Concentrated Sucrose Solutions Research Articles

Successive Fermentation of Aguamiel and Molasses by Aspergillus oryzae and Saccharomyces cerevisiae to Obtain High Purity Fructooligosaccharides

Fructooligosaccharides (FOS) are usually synthesized with pure enzymes using highly concentrated sucrose solutions. In this work, low-cost aguamiel and molasses were explored as sucrose alternatives to produce FOS, via whole-cell fermentation, with an Aspergillus oryzae DIA-MF strain. FOS production process was optimized through a central composite experimental design, with two independent variables: initial sucrose concentration in a medium composed of aguamiel and molasses (AgMe), and inoculum concentration. The optimized process—165 g/L initial sucrose in AgMe (adjusted with concentrated molasses) and 1 × 107 spores/mL inoculum concentration—resulted in an FOS production of 119 ± 12 g/L and a yield of 0.64 ± 0.05 g FOS/g GFi. Among the FOSs produced were kestose, nystose, 1-fructofuranosyl-nystose, and potentially a novel trisaccharide produced by this strain. To reduce the content of mono- and disaccharides in the mixture, run a successive fermentation was run with two Saccharomyces cerevisiae strains. Fermentations run with S. cerevisiae S227 improved FOS purity in the mixture from 39 ± 3% to 61.0 ± 0.6% (w/w) after 16 h of fermentation. This study showed that agro-industrial wastes such as molasses with aguamiel are excellent alternatives as substrate sources for the production of prebiotic FOS, resulting in a lower-cost process.

Flowering plants serve nutritional needs of Ascogaster quadridentata (Hymenoptera: Braconidae), a key parasitoid of codling moth

The codling moth Cydia pomonella (Linnaeus, 1758) (Lepidoptera: Tortricidae) is the major pome fruit pest worldwide, causing direct fruit damage and significant yield losses. The egg-larval koinobiont parasitoid Ascogaster quadridentata (Wesmael, 1835) (Hymenoptera: Braconidae) contributes to the natural regulation of codling moth populations. Similar to many other parasitoid Hymenoptera, adult A. quadridentata could also benefit from high plant diversity in orchards if it fed on flowers. However, its particular nutritional requirements are rather unknown. For the first time, possible effects of sugar or flower resources on the performance of this parasitoid were studied in laboratory experiments. Wasps fed with highly concentrated sucrose or glucose solutions lived three to five times longer than starving individuals. Trehalose also supported survival, whereas mannose was not suitable. Parasitoids were able to exploit sugar solutions of low (10%) to high (64%) concentrations. Survival was more than twice as long when flowers of buckwheat, coriander, wild carrot, and parsnip were offered. Parasitism capacity was strongly linked to female longevity and thus to adequate nutrition of adults. Under the prevailing experimental conditions, performance of wasps was three times higher on flower diet compared to that of starved wasps. Suitable plants flowering during the activity period of A. quadridentata might therefore improve the ecosystem service provided by this important codling moth parasitoid and help increasing functional biodiversity in orchards.

Novel Evolutionary Engineering Approach to Alter Substrate Specificity of Disaccharide Transporter Mal11 in Saccharomyces cerevisiae

A major challenge in the research of transport proteins is to understand how single amino acid residues contribute to their structure and biological function. Amino acid substitutions that result in a selective advantage in adaptive laboratory evolution experiments can provide valuable hints at their role in transport proteins. In this study, we applied an evolutionary engineering strategy to alter the substrate specificity of the proton-coupled disaccharide transporter Mal11 in Saccharomyces cerevisiae, which has affinity for sucrose, maltose and glucose. The introduction of MAL11 in a strain devoid of all other sugar transporters and disaccharide hydrolases restored growth on glucose but rendered the strain highly sensitive to the presence of sucrose or maltose. Evolution in glucose-limited continuous cultures with pulse-wise addition of a concentrated sucrose solution at increasing frequency resulted in the enrichment of spontaneous mutant cells that were less sensitive to the presence of sucrose and maltose. Sequence analysis showed that in each of the two independent experiments, three mutations occurred in MAL11, which were found responsible for the disaccharide-insensitive phenotype via reverse engineering. Our work demonstrates how laboratory evolution with proton-motive force-driven uptake of a non-metabolizable substrate can be a powerful tool to provide novel insights into the role of specific amino acid residues in the transport function of Mal11.

