Content Of Organic Substances Research Articles

Microorganisms of solid waste as an opportunity for waste disposal and increasing environmental sustainability in the south of Kazakhstan

The study is devoted to the problem of processing the organic waste that is generated as a result of paper, textiles and other industries production as well as food waste. The growth of economic activity in Kazakhstan has resulted in a significant challenge with regard to industrial waste management. The accumulation of waste on the territory of the country has reached 31.72 billion tonnes, comprising approximately 2.5 billion tonnes of hazardous waste, 50 million tonnes of phosphorus-containing waste, over 2.5 million tonnes of lead-zinc waste and more than 120 million tonnes of solid domestic waste. The study object was the Shymkent-Kokys polygons. According to the research carried out, it was determined that the titer of microorganisms of the studied groups is 1–10 CFU/g in the soils selected around the garbage in the area of the Shymkent landfill. The titer of microorganisms in the soil horizons was high at a depth of 20–30 cm and the titer were 109 cells/mL. The structure of the soil microbiome obtained around the Shymkent Waste Landfill consists of actinomycetes, micromycetes, heterotrophic bacteria, nitrifying, nitrogen-fixing bacteria, enterobacteria, as well as algae and protozoa. It was found that strains KPA1, KPA2 Pseudomonas sp. strains KPA3, KPA4, KPA5 Bacillus sp. isolated from the soils of the Shymkent-Kokys landfill are able to recycle domestic waste with a high content of cellulose and organic substances up to 95%–97%. The findings can be used to develop more effective organic cellulosic waste management strategies and improve the environmental sustainability of various industries.

Determination and Optimization of Aerobic and Anaerobic Decomposition of Paper Sludge

The processing of paper sludge is currently an important environmental topic due to its high global production. The aim of this study is to monitor the biodegradation of paper sludge when the initial conditions change. Biodegradability tests 301F and OECD 311 were used to determine biodegradation. The data obtained from the tests were subsequently obtained for the simulation in MATLAB R2023b. The highest aerobic decomposition was approximately 80% after 28 days at an initial concentration of paper sludge leachate of 76 g/L. By simulating 3D modelling, we can predict that with a retention time of 1 day with degradation under aerobic conditions at the level of 70%, the ideal initial concentration of organic substances will be 157.55 g/L. Based on this model, it is possible to estimate that with a biogas production of 554 m3/tVS and a decomposition time of 20 days, it is necessary to set a concentration of approximately 128 g/L. Based on biodegradability tests, paper sludge was evaluated as suitable for aerobic or anaerobic biological decomposition.

Features of the microbiome of burial soils

Introduction. On the territory of the Russian Federation, as well as worldwide, a large amount of space is allocated for burials. The soils found in the burial areas have their own characteristics. In the scientific literature there is a few works devoted to the problem of hygienic assessment of cemeteries from the point of view of their impact on the environment, as well as on the population living next to necrosols or working on them. Depending on the chemical and biological effects, the microbial composition of the soil changes. This process is influenced by many factors, including humidity, the initial content of organic and mineral substances, level of acidity, structure of the soil and peculiarities of the course of intra-soil gas-phase reactions. The key participants in the decomposition of organic material are bacteria and fungi, the diversity and dynamics of which directly depend on the degree of soil contamination with pollutants. The purpose of this study was to analyze the microbiota of cemetery soil in its various layers. Materials and methods. The cemeteries of Moscow (NikoloKhovanskoye, Nikolo-Arkhangelskoye, Perepechenskoye), Moscow (Mytishchenskoye, Domodedovo), Tula (Municipal Cemetery No. 1 of the Municipal State Enterprise of the Municipal Formation of the City of Tula Combine of Specialized Services), Kursk (old city cemetery Kurchatov), Krasnoyarsk (Zheleznogorsk) regions and Altai (Yarovoye) Krais were selected as research objects for assessing the microbiome of soils. Results. The most common bacterial pathogens were found to be Enterococcus spp. (81%), Bacillus spp. (75%) and E. coli (45.1%). Mushrooms of Penicillium spp.. were isolated from 61% of the samples. The revealed microbiota profiles of the samples of the studied cemetery soils reflect the microbial composition of humans, which allows substantiating the main methods and algorithm for identifying decomposition processes depending on the time frame of burials. Limitations. The limitation of the study is due to the risk of contact with cemetery soil was not assessed, since not all genera of isolated microorganisms could be identified by their biochemical properties. Conclusion. Studies conducted in cemetery areas have shown how diverse the soil microbiome is in burial sites and varies depending on the depth of sampling. The microbiota profiles of cemetery soil samples identified during the study reflect the lifetime microbial composition of the human body, which makes it possible to substantiate approaches to identifying decomposition processes depending on the time frame of burials.

