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Dereplication and chemotaxonomic studies of six marine algae of the Ochrophyta and one of the Rhodophyta phyla resulted in the detection of 22 separate compounds. All 16 secondary metabolites, including four new compounds (16–19), could be rapidly dereplicated using HPLC-NMR and HPLC-MS methodologies in conjunction with the MarinLit database. This study highlights the advantages of using NMR data (acquired via HPLC-NMR) for database searching and for the overall dereplication of natural products.  相似文献   
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Abstract

A feeding trial was performed to assess the potential beneficial effect of two levels of mannanoligosaccarides (MOS) on the growth performance, feed utilization, hematological parameters, and liver histopathology of gilthead seabream Sparus auratus (also known as gilthead bream). Mannanoligosaccarides were added at the rates of 2 and 4 g/kg to a fish-meal-based control diet, and each diet was given (twice daily [midmorning and midafternoon] to apparent satiation) to triplicate groups of gilthead seabream growers (mean weight = approximately 170 g) in sea cages. The trial lasted 12 weeks, and the average ambient water temperature ranged from 19.6°C to 24.7°C during the experimental period. At the end of the experiment, fish attained market size (350–450 g) and their health status was evaluated by blood analysis and liver histology. There were no differences in survival rates among fish fed experimental diets. However, there were significant improvements in both growth and feed utilization among fish fed diets supplemented with MOS. Hemoglobin (Hb) and hematocrit (Ht) levels and erythrocyte, leukocyte, and thrombocyte (Thr) counts were unaffected by any dietary MOS. The levels of Hb (g/dL; mean ± SD) and Ht (%; mean ± SD) were 11.0 ± 2.5 and 45.6 ± 6.7 for the control group, 11.1 ± 1.7 and 39.3 ± 8.0 for the 2-g/kg group, and 11.2 ± 1.9 and 40.2 ± 8.4 for the 4-g/kg group. The mean Thr count ranged from 47.6 to 53.8 × 103/mm3. Despite the apparently higher Thr counts for fish fed diets supplemented with MOS, these differences were not significant. Moreover, no histopathological differences were observed in liver tissue cross sections between control and treatment groups. These results suggest that supplementation of diets with MOS had no significant effects on general fish health.

Received February 20, 2011; accepted September 12, 2011  相似文献   
4.
This paper presents an application of high resolution satellite remote sensing data for mapping water quality in the Goldon Horn, Istanbul. It is an applied research emphasizing the present water quality conditions in this region for water quality parameters; secchi disc depth (SDD), chlorophyl-a (chl-a) and total suspended sediment (TSS) concentration. The study also examines the retrievals of these parameters through high resolution IKONOS multispectral data supported by in situ measurements. Image processing procedure involving radiometric correction is carried out for conversion from digital numbers (DNs) to spectral radiance to correlate water quality parameters and satellite data by using multiple regression technique. The retrieved and verified results show that the measured and estimated values of water quality parameters in good agreement (R 2?>?0.97). The spatial distribution maps are developed by using multiple regression algorithm belonging to water quality parameters. These maps present apparent spatial variations of selected parameters and inform the decision makers of water quality variations in a large water region in the Istanbul metropolitan area.  相似文献   
5.