Relationship Between Toxicity of Cryoprotectants, Osmotic and Oxidative Stresses In Awassi Ram Sperm

BACKGROUND:The relationship between the toxicity of cryoprotectants and their osmotic and/or oxidative stresses remains to be further investigated .OBJECTIVE:To investigate the toxic effects of different cryoprotectants and osmotic stress on Awassi ram sperm and to determine the relationship between oxidative and antioxidative status of the sperm.MATERIALS AND METHODS:Pooled sperm samples were exposed to sucrose solutions of different concentrations (75 to 900 mOsm) and isosmotic condition (290-325 mOsm) was re-established by adding HEPES buffered Tyrode's lactate. Sperm samples were mixed with 0.5, 1.0 and 1.5 M of glycerol, methanol, 2-methoxyethanol, dimethylacetamide or 1,2propanediol for 5 min and returned to isosmotic condition. Sperm samples were exposed to cryoprotectants at 4°C for 2 hours and isosmotic conditions were re-established. Motility, viability, acrosome integrity and oxidative or antioxidative parameters were determined.RESULTS:Treatment with hypo- or hyperosmotic sucrose solution reduced motility and viability without affecting acrosome integrity. The addition and removal of glycerol and dimethylacetamide (1.0 or 1.5 M) decreased sperm motility, while cryoprotectants had no effect on viability except for 1.5 M glycerol. Chilling significantly reduced the motility and viability of the sperm, but not the acrosome integrity. Rapid addition or removal of cryoprotectants also did not affect the acrosome integrity. Cryoprotectants changed only the ceruloplasmin level, while there were significant post-chilling differences in lipid hydroperoxide, paraoxonase and ceruloplasmin levels.CONCLUSION:Cryoprotectants without other additives have limited protection and glycerol can be toxic to spermatozoa. The oxidative stress plays a role in cryoprotectant toxicity and chilling stress.

Storage Stability of Chilled and Frozen Starch Gels as Affected by Blended Starch Formulation, Sucrose Syrup, and Coconut Milk.

Effects of starch formulation, highly concentrated sucrose solution, and coconut milk on the stability of starch gels kept under chilled and frozen conditions were determined. Gels containing rice starch (RS), tapioca starch (TS) (RS:TS of 1 : 0.85), and hydroxypropyl distarch phosphate (HDP, 0-50% of total starch) were prepared from 15% starch suspension using water, 45°Brix sucrose syrup or coconut milk as liquid media. After aging at 4°C for 21 days, starch gels had higher hardness and chewiness, with lower cohesiveness and springiness (p ≤ 0.05). Water-based gels containing HDP had less extent of texture hardening, lower degree of crystallinity, and more homogeneous microstructure during 4°C aging. However, for the starch gels in sucrose syrup or coconut milk, HDP induced greater gel hardening, higher degree of crystallinity, and denser gel microstructure during chilled storage. This could be due to the crystallization of sucrose or lipid/amylose-lipid complexes. Nevertheless, HDP enhanced freeze-thaw stability of the gels, regardless of the liquid media used (p ≤ 0.05). According to the consumer test of the model desserts subjected to a single freeze-thaw cycle, the sample containing 50% HDP gel in sucrose syrup or 25% HDP gel in coconut milk gained the highest hedonic score of texture and overall acceptance (p ≤ 0.05).

