Sudden Increase and Regrowth of Fecal Coliforms and Escherichia Coli in Wastewater Biosolids After High Solids Centrifugation

Treatment plants that operate either thermophilic or mesophilic anaerobic digesters with centrifugal dewatering processes have consistently observed densities of fecal coliform and Escherichia coli, both indicator bacteria, that decrease during digestion but then increase after dewatering and storage. The increases have been characterized as two separate phenomena to explain this observation: 1) “Sudden Increase,” or SI, which is defined as the increase that occurs immediately after dewatering and 2) “regrowth,” which is defined as an increase during storage of cake samples over a period of hours or days. The SI observation appears to be more prevalent with biosolids that are generated with thermophilic processes and dewatered by centrifugation. Both thermophilic and mesophilic digesters with centrifuge dewatering processes have observed the regrowth phenomena. This research hypothesizes that the SI phenomenon is due to the presence of viable nonculturable (VNC) bacteria that are reactivated during dewatering. In other words, the bacteria were always present but were not enumerated by standard culturing methods (SCM). Analysis of the E. coli density in thermally treated solids by SCMs and quantitative real-time polymerase chain reaction (qPCR) indicated that E. coli densities are often underestimated by SCM. When analyzed with qPCR, the E. coli density after digestion can be 4-5 orders of magnitude greater than the non-detect levels identified by SCMs, which supports the non-culturable hypothesis. The VNC state describes a condition where bacteria are alive but unable to sustain the metabolic process needed for cellular division. Supplements added to culturing media were investigated to determine if the resuscitation of VNC bacteria could be enhanced. The autoinducer molecules Nhexanoyl- L-Homoserine lactone (C6-HSL), 3-oxo-N-octanoyl-L-Homoserine lactone (3-oxo- C8-HSL), and norepinephrine were unable to induce the resuscitation of VNC E. coli. Additional sampling was performed to determine if autoinducer molecules, peroxides, or other as of yet unknown inhibitory agents and toxins could be removed from biosolids during SCM. Culture media supplemented with the peroxide degrading compounds catalase, α-ketoglutaric acid, and sodium pyruvate was unable to resuscitate non-culturable E. coli. The additions of bentonite and exponential growth phase E. coli cell-free supernatant to culturing media were also unable to increase the culturability of E. coli. To remove inhibitory agents and toxins, a cell washing technique was employed prior to performing SCM; however, this cell washing technique may have increased cellular stresses that inhibited resuscitation since cell densities decreased. A novel laboratory-scale dewatering process was also investigated to determine if the SI and regrowth phenomena observed in full-scale centrifugal dewatering could be mimicked in the laboratory using a lab shearing device. Fecal coliform and E. coli densities in laboratory prepared cake samples were observed to be an order of magnitude higher than full-scale dewatered cakes. Additionally, the laboratory-scale dewatering process was able to resuscitate fecal coliforms and E. coli in stored sludge such that the density increased by 4-5 orders of magnitude from nondetect values. Lastly, the addition of aluminum sulfate during centrifuge dewatering at a full-scale utility produced an increased regrowth of fecal coliforms and E. coli that was sustained for 5 days.

Coffee inhibits the reactivation of glucocorticoids by 11beta-hydroxysteroid dehydrogenase type 1: a glucocorticoid connection in the anti-diabetic action of coffee?

Recent epidemiological studies demonstrated a beneficial effect of coffee consumption for the prevention of type 2 diabetes, however, the underlying mechanisms remained unknown. We demonstrate that coffee extract, corresponding to an Italian Espresso, inhibits recombinant and endogenous 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) activity. The inhibitory component is heat-stable with considerable polarity. Coffee extract blocked 11beta-HSD1-dependent cortisol formation, prevented the subsequent nuclear translocation of the glucocorticoid receptor and abolished glucocorticoid-induced expression of the key gluconeogenic enzyme phosphoenolpyruvate carboxykinase. We suggest that at least part of the anti-diabetic effects of coffee consumption is due to inhibition of 11beta-HSD1-dependent glucocorticoid reactivation.

