reduce overall microbial diversity. Pre-hydrolysis achieved higher solubilization and VFAs production, and stimulated the growth of more kinetically efficient fermentative bacteria.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Biotechnology & Applied Microbiology
Nur Syakina Jamali, Jamaliah Md Jahim, Tabassum Mumtaz, Peer Mohamed Abdul
Summary: The study showed that Caldicellulosiruptor saccharolyticus performs well in hydrogen production using palm oil mill effluent, with the highest hydrogen productivity rates achieved under specific conditions. Immobilizing the bacteria on activated carbon shows promise in consistently achieving high hydrogen productivity rates in extreme thermophilic conditions.
ENVIRONMENTAL TECHNOLOGY & INNOVATION
(2021)
Article
Environmental Sciences
Gabriela Montiel-Jarillo, Teresa Gea, Adriana Artola, Javier Fuentes, Julian Carrera, Maria Eugenia Suarez-Ojeda
Summary: Acidogenic fermentation of wastes produces VFA-rich streams that can be used for PHA production. Heat-shock conditioning of inoculum proved to be more efficient for methanogens inhibition. The Winterization oil cake samples showed high propionic acid content, leading to significant PHA production without the need for additional carbon sources.
WASTE AND BIOMASS VALORIZATION
(2021)
Article
Biotechnology & Applied Microbiology
Farokh Laqa Kakar, Hussain Aqeel, Steven N. Liss, Elsayed Elbeshbishy
Summary: Four parameters affecting hydrothermal pretreatment (HTP) of municipal sludge were studied. The results showed that HTP parameters had significant effects on COD solubilization, VFA, and methane yield. HTP was found to increase COD solubilization and VFA production, leading to higher methane yield. The highest methane production yield was observed at high solid content, high pH, low temperature, and short retention time. HTP can be combined with other intensification routes to improve the fermentation and anaerobic digestion processes for waste treatment.
FERMENTATION-BASEL
(2023)
Article
Environmental Sciences
Borja Lagoa-Costa, Christian Kennes, Maria C. Veiga
Summary: The study aimed to investigate the microbial dynamics in response to a gradual change in feedstock composition during co-digestion of cheese whey and brewery wastewater, as well as its impact on PHA production. The results showed that the microbial community changed as the feedstock ratio gradually increased, leading to alterations in VFA profile and monomeric composition of the biopolymer.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Review
Chemistry, Physical
Safa Senan Mahmod, Shalini Narayanan Arisht, Jamaliah Md Jahim, Mohd Sobri Takriff, Jian Ping Tan, Abdullah Amru Indera Luthfi, Peer Mohamed Abdul
Summary: This study thoroughly investigates the treatment of palm oil mill effluent (POME) through closed dark fermentation (DF) system. Various enhancement methods for increasing hydrogen yield and improving process stability are discussed. Different pre-treatment methods and their effects on POME characteristics are reviewed. The study also examines different bioreactor designs and modifications applied to improve stability and productivity. The importance of further research towards a more inclusive and efficient POME treatment for biohydrogen production is emphasized.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Chemical
Apinya Singkhala, Chonticha Mamimin, Alissara Reungsang, Sompong O-Thong
Summary: The study showed that adjusting the pH of POME with oil palm ash significantly increased methane production, while biogas effluent recycling helped prevent pH drops, showing promising regulation effects.
Article
Engineering, Environmental
Elin Ossiansson, Frank Persson, Simon Bengtsson, Michael Cimbritz, David J. I. Gustavsson
Summary: This study investigated the primary treatment of municipal wastewater using rotating belt filtration followed by hydrolysis and acidogenic fermentation of the filter primary sludge (FPS) at ambient temperature for one year. The seasonal variations of VFAs, nutrient release, and soluble COD production, as well as microbial community assembly, were assessed, leading to novel findings for fermentation at ambient temperature.
Article
Engineering, Environmental
Luisa Niero, Fernando Morgan-Sagastume, Anders Lagerkvist
Summary: The study demonstrated the impact of temperature, pH, and retention time on the acidogenic fermentation of sewage sludge with wood fly ash added. Higher temperatures and adjusted pH favored hydrolysis, while fermentation producing organic acids was faster at lower temperatures.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Agricultural Engineering
A. Serra-Toro, S. Vinardell, S. Astals, S. Madurga, J. Llorens, J. Mata-Alvarez, F. Mas, J. Dosta
Summary: A gas-permeable membrane (GPM) contactor is a suitable technology to efficiently separate ammoniacal nitrogen and volatile fatty acids (VFA) from fermentation broths under different pH and temperature conditions.
BIORESOURCE TECHNOLOGY
(2022)
Article
Green & Sustainable Science & Technology
Lina Marcela Sanchez-Ledesma, Howard Ramirez-Malule, Jenny Alexandra Rodriguez-Victoria
Summary: This study conducted a bibliometric analysis of the scientific literature on volatile fatty acids (VFA) production from wastewater fermentation from 1981 to 21 June 2021. The analysis of 618 papers from the Scopus database using VOSviewer 1.6.16 software revealed that researchers have been exploring various approaches, including optimization of anaerobic digestion, biological removal of nutrients, energy production in bioelectrochemical systems, and recovery of VFA for different industries. The study also highlighted the importance of collaboration between scientific institutions in further research on wastewater treatment and VFA production.
