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Yeasts are the usual contaminants in fruit juices and other beverages, responsible for the decrease in the quality and shelf-life of such products. Preservatives are principally added to these beverages to enhance their shelf-life. With the increasing consumer concern towards chemical food additives, plant-derived antimicrobials have attracted the attention of researchers as efficient and safer anti-yeast agents. However, the methods currently used for determining their anti-yeast activity are time- and material-consuming. In this study, the anti-yeast effect of plant phenolic compounds in apple and orange juice food models using microtiter plates has been evaluated in order to validate the modified broth microdilution method for screening the antimicrobial activity of juice preservative agents. Among the twelve compounds tested, four showed a significant in vitro growth-inhibitory effect against all tested yeasts (Saccharomyces cerevisiae, Zygosaccharomyces bailii, and Zygosaccharomyces rouxii) in both orange and apple juices. The best results were obtained for pterostilbene in both juices with minimum inhibitory concentrations (MICs) ranging from 32 to 128 μg/mL. Other compounds, namely oxyresveratrol, piceatannol, and ferulic acid, exhibited moderate inhibitory effects with MICs of 256–512 μg/mL. Furthermore, the results indicated that differences in the chemical structures of the compounds tested significantly affected the level of yeast inhibition, whereas stilbenes with methoxy and hydroxy groups produced the strongest effect. Furthermore, the innovative assay developed in this study can be used for screening the anti-yeast activity of juice preservative agents because it saves preparatory and analysis time, laboratory supplies, and manpower in comparison to the methods commonly used. [ABSTRACT FROM AUTHOR]

The migration of heavy metals and radionuclides is interrelated, and this study focusses on the interaction and complex influence of various toxicants. The rehabilitation of radioactively contaminated territories has a complex character and is based on scientifically supported measures to restore industrial, economic, and sociopsychological relations. We aim for the achievement of pre-emergency levels of hygienic norms of radioactive contamination of output products. This, in its sum, allows for further economic activity in these territories without restrictions on the basis of natural actions of autoremediation. Biosorption technologies based on bacterial biomass remain a promising direction for the remediation of soils contaminated with radionuclides and heavy metals that help immobilise and consolidate contaminants. A comprehensive understanding of the biosorption capacity of various preparations allows for the selection of more effective techniques for the elimination of contaminants, as well as the overcoming of differences between laboratory results and industrial use. Observation and monitoring make it possible to evaluate the migration process of heavy metals and radionuclides and identify regions with a disturbed balance of harmful substances. The promising direction of the soil application of phosphogypsum, a by-product of the chemical industry, in bioremediation processes is considered. [ABSTRACT FROM AUTHOR]

The purpose of our research is to evaluate the agroecological condition of soils under long-term irrigation (over 50 years) and to improve existing measures to slow down degradation processes by introducing phosphogypsum. The possibility of simultaneously addressing the ecological issue of using large amounts of phosphogypsum waste and the agronomic characteristics of slowing or eliminating salinisation processes in irrigated soils has been studied and justified. The research methodology was based on the comparison of different meliorative doses of phosphogypsum under the following conditions: by the amount of exchangeable sodium that should displace calcium in the calculated soil layer; by the coagulation limit; and by the absorption norm and the corresponding amount of sodium coming with irrigation water. To determine water-soluble salts (anions, cations) and pH level, a water extract was utilized. Multi-year studies to determine the impact of phosphogypsum on irrigation-salinised soils with and without irrigation showed positive changes in the anion–cation composition of water extraction, resulting in a reduction in the degree of the salinity of these soils. It was established that in chernozem soils under irrigation, the sodium adsorption ratio decreases by 74.5% compared to the control indicators, and without irrigation, by 23%. The best results in the displacement of exchangeable sodium were observed when phosphogypsum was applied at a dose calculated by the coagulation limit without irrigation and with irrigation—by the absorption norm. [ABSTRACT FROM AUTHOR]

This study aimed to improve the control system of the biological stage of wastewater treatment using the quality control information system to support the concept of environmental efficiency management. In this case, the object of the study was the treatment facilities of Sumy city (Ukraine). For automatic control of wastewater quality, pH, oxidation reduction potential (ORP), electrical conductivity, and temperature indicators were taken, as well as hydrobiological analysis of activated sludge and mathematical modelling. The pH of wastewater at the input system has systematically unacceptable values (above 8.5 were recorded). Unacceptable concentrations of sulphur-containing toxicants arrive at the entrance of treatment facilities (0.22–1.3 mg/L). The response of activated sludge biocenosis to increasing concentrations of hydrogen sulphide in wastewater was analysed. Furthermore, a mathematical model of monoculture population growth, with two factors that affect population growth (nutrient concentration and monoculture production concentration), was implemented for the initial assessment of possible negative effects on wastewater treatment. The differential equation of the population dynamics of the i-th species of microorganisms in activated sludge was described. The applied system of automated monitoring of wastewater parameters with expert assessment of activated sludge and a unified mathematical model of approaches allows for a complex system of decision-making support to be realised. However, this requires the construction of mathematical models that would take into account the cause–effect relations that operate under conditions of incomplete technological information and the potential presence of emergencies due to natural disasters and military activities. [ABSTRACT FROM AUTHOR]

