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Water and food quality
1989
Hardman, T.M. (ed.)
Fluoroquinolone pollution of food, water and soil, and bacterial resistance Texto completo
2015
Rusu, Aura | Hancu, Gabriel | Uivaroşi, Valentina
Fluoroquinolones are a valuable synthetic antibacterial class widely used in the treatment of infectious diseases both in humans and animals. Until recently, it has been thought that bacterial resistance to fluoroquinolones develops very slowly. Nowadays, there are multiple studies that reveal the alarming occurrence of bacterial resistance and there is a high risk of becoming therapeutically useless. The emergence of this phenomenon comes from injudicious usage in therapy, the presence of residues and their metabolites in food of animal origin and also in sewage, compost and domestic waste, which end up in soil and water sources. In the present paper, we reviewed important issues regarding fluoroquinolones impact on the environment in connection with the development of bacterial resistance: (1) the presence of fluoroquinolones as pollutants in soil, surface waters, and food. Fluoroquinolones are persistent with high specificity to interact with soil compared to other antibiotics. Pollution of water sources raises concerns regarding the effects of small concentrations (ng L⁻¹) on human health and also of the environment. The non-therapeutic use in animal farms conducts to food pollution; the cultivated plants could concentrate the fluoroquinolones (over 100 μg L⁻¹); (2) the increase of bacterial resistance to fluoroquinolones occurring with specific mutations in the target enzymes as well by the plasmid-mediated resistance and active efflux of the cell; (3) international regulations of the fluoroquinolone residues in food that are far to encompass all compounds; (4) fluoroquinolones residues analysis with standardized methods should provide limits of detection lower than maximum residue limit values; and (5) trends and perspectives: (a) a wider process of harmonization of regulations; (b) the fluoroquinolones restriction, necessary for low levels of bacterial resistance; (c) the soil and waste water purification methods; (d) the practice of soil planting scheme as an alternative; and (e) an environmental label in order to facilitate the selection of drugs.
Mostrar más [+] Menos [-]Toxic and recovery effects of copper on Caenorhabditiselegans by various food-borne and water-borne pathways Texto completo
2012
Yu, Zhen-Yang | Zhang, Jing | Yin, Da-Qiang
Copper pollutions are typical heavy metal contaminations, and their ability to move up food chains urges comprehensive studies on their effects through various pathways. Currently, four exposure pathways were prescribed as food-borne (FB), water-borne plus clean food (WCB), water–food-borne (WFB) and water-borne (WB). Caenorhabditiselegans was chosen as the model organism, and growth statuses, feeding abilities, the amounts of four antioxidant enzymes, and corresponding recovery effects under non-toxic conditions with food and without food were investigated. Based on analysis results, copper concentrations in exposure were significantly influenced by the presence of food and its uptake by C.elegans. Both exposure and recovery effects depended on exposure concentrations and food conditions. For exposure pathways with food, feeding abilities and growth statuses were generally WFB<WCB⩽FB (p<0.05). The antioxidant activities were up-regulated in the same order. Meanwhile, the exposure pathway without food (WB) caused non-up-regulated antioxidant activities, and had the best growth statuses. For recoveries with food, growth statuses, feeding abilities and the inductions of the antioxidant enzymes were all WB≈WFB<WCB<FB (p<0.05). For recoveries without food, the order of growth statuses remained WB>FB>WCB>WFB (p<0.05), while the antioxidant activities were all inhibited in a concentration–dependent fashion. In conclusion, contaminated food was the primary exposure pathway, and various pathways caused different responses of C.elegans.
