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Assembly of 6-aza-2-thiothymine on gold nanoparticles for selective and sensitive colorimetric detection of pencycuron in water and food samples Полный текст
2019
Kailasa, Suresh Kumar | Nguyen, Thang Phan | Baek, Seung Hoon | Tu Phan, Le Minh | Rafique, Rafia | Park, Tae Jung
A facile and novel nanosensor analytical strategy was developed for the colorimetric detection of pencycuron fungicide in rice, potato, cabbage, and water samples based on the pencycuron-induced aggregation of 6-aza-2-thiothymine-functionalized gold nanoparticles (ATT-AuNPs). The ATT-AuNPs exhibited good stability and were characterized with UV-visible spectroscopy, Fourier transform infrared (FT-IR) spectrometry, field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential techniques. The addition of pencycuron facilitated strong non-covalent interactions (electrostatic, van der Waals, and H bonding) between pencycuron and ATT-AuNPs, inducing a significant red shift in the surface plasmon resonance (SPR) peak of ATT-AuNPs along with a color change from red to blue. A linear equation was established between absorption ratio (A720/A528) and pencycuron concentration (2.5–100 μM) with a correlation coefficient (R2) of 0.9915. The detection limit was calculated to be 0.42 μM, which was much lower than that of other analytical methods. The designed ATT-AuNP serves as a promising nanosensor for the rapid, simple, and selective label-free colorimetric detection of pencycuron in rice, potato, cabbage, and water samples, is highly sensitive, and does not require sophisticated instruments, tedious sample preparations, and time-consuming separation and pre-concentration procedures.
Показать больше [+] Меньше [-]The oxidative stability of omega-3 oil-in-water nanoemulsion systems suitable for functional food enrichment: A systematic review of the literature Полный текст
2019
Bush, Linda | Stevenson, Leo | Lane, Katie E.
There is growing demand for functional food products enriched with long chain omega-3 polyunsaturated fatty acids (LCω3PUFA). Nanoemulsions, systems with extremely small droplet sizes have been shown to increase LCω3PUFA bioavailability. However, nanoemulsion creation and processing methods may impact on the oxidative stability of these systems. The present systematic review collates information from studies that evaluated the oxidative stability of LCω3PUFA nanoemulsions suitable for use in functional foods. The systematic search identified seventeen articles published during the last 10 years. Researchers used a range of surfactants and antioxidants to create systems which were evaluated from 7 to 100 days of storage. Nanoemulsions were created using synthetic and natural emulsifiers, with natural sources offering equivalent or increased oxidative stability compared to synthetic sources, which is useful as consumers are demanding natural, cleaner label food products. Equivalent vegetarian sources of LCω3PUFA found in fish oils such as algal oils are promising as they provide direct sources without the need for conversion in the human metabolic pathway. Quillaja saponin is a promising natural emulsifier that can produce nanoemulsion systems with equivalent/increased oxidative stability in comparison to other emulsifiers. Further studies to evaluate the oxidative stability of quillaja saponin nanoemulsions combined with algal sources of LCω3PUFA are warranted.
Показать больше [+] Меньше [-]The application of slightly acidic electrolyzed water in pea sprout production to ensure food safety, biological and nutritional quality of the sprout Полный текст
2019
Zhang, Chunling | Zhang, Yuyu | Zhao, Zhiyi | Liu, Wenfei | Chen, Yiqing | Yang, Gaoji | Xia, Xiaodong | Cao, Yanfei
Slightly acidic electrolyzed water (SAEW) with available chlorine concentrations (ACC) of 35 and 70 mg/L is used instead of regular production water for soaking pea (Pisum sativum L.) seeds and spraying the sprouts during seed sprouting. Sodium hypochlorite (NaOCl) with the same ACC and tap water are used as a control in this study. The population of total bacteria, coliform, yeast and mold are determined at day 2, day 5, day 8, and day 11, respectively during seed sprouting. The biological indicators, nutritive indicators, and nitrite content after the sprouts are harvested are measured as well. The results indicate that when treated with SAEW, the counts of total bacteria, coliform, yeast and mold are reduced by 0.99–1.58 log CFU/g, 0.57–1.02 log CFU/g, and 1.01–1.22 log CFU/g respectively, compared to tap water treatment. Fresh weight, length, and edible rate of the sprouts significantly improve when treated with SAEW (p < 0.05). No evident adverse effects are observed in the nutritive indicators after SAEW treatment. In fact, a slight improvement (soluble sugar, flavonoid) was evident. Moreover, after a storage period of 7 d, the nitrite content of the sprouts was significantly lower in the SAEW treated samples than in any of other treatments. Therefore, SAEW could be a promising application in the production of pea sprouts to ultimately improve food safety.
