indicator organisms
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Horticulturae ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 20
Author(s):  
Renee M. Holland ◽  
Jinru Chen ◽  
Himabindu Gazula ◽  
Harald Scherm

Although previous studies have examined microbial loads on food contact surfaces in blueberry packing plants, there is currently no information regarding microbial risks associated with mechanical berry harvesters used in commercial blueberry production. In this study, we surveyed up to nine fruit contact surfaces on seven mechanical harvesters in each of 2015 and 2016 in the field. These surfaces included the shaking rods at the front of the harvester, the sidewalls of the harvesting tunnel behind the shaking mechanism, the catcher plates collecting the detached berries, horizontal and vertical fruit conveyor belts, and berry lugs collecting the fruit at the back of the harvester. Swab samples were collected from each surface three times a day (morning, noon, and evening) and assessed for environmental and fecal indicator organisms including total aerobes, total yeasts and molds, coliforms and fecal coliforms, and enterococci. At the same time points, fruit samples were assessed for microbial loads before the fruit entered each harvester and after they exited the harvester. Results showed statistically significant differences in microbial loads among harvester surfaces, whereas the effect of sampling time was generally not significant. High levels of total aerobes and total yeasts and molds were recorded, especially on horizontal surfaces and/or those located at the bottom of the harvester such as the lower sidewall, the catcher plates, and the horizontal conveyor belt. These surfaces therefore should be targeted by cleaning and sanitization practices. There was also statistical evidence that passage through the harvester may increase the levels of the environmental microorganisms on fruit in the field. In contrast, fecal indicator organisms such as fecal coliforms and enterococci were detected only sporadically and at very low densities on harvester surfaces and blueberry fruit, and there was no evidence that passage through the harvester increased their levels on the fruit. Berry lugs consistently harbored microbial loads, and given their movement back and forth between the field and the packing plant, deserve particular attention with regard to cleaning, sanitization, and storage protocols.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0258898
Author(s):  
Cascade Tuholske ◽  
Benjamin S. Halpern ◽  
Gordon Blasco ◽  
Juan Carlos Villasenor ◽  
Melanie Frazier ◽  
...  

Coastal marine ecosystems face a host of pressures from both offshore and land-based human activity. Research on terrestrial threats to coastal ecosystems has primarily focused on agricultural runoff, specifically showcasing how fertilizers and livestock waste create coastal eutrophication, harmful algae blooms, or hypoxic or anoxic zones. These impacts not only harm coastal species and ecosystems but also impact human health and economic activities. Few studies have assessed impacts of human wastewater on coastal ecosystems and community health. As such, we lack a comprehensive, fine-resolution, global assessment of human sewage inputs that captures both pathogens and nutrient flows to coastal waters and the potential impacts on coastal ecosystems. To address this gap, we use a new high-resolution geospatial model to measure and map nitrogen (N) and pathogen—fecal indicator organisms (FIO)—inputs from human sewage for ~135,000 watersheds globally. Because solutions depend on the source, we separate nitrogen and pathogen inputs from sewer, septic, and direct inputs. Our model indicates that wastewater adds 6.2Tg nitrogen into coastal waters, which is approximately 40% of total nitrogen from agriculture. Of total wastewater N, 63% (3.9Tg N) comes from sewered systems, 5% (0.3Tg N) from septic, and 32% (2.0Tg N) from direct input. We find that just 25 watersheds contribute nearly half of all wastewater N, but wastewater impacts most coastlines globally, with sewered, septic, and untreated wastewater inputs varying greatly across watersheds and by country. Importantly, model results find that 58% of coral and 88% of seagrass beds are exposed to wastewater N input. Across watersheds, N and FIO inputs are generally correlated. However, our model identifies important fine-grained spatial heterogeneity that highlight potential tradeoffs and synergies essential for management actions. Reducing impacts of nitrogen and pathogens on coastal ecosystems requires a greater focus on where wastewater inputs vary across the planet. Researchers and practitioners can also overlay these global, high resolution, wastewater input maps with maps describing the distribution of habitats and species, including humans, to determine the where the impacts of wastewater pressures are highest. This will help prioritize conservation efforts.Without such information, coastal ecosystems and the human communities that depend on them will remain imperiled.


