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81.
Sawsan Amara Ahmed Fendri Nadia Ben Salem Youssef Gargouri Nabil Miled 《Applied biochemistry and biotechnology》2010,162(4):942-952
Higher animal's lipases are well characterized; however, much less is known about lipases from mollusks. A lipolytic activity was located in the land snail (Eobania vermiculata) digestive glands (hepatopancreas), from which a snail digestive lipase (SnDL) was purified. Pure SnDL has a molecular mass of 60 kDa; it does not present the interfacial activation phenomenon. It was found to be more active on short-chain triacylglycerols than on long-chain triacylglycerols. The NH2-terminal sequence of the SnDL shows 66% of identity with the 17 NH2-terminal amino acids of a putative lipase from sea urchin (Strongylocentrotus purpuratus). No sequence identity was found with known lipases. Interestingly, neither colipase nor bile salts were detected in the snail hepatopancreas. This suggests that colipase evolved in vertebrates simultaneously with the appearance of an exocrine pancreas and a true liver which produces bile salts. Altogether, these results suggest that SnDL is a member of a new group of digestive lipases belonging to invertebrates. 相似文献
82.
Recent developments in microbial inulinases 总被引:15,自引:0,他引:15
Ashok Pandey Carlos R. Soccol Ponniah Selvakumar Vanete T. Soccol Nadia Krieger Jose D. Fontana 《Applied biochemistry and biotechnology》1999,81(1):35-52
Microbial inulinases are an important class of industrial enzymes that have gained much attention recently. Inulinases can
be produced by a host of microorganisms, including fungi, yeast, and bacteria. Among them, however, Aspergillus sp. (filamentous fungus) and Kluyveromyces sp. (diploid yeast) are apparently the preferred choices for commercial applications. Among various substrates (carbon source)
employed for their production, inulin-containing plant materials offer advantages in comparison to pure substrates. Although
submerged fermentation has been universally used as the technique of fermentation, attempts are being made to develop solidstate
fermentation technology also. Inulinases catalyze the hydrolysis of inulin to d-fructose (fructose syrup), which has gained an important place in human diets today. In addition, inulinases are finding
other newer applications. This article reviews more recent developments, especially those made in the past decade, on microbial
inulinases—its production using various microorganisms and substrates. It also describes the characteristics of various forms
of inulinases produced as well as their applications. 相似文献
83.
84.
Michelina Soccio Nadia Lotti Lara Finelli Massimo Gazzano Andrea Munari 《Journal of Polymer Science.Polymer Physics》2010,48(17):1901-1910
Poly(glycolic acid) (PGA) and a series of novel random copolymers of PGA containing 2‐hydroxyisobutyrric acid (PGAPHIB) (HIB unit content from 1.5 to 7.4 mol %) were synthesized and characterized in terms of chemical structure and molecular weight. Afterward, the polyesters were examined by thermogravimetric analysis, differential scanning calorimetry, and X‐ray diffraction techniques. The copolymers, which displayed a better thermal stability than PGA, at room temperature appeared as semicrystalline materials: the main effect of copolymerization was a lowering in the amount of crystallinity and a decrease of the melting temperature with respect to homopolymer PGA. Baur's equation described well the Tm‐composition data. X‐ray diffraction measurements allowed the identification of the PGA crystalline structure in all cases. After melt quenching, semicrystalline samples were obtained with the exception of PGAPHIB7.4 copolymer. The introduction of HIB units decreased the crystallization rate compared with pure PGA. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1901–1910, 2010 相似文献
85.
The starane herbicide was spectrophotometrically determined by the diazotization method in a flow injection assembly. Since starane is a substituted pyridyl compound the NH2 group at the p-position was exploited for diazotization. Starane was diazotized with nitrite and the diazotized product is coupled with beta-naphthol. The absorbance of the resulting azo dye was measured at 395 nm with a molar absorptivity of 1.5 x 10(4) L mol(-1) cm(-1). The calibration graph was linear over the range of 0.6 to 10 microg/mL, with a relative standard deviation (RSD) of 1.67% and a sampling through put of 60 samples h(-1). The % recovery for the determination of starane was found to be 96%. The method was successfully applied to the determination of the active ingredient of starane herbicide in its formulation as well as in food samples. 相似文献
86.