Dissecting the contribution of 5-HT1A auto- and heteroreceptors in sucrose overconsumption in mice

The rise in obesity prevalence has been linked to overconsumption of high-sugar containing food and beverages. Recent evidence suggests that chronic sucrose consumption leads to changes in serotonergic neuroplasticity within the neural circuits involved in feeding control. Although there is a relationship between serotonin signalling in the brain and diet-induced obesity, the specific serotonin (5-HT) receptors or pathways involved remain unknown. The 5-HT1A receptor subtype plays a role in regulating mood, anxiety, and appetite, and has been associated with reversing addiction to substances of abuse. However, the respective role of 5-HT1A auto- vs heteroreceptors in sucrose consumption has not been examined. Mice were given controlled access to either 5%, 10% or 25% w/v sucrose, or water as a control, for 12 weeks using the well-established “drinking in the dark” protocol (n = 6–8 mice per group). Ligands selectively targeting 5-HT1A auto- and/or heteroreceptors (NLX-112, unbiased 5-HT1A receptor agonist; NLX-101, preferential heteroreceptor agonist; F13714, preferential autoreceptor agonist) were administered i.p. acutely after 6 and 12 weeks of sucrose consumption. The specific involvement of 5-HT1A receptors in these effects was verified by blockade with the selective 5-HT1A receptors antagonist WAY-100,635. The specific subpopulation of 5-HT1A receptors involved in sucrose consumption was dependent on the concentration of sucrose solution and the duration of exposure to sucrose (6 weeks vs 12 weeks). Long-term sucrose consumption leads to accentuated 5-HT1A autoreceptor function. Thus, targeting 5-HT1A autoreceptors might represent an effective therapeutic strategy to combat the rise in obesity resulting from the overconsumption of high-sugar diet.

Higher toxin tolerance to triptolide, a terpenoid foraged by a sympatric honeybee

The thunder god vine, Tripterygium hypoglaucum, is a toxic nectar plant distributed across China. A terpenoid, called triptolide (TRP), found in nectar can impair honeybees’ foraging responses, dance communication, and olfactory learning. In the present study, we tested the tolerances of the native honeybee Apis cerana and the introduced honeybee A. mellifera to short-term and long-term exposure to TRP. The results showed that introduced A. mellifera is more vulnerable in fatality to high concentrations of TRP sucrose solution (5 and 10 µg TRP mL−1) than A. cerana. We also compared the short-term and long-term exposure effects of TRP on olfactory learning and memory between the two honeybee species, and the olfactory learning and memory of both honey bee species showed impaired performance after both 2 h or 7 days of being fed with TRP sucrose solution. However, A. cerana showed a higher tolerance and resistance to TRP toxin than A. mellifera. Our results support a coevolution hypothesis in that the native species A. cerana has higher toxin tolerance than the introduced species A. mellifera.

Evaluation of the importance of ionic and osmotic components of salt stress on the photosynthetic efficiency of epiphytic lichens

Salt stress can significantly disrupt the functioning of lichens which are self-sufficient symbiotic organisms inhabiting various severe environments. The aim was to test the effect of salt and sucrose on the photosynthetic efficiency of two selected epiphytic lichens inhabiting the interior of the land. Firstly, we compared the effect of salt and sucrose solutions of different concentrations. Secondly, the effect of salt and sucrose solutions with identical osmotic pressures was compared. The results showed that short-term salt stress leads to a significant reduction of FV/FM, greater changes in chlorophyll fluorescence parameters and OJIP transients compared to the osmotic effects induced by sucrose. This proved that the negative impact of salt stress is associated primarily with ionic effects. The most symptomatic effect of the ionic stress was a significant reduction of the utilisation of trapped energy in electron transport and thereby down-regulation of electron transfer. Since lichens are resistant to a temporary lack of water, ionic stress could have more serious consequences than osmotic stress itself. Hypogymnia physodes was more sensitive to salt stress than Pseudevernia furfuracea, but the reduction of photosynthetic efficiency was not permanent since after 24 h FV/FM returned to the level characteristic for healthy lichens. Nevertheless, repeated exposure to salt may reduce the vitality of lichens growing along communication routes sprinkled with salt in the winter season. Finally, the changes in certain JIP-test parameters were stronger than FV/FM, thus they could be better indicators of salt stress in lichens.