매립지 침출수 처리에서 질산화 공정 최적화 : pH 및 무기탄소원농도가 질소 제거에 미치는 영향

This study was conducted to solve problems that arise in the nitrification of landfill leachate due to the increase in waste generation and diversification of components associated with domestic economic growth. Landfill leachate contains high concentrations of nitrogen compounds and organic substances thus, it is a potential cause of environmental pollution. The study findings confirmed that the nitrification process was inhibited when the metal (Cu) concentration was more than 2.5ppm: further, the nitrification rate could be greatly improved by replenishing alkalinity and adjusting pH. Additionally, appropriate Do and pH alone did not have a sufficient effect on nitrification. This study is expected to contribute to the development of new treatment technology that can minimize the use of chemicals and suppress the generation of secondary toxic substances in the landfill leachate treatment process.

Technology of preparation and determination of the properties of kvas from table beet for use in bakery

In connection with the deterioration of the health of the population of Ukraine, the primary task should be to enrich the usual diet with products of functional purpose and to add natural biologically active additives that contribute to the removal of radionuclides, toxins, normalization of the body's systems and increased immunity. This work is devoted to the study of the process of beet processing and its further use in the bakery and confectionery industries. The refractometric method was used to determine the content of soluble solids. The content of trace elements was determined using the atomic adsorption method. When preparing kvass from table beets, additional raw materials were added: sprouted flax seeds, whey, yeast, viburnum powder, rye bread crackers. It was established that the variety of the Dutch selection Roket differs from the varieties Bordeaux 237 and Cylindra in terms of dry matter, organic acids, dyes and sugars. It is important to note that when improving kvass preparation technology, optimal fermentation conditions and dosing of additives are taken into account in order to maximize the shelf life of the product without losing its quality. In view of the increase in the number of genetic and complicated diseases, it is worth noting the introduction of specialized dietary programs, which are gaining more and more relevance. Such programs have been found to ensure food security and meet all essential nutrient needs. Considered the problem of the need for constant improvement of recipes of food products, study of new gluten-free alternatives and provision of access to high-quality gluten-free products. Studies have proven that the use of natural raw materials in the production of beet kvass is an effective means of improving its quality characteristics. Therefore, a promising direction in the production of flour products is the improvement of the recipe of the existing assortment due to the use of natural plant components of increased biological value. Kvass from table beet can be a source of natural biologically active substances (BAR). Table beets have a rich chemical composition. The nutritional value of beets is additionally balanced by the content of sugars and acids (citric and oxalic), the content of organic substances, minerals and vitamins. The production of bakery products using kvass from table beet as a natural food additive is relevant today.