The impact of balsamo (Myroxylon balsamum L. Harms) on coffee yield and household income in El Balsamar, El Salvador

El Balsamar is a community that relies upon coffee trees intercropped with the balsamo tree (Myroxylon balsamum L. Harms) for a substantial portion of household income. The balsamo tree is valued for its resin which is used as medicine in the community and sold commercially. Farmers believe that the shade from the balsamo tree decreases coffee yield compared to the shade from non balsamo species. Thirty coffee farms were studied, each set up as a paired plot. When cover type was balsamo, coffee yield was more likely to decrease. Plots with higher basal area were more likely to be balsamo cover type. As basal area increased, coffee yield decreased. Although coffee yield is lower under balsamo cover type, farmers still continue to plant and manage coffee under this cover type. Farmers accept a lower coffee yield because balsamo resin provides an important income source. Farmers rely on the community cooperative to provide them work to support their households. The cooperative relies on the farmers to provide the labor needed to harvest coffee and extract balsamo resin.

Ethanol Production from Hardboard Manufacturing Process Wastewater: Methods for Improving Product Yields from Hemicellulose Hydrolysates

Waste effluents from the forest products industry are sources of lignocellulosic biomass that can be converted to ethanol by yeast after pretreatment. However, the challenge of improving ethanol yields from a mixed pentose and hexose fermentation of a potentially inhibitory hydrolysate still remains. Hardboard manufacturing process wastewater (HPW) was evaluated at a potential feedstream for lignocellulosic ethanol production by native xylose-fermenting yeast. After screening of xylose-fermenting yeasts, Scheffersomyces stipitis CBS 6054 was selected as the ideal organism for conversion of the HPW hydrolysate material. The individual and synergistic effects of inhibitory compounds present in the hydrolysate were evaluated using response surface methodology. It was concluded that organic acids have an additive negative effect on fermentations. Fermentation conditions were also optimized in terms of aeration and pH. Methods for improving productivity and achieving higher ethanol yields were investigated. Adaptation to the conditions present in the hydrolysate through repeated cell sub-culturing was used. The objectives of this present study were to adapt S. stipitis CBS6054 to a dilute-acid pretreated lignocellulosic containing waste stream; compare the physiological, metabolic, and proteomic profiles of the adapted strain to its parent; quantify changes in protein expression/regulation, metabolite abundance, and enzyme activity; and determine the biochemical and molecular mechanism of adaptation. The adapted culture showed improvement in both substrate utilization and ethanol yields compared to the unadapted parent strain. The adapted strain also represented a growth phenotype compared to its unadapted parent based on its physiological and proteomic profiles. Several potential targets that could be responsible for strain improvement were identified. These targets could have implications for metabolic engineering of strains for improved ethanol production from lignocellulosic feedstocks. Although this work focuses specifically on the conversion of HPW to ethanol, the methods developed can be used for any feedstock/product systems that employ a microbial conversion step. The benefit of this research is that the organisms will the optimized for a company's specific system.

Organic Wastewater Chemicals in Silver Bow Creek - Butte to Warm Springs Ponds

The purpose of this study is to detail and analyze the distribution, concentration, and loads of 5 organic compounds along Silver Bow Creek in Butte, Montana from the Municipal Wastewater treatment plant to the Warm Springs Ponds. The chemicals analyzed include Carbamazepine (pharmaceutical), Miconazole (fungicide) and three antibiotics – Sulfamethoxazole, Thiabendazole, and Ciprofloxacin. This project begins a 2 year study to analyze 6 additional compounds (11 compounds total), to develop an effective method to detail and analyze OWCs using Mass Spectrometer/Liquid chromatography system, and to aid in assessment of aquatic health and ongoing restoration work. The EPA method 1694 was used for analysis

Bioavailability of pharmaceuticals in waters close to wastewater treatment plants: use of fish bile for exposure assessment