Determination of Optical Rotation Based on Liquid Crystal Polymer Vortex Retarder and Digital Image Processing

A polarimeter for optical rotation (OR) detection and optical active media measurement based on m=1 Zero-Order Liquid Crystal Polymer Vortex Half-Wave Retarder (LCPVR) and Digital Image Processing (DIP) was proposed in this letter. In this research, we demonstrate the principle of measuring optical rotation with LCPVR polarimeter system which is based on Jones vectors and matrices. Two opposing wedge-shaped dark areas will appear in the output image when the uniform distribution polarized light passes the LCPVR. DIP is used to find the darkest line in the opposing wedge-shaped dark areas, then the optical rotation angle is calculated, which is from −90 degree to +90 degree. The polarimeter is used to measure the concentration of sucrose solutions at the range of 1000-10000mg/dl L. We also present the fabricated method of LCPVR by Digital Micro-mirror Device (DMD) system, and the LCPVR will be low price in the fabricated processing. Compared with existed polarimeter, our polarimeter with LCPVR has simpler optical structure and less size. The key innovation of this system is that the optical rotation angle can be displayed with visualized image except digital. And the rotation angle is calculated by DIP without mechanical adjust a 1/4 wave plate, which lead to higher detection speed and stronger stability.

Sucrose solution concentration and the intermittent access induced consumption increase

Animals fed ad libitum consume less of a preferred additional food with daily access than with access only once every few days. With 4% sucrose solution, rats can drink over twice as much in a day if they receive it every fourth day compared to daily access. These differences are maintained when all rats are put on the same schedule. We explored the intermittency effect with 1, 4, 8, and 16% sucrose solutions available for 23 h daily or every third day in adult male rats. The consumption difference was only evident with the 4% solution. In a second experiment with a 16% solution, only a small difference was seen in the first phase. When the sucrose concentration was lowered to 4% in a second phase with alternate day access, the rats with prior every third-day access showed an immediate, pronounced elevation in consumption compared to rats with initial daily access. These results suggest that intermittency induces a long-lasting elevation in the sucrose solution's value for rats, but it may only be evident under the appropriate testing conditions. The relevance of this increased consumption for understanding human obesity and binge eating is discussed.

Comparative study of microwave assisted and conventional osmotic dehydration of apple cubes at a constant temperature

To study the effects of microwave power (MWP) and different solution concentration (sucrose) on mass transfer kinetics and quality parameters of apple cubes (15 mm) at temperature (45 ± 1 °C) during microwave assisted osmotic dehydration (MWOD), and comparison with conventional osmotic dehydration (COD) and non-linear regression analysis to validate the best model based on R 2 and RMSE. MWOD was carried out in different concentrations of sucrose solution (40, 50, 60° Brix) with MWP (10, 20, 30% of maximum power (700W)) at temperature (45 ± 1 °C). Finally, the finish drying of the osmosed samples is carried out in tray drier (8 h at 70 ± 0.2 °C). MWOD is a better process in increasing the moisture loss (ML), color change (ΔE), chroma while combating solids gain (SG) and hue angle as compared to COD. Henderson and Pabis model showed the best fit of the three. Because of the least SG, MWOD can be used for the formation of dried products used in various dishes like apple cake, apple pie, etc with lower sugar content that may be beneficial for the sugar patients. Microwaves should be preferably used at low MWP (<30%) and can be used for the preservation of fruits such as Pears. • Microwave assisted osmotic dehydration, beneficial for diabetic patients is a better process compared to conventional one. • Increase in color change (ΔE) and decrease in hue angle observed. • High microwave power at constant temperature retains the quality attributes of apple cubes. • Henderson and Pabis model showed the best fit out of the three models used.

