排序方式: 共有124条查询结果,搜索用时 15 毫秒
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Faten Mezni Arbia Labidi Mohamed Larbi Khouja Lucy Martine Olivier Berdeaux Abdelhamid Khaldi 《化学与生物多样性》2016,13(5):544-548
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 (P < 0.001) affected phytosterol levels in these oils. 相似文献
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Ha?tham Sghaier Karima Hezbri Faten Ghodhbane-Gtari Petar Pujic Arnab Sen Daniele Daffonchio Abdellatif Boudabous Louis S Tisa Hans-Peter Klenk Jean Armengaud Philippe Normand Maher Gtari 《The ISME journal》2016,10(1):21-29
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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P Normand J Gury P Pujic B Chouaia E Crotti L Brusetti D Daffonchio B Vacherie V Barbe C Médigue A Calteau F Ghodhbane-Gtari I Essoussi I Nouioui I Abbassi-Ghozzi M Gtari 《Journal of bacteriology》2012,194(17):4773-4774
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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Heba A. El-Refai Ahmed F. Abdel-Fattah Faten A. Mostafa 《World journal of microbiology & biotechnology》2009,25(5):821-827
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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Egyptian propolis: 2. Chemical composition,antiviral and antimicrobial activities of East Nile Delta propolis 总被引:1,自引:0,他引:1
Abd El Hady FK Hegazi AG 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(3-4):386-394
Three propolis samples from East Nile Delta, Egypt were collected. Propolis samples were investigated by GC/MS,103 compounds were identified, 20 being new for propolis. Dakahlia propolis was a typical poplar propolis but it contained two new caffeate esters and two new triterpenoids. Ismailia propolis was characterized by the presence of new triterpenic acid methyl esters and it did not contain any aromatic acids, esters and flavonoids. Sharkia propolis was characterized by the presence of caffeate esters only, some di- and triterpenoids. The antiviral (Infectious Bursal Disease Virus and Reo-Virus) and antimicrobial (Staphylococcus aureus; Escherichia coli and Candida albicans) activities of propolis samples were investigated. Dakahlia propolis showed the highest antiviral activity against Infectious Bursal Disease Virus (IBDV) and the highest antibacterial activity against Escherichia coli and the highest antifungal activity against Candida albicans. While Ismailia propolis had the highest antiviral activity against Reo-virus. Sharkia propolis showed the highest antibacterial activity against Staphylococcus aureus and moderate antiviral activity against infectious bursal disease virus and reovirus. 相似文献
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