Показать больше [+] Меньше [-]Research on Total Factor Productivity and Influential Factors of the Regional Water–Energy–Food Nexus: A Case Study on Inner Mongolia, China Полный текст
2019
Junfei Chen | Tonghui Ding | Huimin Wang | Xiaoya Yu
With the supply of water, energy and food facing severe challenges, there has been an increased recognition of the importance of studying the regional water&ndash:energy&ndash:food nexus. In this paper, Inner Mongolia, including 12 cities in China, was selected as a research case. A super-efficiency slack based measure (SBM) model that considered the undesirable outputs was adopted to calculate the regional total factor productivity (TFP) and the Malmquist&ndash:Luenberger index was used to investigate the change trend of the TFP from 2007 to 2016 based on understanding the water&ndash:energy&ndash:food nexus. Finally, influential factors of the TFP were explored by Tobit regression. The results show that the 12 Inner Mongolia cities are divided into higher, moderate and lower efficiency zones. The higher efficiency zone includes Ordos, Hohhot, Xing&rsquo:an, and Tongliao, and the lower efficiency zone includes Chifeng, Xilin Gol, Baynnur, Wuhai and Alxa. There is a serious difference in TFP between Inner Mongolia cities. During the study period, the TFP of the water&ndash:energy&ndash:food nexus in Inner Mongolia cities shows a rising trend, which is mainly driven by the growth of technical progress change. However, the average ML values of the lower and moderate efficiency zones were inferior to the higher efficiency zone in six of the ten years, so the difference between Inner Mongolia cities is growing. According to the Tobit regression, the mechanization level and degree of opening up have positive effects on the TFP, while enterprise scale and the output of the third industry have negative effects on the TFP. Government support does not have any significant impact on the TFP. Finally, suggestions were put forward to improve the TFP of the water&ndash:energy&ndash:food nexus in Inner Mongolia cities.
Показать больше [+] Меньше [-]Estimation of Energy Intake by a Food Frequency Questionnaire: Calibration and Validation with the Doubly Labeled Water Method in Japanese Older People Полный текст
2019
Watanabe, Daiki | Nanri, Hinako | Sagayama, Hiroyuki | Yoshida, Tsukasa | Itoi, Aya | Yamaguchi, Miwa | Yokoyama, Keiichi | Watanabe, Yuya | Goto, Chiho | Ebine, Naoyuki | Higaki, Yasuki | Ishikawa-Takata, Kazuko | Kimura, Misaka | Yamada, Yosuke | Kyoto-Kameoka Study Group,
Accurate assessments of a target population’s energy intake (EI) are essential to prevent poor nutritional status. However, self-reported dietary records (DRs) or food frequency questionnaires (FFQs) are not always accurate, thereby requiring validation and calibration studies. This study aimed to validate the EI estimated by a FFQ using the doubly labeled water (DLW) method. Participants were 109 Japanese older adults (50 women and 59 men) aged 65–88 years. The EI was obtained by a DR and 47-item FFQ over 1 year. The total energy expenditure (TEE) was measured by DLW for ~2 weeks. EI was significantly lower than TEE (p < 0.01); ratios of EI assessed by DR and FFQ against TEE were 0.91 ± 0.17 and 0.82 ± 0.22, respectively. TEE was significantly and moderately correlated with the EI estimated by the DR (r = 0.45, p < 0.01) and FFQ (r = 0.37, p < 0.01). Furthermore, the EI correlation coefficients estimated by DR and the FFQ in this study were not significantly different (p = 0.46). The EI/TEE ratio was significantly and negatively correlated with the body mass index (BMI). In conclusion, EI estimated with a DR or FFQ modestly correlated with TEE, and calibrating EI with a developed equation in this study can attenuate the underestimation of EI.