Pharmaceuticals are ubiquitous in surface waters as a consequence of discharges from municipal wastewater treatment plants. However, few studies have assessed the bioavailability of pharmaceuticals to fish in natural waters. In the present study, passive samplers and rainbow trout were experimentally deployed next to three municipal wastewater treatment plants in Finland to evaluate the degree of animal exposure. Pharmaceuticals from several therapeutic classes (in total 15) were analyzed by liquid chromatography-tandem mass spectrometry in extracts of passive samplers and in bile and blood plasma of rainbow trout held at polluted sites for 10 d. Each approach indicated the highest exposure near wastewater treatment plant A and the lowest near that of plant C. Diclofenac, naproxen, and ibuprofen were found in rainbow trout, and their concentrations in bile were 10 to 400 times higher than in plasma. The phase I metabolite hydroxydiclofenac was also detected in bile. Hence, bile proved to be an excellent sample matrix for the exposure assessment of fish. Most of the monitored pharmaceuticals were found in passive samplers, implying that they may overestimate the actual exposure of fish in receiving waters. Two biomarkers, hepatic vitellogenin and cytochrome P4501A, did not reveal clear effects on fish, although a small induction of vitellogenin mRNA was observed in trout caged near wastewater treatment plants B and C.

Coffee consumption attenuates short-term fructose-induced liver insulin resistance in healthy men.

BACKGROUND Epidemiologic and experimental data have suggested that chlorogenic acid, which is a polyphenol contained in green coffee beans, prevents diet-induced hepatic steatosis and insulin resistance. OBJECTIVE We assessed whether the consumption of chlorogenic acid-rich coffee attenuates the effects of short-term fructose overfeeding, dietary conditions known to increase intrahepatocellular lipids (IHCLs), and blood triglyceride concentrations and to decrease hepatic insulin sensitivity in healthy humans. DESIGN Effects of 3 different coffees were assessed in 10 healthy volunteers in a randomized, controlled, crossover trial. IHCLs, hepatic glucose production (HGP) (by 6,6-d2 glucose dilution), and fasting lipid oxidation were measured after 14 d of consumption of caffeinated coffee high in chlorogenic acid (C-HCA), decaffeinated coffee high in chlorogenic acid, or decaffeinated coffee with regular amounts of chlorogenic acid (D-RCA); during the last 6 d of the study, the weight-maintenance diet of subjects was supplemented with 4 g fructose · kg(-1) · d(-1) (total energy intake ± SD: 143 ± 1% of weight-maintenance requirements). All participants were also studied without coffee supplementation, either with 4 g fructose · kg(-1) · d(-1) (high fructose only) or without high fructose (control). RESULTS Compared with the control diet, the high-fructose diet significantly increased IHCLs by 102 ± 36% and HGP by 16 ± 3% and decreased fasting lipid oxidation by 100 ± 29% (all P < 0.05). All 3 coffees significantly decreased HGP. Fasting lipid oxidation increased with C-HCA and D-RCA (P < 0.05). None of the 3 coffees significantly altered IHCLs. CONCLUSIONS Coffee consumption attenuates hepatic insulin resistance but not the increase of IHCLs induced by fructose overfeeding. This effect does not appear to be mediated by differences in the caffeine or chlorogenic acid content. This trial was registered at clinicaltrials.gov as NCT00827450.

Adaptation to Changes in the Coffee Value Chain and the Price of Coiffee among Coffee Producers in Two Villages in Kilimanjaro, Tanzania