Mostrar más [+] Menos [-]Enzymatic assays for the assessment of toxic effects of halogenated organic contaminants in water and food. A review Texto completo
2020
Artabe, Amaia Ereño | Cunha-Silva, Hugo | Barranco, Alejandro
Halogenated organic compounds are a particular group of contaminants consisting of a large number of substances, and of great concern due to their persistence in the environment, potential for bioaccumulation and toxicity. Some of these compounds have been classified as persistent organic pollutants (POPs) under The Stockholm Convention and many toxicity assessments have been conducted on them previously. In this work we provide an overview of enzymatic assays used in these studies to establish toxic effects and dose-response relationships. Studies in vivo and in vitro have been considered with a particular emphasis on the impact of halogenated compounds on the activity of relevant enzymes to the humans and the environment. Most information available in the literature focuses on chlorinated compounds, but brominated and fluorinated molecules are also the target of increasing numbers of studies. The enzymes identified can be classified as enzymes: i) the activities of which are affected by the presence of halogenated organic compounds, and ii) those involved in their metabolisation/detoxification resulting in increased activities. In both cases the halogen substituent seems to have an important role in the effects observed. Finally, the use of these enzymes in biosensing tools for monitoring of halogenated compounds is described.
Mostrar más [+] Menos [-]Enzyme (Single and Multiple) and Nanozyme Biosensors: Recent Developments and Their Novel Applications in the Water-Food-Health Nexus Texto completo
2021
Lynette Alvarado-Ramírez | Magdalena Rostro-Alanis | José Rodríguez-Rodríguez | Juan Eduardo Sosa-Hernández | Elda M. Melchor-Martínez | Hafiz M. N. Iqbal | Roberto Parra-Saldívar
The use of sensors in critical areas for human development such as water, food, and health has increased in recent decades. When the sensor uses biological recognition, it is known as a biosensor. Nowadays, the development of biosensors has been increased due to the need for reliable, fast, and sensitive techniques for the detection of multiple analytes. In recent years, with the advancement in nanotechnology within biocatalysis, enzyme-based biosensors have been emerging as reliable, sensitive, and selectively tools. A wide variety of enzyme biosensors has been developed by detecting multiple analytes. In this way, together with technological advances in areas such as biotechnology and materials sciences, different modalities of biosensors have been developed, such as bi-enzymatic biosensors and nanozyme biosensors. Furthermore, the use of more than one enzyme within the same detection system leads to bi-enzymatic biosensors or multi-enzyme sensors. The development and synthesis of new materials with enzyme-like properties have been growing, giving rise to nanozymes, considered a promising tool in the biosensor field due to their multiple advantages. In this review, general views and a comparison describing the advantages and disadvantages of each enzyme-based biosensor modality, their possible trends and the principal reported applications will be presented.
Mostrar más [+] Menos [-]In vitro synthetic enzymatic biosystems at the interface of the food-energy-water nexus: A conceptual framework and recent advances Texto completo
2018
Zhu, Zhiguang | You, Chun | Ma, Yanhe | Zhang, Yi-Heng P Job
The food-energy-water (FEW) nexus is interconnected and interdependent and provides a physical foundation for mankind. The production of safe food, renewable energy, and clean water through biological means, especially microbial bioconversion, has attracted an enormous attention worldwide. Recently, in vitro synthetic enzymatic biosystems (ivSEBs) comprised of numerous enzymes and coenzymes, as a disruptive biomanufacturing platform, has been proposed and demonstrated to address key challenges at the interface of the FEW nexus. Light, electricity, and hydrogen can provide energy to fix CO2 and produce food and biomass. Lignocellulose-derived cellulose can be converted to starch and biofuels. Starch can be further converted to bioenergy, including electricity, hydrogen and liquid fuels. These high-energy efficient bioprocesses lead to significantly less water usage and also can be used to reduce water pollution. In this review, the conceptual framework and latest advances of ivSEBs in the FEW nexus are summarized. Their limitations and future research directions on the design and improvement of ivSEBs are also discussed.
