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381.
Comparative acute toxicity studies of the latex and sequential extracts of Leptadenia pyrotechnica (Forsk.) Decne (Asclepiadaceae) were recorded using brine shrimp. The higher toxicities were exhibited in latex; methanol, methanol/dichloromethane (1:1), defatted methanol/dichloromethane (1:1), defatted methanol and dichloromethane extracts. The other extracts; aqueous, alkaloids, ethyl acetate and n-butanol exhibited less toxicities compared with the other extracts. The estimated LC50 and its 95% confidence limits for these extracts expressed in ppm were: methanol, latex 18.84 (11.22-31.61), methanol/dichloromethane 19.95 (7.76-53.70), defatted methanol/dichloromethane 21.38 (7.24-63.10), defatted methanol 28.19 (16.27-48.81) and dichloromethane 30.90 (11.75-79.43). The anti-tumor activities; potato disc assays of methanol, ethyl acetate and alkaloids extracts showed good activities as anti-tumor agent which represented-49.30,-43.20 an -33.60%, respectively. While latex and aqueous extract represented-30.80 and-28.17%, respectively. 相似文献
382.
Abu-Samak M Yousef AM Al-Jarie A Al-Matubsi HY Abu-Zaiton A Al-Quraan M Khuzaie R 《Pakistan journal of biological sciences: PJBS》2011,14(5):344-350
To analyze the influence ofhyperleptinemia on fasting lipid and hematological parameters in healthy Arab male youth in Jordan, this cross-sectional study was carried out in April 2009 on a sample of 120 students aged 18-24 years. Subjects were stratified by fasting leptin into two groups (control, <12.7 ng mL(-1) vs. hyperleptenimic, e_< 12.7 ng mL(-1)) and BMI (normal weight, < 25 kgm(-2) vs. overweight/obese, BMI e_< 25 kg m(-2)). Fasting serum leptin, blood glucose, lipid profile and hematological parameters values were determined by standard kit methods. Mean serum leptin concentrations were more than five times as high in hyperleptenemic subjects than in control subjects (p < 0.001). Compared with control group, significant elevations (p < 0.01) were observed in the means total cholesterol, LDL cholesterol and triglyceride levels of hyperleptenemic group whereas no significant differences was detected in HDL-cholesterol. Except the changes of WBC count, MCH and slightly MCHC, there were no differences between both groups in any other term of hematological parameters. In conclusion, changes in lipid variables and some hematological parameters may increase plasma viscosity as a step during atherosclerosis pathogenesis in male youth at risk for dyslipidemia and cardiovascular diseases. Thus, hyperleptinemia could be a useful index in identifying healthy youth male subjects but this hypothesis needs further investigation. 相似文献
383.
Mahmoud A. Hamza Professor Ahmed M. El-Tabey Shehata Hermann Stegemann 《Plant foods for human nutrition (Dordrecht, Netherlands)》1987,36(4):253-262
A number of national dishes are prepared from the dry seeds of faba bean by soaking, germination (nabet), cooking (bisara and medammis) or frying a dough (falafel). Soaking (12 h) decreased the intensity of bands in the standard PAGE and increased the charge heterogeneity of neutral proteins in PAGIF. Germination (24 or 60 h) changed the patterns for esterases, peroxidases and amylases, but not for phosphorylases. The charge distribution of proteins was markedly changed in the basic region. Roasting did not affect the distribution in standard PAGE. All bands in the basic region of PAGIF disappeared. High MW-proteins wre degraded to low MW-proteins as seen in SDS-PAGE. The cooking broth and the cooked beans of nabet soup and medammis had more or less similar patterns in the standard PAGE. The broth of nabet soup had larger number of low MW-proteins than the bean extract in SDS-PAGE. Bisara proteins showed almost the same patterns as the corresponding proteins of the cooking broth of nabet soup. Falafel proteins showed patterns very similar to that obtained from roasted beans in the SDS-PAGE. PAGIF gave a different but characteristic charge distribution for falafel. 相似文献
384.
Khalil Mohamed Salah Abd El-Aziz Mahmoud Hamdy Selim Rasha El-Sayed 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):799-812
European Journal of Plant Pathology - Root-knot nematodes (Meloidogyne spp.) have been reported to be responsible for large economic losses of agricultural crops due to their wide host range and... 相似文献
385.