Показать больше [+] Меньше [-]Health risk assessment on N-nitrosodimethylamine in drinking water and food in major cities of China with disability-adjusted life years (DALYs) Полный текст
2019
Sang, Chenhui | An, Wei | Han, Mingyi | Yang, Min
In this study, a health risk assessment of N-nitrosodimethylamine (NDMA) in drinking water and food was conducted using disability-adjusted life years (DALYs) in major cities of China. Considering the numerous non-detected values found in drinking water samples, a zero-inflated model was employed to obtain a more precise NDMA concentration distribution function in drinking water. With exogenous chronic daily intake of 1.20 × 10⁻⁶ mg/(kg*d), the lifetime cancer risk and disability-adjusted life years of NDMA are 4.01 × 10⁻⁵ and 5.52 × 10⁻⁶ per person-year (ppy). The disease burden attributable to water sources accounts for nearly 9.94% of total exogenous intake. The contribution rate of vegetables is the largest, followed by cereals, milk products, fish and shrimp, and meat. Taking endogenous sources into consideration, the contribution rates of drinking water and food sources decrease to 0.08% and 0.69%. This study provides a scientific basis for making policy decisions on NDMA pollution management.
Показать больше [+] Меньше [-]Analysis of Greenhouse Gas Emissions in Centralized and Decentralized Water Reclamation with Resource Recovery Strategies in Leh Town, Ladakh, India, and Potential for Their Reduction in Context of the Water–Energy–Food Nexus Полный текст
2019
Mounia Lahmouri | Jörg E. Drewes | Daphne Gondhalekar
With the constant increase of population and urbanization worldwide, stress on water, energy, and food resources is growing. Climate change constitutes a source of vulnerability, raising the importance of implementing actions to mitigate it. Within this, the water and wastewater sector represents an important source of greenhouse gas (GHG) emissions, during both the construction and operation phase. The scope of this study is to analyze the GHG emissions from the current and future water supply scheme, as well as to draw a comparison between possible water reclamation with resource recovery scenarios in the town Leh in India: a centralized scheme, a partly centralized combined with a decentralized scheme, and a household level approach. Precise values of emission factors, based on the IPCC Guidelines for National Greenhouse Gas Inventories, previous studies, and Ecoinvent database, have been adopted to quantify the different emissions. Potential sources of reduction of GHG emissions through sludge and biogas utilization have been identified and quantified to seize their ability to mitigate the carbon footprint of the water and wastewater sector. The results show that the future water supply scheme will lead to a significant increase of the GHG emissions during its operation. Further, it is shown that decentralizing wastewater management in Leh town has the least carbon footprint during both construction and operation phases. These results have implications for cities worldwide.
Показать больше [+] Меньше [-]Bacterial protein for food and feed generated via renewable energy and direct air capture of CO2: Can it reduce land and water use? Полный текст
2019
Sillman, Jani | Nygren, Lauri | Kahiluoto, Helena | Ruuskanen, Vesa | Tamminen, Anu | Bajamundi, Cyril | Nappa, Marja | Wuokko, Mikko | Lindh, Tuomo | Vainikka, Pasi | Pitkänen, Juha-Pekka | Ahola, Jero
The global food demand is projected to significantly increase. To maintain global food security in the future, protein production needs to become more efficient regarding the use of limited land and water resources. Protein-rich biomass can be produced via direct air capture of CO2 with the help of H2-oxidizing bacteria and renewable electricity in a closed, climate-independent system. This quantitative literature review conservatively estimated the direct land and water use of bacterial protein production relying on secondary data for the components of the technology and for the reference protein sources. A several times higher potential protein yield per land area can be achieved by this technology with approximately one-tenth of the water use compared to that required for soybean production.
