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PubMedDate not supplied

The distribution of minerals and flavonoids in the tea plant (Camellia sinensis).

Camellia sinensis is a plant growing in India, Sri Lanka, Java, Japan and its properties were known 4000 years ago. Since then, traditional Chinese medicine has recommended this plant for headaches, body aches and pains, digestion, depression, detoxification, as an energiser and, in general, to prolong life. Tea contains volatile oils, vitamins, minerals, purines, polyphenols, particularly carechins. We have analysed ten commercial teas from various countries to determine their mineral composition and we have analysed a green tea, an Oolong tea and a White tea to determine their polyphenols and flavonoids content. Our study shows that the variation of mineral composition, polyphenols and flavonoids are linked to different origins of the plant. For the determination of phenols compounds and flavonoids we used an HPLC apparatus and for mineral analysis an atomic absorption apparatus.

Anticholesteremic Agents↗
PubMed1995

Detection of genetic diversity in tea (Camellia sinensis) using RAPD markers.

Camellia sinensis is a beverage tree crop native to Southeast Asia and introductions have been made into several nonindigenous countries. No systematic assessment of genetic variability in tea has been done anywhere. In this study, random amplified polymorphic DNA (RAPD) analysis was used to estimate genetic diversity and taxonomic relationships in 38 clones belonging to the three tea varieties, assamica, sinensis, and assamica ssp. lasiocalyx. Extensive genetic variability was detected between species, which was partitioned into between and within population components. Seventy percent of the variation was detected within populations. Analyses based on band sharing separated the three populations in a manner consistent with both the present taxonomy of tea and with the known pedigrees of some clones. RAPD analysis also discriminated all of the 38 commercial clones, even those which cannot be distinguished on the basis of morphological and phenotypic traits.

Base Sequence↗
PubMed2005

Water deficit induced oxidative damage in tea (Camellia sinensis) plants.

When the tea (Camellia sinensis) leaf water potential was -1.1 MPa (Moderate water deficit), there was 58% inhibition of photosynthesis accompanied by increased zeaxanthin, malondialdehyde, oxidized proteins and superoxide dismutase activity. When the leaf water potential was -2MPa (severe water deficit), there was nearly complete inhibition of photosynthesis apart from a decrease in chlorophylls, beta-carotene, neoxanthin and lutein. Water deficit at this level caused further conversion of violaxanthin to zeaxanthin, suggesting damage to the photosynthetic apparatus. There were consistent decreases in antioxidants and pyridine nucleotides, and accumulation of catalytic Fe, malondialdehyde and oxidized proteins. It is inferred that, in tea plants, the increase in catalytic Fe and the decrease in antioxidant protection may be involved in the oxidative damage caused by severe water deficit, but not necessarily in the incipient stress induced by moderate water deficit.

Antioxidants↗
PubMed2007

Effect of nitrogen form and root-zone pH on growth and nitrogen uptake of tea (Camellia sinensis) plants.

BACKGROUND AND AIMS: Tea (Camellia sinensis) is considered to be acid tolerant and prefers ammonium nutrition, but the interaction between root zone acidity and N form is not properly understood. The present study was performed to characterize their interaction with respect to growth and mineral nutrition. METHODS: Tea plants were hydroponically cultured with NH4+, NO3- and NH(4+) + NO3-, at pH 4.0, 5.0 and 6.0, which were maintained by pH stat systems. KEY RESULTS: Plants supplied with NO3- showed yellowish leaves resembling nitrogen deficiency and grew much slower than those receiving NH4+ or NH(4+) + NO3- irrespective of root-zone pH. Absorption of NH4+ was 2- to 3.4-fold faster than NO3- when supplied separately, and 6- to 16-fold faster when supplied simultaneously. Nitrate-grown plants had significantly reduced glutamine synthetase activity, and lower concentrations of total N, free amino acids and glucose in the roots, but higher concentrations of cations and carboxylates (mainly oxalate) than those grown with NH4+ or NH(4+) + NO3-. Biomass production was largest at pH 5.0 regardless of N form, and was drastically reduced by a combination of high root-zone pH and NO3-. Low root-zone pH reduced root growth only in NO(3-)-fed plants. Absorption of N followed a similar pattern as root-zone pH changed, showing highest uptake rates at pH 5.0. The concentrations of total N, free amino acids, sugars and the activity of GS were generally not influenced by pH, whereas the concentrations of cations and carboxylates were generally increased with increasing root-zone pH. CONCLUSIONS: Tea plants are well-adapted to NH(4+)-rich environments by exhibiting a high capacity for NH4+ assimilation in their roots, reflected in strongly increased key enzyme activities and improved carbohydrate status. The poor plant growth with NO3- was largely associated with inefficient absorption of this N source. Decreased growth caused by inappropriate external pH corresponded well with the declining absorption of nitrogen.