87.
We provide a simple proof of the Moreau-Rockafellar theorem that a proper lower semicontinuous convex function on a Banach space is determined up to a constant by its subdifferential.
88.
Franck Charmantray Nadia Touisni Laurence Hecquet Thierry Noguer Christine Mousty 《Electroanalysis》2015,27(6):1341-1344
This paper describes the development of an amperometric biosensor based on galactose oxidase (GAOx) immobilization within a laponite clay film deposited on Carbon Screen‐Printed Electrodes modified by electrodeposited Prussian Blue and coated with poly‐(O‐phenylenediamine) (PPD/PB/CSPEs). Amperometric performances of GAOx@laponite/PPD/PB/CSPEs bioelectrodes were determined using several GAOx substrates. Using these modified electrodes the reduction of enzymatically generated hydrogen peroxide was performed at ?0.2 V vs. Ag‐AgCl. In an initial attempt, E.Coli transketolase activity on its immobilized form was followed using a bienzymatic GAOx‐TK biosensor. 相似文献
89.
Nadia Morcos Manar Omran Hala Ghanem Mahmoud Elahdal Nashwa Kamel Elbatoul Attia 《Photochemistry and photobiology》2015,91(4):942-951
One inescapable feature of life on the earth is exposure to ionizing radiation. The thyroid gland is one of the most sensitive organs to gamma‐radiation and endocrine disrupters. Low‐level laser therapy (LLLT) has been used to stimulate tissue repair, and reduce inflammation. The aim of this study was to gauge the value of using Helium–Neon laser to repair the damaged tissues of thyroid gland after gamma‐irradiation. Albino rats were used in this study (144 rats), divided into control, gamma, laser, and gamma plus laser‐irradiated groups, each group was divided into six subgroups according to time of treatment (total six sessions). Rats were irradiated once with gamma radiation (6 Gy), and an external dose of laser (Wavelength 632.8 nm, 12 mW, CW, Illuminated area 5.73 cm2, 2.1 mW cm?2, 120 s, 1.4 J, 0.252 J cm?2) twice weekly localized on thyroid region of the neck, for a total of six sessions. Animals were sacrificed after each session. Analysis included thyroid function, oxidative stress markers, liver function and blood picture. Results revealed improvement in thyroid function, liver function and antioxidant levels, and the blood cells count after LLLT. 相似文献
90.
Genetic diversity and haplotype structure of 21 Y‐STRs,including nine noncore loci,in South Tunisian Population: Forensic relevance 下载免费PDF全文
Faten Makki‐Rmida Arwa Kammoun Nadia Mahfoudh Adnene Ayadi Abdullah Ahmed Gibriel Bakhta Mallek Leila Maalej Zouheir Hammami Samir Maatoug Hafedh Makni Saber Masmoudi 《Electrophoresis》2015,36(23):2908-2913
Y chromosome STRs (Y‐STRs) are being used frequently in forensic laboratories. Previous studies of Y‐STR polymorphisms in different groups of the Tunisian population identified low levels of diversity and discrimination capacity (DC) using various commercial marker sets. This definitely limits the use of such systems for Y‐STRs genotyping in Tunisia. In our investigation on South Tunisia, 200 unrelated males were typed for the 12 conventional Y‐STRs included in the PowerPlex® Y System. Additional set of nine noncore Y‐STRs including DYS446, DYS456, DYS458, DYS388, DYS444, DYS445, DYS449, DYS710, and DYS464 markers were genotyped and evaluated for their potential in improving DC. Allele frequency, gene diversity, haplotype diversity (HD), and DC calculation revealed that DYS464 was the most diverse marker followed by DYS710 and DYS449 markers. The standard panel of 12 Y‐STRs (DC = 80.5%) and the nine markers were combined to obtain DC of 99%. Among the 198 different haplotypes observed, 196 haplotypes were unique (HD = 99.999). Out of the nine noncore set, six Y‐STRs (DYS458, DYS456, DYS449, DYS710, DYS444, and DYS464) had the greatest impact on enhancing DC. Our data provided putative Y‐STRs combination to be used for genetic and forensic applications. 相似文献