Application of coal-based solid waste artificial soil in the restoration of saline alkali land-taking the saline alkali land restoration of the Emao River in China as an example

In this paper, coal-based solid waste, including fly ash, desulfurization gypsum, furnace bottom slag, and coal washing sludge in the ratio of 3:2:3:2 with a total of 200 tons/0.07 hm2, were used as the specialized main material for restoring the saline alkali land of Emao River in Huairen of China. The remediation effect and safety of solid waste artificial soil were evaluated by testing the soil samples before and after the remediation. The results showed that the pH value of the soil after remediation decreased from 9.98 to 7.60, which was close to the neutral value and suitable for crop growth. The total amount of water-soluble salts decreased from 8.30 g kg−1 to 4.80 g kg−1 with a decrease of 42.2 %. The organic matter increased from 6.5 g kg−1 to 39.1 g kg−1 with a 5-fold increase. Compared to the original soil, the heavy metal content in the restored soil did not increased, but instead decreased, indicating that the restoration technology was feasible and meets environmental requirements. Corn planting experiment results showed that corn's emergence rate in the original saline alkali soil was extremely low (about 1 %), while in the restored soil reached over 99 %. The average yield of corn in restoration field was 16.56 % higher than the average local yield level. The residual content of heavy metals and organic toxic substances in corn and potatoes grown on restored soil were analyzed, and the results showed that the detected heavy metal content was far lower than the standard values, and the residual organic toxic substances were basically not detected, indicating that the agricultural fruits grown on restored soil were safe, harmless, and edible. This approach could achieve large-scale consumption of coal-based solid waste, increase arable land, and reduce the cost of restoring saline alkali land.

Oral Klebsiella sp. Involved in Dental Caries: A Case of Individuals Gargling with Peatwater

Most of the microbes inhabiting the oral cavities are harmless but can cause disturbance and discomfort if the microbial population increases significantly. One of the oral disorders that is often experienced by children, is dental caries. Dental caries is causedby various factors, including eating and brushing habits. The people of Central Kalimantan who live in the watershed use peat water in their daily activities, including for gargling and brushing their teeth. The acidic characteristics of peat water and the high content of organic substances trigger the development of microbes that cause dental caries.This study used dental caries swab samples of patients who rinsed their mouths with peat water. Bacteria were identified molecularly with 16SrRNA markers with primers 63F and 1387R. The similarity of nucleotide sequences was analyzed with BLAST on GeneBank. A phylogenetic tree was built with Maximum Likelihood. Both isolates have a fairly high level of similarity to Klebsiella pneumoniae, namely 91% and 93%. Both isolates are in the same clade, Klebsiella spp., and are close to various commonly found bacteria in the oral cavity, such as Streptococcus mutans and Lactobacillus salivarius.

Differences in the constituents of bacterial microbiota of soils collected from two fields of diverse potato blackleg and soft rot diseases incidences, a case study

The presence of bacteria from the Dickeya spp. and Pectobacterium spp. in farmlands leads to global crop losses of over $420 million annually. Since 1982, the scientists have started to suspect that the development of disease symptoms in crops might be inhibited by bacteria present in the soil. Here, we characterized in terms of physicochemical properties and the composition of bacterial soil microbiota two fields differing, on the basis of long-term studies, in the occurrence of Dickeya spp.- and Pectobacterium spp.-triggered infections. Majority, i.e. 17 of the investigated physicochemical features of the soils collected from two fields of either low or high potato blackleg and soft rot diseases incidences turned out to be similar, in contrast to the observed 4 deviations in relation to Mg, Mn, organic C and organic substance contents. By performing microbial cultures and molecular diagnostics-based identification, 20 Pectobacterium spp. strains were acquired from the field showing high blackleg and soft rot incidences. In addition, 16S rRNA gene amplicon sequencing followed by bioinformatic analysis revealed differences at various taxonomic levels in the soil bacterial microbiota of the studied fields. We observed that bacteria from the genera Bacillus, Rumeliibacillus, Acidobacterium and Gaiella turned out to be more abundant in the soil samples originating from the field of low comparing to high frequency of pectinolytic bacterial infections. In the herein presented case study, it is shown for the first time that the composition of bacterial soil microbiota varies between two fields differing in the incidences of soft rot and blackleg infections.

