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71.
International Journal of Peptide Research and Therapeutics - The present study investigates the nephroprotective and the molecular mechanisms effects of Liza aurata protein hydrolysates (LAPHs)...  相似文献   
72.
Plant Cell, Tissue and Organ Culture (PCTOC) - The present study is a part of a program designed at improving the date palm, Phoenix dactylifera L. cv. Barhee, through induced somaclonal variation....  相似文献   
73.
Relaxation of PvuII recognition sequence   总被引:4,自引:0,他引:4  
M Nasri  S Sayadi  D Thomas 《FEBS letters》1985,185(1):101-104
The substrate specificity of PvuII endonuclease is relaxed in the presence of dimethyl sulfoxide. The new recognition sequences cleaved in pBR322 DNA have been found to be CCGCTG, CATCTG, CAGATG, CAGGTG and CAGCGG.  相似文献   
74.
The purpose of this study was to evaluate the effects of increasing levels of saponins from Quillaja saponaria on fatty acid (FA) composition and cholesterol content in muscle Longissimus dorsi of lambs. A total of 24 Barbarine lambs were assigned to four dietary treatments: control diet (C) consisting of oat hay ad libitum and 400 g of concentrate (80% barley, 17.5% soybean meal and 2.5% vitamin and mineral supplement); C diet plus 30 ppm of Q. saponaria L. (QS30); C diet plus 60 ppm of Quillaja (QS60); C diet plus 90 ppm of Quillaja (QS90). Saponin supplementation reduced the concentration of C14:1 cis-9 (P = 0.001) and of its desaturation index (P = 0.002). None of the FA intermediates of ruminal biohydrogenation (BH) was affected by Quillaja saponin supplementation (P > 0.05). The concentration of C20:4n-6 was higher in the meat of animals receiving 60 ppm of Quillaja than C and QS30 groups. Supplementing 60 ppm of Quillaja reduced the ratio between α-linolenic and linoleic acids compared with the C group (P = 0.023). We did not find any significant effect of Quillaja saponins on muscle cholesterol level. Further investigations are necessary to assess the metabolic fate of saponins in the rumen and to understand whether there is an effect of saponin on Δ9-desaturase enzyme activity, ruminal BH and cholesterol metabolism in ruminants. Supplementing up to 90 ppm of Quillaja saponins did not produce detrimental effects on the overall meat FA profile.  相似文献   
75.
An alkaline calcium dependent trypsin from the viscera of Goby (Zosterisessor ophiocephalus) was purified to homogeneity with a 16-fold increase in specific activity and 20% recovery. The purified trypsin appeared as a single band on sodium dodecyl sulphate-polyacrylamide gel (SDS-PAGE) and native-PAGE. The enzyme had an estimated molecular weight of 23.2 kDa.The optimum pH was 9.0, and the enzyme was extremely stable in various pH buffers between pH 7.0 and 11.0. The optimum temperature for enzyme activity was 60 °C, and the activity and stability of trypsin was highly dependent on the presence of calcium ion. At 60 °C, Ca2+ (5 mM) stimulated the protease activity by 220%. The trypsin kinetic constants, Km and kcat, were 0.312 mM and 2.03 s?1.The enzyme showed high stability towards non-ionic surfactants and oxidizing agent. In addition, the enzyme showed excellent stability and compatibility with some commercial solid and liquid detergents.  相似文献   
76.
Alkalophilic Bacillus licheniformis NH1 strain produced at least five major extracellular proteases and a unique amylase as showed by zymography technique. The optimum pH and temperature for the proteolytic activity were 10.0 and 70 °C, respectively, while those of amylolytic activity were 6.5 and 90 °C, respectively. The alkaline proteases and thermostable α-amylase showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40 °C, and relative stability towards oxidizing agents. Additionally, the crude enzyme showed excellent stability and compatibility with various solid and liquid detergents. Wash performance analysis revealed that the NH1 crude enzyme could effectively remove a variety of stains, such as blood, chocolate and barbecue sauce. Considering its promising properties, B. licheniformis NH1 crude enzyme containing both α-amylase and proteases activities may be considered a potential candidate for future use in detergent processing industries.  相似文献   
77.
Fish flours from Sardinelle (Sardinella aurita) were prepared and tested for protease production by Bacillus subtilis. Protease synthesis was strongly induced when cells were grown in media containing only a combined head and viscera preparation. Sardinelle heads and viscera flour enhanced protease production up to 100% more than commercial peptones. The enhancement could have been due to a high lipid content, which might have contained nutritional factors acting as inducers, since defatting fish meal led to a decrease in protease production.  相似文献   
78.
Various fish protein hydrolysates (FPH) from sardinella (Sardinella aurita) were used as nitrogen sources for the production of extracellular lipase by the filamentous fungus Rhizopus oryzae. The best results were obtained with defatted meat–fish protein hydrolysates (DMFPH), indicating the presence in the lipid fraction of some constituents which may repress lipase synthesis. Furthermore, it was found that the extensive hydrolysis of fish proteins resulted in a higher lipase production. The use of 40 g DMFPH l–1 for the growth of Rhizopus oryzae in medium R1 resulted in a lipase production of 394 U ml–1, higher than the yield obtained with standard soy peptone as nitrogen source (373 U ml–1). The most appropriate medium for the growth and the production of lipase is composed only of 24 g DMFPH l–1 and 10 g glucose l–1, indicating that the strain can obtain its nitrogen and salts requirements directly from fish substrate.  相似文献   
79.
Amphipoda and Isopoda were sampled in 40 Tunisian wetlands, and their fauna were compared at four different types: lagoon, sebkhas, dams and hill reservoir. At each station, eight quadrates of 50 × 50 cm were randomly placed. Amphipoda and Isopoda were collected by hand. They were identified to species level. At each station, analyses of organic matter, sodium, calcium and heavy metals content from the soil collected in each station were performed. We recorded 19 and eight species for respectively Isopoda and Amphipoda and caught 3,035 specimens in total. The highest isopod's species richness (11 species) was noted around hill reservoirs and dams, a quite similar richness in the banks of lagoons (10 species) but only six species in the sebkhas. Eight amphipod species were recorded in the supralittoral zone of lagoons, three species around sebkhas but no amphipods were found in samples from dams and hill reservoirs. Isopod species richness was positively correlated with soil humidity. However, the distribution of the species Orchestia mediterranea, Orchestia gammarellus, Orchestia montagui, Orchestia stephenseni and Platorchestia platensis was related to soil metal concentrations.  相似文献   
80.
Under the standard reaction conditions, the restriction endonuclease HindIII cleaves double-stranded DNA, within the recognition sequence--A/AGCTT--at the position indicated by the arrow. In the presence of dimethyl sulfoxide the substrate specificity of this enzyme is reduced and cleavages occur at additional sites. We have determined the secondary sites in pBR322 DNA recognized by HindIII endonuclease under relaxed conditions and found that it cleaves the hexanucleotides: G/AGCTT, A/GGCTT, A/TGCTT, A/ATCTT, A/AGCCT, A/AGCAT, A/AGCGT, A/AGCTC, at the positions indicated by the arrows, producing fragments with cohesive ends.  相似文献   
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