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[学术文献 ] Cloning of Camellia sinensis MLO1 gene and analysis of disease resistance of miRNA as green pesticide 进入全文
Plant Cell, Tissue and Organ Culture 期刊
Tea plants (Camellia sinensis (L.) O. Ktze), a key economic crop in China, are severely impacted by diseases, significantly reducing tea production. Due to issues such as resistance and pesticide residues associated with traditional chemical control, developing green control methods is crucial. The Mildew Resistance Locus O (MLO) gene, a negative regulator of plant disease resistance, has been a focal point in plant disease resistance research for years. This study identified 28 CsMLO gene family members in the tea plant genome and selected the CsMLO1 gene, which exhibits significant expression changes under pathogen stress, for cloning and functional validation. The virus-induced gene silencing (VIGS) assay revealed that silencing CsMLO1 in tea plants significantly enhances their disease resistance. Further overexpression of the CsMLO1 gene in tobacco and subsequent infection with powdery mildew revealed a significant decrease in resistance upon overexpression. These results suggest that CsMLO1 negatively regulates plant disease resistance. Through database comparison analysis, we screened out the miRNA interacting with the CsMLO1 gene, namely novel-miRNA-76-5p. To investigate its function, we subjected the sprayed plants to pathogen stress experiments. The findings from the analysis indicated that the activities of various protective enzymes in tea leaves treated with novel miRNA-76-5p were significantly increased, the area of disease spots was significantly reduced, and the plant stress resistance was significantly enhanced. The experiments demonstrated that miRNA exhibits a significant control effect against fungal diseases in tea plants, offering a novel research direction for the eco-friendly management of tea plant diseases.
[会议论文 ] In Vitro Antioxidant Effect of Insect Tea Polyphenols 进入全文
ISAFB 2019 会议
Insect tea is a traditional beverage in China. In this study, the Insect tea polyphenols were extracted and the in vitro antioxidant effects of Insect tea polyphenols were preliminarily studied. It was found that the content of polyphenols in Insect tea polyphenols extracted by ion precipitation reached 71.2%. In further experiments, the DPPH, ABTS and hydroxyl radical scavenging capacities of Insect tea polyphenols were increased with the higher concentrations of Insect tea polyphenols. When the concentration reached 1 mg/mL, the DPPH, ABTS and hydroxyl radical scavenging capacities of Insect tea polyphenols reached 84.9%, 62.1% and 47.8%, respectively. It can be seen that the Insect tea polyphenols have good antioxidant effect in vitro and they are a kind of bioactive substances worth exploiting and utilizing.
[学术文献 ] Residue pattern and risk assessment of validamycin A and spinosyn A in tea using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry 进入全文
Food Chemistry 期刊
Validamycin A (VA) and spinosyn A (SA) have been utilized as antibiotic pesticides in tea plantations for the control of pests and diseases. Both pesticides pose significant risks to human health and have been listed as key controlled new pollutants in China. So far, there have been few reports for the risk assessment of antibiotic pesticides in tea. In this study, a hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS) method was developed for the simultaneous detection of VA and SA residues in tea. Method validation demonstrated good accuracy and precision. During tea planting, SA and VA in tea shoots degraded fast, with the half-life of 0.36 to 0.43 days for SA and 0.72 to 0.92 days for VA. SA and VA in tea shoots degraded fast initially and then followed by a slower phase. Both SA and VA degraded rapidly during the withering and drying stages. Compared to green tea, the degradation rates of both pesticides were faster during black tea manufacturing. Transfer rates of VA and SA from tea into infusions had transfer rates of 76.7 % to 99.5 % and 1.5 % to 2.7 %, respectively. The chronic risk quotient (RQc) < 1 for both antibiotic pesticides indicated negligible consumer risk from tea.
[前沿资讯 ] 2025 UK Tea and Infusions Census Study Reveals How Brits Take Tea 进入全文
World Tea News 网站
UK Tea and Infusions Association（UKTIA）委托对1000多名英国人进行的最新真实世界新茶普查研究显示，红茶是英国人最受欢迎的茶。研究发现：71%的英国人更喜欢传统的红茶，加牛奶或不加牛奶；16%的英国人更有可能选择花草茶；13%的英国人主要选择绿茶。UKTIA的茶叶普查研究还发现，年龄在人们对茶的偏好中起着重要作用：在18-24岁的人群中，63%的人表示他们主要喝红茶；在18至24岁的人群中，有20%的人正在尝试各种花草茶或绿茶；65岁以上人群中，86%的人主要喝红茶；在65岁以上的人群中，只有不到十分之一的人喝花草茶或绿茶；研究还发现了性别之间的差异：19%的女性选择花草茶，而男性只有12%。在所有年龄组中，绝大多数人（93%）更喜欢用茶包泡茶，而不是用散叶泡茶。
[学术文献 ] Kinetics, pathways, mechanism and toxicity evaluation of chiral pesticide Paichongding during the fermentation of Puer tea 进入全文
Food Chemistry: X 期刊
The presence of pesticide residues in tea has garnered increasing scholarly attention. Following the withdrawal of highly toxic pesticides from the market, there is a pressing need for alternative solutions to mitigate pest and disease occurrences in tea plantations. This study focuses on the neonicotinoid chiral pesticide of Paichongding(IPP), which possesses two chiral centers and four distinct isomers. We investigated the selective degradation of Paichongding isomers during the fermentation of Puer tea, tracking intermediate metabolites throughout the process. Using Density Functional Theory (DFT), we estimated the potential active sites of Paichongding and evaluated the toxicity of its intermediate products. Our findings indicate that Paichongding undergoes diastereo-selective degradation during Puer tea fermentation, resulting in the identification of seven key intermediates. Computational analysis revealed that the primary reaction sites of Paichongding are located on the imidazole and tetrahydropyridine rings. Toxicity assessments demonstrated that the metabolites exhibited heightened toxicity towards human genetic material, respiratory functions, and small aquatic organisms.
[学术文献 ] QBIC-based terahertz metasurface used for the detection of chlorpyrifos in tea 进入全文
Photonics Research 期刊
Pesticide residues in tea are an important problem affecting the sustainable development of the tea industry; thus, pesticide detection is the key to ensuring the quality and safety of tea. Here, a terahertz metasurface structure based on the quasi-bound state in the continuum is proposed, which consists of two copper microrods arranged periodically. This design in the metasurface provides strong local enhancement near the surface of the microstructure, significantly improving the interaction of light with the analyte, resulting in increased sensitivity. The simulated and experimental results show that the metasurface structure can be used to detect the refractive index of trace analytes with a high sensitivity and successfully detect low concentrations of chlorpyrifos in tea. This study provides a new idea for the detection of pesticide residues in tea.
