Dissolved Oxygen Levels Research Articles

ВЛИЯНИЕ УРОВНЯ РАСТВОРЕННОГО КИСЛОРОДА НА СПОРООБРАЗОВАНИЕ B. SUBTILIS ПРИ ГЛУБИННОМ КУЛЬТИВИРОВАНИИ В БИОРЕАКТОРЕ

This paper presents research findings on the impact of dissolved oxygen levels on the spore formation of B. subtilis during submerged cultivation in a bioreactor. The experiments analyzed both static and dynamic oxygen levels. The study revealed that oxygenation changes significantly affect the kinetics and yield of B. subtilis spores. When static DO values ranged from 0% to 50%, the process proved economically inefficient, with either non-viable bacteria at the end of the cycle or a spore yield that was not cost-effective. Conversely, DO levels from 50% to 0% resulted in rapid spore formation, followed by a shift from sporulation form back to vegetative form. The research identified the optimal dissolved oxygen range for cultivation as a dynamic cycle between 0% and 50%, where sporulation occurred after 36 hours, with spores comprising 95% of the total bacterial mass. This study broadens our understanding of biotechnological growth factors in bioreactor systems. Microbiological and biotechnological methods were used for submerged cultivation in bioreactors, along with physicochemical monitoring of dissolved oxygen. The practical relevance of this study lies in its potential application in controlling the cultivation of this microorganism for industrial biotechnological processes.

Hybrid Power Source in Fish Farming With Help of IoT Technology

Fish farming is a difficult, task that involves growing fish without risk. Maintaining the pond's water quality allows for safe fish production. This will go over the creation of a real-time water quality system to monitor fish farms. The water quality monitoring system includes a dissolved oxygen sensor, a pH sensor, and a water temperature sensor. The Arduino Nano microcontroller is linked with the Internet of Things (IoT) platform to provide real-time remote water monitoring. The system is intended to efficiently monitor water quality in freshwater fish farms, specifically water parameters suitable for fish. Instead of testing the system in the real fish farm, it is tested using water that is simulated to the water quality for the fish farm. If the water was above and below the fixed parameter it gives us an alert and water exchange mechanism get started by remove the dirty water from the pond through the solenoid valve and provide the fresh water into the pond. By measuring the dissolved oxygen level if is any deviation occurs water circulation mechanism should be established and circulate the water for increasing the oxygen level by using the padding wheel which all these done automatically. It also done the automatic food feeding at the periodic interval time without the manual involvement sometimes it may cause a manual error such as underfeeding and overfeeding which may affect the fish health to reduce such stuffs we use this automatic food feeding system. Keywords: Fish farming; IoT; Solar energy; Solar PV.

Alterations in Immunology in Three Sizes of Black Jaw Tilapia (Sarotherodon melanotheron) Exposed to Dimethoate in the Laboratory

Three different sizes of Black Jaw Tilapia (Sarotherodon melanotheron) were subjected to dimethoate exposure in the laboratory, and changes in their immunology were observed. The fish were treated with the chemical for 15 days at five different concentrations: 0.00 (control), 0.05, 0.10, 0.15, and 0.20 mg/L. The trial involved the assessment of six water quality variables, including temperature, pH, salinity, dissolved oxygen, nitrite, and ammonia. After the experiment, blood samples from the fish were obtained, and standard laboratory procedures were used to look for immunological profiles in them. Based on all the parameters evaluated, the findings indicated that the chemical had a detrimental effect on the organism even at the lower concentration (0.05 mg/L) over the duration of time (15 days). The findings also showed that the values for ammonia and nitrite increased in proportion to the chemical’s concentration. At the same time, the dissolved oxygen levels dropped (P<0.05). While temperature, pH and salinity were all within the same range for every chemical concentration. However, the chemical significantly distorted the immunological profiles of S.melanotheron, with increasing leucocytosis. Following exposure to this chemical, there are substantial decreases (monocytopenia) and significant increases (P<0.05) in the number of each cell type as well as in the number of lymphocytes (lymphocytosis), eosinophils (eosinophilia), and neutrophils (neutropenia). The study showed that the chemical has a dose-dependent effect on the fish’s immune system. Therefore, care should be exercised when applying this chemical in close proximity to an aquatic environment.