Biogas technology has the potential to achieve at least eight of the Sustainable Development Goals (SDGs). This study assessed household biogas consumption against firewood and its socioeconomic and environmental impacts with regard to achieving the SDGs in the Iganga District, Uganda. In addition, factors hindering the adoption of biogas technology were assessed. Data were collected from 314 respondents using a questionnaire, interview, and observation. A mixed analytical approach combined descriptive analysis, multivariate analysis of variance and one-way analysis of variance tests to compare the impacts of biogas and firewood use and identify factors hindering the adoption of biogas technology. Results show that biogas consumption contributed to higher socioeconomic, health and environmental benefits than firewood. Biogas positively impacted SDG7, and indirectly, SDGs 2, 3, 5, 6, 8, 9, and 13. An estimated 46.9% of households perceive biogas as a clean fuel. The factors motivating biogas consumption include its smoke-free nature, women and children having more time to engage in other development activities and reduced time spent on cooking. In conclusion, biogas offers higher impacts on SDGs compared to firewood. Reviewing the current national renewable energy promotion frameworks to provide biogas subsidies to households and investors can contribute to increasing biogas consumption in households. [ABSTRACT FROM AUTHOR]

By 2025, biogas is estimated to become a larger part of Indonesia's energy mix. Biogas is a renewable energy source that also has economic and environmental advantages. Domestic biogas generation has been embraced in Indonesia as a response to the country's energy security concerns in rural areas. Since the 1970s, 48,038 biogas plants have been built in the region. To fully develop this technology, Indonesia must discontinue relying on fossil fuels and substitute current fossil-fuel-based energy. This article provides an overview of renewable technology in Indonesia, as well as addressing domestic energy demands and referring to existing literature on the socio-technical and socio-economic barriers to biogas adoption in Indonesia. Based on a rigorous review of 71 publications published in Web of Science (WoS) between 2010 and 2021, this study explores existing barriers for biogas adoption by summarizing the current literature from technical, economic, social and environmental perspectives. Biogas adoption is a complex process with many interwoven components. Therefore, this research addresses a gap in the strategic planning and implementation process, providing policymakers with pathways to eliminate bottlenecks in renewable energy planning. Recommendations for future research are also proposed. [ABSTRACT FROM AUTHOR]

The problem of recycling and storage of phosphogypsum is topical for many countries around the world, as it is associated with environmental problems of pollution of water bodies, land, and atmosphere. Therefore, this paper analyzes the directions of phosphogypsum recycling and possible alternatives to its use. The main disadvantages of the existing methods of phosphogypsum processing were identified and trends in this waste management were also considered. Through the VOSviewer programme, a visualization of cluster interconnections was carried out in research publications of various fields of phosphogypsum utilization. Five clusters were formed: a red cluster—phosphogypsum recycling in the construction industry; green cluster—radiation pollution problem of phosphogypsum and phosphate fertilizers; yellow cluster—monitoring migration of phosphogypsum components in the ecosystem, with the mobile forms of heavy metals and their inflow into aquifers from phosphogypsum dumps; blue cluster—use of phosphogypsum in agriculture as an ameliorant and a component of fertilizer; and a purple cluster—the impact of phosphogypsum on microorganisms, particularly in bioremediation processes. Under the proposed integrated biochemical approach, the use of various bioprocesses of phosphogypsum recovery from waste dumps and implementation of new biotechnological solutions for processing phosphorus raw materials are presented. [ABSTRACT FROM AUTHOR]

Within developing countries, there is an appeal to use waste biomass for energy generation in the form of bio-briquettes. This study investigated the potential use of bio-briquettes that are produced from the waste biomass of the following tropical fruits: durian (Durio zibethinus), coconut (Cocos nucifera), coffee (Coffea arabica), cacao (Theobroma cacao), banana (Musa acuminata) and rambutan (Nephelium lappaceum). All fruit waste biomass samples exhibited an extremely high level of initial moisture content (78.22% in average). Fruit samples with the highest proportion of fruit waste biomass (of total unprocessed fruit mass) were represented by cacao (83.82%), durian (62.56%) and coconut (56.83%). Highest energy potentials (calorific value) of fruit waste biomass were observed in case of coconut (18.22 MJ•kg-1), banana (17.79 MJ•kg-1) fruit samples, whereas fruit waste biomass with the lowest level of ash content originated from the rambutan (3.67%), coconut (4.52%), and durian (5.05%) fruit samples. When investigating the energy demands to produce bio-briquettes from such feedstock materials, the best results (lowest amount of required deformation energy in combination with highest level of bio-briquette bulk density) were achieved by the rambutan, durian and banana fruit waste biomass samples. Finally, all investigated bio-briquette samples presented satisfactory levels of bulk density (>1050 kg•m-3). In conclusion, our results indicated the practicability and viability of such bio-briquette fuel production, as well as supporting the fact that bio-briquettes from tropical fruit waste biomass can offer a potentially attractive energy source with many benefits, especially in rural areas. [ABSTRACT FROM AUTHOR]

