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71.
İlhami Gülçin Riad Elias Akçahan Gepdiremen Khalil Taoubi Ekrem Köksal 《Wood Science and Technology》2009,43(3-4):195-212
Recently, a number of studies on health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. The fringe tree (Chionanthus virginicus) is used as a raw material by pharmaceutical industries for the preparation of homeopathy tinctures. The potential antioxidant activities of two secoiridoids from root bark of fringe tree (Chionanthus virginicus L.) were investigated to evaluate their potential value as the natural products for foods or cosmetic applications. In this study, antioxidant activities were measured by 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, superoxide anion (O 2 ·? ) radical scavenging, total antioxidant activity, reducing activity, hydrogen peroxide (H2O2) scavenging and ferrous metal chelating activity assays. These secoiridoids, as antioxidants neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. Total antioxidant activity was measured according to ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analog of tocopherol, were used as the reference antioxidant compounds. Ligustroside (3.70 × 10?3 M) and oleuropein (3.80 × 10?3 M) showed 71.9, 82.4, 80.7 and 90.4% inhibition on lipid peroxidation of linoleic acid emulsion, at the concentrations of 10 and 20 μg/mL. On the other hand, 20 μg/mL of standard antioxidant such as α-tocopherol (4.64 × 10?3 M), trolox (7.98 × 10?3 M), BHA (10.08 × 10?3 M) and BHT (9.06 × 10?3 M) exhibited 61.5, 29.8, 74.4 and 71.2% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, ligustroside and oleuropein had effective DPPH·, ABTS·+ and superoxide anion radicals scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to BHA and BHT, α-tocopherol and trolox that are references antioxidants. 相似文献
72.
Shimaa M. Abou-Zeid Samira H. Aljuaydi Huda O. AbuBakr Enas A. Tahoun Alessandro Di Cerbo Mahmoud Alagawany Samah R. Khalil Mayada R. Farag 《Marine drugs》2021,19(9)
Thiacloprid (TCP) is a widely used neonicotinoid insecticide with a probable toxic hazard to animals and human beings. This hazard has intensified the demand for natural compounds to alleviate the expected toxic insults. This study aimed at determining whether astaxanthin (ASX) could mitigate the hepatotoxic effect of TCP and diminish its suppressive effect on immune responses in rats. Animals received TCP by gavage at 62.1 mg/kg (1/10th LD50) with or without ASX at 40 mg/kg for 60 days. Intoxicated rats showed modulation of serum transaminases and protein profiles. The hemagglutination antibody titer to sheep red blood cells (SRBC) and the number of plaque-forming cells in the spleen were reduced. The cell-mediated immunity and phagocytosis were suppressed, while serum interleukins IL-1β, IL-6, and IL-10 were elevated. Additionally, malondialdehyde, nitric oxide, and 8-hydroxy-2′-deoxyguanosine levels were increased in the liver, spleen, and thymus, with depletion of glutathione and suppression of superoxide dismutase and catalase activities. The expressions of inducible nitric oxide synthase and the high mobility group box protein 1 genes were upregulated with histomorphological alterations in the aforementioned organs. Cotreatment with ASX markedly ameliorated the toxic effects of TCP, and all markers showed a regression trend towards control values. Collectively, our data suggest that the protective effects of ASX on the liver and immune system of TCP-treated animals depend upon improving the antioxidant status and relieving the inflammatory response, and thus it may be used as a promising therapeutic agent to provide superior hepato- and immunoprotection. 相似文献
73.
TM El‐sherry MA Abdel‐Ghani NS Abou‐Khalil M Elsayed M Abdelgawad 《Reproduction in domestic animals》2017,52(5):781-790
The aim of the present research is to study the effect of pH values on the sperm rheotaxis properties. Semen collected from bulls was diluted with SOF medium (1:10). pH of the medium was adjusted using a digital pH meter to the following pH values: 6.0, 6.2, 6.4, 6.4, 6.8, 7.0. All kinetic parameters of sperm (n = 3,385) were determined through a computer‐assisted sperm analysis (CASA) system using microfluidic devices with controlled flow velocity. The following parameters were determined: total motility (TM%), positive rheotaxis (PR%), straightline velocity (VSL, μm/s), average path velocity (VAP, μm/s), linearity (LIN, as VSL/VCL, %), beat cross‐frequency (BCF, Hz) and curvilinear velocity (VCL, μm/s). Nitric oxide, calcium and potassium were estimated in semen at different pH values. To confirm the effect of nitric oxide and K+, we used sodium nitroprusside (an NO donor) and KCL as (a K+ donor) to see their effect on sperm PR%. The results showed no difference in TM% at pH (6–7). The PR% was the lowest at pH 6 and 7. The best parameters for the PR% were at pH 6.4–6.6. The concentration of Ca+2 did not change at different pH values. The mean NO values decreased with the increase of pH; however, the mean values of K+ increased with the increase of pH. Addition of high concentration of NO and K+ to the semen media at fixed pH level had a negative effect on TM% and PR%. In conclusion, the bull sperm had the best rheotaxis properties at pH 6.4–6.6 and sensitive to the change of seminal NO and K+. 相似文献
74.
