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[en] Tea is one of the important liquids that people drink.In Iraq, tea is the main beverage after water.The tea plant is known scientifically as Camellia sinensis, when planting and during growth needs to fertilizers, which contents remarkable amounts of Uranium.So it became important to study the concentrations of uranium found in tea.Eight samples of tea had been taking, which represent the most important species used in the Iraqi kitchen, and the Uranium concentrations were measured.The results showed that the average concentration of uranium for all samples were 1.005 mg/L, while the average of the annual effective dose was 0.221 mSν/y.The results also indicated that green tea possesses small concentration of Uranium compared with other species
[en] Over 10 centuries, ancient cultivated tea populations (Camellia sinensis var. assamica) are still planted merely in Yunnan province of China. Genetic diversity and differentiation were examined in 10 ancient tea plantations by using ISSR markers. The average genetic diversity within populations, estimated with Nei's genetic diversity (HE), was approximately 0.2809, while Shannon indices (HO) was 0.4179. The percentage of polymorphic loci (P) of the 10 populations ranged from 56.5% to 90.91%. We found a moderate level of genetic differentiation among population as evidenced by the coefficients of gene differentiation (Gst) of 0.3911 and the analysis of molecular variance (AMOVA) of 39.70%. The result could be explained by the nature of highly out crossing in the tea species as well as serious habitat fragmentation. Finally, conservation strategies were discussed to protect these ancient tea populations, including in situ reserve settings and ex situ germplasm sampling. (author)
[en] Tea (Camellia sinensis (L.) O. Kuntze is the most consumed beverage in the world. Six genotypic cultivars of tea, namely Indonesian, Sri Lankan, Ruopi, Qi men, Chuye and Japanese were taxonomically characterized by using morphogenetic approach. Randomized Completely Block Design (RCBD) technique was applied in the analysis and results were presented in form of phenogram. Taxonomically genotypes were divided into two clusters with genetic distance (GD) 4.5. The cluster-I contained four cultivars bifurcating into two sub-linages with difference of GD 3. Intra-cluster GD of between genotypes Japanese and Sir Lankan was 2.0 GD and Chuye and Ruopi genotypes were closely associated with 1.8 GD. The cluster-II indicated the trait homology between Indonesian and Qi Men populations was 1.4 GD. This demonstrates that Qi men and Indonesian genotype are genetically more closely related than other genotypes, may be originated from one ancestor. The qualitative character evaluation was conducted to explore adaptability of these genotypes to the environment. The vein pairs per leaf was highest in Indonesian (13.60), followed by Qi men (12.08). The internode distance was highest in Qi men (3.7 cm) succeeded by Ruopi (3.6 cm). The branch angle to stem value was 35 Degree in Qimen followed by Japanese with 38 Degree. This morphogenetic analysis shows that Qimen and Sri Lankan genotypes are congruently adapted to the environment which depicts that area is appropriate for the tea plant growth and cultivation. This analysis also reflects that although these tea cultivars are phenetically similar to each other but can be differentiated by use of numerical analysis. (author)
[en] The effect of air pollution is felt world wide. Acid rain brings havoc to all forms of life on this planet. One of the many consequences of acid rain is the release of luminum (III) from the soil. Tea is the plant which selectively accumulates soluble aluminium from the soil. The short article is to alert heavy tea drinkers as aluminium is a neuro-toxic metal. (author)
[en] The sensitivity to UV-B (290–320 nm) radiation of common phylloplane yeasts from two contrasting UV-B environments was compared in the laboratory using mixtures of white light (PAR: 400–700 nm) and UV-B radiation from artificial lamp sources. Sporidiobolus salmonicolor, Rhodotorula mucilaginosa and Cryptococcus sp., the dominant yeasts on leaves of tea (Camellia sinensis), were isolated in Sri Lanka (SL), while Sporidiobolus sp. and Bullera alba, dominant on faba bean (Vicia faba), were isolated in the U.K. Dose responses were determined separately for each yeast. UV-B reduced colony forming units (due to cell mortality or inactivation) and colony size (due to reduced multiplication) of all yeasts. The LD50 values and doses causing 50% reduction of cells per colony were higher for SL isolates than U.K. isolates. Results indicated that each yeast is somewhat vulnerable to UV-B doses representative of its natural habitat. The