Mostrar más [+] Menos [-]Degradation kinetics of encapsulated grape skin phenolics and micronized grape skins in various water activity environments and criteria to develop wide-ranging and tailor-made food applications Texto completo
2017
Lavelli, Vera | Sri Harsha, Pedapati S.C. | Laureati, Monica | Pagliarini, Ella
Micronized grape skin powder (GS) and maltodextrin-encapsulated grape skin phenolics (eGSP) were recovered from winemaking byproducts as potential food ingredients. Hygroscopicity was higher in eGSP than in GS. Both eGSP and GS had intense color and less fermented odor than the wet GS. Phenolic content, antioxidant activity and inhibitory effectiveness towards enzymes related to hyperglycemia damage were ~ double in eGSP than in GS. During storage, the rate of phenolic degradation diminished with decreasing aw from 0.75 to 0.11. Anthocyanins and proanthocyanidins were less stable than monomeric flavanols and flavonols. The rate of decrease in antioxidant activity was lower compared to the extent of phenolic degradation. At aw 0.11 no degradation was observed in eGSP, while anthocyanin and proanthocyanidin contents slightly decreased in GS (k∗103 in the range 0.69–2.94d−1). Criteria for GS and eGSP storage were defined in relation to their final uses.The conversion of winemaking by products into value added products is considered the unique strategy to overcome the cost of not recycling, including waste disposal and decontamination of affected areas. As winemaking is a seasonal activity, long-term stability of recovered byproducts is needed for their further utilization. GS and eGSP represent potential value-added food ingredients for wide-ranging applications (antioxidant, colorant, phenolic sources) and tailor-made functionalities (inhibitors of enzymes related to hyperglycemia). The results obtained led to the definition of criteria for GS and eGSP storage, which depend on their final use in foods, as illustrated by two discussed scenarios.
Mostrar más [+] Menos [-]Effects of cooling dry cows under heat load conditions on mammary gland enzymatic activity, intake of food and water, and performance during the dry period and after parturition Texto completo
2009
Adin, G. | Gelman, A. | Solomon, R. | Flamenbaum, I. | Nikbachat, M. | Yosef, E. | Zenou, A. | Shamay, A. | Feuermann, Y. | Mabjeesh, S.J. | Miron, J.
Effect of evaporative cooling of pregnant dairy cows under heat load conditions during the dry and close-up period, on mammary gland enzymatic activity and intake of food and water, BCS, and milk performance after calving were measured in two consequent experiments. In experiment 1, 18 dry cows held in tie-stalls in a closed aerated barn under heat load conditions were used to measure the effect of evaporative cooling on the respiratory rate and body temperature, individual intake of food and water, enzymes expression level in mammary gland and adipose tissues, and BCS changes until calving. In experiment 2, two groups of 36 dry cows each, held in a commercial loose housing barn, were used to measure the effects of evaporative cooling under heat load conditions on calves' birth weight, colostrum quality and quantity, BCS changes and milk yield during 90 DIM. The non cooled (NC) cows responded to heat load by increasing their respiratory rate and daily water intake, while elevating their rectal temperature by 0.2-0.3 °C as compared with the cooled (C) cows. The external relief of heat load by the C cows in both experiments was expressed in increasing their voluntary DMI during the dry period as compared with the NC group. In experiment 2 the calves' birth weight of C cows was higher, and their colostrum quality and quantity were improved as compared with the NC group. Cooling also improved significantly BCS gain during the last 21 days until parturition, accompanied with higher cell proliferation process (based on enzymes expression at mRNA level) in the mammary gland of the C cows. Consequently, a significant increase in milk production by 5.3%, protein yield by 5.1%, ECM yield by 4.2% and FCM yield by 4.5%, was demonstrated in the C cows during 90 DIM as compared with the NC group.
Mostrar más [+] Menos [-]Studien uber die Beziehung zwischen Enzymaktivitat und Wassergehalt in lufttrockenen Lebensmitteln sowie in trockenen und flussigen Modellgemischen | Studies on the relation between enzyme activity and water content in air-dried food as well as in dry and liquid model mixtures
0001
Gehlert, Gunter