Author(s):  
Ainslie J. Butler ◽  
Katarina Pintar ◽  
Janis L. Thomas ◽  
Manon Fleury ◽  
Stefanie Kadykalo ◽  
...  

Abstract Recreational water use is an important source of human enteric illness. Enhanced (episodic) surveillance of natural recreational waters as a supplement to beach monitoring can enrich our understanding of human health risks. From 2011 to 2013, water sampling was undertaken at recreational sites on a watershed in eastern Canada. This study compared the prevalence and associations of human enteric pathogens and fecal indicator organisms. Beach water samples had lower pathogen presence than those along the main river, due to different pollution sources and the hydrological disposition. Pathogen profiles identified from the beach sites suggested a more narrow range of sources, including birds, indicating that wild bird management could help reduce public health risks at these sites. The presence and concentration of indicator organisms did not differ significantly between beaches and the river. However, higher concentrations of generic Escherichia coli were observed when Salmonella and Cryptosporidium were present at beach sites, when Salmonella was present at the river recreational site, and when verotoxigenic E. coli were present among all sites sampled. In this watershed, generic E. coli concentrations were good indicators of potential contamination, pathogen load, and elevated human health risk, supporting their use for routine monitoring where enhanced pathogen testing is not possible.


Author(s):  
З.Е. Мащенко ◽  
В.В. Бахарев ◽  
Ю.А. Егорова ◽  
О.И. Нестеренко ◽  
Я.М. Русских

Видовой состав активного ила зависит от множества абиотических и биотических факторов. На сегодняшний день появилась проблема возникновения в сточных водах остатков фармацевтических препаратов, которые негативно влияют на организмы активного ила, осуществляющего биологическую очистку воды. Лекарственными средствами, вызывающими нарушения метаболизма активного ила и приводящими к снижению степени очистки воды, являются антибиотики. Эти вещества снижают выживаемость и размножение некоторых видов организмов, а также приводят к развитию резистентности у бактерий. Приведены результаты исследований по воздействию бензилпенициллина натриевой соли на гидробионты активного ила при однократном и многократном воздействии в течение 72 часов. Проведена оценка общих свойств ила – цвет, запах, возможность вспухания, седиментационные свойства. Для исследования биоценоза ила использовали метод «раздавленная капля» при увеличении ×1000. При анализе микроскопических препаратов учитывали количество гидробионтов активного ила и их общее состояние. В качестве индикаторных организмов использовали следующие виды: амебы голые Amoeba, раковинные Testacea, жгутиковые Flagellata, коловратки Rotaria, инфузории Vaginicola,Epistylis и Aspidisca, черви Nematoda и Oligоchaeta, тихоходки, нитчатые бактерии. Полученные данные свидетельствовали об удовлетворительной работе активного ила в условиях эксперимента. Однако при многократном добавлении бензилпенициллина натриевой соли возможно ухудшение процессов нитрификации. The species composition of activated sludge depends on many abiotic and biotic factors. To date, there is a problem of the presence of trace pharmaceuticals in wastewater that negatively affect the organisms of activated sludge performing biological water treatment. Antibiotics are drugs that cause disturbances in the metabolism of activated sludge and lead to a decrease in the level of water treatment. These substances inhibit the survival and reproduction of some types of organisms, and also result in the development of resistance in bacteria. The results of studies on the effect of benzylpenicillin sodium salt on hydrobionts of activated sludge with single and repeated exposure within 72 hours are presented. The general properties of the sludge – color, smell, bulking, sedimentation – were estimated. To study the sludge biocenosis, we used the «crushed drop» method with a magnification of ×1000. While analyzing the microscopic slides, the number of hydrobionts of activated sludge and their general condition were taken into account. The following species were used as indicator organisms: naked amoeba Amoeba, testate Testacea, flagellate Flagellata, rotifers Rotaria, infusoria Vaginicola, Epistylis and Aspidisca, worms Nematodaand Oligоchaeta, tardigrades, filamentous bacteria. The obtained data testified to the satisfactory operation of the activated sludge under the experimental conditions. However, with repeated addition of benzylpenicillin sodium salt, the nitrification processes may deteriorate.


