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301.
Phytochemical investigation of Beilschmiedia alloiophylla has resulted in the isolation of one new alkaloid, 2-hydroxy-9-methoxyaporphine (1), and ten known natural products, laurotetanine (2), liriodenine (3), boldine (4), secoboldine (5), isoboldine (6), asimilobine (7), oreobeiline (8), 6-epioreobeiline (9), β-amyrone (10), and (S)-3-methoxynordomesticine (11). Chemical studies on the bark of B. kunstleri afforded compounds 2 and 4 along with one bisbenzylisoquinoline alkaloid, N-dimethylphyllocryptine (12). Structures of compounds 1-12 were elucidated on the basis of spectroscopic methods. All of these isolates were evaluated for their anti-acetylcholinesterase (AChE), anti-α-glucosidase, anti-leishmanial and anti-fungal activities. Compounds 1-12 exhibited strong to moderate bioactivities in aforementioned bioassays.  相似文献   
302.
In this study, the effect of spirulina meal (Spirulina platensis) as a feed additive on growth and physiological response of Oscar fish,Astronotus ocellatus, was assessed using four diets including control without spirulina supplementation, 13.75 g/kg spirulina (SP1), 27.50 g/kg spirulina (SP2) and 55 g/kg spirulina (SP3). One hundred and twenty fish (10.41 ± 0.25 g) were disturbed to twelve aquariums and fed to apparent satiation three times a day for 8 weeks. The result showed that the SP3 treatment had statistically better growth performance, feeding parameters, total protease activity, total protein and lipid contents than the control. Moreover, haemoglobin, haematocrit, mean erythrocyte haemoglobin and mean erythrocyte haemoglobin concentrations were improved considerably in the SP3 treatment compared with the control. The SP3 treatment showed higher total protein and albumin levels, but lower triglycerides, cholesterol levels and liver enzyme activities than the control. Also, serum complements (C3, C4), lysozyme activity and total carotenoid contents in fish skin significantly increased in the SP3 treatment compared with the control. The results of this study suggest that spirulina powder at the level of 55 g/kg of the diet can be used as a functional natural feed additive to improve the performance of Oscar fish.  相似文献   
303.
This study evaluated the potential of glauconitic sandstone as a fertilizer for supplying potassium to plants. The glauconite sandstone (Maraveh, Iran), as analyzed by X-ray fluorescence, was composed of 2.24% potassium oxide plus high contents of silicon, aluminum and ferric oxide. One-year old olive trees, Olea europaea L., were grown in sand or hydroponic culture in a greenhouse under three potassium treatments. Modified Hoagland nutrient solutions based on potassium treatments including 0.5 mM K+, 5 mM K+ and 400 g glauconitic sandstone powders (per 10 L in hydroponics and per 2.5 L in sand instead of K+ supply) were used in both cultures. Plants grown under the three different potassium treatments did not show any potassium deficiency symptoms. In the sand culture, growth and potassium content were higher in plants fed with 5 mM potassium than with the other two potassium treatments. Growth retardation and decreased potassium content in plants fed with 0.5 mM potassium were more severe in the hydroponic culture than in the sand culture. However, plants fed with 400 g glauconitic sandstone showed higher growth in the hydroponic culture than the sand culture. Thus, glauconitic sandstone has the ability to release potassium and can be utilized in combination with other potassium fertilizers.  相似文献   
304.
A study was made in the net house of Plant Physiology, Department of Botany, Aligarh Muslim University, Aligarh to study the comparative effect of wastewater and groundwater along with three different rates of nitrogen (N) of 0, 30, and 60 kg ha?1 on growth, physiology and yield of two varieties of chilli cv. ‘G4’ and ‘Pusa Jawala’. Wastewater irrigation resulted significant increase in shoot and root length, fresh weight, dry weight, leaf number and area, net photosynthetic rate (PN), stomatal conductance (gs), water use efficiency (WUE), chlorophyll content, and yield. The physio-chemical parameters of wastewater met the irrigational characteristics, being well within the permissible limit as outlined by the Food and Agriculture Organization. Among the nitrogen doses 30 kg ha?1 N along with wastewater proved best for the growth and yield. Thus it may be concluded that wastewater reduced the demand of fertilizers and it may be used for the cultivation of chilli.  相似文献   
305.
N-alkanes were measured both in dissolved and particulate-adsorbed phases of water samples collected from five stations located along Shatt al-Arab River in Iraq. The aim of this study was to provide a background information on the presence, origin, and distribution of n-alkanes in the waters of Shatt al-Arab River. Total concentrations of n-alkanes were lower in the dissolved phase (29.37 (μg L?1) than in the particulate-adsorbed fraction (17.62 μg g?1 dw). Distribution of n-alkanes in both fractions is characterized by two distinct patterns. First, for C compounds numbered C14 to C22, the ‘odd’ numbered hydrocarbons were slightly more abundant with C17 being the most concentrated. The second is shown within n-alkanes greater than C22. In these the ‘odd’ numbered hydrocarbons show even greater predominance indicating that much of the n-alkanes in the waters of Shatt al-Arab, may have originated from aquatic biogenic sources; i.e., diatoms, algal forms, bacterial activities, and higher plants. The CPI values were found to be from 0.99 to 1.98 in the dissolved fraction and from 0.70 to 2.10 in the particulate fraction. Petroleum hydrocarbon inputs and urban related oil discharges (anthropogenic pollution) may also have contributed to the input of n-alkanes in Shatt al-Arab, particularly near the city of Basrah (St. IV). Total concentrations at station IV were much higher (8.40 μg L?1 and 5.80 μg g?1) than that for the most upstream station, # I, (3.20 μg L?1 and 1.48 μg g?1) and decreased again further downstream at station V (7.10 μg L?1 and 4.32 μg g?1). The CPI values were around 1.0 in station IV. In a conclusion, results obtained in this study indicate that the n-alkanes in the waters of Shatt al-Arab River are of aquatic biogenic and anthropogenic (petroleum related) origins.  相似文献   
306.
