Development of a Novel UPLC-MS/MS Method for the Simultaneous Determination of 16 Mycotoxins in Different Tea Categories

The contamination of potential mycotoxins in tea production and consumption has always been a concern. However, the risk monitoring on multiple mycotoxins remains a challenge by existing methods due to the high cost and complex operation in tea matrices. This research has developed a simple ultra-performance liquid chromatography-tandem mass spectrometry strategy based on our homemade purification column, which can be applied in the detections of mycotoxins in complex tea matrices with high-effectively purifying and removing pigment capacity for 16 mycotoxins. The limits of detection and the limits of quantification were in the ranges of 0.015~15.00 and 0.03~30.00 µg·kg⁻¹ for 16 mycotoxins, respectively. Recoveries from mycotoxin-fortified tea samples (0.13~1200 µg·kg⁻¹) in different tea matrices ranged from 61.27 to 118.46%, with their relative standard deviations below 20%. Moreover, this method has been successfully applied to the analysis and investigation of the levels of 16 mycotoxins in major categories of tea and the monitoring of multiple mycotoxins in processed samples of ripened Pu-erh. In conclusion, the proposed strategy is simple, effective, time-saving, and low-cost for the determination of a large number of tea samples.     

低氟砖茶预防大鼠砖茶型氟中毒的实验观察

目的 观察低氟砖茶预防砖茶型氟中毒的效果。方法 用低氟砖茶（含氟量210．0mg/kg）和普通砖茶（含氟量503．5mg/kg）制备的茶水喂饲Wistar大鼠,在4,8,12个月时观察动物的日总摄氟量,茶氟在动物体内的代谢情况和氟中毒情况。结果 普通砖茶组动物在0．3mg左右的日总摄氟量时,8个月开始出现以棕、白横纹为主的氟斑牙,12个月后发展为以白垩为主的氟斑牙,患病率达75．0％。低氟砖茶组动物日总摄氟量0．19mg,实验期间未出现氟中毒症状。氟代谢观察表明,半量茶氟通过尿、粪便排出体外,体内吸收的氟绝大部分进入骨骼。结论 低氟砖茶能有效预防砖茶型氟中毒。     

Relationship between plasma total homocysteine level and dietary caffeine and vitamin B6 intakes in pregnant women

A high total homocysteine (tHcy) level during pregnancy is a risk factor for adverse perinatal outcomes, such as fetal growth restriction and preeclampsia. Caffeine is assumed to increase tHcy levels by acting as a vitamin B₆ antagonist. The objective of this study was to examine a relationship between circulating tHcy levels and dietary caffeine and vitamin B₆ intakes in pregnant Japanese women. A total of 321 healthy women with singleton pregnancies were recruited in metropolitan Tokyo, from June to December 2008, resulting in the final number included in the study as 254. Dietary caffeine intakes did not correlate with plasma tHcy levels. When we analyzed the data according to caffeinated beverages, caffeinated tea consumption was positively associated with plasma tHcy levels only among the women with a high intake of vitamin B₆, after controlling for confounding factors (P = 0.029). No correlation between coffee consumption and plasma tHcy levels was found. Pregnant Japanese women might need to cut down the consumption of caffeinated tea as well as take sufficient vitamin B₆ in order to prevent the tHcy levels from increasing.     

Acute and subchronic oral toxicities of Pu-erh black tea extract in Sprague-Dawley rats

Ethnopharmacological relevance

Pu-erh black tea, which is obtained by first parching crude green tea leaves and then undergoes secondary fermentation with microorganisms, has been believed to be beneficial beverages for health for nearly 2000 years in China, Japan and Taiwan area. But its potential toxicity when administered at a high dose as concentrated extracts has not been completely investigated.

The aim of the study

The present study was aimed at evaluating potential toxicity of Pu-erh black tea extracts (BTE) from acute and sub-chronic administration to male and female Sprague-Dawley (SD) rats.

Materials and methods

A single BTE dose of 10,000 mg/kg of body weight was administered by oral gavage for acute toxicity in SD rats. Four groups (10 males and 10 females per group) of dose levels of 1250, 2500, and 5000 mg/kg/day of the test article, as well as controls (distilled water) were tested as the subchronic toxicity study.

Results

No deaths and signs of toxicity occurred during the 14 days of the study. There were no test article related mortalities, body weight gain, feed consumption, clinical observation, organ weight changes, gross finding, clinical or histopathological alterations during the 91-day administration.

Conclusions

The LD₅₀ of BTE can be defined as more than 10,000 mg/kg, and a dose of 5000 mg/kg/day was identified as the no-observed-adverse-effect-level (NOAEL) in this study.     