Amino Acids↗
PubMed2005

[RAPD analysis on genetic diversity of the preconcentrated core germplasms of Camellia Sinensis in China].

The study was to evaluate the genetic diversity of 69 tea cultivars of the preconcentrated core germplasms of Camellia Sinensis in China by the random amplified polymorphic DNA (RAPD). Among 50 arbitrary primers, 32 primers could generate enough amplified bands for all the strains in this study. Among a total of 348 bands observed, 328 (94.3%)bands were polymorphic in the 69 cultivars tested except additional 20 cultivars. Genetic distances between the cultivars varied from 0.223 to 0.723. The study indicated that the pre-concentrated core germplasms of Camellia Sinensis in China could well represent the whole collection in respect of genetic structure and genetic diversity and genetic distance. At the same time, it was the best option to establish core collection of Camellia Sinensis in China by combining morphological markers with DNA molecular markers.

Base Sequence↗
PubMed2002

Development of CAPS markers based on three key genes of the phenylpropanoid pathway in tea, Camellia sinensis (L.) O. Kuntze, and differentiation between assamica and sinensis varieties.

The genetic diversity of tea, Camellia sinensis (L.) O. Kuntze, including the two main cultivated sinensis and assamica varieties, was investigated based on PCR-RFLP analysis of PAL, CHS2 and DFR, three key genes involved in catechin and tannin synthesis and directly responsible for tea taste and quality. Polymorphisms were of two types: amplicon length polymorphism (ALP) due to the presence of indels in two introns of PAL and DFR, and point mutations detected after restriction of amplified fragments with appropriate enzymes. A progeny test showed that all markers segregated in a Mendelian fashion and that polymorphisms were exclusively co-dominant. CHS2, which belongs to a multi-gene family, allowed for greater variation than the single-copy PAL gene. Based on Nei's gene diversity index, var. sinensis was revealed to be more variable than var. assamica, and that a higher proportion of overall diversity resided within varieties as compared to between varieties. Even though no specific DNA profile was found for either tea varieties following any single PCR-RFLP analysis, a factorial correspondence analysis carried out on all genotypes and markers separated the tea samples into two distinct groups according to their varietal status. This reflects the large difference between var. sinensis and var. assamica in their polyphenolic profiles. The STS-based markers developed in this study will be very useful in future mapping, population genetics and fingerprinting studies of this important crop species and other Camellia species, as the primers have also proven successful in the three other subgenera of this genus.

Acyltransferases↗
PubMed2003

The impact of pH and calcium on the uptake of fluoride by tea plants (Camellia sinensis L.).

BACKGROUND AND AIMS: Tea plants (Camellia sinensis L.) accumulate large amounts of fluoride (F) from soils containing normal F concentrations. The present experiments examined the effects of pH and Ca on F uptake by this accumulating plant species. METHODS: The effect of pH was assessed in two experiments, one using uptake solutions with different pHs, and the other using lime, as CaO, applied to the soil. The effect of Ca was examined by analysing F concentrations in plants supplied with varying amounts of Ca, as Ca(NO3)2, either in uptake solutions or through the soil. KEY RESULTS: F uptake was highest at solution pH 5.5, and significantly lower at pH 4.0. In the soil experiment, leaf F decreased linearly with the amounts of lime, which raised the soil pH progressively from 4.32 to 4.91, 5.43, 5.89 and, finally, 6.55. Liming increased the water-soluble F content of the soil. Including Ca in the uptake solution or adding Ca to soil significantly decreased leaf F concentrations. The distribution pattern of F in tea plants was not altered by Ca treatment, with most F being allocated to leaves. The activity of F- in the uptake solution was unaffected and water-soluble F in the soil was sometimes increased by added Ca. CONCLUSIONS: F uptake by tea plants, which are inherently able to accumulate large quantities of F, was affected both by pH and by Ca levels in the medium. The reduced F uptake following Ca application appeared not to be due simply to the precipitation of CaF2 in solution and soil or to the complexing of Ca and F in roots, although these factors cannot be dismissed. It was more likely due to the effect of Ca on the properties of cell wall or membrane permeability in the solution experiments, and to alteration of F speciations and their quantities in soil solutions following Ca application.

