Article
Ecology
Samridhi Rana, Arun Kumar
Summary: This study investigated the toxic effect of ZnO and CuO nanoparticles on freshwater microalgae. The results showed that the presence of a mixture of nanoparticles caused structural damage to the algae. In addition, the toxicity of the nanoparticles differed based on their concentration, with CuO nanoparticles showing the highest toxicity at low concentration and the mixture of nanoparticles showing antagonistic effects on the dry cell weight of the algae.
Article
Chemistry, Physical
Vasiliki D. Tsavatopoulou, Andriana F. Aravantinou, John Vakros, Ioannis D. Manariotis
Summary: The study evaluated the efficiency of biochar as a catalyst for converting lipids into biodiesel, with coffee spent grounds biochar performing the best at 400 degrees Celsius, and the pyrolysis temperature affecting the efficiency of the biochar.
Article
Green & Sustainable Science & Technology
Nikolaos Tzanakis, Andriana F. Aravantinou, Ioannis D. Manariotis
Summary: The aim of this study was to investigate the combined short-term toxic effect of zinc oxide (ZnO) nanoparticles (NPs) and nitrate concentration of the medium on freshwater microalgae. The results revealed that algal growth was affected by the exposure time, NPs concentrations, and mainly the initial nitrate concentration. The toxic effect of ZnO NPs was higher on microalgae cultured in modified BG-11 with low and high nitrate concentrations.
Article
Chemistry, Medicinal
Goncalo Espirito Santo, Ana Barros, Margarida Costa, Hugo Pereira, Mafalda Trovao, Helena Cardoso, Bernardo Carvalho, Maria Soares, Nadia Correia, Joana T. T. Silva, Marilia Mateus, Joana L. L. Silva
Summary: The main goal of this study is to find scalable ways to produce a highly concentrated biomass of Scenedesmus rubescens in heterotrophic conditions. By optimizing the medium through response surface methodology, the growth of Scenedesmus rubescens was improved by 3.2-fold at the lab-scale. Scale-up was then evaluated in a 7L stirred-tank reactor under fed-batch operation, resulting in an overall productivity of 8.63 g/L/day and a maximum biomass concentration of 69.5 g/L. The protein content of S. rubescens achieved approximately 31% of dry weight, similar to Chlorella vulgaris in heterotrophy.
Article
Engineering, Environmental
Bilal Ahmed, Asfa Rizvi, Asad Syed, Abdallah M. Elgorban, Mohammad Saghir Khan, Hind A. AL-Shwaiman, Javed Musarrat, Jintae Lee
Summary: The study revealed significant toxicity of ZnO-NPs, CuO-NPs, Zn2+, and Cu2+ on maize plants, especially under hydroponic conditions. These materials affect the growth and physiological functions of plants, and the translocation and distribution of nanoparticles in tissues were observed.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Environmental
Ping Wu, Peixin Cui, Huan Du, Marcelo Eduardo Alves, Dongmei Zhou, Yujun Wang
Summary: This study investigated the dissolution and transformation of ZnO nanoparticles in different soils and found that they rapidly dissolved in both acidic and near-neutral soils, transforming into stable forms. The results provide a better understanding of the fate of ZnO in soils and its potential for remediating ZnO-polluted soils.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Chemistry, Analytical
Yi Tang, Ying Huang, Hao-Yun Zou, Ling Wu, Zhong-Liang Xiao, Ju-Lan Zeng, Li-Xian Sun, Donghong Yu, Zhong Cao
Summary: In this study, hollow nanospheres of zinc oxide@cupric oxide (ZnO@CuO HNS) were successfully prepared and used to fabricate a thin-film gas sensor for hydrogen sulfide detection. The hollow nanocomposite exhibited excellent gas-sensing properties with low detection limit and fast response time. Additionally, the sensor showed good repeatability, selectivity, and stability, with pronounced long-term stability and run duration.