relative insensitivity of SL isolates was shown when SL and U.K. isolates were irradiated simultaneously with the same dose of UV-B. Of the two U.K. yeasts, B. alba was significantly more sensitive than Sporidiobolus sp. to UV-B. Except for R. mucilaginosa from SL, all yeasts demonstrated some photorepair in the presence of white light. White light provided relatively little protection for the U.K. isolate of Sporidiobolus sp. although it allowed increased colony size. The spectral responses of Sporidiobolus sp. (U.K.) and of B. alba (U.K.) were broadly similar. Wavelengths longer than 320 nm had no measurable effect on colony forming units. However, colony survival was significantly reduced at 310 nm and all shorter wavebands. No colonies were counted at 290 nm or below. (author)
[en] Tea and herbal infusions have been studied for their polyphenolic content, antioxidant activity and phenolic profile. The total phenolics recovered by ethyl acetate from the water extract, were determined by the Folin-Ciocalteu procedure and ranged from 88.1 ± 0.42 (Greek mountain tea) to 1216 ± 32.0 mg (Chinese green tea) GAE (Gallic acid equivalents)/cup. The antioxidant activity was evaluated by two methods, DPPH and chemiluminescence assays, using Trolox and quercetin as standards. The EC50 of herbal extracts ranged from 0.151 ± 0.002 mg extract/mg DPPH (0.38 quercetin equivalents and 0.57 Trolox equivalents), for Chinese green tea, to 0.77 ± 0.012 mg extract/mg DPPH (0.08 quercetin equivalents and 0.13 Trolox equivalents), for Greek mountain tea. Chemiluminescence assay results showed that the IC50 ranged from 0.17 ± 3.4 x 103 lg extract/ml of the final solution in the measuring cell (1.89 quercetin and 5.89 Trolox equivalents) for Chinese green tea, to 1.10 ± 1.86 x 102 g extract/ml of the final solution in the measuring cell (0.29 quercetin and 0.90 Trolox equivalents) for Greek mountain tea. The phenolic profile in the herbal infusions was investigated by LC-DAD-MS in the positive electrospray ionization (ESI) mode. About 60 different flavo- noids, phenolic acids and their derivatives have been identified. (author)
[en] Tea seed oil nano-particle emulsions were prepared. Non-ionic surfactants containing Tween 80 and Span 80 (1:1, w/w) were mixed with propanol (3-9:1, w/w) to give Smix, which was thereafter mixed with tea seed oil. The mixture was titrated with water at 150 rpm to give clear or bluish and bluish-white emulsions. Twelve nano-particle emulsions with 64.64 to 72.73% Smix, 16.66 to 27.27% oil and 9.09 to 16.67% water with particle sizes between 207.00 to 430.10 nm, PDI of 0 to 0.4, ζ-potential of -42.00 to -49.63 mV, pH of 7.04 to 7.32 and 151.33 to 241.93 cps, were stable following an accelerated stability test and long term storage at room temperature and 4 and 45 ºC for 90 days, although one system (16.66% oil and 66.67% Smix) was separated. This nano-particle emulsion formulation is concise and feasible for an industrial development of topical products containing tea seed oil.
[es]Se prepararon emulsiones de nanopartículas de aceite de semilla de té. Se mezclaron tensioactivos no iónicos que contenían Tween 80 y Span 80 (1:1, p/p) con propanol (3-9: 1, p/p) para dar Smix que después se mezcló con aceite de semilla de té. La mezcla se valoró con agua a 150 rpm para dar emulsiones claras o azuladas y blanco azulado. Doce emulsiones de nanopartículas con 64,64 a 72,73% de Smix, 16,66 a 27,27% de aceite y 9,09 a 16,67% de agua con tamaños de partícula entre 207,00 y 430,10 nm, PDI de 0 a 0,4, potencial ζ de -42,00 a -49,63 mV, PH de 7,04 a 7,32 y 151,33 a 241,93 cps, se mantuvieron estables tras el ensayo de estabilidad acelerada y almacenamiento a largo plazo a temperatura ambiente y 4 y 45 ºC durante 90 días, aunque uno de los sistemas (16,66% de aceite y 66,67% de Smix) se desvió. Esta formulación de emulsión de nanopartículas es concisa y factible para un desarrollo industrial de productos tópicos que contienen aceite de semilla de té.
[en] A study was conducted during 2007-08 and 2008-09 at National Tea Research Institute, Shinkiari, to evaluate the Impact of different doses of Urea Fertilizer on the yield of 20-year old tea-bushes. Basal doses of P and K were applied at the rate 45 and 30 kg acre/sup -1/, while N was applied in the form of Urea in two split doses, first in the month of March and second in the month of July, during both the years. The experiment was laid in Randomized Complete Block Design, with 05 treatments, replicated 04 times. The different levels of nitrogen in T1 to T5 were 175, 125, 75, 45 and 0 kg acre/sup -1/. It was observed that maximum plant-height and yield was obtained, during both the years, when maximum dose of N was applied in the form of Urea, with constant doses of P and K. (author)