Due to its unique historical and geographical emplacement, grapes have been cultivated in the Syrian Arab Republic for more than 5000 years, so the characterization of its local genetic resources is paramount for understanding grapevine natural diversity. In this work, different local Syrian table grape cultivars were characterized for 42 traits related to plant phenology, shoot, leaf, cluster, berry and juice composition. A series of multivariate analyses were sequentially performed, and five highly-discriminant traits were identified as the most discriminant ones (shoot internode length, berry weight, berry elongation, 100-seed weight and juice titratable acidity). The clustering of the cultivars according to these five traits revealed that some local Syrian cultivars share similitude with some worldwide grown cultivars, suggesting their potential as new genetic resources for the development of new high-quality table grape varieties, and indicating the needing of specific preservation programs aimed to avoid the loss of endangered genetic local resources. Besides, the statistical multivariate pipeline followed in this work is proposed as an efficient one for the selection of ampelographic traits for the discrimination of grapevine cultivars. 相似文献
75.
76.
Vronique S. Lesage Brigitte Bouchet Larbi Rhazi Khalil Elmorjani Grard Branlard Didier Marion 《Journal of Cereal Science》2011,53(2):231-238
Wheat endosperm texture is correlated with one major locus, Ha, located on the short arm of chromosome 5D, which comprises several genes among which are two puroindoline genes, Pina and Pinb. In this study, we used two near-isogenic lines, the hard-textured line lacking Pina and the soft-textured line containing both Pina and Pinb wild-type genes. Hard and soft endosperms were observed at four kernel developmental stages, from 180 °Cd to 750 °Cd. Puroindolines were located within protein bodies at the onset of prolamin accumulation by transmission electron microscopy and immunolabelling. Ab initio modeling showed a closer structural relationship between puroindolines and 2S storage proteins from dicots than between puroindolines and other cysteine-rich wheat proteins, i.e. LTP and amylase inhibitors. Compared to the soft line, storage protein polymers in the hard line exhibited higher molecular mass (increase of from 6 to 93%) and polydispersity indices (increase of from 26 to 63%) over the course of the 4-year experiment. This suggests that puroindolines might impact the aggregation of storage proteins. Finally, these data pave the way for investigation of the role of protein–protein interactions in the texture of wheat endosperm. 相似文献
77.
Journal of Plant Diseases and Protection - The effect of the bacterial strain Pseudomonas fluorescens 5.014 together with three commercial biocontrol products (Binab T, Gliomix and Mycostop)... 相似文献
78.
Native glutenin aggregates of two different quality flours containing the same high molecular weight (HMW) glutenin subunit compositions were investigated by multistacking sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) procedures. Five stacking gels (4, 6, 8, 10, and 12%) with a separating (resolving) gel of 14% were used to separate nonreduced glutenin aggregates solubilized from flour by SDS sodium phosphate buffer. There were large differences in protein solubility of the two flours. It took 8 hr to extract 91% of total proteins from the strong flour (variety Len) while it took only 2 hr for the weak flour sample 205. Total glutenin proteins and the proportions of glutenins at the different origins (including the origin of the 14% separating gel) were quantified by high-resolution densitometry procedures. As the duration of extraction increased, both total glutenins and glutenins at the 4% origins increased. The good quality flour Len had a higher total glutenin protein (3% more) and higher proportion of glutenins with the largest molecular sizes (also 3% more) at the 4% origins than the poor quality flour sample 205. After glutenin aggregates from each origin were reduced and analyzed by SDS-PAGE, the largest glutenins at the 4% origin contained twice the amount of total HMW glutenin subunits when compared to the smaller aggregates at the 12% origin. Among the total HMW glutenin subunits, the proportion of subunit 5 (which published literature reports to be the largest molecular weight based on calculations of DNA-derived amino acid sequence analysis) was twice that at the 12% origin. A randomized structure of native glutenins is proposed based on the results of our investigations. 相似文献
79.
Partial purification and characterization of a protein in porcine follicular fluid which restricts sperm-egg interaction in vitro.
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An attempt was made to isolate and characterize a component in preovulatory porcine follicular fluid (pFF) which has a restricting effect on sperm-egg interaction in vitro. Using the zona-free hamster ova (eggs) penetration assay as an in vitro test system, it was shown previously that the numbers of porcine spermatozoa attached to or penetrated into each egg and the number of eggs with sperm attached or penetrated decreased significantly as the concentration of pFF was increased in the culture medium. In the present study, the component in pFF having these effects was shown to be a heat stable, nonsteroidal substance which retained its activity after dialysis, lyophilization and gel filtration chromatography. The activity was also found to be present in preovulatory homologous serum. Separation of the material on protein type gel filtration columns with detection at 280 nm, together with the banding seen with Coomassie staining on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), suggests that it is a protein. Based on high pressure liquid chromatographic separation (HPLC) and SDS-PAGE analyses, the bioactivity could be due to a single protein of 87 kD or to one or more of three smaller proteins, possibly disaggregated products of the 87 kD protein, in the range of 26-28 kD. 相似文献
80.