Entity

Time filter

Source Type


Chen G.-H.,National Chung Hsing University | Yang C.-Y.,National Chung Hsing University | Lee S.-J.,National Chung Hsing University | Wu C.-C.,Tea Research and Extension Station | And 3 more authors.
Journal of Food and Drug Analysis | Year: 2014

The taste quality of oolong tea generated from leaves of Camellia sinensis L. cultivated in the same mountain area is positively correlated to the cultivation altitude, partly due to the inverse correlation with the astringency of the tea infusion. The astringency of oolong tea mostly results from the presence of polyphenolic compounds, mainly catechins and their derivatives. Four catechins, (-)-epicatechin (EC) and (-)-epigallocatechin (EGC) together with their gallate derivatives (with relatively high astringency), (-)-EC gallate (ECG) and (-)-EGC gallate (EGCG), were detected as major compounds in oolong tea. The degrees of catechin galloylation, designated as ECG/(EC + ECG) and EGCG/(EGC + EGCG), in both oolong tea infusions and their fresh tea leaves, were found to be inversely correlated to the cultivation altitude at 200 m, 800 m, and 1300 m. A similar inverse correlation was observed when seven more oolong tea infusions and seven more fresh leaves harvested at altitude ranging from 170 m to 1600 m were recruited for the analyses. Moreover, catechin contents in oolong tea infusions were also found to be inversely correlated to the cultivation altitude. It is proposed that catechin content and the degree of its galloylation account for, at least partly, the inverse correlation between the astringency of oolong tea and the cultivation altitude. © 2014, Food and Drug Administration, Taiwan.


Deng T.-C.,Agricultural Research Institute | Ning F.-Y.,Tea Research and Extension Station | Chen C.-T.,Agricultural Research Institute | Chou C.-M.,Agricultural Research Institute
Plant Protection Bulletin | Year: 2014

Most plants of Allium, except onion, are propagated with vegetative multiplication. Although blooming and seeding are common in Welsh onions, their economic cultivation mainly depend on tillers for division propagation. Therefore, the Welsh onion plants in the field are frequently infected by viruses and that causes the losses of quality and yield. The contagious viruses are readily transmitted from mother plants to the seedlings of next generation in which similar 'species degeneration' symptoms are appeared. Viruses infecting alliums, such as Garlic mite borne filamentous virus (GarMbFV), Garlic latent virus (GarLV), Shallot latent virus (SLV), Onion yellow dwarf virus (OYDV), Leek yellow stripe mosaic virus (LYSV), Shallot yellow stripe virus (SYSV) and Tobacco mosaic virus (TMV), in which SLV, LYSV, SYSV and OYDV have been documented to infect Welsh onions in Taiwan. Due to high probability of false-positive results from ELISA, three previously reported primers (Allex-CP (+)/Allex-NABP (-), OYDV. VKB 3F/OYDV. VKB 3R, and LYSV WA/LYSV WAR) and one newly designed primer pair (SLV-DF1/SLV-DR1) were adopted for reverse transcription polymerase chain reaction (RT-PCR) to detect the viruses. A survey for Welsh onions infected by viruses in Sansing Township, Yilan County indicated that SLV was the most prevalent while LYSV, SYSV and OYDV were occurred rarely. Accordingly, the specific pathogen-free (SPF) standard for SLV-free healthy seedlings of Welsh onion has been set. Three ways are commonly performed to raise healthy seedlings of Welsh onions: 1. screening of virus-free plants and from which to obtain tillers for division multiplication, 2. elimination of viruses by micro propagation to obtain healthy plantlets, and 3. selection of normal true seedlings from seed-sown materials. The yield trial showed that the growth potentials of healthy plants were significantly greater than SLV infected ones in height, weight, and stem diameter of plants. Through reproduction of three generations from virus-free tillers for division multiplication, plants of Welsh onion cv. Dawan yield more about 28% than that of non-screening seedlings. ©, 2014, Plant Protection Society of the Republic of China. All right reserved.