Krishnan HB Natarajan SS Mahmoud AA Bennett JO Krishnan AH Prasad BN 《Journal of agricultural and food chemistry》2006,54(15):5489-5497
Soybeans contain approximately 40% protein and 20% oil and represents an important source of protein in animal rations and human diets. Attempts are being made to increase further the overall protein content of soybeans by utilization of exotic germplasms. In this study, soybean cultivars from Nepal have been characterized and their potential as a germplasm resource for improvement of the protein content and quality of North American cultivars assessed. Soybean cultivars 'Sathia', 'Seti', 'Kavre', and 'Soida Chiny', indigenous to various regions of Nepal, contained 42-45% protein, which is significantly higher in comparison to that of the North American cultivar 'Williams 82' (39%). Fractionation of seed protein by high-resolution two-dimensional gel electrophoresis revealed differences in the protein profiles of these cultivars. Various isoelectric forms of glycinin and beta-conglycinin were identified by comparing the matrix-assisted laser desorption ionization time-of-flight mass fingerprinting data against the National Center for Biotechnology Information nonredundant database. Nepalese cultivar Sathia was distinct, lacking some isoelectric forms of acidic and basic glycinin subunits while expressing other unique forms. The contribution of these unique protein spots present in either Sathia or Williams 82 to the total protein content was quantified using scanning laser densitometry. Distinct restriction fragment length polymorphisms (RFLP) for group 1 glycinin genes were observed among the tested Nepalese genotypes, indicating sequence variation among the cultivars. Conversely, evaluation of RFLP for the genes encoding group 2 glycinins, beta-conglycinin, and Bowman-Birk proteinase inhibitors indicated a high degree of conservation in these genes. Determination of amino acid composition, a reflection of protein quality, indicated that the arginine content of the Nepalese soybeans ranged from 7.7 to 8.1%, which was 5-10% higher than the 7.4% expressed in Williams 82. Additionally, Karve and Seti contained significantly more cysteine than Williams 82. Nepalese high-protein soybeans having a desirable amino acid composition hold potential to increase the protein quality and diversity of North American cultivars. 相似文献
386.
Supplementation of diets for Oreochromis niloticus with essential oil extracts from lemongrass (Cymbopogon citratus) and geranium (Pelargonium graveolens) and effects on growth,intestinal microbiota,antioxidant and immune activities 下载免费PDF全文
A. A. Al‐Sagheer H. K. Mahmoud F. M. Reda S. A. Mahgoub M. S. Ayyat 《Aquaculture Nutrition》2018,24(3):1006-1014
This study aimed to investigate the effects of dietary supplementation of lemongrass (Cymbopogon citratus) (LEO) and geranium (Pelargonium graveolens) (GEO) essential oils on growth, immunity, antioxidant responses and disease resistance of Oreochromis niloticus. Fish (3.04 ± 0.003 g) were fed the basal diet (G1), or the basal diet supplemented with LEO at 200 and 400 mg kg?1 of the diet (G2 and G3), or GEO at 200 and 400 mg kg?1 of the diet (G4 and G5), respectively for 12 weeks. Growth indices and feed utilization were significantly improved with G2, G3 and G5 groups. Also, a significant increase in protein content of the whole body was recorded in all groups. G2 and G5 showed a significant rise of both catalase activity and reduced glutathione content with a significant incline in the MDA level. Lysozyme activity and total IgM levels were significantly increased in G2 and G5 groups. G3 and G5 groups had a significantly lower intestinal total bacteria, Coliforms, Escherichia coli and Aeromonas spp counts. Following challenge with A. hydrophila, all groups had a high survival rate. In conclusion, LEO and GEO could be a candidate dietary supplementation in fish improving growth performance, feed utilization, oxidative status, immune responses and disease resistance. 相似文献
387.
Mahmoud Nafisi Bahabadi Mansour Torfi Mozanzadeh Naser Agh Ali Ahmadi Morteza Yaghoubi 《Journal Of Applied Aquaculture》2018,30(4):325-336
A 15-day study was conducted to evaluate the effect of enrichment of Artemia metanauplii with four different emulsions, including: (A) Easy-DHA Selco; (B) Easy-DHA Selco + L-lysine (4 g/L); (C) Easy-DHA Selco + DL-methionine (4 g/L); and (D) Easy-DHA Selco + L-lysine (2 g/L) + DL-methionine (2 g/L) on growth and stress resistance of white leg shrimp Litopenaeus vannamei larvae (from Mysis I to postlarvae12). It is noticed that shrimp PL in group B had the highest wet (36.1 ± 3.1 mg) and dry (1116.7 ± 60.0 µg) weights as well as stress resistance to fresh water (64.0 ± 5.5%). 相似文献
388.