Summary The uptake of labelled and unlabelled N by wheat was measured in a field experiment using 15N-labelled ammonium nitrate fertilizer. The dry matter yield and N yields were significantly increased with fertilizer N application compared to those from unfertilized soil. The uptake of applied N by wheat ranged between 25 and 34%. Fertilizer N application increased the uptake of unlabelled soil N which was attributed to a positive priming effect or added N interaction. The added N interaction observed by applying 20, 60, and 120 kg fertilizer N was 11.4, 19.1, and 27.9 kg, corresponding to 26, 44 and 64%, respectively of the N taken up from unfertilized soil. The A values did not alter with the increase in fertilizer N application. The observed added N interaction may have been the result of pool substitution whereby added labelled fertilizer N stood proxy for unlabelled soil N. A significant correlation coefficient (r=0.996**) between the uptake of soil N and the dry matter yield showed that soil N was more important than fertilizer N in wheat production.  相似文献   
307.
Patulin, a toxic fungal metabolite, negatively affects rumen fermentation. This mycotoxin has also been associated with intoxication cases in cattle. This study investigates the use of SH-containing reducing compounds to prevent patulin's negative effects on the rumen microbial ecosystem. The effect of 50 microg/mL patulin on the fermentation of alfalfa hay was measured in batch cultures with and without reducing agents. Sulfhydryl-containing cysteine and glutathione prevented the negative effects of the toxin on dry matter degradation, gas, and volatile fatty acid production (P < 0.01). However, non-sulfhydryl-containing ascorbic and ferulic acids did not protect against patulin's toxicity (P > 0.01). Patulin was unstable in buffered rumen fluid as the concentration decreased by half after 4 h of incubation. In the presence of sulfhydryl groups, the toxin disappeared rapidly and was not detected after 1 h of incubation. The utilization of sulfhydryl-containing compounds such as cysteine to avert patulin toxicity could have practical implications in ruminant nutrition.  相似文献   
308.
The Indian crested porcupine (Hystrix indica) (ICP) is widely distributed in Asia; however, compared with other rodents, little is known about the structures of its respiratory system. The aim of this study was to evaluate the histomorphology of the lower respiratory portion of the ICP to provide a basis for the identification of the normal structure of this organ. The larynx, trachea and lungs of four carcasses of adult Indian crested porcupines (two males and two females) were dissected and fixed in 10% neutral-buffered formalin. The gross anatomy and histology of all specimens were evaluated. A macroscopic evaluation showed unique structures in the ICP respiratory system, including the presence of a chamber-like structure at the origin of the bronchi and a difference in epiglottis shape between males and females. Histologically, the stratified squamous epithelium covered the epiglottis and arytenoid cartilage, and the pseudostratified ciliated columnar epithelium covered the internal part of the thyroid and cricoid cartilages. Histomorphological studies showed a few goblet cells in the tracheal epithelium. In the bronchi and larger bronchioles, pseudostratified ciliated columnar epithelia were observed. Bronchi were surrounded by segments of cartilage. Distal bronchioles had a simple cuboidal/columnar epithelium with club (Clara) cells, lacked cartilaginous tissue in their walls and had a complete smooth muscle layer. These results revealed histomorphological differences between the ICP and other rodents.  相似文献   
309.
Cornelian cherry (Cornus mas L.) is a naturally growing dogwood species in Arasbaran (East Azerbaijan, Iran). Antioxidant capacity, total anthocyanins, total phenols, ascorbic acid and total flavnoids of a number of selected cornelian cherry genotypes were investigated. The total phenolic and antioxidant activity of methanol extract of cornelian cherry fruits were determined according to Folin–Ciocalteu and DPPH method, respectively. The range of ascorbic acid content of genotypes was 183.25–299.5 mg/100 g fresh weight (FW). Genotype C24 had the highest total antioxidant capacity (82.37) and total phenolic (2695.75 mg galic acid per 100 g FW basis). The highest total anthocyanin was observed in C27 genotype (442.11 mg cyanidin-3-glucoside equivalents/100 g FW). This genotype also had the highest total flavonoid (669 mg catechin per 100 g FW basis). There are linear relationships between the antioxidant capacities with total phenols, total flavonoid and ascorbic acid. But, No statistically significant correlation was observed between antioxidant activity and total anthocyanins. According to Path analysis, the highest direct effect on antioxidant was observed in total flavonoid (0.38). The present study demonstrates the potential of certain cornelian cherry genotypes, notably C24 and C27, for improvement of nutritional value through germplasm enhancement programs.  相似文献   
310.
Tropical Animal Health and Production - The aim of this study was to determine the optimum carcass weight for meat quality and fatty acid composition in fat-tailed Chall lambs. Thirty lambs (15...  相似文献   
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