Due to high levels of volatility in both the agricultural and the forestry commodity markets, specifically, of timber and agricultural crops, it is important to identify the risks associated with the stability of supplies necessary for the production of composite materials in the Czech Republic. This study aims to accurately estimate the availability of selected raw materials that contain lignocellulose over the next 20 years. In addition, their suitability for the production of composite materials is assessed based on their physical properties. Furthermore, in the event of scarcity involving timber in the European Union, recycled wood and post-harvest residues could replace conventional raw materials in wood-based composites such as particleboards and chipboards. The viable potential of Czech forests is predicted to be between 740 and 750 million cubic meters of timber. For agricultural crops, it is estimated at 0.9 million hectares of wheat and 0.5 million hectares of canola under the current EU biofuel policy and at 0.4 million hectares if this policy is removed. According to moisture and fibre analyses carried out in our study, the most suitable candidate for wood-based composites production is soft wood. [ABSTRACT FROM AUTHOR]

This paper focuses on the analysis of current cooperation trends in environmental protection research. A unified system of interrelations between research methods in the field of implementation of the bibliometric approach to the review of international cooperation in the field of environmental protection taking into account the consequences of the COVID-2019 pandemic was formed. To form a unified visualization of the analyzed bibliometric data, a special software product VOSViewer was used. Five clusters were defined: green—international cooperation for assessing risks to public health, in particular in the field of biosafety and the spread of social infections, with a focus on COVID-19, in 2019 and 2020; yellow—describes the related interaction between other clusters in the field of national and international mechanisms of cooperation in the regulation of greenhouse gas emissions and climate change; blue—brings together research areas in the field of economics of environmental management and control. The situation concerning the impact of the COVID-2019 pandemic is ambiguous, and it is crucial to recognize that this is a long-term period of impact, not only directly on public health but also due to economic and social constraints, as quarantine activities cause a chain of socio-economic crises. The problems of the environmental and economic spread of COVID-19 on various human activities and the environment require the development of this topic and the formation of a new cluster of interactions due to the wave dynamics of disease in the future. Broad cooperation and collaboration is proposed to address the challenges and accelerate sustainable development in Europe. A diagram of the main cooperation programs has been created, illustrating the overlap of the entire field, from basic research to the market. Further analytical studies will examine the effectiveness of cross-analysis using various scientometric databases to form an integrated approach to the new realities of quarantine activities. [ABSTRACT FROM AUTHOR]

In this study, 15 selected bottled mineral waters from chosen European countries were tested for their mineral nutrient contents. In particular, six important nutrients (Ca2+, Mg2+, Na+, K+, HCO 3 − , Cl−) were measured using atomic absorption spectroscopy. The content of mineral nutrients in all sampled mineral waters were compared to their expected content based on the label. Consequently, their taste was evaluated by 60 trained panelists who participated in the sensory analysis. The results from both the atomic absorption spectroscopy and sensory analysis were analyzed using the regression framework. On the basis of the results from the regression analysis, we determined to what extent the individual mineral nutrients determined the taste of the mineral water. According to the regression results, four out of six analyzed nutrients had a measurable impact on taste. These findings can help producers to provide ideal, health-improving nutrients for mineral water buyers. [ABSTRACT FROM AUTHOR]

The study deals with the possibility of waste utilization by using briquetting technology (production of solid fuels) and the potential of the manual low-pressure briquetting press in rural and peri-urban areas of East Java, where firewood is still commonly used as a source of energy for heating and cooking (besides LPG). The research compares households from the Donowarih village (Malang regency) and from the Maron peri-urban area (Blitar regency). Through quantitative and qualitative research, we document the potential of briquette production from household waste and agriculture production. The population from the peri-urban area is interested and willing to invest more in the technology, even though a higher biomass production has been found in the rural area. Financial possibilities were similar in both areas (p = 0.8986). A positive correlation (R = 0.5146) was found between the level of education and level of potential investments. Thus, higher education level meant higher interest in technology and the willingness to invest in it. In both areas there is a potential for briquette production and demand for its usage. Nevertheless, further research is recommended to find the suitable composition of bio-briquettes after the installation of wooden manual low-pressure briquetting press. [ABSTRACT FROM AUTHOR]