Influence of acid and thermal treatment on regeneration of spent bleaching clay and conversion of residual oil to biodiesel

ABSTRACT Spent bleaching clay (SBC) is a hazardous waste produced by vegetable oil refining industries. SBC contains a residual oil (RO) with a lot of organic and inorganic impurities and its disposal leads to severe environmental consequences. In this study, SBC regeneration by extraction, acid modification and pyrolysis under various conditions and biodiesel production were studied. The GC-MS of the extracted RO shows that the fatty acid content is in conformity with crude oil and is appropriate for biodiesel production. FTIR was recorded in order to evaluate the main functional groups of fresh-, spent-, regenerated bleaching clay. The specific surface area (SSA) of fresh bleaching clay (FBC) (166.1 ± 1.7 m2/g) was lower than regenerated bleaching clay (RBC) one. The highest SSA (252.1 ± 1.7 m2/g) was revealed by pyrolysis at 550°C and activation with 10% sulfuric acid. Subsequent increase in the acid concentration and temperature of pyrolysis caused a decrease in the SSA. The heavy metals concentration in RBC was lower than the limits for activated bleaching clay in the National Food Safety Standard. Hence, RBC effectively copes with heavy metal removal. The peroxide, anisidine, acid values and oxidation stability of oil bleached with RBC are comparable to the FBC. Implications: The disposal of spent bleaching clay from vegetable oil refining industries has been recognized as a significant environmental issue. After adsorbing the impurities, spent bleaching clay becomes contaminated with a high concentration of organic and inorganic substances, including residual oils, fatty acids, phospholipids, and potentially toxic heavy metals. This makes spent bleaching clay a hazardous waste and improper disposal can lead to severe environmental consequences. Due to the potential environmental harm caused by spent bleaching clay disposal, it is crucial for vegetable oil refining industries to adopt proper waste management practices. Overall, the proper management and disposal of spent bleaching clay is essential to prevent environmental contamination and safeguard human health.

Synergetic sludge conditioning by US enhanced Fe2+ activated sodium persulfate: Physicochemical properties and mechanisms

Efficient dewatering of sewage sludge is an energy- and carbon-saving procedure for sludge treatment in wastewater treatment facilities. The ultrasound-coupled divalent iron ion activated persulfate process can effectively promote sludge dewatering and improve organic substance content. Under the action of ultrasound (US 50 w/L), divalent iron ions (Fe2+) 200 mg/g (TS), and persulfate (PDS) 200 mg/g (TS) for 60 min, the capillary suction time (CST) was reduced by 79.74%, and the moisture content of the dewatered sludge cake reached 56.51 wt%. The organic carbon content of treated sludge was also four times higher than the original sludge and types were richer in short-chain volatile species in US/Fe2+/PDS. Moreover, the correlation analysis found that the relationship of between CST and SV30, Zeta and lactate dehydrogenase (LDH) were positive correlation, and the relationship of SCOD and TC were positively correlated with the PN (SB-EPS). Mechanistic studies showed that the US/Fe2+/PDS system could produce oxygen activators by US coupling Fe2+ to strengthen the effect of activated PDS strongly, while the sulfate radicals (SO4·-) radical was a dominant role. The cracking mechanism is divided into two pathways effectively degraded the macromolecule EPS into a small-molecule acid and further reduced the water-holding interfacial affinity as follow: (1) the radical path dominated by hydroxyl radicals (·OH), SO4·-, and superoxide radical (O2·-); (2) the non-radicals dominated by monoclinic oxygen (1O2). Afterwards, the electrostatic force and interfacial free energy were reduced, resulting in enhanced self-flocculation and mobility to enhanced dewaterability. These findings demonstrated the US/Fe2+/PDS system had significant advantages in sludge cracking and provided theoretical support for its practical application.

