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Needle Extract (needle + extract)

Distribution by Scientific Domains
Chemistry75%

Selected Abstracts

Effect of fungicides, endophytes and fungal filtrates on in vitro growth of Spanish isolates of Gremmeniella abietina

FOREST PATHOLOGY, Issue 4 2007
O. Santamarķa
Summary The effect of eight fungicides and 15 endophytes isolated from twigs of healthy Pinus halepensis trees on the growth rate of four Spanish isolates of the pathogen Gremmeniella abietina was evaluated in vitro. In the fungicide experiments, four doses of each fungicide tested were added to the growth medium. In the endophyte experiments, dual cultures endophyte-pathogen were paired in Petri dishes. Furthermore, growth of three G. abietina isolates was evaluated on malt agar with pine needle extract amended with filtrates from cultures of endophyte E14, which produced a brownish compound apparently inhibiting G. abietina growth. The results obtained suggested that chlorothalonil and daconil were the most suitable fungicides at low doses to reduce growth of G. abietina isolates from Spain. Four of the endophytes tested in vitro showed strong antagonistic activity against G. abietina and deserve further testing in vivo. The endophyte E14 produced in vitro a brownish compound which almost completely inhibited mycelial growth of G. abietina isolates from Spain. [source]

Evaluation of ELISA for imidacloprid detection in eastern hemlock (Tsuga canadensis) wood and needle tissues

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 2 2009
Brian M Eisenback
Abstract BACKGROUND: Imidacloprid is the primary insecticide used against the exotic invasive insect hemlock woolly adelgid, Adelges tsugae Annand, a pest of eastern hemlock [Tsuga canadensis (L.) Carričre] trees in the eastern United States. A competitive enzyme-linked immunosorbent assay (ELISA) was evaluated for quantification of imidacloprid in eastern hemlock wood and needle tissues. RESULTS: Matrix effects in the form of false positives and overestimated imidacloprid concentrations were observed in both wood and needle extracts. Tissues required a 100,1000-fold dilution with water in order to reduce matrix effects. Standard curves in 1% wood or needle extract were not significantly different from standard curves prepared in water. Matrix effects were more pronounced at concentrations in the lower working range of the kit, with recovery of 5 µg L,1 imidacloprid more accurate than recovery of 0.2 µg L,1. CONCLUSION: ELISA remains a valuable tool for semi-quantitative imidacloprid detection within the hemlock system because of its sensitivity, cost and ease of use. However, a 1000-fold dilution of hemlock tissue extract is recommended to ensure accurate imidacloprid determinations. Copyright © 2008 Society of Chemical Industry [source]

Simultaneous determination of main taxoids in Taxus needles extracts by solid-phase extraction-high-performance liquid chromatography with pentafluorophenyl column

BIOMEDICAL CHROMATOGRAPHY, Issue 1 2009
Yu-Jie Fu
Abstract A simple and accurate RP-HPLC method with pentafluorophenyl (PFP) column was developed for the simultaneous determination of six taxoids, i.e. paclitaxel, 10-deacetylbaccatin III (10-DAB III), 7-xylosyl-10-deacetyltaxol (7-xyl-10-DAT), 10-deacetyltaxol (10-DAT), cephalomannine and 7-epi-10-deacetyltaxol (7-epi-10-DAT), in the extracts from the needles of three Taxus species. The mobile phase consisted of acetonitrile (A) and water (B), and the extracts were separated using gradient elution program: 30% A at the first 7 min, and then ramped to 42% A at 8 min, held until 38 min. The developed method was validated with satisfactory precision (RSD < 2.61%), repeatability (RSD < 2.92%) and recovery (95.19,104.47%). The above taxoids in the extracts of Taxus cuspidata, T. chinensis and T. media were analyzed with the developed RP-HPLC method, and the results showed that the contents of different taxoids in three mentioned species were distinct. Maximal amounts of 10-DAB III, 7-xyl-10-DAT and 7-epi-10-DAT appeared in T. chinensis, while T. media possessed the highest content of 10-DAT, cephalomannine and paclitaxel. The developed method is accurate and efficient. It can be reliably used in the improved determination of taxoids for the quality control of Taxus species. Copyright © 2008 John Wiley & Sons, Ltd. [source]