2021 ◽  
Vol 7 (3) ◽  
pp. 30-35
Author(s):  
J Nakamya ◽  
◽  
J.B Tumuhairwe ◽  
E.N Sabiiti ◽  
J Nakanwagi ◽  
...  

A screen house pot study using bio-slurry at the rate of 7.8 t N / ha was conducted at Makerere University Agricultural Research Institute (MAURIK) Kabanyolo, Uganda. This was monitored using fecal indicator organisms (coliforms, Escherichia coli and Enterococci) in loamy sand, sandy loam and sandy clay loam texture obtained at the study site within 5litres pots under a Complete Randomized Design under a screenhouse. The different textures significantly (p<0.05) reduced the fecal indicator organisms. Conditions within the loamy sand texture reduced the pathogenic microorganisms within 90 days due to its high sand content. In this soil texture, E. coli and enterococci were reduced to undetectable levels within 90 days unlike the coliforms. Fecal, Bio slurry, coliforms, Escherichia. coli, Enterococci


Author(s):  
Vince A. Chukwu ◽  
Jo U. Smith ◽  
Norval J. C. Strachan ◽  
Lisa M. Avery ◽  
Smart O. Obiekezie

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1403
Author(s):  
Diego E. Casas ◽  
Rosine Manishimwe ◽  
Savannah J. Forgey ◽  
Keelyn E. Hanlon ◽  
Markus F. Miller ◽  
...  

As the global meat market moves to never frozen alternatives, meat processors seek opportunities for increasing the shelf life of fresh meats by combinations of proper cold chain management, barrier technologies, and antimicrobial interventions. The objective of this study was to determine the impact of spray and dry chilling combined with hot water carcass treatments on the levels of microbial indicator organisms during the long-term refrigerated storage of beef cuts. Samples were taken using EZ-Reach™ sponge samplers with 25 mL buffered peptone water over a 100 cm2 area of the striploin. Sample collection was conducted before the hot carcass wash, after wash, and after the 24 h carcass chilling. Chilled striploins were cut into four sections, individually vacuum packaged, and stored to be sampled at 0, 45, 70, and 135 days (n = 200) of refrigerated storage and distribution. Aerobic plate counts, enterobacteria, Escherichia coli, coliforms, and psychrotroph counts were evaluated for each sample. Not enough evidence (p > 0.05) was found indicating the hot water wash intervention reduced bacterial concentration on the carcass surface. E. coli was below detection limits (<0.25 CFU/cm2) in most of the samples taken. No significant difference (p > 0.05) was found between coliform counts throughout the sampling dates. Feed type did not seem to influence the (p > 0.25) microbial load of the treatments. Even though no immediate effect was seen when comparing spray or dry chilling of the samples at day 0, as the product aged, a significantly lower (p < 0.05) concentration of aerobic and psychrotrophic organisms in dry-chilled samples could be observed when compared to their spray-chilled counterparts. Data collected can be used to select alternative chilling systems to maximize shelf life in vacuum packaged beef kept over prolonged storage periods.


2021 ◽  
Author(s):  
Jainy Mavani

Recreational water users may be exposed to elevated pathogen levels that originate from various point and non-point sources. Current daily notifications practice depends on microbial analysis of indicator organisms such as Escherichia coli (E. coli) that require 18-24 hours to provide sufficient response. This research evaluated the use of Artificial Neural Networks (ANNs) for real time prediction of E. coli concentration in water at Toronto beaches (Ontario, Canada). The nowcasting models were developed in combination with readily available real-time environmental and hydro-meteorological data during the bathing season (June-August) of 2008 to 2012. The results of the developed ANN models were compared with historic data and found that the predictions of E. coli concentrations generated by ANN models slightly outperforms than currently used persistence model with better accuracy. The best performing ANN models for each beach are able to predict approximately 74% to 82% of the E. coli concentrations.


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