Assessing Hydrological Dynamics during the Monsoon Season in the Hooghly River, West Bengal, India: An Evaluation of Comprehensive Pollution Index and Water Quality index

This study meticulously evaluates the water quality parameters of the Hooghly River during the period spanning 2022 to 2023, specifically during high tide, with a particular focus on the locales of Kamarhati, Panihati, and Khardah. A comprehensive analysis encompassed both physico-chemical and biological parameters. The application of Pollution indices, notably the Water Quality Index (WQI) and Comprehensive Pollution Index (CPI), elucidates the water quality status at the selected sampling locations. Elevated E. coli levels (Kamarhati: 10000, Panihati: 15000, Khardah: 20000), turbidity, and total suspended solids exceeded WHO and BIS standards, categorizing the river as slightly polluted (CPI: Kamarhati-0.67, Panihati-0.68, Khardah-0.59), rendering the water unsuitable for consumption (WQI > 100). Low dissolved oxygen levels (1.9-2.4 mg/l) and significant microbial contamination (coliform: 10000-20000 MPN) underline the urgent need for targeted interventions. While pH, temperature, and DO levels suggested a stable aquatic environment, elevated TDS, TSS, and E. coli concentrations signify potential pollution sources, necessitating immediate water treatment. Moderate levels of BOD and COD indicate a manageable organic pollutant load, and nitrate and nitrite within permissible limits are positive.

Evaluation of oxidative stress on Zebrafish under different pH and dissolved oxygen levels using MDA as biomarker

Oxidative stress on zebrafish (Danio rerio) has been evaluated for pH (four levels namely pH 4.5-5.5, 5.5-6.5, 7.5-8.5 and 8.5-9.5) and Dissolved Oxygen (DO 20-30%, 40-50% and 60-70%) in terms of oxygen saturation. Temporally, the exposure for pH levels were maintained from as 1h, 2h, 3h and 4h and for DO, it was (4h, 8h, 12h and 16h. The malondialdehyde (MDA) was used as biomarker of oxidative stress. It was observed that out of all tissues (skeletal muscle, liver, gill and brain) analyzed, zebrafish showed highest stress response in skeletal muscle against both environmental ambiances. In case of pH levels, significant increase in MDA level in skeletal muscle was recorded at pH 4.5-5.5, and the MDA level of skeletal muscle at 2h showed significant increase at this level of pH. Whereas, at DO 20-30% saturation level, skeletal muscle tissue significantly responded at this level of DO saturation and showed the maximum MDA level compared to the other tissues. On analysis for the duration of exposure, it was observed that skeletal muscle of zebrafish showed highest levels of MDA at DO 40-50% O2 saturation for 12h. In conclusion, it has become evident that zebrafish may undergo oxidative stress at pH 4.5-5.5 when exposed for 2hours, similarly, for DO it is 20-30% saturation for 12 hour exposure.

Artificial Intelligence for Water Quality

Abstract: This study delves into how AI can be applied within water and environmental engineering research, particu- larly emphasizing the utilization of machine learning models to advance the accuracy of water quality predictions in the Delaware River. Through an analysis of time series data spanning from 2020 to 2022 and the utilization of exploratory data analysis methods, this investigation scrutinizes various elements influenc- ing the dynamics of water quality. For water quality time series analysis, identifying changes in long-term trends is important, yet identifying specific change-points is also important[3]. A strong correlation is notably detected between levels of dissolved oxygen and recorded temperatures. Leveraging this correlation, an intricate polynomial regression model is crafted to forecast dissolved oxygen concentrations based on expected temperature values. This predictive model not only clarifies the inherent link between dissolved oxygen and temperature but also offers insights into projecting future dissolved oxygen levels in the Delaware River, considering anticipated temperature fluctuations. These findings hold significant promise, potentially enhancing ecologi- cal evaluations and the development of impactful management strategies, specifically designed for water quality monitoring and conservation efforts within the Delaware River basin. Hence, eval- uation of water quality of groundwater is extremely important to prepare for remedial measures[1].