茶饮与健康

本文通过历史回顾、现实意义和展望将来三个方面来论述茶饮与健康的密切关系。习俗上所称的山茶科山茶属的茶,在唐代被作为主要的茶饮而得到飞速发展,民间经常使用非山茶科的茶则被称为“别样茶”。研究、开发茶和别样茶,对弘扬中华文化,支援西部大开发和发展三农经济以及防治慢性疾患方面具有重要意义。本文除了对茶饮的定义和分类作了阐述外,还提出了今后的展望,并建议有关方面在做健康产业规划时,在顶层设计中应考虑将茶饮的研究和开发作为重要内容。     

Green tea as an adjunctive therapy for treatment of acute uncomplicated cystitis in women: A randomized clinical trial

Backgroundand purpose: Different in vitro studies have reported the antimicrobial effects of green tea catechins and also their synergistic effects with trimethoprim–sulfamethoxazole against E. coli. The aim of the present study was to evaluate the efficacy of green tea as an adjunctive therapy to standard antimicrobial treatment in women with acute uncomplicated cystitis.Materials and methodsIn this blinded randomized trial, 70 patients were assigned to receive four 500 mg capsules of green tea or starch as placebo daily for three days along with trimethoprim–sulfamethoxazole. The presence of acute uncomplicated cystitis symptoms was recorded and urinalysis was performed.ResultsWomen in the green tea group showed a statistically significant decrease in the prevalence of cystitis symptoms and a statistically significant improvement in the urinalysis results except for hematuria after 3 days of treatment.ConclusionGreen tea was an effective adjunct to trimethoprim–sulfamethoxazole to treat acute uncomplicated cystitis in women.     

EGCG stabilizes growth cone filopodia and impairs retinal ganglion cell axon guidance

Background : Antioxidants such as the green tea polyphenol epigallocatechin gallate (EGCG) are neuroprotective under many conditions in mature nervous systems; however, their impact has rarely been explored in developing nervous systems, in which a critical step is the formation of connections between neurons. Axons emerge from newly formed neurons and are led by a dynamic structure found at their tip called a growth cone. Here we explore the impact of EGCG on the development of retinal ganglion cell (RGC) axons, which connect the eye to the brain. Results : EGCG acts directly on RGC axons to increase the number of growth cone filopodia, fingerlike projections that respond to extrinsic signals, in vitro and in vivo. Furthermore, EGCG exposure leads to a dramatic defect in the guided growth of RGC axons where the axons fail to make a key turn in the mid‐diencephalon required to reach their target. Intriguingly, at guidance points where RGCs do not show a change in direction, EGCG has no influence on RGC axon behavior. Conclusions : We propose that EGCG stabilizes filopodia and prevents normal filopodial dynamics required for axons to change their direction of outgrowth at guidance decision points. Developmental Dynamics 245:667–677, 2016. © 2016 Wiley Periodicals, Inc.     

茉莉花、茉莉花茶提取液对部分免疫效应的影响

目的: 观察茉莉花茶提取液和茉莉花提取组分对脾淋巴细胞转化及中性粒细胞增殖活性的影响,为茉莉花茶和茉莉花的应用提供前期研究数据。方法: 采用水提法制作茉莉花茶浸出液,采用石油醚浸泡制备茉莉花脱脑油并进行柱层析分离。采用脾淋巴细胞转化实验与中性粒细胞吞噬实验检测茉莉花茶浸出液的免疫调节效应,另外采用淋巴细胞增殖法(MTT法)测定茉莉花脱脑油和茉莉花提取组分B-Ⅱ的免疫激活作用。结果: (1)茉莉花茶浸出液能明显提高小鼠淋巴细胞转化率,但对中性粒细胞吞噬率无明显影响。(2)MTT证实茉莉花脱脑油和B-Ⅱ能促进小鼠淋巴细胞生长。结论: 茉莉花茶浸出液、茉莉花脱脑油和B-Ⅱ具有一定的免疫促进效应。     

感冒茶治疗风热感冒临床观察

目的探讨感冒茶治疗风热感冒（挟湿型）的临床疗效。方法将2006年3月至2006年9月门诊确诊为风热感冒（挟湿型）患者依据就诊先后时间随机分为2组,对照组40例服用银翘解毒软胶囊;治疗组66例服用感冒茶颗粒,3d后观察疗效。结果临床治疗66例,总有效率达92.59%,明显优于对照组（76.19%）。结论应用感冒茶颗粒治疗风热感冒（挟湿型）具有较理想的效果,值得临床推广应用。