ANALYTICAL METHODS
(2022)
Article
Engineering, Environmental
Pu Wang, Lihong Zhao, Yuxiong Huang, Wei Qian, Xiaoshan Zhu, Zhenyu Wang, Zhonghua Cai
Summary: This study investigated the combined toxicity of nano-sized titanium dioxide (nTiO(2)) and cadmium (Cd2+) to the green alga Scenedesmus obliquus at different concentration ratios, revealing three different combined toxicity modes (antagonistic, partially additive, and synergistic). The concentration ratios of nTiO(2) to Cd2+ play a crucial role in determining the combined toxicity mode and provide insights for environmental and health risk assessment of co-exposure to conventional pollutants and MNMs.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Environmental Sciences
Pengyu Chen, Beibei Chen, Man He, Bin Hu
Summary: This study investigated the combined effect of zinc-based NPs and Cd2+ on HepG2 cells, finding that high-dose exposure reduced cell viability while low-dose exposure showed antagonism, with particle size having no significant impact on toxicity. Zinc ions increased cellular zinc content by upregulating transporter expression to manage ROS production, while zinc-based NPs decreased transporter expression to help maintain cell viability.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Nan Zhou, Huihui Liu, Xianhai Yang, Peter Watson, Feifei Yang
Summary: The COVID-19 pandemic has led to an increase in the use of iodinated contrast media (ICM), resulting in an increase in the presence of ICM-contaminated wastewater. The degradation of three typical ICM (iopamidol, iohexol, diatrizoate) under different conditions was investigated, and the potential acute toxicity of treated water containing ICM-derived disinfection byproducts (DBPs) on aquatic organisms was tested. The results showed that only iopamidol was significantly degraded by chlorination, and iohexol and diatrizoate were more rapidly degraded in chlorination with NH4+. Additionally, the disinfected water of iopamidol and iohexol treated with chlorination and NH4+ was found to be toxic to aquatic organisms. These findings highlight the potential ecological risk of ICM-containing wastewater and suggest that peracetic acid may be a more environmentally-friendly alternative for disinfection.
Article
Biochemistry & Molecular Biology
Soupam Das, Sayani Giri, Shinta Ann Jose, Mrudula Pulimi, Shalini Anand, N. Chandrasekaran, Pramod Kumar Rai, Amitava Mukherjee
Summary: This study investigated the toxicity of metal oxide nanoparticles (NPs) in mixtures using a freshwater microalga as a model organism. The results showed that dissolved ions in the nanoparticles mixtures contributed significantly to the toxicity. The binary and ternary mixtures of NPs exhibited higher toxic effects compared to individual entities. These findings highlight the importance of evaluating the combinatorial effects of metal oxide NPs.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Monica Pandey, Monika Singh, Kirti Wasnik, Shubhra Gupta, Sukanya Patra, Prem Shankar Gupta, Divya Pareek, Nyshadham Sai Naga Chaitanya, Somedutta Maity, Aramati B. M. Reddy, Ragini Tilak, Pradip Paik
Summary: In this study, mesoporous composite nanoparticles were synthesized and found to exhibit excellent antimicrobial activity against bacteria and fungi. Through computational docking methods, the interactions between the nanoparticles and microorganism-specific proteins were identified to explain their effectiveness. The composite nanoparticles show promise as stable inorganic antibiotics for use in healthcare technologies.
Article
Biophysics
Loredana F. Leopold, Cristina Coman, Doina Clapa, Ioana Oprea, Alexandra Toma, Stefania D. Iancu, Lucian Barbu-Tudoran, Maria Suciu, Alexandra Ciorita, Adrian I. Cadis, Laura Elena Muresan, Ioana Mihaela Perhaita, Lucian Copolovici, Dana M. Copolovici, Florina Copaciu, Nicolae Leopold, Dan C. Vodnar, Vasile Coman
Summary: This study evaluated the effects of large-scale TiO2 and ZnO nanoparticles on in vitro-grown soybean plants. The results showed that ZnO nanoparticles exhibited higher toxicity compared to TiO2, leading to negative effects on plant growth and metabolic processes.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2022)
Article
Environmental Sciences
Hongda Sun, Qingqing Peng, Jiao Guo, Haoyue Zhang, Junrui Bai, Hui Mao
Summary: This study investigated the effects of zinc oxide nanoparticles (NPs) on the growth of alfalfa and the soil environment. The results showed that high concentrations of ZnO NPs decreased the biomass and nitrogen-fixing ability of alfalfa, damaged root nodules and root tip cells, and reduced the abundance and diversity of soil microorganisms.