IMPROVEMENT OF ELEMENTARY COMPONENT OF DAMAGED SUBSTRATES BY SAPONITE CLAY INCLUSION

In this proposed article, the impact on the elemental composition of sand substrates is determined using the example of the Andriykovetskyi quarry-dump complex and the Barsukivskyi sand pit, which are located in the Central Podillya region in the conditions of the Right-Bank Forest-Steppe. It was determined, that saponite clay contains a significant amount of macro- and micro- elements, and the directions of this use depend on the composition and origin of saponite: in agriculture, in industry, in construction, an application as a sorbent or as meliorant, etc. It is noted that the use of saponite as an ameliorant is an economical and cost-effective method of reclamation, which allows to reduce the burden on the environment caused by the extraction of minerals, pollution of the territory by heavy metals, the conduct of hostilities, etc. General scientific (analysis), statistical (statistical analysis) and laboratory methods (Fourier-transform spectroscopy) were used to assess the qualitative composition of inorganic and organic components of sand-saponite mixtures and to determine saponite clay as a potentially fertile material. To conduct the research, an averaged sample of sand was taken from the Andriykovetskyi quarry and dump complex and from the Barsukivskyi sand pit. For comparison with reference values, a zonal soil sample was taken from undisturbed areas. Saponite from the Tashkiv deposit with a fraction of 0.1 mm was used for sand-saponite mixtures, the ratio of sand substrate to saponite is 70% to 30%. According to the results of the study of the qualitative composition of the inorganic component, it was determined, that saponite has a positive effect on the composition of the sand-saponite mixture in terms of providing plants with nutrients, such as macro- and micro- elements (Mg, K, Na, Cu, Zn, Ca). This confirms the positive effect of saponite on plant growth, which was obtained by us in previous biotesting experiments, and is explained by the fact that the elements of the sand-saponite substrate are available to plants as a result of their transition into the substrate solution. Adding saponite to the substrate of sand pits also increases the content of organic substances, which accelerates the processes of humification and the formation of soil aggregates: humic acid contributes to the bonding of soil particles; carbohydrates sucrose, fructose, glucose and lactose create a nutrient environment for plants; stearates and stearic acid are the main soap components, lauric acid is a foaming catalyst, their presence in sand-saponite mixtures indicates their transition from saponite. When comparing the samples of sand-saponite mixtures of the Andriykovetskyi quarry-dump complex and the Barsukivskyi sand pit, it was concluded that the processes of soil formation began in the substrate of the Andriykovetskyi quarry-dump complex, since the composition of organic matter is greater here.

Preliminary tests on carbon and nitrogen emissions and nutrients availability upon application of algal-bacterial granules to arid and low fertility soil

To remediate arid and low fertility soil and explore the feasibility of controlling its carbon (C) and nitrogen (N) emissions, algal-bacterial aerobic granular sludge (AGS) was applied as soil additives and compared with bacterial AGS and cyanobacteria during 14 days’ incubation. Results show that algal-bacterial AGS as additives possesses a higher potential in terms of fertility recovery and soil physicochemical properties conservation. The additives may change the soil characteristics by decreasing soil pH (within 0.6) and water content (0.8–2.5 %) with increased electrical conductivity during the 14 days’ incubation. As for soil fertility, due to the high available phosphorus (P) content in algal-bacterial AGS, the soil available P content was significantly increased from 50 % to 170 % after incubation under different application rates or gaseous environments. N was also accumulated in the soil matrix with increased inorganic forms and less or acceptable N emission. The contents of soluble organic substances and extracellular polymeric substances (EPS) were significantly increased after incubation. Under ambient air and moderately elevated CO2 like 10 % conditions, carbon mineralization in the soil samples was lower than 15 % at low additives dosages; while under an elevated CO2 content (25 %) condition, a higher additives dosage may cause a rapid CO2 accumulation within 2 days with a substantial O2 consumption, leading to an anaerobic/anoxic environment corresponding to a higher C mineralization and/or N loss.