Article
Biotechnology & Applied Microbiology
Kinanthi Mondylaksita, Jorge A. Ferreira, Wiratni Budhijanto, Claes Niklasson, Mohammad J. Taherzadeh, Ria Millati
Summary: The study demonstrates that high yields of volatile fatty acids can be obtained through fermentation of oil palm empty fruit bunch pretreatment products under conditions that inhibit methanogenesis, especially in a medium containing a mixture of glucan-rich and hemicellulosic compounds-rich fractions.
FERMENTATION-BASEL
(2021)
Article
Green & Sustainable Science & Technology
Muhammad Said, Andika Septian Sitanggang, Riski Julianda, Sri Pertiwi Estuningsih, Ahmad Fudholi
Summary: The study aimed to reduce BOD and COD values in aerobic fermentation process of POME by using a consortium of bacteria. Results showed a significant reduction in COD, BOD, and TSS values and production of methane in biogas during anaerobic fermentation process. High specific growth rate and low generation time were achieved, indicating effective degradation of organic and inorganic compounds in POME.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Engineering, Environmental
Yee-Sern Ng, Yee-Tong Tan, Adeline Seak May Chua, Mohd Ali Hashim, Bhaskar Sen Gupta
JOURNAL OF WATER PROCESS ENGINEERING
(2020)
Article
Engineering, Environmental
Thaothy Nguyenhuynh, Li Wan Yoon, Yin Hui Chow, Adeline Seak May Chua
Summary: Research has shown that utilizing a combination of mixed culture and carbon wastes for PHA production can reduce costs, with the selection of carbon feedstock and enrichment strategies being crucial. Current studies mainly apply the feast-famine regime for culture enrichment, showing comparable performance in terms of PHA content and yield with enriched culture, yet low productivity remains a hindering factor.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Environmental
Phiak Kim Poh, Ying Hui Ong, Krithika Arumugam, Tadashi Nittami, Hak Koon Yeoh, Irina Bessarab, Rohan William, Adeline Seak May Chua
Summary: This study investigated the effect of temperature on tropical inoculated EBPR systems, concluding that the system remained stable at 30 degrees Celsius with high P-removal efficiency. However, the system deteriorated at 40 degrees Celsius and the threshold temperature for tropical EBPR failure was found to be between 35 and 40 degrees Celsius.
WATER ENVIRONMENT RESEARCH
(2021)
Article
Polymer Science
Shiou Xuan Tan, Hwai Chyuan Ong, Andri Andriyana, Steven Lim, Yean Ling Pang, Fitranto Kusumo, Gek Cheng Ngoh
Summary: This study presents the preparation of chitosan reinforced starch-based bioplastic film by the solution casting and evaporation method. The effects of processing parameters on mechanical properties were examined and the results showed that the chitosan-reinforced starch-based bioplastic possessed good strength, elongation, thermal stability, and water resistance. It also exhibited a higher degradation rate compared to petroleum-based plastics.
Article
Polymer Science
Shiou Xuan Tan, Andri Andriyana, Hwai Chyuan Ong, Steven Lim, Yean Ling Pang, Gek Cheng Ngoh
Summary: Petroleum-based plastics pose environmental pollution problems due to their non-biodegradable and toxic properties, but renewable and biodegradable bioplastics have the potential to replace them. The fabrication of bioplastic films requires a delicate mixture of film-forming agents, plasticizers, and solvents. Research has focused on enhancing bioplastics' performance by using environmentally friendly nanoparticles. This review paper highlights the influencing factors on the properties of starch-based bioplastics and discusses their formation mechanism.
Article
Polymer Science
Shiou Xuan Tan, Andri Andriyana, Steven Lim, Hwai Chyuan Ong, Yean Ling Pang, Gek Cheng Ngoh
Summary: This study successfully optimized the extraction yield of sago starch using ultrasound assistance, resulting in a higher purity and swelling power of the extracted starch. The starch was further transformed into a bioplastic film with good mechanical properties and water vapor permeability, demonstrating its feasibility as a bioplastic material.
Article
Engineering, Environmental
Seow Wah How, Tadashi Shoji, Chee Keong Tan, Thomas P. Curtis, Adeline Seak May Chua
Summary: This study simulated and calibrated the low-DO OA process in tropical wastewater treatment plants based on the ASM1 model, revealing that the microbes in the low-DO OA SBR had lower growth rates and affinities, supporting the proliferation of nitrifiers under low-dissolved-oxygen conditions. The research emphasizes the importance of using suitable parameters in the design of wastewater treatment plants in tropical regions.