The present study investigates the quality changes of wood bio-briquette fuel after the addition of spent coffee ground (SCG) into the initial feedstock materials (sawdust, shavings) in different mass ratios (1:1, 1:3). Analysis of SCGs fuel parameter proved great potential for energy generation by a process of direct combustion. Namely, level of calorific value (GCV = 21.58 MJ∙kg−1), of ash content (Ac = 1.49%) and elementary composition (C = 55.49%, H = 7.07%, N = 2.38%, O = 33.41%) supports such statement. A comparison with results of initial feedstock materials exhibited better results of SCG in case of its calorific value and elementary composition. Bulk density ρ (kg·m−3) and mechanical durability DU (%) of bio-briquette samples from initial feedstock materials were following for sawdust: ρ = 1026.39 kg·m−3, DU = 98.44% and shavings: ρ = 1036.53 kg·m−3, DU = 96.70%. The level of such mechanical quality indicators changed after the addition of SCG. Specifically, SCG+sawdust mixtures achieved ρ = 1077.49 kg·m−3 and DU = 90.09%, while SCG + shavings mixtures achieved ρ = 899.44 kg·m−3 and DU = 46.50%. The addition of SCG increased wood bio-briquettes energy potential but decreased its mechanical quality. Consequently, the addition of SCG in wood bio-briquette has advantages, but its mass ratio plays an important key role. [ABSTRACT FROM AUTHOR]

In Central Vietnam, two key actors are involved in the extension performance of biogas technology: The owners of biogas plants and facilitators. Facilitators as the immediate providers of advice and services are in direct contact with local farmers and belong to the Vietnamese national extension network. This paper aims at identifying the current state of extension services and creating proper recommendations for further processes of training in the target area through the identification of context-specific knowledge (CSK). CSK can serve as a tool for facilitators and their quality involvement and for the improvement of current training practices in the area. It also provides performance indicators (PIs) for facilitators' quality assessments. PIs should be consistent parts of the educational process for the evaluation of knowledge transmission success. More research in terms of facilitator's impacts on the knowledge transition process towards the biogas owners should be done to prove the sustainability of the extension services. [ABSTRACT FROM AUTHOR]

The present study deals with the issue of bio-briquette fuel produced from specific agriculture residues, namely bamboo fiber (BF) and sugarcane skin (SCS). Both materials originated from Thừa Thiên Huế province in central Vietnam and were subjected to analysis of their suitability for such a purpose. A densification process using a high-pressure briquetting press proved its practicability for producing bio-briquette fuel. Analysis of fuel parameters exhibited a satisfactory level of all measured quality indicators: ash content Ac (BF—1.16%, SCS—8.62%) and net calorific value NCV (BF—16.92 MJ∙kg−1, SCS—17.23 MJ∙kg−1). Equally, mechanical quality indicators also proved satisfactory; bio-briquette samples' mechanical durability DU occurred at an extremely high level (BF—97.80%, SCS—97.70%), as did their bulk density ρ (BF—986.37 kg·m−3, SCS—1067.08 kg·m−3). Overall evaluation of all observed results and factors influencing the investigated issue proved that both waste biomass materials, bamboo fiber and sugarcane skin, represent suitable feedstock materials for bio-briquette fuel production, and produced bio-briquette samples can be used as high-quality fuels. [ABSTRACT FROM AUTHOR]

Production of bioenergy by the fermentation reaction is gaining attraction due to its easy operation and the wide feedstock selection. Anaerobic fermentation of organic waste materials is generally considered a cost-effective and proven technology, allowing simultaneous waste management and energy production. Small-scale biogas plants are widely and increasingly used to transform waste into gas through anaerobic fermentation of organic materials in the developing world. In this research, the quality of biogas produced in small-scale biogas plants was evaluated, as it has a direct effect on its use (as fuel for biogas cookers), as well as being able to influence a decision making process over purchasing such technology. Biogas composition was measured with a multifunctional portable gas analyser at 107 small-scale biogas plants. Complementary data at household level were collected via the questionnaire survey with the owners of biogas plants (n = 107). The average daily biogas production equals 0.499 m3, not covering the demand of rural households which are using other sources of energy as well. Related to the biogas composition, the mean content of methane (CH4) was 65.44% and carbon dioxide (CO2) was 29.31% in the case of biogas plants younger than five years; and CH4 was 64.57% and CO2 was 29.93% for biogas plants older than five years. Focusing on the age of small-scale biogas plants there are no, or only minor, differences among tested values. In conclusion, the small-scale biogas plants are sustaining a stable level of biogas quality during their life-span. [ABSTRACT FROM AUTHOR]