A feeding trial was performed to assess the potential beneficial effect of two levels of mannanoligosaccarides (MOS) on the growth performance, feed utilization, hematological parameters, and liver histopathology of gilthead seabream Sparus auratus (also known as gilthead bream). Mannanoligosaccarides were added at the rates of 2 and 4 g/kg to a fish-meal-based control diet, and each diet was given (twice daily [midmorning and midafternoon] to apparent satiation) to triplicate groups of gilthead seabream growers (mean weight = approximately 170 g) in sea cages. The trial lasted 12 weeks, and the average ambient water temperature ranged from 19.6 degrees C to 24.7 degrees C during the experimental period. At the end of the experiment, fish attained market size (350-450 g) and their health status was evaluated by blood analysis and liver histology. There were no differences in survival rates among fish fed experimental diets. However, there were significant improvements in both growth and feed utilization among fish fed diets supplemented with MOS. Hemoglobin (Hb) and hematocrit (Ht) levels and erythrocyte, leukocyte, and thrombocyte (Thr) counts were unaffected by any dietary MOS. The levels of Hb (g/dL; mean +/- SD) and Ht (%; mean +/- SD) were 11.0 +/- 2.5 and 45.6 +/- 6.7 for the control group, 11.1 +/- 1.7 and 39.3 +/- 8.0 for the 2-g/kg group, and 11.2 +/- 1.9 and 40.2 +/- 8.4 for the 4-g/kg group. The mean Thr count ranged from 47.6 to 53.8 x 10(3)/mm3. Despite the apparently higher Thr counts for fish fed diets supplemented with MOS, these differences were not significant. Moreover, no histopathological differences were observed in liver tissue cross sections between control and treatment groups. These results suggest that supplementation of diets with MOS had no significant effects on general fish health.  相似文献   
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This study was carried out randomized complete blocks design with three replications during the growing seasons of 2010 and 2011 to compare the effects of conventional and organic production systems on yield, quality, and plant characteristics of Nantindo determinate carrot cultivar. In our study cow manure, sheep manure, poultry manure, seaweed, and conventional applications were made. As for average yield, the five-ton poultry manure application was the highest (5.91 t/ha?1) whereas control application was the lowest (3.37 t/ha?1). The widest root diameter, longest root length, the highest root weight, total soluble solids content, total sugar content, antioxidant activity were determined in different doses of poultry manure applications. A correlation between the examined quality and plant characteristics was determined. The other the most dry matter (11.80%), phenolic matter (188.98 mg.10?2g?1 GAE) and β carotene (205.95 µg.g?1) contents was determined in conventional application. The different doses poultry manure application on growth and yield of carrot were determined a positive effect.  相似文献   
7.
The main goal of this study was to investigate spatial patterns in water quality in Lake Beysehir, which is the largest freshwater reservoir in Turkey, by using Landsat-5TM (Thematic Mapper) data and ground surveys. Suspended sediment (SS), turbidity, Secchi disk depth (SDD), and chlorophyll-a (chl-a) data were collected from 40 sampling stations in August, 2006. Spatial patterns in these parameters were estimated using bivariate and multiple regression (MR) techniques based on Landsat-5TM multispectral data and water quality sampling data. Single TM bands, band ratios, and combinations of TM bands were estimated and correlated with the measured water quality parameters. The best regression models showed that the measured and estimated values of water quality parameters were in good agreement (0.60 < R 2 < 0.71). TM3 provided a significant relationship (R 2?=?0.67, p?<?0.0001) with SS concentration. MR between chl-a and various combinations of TM bands showed that TM1, TM2, and TM4 are strongly correlated with measured chl-a concentrations (R 2?=?0.60, p?<?0.0001). MR of turbidity showed that TM1, TM2, and TM3 explain 60% (p?<?0.0001) of the variance in turbidity. MR of SDD showed a strong relationship with measured SDD, with R 2?=?0.71 (p?<?0.0001) for the ratio TM1/TM3 and TM1 band combinations. The spatial distribution maps present apparent spatial variations of selected parameters for the study area covering the largest freshwater lake and drinking water reservoir in Turkey. Interpretation of thematic water quality maps indicated similar spatial distributions for SS, turbidity, and SDD. A large area in the middle portion of the lake showed very low chl-a concentrations as it is far from point and nonpoint sources of incoming nutrients. The trophic state index values were calculated from chl-a and SDD measurements. Lake Beysehir was classified as a mesotrophic or eutrophic lake according to chl-a or SDD parameters, respectively.  相似文献   
8.
Selenium (Se) is an essential micronutrient for humans and animals, and also affects plant metabolism. In this study, the effects of increasing doses of Se application on the uptake of selenium (Se), nitrogen (N), and sulfur (S) content of three barley cultivars were investigated. The analysis indicated that the Se contents were highest in root tissues, intermediate in grain, and lowest in stem tissues in all cultivars. Total Se accumulations (whole plant) were highest in ‘Bülbül 89’ (0.171 mg kg?1), intermediate in ‘Çetin 2000’ (0.153 mg kg?1), and lowest in ‘Tarm 92’ cultivars (0.124 mg kg?1). In all cultivars, the increase in grain Se content resulted in a decrease in the grain N content. While ‘Bülbül 89’ can be suggested for biofortification purposes, less Se accumulating ‘Tarm 92’ cultivar can be suggested as a fodder in Se contaminated or high Se containing areas.  相似文献   
9.
Roemeria hybrida yielded two novel proaporphine-tryptamine N-oxides, (-)-roehybridine alpha-N-oxide (1) and (-)-roehybramine beta-N-oxide (2). NMR data allowed a facile assignment of these proaporphine-tryptamine dimers into different stereochemical subgroups.  相似文献   
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