Calcium↗
PubMed2006

Inhibition of pathogenic bacterial adhesion by acidic polysaccharide from green tea (Camellia sinensis).

An acidic polysaccharide CS-F2 from Camellia sinensis was examined to characterize its anti-adhesive effects against pathogenic bacteria, most notably Helicobacter pylori, Propionibacterium acnes, and Staphylococcus aureus. CS-F2 showed marked inhibitory activity against the pathogen-mediated hemagglutination with a minimum inhibitory concentration (MIC) between 0.01 and 0.1 mg/mL, which is lower than the previously reported MIC values for Panax ginseng and Artemisia capillaris. The inhibitory effects of CS-F2 on the adhesion of H. pylori to AGS adenocarcinoma gastric epithelial cells, or P. acnes and S. aureus to NIH 3T3 fibroblast cells, were further assessed resulting in MIC values between 0.063 and 0.13 mg/mL. Importantly, CS-F2 showed no inhibitory effects against Lactobacillus acidophilus, Escherichia coli, or Staphylococcus epidermidis. Our results suggest that CS-F2, which is a pectin-type polysaccharide with a molecular weight of approximately 8.0 x 10(4) Da, may exert a selective anti-adhesive effect against certain pathogenic bacteria, while exerting no effects against beneficial and commensal bacteria.

Animals↗
PubMed2006

A comparative study on the antimutagenic properties of aqueous extracts of Aspalathus linearis (rooibos), different Cyclopia spp. (honeybush) and Camellia sinensis teas.

Antimutagenic activity of aqueous extracts of the South African herbal teas, Aspalathus linearis (rooibos) and Cyclopia spp. (honeybush) was compared with that of Camellia sinensis (black, oolong and green) teas in the Salmonella mutagenicity assay using aflatoxin B(1) (AFB(1)) and 2-acetylaminofluorene (2-AAF) as mutagens. The present study presents the first investigation on antimutagenic properties of C. subternata, C. genistoides and C. sessiliflora. The herbal teas demonstrated protection against both mutagens in the presence of metabolic activation, with the exception of "unfermented" (green/unoxidised) C. genistoides against 2-AAF, which either protected or enhanced mutagenesis depending on the concentration. Antimutagenic activity of "fermented" (oxidised) rooibos was significantly (P<0.05) less than that of Camellia sinensis teas against AFB(1), while for 2-AAF it was less (P<0.05) than that of black tea and similar (P>0.05) to that of oolong and green teas. Antimutagenic activity of unfermented C. intermedia and C. subternata exhibited a similar protection as fermented rooibos against AFB(1). Against 2-AAF, fermented rooibos exhibited similar protective properties than unfermented C. intermedia and C. sessiliflora. Unfermented rooibos was less effective than the C. sinensis teas and fermented rooibos, but had similar (P>0.05) antimutagenicity to that of fermented C. sessiliflora against AFB(1) and fermented C. subternata against 2-AAF. Fermented C. intermedia and C. genistoides exhibited the lowest protective effect against 2-AAF, while fermented C. intermedia exhibited the lowest protection when utilising AFB(1) as mutagen. Aspalathin and mangiferin, major polyphenols in rooibos and Cyclopia spp., respectively, exhibited weak to moderate protective effects when compared to the major green tea catechin, (-)epigallocatechin gallate (EGCG). Antimutagenic activity of selected herbal tea phenolic compounds indicated that they contribute towards (i) observed antimutagenic activity of the aqueous extracts against both mutagens and (ii) enhancement of the mutagenicity of 2-AAF by unfermented C. genistoides. Antimutagenic activity of the South African herbal teas was mutagen-specific, affected by fermentation and plant material, presumably due to changes and variation in phenolic composition.

2-Acetylaminofluorene↗
PubMed2005

Flavanols in somatic cell division and male meiosis of tea (Camellia sinensis) anthers.