Water Quality Assessment of The Three Lakes of Barandabhar Forest Corridor, Central Nepal

Addressing the global challenge of securing water for both human needs and ecosystem health is crucial. This study aims to characterize the physiochemical parameters of three lakes in the Bharandabhar forest corridor, Chitwan, Central Nepal: Tiger Lake, Kalimati Lake, and Rhino Lake. During the pre-monsoon season, four different sites (Eastern, Western, Northern, and Southern) of each lake were examined. To ensure precision, five replicated water samples were collected from each site, and standard protocols were applied to analyze various physiochemical parameters, such as pH, temperature, dissolved oxygen, free carbon dioxide, total hardness, chloride, total alkalinity, conductivity, nitrate, inorganic phosphorus, and total solid matter. Also, the Water Quality Index (WQI) was calculated. Results show that physiochemical parameter values mostly align with permissible limits according to regional and international guidelines. However, the mean phosphorous concentration and pH values of Tiger and Kalimati lakes exceed these limits. Rhino Lake displayed a mildly alkaline pH, while Kalimati and Tiger lakes exhibited slightly acidic characteristics. An interesting observation is the significant negative correlation between temperature and dissolved oxygen, indicating that as temperature rises, dissolved oxygen levels decrease. Additionally, WQI suggests that all three lakes maintain good water quality. However, a concerning finding is that all three lakes exhibited hyper-eutrophic conditions based on their phosphorous concentration. The lakes face significant threats due to high levels of organic pollutants and a rapid eutrophication process. Authorities must take significant actions to safeguard the lakes and ensure their future well-being. This research highlights the urgent need for environmental protection and conservation efforts to preserve the water quality and ecological balance of the Bharandabhar forest corridor lakes for the well-being of both human communities and the ecosystem.

Water quality and the presence of metals in crustaceans (Sartoriana spinigera) and mollusks (Pila globosa) close to an urban waste landfill in Kodda at Gazipur

Degradation of water and sediment quality along with other aquatic ecosystem components, due to urban waste is a significant concern that demands attention. Despite of the multifaceted use of the Konabari area within the Gazipur City Corporation of Bangladesh, limited studies have assessed the health of the floodplain ecosystem adjacent to urban waste landfills in Kodda. This research focuses on evaluating water quality parameters and the presence of metals and metalloids in water, sediment, and biota (invertebrates) in the lowland floodplain near the Kodda municipal landfill in Gazipur district. In December 2022, thirteen composite samples, including water, sediment, crustaceans (Sartoriana spinigera), and mollusks (Pila globosa), were collected from the designated sampling site. Surface and sub-surface (0–15 cm depth) water were collected using a water sampler for water quality analysis, and the presence of heavy metal and metalloid content of the water, sediment, crabs, and mollusks were analyzed using an atomic absorption spectrometer. The results indicated dissolved oxygen concentrations ranging from 0.30 to 5.81 mg/l (mean 3.1±2.37 mg/l). Certain locations directly affected by waste discharge exhibited alarmingly low dissolved oxygen levels (~0.71 mg/l), coupled with elevated temperatures and phosphate (PO43−) content (2–7.4 mg/l). The scarcity of heavy metal concentrations (<0.0677 mg/l) in water may be attributed to the constant flow of water preventing metal accumulation in the flowing water. However, sediment analysis revealed significantly higher concentrations (mean±Sd) of Fe (15240±1211 mg/kg), Mn (1122±180 mg/kg), Cu (44±5.5 mg/kg), Cr (28±3.2 mg/kg), Ni (39±2.4 mg/kg), As (3.7±0.89 mg/kg), and Zn (72±3.95 mg/kg) compared to other studies in various locations. Crustacean (Crab) samples showed concentrations of Cr, As, Pb, Cd, Zn, and Cu exceeding recommended permissible limits. Pila globosa emerged as an effective ecological bioindicator of aquatic pollution, with concentrations of Cr, Mn, Ni, Cu, Zn, and Pd exceeding recommended limits. Despite eco-environmental indices suggesting low to moderate contamination, the heavy metals and metalloids study indicated degradation of ecosystem health triggered by urban waste discharge. Consequently, the study recommends proper waste treatment in landfills and their transformation from open dumps to scientifically managed controlled waste landfills. Ann. Bangaldesh Agric. 27(2):175-189