ENVIRONMENTAL POLLUTION
(2022)
Article
Environmental Sciences
Joyce Ribeiro Santos-Rasera, Regina Teresa Rosim Monteiro, Hudson Wallace Pereira de Carvalho
Summary: This study investigated the uptake, acute toxicity, and depuration of ZnO nanoparticles using the model fresh water organism Daphnia magna. The results showed that the toxicity of the nanoparticles depended on their size and the presence of surfactant. Contrary to previous reports, the study did not detect any depuration of ZnO nanoparticles after exposure.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Energy & Fuels
Vasiliki D. Tsavatopoulou, Andriana F. Aravantinou, Ioannis D. Manariotis
Summary: This study aimed to investigate the optimal transesterification method for biodiesel production from microalgae. Different algae species showed variations in the quality of produced biodiesel under different catalysts, with two-step processes yielding better results in some cases.
BIOMASS CONVERSION AND BIOREFINERY
(2021)
Article
Chemistry, Analytical
John Vakros, Ioannis D. Manariotis, Vassilios Dracopoulos, Dionissios Mantzavinos, Panagiotis Lianos
Summary: Activated carbon obtained from biomass wastes was processed into a high specific surface supercapacitor electrode, demonstrating good energy storage performance.
Article
Biotechnology & Applied Microbiology
Styliani E. Biliani, Ioannis D. Manariotis
Summary: In this study, the formation of algal flocs from activated sludge was investigated under static and stirring conditions using a synthetic substrate and secondary effluent from a wastewater treatment plant. The results showed that algal flocs were successfully developed in all cultures, with high chlorophyll concentration and efficient nutrient removal capability.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2022)
Article
Energy & Fuels
Vasiliki D. Tsavatopoulou, Ioannis D. Manariotis
Summary: This study examined the biofilm formation of Chlorococcum sp. and mixotrophic algae on different materials in horizontal and vertical positions. The results showed that patterned plexiglas performed better in terms of attachment for both Chlorococcum sp. and mixotrophic algae, regardless of their hydrophobicity, and the orientation of the materials played a crucial role in the attachment process.
BIOMASS CONVERSION AND BIOREFINERY
(2022)
Article
Engineering, Chemical
Spyridon Giannakopoulos, Zacharias Frontistis, John Vakros, Stavros G. Poulopoulos, Ioannis D. Manariotis, Dionissios Mantzavinos
Summary: In this study, biochars synthesized from spent coffee grounds were used in combination with solar irradiation or UV-A LED to activate sodium persulfate for the degradation of sulfamethoxazole in different water matrices. The results showed that high-temperature biochar with a large surface area was more efficient than low-temperature biochar with almost no surface area. The combined process exhibited synergy and could effectively remove sulfamethoxazole in a reasonable time frame.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2022)
Article
Electrochemistry
Rebecca Dhawle, John Vakros, Vassilios Dracopoulos, Ioannis D. Manariotis, Dionissios Mantzavinos, Panagiotis Lianos
Summary: A photocatalytic fuel cell has been developed with an added supercapacitor electrode for energy storage. The presence of the supercapacitor significantly increases hydrogen peroxide production, demonstrating the importance of energy storage functionality in practical applications.
ELECTROCHIMICA ACTA
(2022)
Article
Green & Sustainable Science & Technology
Spyridon Giannakopoulos, John Vakros, Vassilios Dracopoulos, Ioannis D. Manariotis, Dionissios Mantzavinos, Panagiotis Lianos
Summary: Biochar obtained from pyrolysis of spent malt rootlets and treatment with potassium hydroxide was used as a supercapacitor electrode and introduced as a third electrode in a photo-electrochemical cell. The dual property of biochar as a strong adsorber and supercapacitor significantly increased the degradation rate of the model pollutant.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Chemistry, Physical
Spyridon Giannakopoulos, John Vakros, Ioannis D. Manariotis, Dionissios Mantzavinos, Panagiotis Lianos
Summary: Biochar was obtained from spent malt rootlets through pyrolysis under limited oxygen supply and further activated by mixing with KOH and pyrolyzing again at high temperature. The activated biochar showed a total specific surface area of 1148 m(2) g(-1) and a micropore specific surface area of 690 m(2) g(-1). When used as an electrode in combination with a photoelectrochemical cell, the biochar electrode acted as a supercapacitor with a specific capacity of 98 Fg(-1), capable of storing and utilizing charges generated by the cell under both illuminated and dark conditions. Additionally, the same electrode exhibited electrocatalyst properties as an air-cathode, enabling oxygen reduction.
