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31.
Context: Cypermethrin (CYP) is a synthetic pyrethroid insecticide used worldwide in agriculture, home pest control. The toxicity of CYP is well studied in many organisms.

Objective: The aim of present study was to investigate the protective effect of Zizyphus lotus (Zizyp) fruit against neurotoxicity and oxidative stress induced by CYP in mice.

Materials and methods: Mice were divided into four groups of six each: groups I and II were used as control and CYP control (20?mg/kg body weight). While, groups III was orally treated with Zizyphus lotus fruit (5?g/kg body weight) plus CYP (20?mg/kg body weight) for 18?days. Furthermore, HPLC–ESI–MS–MS (Q-Tof) and GC–MS were used to identify the compounds fraction.

Results: Antioxidant enzyme catalase (CAT), neurotoxicity enzyme acetylcholinesterase (AChE) activities and hydrogen peroxide (H2O2), malondialdehyde (MDA) levels were determined in the liver, kidney and heart. CYP caused decreased CAT activity, inhibition of AChE activity and increased the levels of H2O2 and MDA in heart, liver and kidney.

Conclusion: Our results indicate that Zizyp fruit is markedly effective in protecting mice against CYP-induced biochemical changes. This protection may be due to its antioxidant property and scavenging ability against active free radicals.  相似文献   
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Pistacia lentiscus L. seed oil is used in some Mediterranean forest area for culinary and medicinal purposes. In this study, we aim to examine, for the first time, the effect of growing area on sterol content of Pistacia lentiscus seed oil. Fruits were harvested from 13 different sites located in northern and central Tunisia. Gas chromatography‐flame‐ionization detection (GC‐FID) was used to quantify sterols and gas chromatography/mass spectrometry (GC/MS) was used to identify them. The major sterol identified was β‐sitosterol with a value ranging from 854.12 to 1224.09 mg/kg of oil, thus making up more than 54% of the total sterols. The other two main sterols were cycloartenol (11%) and 24‐methylene‐cycloartenol (5%). Statistical results revealed that growing location significantly (< 0.001) affected phytosterol levels in these oils.  相似文献   
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The Geodermatophilaceae are unique model systems to study the ability to thrive on or within stones and their proteogenomes (referring to the whole protein arsenal encoded by the genome) could provide important insight into their adaptation mechanisms. Here we report the detailed comparative genome analysis of Blastococcus saxobsidens (Bs), Modestobacter marinus (Mm) and Geodermatophilus obscurus (Go) isolated respectively from the interior and the surface of calcarenite stones and from desert sandy soils. The genome-scale analysis of Bs, Mm and Go illustrates how adaptation to these niches can be achieved through various strategies including ‘molecular tinkering/opportunism'' as shown by the high proportion of lost, duplicated or horizontally transferred genes and ORFans. Using high-throughput discovery proteomics, the three proteomes under unstressed conditions were analyzed, highlighting the most abundant biomarkers and the main protein factors. Proteomic data corroborated previously demonstrated stone-related ecological distribution. For instance, these data showed starvation-inducible, biofilm-related and DNA-protection proteins as signatures of the microbes associated with the interior, surface and outside of stones, respectively.  相似文献   
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Here we report the full genome sequence of Modestobacter marinus strain BC501, an actinobacterial isolate that thrives on stone surfaces. The generated chromosome is circular, with a length of 5.57 Mb and a G+C content of 74.13%, containing 5,445 protein-coding genes, 48 tRNAs, and 3 ribosomal operons.  相似文献   
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Bacillus circulans was able to produce extracellular levansucrase using sucrose as carbon source optimally at 35°C. The enzymic synthesis of levan and fructo-oligosaccharides was studied using a 50% ethanol fraction of crude extract. The molecular weight of the synthesized levan was markedly affected by sucrose concentration, the molecular weight of levan decreased with increased sucrose concentration up to 32% whereby fructo-oligosaccharides were isolated. Temperature and the reaction time clearly affected the conversion of fructose to levan with molecular weight values ranging from 10 to 38 kDa. Identification of levan indicated that fructose was the building unit of the levan obtained. Thermal and pH stabilities of B. circulans levansucrase could be improved by enzyme glycosylation using sodium metaperiodate treatment. Chemical modification provides additional points of attachment of the enzyme to the support which offered the modified enzyme greater stabilization than did the free enzyme. The modified enzyme exhibited thermal tolerance up to 50°C, where it retained 88.25% of its activity, while the free enzyme only retained 64.55% of its original activity. The half-life significantly increased from 130 min for the free enzyme to 347 min for the modified enzyme at 50°C, however, it increased from 103 min for the free enzyme to 210 min for the modified enzyme at 60°C. Other properties i.e., the response to some metal ions as well as the ability to convert higher substrate levels and tolerance to an extension of the reaction periods were also improved upon modification. Obviously, the results obtained outlined the conditions leading to the formation of important high or low molecular weight or levan and fructo-oligosaccharides suitable for different industrial applications.  相似文献   
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Two compounds (3 and 10) were isolated from the aerial parts of Sida spinosa L. Their structures have been established as glyceryl-1-eicosanoate and 20-hydroxy, 24-hydroxymethylecdysone by 1D and 2D-NMR techniques. In addition 12 known compounds (1, 2, 4-9 and 11-14) have been isolated and identified.  相似文献   
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From the fruits of Kigelia pinnata DC., a new furanone derivative formulated as 3-(2'-hydroxyethyl)-5-(2"-hydroxypropyl)-dihydrofuran-2(3H)-one (1), and four new iridoids named; 7-hydroxy viteoid II (2), 7-hydroxy eucommic acid (3), 7-hydroxy-10-deoxyeucommiol (4) and 10-deoxyeucommiol (5) have been isolated together with seven known iridoids, jiofuran (6), jioglutolide (7), 1-dehydroxy-3,4-dihydroaucubigenin (8), des-p-hydroxybenzoyl kisasagenol B (9), ajugol (10), verminoside (11) and 6-trans-caffeoyl ajugol (12). The structures of the isolated compounds were characterized by different spectroscopic methods.  相似文献   
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