Hsu C.-P.,Yuanpei University | Shih Y.-T.,Yuanpei University | Lin B.-R.,National Taiwan University Hospital | Chiu C.-F.,Tea Research and Extension Station | Lin C.-C.,Yuanpei University
Journal of Agricultural and Food Chemistry | Year: 2012

One newly bred variety of tea cultivar, purple-shoot tea, was selected to evaluate its antiproliferative effects on colorectal carcinoma cells, as well as normal colon cells. The phytochemicals and identified catechins of purple-shoot tea extract (PTE) were significantly higher than that of ordinary tea, especially the anthocyanins (surpassed by 135-fold) and anthocyanidins (surpassed by 3.5-fold). PTE inhibited the proliferation of COLO 320DM (IC 50 = 64.9 μg/mL) and HT-29 (IC 50 = 55.2 μg/mL) by blocking cell cycle progression during the G 0/G 1 phase and inducing apoptotic death. Western blotting indicated that PTE induced cell cycle arrest by reducing the expression of cyclin E and cyclin D1 in COLO 320DM and the upregulation of p21 and p27 cyclin-dependent kinase inhibitors in HT-29. Two cells treated with PTE also indicated the cleavage of PARP, activation of caspase 3, and an increased Bax/Bcl-2 ratio. Our results showed that PTE is a potential novel dietary agent for colorectal cancer chemoprevention. © 2012 American Chemical Society.


Chuang Y.-H.,National Taiwan University | Chuang Y.-H.,Tea Research and Extension Station | Liu C.-H.,National Taiwan University | Tzou Y.-M.,National Chung Hsing University | And 3 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2010

Chemical surfactants or bio-surfactants intercalated into layered double hydroxides (LDHs) are considered as potential organic pollutant sorbents. This study evaluates the effects of (1) using either calcined or uncalcined LDH, and various solid/solution ratios, (2) the concentrations of the chemical surfactant sodium dodecyl sulfate (SDS) or the bio-surfactant rhamnolipid (RL), and (3) reaction temperatures and times on the synthesis of SDS-LDH and RL-LDH. Small angle X-ray diffraction (SAXRD) and X-ray diffraction (XRD) patterns reveal that using 1000mgL-1 RL intercalated 2:1 uncalcined LDH with 3 days reaction time, 0.5gL-1 solid/solution ratio, and temperature of 65°C to synthesize the RL-LDH, containing more organic carbon content, showing larger interlayer distance than SDS-LDH. RL-LDH shows subsequent higher efficiency of naphthalene sorption than SDS-LDH, depending on higher organic carbon contents and larger interlayer distance of RL-LDH. Since RL-LDH is environmentally friendly chemical, these results are of practical interesting in RL-LDH could be potentially employed as a sorbent for removal organic contaminants from aqueous solutions, and particularly in optimizing aquatic environment remediation technologies. © 2010 Elsevier B.V.


Hsieh S.-K.,National Chung Hsing University | Lo Y.-H.,National Chung Hsing University | Wu C.-C.,Tea Research and Extension Station | Chung T.-Y.,National Chung Hsing University | Tzen J.T.C.,National Chung Hsing University
Journal of Food and Drug Analysis | Year: 2015

Teaghrelins are unique acylated flavonoid tetraglycosides found in Chin-shin oolong tea, and have been demonstrated to be promising oral ghrelin analogues. The biosynthetic pathway of teaghrelins from quercetin-3-O-rutinoside (rutin) or kaempferol-3-O-rutinoside (nicotiflorin) was proposed to comprise three enzymatic steps according to the identification of putative intermediates in Chin-shin oolong tea. In addition to the two known teaghrelins in Chin-shin oolong tea, four teaghrelin-like compounds with different attachments of glycosides were identified in various oolong teas. Molecular modeling and docking were used to evaluate theoretically whether the putative biosynthetic intermediates of teaghrelins and the four teaghrelin-like compounds could be potential candidates of ghrelin analogues. The results showed that the attachment of a coumaroyl group was crucial for these tea compounds to bind to the ghrelin receptor. However, the additional attachment of a rhamnosyl glycoside to the flavonoid backbone of teaghrelin-like compounds at C-7 significantly reduced their binding affinity with the ghrelin receptor. © 2015.

Discover hidden collaborations