Enhanced poly-γ-glutamic acid synthesis in Corynebacterium glutamicum by reconstituting PgsBCA complex and fermentation optimization

Previously, a novel Corynebacterium glutamicum strain for the de novo biosynthesis of tailored poly-γ-glutamic acid (γ-PGA) has been constructed by our group. The strain was based on the γ-PGA synthetase complex, PgsBCA, which is the only polyprotein complex responsible for γ-PGA synthesis in Bacillus spp. In the present study, PgsBCA was reconstituted and overexpressed in C. glutamicum to further enhance γ-PGA synthesis. First, we confirmed that all the components (PgsB, PgsC, and PgsA) of γ-PGA synthetase derived from B. licheniformis are necessary for γ-PGA synthesis, and γ-PGA was detected only when PgsB, PgsC, and PgsA were expressed in combination in C. glutamicum. Next, the expression level of each pgsB, pgsC, and pgsA was tuned in order to explore the effect of expression of each of the γ-PGA synthetase subunits on γ-PGA production. Results showed that increasing the transcription levels of pgsB or pgsC and maintaining a medium-level transcription level of pgsA led to 35.44% and 76.53% increase in γ-PGA yield (γ-PGA yield-to-biomass), respectively. Notably, the expression level of pgsC had the greatest influence (accounting for 68.24%) on γ-PGA synthesis, followed by pgsB. Next, genes encoding for PgsC from four different sources (Bacillus subtilis, Bacillus anthracis, Bacillus methylotrophicus, and Bacillus amyloliquefaciens) were tested in order to identify the influence of PgsC-encoding orthologues on γ-PGA production, but results showed that in all cases the synthesis of γ-PGA was significantly inhibited. Similarly, we also explored the influence of gene orthologues encoding for PgsB on γ-PGA production, and found that the titer increased to 17.14 ± 0.62 g/L from 8.24 ± 0.10 g/L when PgsB derived from B. methylotrophicus replaced PgsB alone in PgsBCA from B. licheniformis. The resulting strain was chosen for further optimization, and we achieved a γ-PGA titer of 38.26 g/L in a 5 L fermentor by optimizing dissolved oxygen level. Subsequently, by supplementing glucose, γ-PGA titer increased to 50.2 g/L at 48 h. To the best of our knowledge, this study achieved the highest titer for de novo production of γ-PGA from glucose, without addition of L-glutamic acid, resulting in a novel strategy for enhancing γ-PGA production.

Evaluation of some heavy metals and selenium pollution in Karataş Lake (Burdur/Türkiye) using various pollution indices and statistical analysis

Wetland face environmental problems due to some reasons such as drought, rapid population and rapid developments in technology. Karataş Lake is located within the Lakes Region in Türkiye and has also of great economically, ecologically and ornithologically importance. Unfortunately, it completely dried out in 2021 due to sufficient rainfall, groundwater withdrawal and global climate change. In 2022, the lake started to hold water again. This study is important because it is one of the last studies before the lake dries up and first study to evaluate some heavy metals and selenium pollution using some indices. In this study, which was carried out between October 2019–July 2020, some heavy metals and selenium concentrations were determined in water of Karataş Lake seasonally and evaluated pollution degree of lake water using some indices and statistical analysis. Water temperature, pH, electrical conductivity and dissolved oxygen levels were measured in situ using YSI 556 MPS. For heavy metal analysis, water samples were taken, acidified to a pH of <2, stored at 4 °C and analyzed directly using ICP-OES (Agilent 5110). Pb and Se in all seasons were below detection limit. The analyzed metals sorted as; Cd < Mo < Cr < Cu < Mn < Zn < Ni < Fe. Generally, heavy metals were increased in autumn and decreased in spring. According to some water quality standards for drinking water, Fe levels were higher than the permissible levels for drinking water in all seasons (TSE, 2005; EPA, 2018; EU, 2020), Mn in autumn (TSE, 2005; EPA, 2018; EU, 2020), Ni in autumn and summer (TSE, 2005; EU, 2020). Water Quality Index (WQI), Heavy Metal Pollution Index (HPI) and Heavy Metal Evaluation Index (HEI) values were calculated in Karataş Lake to determine pollution degree. Depend on WQI results, lake water was in good category in autumn, winter and spring while poor category in summer. The lake water samples based on HPI and HEI values are in the low contamination category. The lake is still struggling with environmental problems. If necessary precautions are not taken for the future of the lake, the lake may dry out again. The results of this study will help the authorities in terms of preventing re-drying, sustainability of the lake and management of the region. This study will be also a reference for future studies.