Planar non-contact microwave sensor for the detection of aqueous organic and inorganic samples

In this study, a planar microwave sensor was proposed and manufactured with the aim of detecting and categorizing concentrations of various organic substances, including methanol (CH3OH), ethanol (CH3CH2OH), and 1-butanol (CH3CH2CH2CH2OH), as well as inorganic substances such as sodium carbonate (Na2CO3), potassium carbonate (K2CO3), and sodium hydroxide (NaOH). Throughout the sensor's development, a configuration incorporating a microstrip line and a rectangular patch with a central circular aperture was employed. Full-wave electromagnetic simulation software was utilized to analyze the performance of the sensor in terms of reflection coefficients. The sensor was fabricated using a PCB material with defined properties, which included a dielectric constant of 4.3, a loss tangent of 0.025, and a thickness of 1.6 mm. The reflection coefficient (S11) was measured and analyzed using principal component analysis (PCA) to identify correlations between the classification groups and concentrations of organic and inorganic samples. Additionally, the equivalent circuit has been extracted and modeled to describe the operating mechanism of the microwave sensor. The simulation and measurement results indicate that the sensor is a suitable candidate for the detection and classification of water samples containing CH3OH, CH3CH2OH, CH3CH2CH2CH2OH, Na2CO3, K2CO3, and NaOH. The proposed microwave sensor features a surface area of 29 × 18 mm², leading to a noteworthy reduction in surface utilization compared to other breath biosensors designed for measurement purposes.

Thermal Analysis of Combustible Components of Municipal Solid Waste

The use of municipal solid waste as a raw material for alternative fuel is a promising direction for waste recycling and substitution of solid fossil fuels. Therefore, selecting of fuel composition and studying of its properties is an urgent task. The aim of this work is thermal characteristics analysis of the combustible components of municipal solid waste, which are the most common in Ukraine, for further selection of a fuel composition that will satisfy the consumer's requirements. The goal is achieved by studying the thermal destruction of samples by thermogravimetry and differential thermal analysis when materials are heated to 1000 ºС in the presence of air oxygen. Paper, cardboard, plastic, biodegradable film, textiles, leather, wood were investigated in this work. The most important results are the received data on the characteristic temperatures of destruction stages, content of water, organic and mineral substances, ash, as well as the calculated values of rate and conditional thermal effect of decomposition of organic substances. Strong formation of gaseous substances was registered for samples of polyethylene and biodegradable film, polyethylene terephthalate and cotton fabric. These features should be considered in the technologies of production and combustion of fuel. The significance of the results also lies in the fact that it is recommended to use data on the thermal stability of materials in order to prevent their ignition during drying when developing fuel production technology. In addition, the calculated values of the conditional thermal effect made it possible to evaluate the thermal characteristics of the studied materials as components of solid alternative fuels.

О зависимости процесса промерзания грунтов от влажности

Purpose: the temperatures at which soils begin to freeze during the onset of frost are of interest primarily to agricultural workers and construction workers. It was previously established that many factors influence soil freezing. However, not enough research has been carried out on the influence of individual factors on the freezing process. The article examines the influence of soil moisture on their supercooling and freezing temperatures. Methods: the studies were carried out in a microrefrigerator with three freezing modes. Results: it was found that with constant shaking, the supercooling temperature increased, but the freezing temperature did not change. Graphic dependences of the temperatures of supercooling and freezing of soils on the initial humidity were obtained. The degree of soil compaction did not affect these temperatures. The temperatures of supercooling and freezing of soils depend to a greater extent on the dispersion of soils than on the content of organic substances in them. Practical significance: the results of the work are important for construction as they expand the understanding of the features of the mechanism of soil freezing.

