variations of main quality components of tea genetic resources [camellia sinensis (l.) o. kuntze] preserved in the china national germplasm tea repository.the variations of the main quality components of tea, tea polyphenols, catechins, amino acids, caffeine, and water extract of 596 accessions chinese tea genetic resources, preserved in the china national germplasm tea repository (cngtr), were analyzed. tea polyphenols content on a dry weight basis varied from 13.6 to 47.8%, averaging 28.4%. the tea polyphenols content increases gradually from northern and eastern provinces to southern provinces, the highest is in yunnan tea resources. the conten ...200515898357
[genetic diversity of camellia sinensis germplasm in guangdong province based on morphological parameters and srap markers].by the methods of phenotypic identification and srap makers amplification, the genetic diversity of twenty-five local tea cultivars in guangdong province and five contrastive cultivars from other regions was assessed and classified, and the phenotypic traits of the cultivars were clustered by pearson correlation and farthest neighbor methods. the coefficient of variation of the phenotypic traits was averagely 32.15%. fine-hair had the highest coefficient of variation (42.41%), while the growth p ...200919899450
exposure and risk assessment for aluminium and heavy metals in puerh the consumption of puerh tea is booming because of its multiple health-promoting effects, the possible health risks resulting from long-term exposure to metals contained in this tea need to be evaluated. to assess the human risk associated with drinking puerh tea, concentrations of aluminium, lead, cadmium, mercury, zinc, copper and arsenic were determined in samples of puerh tea, tea leaves from the plants, and planted soil collected from the yunnan province, china. site-specific exposure pa ...201020413147
heterozygosities and genetic relationship of tea cultivars revealed by simple sequence repeat markers and implications for breeding and genetic mapping programs.genetic maps are essential tools for quantitative trait locus analysis and marker-assisted selection breeding. in order to select parents that are highly heterozygous for genetic mapping, the heterozygosity (hs) of 24 tea cultivars (camellia sinensis) was analyzed with 72 simple sequence repeat markers. in total, 359 alleles were obtained with an average of 4.99 per marker. the hs varied greatly from 37.5 to 71.0% with an average of 51.3%. on average, tea cultivars from fujian province showed a ...201525867299
cellular antioxidant, methylglyoxal trapping, and anti-inflammatory activities of cocoa tea (camellia ptilophylla chang).cocoa tea (camellia ptilophylla chang) is a naturally low caffeine-containing but gallocatechin gallate (gcg)-rich tea cultivar, though its biological activities have not been extensively explored. herein, we evaluated the in vitro cellular antioxidant, methylglyoxal trapping, and anti-inflammatory activities of water extract of green tea from cocoa tea (cwe) and yunnan daye tea (camellia sinensis) (ywe), and their predominant bioactive components gcg and epigallocatechin gallate (egcg) for comp ...201728725904
novel acetylcholinesterase inhibitors from zijuan tea and biosynthetic pathway of caffeoylated catechin in tea plant.zijuan tea is a special cultivar of yunnan broad-leaf tea (camellia sinensis var. assamica) with purple buds, leaves, and stems. phytochemical study on this tea led to the discovery of three hydroxycinnamoylated catechins (hccs) (1-3), seven other catechins (4-10), three proanthocyanidins (11-13), five flavones and flavone glycosides (14-18), two alkaloids (19, 20), one steroid (21), and one phenylpropanoid glycoside (22). the isolation and structural elucidation of the caffeoylated catechin (1) ...201728763966
interactions among chemical components of cocoa tea (camellia ptilophylla chang), a naturally low caffeine-containing tea the 1980s, a novel tea species, cocoa tea (camellia ptilophylla chang), was discovered in southern china with surprisingly low caffeine content (0.2% by dry weight). although its health promoting characteristics have been known for a while, a very limited amount of scientific research has been focused on cocoa tea. herein, a systematic study on cocoa tea and its chemical components, interactions and bioactivities was performed. yd tea (yunnan daye tea, camellia sinensis), a tea species with a ...201424699984
metabolite profiling of camellia sinensis by automated sequential, multidimensional gas chromatography/mass spectrometry reveals strong monsoon effects on tea constituents.seasonal variation in tea (camellia sinensis (l.) kuntze; theaceae) chemistry was investigated using automated sequential, multidimensional gas chromatography/mass spectrometry (gc-gc/ms). metabolite libraries were produced for teas harvested from the bulang mountains in yunnan, china before and after the onset of the east asian monsoon. a total of 201 spring and 196 monsoon metabolites were identified, with 169 common and 59 seasonally unique compounds. an additional 163 metabolites were detect ...201425454147
carboxymethyl- and carboxyl-catechins from ripe pu-er tea.ripe pu-er tea, a special microbial postfermented tea originated from yunnan province, china, since ancient times, is made from green pu-er tea prepared from the leaves of camellia sinensis var. assamica (theaceae). chemical investigation on thearubigin (n-buoh-soluble) fraction of the commercial ripe pu-er tea, led to the identification of four new flavan-3-ol derivatives, 8-carboxymethyl-(+)-catechin (1), 8-carboxymethyl-(+)-catechin methyl ester (2), 6-carboxymethyl-(+)-catechin (3), and 6-ca ...201425455197
simultaneous determination of free amino acids in pu-erh tea and their changes during fermentation.pu-erh ripened tea is produced through a unique microbial fermentation process from the sun-dried leaves of large-leaf tea species (camellia sinensis (linn.) var. assamica (masters) kitamura) in yunnan province of china. in this study, the changes of amino acid profiles during fermentation of pu-erh tea were investigated, based on the improved hplc-uv method with pitc pre-column derivatization for the simultaneous determination of twenty free amino acids. results showed that aspartic acid, gluta ...201626471603
bacterial and fungal communities in pu'er tea samples of different ages.pu'er is a major kind of postfermented tea and is made with a "large leaf" variety of camellia sinensis (c. sinensis assamica), whose distribution is limited to the mountains of southern yunnan, china. the quality of pu'er tea is believed to increase with storage (aging, maturing) because of postfermentation by microbes. the effect of storage period (from < 1 to 192 mo) on the bacteria and fungi in pu'er tea was investigated by a culture-dependent and a pcr-dgge method. the individual numbers of ...201323957415
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