Показать больше [+] Меньше [-]Influência da luz polarizada e da turbidez da água nas taxas de alimentação de paralarvas de Octopus vulgaris tipo II & NBSP Полный текст
2019
Gavioli, Ivan Luiz, 1986- | Vidal, Érica Alves González | Universidade Federal do Paraná. Campus Pontal do Paraná - Centro de Estudos do Mar. Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos
Orientadora: Profa. Dra. Erica Alves Gonzalez Vidal | Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Centro de Estudos do Mar, Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos. Defesa : Pontal do Paraná, 28/03/2019 | Inclui referências | Resumo: O cultivo integral de polvos que produzem ovos pequenos tem como principal obstáculo as altas taxas de mortalidade e o baixo crescimento durante a fase de paralarva. Como as paralarvas de Octopus vulgaris são predadores visuais que demandam presa viva, hipotetizou-se que manipulando condições ambientais relacionadas à luz, as taxas de alimentação (TA) poderiam melhorar. Portanto, o objetivo deste estudo é avaliar se luz polarizada ou turbidez da água aumentam as TA de paralarvas de O. vulgaris recém eclodidas quando alimentadas com presa natural (copépode, Acartia lilljeborgi), bem como quantificar as TA e estimar o consumo energético diário (CED) das paralarvas. Uma paralarva recém-eclodida e 40 copépodes foram colocados em cada unidade experimental opaca (0.5 L, 9 cm de diâmetro, 13 cm de altura) contendo aeração suave por 24 h. Cinco réplicas foram utilizadas em cada experimento, junto com três controles. Estes continham apenas presas e foram utilizados para avaliar mortalidade natural e erros metodológicos tanto da manutenção quanto da quantificação das presas. O experimento de luz polarizada teve um Tratamento Controle (sem luz polarizada) e dois Tratamentos sob luz polarizada (com vetores eletrônicos a 90º e a 45º). O experimento de turbidez da água teve um Tratamento Controle (sem microalgas) e três outros Tratamentos com distintas densidades de Isochrysis galbana (5, 25 e 55 x104 cel. mL-1). As TA diária das paralarvas foram quantificadas pela média obtida das diferenças entre o número de copépodes colocados no início do experimento e a quantidade de copépodes que sobraram em cada unidade experimental ao final do experimento. Uma TA geral foi estabelecida através da média da TA obtida em todos os tratamentos sem diferença significativa. O CED foi estimado através da multiplicação da TA observada pelo conteúdo energético individual dos copépodes. Não foram encontradas diferenças significativas nas taxas de alimentação nos experimentos de luz polarizada (p-valor 0.562) e de turbidez da água (p-valor 0.428). A variabilidade individual foi elevada com TA mínimas e máximas entre 1 a 10 copépodes paralarva-1 dia-1 (luz polarizada) e de 0 a 7 copépodes paralarva-1 dia-1 (turbidez da água). A taxa de alimentação geral foi de 3.86 ± 2.26 copépodes paralarva-1 dia-1 e o CED médio foi de 0.135 cal. paralarva- 1 dia-1. Este CED representa 99% da taxa metabólica de uma paralarva em repouso ou 18% de uma paralarva ativa. O que pode indicarque o metabolismo das paralarvas recém eclodidas depende principalmente da reserva vitelínica. Algumas hipóteses para explicar a falta de correlação entre TA e luz polarizada ou turbidez da água são apresentadas e discutidas. O valor de TA obtido usando presas naturais é um dado confiável e importante sobre as demandas diárias alimentares de paralarvas de Octopus em ambiente de cultivo. Esta informação será de grande valor para o estabelecimento de um protocolo alimentar para paralarvas desta espécie. | Abstract: The large scale culture of Octopuses that produce small eggs are mainly hindered by the high mortality and poor growth during the paralarval phase. Since Octopus vulgaris paralarvae are visual predators that requires live prey, we hypothesized that manipulating environmental conditions related to light could improve paralarvae feeding rates (FR). Therefore, the aim of this study is to evaluate if polarized light (PL) or water turbidity (WT) enhance newly-hatched O. vulgaris Type II paralarvae FR when fed on natural prey (copepods, Acartia lilljeborgi), as well as quantify their FR and estimate their daily energy consumption (DEC). Newly-hatched paralarva was placed together with 40 copepods into opaque black experimental units (0.5 L, 9 cm diameter, 13 cm height) with gently aeration for 24 h. Five replicate units were used for each treatment. Three Control replicates without paralarvae, but containing the prey, were used to evaluate natural mortality and methodological errors in prey maintenance and quantification. The PL experiment had a Control Treatment (no polarized light) and two under polarized light Treatments (the electronic vector at 90º and at 45º). The WT experiment had a Control Treatment (no algae) and three other Treatments with Isochrysis galbana indifferent densities (5, 25 and 55 x104 cellsmL-1). Daily FR of paralarvae were quantified by the subtraction of the number of remaining copepods after the end of the experiment from the total number placed into each experimental unit. A general FR was established considering all non-significantly different treatments. DEC was estimated by multiplying the FR by the copepods individual energetic content. No significant differences on the FR were found for PL (p-value 0.562) and for WT (p-value 0.428). Individual variability was high with minimal and maximum FR ranging from 1to 10 copepods paralarva-1day-1, on the PL experiment and from 0 to 7 copepods paralarva- 1day-1 on the WT experiment. The general FR was 3.86 ± 2.26 copepods paralarva-1day-1 and average DEC was 0.135 cal. paralarva-1day-1. The DEC value represented both 99% of metabolic rate (MR) of resting paralarvae and 18% of MR of active paralarvae. This could suggest that if the MR model used is not overestimated that paralarvae metabolism rely mainly on the yolk reserve. A range of hypotheses - from the sample size to the polarized vision development being dependent on stimuli and experience - are presented and discussed to explain the lack of correlation between FR and LP or WT. The FR values obtained using natural prey provide reliable and important data on the daily feeding requirements of Octopus paralarvae under culture conditions. This information will have special value in establishing a feeding protocol for rearing paralarvae.
Показать больше [+] Меньше [-]Effect of Food Structure, Water Activity, and Long-Term Storage on X-Ray Irradiation for Inactivating Salmonella Enteritidis PT30 in Low-Moisture Foods Полный текст
2019
Steinburnner, Philip J. | Limcharoenchat, Pichamon | Suehr, Quincy J. | Ryser, Elliot T. | Marks, Bradley P. | Jeong, Sanghyup
Recent outbreaks and recalls of low-moisture foods contaminated with Salmonella have been recognized as a major public health risk that demands the development of new Salmonella mitigation strategies and technologies. This study aimed to assess the efficacy of X-ray irradiation for inactivating Salmonella on or in almonds (kernels, meal, butter), dates (whole fruit, paste), and wheat (kernels, flour) at various water activities (aw) and storage periods. The raw materials were inoculated with Salmonella Enteritidis PT30, conditioned to 0.25, 0.45, and 0.65 aw in a humidity-controlled chamber, processed to various fabricated products, and reconditioned to the desired aw before treatment. In a storage study, inoculated almond kernels were stored in sealed tin cans for 7, 15, 27, and 103 weeks, irradiated with X ray (0.5 to 11 kGy, targeting up to a ∼2.5-log reduction) at the end of each storage period, and plated for Salmonella survivors to determine the efficacy of irradiation in terms of D10-value (dose required to reduce 90% of the population). Salmonella was least resistant (D10-value = 0.378 kGy) on the surface of almond kernels at 0.25 aw and most resistant (D10-value = 2.34 kGy) on the surface of dates at 0.45 aw. The Salmonella D10-value was 61% lower in date paste than on whole date fruit. Storage of almonds generally had no effect on the irradiation resistance of Salmonella over 103 weeks. Overall, these results indicate that product structure (whole, meals, powder, or paste), water activity (0.25 to 0.65 aw), and storage period (0 to 103 weeks) should be considered when determining the efficacy of X-ray irradiation for inactivating Salmonella in various low-water-activity foods.
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