Enhanced solar-driven evaporation process via f-MWCNTs/PVDF photothermal membrane for forward osmosis draw solution recovery

Product water recovery and draw solution (DS) reuse is the most energy-intensive stage in forward osmosis (FO) technology. Sucrose solution is the most suitable DS for FO application in food and beverages. However, sucrose DS recovery by conventional pressure-driven or thermal-driven concentration techniques consumes high energy. Herein, we developed a spontaneous and sustainable solar-driven evaporation process based on a photothermal membrane for the concentration and recovery of sucrose solution. The photothermal membrane composed of multi-walled carbon nanotubes (f-MWCNTs) phtotothermal layer on a hydrophilic polyvinylidene fluoride (PVDF) substrate. The f-MWCNTs photothermal layer with rough surface and interconnected network structures not only improves the light harvesting and light-to-heat conversion performance, but also facilitates the transport of water molecules. The hydrophilic PVDF substrate can promote the rapid transport of water for adequate water supply to photothermal layer. As a result, the optimized f-MWCNTs/PVDF photothermal membrane exhibits an excellent light absorption of 95%, and a high surface temperature of 74 °C at 1 kW m−2. Besides, it realizes an evaporation rate of 1.17 kg m−2 h−1 for 5% (w/v) of sucrose solution, which is about 5 times higher than that of the natural evaporation. The designed photothermal evaporation process is capable of concentrating sucrose solution efficiently from 5% to 75% (w/v), which has great potential in FO process and juice concentration.

Thermally insulating robust carbon composite foams with high EMI shielding from natural cotton

• Conversion of biomass, medical-grade cotton and sucrose, into carbon foams by filter-pressing. • Foams exhibit density in the range of 0.06 to 0.31 g cm −3 . • Foams possess reasonable compressive strength in the range 5 kPa to 1.4 MPa. • Foams possess partial compressibility. • Low thermal conductivity (0.069 to 0.185 W m − 1 K −1 ) and good flame resistance. • carbon composite foams are amenable to machining using conventional machines and tools. • CCFs materials showed good electrical and EMI shielding properties. • The rigid CCFs showed shielding effectiveness in the ranges of 21.5 to 38.9 dB with adsorption dominant shielding properties. Thermally insulating and fire-resistant carbon composite foams are prepared by consolidating natural cotton fibre dispersed in aqueous sucrose solution by filter-pressing followed by drying and carbonization. The compressive strength (5 kPa to 1.4 MPa) and thermal conductivity (0.069 to 0.185 W m − 1 K − 1 ) depend on the foam density (0.06 to 0.31 g cm −3 ) which is modulated by varying the sucrose solutions concentration (100 to 700 g L − 1 ). Partially flexible to the rigid transition of the carbon composite foams occurs at sucrose concentration above 200 g L − 1 . The tubular carbon fibre formed from cotton is welded at their contact points by the amorphous carbon produced from sucrose leading to partial flexibility at low sucrose concentration and advancement of fibre- to- fibre bonding area at higher sucrose concentration results in rigid foam. The porosity in the inter-fibre space and lumen of the carbonized cotton fibre contributes to the low thermal conductivity. The carbon composite foams prepared at a sucrose solution concentration of 500 g L − 1 and above are amenable to machining using conventional machines and tools. The rigid carbon foams show EMI shielding effectiveness and specific shielding effectiveness in the ranges of 21.5 to 38.9 dB and 108–138 dB cm 3 g − 1 , respectively.

Reduced caloric intake allows access-induced consumption differences to emerge with concentrated sucrose solutions

Rats given intermittent access to 4% (w/v) sucrose solution elevate their consumption of solution relative to rats with continuous access, a difference that does not appear at higher concentrations. Here, we examined the hypothesis that a limit on the intake of sucrose calories prevents rats from demonstrating access-induced differences in consumption of a more concentrated sucrose solution. Energy-replete rats were given every day (ED) or every third day (E3D) access to sucrose solutions adulterated with bitter quinine which reduced solution palatability and consumption levels while intake was measured. In experiment 1, previously collected data were compiled to examine the trajectory of consumption of continuously available 4% sucrose solution which was shown to stabilize by day 3 and then informed group assignment. In experiment 2, daily consumption levels were higher for rats with E3D access to 4% sucrose solution than rats with ED access to the same solution, whereas rats consumed similar amounts of 8% sucrose solution across access schedules. In the first hour of solution availability rats with E3D access showed elevated sucrose solution consumption, relative to rats with ED access, for both 4% and 8% sucrose solution. Upon the addition of quinine (0.005%) sucrose solution consumption decreased and the E3D access group consumed more daily sucrose solution than the ED access group for both 4% and 8% sucrose solution. In experiment 3, four groups of rats were given ED or E3D access to 8% sucrose solution adulterated with 0.0025%, 0.005%, 0.01%, or 0.02% quinine. Quinine adulteration reduced 8% sucrose solution consumption and allowed rats with E3D access to elevate their consumption levels relative to rats with ED access; this effect persisted when all groups were switched to 8% sucrose + 0.02% quinine solution. Thus, daily access-induced consumption differences develop but do not emerge because of a caloric limit on sucrose solution intake. This work underscores the interaction of availability and caloric intake as determinants of sugar consumption and highlights an important distinction between animal models of food addiction and binge eating.