European Green Deal: Justification of the Relationships between the Functional Indicators of Bioenergy Production Systems Using Organic Residential Waste Based on the Analysis of the State of Theory and Practice

Based on the analysis conducted on the state of theory and practice, the expediency of assessing the relationships between the functional indicators of bioenergy production systems using the organic waste of residential areas is substantiated in the projects of the European Green Deal. It is based on the use of existing results published in scientific works, as well as on the use of methods of system analysis and mathematical modeling. The proposed approach avoids limitations associated with the one-sidedness of sources or subjectivity of data and also ensures complete consideration of various factors affecting the functional indicators of the bioenergy production system from the organic waste of residential areas. Four types of organic waste generated within the territory of residential areas are considered. In our work, we used passive experimental methods to collect data on the functional characteristics of bioenergy production systems, mathematical statistics methods to process and interpret trends in the functional characteristics of bioenergy production systems using municipal organic waste, and mathematical modeling methods to develop mathematical models that reflect the patterns of change in the functional characteristics of bioenergy production systems. The results indicate the presence of dependencies with close correlations. The resulting dependencies can be used to optimize processes and increase the efficiency of bioenergy production. It was found that: (1) yard waste has the highest volume of the total volume of solid organic substances but has a low yield of biogas and low share of methane production; (2) food waste has the highest yield of biogas and, accordingly, the highest share of methane production; (3) mixed organic waste has the lowest volume of the total volume of solid organic substances and the lowest content of volatile organic substances. The amount of electricity and thermal energy production varies by type of organic waste, with mixed organic waste having a higher average amount of electricity production compared to other types of waste. It was established that the production volume of the solid fraction (biofertilizer) is also different for different types of organic waste. Less solid fraction is produced from food waste than from yard waste. The obtained research results are of practical importance for the development of sustainable bioenergy production from organic waste in residential areas during the implementation of the European Green Deal projects. They provide further research on the development of effective models for determining the rational configuration of bioenergy production systems using organic waste for given characteristics of residential areas.

Toxicity stress alleviation through cometabolism and lignite activated coke immobilization in bioelectrochemical systems

Bioelectrochemical systems (BESs) are a technology that can biodegrade contaminants and generate electricity, yet their performance is largely constrained for industrial wastewater treatment due to toxic pollutants. The present study aimed to investigate the combined effects of cometabolism and lignite activated coke (LAC) immobilization (N-L-MFC) on alleviating the inhibitory impacts of coking wastewater and enhancing biodegradation. Improved degradation performance was achieved, showing that the removal of chemical oxygen demand (COD), total organic carbon (TOC) and ammonia nitrogen (NH4+-N) within 12 h was 91.7 %, 88.1 % and 72.1 %, respectively. Data analysis with the Haldane inhibition model revealed that N-L-MFC had good tolerance to high pollutants, and the inhibition concentration of organic and inorganic substances was 2.1 ∼ 6.4 times higher than that of cometabolism (N-MFC) or LAC packing (L-MFC). Separately, the cometabolism process minimized poisoning towards microorganisms by enhanced aromatic matter and inorganic biodegradation. LAC alleviated the toxicity of macromolecular and unsaturated groups by adsorption. The electrical properties indicate the resistance for electron transfer significantly relieved in N-L-MFC. From microbial community analysis, nontolerated electroactive bacteria Geobacter enriched in N-L-MFC indicate the positive succession of functional bacterial. Immobilized facultative bacteria such as Pseudomonas, Proteiniphilum, and Corynebacterium enriched on LAC involve in multiple metabolism process which also exerted synergistic degradation for aromatic organics, inorganics, and NH4+-N metabolism in biochemical processes. This research provides an efficient strategy for treating wastewater with recalcitrant contaminants by bioelectrochemical process.

