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931.
Raci Ekinci Ayca Küçükçuban Sebahattin Nas 《Preparative biochemistry & biotechnology》2016,46(3):247-253
The aim of this study was to evaluate the use of mono and mixed lactic acid bacteria (LAB) cultures to determine suitable LAB combinations for a type II sourdough system. In this context, previously isolated sourdough LAB strains with antimicrobial activity, which included Lactobacillus plantarum PFC22, Lactobacillus brevis PFC31, Pediococcus acidilactici PFC38, and Lactobacillus sanfranciscensis PFC80, were used as mono or mixed culture combinations in a fermentation system to produce type II sourdough, and subsequently in bread dough production. Compared to the monoculture fermentation of dough, the use of mixed cultures shortened the adaptation period by half. In addition, the use of mixed cultures ensured higher microbial viability, and enhanced the fruity flavor during bread dough production. It was determined that the combination of L. plantarum PFC22 + P. acidilactici PFC38 + L. sanfranciscensis PFC80 is a promising culture mixture that can be used in the production of type II sourdough systems, and that may also contribute to an increase in metabolic activity during bread production process. 相似文献
932.
By means of cobra venom factor (CVF) it is demonstrated that the stimulation of hexosemonophosphate shunt (HMPS) of human polymorphonuclear leukocytes (PMN) by zymosan (Z) and dextran sulfate (DS) is caused by at least two models of activation: (a) via activation caused by phagocytosis, (b) via activated alternative pathway of complement activation (APC). Active factors of APC presented with phagocytizable objects strongly enhance activation of PMN. The effect of APC can be observed in serum-containing as well as in serum-free cultures. It can be demonstrated that in serum-free cultures the factors of APC participating in the activation of PMN are supplied by monocytes. By use of synthetic hexapeptide (HP) representing the COOH-terminal sequence of human C3 further evidence is provided that factors of APC are able to activate the PMN. 相似文献
933.
Anna U?arowska Giuseppe Dionisio Barbara Sarholz Hans-Peter Piepho Mingliang Xu Christina R?nn Ingvardsen Gerhard Wenzel Thomas Lübberstedt 《BMC plant biology》2009,9(1):15
Background
The potyviruses sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are major pathogens of maize worldwide. Two loci, Scmv1 and Scmv2, have ealier been shown to confer complete resistance to SCMV. Custom-made microarrays containing previously identified SCMV resistance candidate genes and resistance gene analogs were utilised to investigate and validate gene expression and expression patterns of isogenic lines under pathogen infection in order to obtain information about the molecular mechanisms involved in maize-potyvirus interactions. 相似文献934.
935.
Bio‐economy and human being A widely accepted vision is a prerequisite for an effective prevention and successful overcoming of inevitable acceptance problems during the implementation process of a bio‐economy strategy. The best biotech / bio‐economic innovation can not be implemented in a welfare enhancing way, if the following conditions are not met: 1) innovation‐related, normative issues have to be already discussed at the societal level before or during the development of innovations, 2) the associated risks and opportunities are identified and communicated and 3) strategies to avoid these risks are developed. All this requires participation of the affected societal groups along with effective communication strategies. 相似文献
936.
Novel, thick-film biosensors have been developed for the determination of l-glutamate in foodstuffs. The sensors were prepared by immobilization of l-glutamate oxidase by using polycarbamylsulfonate-hydrogel on a thick-film sensor. l-Glutamate oxidases obtained from Streptomyces sp. with different degree of purification were compared with their characteristic response to l-glutamate at different conditions and for their specificity, inhibition, and storage properties. These sensors were applied to determine monosodium glutamate in soy sauce samples and show good correlation with colorimetric method. 相似文献
937.
Sucrose, glucose, fructose, and melibiose in different concentrations and combinations in the induction media influenced the viability of the isolated maize microspores and the formation of multinuclear structures. The induction of multinuclear structures on media containing combination of sucrose, fructose and glucose was lower than on media only with sucrose. In media containing melibiose alone or in combination with sucrose, no induction of multinuclear structures was found, however, microspore viability was improved. 相似文献
938.
Equivalent genetic roles for bmp7/snailhouse and bmp2b/swirl in dorsoventral pattern formation 总被引:6,自引:0,他引:6
Schmid B Fürthauer M Connors SA Trout J Thisse B Thisse C Mullins MC 《Development (Cambridge, England)》2000,127(5):957-967
A bone morphogenetic protein (BMP) signaling pathway acts in the establishment of the dorsoventral axis of the vertebrate embryo. Here we demonstrate the genetic requirement for two different Bmp ligand subclass genes for dorsoventral pattern formation of the zebrafish embryo. From the relative efficiencies observed in Bmp ligand rescue experiments, conserved chromosomal synteny, and isolation of the zebrafish bmp7 gene, we determined that the strongly dorsalized snailhouse mutant phenotype is caused by a mutation in the bmp7 gene. We show that the original snailhouse allele is a hypomorphic mutation and we identify a snailhouse/bmp7 null mutant. We demonstrate that the snailhouse/bmp7 null mutant phenotype is identical to the presumptive null mutant phenotype of the strongest dorsalized zebrafish mutant swirl/bmp2b, revealing equivalent genetic roles for these two Bmp ligands. Double mutant snailhouse/bmp7; swirl/bmp2b embryos do not exhibit additional or stronger dorsalized phenotypes, indicating that these Bmp ligands do not function redundantly in early embryonic development. Furthermore, overexpression experiments reveal that Bmp2b and Bmp7 synergize in the ventralization of wild-type embryos through a cell-autonomous mechanism, suggesting that Bmp2b/Bmp7 heterodimers may act in vivo to specify ventral cell fates in the zebrafish embryo. 相似文献
939.
940.
An increasing number of broadly neutralizing monoclonal antibodies (bnMAb) against the HIV-1 envelope (Env) protein has been discovered recently. Despite this progress, vaccination efforts with the aim to re-elicit bnMAbs that provide protective immunity have failed so far. Herein, we describe the development of a mammalian cell based FACS-panning method in which bnMAbs are used as tools to select surface-exposed envelope variants according to their binding affinity. For that purpose, an HIV-1 derived lentiviral vector was developed to infect HEK293T cells at low multiplicity of infection (MOI) in order to link Env phenotype and genotype. For proof of principle, a gp145 Env model-library was established in which the complete V3 domain was substituted by five strain specific V3 loop sequences with known binding affinities to nMAb 447-52D, respectively. Env genes were recovered from selected cells by PCR, subcloned into a lentiviral vector (i) to determine and quantify the enrichment nMAb binders and (ii) to generate a new batch of transduction competent particles. After 2 selection cycles the Env variant with highest affinity was enriched 20-fold and represented 80% of the remaining Env population. Exploiting the recently described bnMAbs, this procedure might prove useful in selecting Env proteins from large Env libraries with the potential to elicit bnMAbs when used as vaccine candidates. 相似文献