Approximation of dynamic membrane distillation processes applied to concentration of aqueous sucrose solutions

In this work, a method is presented for the approximation of dynamic processes. Dynamic inputs of membrane distillation can be approximated by a regression equation as several steady state steps after each other. A regression equation of the flux was developed based on a validated steady state model and a wide range of process parameters. The regression equation of the flux is then used to approximate a dynamic process. To test the approximation on a dynamic process, a new test setup was developed to provide quick changes to the temperatures or flow. It was found that the approximation corresponds well to the test results. While this paper only approximates the flux, the method presented in this paper can also be used to approximate other variables. The presented method is also applied to the concentration of aqueous sucrose solutions with an AGMD module with oleophobic and hydrophobic properties. Three semi batch tests were done. The approximation corresponds well to the test results. A maximum Brix concentration of 56.9 was reached in the tests.

Detection of Escherichia coli K12 in Water Using Slot Waveguide in Cascaded Ring Resonator

Escherichia coli (E. coli) bacteria can cause serious fatal health problems in human, thus early and quick pathogen detection of these bacteria is a crucial issue in hospitals, food industry, and pharmaceutical companies. Detection of E. coli K12 in drinking water source can be considered of water pollution with sewage that is vitally important in public health service. In this work, a plasmonic slot waveguide from Si3N4-SiO2 is designed and applied in an asymmetric double stage ring resonator (DSRR) for the label free detection of E. coli K12 in drinking water. The performance of DSRR sensor is studied for different concentrations of Nacl and sucrose solutions and a contaminated water sample with E.coli K12 using variational finite-difference time domain (var-FDTD) method. The sensitivity of the DSRR sensor for detection of E. coli K12 in the visible wavelengths is measured to be 461–480 nm/RIU, which leads to the minimum limit of detection (LOD) of 3.33× 10−5. In comparison with the conventional devices and methods for detection of E. coli bacterium, our proposed sensor benefits of microscale size, high resolution sensing, and short time of detection.

Research on the characteristics of Klein–Cook parameter and diffraction efficiency of acousto-optic interaction for low-frequency ultrasonic in the liquid

We have investigated the characteristics of acousto-optic interaction for low-frequency ultrasonic wave in a liquid. Based on the coupling wave equation of acousto-optic interaction, the diffraction light characteristics for normal incidence at small parameter Q have been discussed. The parameter Q with respect to acousto-optic interaction length, ultrasonic frequency, water temperature, and the concentration of sucrose solution have been analyzed, which is an important physical quantity and reflects the degree of mismatch in the acousto-optic interaction. The diffraction efficiencies for different parameters Q, incident angles and phase shifts have been calculated. The results of our work provide theoretical basis for further study of the acousto-optic effect in the liquid.