Young anthers excised from closed tea flower buds ( Camellia sinensis L.) were stained as fresh tissues with p-dimethylaminocinnamaldehyde reagent to localize flavanols associated with nuclei and chromosomes, apart from those flavanols stored in vacuoles. This staining reagent yields a blue colour for flavanols. In the nonsporogenic somatic cells of developing anthers, flavanols were found to be attached to chromosomes at all mitotic stages. Male meiosis started at a bud size of about 3.5 mm in diameter in pollen mother cells which displayed generally more or less pronounced blue nuclei and cytoplasm. The meiotic divisions from prophase I to telophase II were characterized by blue stained nuclei and chromosomes, but within the cytoplasm there was, if any, a random and very poor reaction for flavanols. Metaphase and telophase of meiotic divisions showed maximally condensed chromosomes staining dark blue. Early in telophase II, the cytoplasm was again stained blue; this faded at late tetrad stage. Flavanols of young mitotic and older non-mitotic anthers were determined using high pressure liquid chromatography--chemical reaction detection (HPLC-CRD). Catechin, epicatechin, B2, and epigallocatechin were minor compounds, whereas epicatechin gallate and epigallocatechin gallate were found in higher amounts. The major flavanol compound of the anthers, epicatechin gallate, exhibited a significant affinity to histone sulphate, as shown by UV-VIS spectroscopic titration.

Camellia sinensis↗
PubMed1990

[Anti-caries effects of polyphenol compound from Camellia sinensis].

Polyphenol compound (designated Sunphenon) from leaf of Camellia sinensis have been partially purified by extraction of the boiling water with ethyl acetate. The effect of Sunphenon on cariogenic Streptococcus mutans groups (serotype c and g) was studied in both in vitro and in vivo. The summary of results were described as follows; 1) Addition of Sunphenon to S. mutans JC-2 (c) caused a decrease in cell viability. The activity of Sunphenon showed that multiple application are required for killing and maximum effect was seen between 60 and 90 min treatment. However, treatment of S. mutans with Sunphenon did not induce complete cell death after 90 min incubation. 2) When S. mutans JC-2 (c) was pretreated with Sunphenon, the cellular attachment on saliva-treated hydroxyapatite surface was significantly reduced. 3) When saliva-treated hydroxyapatite surface was pretreated with Sunphenon, the cellular attachment of S. mutans JC-2 (c) was also markedly inhibited. 4) Sunphenon had no inhibitory effect on lactic acid production by S. mutans JC-2 (c). 5) Sunphenon showed a strong inhibitory effect against water-insoluble glucan synthesis by glucosyltransferase from S. mutans JC-2 (c) or S. sobrinus 6715 (g). 6) specific pathogen-free rats infected with S. mutans JC-2 (c) and fed a cariogenic diet containing 0.5%. Sunphenon developed significantly fewer carious lesions than controls infected with S. mutans and fed the same diet without Sunphenon. Furthermore, feeding of the drinking water containing 0.1% Sunphenon reduced caries incident in S. mutans in infected animals.

Animals↗
PubMed2004

Increased microbicidal activity of green tea (Camellia sinensis) in combination with butylated hydroxyanisole.

We have demonstrated that green tea (Camellia sinensis) shows increased antimicrobial activity against bacteria and fungi when used in combination with butylated hydroxyanisole (BHA). Glycolic extract taken from green tea showed only limited activity against Streptococcus mutans and no activity against Candida albicans and certain strains of Escherichia coli. BHA, at non inhibitory concentrations, increased the microbicidal activity of green tea against 10(10) S. mutans (p<0.01), non-susceptible E. coli (p<0.01) and C. albicans (p<0.01). Green tea in combination with BHA reduced the hydrophobicity of S. mutans (p<0.01) and greatly inhibited (p<0.001) the formation of hyphae in C. albicans. The increased antimicrobial activity of green tea is related to an impairment of the barrier function in microorganisms and a depletion of thiol groups. The increased activity of green tea as an oral antimicrobial product is discussed.

Anti-Bacterial Agents↗
PubMed2005

Camellia sinensis: historical perspectives and future prospects.