Market liberalization in Tanzania has eroded the monopoly of the cooperative unions by allowing private coffee buyers (PCBs) to compete with them on equal footing. Similarly, farmers groups and primary societies are now allowed to sell coffee at auction. Thus, farmers have various options for selling their coffee. Similarly, the coffee industry has experienced large fluctuations in prices and stagnation in production. How do farmers react to these changes? Can and do farmers profit from different market conditions and sell to different traders at the lower end of the value chain, or do they remain with cooperatives or farmers groups? This study was conducted in Mruwia and Mshiri villages in Moshi Rural district. Whereas Mshiri village remains attached to the Kilimanjaro Native Cooperative Union (KNCU), Mruwia has detached from this organization and sells coffee independently. The sample (103) was randomly selected from the coffee farmers in the two villages. Data were collected through surveys, focus group discussions (FGDs), and socio-anthropological methods (participant-observation, biographies, and thematic interviews). Results indicate that the selection of whom to sell coffee depends largely on farmers’ dependence on coffee and prices, other benefits accrued, and whether the initial costs are covered by buyers. Additionally, most respondents did not sell coffee to PCBs. Thus, prices, the institutional infrastructure, and the structure of local communities were important when making decisions about how and with whom to trade.

Sustainable Wastewater Management: Is it Possible to Regulate Micropollution in the Future by Learning from the Past? A Policy Analysis

This paper applies a policy analysis approach to the question of how to effectively regulate micropollution in a sustainable manner. Micropollution is a complex policy problem characterized by a huge number and diversity of chemical substances, as well as various entry paths into the aquatic environment. It challenges traditional water quality management by calling for new technologies in wastewater treatment and behavioral changes in industry, agriculture and civil society. In light of such challenges, the question arises as to how to regulate such a complex phenomenon to ensure water quality is maintained in the future? What can we learn from past experiences in water quality regulation? To answer these questions, policy analysis strongly focuses on the design and choice of policy instruments and the mix of such measures. In this paper, we review instruments commonly used in past water quality regulation. We evaluate their ability to respond to the characteristics of a more recent water quality problem, i.e., micropollution, in a sustainable way. This way, we develop a new framework that integrates both the problem dimension (i.e., causes and effects of a problem) as well as the sustainability dimension (e.g., long-term, cross-sectoral and multi-level) to assess which policy instruments are best suited to regulate micropollution. We thus conclude that sustainability criteria help to identify an appropriate instrument mix of end-of-pipe and source-directed measures to reduce aquatic micropollution.

Land acquisition, investment, and development in the Lao coffee sector: Successes and failures

Despite the increasing acknowledgment of scholars and practitioners that many large-scale agricultural land acquisitions in developing countries fail or never materialize, empirical evidence about how and why they fail to date is still scarce. Too often, land deals are portrayed as straightforward investments and their success is taken for granted. Looking at the coffee sector in Laos, the authors of this article explore dimensions of the land grab debate that have not yet been sufficiently examined. Coffee concessionaires in southern Laos often fail to use all of the land granted them and fail to produce high yields on the land they do use. Thus, the authors challenge the often-assumed superiority and effectiveness of large-scale versus small-scale production, specifically the argument that they modernize agricultural production and optimize land use. They argue that examining failed investments is as important as studying successful ones for understanding the implications of the land grabbing phenomenon for social, economic, and environmental outcomes. Knowledge about the scale of “failed land deals” provides important motivation for national governments to close the gap between intentions and actual outcomes. This article engages with the current debate on quality of investment and challenges the approach of employing land concessions as a vehicle for economic development in the Lao coffee sector and in other sectors and countries.

Partitioning the Choice Task Makes Starbucks Coffee Taste Better

Consumers are often less satisfied with a product chosen from a large assortment than a limited one. Experienced choice difficulty presumably causes this as consumers have to engage in a great number of individual comparisons. In two studies we tested whether partitioning the choice task so that consumers decided sequentially on each individual attribute may provide a solution. In a Starbucks coffee house, consumers who chose from the menu rated the coffee as less tasty when chosen from a large rather than a small assortment. However, when the consumers chose it by sequentially deciding about one attribute at a time, the effect reversed. In a tailored-suit customization, consumers who chose multiple attributes at a time were less satisfied with their suit, compared to those who chose one attribute at a time. Sequential attribute-based processing proves to be an effective strategy to reap the benefits of a large assortment.