Hydrolysis and transglycosylation activities of glycosidases from small intestine brush-border membrane vesicles

In order to know the catalytic activities of the disaccharidases expressed in the mammalian small intestinal brush-border membrane vesicles (BBMV) high concentrated solutions of sucrose, maltose, isomaltulose, trehalose and the mixture sucrose:lactose were incubated with pig small intestine disaccharidases. The hydrolysis and transglycosylation reactions generated new di- and trisaccharides, characterized and quantified by GC–MS and NMR, except for trehalose where only hydrolysis was detected. In general, α-glucosyl-glucoses and α-glucosyl-fructoses were the most abundant structures, whereas no fructosyl-fructoses or fructosyl-glucoses were found. The in-depth structural characterization of the obtained carbohydrates represents a new alternative to understand the potential catalytic activities of pig small intestinal disaccharidases. The hypothesis that the oligosaccharides synthesized by glycoside hydrolases could be also hydrolysed by the same enzymes was confirmed. This information could be extremely useful in the design of new non-digestible or partially digestible oligosaccharides with potential prebiotic properties.

Влияние температуры и влажности воздуха на жизнеспособность пыльцы рапса озимого

The environments have a direct impact on formation and functioning of the generative organs in plants. Parameters characterizing viability of pollen grains are closely linked with weather conditions, especially temperature and air moisture. Very often a phase of a beginning of flowering of winter rapeseed (end of March – beginning of April) lasts in unfavourable conditions. In April 2020, we studied influence of the main weather factors (frosts, low moisture) on germination of pollen grains of the varieties Loris, Sarmat and hybrids 40059 × Jesper 16– 132 and 40008 × INRA of winter rapeseed bred in VNIIMK. Pollen viability was determined by B.A. Trankovsky’s method, accounting amount of germinating pollen grains on the artificial nutrient medium, calculating a percentage of germinating pollen grains to their total quantity. We determined optimal concentration of sucrose solution (20%) in a nutrient medium for germination of pollen of winter rapeseed varieties and hybrids. Due to our results, lowered air temperatures (from -0.5 to -1.9 оС) combined with air moisture from 39 to 86% in a period of beginning of crop flowering negatively influenced on germination of pollen grains. Viability of pollen of the varieties Loris and Sarmat was in average 47 and 37%, respectively. Pollen grains of the hybrids (F1 40059 × 52 Jesper 16-132 and F1 40008 × INRA) had less viability – 38 and 21%, respectively, this certifies higher susceptibility of tissues of the reproductive organs to low temperature and moisture.

Differential Effects of Maternal High Fat Diet During Pregnancy and Lactation on Taste Preferences in Rats.

Maternal intake of high fat diet (HFD) increases risk for obesity and metabolic disorders in offspring. Developmental programming of taste preference is a potential mechanism by which this occurs. Whether maternal HFD during pregnancy, lactation, or both, imposes greater risks for altered taste preferences in adult offspring remains a question, and in turn, was investigated in the present study. Four groups of offspring were generated based on maternal HFD access: (1) HFD during pregnancy and lactation (HFD); (2) HFD during pregnancy (HFD-pregnancy); (3) HFD during lactation (HFD-lactation); and (4) normal diet (ND) during pregnancy and lactation (ND). Adult offspring 70 days of age underwent sensory and motivational taste preference testing with various concentrations of sucrose and Intralipid solutions using brief-access automated gustometers (Davis-rigs) and 24 h two-bottle choice tests, respectively. To control for post-gestational diet effects, offspring in all experimental groups were weaned on ND, and did not differ in body weight or glucose tolerance at the time of testing. Offspring exposed to maternal HFD showed increased sensory taste responses for 0.3, 0.6, 1.2 M sucrose solutions in HFD and 0.6 M in HFD-pregnancy groups, compared to animals exposed to ND. Similar effects were noted for lower concentrations of Intralipid in HFD (0.05, 0.10%) and HFD-pregnancy (0.05, 0.10, 0.5%) groups. The HFD-lactation group showed an opposite, diminished responsiveness for sucrose at the highest concentrations (0.9, 1.2, 1.5 M), but not for Intralipid, compared to ND animals. Extended-access two-bottle tests did not reveal major difference across the groups. Our study shows that maternal HFD during pregnancy and lactation has markedly different effects on preferences for palatable sweet and fatty solutions in adult offspring and suggests that such developmental programing may primarily affect gustatory mechanisms. Future studies are warranted for determining the impact of taste changes on development of obesity and metabolic disorders in a “real” food environment with food choices available, as well as to identify specific underlying mechanisms.