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[前沿资讯 ] Can drinking coffee or tea help prevent head and neck cancer? 进入全文
Eurekalert 网站
在最近对十几项研究数据的分析中，饮用咖啡和茶与患癌症（包括口腔癌和咽喉癌）的风险较低有关。这项研究结果由Wiley在线发表在美国癌症协会的同行评议期刊《CANCER》上。当研究人员汇总了9548名头颈部癌症患者和15783名非癌症对照组的信息时，他们发现，与非咖啡饮用者相比，每天喝4杯以上含咖啡因咖啡的人患癌症的几率总体降低17%，患口腔癌的几率降低30%，患咽喉癌的几率降低22%。喝3-4杯含咖啡因的咖啡可以降低41%患下咽癌（一种位于喉咙底部的癌症）的风险。Huntsman癌症研究所和犹他大学医学院的资深作者Yuan-Chin Amy Lee博士说：“虽然之前有关于咖啡和茶的消费以及降低癌症风险的研究，但这项研究强调了它们对癌症不同亚位点的不同影响，包括观察到即使是不含咖啡因的咖啡也有一些积极影响。”
[学术文献 ] Unveiling the presence of fluoride in commercial tea infusion: Factors influencing its release and its adsorptive elimination by indigenously developed nanoadsorbents 进入全文
Science of The Total Environment 期刊
Drinking tea, which is globally one of the most widely consumed beverages, is a potential source of fluoride toxicity. This research aimed at fluoride estimation in the infusions of commercial black tea and green tea samples, purchased from the local Indian market, systematic evaluation of the factors influencing the fluoride release and the adsorptive removal of fluoride using the indigenously developed nanoadsorbents. All the prepared infusions had fluoride content above the permissible WHO limits. Various factors, which affect the release of fluoride from tea leaves into the infusion include type of water, tea dosage and brewing time. The investigations revealed that, the fluoride content in the black tea infusions was much higher than the green tea infusions. Further, it also depended on the amount of tea leaves used for brewing. The fluoride, present in tea leaves, is released gradually and within just 1 min of brewing, the concentration of fluoride in the infusions was well above the permissible WHO limits. It was also observed that, the dried unprocessed tea leaves, when brewed in water, had high fluoride content. This further confirmed the presence of fluoride in tea infusion, which demands an efficient remediation technique. The developed nanoadsorbents exhibited efficient defluoridation of groundwater, and were therefore tested for their efficiency in defluoridating tea infusions as well. These nanoadsorbents could efficiently eliminate fluoride from both green and black tea infusions, bringing down the fluoride content below the WHO limits, thereby rendering the infusions safe. They exhibited rapid kinetics with high efficiency in adsorbing fluoride from tea infusions. These properties make them potential adsorbents for defluoridating tea infusion, which provides a probable solution to the problem of fluoride toxicity from drinking tea. This is one of the first reports on a technique for eliminating fluoride from tea infusions.
[学术文献 ] Status and Perspective on Green Pesticide Utilizations and Food Security 进入全文
Annual Review of Food Science and Technology 期刊
Pesticides protect crops against pests, and green pesticides are referred to as effective, safe, and eco-friendly pesticides that are sustainably synthesized and manufactured (i.e., green chemistry production). Owing to their high efficacy, safety, and ecological compatibility, green pesticides have become a main direction of global pesticide research and development (R&D). Green pesticides attract attention because of their close association with the quality and safety of agricultural produce. In this review, we briefly define green pesticides and outline their significance, current registration, commercialization, and applications in China, the European Union, and the United States. Subsequently, we engage in an in-depth analysis of the impact of newly launched green pesticides on the environment and ecosystems. Finally, we focus on the potential risks of dietary exposure to green pesticides and the possible hazards of chronic toxicity and carcinogenicity. The status of and perspective on green pesticides can hopefully inspire green pesticide R&D and applications to ensure agricultural production and safeguard human and ecological health.
[学术文献 ] Monitoring green tea fixation quality byintelligent sensors: comparison of imageand spectral information 进入全文
Journal of the Science of Food and Agriculture 期刊
BACKGROUND：Intelligent monitoring of fixation quality is a prerequisite for automated green tea processing. To meet the requirements of intelligent monitoring of fixation quality in large-scale production, fast and non-destructive detection means are urgently needed. Here, smartphone-coupled micro near-infrared spectroscopy and a self-built computer vision system were used to perform rapid detection of the fixation quality in green tea processing lines. RESULTS：Spectral and image information from green tea samples with different fixation degrees were collected at-line by two intelligent monitoring sensors. Competitive adaptive reweighted sampling and correlation analysis were employed to select feature variables from spectral and color information as the target data for modeling, respectively. The developed least squares support vector machine (LS-SVM) model by spectral information and the LS-SVM model by image information achieved the best discriminations of sample fixation degree, with both prediction set accuracies of 100%. Compared to the spectral information, the image information-based support vector regression model performed better in moisture prediction, with a correlation coefficient of prediction of 0.9884 and residual predictive deviation of 6.46. CONCLUSION：The present study provided a rapid and low-cost means of monitoring fixation quality, and also provided theoretical support and technical guidance for the automation of the green tea fixation process.
[学术文献 ] Automated multi-plug filtration cleanup method for analysis of 48 pesticide residues in green tea using liquid chromatography-tandem mass spectrometry 进入全文
Food Control 期刊
An automated multi-plug filtration cleanup (m-PFC) method, based on QuEChERS extraction was developed for the analysis of 48 pesticides in green tea. The carboxyl functionalized multi-walled carbon nanotubes (MWCNTs-COOH) were firstly packed in m-PFC columns and functioned as promising sorbents with better clean-up capability. The different parameters of automated m-PFC equipment and extraction conditions were optimized. The automated method integrated cleanup and filtration (through filter membrane) procedure into a single run before injected to the detection instrument. Comparison to d-SPE and manual m-PFC method, the automated method could handle a batch of samples simultaneously with better purification effect. Acceptable recoveries at three concentration levels from 71% to 114% were obtained (except carbendazim and bifenazate) with relative standard deviations lower than 18%. The proposed automated m-PFC method offered a great compromise between rapidity, convenience and efficiency. It was successfully applied for market monitoring of pesticide residues with robust analyze data.
[科技图书 ] Cancer Chemoprevention and Treatment by Diet Therapy 进入全文
Springerlink 网站
Throughout the past few years, the cancer chemopreventive potencies and treatment effects of a number of natural dietary agents present in different food sources have been evaluated by various experiments. Some of them have progressed to early clinical trials. This volume is a specialized book presenting the research evidence relevant to the use of specific diet therapy in cancer chemoprevention and treatment. We begin with lessons learned from dietary resveratrol as an effective agent with anticancer properties against malignancies, followed examples of flavonoids from fruits and vegetables in the prevention and treatment of cancer. Evidence for the beneficial influence of diet enriched with flax seed oil and green tea on cancer will be reviewed. Soy food intake may enhance the effects on anticancer treatment for breast cancer, whereas lycopene-rich foods may possess chemopreventive efficacy. There are also discussions on the contribution of the cancer preventive effects of the antioxidant-rich foods and Mediterranean diet. In addition, the modulation of proteasome pathways by nutraceuticals is highlighted. Finally, we close the book with a discussion on the attenuation of cell survival signaling by bioactive phytochemicals in the preventionand therapy cancer.
