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In aquatic environments, excessive amounts of inorganic nutrients, such as heavy metals, pose a metabolic risk and threaten to halt microbial activity. Metal-resistant bacteria, through various metabolic activities, can treat and detoxify harmful inorganic compounds. Thus, higher energy and electron transport system (ETS) demands may be necessary for metal bioremediation, but cell viability may be affected. Therefore, the metabolic respiration activity of cells in the presence of Cu, Zn, Ni, and Cr individually and in the quaternary is an important aspect of this study that relies on estimating the action of respiration enzymes responsible for metabolic activity and glucose reduction over periods of metallic stress and growth phases. Three species of bacteria, including B. megaterium, S. ginsenosidimutans, and K. rhizophila, were isolated from the electroplating effluent and used to determine the activity level of catalase, dehydrogenase enzymes, and glucose reduction. Their ability to sustain metabolic activity and understand their role in conferring tolerance and bioremediation capabilities to bacteria was evaluated. The findings revealed that metabolic activity was greater during the exponential phase than during the stationary phase. Catalase production was less affected by high metal levels; additionally, sugar reduction was improved but decreased with increased metal levels, and growth progressed, in comparison to dehydrogenase activity, which was more sensitive to high metal levels. Although respiratory metabolism activity decreased with increasing cell age and high metal concentrations, metabolism and viability persisted under metallic stress. This establishes the tolerability of bacteria and recommends them for potential bioremediation of metallic pollutants and environmental clean-up. [ABSTRACT FROM AUTHOR]

There is a paucity of published research information on the quality of water used in the Malaysian ruminant livestock production system. Also, there are growing concerns about the sanitation standards of ruminant farms as it affects the management of wastewater in Malaysia. This study was designed to compile preliminary data on the drinking water and wastewater quality in designated dairy cattle farms in the Klang Valley. Seven dairy farms were randomly selected and visited to collect samples of drinking and wastewater for laboratory analysis. The water samples were analyzed to determine dissolved oxygen (DO), pH, salinity, electrical conductivity, turbidity, biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total dissolved solids (TDS), ammoniacal nitrogen, nitrate, phosphates, total coliform count, iron, and magnesium content. The means of various parameters were compared with the National Water Quality Standards (NWQS) to determine the appropriate classification. We further streamlined the rating of water quality into three broad categories, namely, good (Class I and II), moderate (Class III) and unsatisfactory (Class IV and V). Analysis of drinking water revealed 1(14.29%), 2 (28.57%), 2 (28.57%) and 2 (28.57%) farms were categorized as Class II, III, IV and V, respectively. Meanwhile, all the wastewater samples analyzed in this study were classified as Class V. This study provides preliminary data on the quality of drinking and wastewater in select dairy cattle farms in Malaysia. The obtained findings indicate that the quality of drinking water in most of the cattle farms is below the National Water Quality Standa [ABSTRACT FROM AUTHOR]

Water is an essential part in any livestock production and it is more so in ruminant production that is highly water intensive. Water is not only essential as a medium of animal metabolism, but it is also an important cleaning medium. Therefore, it is important that the quality of drinking water is maintained at a certain level so as to lessen the possible adverse effects on the animals. Despite there has being some standards set by the various agencies on the minimal water quality deemed suitable for livestock consumption, they are still vague and this, combined with poor compliance and the water sourcing of dubious sources in ruminant farms makes it hard to regulate the drinking water quality in ruminant farms. This, in turn, might lead to possible adverse effects in livestock production due to water contaminants. At the same time, most ruminant farms in Malaysia do not do proper treatment of their wastewater before releasing them into water bodies such as drains, rivers and lakes which could lead to possible adverse effects to the environment. [ABSTRACT FROM AUTHOR]

The increase of anthropogenic activities and growth of technology in Antarctica is fuelled by the high demand for petroleum hydrocarbons needed for daily activities. Oil and fuel spills that occur during explorations have caused hydrocarbon pollution in this region, prompting concern for the environment by polar communities and the larger world community. Crude oil and petroleum hydrocarbon products contain a wide variety of lethal components with high toxicity and low biodegradability. Hydrocarbon persistence in the Antarctic environment only worsens the issues stemming from environmental pollution as they can be long-term. Numerous efforts to lower the contamination level caused by these pollutants have been conducted mainly in bioremediation, an economical and degrading-wise method. Bioremediation mainly functions on conversion of complex toxic compounds to simpler organic compounds due to the consumption of hydrocarbons by microorganisms as their energy source. This review presents a summary of the collective understanding on bioremediation of petroleum hydrocarbons by microorganisms indigenous to the Antarctic region from past decades to current knowledge. [ABSTRACT FROM AUTHOR]

The performance of the centrifuge dewatering unit in Sungai Udang centralized sludge treatment facility has been studied using multivariate statistical approach. The relationships between bio-solids production and 14 parameters were analyzed using principle component analysis (PCA) and multiple linear regression (MLR) analysis. PCA was used to simplify the complexity among variables affecting the production of bio-solids in the treatment facility. All varimax factor (VF) values obtained from the PCA were used as independent variables in MLR analysis. It was found that VF1 (wet sludge and mixed liquor suspended solids) and VF4 (polymer dosage) had significant linear relationships with bio-solids production, which accounted for 74.32% of variations in the bio-solids production. This approach could be used to precisely estimate the amount of sludge produced by the centrifuge dewatering unit and for better evaluation of system performance that meets the design criteria and future requirements for sludge disposal. [ABSTRACT FROM PUBLISHER]