Bacterial diversity in cheese wastewater using Next-Generation Sequencing (NGS)

Abstract. Estikomah SA, Suranto, Susilowati A, Masykuri M. 2024. Bacterial diversity in cheese wastewater using Next-Generation Sequencing (NGS). Biodiversitas 25: 482-490. Cheese wastewater (whey) has a high content of organic substances, including lactose, protein, and fat. The lactose in whey wastewater can also be used as a bacterial growth medium. Bacterial community structure is an essential aspect of microbial water quality. The bacterial diversity data obtained can then be used to evaluate the existence of bacteria that might be useful for making microbiological products. This research employs Next Generation Sequencing (NGS) technology to determine the diversity and abundance of bacteria based on 16S rRNA gene amplicons for further processing of whey wastewater. The NGS-based technique overcomes the limitations of conventional bacterial culture techniques. The effectiveness and accuracy of microbial diversity analysis employing NGS technology are high. The research method includes the steps of sample preparation, DNA extraction using a ZymoBIOMICS DNA Microprep Kit (D4300), PCR amplification of the V3-V4 16S rRNA gene region, DNA sequencing, and a bioinformatics-statistical analysis. The results show that bacterial diversity in whey wastewater was found to have an average number of Operational Taxon Units (OTUs) of 259 tags. The metagenomics study of the microbial community in whey wastewater successfully detected the dominant genus of bacteria, which can benefit the management of whey wastewater. The presence of Lactobacillus and Acetobacter confirms that cheese whey wastewater exists in Yogyakarta Province. Acetobacter can oxidize ethanol to produce acetic acid, a pungent odor characteristic that causes environmental pollution. On the other hand, the presence of Lactobacillus and Acetobacter shows that whey wastewater can be reprocessed to produce fermented beverages, thereby improving their value and minimizing the impact of environmental pollution.

Removing refractory organic substances from landfill leachate using a nanofiltration membrane bioreactor: Performance and mechanisms

Membrane bioreactors (MBRs) are typically used to dispose landfill leachate, but they are challenged by the low removal of refractory organic substances. To address this challenge, in this study, we replaced the commonly used microfiltration (MF) membranes in conventional MBRs with nanofiltration (NF) membranes, i.e., MBRNF. We operated a one-step MBRNF for 127 days and benchmarked against a conventional MBRMF in terms of membrane fouling, pollutants removal, and bulk solution properties. The results showed that the NF membrane could effectively reject refractory organic substances, leading to a longer organic retention time (ORT) and a higher concentration of refractory organic substances in the bioreactor. Consequently, the MBRNF outperformed MBRMF by 20 %–30 % in removing of refractory organic substances, mainly by the enhanced biodegradation of refractory organic substances with low molecular weight. Further investigation suggested that the enhanced biodegradation in the MBRNF could be ascribed to 1) more biomass in the bioreactor; 2) higher concentration of refractory organic substances in the bioreactor; and 3) the enrichment of dominant bacteria such as Chloroflexi. These findings highlight the potential of MBRNF in removing refractory organic substances from landfill leachate and other wastewaters with poor biodegradability.

Сurrent state and prospects of the Sakhalin balneological potential in rehabilitation and health resort treatment

Aim. To assess the prospects for the use of mineral waters and therapeutic muds (peloids) of the Sakhalin region for treatment and prophylactic purposes on the basis of their balneological properties.Materials and methods. The results of balneological analyses of mineral waters and therapeutic muds of the island areas of the Sakhalin region and regulatory documents were used.Results. The mineral waters and therapeutic muds of the Sakhalin region as its major therapeutic resources are characterized. The main groups of mineral waters for internal and external use include siliceous thermal, iodobromic, arsenic, and boric waters. It is noted that unique deposits of Sakhalin-type mineral waters, such as acidic waters with a high content of metals, petroleum products, and organic substances, require additional research. The Sakhalin region is rich in all available types of therapeutic muds– silt sulfide, mound, peat, and sapropel.Conclusion. The Sakhalin region possesses a wide variety of balneological resources for health resort treatment and rehabilitation. Among them are the deposits of mineral waters and therapeutic muds that are promising for research and use in medical and wellness organizations.