Synergistic interactions of zeolite, stocking density, and water exchange: A holistic approach to optimizing aquaculture performance of juvenile European seabass (Dicentrarchus labrax)

Effective water management is an essential component of sustainable fish farming practices, particularly in the context of global water scarcity. The accumulation of ammonium ions (NH4+) from fish metabolism necessitates frequent water changes, posing a challenge to the sustainability of fish farming operations. Zeolite materials have emerged as a promising solution, offering enhanced ammonium cation removal compared to conventional nitrifying bacteria. This innovative approach alleviates the pressure on water resources and promotes environmental sustainability in fish farming. Over 75 days, this study examined how zeolite, stocking density, and water exchange affected European seabass water quality and growth. 250 kg of seabass, 25.61 ± 2.39 g/fish. Three factors: zeolite levels (Z: 0, 10, and 15 ppt), density (D: 1, 2.5, and 5 kg/m3), and water exchange (W: 10, 25, and 50 %), using 81 hapas with 0.5 m3 vol each (triplicates for each treatment) fixed in concrete ponds, fish were randomly distributed among 81 experimental hapas in 27 ponds. This research illuminates the potential benefits of various therapies. Zeolite in seabass culture improved water quality. It reduced ammonia derivatives, improving water quality. Adjusting seabass stocking density to low or high improved water quality measures. This change kept dissolved oxygen levels within the target range, providing a good home for farmed fish. Zeolite supplements, reduced stocking density, and optimum water exchange improved European seabass growth, along with water quality improvements. These interventions improved feed consumption and growth rates. These approaches promoted fish growth and reduced stress by limiting the negative effects of high stocking density. The study also examined immune-related, hematobiochemical, and plasma biochemical characteristics after the interventions. Zeolite supplementation, to low stocking density, and water exchange improved these characteristics. They strengthened the European seabass' immune system and preserved healthy plasma and hematobiochemical parameters. In conclusion, optimizing European seabass culture with zeolite (15 ppt), stocking density (1 kg/m3), and water exchange (50 %) enhances water quality, growth performance, and physiological parameters. This contributes to improved aquaculture sustainability and efficiency. Further research is required to fully elucidate the molecular mechanisms of those factors that affect fish health and aquaculture practices.

Low carbon dioxide emissions from aquaculture farm of lake revealed by long-term measurements

Fast-growing global aquaculture has resulted in eco-environmental costs, one of the key concerns is carbon emissions. Freshwater lakes have been long used for aquaculture, and CO2 emissions from the system should be assessed to better understand the role of aquaculture in carbon budget. Here, CO2 emissions from aquaculture farm and open water of a lake in eastern China were investigated with long-term (2000–2017) field samplings. Positive correlation between annual CO2 emissions and dissolved organic carbon (R2 = 0.63, p < 0.01) occurred at aquaculture farm, suggesting feed-derived carbon application contributed to aquaculture CO2 emissions. But unexpected lower CO2 emissions (8.01 ± 5.28 mmol m−2 d−1) occurred at aquaculture farm compared with emissions from open water (11.58 ± 7.42 mmol m−2 d−1). Although temporal variation of CO2 emissions was negatively correlated with chlorophyll-a at non-aquaculture region, a reciprocal relationship with dissolved oxygen level (R2 = 0.35, p < 0.01) was found at aquaculture farm, which was attributed to the presence of aquatic vegetation used for the aquaculture. Meanwhile, positive correlation between annual CO2 emissions and nutrient was found, and aquatic vegetation planting in the aquaculture may reduce the CO2 emissions via direct photosynthesis and indirect ways of such as absorbing nutrient. The findings suggested that the two aquaculture management actions (feed addition and vegetation planting) are two antagonistic processes in the CO2 emissions, likely lead to the aquaculture farm as relatively low CO2 source. Our results may provide an informed solution for the tradeoff between CO2 emissions and aquaculture production.

