Fermentation is one of the key steps to produce high-quality black tea, during which the chemical compositions change dramatically. However, the dynamic changes of this sophisticated process are far from clear, and are often characterized through identifying a few compounds. A nontargeted metabolomics approach using Agilent ultrahigh performance liquid chromatography coupled with quadrupole tim...

Kombucha tea (KT) is sugared black tea fermented with a symbiotic culture of acetic acid bacteria and yeasts, which is said to be tea fungus. KT is claimed to have various beneficial effects on human health, but there is very little scientific evidence available in the literature. In the present study, KT along with black tea (BT) and black tea manufactured with tea fungus enzymes (enzyme-proce...

The inhibition of elements of the plasminogen activator system [urokinase (uPA), tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1)] plays an important role in human diseases. PAI-1 is overexpressed in obesity and diabetes, and the inhibition of this protein has been postulated to alleviate the symptoms of both disorders. We found that two theaflavins (TFs) from bl...

conclusions herbal tea of fenugreek seed in comparison to the control group improves the signs of breast milk sufficiency. results before the intervention there was no significant difference between weight, height, head circumference, the number of wet diapers and frequency of defecation between the two groups (p > 0.05), yet the number of breast feeding times of the control group was more than...

The aim of this work was to validate the method of determination of polycyclic aromatic hydrocarbons (PAHs), i.e., benzo(a)pyrene and sum of benzo(a)pyrene, benz(a)anthracene, benzo(b)fluoranthene and chrysene in different types of tea, as well as to assess the transfer of these contaminants from tea to tea infusion. The research materials were popular types of black, green, red and white tea. ...

The objectives of this study were to determine the major components in tea leaves and tea extracts and to study the relationship between chemical content and antimutagenic activity of various tea extracts. The amount of catechins in various tea extracts was in the order: green tea (26.7%) > oolong tea (23.2%) > pouchong tea (15.8%) > black tea (4.3%). The amounts of caffeine and phenolic compou...

Tea extracts are used in many over-the-counter preparations claiming to promote weight loss. The rationale for this usage includes reports that green tea extract increases thermogenesis, and extracts of green and black tea and mulberry leaf inhibit the digestion/absorption of carbohydrate and fat. The investigators in this study tested the potential of increasing doses of a mixture of three ext...

Fenpyroximate is an effective acaricide on several food crops. In the present study, dissipation of residue of this acaricide in black tea, tea infusion and spent tea was studied. Analysis was carried out using high performance liquid chromatography with diode array detection. The rate of dissipation was found to vary with the nature of the substrate. In tea leaves the half-life of fenpyroximat...

Puerh tea is a unique Chinese fermented tea. Unlike other teas it is stored for a long period of time. Aspergillus niger is claimed to be the dominant microorganism in the Puerh tea manufacturing process and also to be common on tea in general. A. niger sensu stricto is known to produce the mycotoxins ochratoxin A, fumonisins B(2) and B(4). With this in mind, we performed a preliminary study to...

BACKGROUND Circulating neopterin and the ratio of kynurenine to tryptophan (KYN/TRP) concentrations are biomarkers of immune activation that have been linked to cardiovascular and total mortality. Several in vitro studies indicated that tea flavonoids and other antioxidants can modulate tryptophan breakdown rates and neopterin production in immune cells. We aimed to assess the effects of regula...