Yasser Mahmoud Awad Johanna Pausch Yong Sik Ok Yakov Kuzyakov 《Journal of Soils and Sediments》2017,17(3):621-631
Purpose
The applications of biochar (BC) and polyacrylamide (PAM) may have interactive effects on carbon (C) dynamics and sequestration for improving the soil quality and achieving sustainable agriculture. Relative to BC and PAM, rhizodeposits act as C and energy source for microorganisms and may change the mineralization dynamics of soil organic matter (SOM). No attempt has been made to assess the effects of BC, anionic PAM, or their combination on the decomposition of different aged 14C-labeled rhizodeposits. The objective of this study was to investigate the effects of the treatments mentioned above on the decomposition of different aged 14C-labeled maize rhizodeposits.Materials and methods
biochar (BC) at 10 Mg ha?1 or anionic PAM at 80 kg ha?1 or their combination (BC + PAM) was applied to soils with/without 2-, 4-, 8-, and 16-day-aged 14C-labeled maize rhizodeposits. After that, the soil was incubated at 22 °C for 46 days.Results and discussion
After 2 days of incubation, the total CO2 efflux rates from the soil with rhizodeposits were 1.4–1.8 times higher than those from the soil without rhizodeposits. The cumulative 14CO2 efflux (32 % of the 14C input) was maximal for the soil containing 2-day-aged 14C-labeled rhizodeposits. Consequently, 2-day-aged rhizodeposits were more easily and rapidly decomposed than the older rhizodeposits. However, no differences in the total respired 14CO2 from rhizodeposits were observed at the end of the incubation. Incorporation of 14C into microbial biomass and 66–85 % of the 14C input remained in the soil after 46 days indicated that neither the age of 14C-labeled rhizodeposits nor BC, PAM, or BC + PAM changed microbial utilization of rhizodeposits.Conclusions
Applying BC or BC + PAM to soil exerted only minor effects on the decomposition of rhizodeposits. The contribution of rhizodeposits to CO2 efflux from soil and MBC depends on their age as young rhizodeposits contain more labile C, which is easily available for microbial uptake and utilization.389.
Mohamed Abdo Rizk Motamed Elsayed Mahmoud Shimaa Abd El-Salam El-Sayed Doaa Salman 《Tropical animal health and production》2017,49(8):1723-1731
In the current study, we compared the therapeutic effects of a non-steroidal and a steroidal anti-inflammatory drug on the production of pro-inflammatory cytokines, interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-12p40 (IL-12p40), interferon gamma (IFNγ), and tumor necrosis factor alpha (TNF-α) in the blood of water buffalo (Bubalus bubalis) calves naturally infected by bronchopneumonia. Twenty-seven buffalo calves (7 ± 2-month-old, 163 ± 12 kg) reared in smallholder farms in El-Dakahlia province in Egypt were identified to have bronchopneumonia and randomly allocated into three equal groups. Ten clinically healthy buffalo calves with negative bronchoalveolar lavage results were served as negative control. Diseased calves were treated with tulathromycin alone, a combination of tulathromycin with dexamethasone (steroidal anti-inflammatory drug) or tulathromycin with flunixin meglumine (non-steroidal anti-inflammatory drug). The results revealed significant elevations (P < 0.05) in the production of selected cytokines in all diseased calves in comparison with healthy animals. Six days post-treatment, a significant inhibition (P < 0.05) in the production of all assessed cytokines was observed in the blood of all treated calves. Interestingly, the serum concentrations of IL-1β and IL-12p40 were returned to the normal levels in pneumonic calves treated with the combination therapy of tulathromycin and flunixin meglumine. A strong significant positive correlation (P < 0.05) was detected between clinical sum scoring and IL-12p40 and TNF-α concentrations. The obtained results indicate the selectively potent anti-inflammatory effect of flunixin meglumine on the production of pro-inflammatory cytokines in pneumonic buffalo calves and highlight the efficacy of flunixin meglumine in the treatment of bronchopneumonia in buffalo calves when used in combination with tulathromycin. 相似文献
390.
Alaa Ibrahim Adel Rabie Ahmed Usman Mohammad Ibrahim Al-Wabel Mahmoud Nadeem Yong Sik Ok 《Archives of Agronomy and Soil Science》2017,63(2):185-197
A laboratory column experiment was conducted to investigate the effects of 400°C biochar at application rate of 15 g kg?1 (21.9 t ha?1) with different particle sizes (<0.5 mm (S1), 0.5–1 mm (S2) and 1–2 mm (S3)) and application depths (0–2 cm depth (D0), 4–6 cm depth (D5) and 8–10 cm depth (D10)) on hydro-physical properties of sandy loam soil. The results indicated that applying biochar decreased the waterfront and saturated hydraulic conductivity of sandy loam soil. The cumulative evaporation was the highest and amounted to 40.9 mm in the non-treated soil, but it recorded the lowest amount of 32.2–35.5 mm in the biochar-treated soil. Applying biochar caused significant increases in the amount of conserved and retained water with the highest amount of water conserved in soil treated with S2 biochar at D5. Moreover, the cumulative water infiltration through the soil was significantly reduced by S1 and S2 biochars at D0. The values of saturated hydraulic conductivity for biochar treatments were significantly lower than those for the control, with the lowest values for S1 at D0 and D5. These results suggest positive improvement for the hydro-properties of coarse-textured soils following biochar addition, especially with finer particles of biochar. 相似文献