Article
Green & Sustainable Science & Technology
Styliani E. E. Biliani, John Vakros, Ioannis D. D. Manariotis
Summary: This study compared the performance of biochar from various food processing wastes for removing different nutrients from water, and found that modified biochar had higher adsorption capacity for nutrients.
Article
Chemistry, Physical
Spyridon Giannakopoulos, John Vakros, Zacharias Frontistis, Ioannis D. Manariotis, Danae Venieri, Stavros G. Poulopoulos, Dionissios Mantzavinos
Summary: Pyrolysis of lemon stalks at 850 degrees C under limited oxygen produces highly active and selective biochar that can activate persulfate ion and oxidize sulfamethoxazole (SMX). The biochar consists mainly of carbon and oxygen atoms, with calcium and potassium as the most abundant minerals. It has a moderate specific surface area of 154 m(2) g(-1) and contains carbonate species, possibly in the form of calcium carbonate. In ultrapure water, complete degradation of 0.5 mg L-1 SMX can be achieved within 20 minutes using 500 mg L-1 sodium persulfate (SPS) and 100 mg L-1 biochar. The biochar remains stable for at least five cycles and shows potential as a sustainable, metal-free catalyst.
Article
Engineering, Environmental
Leandros N. Sklivaniotis, Polychronis Economou, Hrissi K. Karapanagioti, Ioannis D. Manariotis
Summary: The aim of this study was to investigate the effectiveness of pyrolyzed low-cost food waste natural materials from the food industry in removing chlorine from water. Various biochars were produced and characterized, and continuous flow column experiments were conducted. The results showed that all materials tested were effective in removing free and total chlorine, with malt spent rootlets exhibiting the highest removal capacity.
ENVIRONMENTAL PROCESSES-AN INTERNATIONAL JOURNAL
(2023)
Review
Environmental Sciences
Dimitrios Kalderis, Azam Seifi, Trinh Kieu Trang, Toshiki Tsubota, Ioannis Anastopoulos, Ioannis Manariotis, Ioannis Pashalidis, Alireza Khataee
Summary: This review summarizes recent findings on the application of bamboo-based adsorbents in the removal of organic, inorganic, or gaseous pollutants. It discusses the preparation methods, surface modification methodologies, and effects on the adsorbent properties. The review also evaluates the adsorption capacities, mechanisms, and models for heavy metals, organics, and gaseous substances by bamboo-based adsorbents, and proposes directions for future research.
ENVIRONMENTAL RESEARCH
(2023)
Article
Biotechnology & Applied Microbiology
Vasiliki D. Tsavatopoulou, John Vakros, Ioannis. D. Manariotis
Summary: In this study, biochar produced from olive kernels pyrolyzed at 400 degrees C was tested as a solid support for adhering Chlorococcum sp. cultures. The culture containing 1 g L-1 biochar showed the best performance, resulting in 1.28 and 1.24 g microalgae g(-1) biochar in the presence and absence of nitrates, respectively. This study provides an alternative use of biochar to enhance microalgae growth and encourages its use as a supporting material in bioreactors.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2023)
Article
Environmental Sciences
Styliani E. Biliani, Ioannis D. Manariotis
Summary: Two raceway open ponds with volume of 5.5 liters each were used to assess the removal of organic material and nutrients from wastewater. Algal-bacterial flocs were utilized in the ponds to treat primary and secondary effluent. The hydraulic retention time gradually decreased from 5.5 to 2.2 days over a period of 21 days, and then both reactors operated at an HRT of 1.1 days. A high biomass concentration of around 2.2 g/L was sustained using primary and secondary effluent after 130 days. The biomass exhibited strong activity and could completely remove organic material and nutrients in less than 12 hours. Additionally, the algal-bacteria biomass had excellent settling properties, settling in less than 10 minutes.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Green & Sustainable Science & Technology
Nikolaos Tzanakis, Andriana F. Aravantinou, Ioannis D. Manariotis
Summary: The aim of this study was to investigate the combined short-term toxic effect of zinc oxide (ZnO) nanoparticles (NPs) and nitrate concentration of the medium on freshwater microalgae. The results revealed that algal growth was affected by the exposure time, NPs concentrations, and mainly the initial nitrate concentration. The toxic effect of ZnO NPs was higher on microalgae cultured in modified BG-11 with low and high nitrate concentrations.