The Impact of Anthropogenic Pollution on Tidal Water Quality in Mangrove Wetlands

Mangrove wetlands are vulnerable coastal ecosystems that provide critical habitats for aquatic life. Tai O is a popular tourist village on Lantau Island, Hong Kong, which is surrounded by mangrove wetlands with rich biodiversity; and this village is also famous for its traditional stilt houses. However, the untreated municipal sewage from some stilt houses is directly discharged into nearby tidal channels, potentially threatening health of the adjacent mangrove wetlands. In order to evaluate the anthropogenic impact on these wetlands and identify the potential sources of their pollution, this study aimed to evaluate spatial (at the sampling points) and temporal (during weekdays and weekends) differences in the quality of their tidal water, and examine relationships between the water quality and the density of the stilt houses. The results indicated that the water quality was worse during weekends. The ammonia concentrations in most samples exceeded the limits of the Hong Kong Water Quality Objectives, China’s Sea Water Quality Standards, and even the U.S. EPA criterion for fish reproduction. This high ammonia input could potentially adversely affect the mangrove ecosystem, underscoring the need for further comprehensive studies. Moreover, some of the weekend water samples had lower dissolved oxygen levels and were polluted by phosphate. Our Principal Component Analysis revealed that water quality was correlated with stilt house density, suggesting that anthropogenic inputs of untreated sewage was the major source of pollution. These findings highlight that nutrients released from human activities, particularly ammonia and phosphate, must be controlled for a better protection of mangrove wetland ecosystems.

Predicting dissolved oxygen level using Young's double-slit experiment optimizer-based weighting model

Accurate prediction of the dissolved oxygen level (DOL) is important for enhancing environmental conditions and facilitating water resource management. However, the irregularity and volatility inherent in DOL pose significant challenges to achieving precise forecasts. A single model usually suffers from low prediction accuracy, narrow application range, and difficult data acquisition. This study proposes a new weighted model that avoids these problems, which could increase the prediction accuracy of the DOL. The weighting constructs of the proposed model (PWM) included eight neural networks and one statistical method and utilized Young's double-slit experimental optimizer as an intelligent weighting tool. To evaluate the effectiveness of PWM, simulations were conducted using real-world data acquired from the Tualatin River Basin in Oregon, United States. Empirical findings unequivocally demonstrated that PWM outperforms both the statistical model and the individual machine learning models, and has the lowest mean absolute percentage error among all the weighted models. Based on two real datasets, the PWM can averagely obtain the mean absolute percentage errors of 1.0216%, 1.4630%, and 1.7087% for one-, two-, and three-step predictions, respectively. This study shows that the PWM can effectively integrate the distinctive merits of deep learning methods, neural networks, and statistical models, thereby increasing forecasting accuracy and providing indispensable technical support for the sustainable development of regional water environments.

A Comparative Assessment of the Physicochemical and Microbiological Qualities of Some Drinking Water Sources in Diobu, Portharcourt, Nigeria

