Pharmacological effects of green tea on the gastrointestinal system

Green tea is rich in polyphenolic compounds, with catechins as its major component. Studies have shown that catechins possess diverse pharmacological properties that include anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-arteriosclerotic and anti-bacterial effects. In the gastrointestinal tract, green tea was found to activate intracellular antioxidants, inhibit procarcinogen formation, suppress angiogenesis and cancer cell proliferation. Studies on the preventive effect of green tea in esophageal cancer have produced inconsistent results; however, inverse relationships of tea consumption with cancers of the stomach and colon have been widely reported. Green tea is effective to prevent dental caries and reduce cholesterols and lipids absorption in the gastrointestinal tract, thus benefits subjects with cardiovascular disorders. As tea catechins are well absorbed in the gastrointestinal tract and they interact synergistically in their disease-modifying actions, thus drinking unfractionated green tea is the most simple and beneficial way to prevent gastrointestinal disorders.     

茶多酚抑制MDA生成及对阿霉素在小鼠肝细胞内蓄积的影响

荧光光度法测定 MDA及阿霉素在小鼠肝细胞内的含量 ;研究茶多酚抑制 MDA的生成与阿霉素胞内蓄积的关系。结果表明 ,茶多酚浓度为 1 0 ,2 0 ,40 ,80 ,1 60 mg/L时对 MDA生成的抑制率分别为 44.87% ,1 1 5.1 7% ,1 77.2 5% ,1 81 .98% ,1 82 .37% ,且与剂量成正相关。在·OH诱导下 ,茶多酚浓度为 40 mg/L时 ,可明显增加阿霉素在小鼠肝组织细胞内的蓄积     

植物多酚类成分提取分离研究进展

植物多酚是一种广泛存在于植物体内的多元酚类次生代谢产物,随着多酚类成分在抗氧化、抗菌、抗病毒、抗微生物、调血脂和血糖等多方面活性的发现和阐明,植物多酚成为当前研究的热点之一.多酚类成分由于其结构上的复杂性和不稳定性,目前在提取分离上还存在一定的困难.对中药中多酚类成分的提取分离方法进行总结,旨在为下一步分离纯化多酚类成分提供比较系统的信息依据.     

Green Tea Extract Containing Piper retrofractum Fruit Ameliorates DSS-Induced Colitis via Modulating MicroRNA-21 Expression and NF-κB Activity

The aim of the present study was to examine the effect of green tea extract containing Piper retrofractum fruit (GTP) on dextran-sulfate-sodium (DSS)-induced colitis, the regulatory mechanisms of microRNA (miR)-21, and the nuclear factor-κB (NF-κB) pathway. Different doses of GTP (50, 100, and 200 mg/kg) were administered orally once daily for 14 days, followed by GTP with 3% DSS for 7 days. Compared with the DSS-treated control, GTP administration alleviated clinical symptoms, including the disease activity index (DAI), colon shortening, and the degree of histological damage. Moreover, GTP suppressed miR-21 expression and NF-κB activity in colon tissue of DSS-induced colitis mice. The mRNA levels of inflammatory mediators, such as tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin-1β (IL-1β), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), were downregulated by GTP. Colonic nitric oxide (NO) and prostaglandin E2 (PGE2) production, and myeloperoxidase (MPO) activity were also lowered by GTP. Taken together, our results revealed that GTP inhibits DSS-induced colonic inflammation by suppressing miR-21 expression and NF-κB activity, suggesting that it may be used as a potential functional material for improving colitis.     

流感茶的薄层色谱鉴别

目的建立流感茶的质量标准。方法采用薄层色谱法对处方中厚朴、槟榔、广藿香进行定性鉴别。结果薄层色谱中检出厚朴、槟榔、广藿香。结论本方法可行，重现性好，适用于该制剂的质量控制。     

Valorization of Grape Pomace and Berries as a New and Sustainable Dietary Supplement: Development,Characterization, and Antioxidant Activity Testing

Grape pomace and berries represent natural sources of phytochemicals that can increase the quality of life of consumers by contributing to the prevention of chronic diseases; thus, the development of a dietary supplement was necessary. The raw material (r.m.) used for the development of the dietary supplement consisted of dried and powdered bilberries (Vaccinium myrtillus L.), red currants (Ribes rubrum L.), and red fermented pomaces (Vitis vinifera L.) from Feteasca Neagra and Cabernet Sauvignon cultivars. The particle size distribution, powder flow, total phenolic content (TPC), HPLC-DAD phenolic profile assessment, and radical scavenging assay (RSA) were employed for the analysis of the raw material. After encapsulation, the average mass and uniformity of mass, the disintegration, and the uniformity of content for the obtained capsules were performed to obtain a high-quality dietary supplement. All the assays performed complied to the compendial requirements and the TPC was determined at 9.07 ± 0.25 mg gallic acid equivalents/g r.m. and RSA at 48.32 ± 0.74%. The highest quantities of phenolic compounds determined were 333.7 ± 0.50 µg/g r.m. for chlorogenic acid, followed by rutin, ferulic acid, and (+)-catechin with 198.9 ± 1.60 µg/g r.m., 179.8 ± 0.90 µg/g r.m. and 118.7 ± 0.75 µg/g r.m., respectively. The results of this study can be used for the manufacturing and assessing of pilot scale-up capsule batches and thinking of quality assurance, we recommend that the industrial batch extracts should be standardized in polyphenols, and the manufacturing process should be validated.     

