Equilibrium studies of the adsorption of fructo-oligosaccharides from a pure mixture and a fermentative broth on a Dowex Monosphere calcium resin

Fructo-oligosaccharides (FOS) namely, kestose, nystose and fructofuranosylnystose, are prebiotics that can be obtained by fermentation. The resulting fermentative broth is a complex mixture consisting also of salts and other sugars that must be removed. Adsorption equilibrium studies were conducted using the static method in batch mode onto Dowex Monosphere calcium resin, at 60ºC, for FOS contained in a fermentative broth and pure mixtures. Experimental isotherms data were analyzed using linear, Langmuir/anti-Langmuir, Freundlich, Redlich & Peterson, and Toth models. Isotherm parameters were determined using linear and nonlinear correlations for the minimization of several error functions. The nonlinear correlations were found to provide the best isotherm parameters for the models. FOS contained in a fermentative broth were well fitted with anti-Langmuir isotherms, while FOS in pure mixtures were better fitted with Toth, Langmuir and Redlich & Peterson isotherms. A detailed error analysis was carried out to investigate the effect of using different error criteria for the determination of the isotherm parameters

Reproductive biology of the pampas deer (Ozotoceros bezoarticus): a review

The pampas deer (Ozotoceros bezoarticus) is a South American grazing deer which is in extreme danger of extinction. Very little is known about the biology of the pampas deer. Moreover, most information has not been published in peer-reviewed scientific journals, and is only available in local publications, theses, etc. Therefore, our aim was to update and summarize the available information regarding the reproductive biology of the pampas deer. Moreover, in most sections, we have also included new, unpublished information. Detailed descriptions are provided of the anatomy of both the female and the male reproductive tract, puberty onset, the oestrous cycle and gestational length. Birthing and the early postpartum period are described, as are maternal behaviour and early fawn development, seasonal distribution of births, seasonal changes in male reproduction and antler cycle, reproductive behaviour, semen collection, and cryopreservation. Finally, an overview is given and future directions of research are proposed

Changes in cytokinins are sufficient to alter developmental patterns of defense metabolites in Nicotiana attenuata

Plant defense metabolites are well known to be regulated developmentally. The optimal defense (OD) theory posits that a tssue's fitness values and probability of attack should determine defense metabolite allocations. Young leaves are expected to provide a larger fitness value to the plant, and therefore their defense allocations should be higher when compared with older leaves. The mechanisms that coordinate development with defense remain unknown and frequently confound tests of the OD theory predictions. Here we demonstrate that cytokinins (CKs) modulate ontogeny-dependent defenses in Nicotiana attenuata. We found that leaf CK levels highly correlate with inducible defense expressions with high levels in young and low levels in older leaves. We genetically manipulated the developmental patterns of two different CK classes by using senescence- and chemically inducible expression of CK biosynthesis genes. Genetically modifying the levels of different CKs in leaves was sufficient to alter ontogenic patterns of defense metabolites. We conclude that the developmental regulation of growth hormones that include CKs plays central roles in connecting development with defense and therefore in establishing optimal patterns of defense allocation in plants

Equilibrium studies for the adsorption of fructo-oligosaccharides on a Dowex Monosphere calcium resin

Fructo-oligosaccharides (FOS), namely kestose, nystose and fructo-furanosylnystose, are prebiotic sugars that can be obtained from sucrose by fermentation. The resulting fermentative broth is a complex mixture containing also salts and other smaller sugars that must be removed. In this study, a Dowex Monosphere calcium resin was evaluated for the separation of sugars. The adsorption behavior of FOS contained in a fermentative broth was compared with FOS from purified mixtures. Experiments were performed in static batch mode at 60ºC. Experimental isotherms data were analyzed using linear, Langmuir/anti-Langmuir, Freundlich, Redlich & Peterson, and Toth type models. Isotherm parameters were estimated using linear and non-linear correlations for the minimization of several error functions. The non-linear correlations were found to provide the best isotherm parameters for the models. FOS adsorption showed different behaviors depending on the complexity of the liquid phase of the FOS mixtures studied. The experimental adsorption data of FOS contained in purified mixtures were well fitted with the anti-Langmuir isotherm, while FOS in a fermentative broth were better fitted with Toth and Langmuir isotherms

Timing-dependent effects of salicylic acid treatment on phytohormonal changes, ROS regulation, and antioxidant defense in salinized barley (Hordeum vulgare L.)

Cross-talk between exogenous salicylic acid (SA) and endogenous phytohormone pathways affects the antioxidant defense system and its response to salt stress. The study presented here investigated the effects of SA treatment before and during salt stress on the levels of endogenous plant growth regulators in three barley cultivars with different salinity tolerances: Hordeum vulgare L. cvs. Akhisar (sensitive), Erginel (moderate), and Kalayc (tolerant). The cultivars' relative leaf water contents, growth parameters, proline contents, chlorophyll a/b ratios, and lipid peroxidation levels were measured, along with the activities of enzymes involved in detoxifying reactive oxygen species (ROS) including superoxide-dismutase, peroxidase, catalase, ascorbate-peroxidase, and glutathione-reductase. In addition, levels of several endogenous phytohormones (indole-3-acetic-acid, cytokinins, abscisic acid, jasmonic acid, and ethylene) were measured. Barley is known to be more salt tolerant than related plant species. Accordingly, none of the studied cultivars exhibited changes in membrane lipid peroxidation under salt stress. However, they responded differently to salt-stress with respect to their accumulation of phytohormones and antioxidant enzyme activity. The strongest and weakest increases in ABA and proline accumulation were observed in Kalayc and Akhisar, respectively, suggesting that salt-stress was more effectively managed in Kalayc. The effects of exogenous SA treatment depended on both the timing of the treatment and the cultivar to which it was applied. In general, however, where SA helped mitigate salt stress, it appeared to do so by increasing ROS scavenging capacity and antioxidant enzyme activity. SA treatment also induced changes in phytohormone levels, presumably as a consequence of SA-phytohormone salt-stress cross-talk.Internal Grant Agency of Palacky University [IGA_PrF_ 2019_ 020]; European Regional Development Fund-Project Plants as a tool for sustainable global development [CZ. 02.1.01/0.0/0.0/16_019/0000827]This work was supported by the Internal Grant Agency of Palacky University N. IGA_PrF_ 2019_ 020 and from European Regional Development Fund-Project Plants as a tool for sustainable global development (No. CZ. 02.1.01/0.0/0.0/16_019/0000827). We would also like to thank to Sees-editing Ltd., U.K. for English editing of the manuscript.WOS:0005635386000092-s2.0-85089529111PubMed: 3280791