Diseases caused as a results of drinking contaminated water pose a severe risk to the public's health. In the current study, various drinking water sources in Diobu, Port Harcourt, were evaluated and their microbiological and physicochemical characteristics were compared. Drinking water samples were collected from a borehole and a sachet (packaged) source. Physicochemical and bacteriological investigations were conducted using standard analytical techniques. The results of physiochemical parameters revealed that sachet water samples had higher pH values than borehole water. The borehole water samples had a mean pH of 4.37±1.21 which was much lower than the W.H.O.- recommended range (6.5-8.5). The study’s Total Suspended Solids readings were within the permissible limits of 30.0 mg/l. The borehole samples had the highest concentration of 6.5±4.31mg/l, while the sachet water samples had the lowest concentration of 2.5±1.5 mg/l. Total Dissolved Solids ranged between 15.8±13.5mg/l in sachet water and 55.6±33.4 mg/l in samples from boreholes. The Electrical Conductivity values were recorded as 33.5±28.4 µScm-1 in sachet water and 136.6±73.9 µScm-1 in borehole water. The mean total alkalinity value in sachet water was 0.57±0.29 mg/l whereas in borehole water, it was 3.29±1.39 mg/l. For sachet water and borehole water, the levels of water hardness ranged from 1.95±0.84 mg/l to 10.67±3.21 mg/l, respectively. The range of biological oxygen demand was &lt; 1±0.00 (for sachet water) to 2.13±13 (for borehole water). Dissolved oxygen levels ranged from 1.72±0.70 mg/l in sachet water to 1.95±0.62 mg/l in borehole water. Chemical oxygen demand levels ranged from 2.38±1.18mg/l (Sachet water) to 11.31±9.49 (Borehole water) while Turbidity ranged from &lt;1±0.00 NTU (Sachet water) to 1.1±0.64 NTU (Borehole water). Except for Chemical Oxygen Demand, there was no difference in the values that were observed that was significant at P≥ 0.05 in this study. The mean total bacterial counts ranged from 2.0 x 104 CFU/ml in sachet water to 9.0 x104 CFU/ml in borehole water, demonstrating high levels of contamination in the borehole water from human contamination. Comparatively to the other water sources, sachet water had the lowest overall bacterial and coliform levels. However, because the bacteriological values for total coliform counts was above the WHO threshold of zero per 100 ml, they did not comply with international standards. Salmonella spp., Pseudomonas spp., Staphylococcus spp., and Escherichia coli were the pathogenic bacteria of public health significance that were isolated from the diverse water samples. Five distinct isolates of fungi, including Penicillium spp., Aspergillus niger, Aspergillus flavus, Trichoderma spp., and Mucor spp., were found. In comparison to borehole water, which had the most bacterial pollutants, sachet water tests had the fewest. It is advised that the water sources be treated before being used for any domestic purposes as the water sources in this research area are not suitable for human consumption.

Assessment of Water Pollution in the Korotoa River: Implications for Ecosystems and Human Welfare in Bogura, Bangladesh

This study presents a comprehensive evaluation of water quality in the Korotoa River, crucial to Bogura, Bangladesh, as it serves as a critical water supply for the city. Despite its significance, the river faces considerable pollution concerns from untreated pollutants emitted by urban and adjacent regions. The research attempts to analyze the level of water pollution and its repercussions on aquatic ecosystems and human usage. Through systematic water sample collection at numerous locations, the project examines physical and chemical features. Results, assessed against environmental criteria, indicate low dissolved oxygen levels and unsatisfactory water quality measures, particularly around confluence locations. The study exposes significant water pollution, necessitating immediate action to maintain aquatic life, ecosystems, and community well-being. Urgent pollution control actions are necessary to restore and preserve the Korotoa River’s natural balance in Bogura, emphasizing the need for education, monitoring, and research. The research provides insights for authorities and stakeholders to reduce pollution, sustaining the river’s critical role in the region’s biodiversity, agriculture, and human activities.

Evaluation of the Effect of Microalgae Chlorella vulgaris on the Performance of Membrane Bioreactor for Industrial Wastewater Treatment

Water pollution, especially from industry, is a problem that continues to emerge and even get worse. Rising sludge events often occur in industrial wastewater treatment processes. Process engineering with the addition of microalgae is proposed in this study to overcome the occurrence of rising sludge and improve wastewater quality based on dissolved oxygen levels. The control variables used were MLSS 1000 mg/L, microalgae Chlorella vulgaris 106 L, and urea and TSP 1,75 kg each. The dependent variable is rising sludge and DO levels while the independent variable is time. This research went through several stages, namely seeding microalgae, seeding microalgae into activated sludge in MBBR, experimenting with combining microalgae and activated sludge in MBBR, and installing ultrafiltration membranes with a WWTP capacity of 150 m3/day. The addition of microalgae in the MBBR process has a positive impact in improving the quality of industrial wastewater, which is characterized by the absence of rising sludge and DO levels exceeding the minimum threshold.