老年睑板腺功能障碍蠕形螨感染率及茶树精油联合氟米龙的疗效

目的：研究老年睑板腺功能障碍(MGD)蠕形螨感染率及茶树精油联合氟米龙的疗效。

方法：回顾性病例对照研究。选择2017-09/2018-03在宁波市眼科医院门诊就诊的老年MGD患者59例118眼。将睫毛蠕形螨镜检为阳性的38例患者76眼进行症状评分、蠕形螨数量、泪膜破裂时间(BUT)、角膜荧光素染色(FL)、Schirmer I试验(SIaT)等检查,并按不同治疗方法分成3组,A组使用0.02%氟米龙滴眼液滴眼24眼; B组使用茶树精油(TTO)湿巾敷眼26眼; C组用0.02%氟米龙滴眼液滴眼联合TTO湿巾敷眼26眼,随访4wk。

结果：118眼中76眼(64.4%)睫毛蠕形螨镜检为阳性。睫毛蠕形螨阳性的三组患者治疗后的主观症状评分均较治疗前有改善(P<0.05)。治疗后A组蠕形螨数量较治疗前无显著差异(P=0.11); B、C组较治疗前明显减少(均P<0.01)。三组患者BUT治疗前后比较,A组BUT无显著差异(P=0.22); B、C组BUT明显延长(均P<0.05)。治疗后C组的BUT较A、B组明显延长(均P<0.05)。三组患者治疗前后的FL评分均较治疗前明显改善(P<0.05)。

结论：老年MGD患者睫毛蠕形螨感染率较高,睑板腺热疏通后TTO湿巾联合0.02%氟米龙滴眼液能有效驱螨、缓解MGD患者局部症状。     

Fructooligosaccharide enhanced absorption and anti-dyslipidemia capacity of tea flavonoids in high sucrose-fed mice

The ingestion of tea flavonoids (TF) and fructooligosaccharide (FOS) contributes to anti-hyperlipidaemia. In the current study, TF or FOS or TF together with FOS were orally administrated to mice fed a high sucrose (HS) diet. UPLC-MS analyses showed that FOS significantly increased the concentrations of urine catechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate and gallocatechin gallate. The mice fed with HS for continuous 8?weeks exhibited severe dyslipidemia and abnormal liver fat accumulation. However, oral administration of FOS or TF or in combination significantly decreased the effects of HS on the serum total cholesterol, total triglycerides, low-density lipoprotein and high-density lipoprotein. Co-treatment of FOS and TF more effectively regulated lipid metabolism by inhibiting lipogenesis. Intake of TF together with FOS reduced the level of dyslipidemia marker (elaidic acid) by increasing anti-oxidative activity than treatments of FOS or TP alone in HS-fed mice. Histological observations of liver confirmed these health benefits.     

Polyphenol Mechanisms against Gastric Cancer and Their Interactions with Gut Microbiota: A Review

The lack of new drugs and resistance to existing drugs are serious problems in gastric cancer(GC) treatment. The research found polyphenols possess anti-Helicobacter pylori(Hp) and antitumor activities and may be used in the research and development of drugs for cancer prevention and treatment. However, polyphenols are affected by their chemical structures and physical properties, which leads to relatively low bioavailability and bioactivity in vivo. The intestinal flora can improve the absorption, utilization, and biological activity of polyphenols, whereas polyphenol compounds can increase the richness of the intestinal flora, reduce the activity of carcinogenic bacteria, stabilize the proportion of core flora, and maintain homeostasis of the intestinal microenvironment. Our review summarizes the gastrointestinal flora-mediated mechanisms of polyphenol against GC.     

Mycotoxins in Tea ((Camellia sinensis (L.) Kuntze)): Contamination and Dietary Exposure Profiling in the Chinese Population

Tea is popular worldwide with multiple health benefits. It may be contaminated by the accidental introduction of toxigenic fungi during production and storage. The present study focuses on potential mycotoxin contamination in tea and the probable dietary exposure assessments associated with consumption. The contamination levels for 16 mycotoxins in 352 Chinese tea samples were determined by ultra-performance liquid chromatography–tandem mass spectrometry. Average concentrations of almost all mycotoxins in tea samples were below the established regulations, except for ochratoxin A in the dark tea samples. A risk assessment was performed for the worst-case scenarios by point evaluation and Monte Carlo assessment model using the obtained mycotoxin levels and the available green, oolong, black, and dark tea consumption data from cities in China. Additionally, we discuss dietary risk through tea consumption as beverages and dietary supplements. In conclusion, there is no dietary risk of exposure to mycotoxins through tea consumption in the Chinese population.