JOURNAL OF WATER PROCESS ENGINEERING
(2021)
Article
Engineering, Chemical
Li Wan Yoon, Ishrak Shariar Rafi, Gek Cheng Ngoh
Summary: This study investigates the potential of eliminating washing step in glucose recovery and ethanol production scheme when DES pretreatment is applied. The most suitable DES for pretreating sugarcane bagasse was found to be ChCl-MA, which resulted in high sugar recovery and low sugar loss during the process. The maximum amount of glucose recovered after 48 hours of enzymatic hydrolysis from both washed and unwashed pretreated substrate was insignificantly different, but slightly higher bioethanol was obtained from the unwashed pretreated substrate compared to the washed substrate.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Multidisciplinary Sciences
Morten Simonsen Dueholm, Marta Nierychlo, Kasper Skytte Andersen, Vibeke Rudkjobing, Simon Knutsson, Mads Albertsen, Per Halkjaer Nielsen
Summary: Microbial communities play a crucial role in biological wastewater treatment. This study generates a comprehensive 16S rRNA gene reference database using high-quality sequences from wastewater treatment plants worldwide, providing insights into the diversity and function of these microbial communities. The analysis reveals the impact of environmental conditions and biogeography on the activated sludge microbiota.
NATURE COMMUNICATIONS
(2022)
Article
Environmental Sciences
Jia Xing Loi, Adeline Seak May Chua, Mohamad Fairus Rabuni, Chee Keong Tan, Sai Hin Lai, Yasuyuki Takemura, Kazuaki Syutsubo
Summary: This study applied chemometrics to analyze water quality data from three major river basins in Selangor, Malaysia. The results showed spatial and periodic variations in pollution characteristics. Nitrogen species, total suspended solids, and dissolved solids were identified as the major pollution loads, with a significant increasing trend in ammonia pollution. The study highlights the vulnerability of Selangor's water resource system to water pollution and suggests incorporating ammonia treatment facilities into water treatment plants for smooth water supply operations.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Chemistry, Applied
Haliza Abdul Aziz, Rozita Yusoff, Ngoh Gek Cheng, Zainab Idris, Nur Aainaa Syahirah Ramli
Summary: The production cycle of heterogeneous catalyzed-transesterification for the production of esterquats precursor is considered as a cleaner and sustainable process. Reusing the catalyst reduces the formation of wastewater, consumption of toxic chemicals, and production costs.
JOURNAL OF SURFACTANTS AND DETERGENTS
(2023)
Article
Environmental Sciences
Chew Lee Leong, Seow Wah How, Mohamad Fairus Rabuni, Alijah Mohd Aris, Bee Chin Khor, Thomas P. Curtis, Adeline Seak May Chua
Summary: Conventionally, high DO concentrations are required for nitrification in biological nitrogen removal (BNR), making the process energy intensive. However, recent studies have shown that efficient ammonium removal and energy reduction can be achieved by operating nitrification at low DO concentrations. This study evaluated the feasibility of nitrogen removal from low COD/N tropical municipal wastewater using a low-DO oxic anoxic process. The results demonstrated high removal efficiency for ammonium and total nitrogen under low DO conditions, contributing to energy efficiency and sustainability.
Article
Environmental Sciences
Yuen Theng Cheong, Adeline Seak May Chua, Gek Cheng Ngoh
Summary: This study demonstrates the use of biodegradable deep eutectic solvent (DES) combined with assistive heating techniques for biomass pretreatment, resulting in an energy-efficient extraction. Sequential ultrasonic irradiation-microwave heating (UMAE) is found to be the most effective method for lignin extraction, achieving a delignification efficiency of 82.7% within 1 hour. The DES-incorporated UMAE method offers a 40% reduction in energy consumption and a 90% decrease in pretreatment duration compared to conventional methods.
WASTE AND BIOMASS VALORIZATION
(2023)
Article
Green & Sustainable Science & Technology
Seow Wah How, Choo Xiang Ting, Jing Ying Yap, Ching Yi Kwang, Chee Keong Tan, Wilasinee Yoochatchaval, Kazuaki Syutsubo, Adeline Seak May Chua
Summary: This study determined the optimal C/N ratio for biological nitrate removal and successfully demonstrated high-rate nitrate removal using an USB reactor, providing a promising technology for DWTPs to pre-treat raw water contaminated with nitrate.
SUSTAINABLE ENVIRONMENT RESEARCH
(2021)
Article
Chemistry, Physical
Wai Keng Teng, Rozita Yusoff, Mohamed Kheireddine Aroua, Gek Cheng Ngoh
Summary: Glycerol carbonate (GC) was successfully produced from industrial grade crude glycerol using calcium oxide (CaO) catalysis via microwave assisted transesterification (MAT). By optimizing reaction parameters, a high GC yield of 99.5% was achieved under specific conditions including a reaction temperature of 65 degrees C, reaction time of 3 min, and DMC/Gly molar ratio of 2.5.
SUSTAINABLE ENERGY & FUELS
(2021)