Optimization of human urine to synthetic wastewater ratio for pollutants removal, power generation in a bioelectrochemical system

When the human urine is mixed with the domestic wastewater, it leads to 70 % increase in nitrate level and 50 % increase in phosphorus level in the domestic sewage. So, the treatment of municipal sewage becomes more expensive and energy-intensive. Human urine is a waste and contributes to only 1 % (v) of domestic municipal wastewater, but yet it contributes 75 % nitrogen, 50 % phosphorus and 10 % chemical oxygen demand (COD) in the entire municipal wastewater. In this study, the optimization studies of human urine to synthetic wastewater ratio for power generation and pollutant removal in a dual chamber microbial fuel cell (MFC) is investigated. As diluted human urine has shown promising results in terms of power generation, current studies carried out the investigation by feeding the MFC with raw human urine diluted by synthetic wastewater in various ratios. Over the course of 336 h, the MFC were operated in batch mode. Along with bioelectricity generation and COD removal, certain physic-chemical parameters like pH, electrical conductivity, and dissolved oxygen levels were also assessed on a regular basis. A maximal power production of 7.74 W/m2 was achieved in the final batch scale with human urine and synthetic wastewater of 2:7 ratio, whereas a quite lower power generation, i.e., 1.64 W/m2, was reported in the first batch scale with urine and synthetic wastewater in a 1:8 ratio. The initial batch scale, which used synthetic wastewater and urine in a 1:8 ratio as feed, attained a maximum COD reduction of 50 %.

Investigating the Stirred Tank Bioreactor Co-Cultures of the Secondary Metabolite Producers Streptomyces noursei and Penicillium rubens.

The stirred tank bioreactor co-cultures of the filamentous fungus Penicillium rubens and actinomycete Streptomyces noursei were studied with regard to secondary metabolite (SM) production, sugar consumption, and dissolved oxygen levels. In addition to the quantitative analysis of penicillin G and nystatin A1, the broad repertoire of 22 putatively identified products was semi-quantitatively evaluated with the use of UPLC-MS. Three co-cultivation variants differing with respect to the co-culture initiation method (i.e., the simultaneous inoculation of P. rubens and S. noursei and the 24 or 48 h inoculation delay of S. noursei relative to P. rubens) were investigated. All the co-cultures were carried out in parallel with the corresponding monoculture controls. Even though S. noursei showed the tendency to outperform P. rubens and inhibit the production of fungal secondary metabolites, the approach of simultaneous inoculation was effective in terms of enhancing the production of some S. noursei SMs, namely desferrioxamine E, deshydroxynocardamine, and argvalin. S. noursei displayed the capability of adaptation and SM production even after being inoculated into the 24 or 48 h culture of P. rubens. Interestingly, S. noursei turned out to be more efficient in terms of secondary metabolite production when its inoculation time relative to P. rubens was delayed by 48 h rather than by 24 h. The study demonstrated that the prolongation of inoculation delays can be beneficial for production-related performance in some co-culture systems.

Optimizing Mangrove Conservation through Integrated Landscape Management in Kota Karang, Bandar Lampung

Mangrove degradation in Bandar Lampung, specifically Kota Karang, Teluk Betung Timur, has left only 9,86% or 6 hectares, causing habitat loss and increased greenhouse gas emissions. This study identifies deficiencies in the government-led mangrove management system, emphasizing individual management leading to overlapping responsibilities and a lack of coordination. The research method employed is descriptive qualitative, incorporating primary data from observations, interviews, and documentation, alongside secondary data and literature studies. Observations encompass the assessment of biophysical elements, ecological indicators, and mangrove reduction due to land conversion. Literature studies focus on identifying soil types, water pH, dissolved oxygen levels, mangrove vegetation types, and principles of integrated landscape management. SWOT (Strength, Weakness, Opportunity, Threats) analysis considers stakeholders roles, disaster risks, land conversion, pollution, over-exploitation, and community participation. Findings prompt five strategies: community empowerment, eco-friendly tourism, cross-sector cooperation, enhanced monitoring, and mangrove rehabilitation. Recommendations, rooted in integrated landscape management, target all stakeholders, with a focus on government involvement. This holistic approach addresses identified issues, striving for enhanced mangrove ecosystem sustainability through collaborative efforts and strategic planning, emphasizing the need for coordinated stakeholders action in mangrove conservation.