As the source of brewed tea preparations, Camellia sinensis has operated for centuries at the interface of agriculture, politics, and biology. The purpose of this review is to present an inter-disciplinary survey of issues surrounding cultivation, processing, and consumption of the tea plant. Particular attention is given to the biologic effects of tea: first, assessing at the level of human physiology its value as a chemopreventive and chemotherapeutic agent; second, examining effects of production upon local ecosystems, due to resource demands and industrial farming practices. In sum, C. sinensis emerges as a potentially powerful contributor to both public health and economic growth if its role is managed from a prospective, sustainable, and evidence-based vantage.

Agriculture↗
PubMed2003

Regulation of hazardous exposure by protective exposure: modulation of phase II detoxification and lipid peroxidation by Camellia sinensis and Swertia chirata.

Many natural compounds are now known to have a modulatory role on physiological functions and biotransformation reactions involved in the detoxification process, thereby affording protection from cytotoxic, genotoxic, and metabolic actions of environmental toxicants. As part of a programme on evaluation of food, beverage, and traditional medicinal plants for their anticarcinogenic activity, their effects on detoxification enzymes were also studied. The present report deals with Camellia sinensis and Swertia chirata. The effect of water infusions as well as crude and purified components of these plants on glutathione-S-transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) was analyzed in mice that were exposed to the chemical carcinogen DMBA. All the four enzymes were found to be activated in different degrees following treatment. The effect of Theaflavin, a component of black tea, was highly significant. The activation of the enzymes was accompanied by significant reduction in lipid peroxidation. The observation suggest the chemopreventive potential of both Camellia sinensis and Swertia chirata.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1997

Microbiological activity of whole and fractionated crude extracts of tea (Camellia sinensis), and of tea components.

Aqueous extracts of teas (Camellia sinensis) of different types and from various sources inhibited a wide range of pathogenic bacteria, including methicillin-resistant Staphylococcus aureus. Tea extracts were bactericidal to staphylococci and Yersinia enterocolitica at well below 'cup of tea' concentrations. Activity was confined to one of four fractions obtained from a green tea extract by partition chromatography. Testing of pure tea compounds and closely related chemicals suggested that the antibacterial activity of extracts of green tea can be explained by its content of epigallocatechin, epigallocatechin gallate and epicatechin gallate. In black tea extracts, theaflavin and its gallates are additional antibacterially active components.

Anti-Bacterial Agents↗
PubMed2001

Anticariogenic effects of black tea (Camellia sinensis) in caries prone-rats.

OBJECTIVE: Black tea (Camellia sinensis) may have anticariogenic properties. The present study was designed to determine whether consumption of black tea influences cariogenesis in young, caries-prone rats. METHOD AND MATERIALS: Eighteen-day-old Sprague-Dawley rats (n = 24; eight per group) fed a cariogenic diet (MIT 200) were randomly assigned to three groups to receive deionized, distilled fluoride-free water, tea, or fluoridated water (25 ppm), ad libitum, for 14 days. In addition, an initial control group of rats was studied at 20 days of age. Teeth were stained with silver nitrate to detect caries and cut mesiodistally. First and second molars were assessed for caries. RESULTS: The initial control group had negligible caries. Caries-prone rats consuming fluoride-free water had significantly more caries lesions (6.75) than did the tea (3.12) and the fluoridated water (0.85) groups. CONCLUSION: Consumption of black tea for 2 weeks attenuated development and progression of caries in caries-prone young rats.

Analysis of Variance↗
PubMed2004

Caffeine in tea plants [Camellia sinensis (L) O. Kuntze]: in situ lowering by Bacillus licheniformis (Weigmann) Chester.

Tea plants (Camellia sinensis) contain 5-6% caffeine that is responsible for the stimulating effect of the beverage. As the tolerance to caffeine varies among individuals, low caffeine tea would be an ideal alternative. While assessing the potential of a few selected bacteria-Bacillus licheniformis, B. subtilis and B. firmus, to multiply on nutrient medium supplemented with glucose (5%) and tea leaf extract (2%), it was observed that only B. licheniformis could proliferate on this medium. Hence, B. licheniformis was used for further studies. Tea plants were sprayed with a suspension of B. licheniformis at a dilution of 5 x 10(8) CFU/ml containing 0.1% Tween 80 as surfactant. In situ lowering of caffeine from tea leaves was evident without affecting the quality of the other tea components. Further, there was no change in the morphological and physiological characteristics as well. It is suggested that spraying of B. licheniformis may be useful in yielding decaffeinated tea with good flavour and aroma.

Bacillus↗